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420a0d19 CE |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
2ea97746 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
420a0d19 CE |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* Functions for handling an incoming SMTP call. */ | |
9 | ||
10 | ||
11 | #include "exim.h" | |
2ea97746 | 12 | #include <assert.h> |
420a0d19 CE |
13 | |
14 | ||
15 | /* Initialize for TCP wrappers if so configured. It appears that the macro | |
16 | HAVE_IPV6 is used in some versions of the tcpd.h header, so we unset it before | |
17 | including that header, and restore its value afterwards. */ | |
18 | ||
19 | #ifdef USE_TCP_WRAPPERS | |
20 | ||
21 | #if HAVE_IPV6 | |
22 | #define EXIM_HAVE_IPV6 | |
23 | #endif | |
24 | #undef HAVE_IPV6 | |
25 | #include <tcpd.h> | |
26 | #undef HAVE_IPV6 | |
27 | #ifdef EXIM_HAVE_IPV6 | |
28 | #define HAVE_IPV6 TRUE | |
29 | #endif | |
30 | ||
31 | int allow_severity = LOG_INFO; | |
32 | int deny_severity = LOG_NOTICE; | |
33 | uschar *tcp_wrappers_name; | |
34 | #endif | |
35 | ||
36 | ||
37 | /* Size of buffer for reading SMTP commands. We used to use 512, as defined | |
38 | by RFC 821. However, RFC 1869 specifies that this must be increased for SMTP | |
39 | commands that accept arguments, and this in particular applies to AUTH, where | |
2ea97746 | 40 | the data can be quite long. More recently this value was 2048 in Exim; |
420a0d19 | 41 | however, RFC 4954 (circa 2007) recommends 12288 bytes to handle AUTH. Clients |
2ea97746 CE |
42 | such as Thunderbird will send an AUTH with an initial-response for GSSAPI. |
43 | The maximum size of a Kerberos ticket under Windows 2003 is 12000 bytes, and | |
420a0d19 CE |
44 | we need room to handle large base64-encoded AUTHs for GSSAPI. |
45 | */ | |
46 | ||
2ea97746 | 47 | #define SMTP_CMD_BUFFER_SIZE 16384 |
420a0d19 CE |
48 | |
49 | /* Size of buffer for reading SMTP incoming packets */ | |
50 | ||
2ea97746 | 51 | #define IN_BUFFER_SIZE 8192 |
420a0d19 CE |
52 | |
53 | /* Structure for SMTP command list */ | |
54 | ||
55 | typedef struct { | |
56 | const char *name; | |
57 | int len; | |
58 | short int cmd; | |
59 | short int has_arg; | |
60 | short int is_mail_cmd; | |
61 | } smtp_cmd_list; | |
62 | ||
63 | /* Codes for identifying commands. We order them so that those that come first | |
64 | are those for which synchronization is always required. Checking this can help | |
65 | block some spam. */ | |
66 | ||
67 | enum { | |
68 | /* These commands are required to be synchronized, i.e. to be the last in a | |
69 | block of commands when pipelining. */ | |
70 | ||
71 | HELO_CMD, EHLO_CMD, DATA_CMD, /* These are listed in the pipelining */ | |
72 | VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */ | |
73 | ETRN_CMD, /* This by analogy with TURN from the RFC */ | |
74 | STARTTLS_CMD, /* Required by the STARTTLS RFC */ | |
2ea97746 | 75 | TLS_AUTH_CMD, /* auto-command at start of SSL */ |
420a0d19 CE |
76 | |
77 | /* This is a dummy to identify the non-sync commands when pipelining */ | |
78 | ||
79 | NON_SYNC_CMD_PIPELINING, | |
80 | ||
81 | /* These commands need not be synchronized when pipelining */ | |
82 | ||
83 | MAIL_CMD, RCPT_CMD, RSET_CMD, | |
84 | ||
85 | /* This is a dummy to identify the non-sync commands when not pipelining */ | |
86 | ||
87 | NON_SYNC_CMD_NON_PIPELINING, | |
88 | ||
2ea97746 CE |
89 | /* RFC3030 section 2: "After all MAIL and RCPT responses are collected and |
90 | processed the message is sent using a series of BDAT commands" | |
91 | implies that BDAT should be synchronized. However, we see Google, at least, | |
92 | sending MAIL,RCPT,BDAT-LAST in a single packet, clearly not waiting for | |
93 | processing of the RCPT response(s). We shall do the same, and not require | |
94 | synch for BDAT. Worse, as the chunk may (very likely will) follow the | |
95 | command-header in the same packet we cannot do the usual "is there any | |
96 | follow-on data after the command line" even for non-pipeline mode. | |
97 | So we'll need an explicit check after reading the expected chunk amount | |
98 | when non-pipe, before sending the ACK. */ | |
99 | ||
100 | BDAT_CMD, | |
101 | ||
420a0d19 CE |
102 | /* I have been unable to find a statement about the use of pipelining |
103 | with AUTH, so to be on the safe side it is here, though I kind of feel | |
104 | it should be up there with the synchronized commands. */ | |
105 | ||
106 | AUTH_CMD, | |
107 | ||
108 | /* I'm not sure about these, but I don't think they matter. */ | |
109 | ||
110 | QUIT_CMD, HELP_CMD, | |
111 | ||
2ea97746 | 112 | #ifdef SUPPORT_PROXY |
420a0d19 CE |
113 | PROXY_FAIL_IGNORE_CMD, |
114 | #endif | |
115 | ||
116 | /* These are specials that don't correspond to actual commands */ | |
117 | ||
118 | EOF_CMD, OTHER_CMD, BADARG_CMD, BADCHAR_CMD, BADSYN_CMD, | |
119 | TOO_MANY_NONMAIL_CMD }; | |
120 | ||
121 | ||
122 | /* This is a convenience macro for adding the identity of an SMTP command | |
123 | to the circular buffer that holds a list of the last n received. */ | |
124 | ||
125 | #define HAD(n) \ | |
126 | smtp_connection_had[smtp_ch_index++] = n; \ | |
127 | if (smtp_ch_index >= SMTP_HBUFF_SIZE) smtp_ch_index = 0 | |
128 | ||
129 | ||
130 | /************************************************* | |
131 | * Local static variables * | |
132 | *************************************************/ | |
133 | ||
2ea97746 CE |
134 | static struct { |
135 | BOOL auth_advertised :1; | |
420a0d19 | 136 | #ifdef SUPPORT_TLS |
2ea97746 CE |
137 | BOOL tls_advertised :1; |
138 | # ifdef EXPERIMENTAL_REQUIRETLS | |
139 | BOOL requiretls_advertised :1; | |
140 | # endif | |
141 | #endif | |
142 | BOOL dsn_advertised :1; | |
143 | BOOL esmtp :1; | |
144 | BOOL helo_required :1; | |
145 | BOOL helo_verify :1; | |
146 | BOOL helo_seen :1; | |
147 | BOOL helo_accept_junk :1; | |
148 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
149 | BOOL pipe_connect_acceptable :1; | |
420a0d19 | 150 | #endif |
2ea97746 CE |
151 | BOOL rcpt_smtp_response_same :1; |
152 | BOOL rcpt_in_progress :1; | |
153 | BOOL smtp_exit_function_called :1; | |
154 | #ifdef SUPPORT_I18N | |
155 | BOOL smtputf8_advertised :1; | |
420a0d19 | 156 | #endif |
2ea97746 CE |
157 | } fl = { |
158 | .helo_required = FALSE, | |
159 | .helo_verify = FALSE, | |
160 | .smtp_exit_function_called = FALSE, | |
161 | }; | |
162 | ||
163 | static auth_instance *authenticated_by; | |
164 | static int count_nonmail; | |
420a0d19 | 165 | static int nonmail_command_count; |
420a0d19 CE |
166 | static int synprot_error_count; |
167 | static int unknown_command_count; | |
168 | static int sync_cmd_limit; | |
169 | static int smtp_write_error = 0; | |
170 | ||
171 | static uschar *rcpt_smtp_response; | |
172 | static uschar *smtp_data_buffer; | |
173 | static uschar *smtp_cmd_data; | |
174 | ||
175 | /* We need to know the position of RSET, HELO, EHLO, AUTH, and STARTTLS. Their | |
176 | final fields of all except AUTH are forced TRUE at the start of a new message | |
177 | setup, to allow one of each between messages that is not counted as a nonmail | |
178 | command. (In fact, only one of HELO/EHLO is not counted.) Also, we have to | |
179 | allow a new EHLO after starting up TLS. | |
180 | ||
181 | AUTH is "falsely" labelled as a mail command initially, so that it doesn't get | |
182 | counted. However, the flag is changed when AUTH is received, so that multiple | |
183 | failing AUTHs will eventually hit the limit. After a successful AUTH, another | |
184 | AUTH is already forbidden. After a TLS session is started, AUTH's flag is again | |
185 | forced TRUE, to allow for the re-authentication that can happen at that point. | |
186 | ||
187 | QUIT is also "falsely" labelled as a mail command so that it doesn't up the | |
2ea97746 CE |
188 | count of non-mail commands and possibly provoke an error. |
189 | ||
190 | tls_auth is a pseudo-command, never expected in input. It is activated | |
191 | on TLS startup and looks for a tls authenticator. */ | |
420a0d19 CE |
192 | |
193 | static smtp_cmd_list cmd_list[] = { | |
2ea97746 CE |
194 | /* name len cmd has_arg is_mail_cmd */ |
195 | ||
420a0d19 CE |
196 | { "rset", sizeof("rset")-1, RSET_CMD, FALSE, FALSE }, /* First */ |
197 | { "helo", sizeof("helo")-1, HELO_CMD, TRUE, FALSE }, | |
198 | { "ehlo", sizeof("ehlo")-1, EHLO_CMD, TRUE, FALSE }, | |
199 | { "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE }, | |
2ea97746 | 200 | #ifdef SUPPORT_TLS |
420a0d19 | 201 | { "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE }, |
2ea97746 CE |
202 | { "tls_auth", 0, TLS_AUTH_CMD, FALSE, FALSE }, |
203 | #endif | |
420a0d19 CE |
204 | |
205 | /* If you change anything above here, also fix the definitions below. */ | |
206 | ||
207 | { "mail from:", sizeof("mail from:")-1, MAIL_CMD, TRUE, TRUE }, | |
208 | { "rcpt to:", sizeof("rcpt to:")-1, RCPT_CMD, TRUE, TRUE }, | |
209 | { "data", sizeof("data")-1, DATA_CMD, FALSE, TRUE }, | |
2ea97746 | 210 | { "bdat", sizeof("bdat")-1, BDAT_CMD, TRUE, TRUE }, |
420a0d19 CE |
211 | { "quit", sizeof("quit")-1, QUIT_CMD, FALSE, TRUE }, |
212 | { "noop", sizeof("noop")-1, NOOP_CMD, TRUE, FALSE }, | |
213 | { "etrn", sizeof("etrn")-1, ETRN_CMD, TRUE, FALSE }, | |
214 | { "vrfy", sizeof("vrfy")-1, VRFY_CMD, TRUE, FALSE }, | |
215 | { "expn", sizeof("expn")-1, EXPN_CMD, TRUE, FALSE }, | |
216 | { "help", sizeof("help")-1, HELP_CMD, TRUE, FALSE } | |
217 | }; | |
218 | ||
219 | static smtp_cmd_list *cmd_list_end = | |
220 | cmd_list + sizeof(cmd_list)/sizeof(smtp_cmd_list); | |
221 | ||
222 | #define CMD_LIST_RSET 0 | |
223 | #define CMD_LIST_HELO 1 | |
224 | #define CMD_LIST_EHLO 2 | |
225 | #define CMD_LIST_AUTH 3 | |
226 | #define CMD_LIST_STARTTLS 4 | |
2ea97746 | 227 | #define CMD_LIST_TLS_AUTH 5 |
420a0d19 CE |
228 | |
229 | /* This list of names is used for performing the smtp_no_mail logging action. | |
230 | It must be kept in step with the SCH_xxx enumerations. */ | |
231 | ||
232 | static uschar *smtp_names[] = | |
233 | { | |
2ea97746 CE |
234 | US"NONE", US"AUTH", US"DATA", US"BDAT", US"EHLO", US"ETRN", US"EXPN", |
235 | US"HELO", US"HELP", US"MAIL", US"NOOP", US"QUIT", US"RCPT", US"RSET", | |
236 | US"STARTTLS", US"VRFY" }; | |
420a0d19 | 237 | |
2ea97746 | 238 | static uschar *protocols_local[] = { |
420a0d19 CE |
239 | US"local-smtp", /* HELO */ |
240 | US"local-smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
241 | US"local-esmtp", /* EHLO */ | |
242 | US"local-esmtps", /* EHLO->STARTTLS->EHLO */ | |
243 | US"local-esmtpa", /* EHLO->AUTH */ | |
244 | US"local-esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
245 | }; | |
2ea97746 CE |
246 | static uschar *protocols[] = { |
247 | US"smtp", /* HELO */ | |
248 | US"smtps", /* The rare case EHLO->STARTTLS->HELO */ | |
249 | US"esmtp", /* EHLO */ | |
250 | US"esmtps", /* EHLO->STARTTLS->EHLO */ | |
251 | US"esmtpa", /* EHLO->AUTH */ | |
252 | US"esmtpsa" /* EHLO->STARTTLS->EHLO->AUTH */ | |
253 | }; | |
420a0d19 CE |
254 | |
255 | #define pnormal 0 | |
256 | #define pextend 2 | |
257 | #define pcrpted 1 /* added to pextend or pnormal */ | |
258 | #define pauthed 2 /* added to pextend */ | |
420a0d19 CE |
259 | |
260 | /* Sanity check and validate optional args to MAIL FROM: envelope */ | |
261 | enum { | |
2ea97746 | 262 | ENV_MAIL_OPT_NULL, |
420a0d19 CE |
263 | ENV_MAIL_OPT_SIZE, ENV_MAIL_OPT_BODY, ENV_MAIL_OPT_AUTH, |
264 | #ifndef DISABLE_PRDR | |
265 | ENV_MAIL_OPT_PRDR, | |
266 | #endif | |
420a0d19 | 267 | ENV_MAIL_OPT_RET, ENV_MAIL_OPT_ENVID, |
2ea97746 CE |
268 | #ifdef SUPPORT_I18N |
269 | ENV_MAIL_OPT_UTF8, | |
270 | #endif | |
271 | #ifdef EXPERIMENTAL_REQUIRETLS | |
272 | ENV_MAIL_OPT_REQTLS, | |
420a0d19 | 273 | #endif |
420a0d19 CE |
274 | }; |
275 | typedef struct { | |
276 | uschar * name; /* option requested during MAIL cmd */ | |
277 | int value; /* enum type */ | |
278 | BOOL need_value; /* TRUE requires value (name=value pair format) | |
279 | FALSE is a singleton */ | |
280 | } env_mail_type_t; | |
281 | static env_mail_type_t env_mail_type_list[] = { | |
282 | { US"SIZE", ENV_MAIL_OPT_SIZE, TRUE }, | |
283 | { US"BODY", ENV_MAIL_OPT_BODY, TRUE }, | |
284 | { US"AUTH", ENV_MAIL_OPT_AUTH, TRUE }, | |
285 | #ifndef DISABLE_PRDR | |
286 | { US"PRDR", ENV_MAIL_OPT_PRDR, FALSE }, | |
287 | #endif | |
420a0d19 CE |
288 | { US"RET", ENV_MAIL_OPT_RET, TRUE }, |
289 | { US"ENVID", ENV_MAIL_OPT_ENVID, TRUE }, | |
2ea97746 CE |
290 | #ifdef SUPPORT_I18N |
291 | { US"SMTPUTF8",ENV_MAIL_OPT_UTF8, FALSE }, /* rfc6531 */ | |
420a0d19 | 292 | #endif |
2ea97746 CE |
293 | #ifdef EXPERIMENTAL_REQUIRETLS |
294 | /* https://tools.ietf.org/html/draft-ietf-uta-smtp-require-tls-03 */ | |
295 | { US"REQUIRETLS",ENV_MAIL_OPT_REQTLS, FALSE }, | |
296 | #endif | |
297 | /* keep this the last entry */ | |
298 | { US"NULL", ENV_MAIL_OPT_NULL, FALSE }, | |
420a0d19 CE |
299 | }; |
300 | ||
301 | /* When reading SMTP from a remote host, we have to use our own versions of the | |
302 | C input-reading functions, in order to be able to flush the SMTP output only | |
303 | when about to read more data from the socket. This is the only way to get | |
304 | optimal performance when the client is using pipelining. Flushing for every | |
305 | command causes a separate packet and reply packet each time; saving all the | |
306 | responses up (when pipelining) combines them into one packet and one response. | |
307 | ||
308 | For simplicity, these functions are used for *all* SMTP input, not only when | |
309 | receiving over a socket. However, after setting up a secure socket (SSL), input | |
310 | is read via the OpenSSL library, and another set of functions is used instead | |
311 | (see tls.c). | |
312 | ||
313 | These functions are set in the receive_getc etc. variables and called with the | |
314 | same interface as the C functions. However, since there can only ever be | |
315 | one incoming SMTP call, we just use a single buffer and flags. There is no need | |
316 | to implement a complicated private FILE-like structure.*/ | |
317 | ||
318 | static uschar *smtp_inbuffer; | |
319 | static uschar *smtp_inptr; | |
320 | static uschar *smtp_inend; | |
321 | static int smtp_had_eof; | |
322 | static int smtp_had_error; | |
323 | ||
324 | ||
2ea97746 CE |
325 | /* forward declarations */ |
326 | static int smtp_read_command(BOOL check_sync, unsigned buffer_lim); | |
327 | static int synprot_error(int type, int code, uschar *data, uschar *errmess); | |
328 | static void smtp_quit_handler(uschar **, uschar **); | |
329 | static void smtp_rset_handler(void); | |
330 | ||
331 | /************************************************* | |
332 | * Recheck synchronization * | |
333 | *************************************************/ | |
334 | ||
335 | /* Synchronization checks can never be perfect because a packet may be on its | |
336 | way but not arrived when the check is done. Normally, the checks happen when | |
337 | commands are read: Exim ensures that there is no more input in the input buffer. | |
338 | In normal cases, the response to the command will be fast, and there is no | |
339 | further check. | |
340 | ||
341 | However, for some commands an ACL is run, and that can include delays. In those | |
342 | cases, it is useful to do another check on the input just before sending the | |
343 | response. This also applies at the start of a connection. This function does | |
344 | that check by means of the select() function, as long as the facility is not | |
345 | disabled or inappropriate. A failure of select() is ignored. | |
346 | ||
347 | When there is unwanted input, we read it so that it appears in the log of the | |
348 | error. | |
349 | ||
350 | Arguments: none | |
351 | Returns: TRUE if all is well; FALSE if there is input pending | |
352 | */ | |
353 | ||
354 | static BOOL | |
355 | wouldblock_reading(void) | |
356 | { | |
357 | int fd, rc; | |
358 | fd_set fds; | |
359 | struct timeval tzero; | |
360 | ||
361 | #ifdef SUPPORT_TLS | |
362 | if (tls_in.active.sock >= 0) | |
363 | return !tls_could_read(); | |
364 | #endif | |
365 | ||
366 | if (smtp_inptr < smtp_inend) | |
367 | return FALSE; | |
368 | ||
369 | fd = fileno(smtp_in); | |
370 | FD_ZERO(&fds); | |
371 | FD_SET(fd, &fds); | |
372 | tzero.tv_sec = 0; | |
373 | tzero.tv_usec = 0; | |
374 | rc = select(fd + 1, (SELECT_ARG2_TYPE *)&fds, NULL, NULL, &tzero); | |
375 | ||
376 | if (rc <= 0) return TRUE; /* Not ready to read */ | |
377 | rc = smtp_getc(GETC_BUFFER_UNLIMITED); | |
378 | if (rc < 0) return TRUE; /* End of file or error */ | |
379 | ||
380 | smtp_ungetc(rc); | |
381 | return FALSE; | |
382 | } | |
383 | ||
384 | static BOOL | |
385 | check_sync(void) | |
386 | { | |
387 | if (!smtp_enforce_sync || !sender_host_address || f.sender_host_notsocket) | |
388 | return TRUE; | |
389 | ||
390 | return wouldblock_reading(); | |
391 | } | |
392 | ||
393 | ||
394 | /* If there's input waiting (and we're doing pipelineing) then we can pipeline | |
395 | a reponse with the one following. */ | |
396 | ||
397 | static BOOL | |
398 | pipeline_response(void) | |
399 | { | |
400 | if ( !smtp_enforce_sync || !sender_host_address | |
401 | || f.sender_host_notsocket || !f.smtp_in_pipelining_advertised) | |
402 | return FALSE; | |
403 | ||
404 | if (wouldblock_reading()) return FALSE; | |
405 | f.smtp_in_pipelining_used = TRUE; | |
406 | return TRUE; | |
407 | } | |
408 | ||
409 | ||
410 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
411 | static BOOL | |
412 | pipeline_connect_sends(void) | |
413 | { | |
414 | if (!sender_host_address || f.sender_host_notsocket || !fl.pipe_connect_acceptable) | |
415 | return FALSE; | |
416 | ||
417 | if (wouldblock_reading()) return FALSE; | |
418 | f.smtp_in_early_pipe_used = TRUE; | |
419 | return TRUE; | |
420 | } | |
421 | #endif | |
422 | ||
423 | /************************************************* | |
424 | * Log incomplete transactions * | |
425 | *************************************************/ | |
426 | ||
427 | /* This function is called after a transaction has been aborted by RSET, QUIT, | |
428 | connection drops or other errors. It logs the envelope information received | |
429 | so far in order to preserve address verification attempts. | |
430 | ||
431 | Argument: string to indicate what aborted the transaction | |
432 | Returns: nothing | |
433 | */ | |
434 | ||
435 | static void | |
436 | incomplete_transaction_log(uschar *what) | |
437 | { | |
438 | if (sender_address == NULL || /* No transaction in progress */ | |
439 | !LOGGING(smtp_incomplete_transaction)) | |
440 | return; | |
441 | ||
442 | /* Build list of recipients for logging */ | |
443 | ||
444 | if (recipients_count > 0) | |
445 | { | |
446 | int i; | |
447 | raw_recipients = store_get(recipients_count * sizeof(uschar *)); | |
448 | for (i = 0; i < recipients_count; i++) | |
449 | raw_recipients[i] = recipients_list[i].address; | |
450 | raw_recipients_count = recipients_count; | |
451 | } | |
452 | ||
453 | log_write(L_smtp_incomplete_transaction, LOG_MAIN|LOG_SENDER|LOG_RECIPIENTS, | |
454 | "%s incomplete transaction (%s)", host_and_ident(TRUE), what); | |
455 | } | |
456 | ||
457 | ||
458 | ||
459 | ||
460 | void | |
461 | smtp_command_timeout_exit(void) | |
462 | { | |
463 | log_write(L_lost_incoming_connection, | |
464 | LOG_MAIN, "SMTP command timeout on%s connection from %s", | |
465 | tls_in.active.sock >= 0 ? " TLS" : "", host_and_ident(FALSE)); | |
466 | if (smtp_batched_input) | |
467 | moan_smtp_batch(NULL, "421 SMTP command timeout"); /* Does not return */ | |
468 | smtp_notquit_exit(US"command-timeout", US"421", | |
469 | US"%s: SMTP command timeout - closing connection", | |
470 | smtp_active_hostname); | |
471 | exim_exit(EXIT_FAILURE, US"receiving"); | |
472 | } | |
473 | ||
474 | void | |
475 | smtp_command_sigterm_exit(void) | |
476 | { | |
477 | log_write(0, LOG_MAIN, "%s closed after SIGTERM", smtp_get_connection_info()); | |
478 | if (smtp_batched_input) | |
479 | moan_smtp_batch(NULL, "421 SIGTERM received"); /* Does not return */ | |
480 | smtp_notquit_exit(US"signal-exit", US"421", | |
481 | US"%s: Service not available - closing connection", smtp_active_hostname); | |
482 | exim_exit(EXIT_FAILURE, US"receiving"); | |
483 | } | |
484 | ||
485 | void | |
486 | smtp_data_timeout_exit(void) | |
487 | { | |
488 | log_write(L_lost_incoming_connection, | |
489 | LOG_MAIN, "SMTP data timeout (message abandoned) on connection from %s F=<%s>", | |
490 | sender_fullhost ? sender_fullhost : US"local process", sender_address); | |
491 | receive_bomb_out(US"data-timeout", US"SMTP incoming data timeout"); | |
492 | /* Does not return */ | |
493 | } | |
494 | ||
495 | void | |
496 | smtp_data_sigint_exit(void) | |
497 | { | |
498 | log_write(0, LOG_MAIN, "%s closed after %s", | |
499 | smtp_get_connection_info(), had_data_sigint == SIGTERM ? "SIGTERM":"SIGINT"); | |
500 | receive_bomb_out(US"signal-exit", | |
501 | US"Service not available - SIGTERM or SIGINT received"); | |
502 | /* Does not return */ | |
503 | } | |
504 | ||
505 | ||
506 | ||
507 | /* Refill the buffer, and notify DKIM verification code. | |
508 | Return false for error or EOF. | |
509 | */ | |
510 | ||
511 | static BOOL | |
512 | smtp_refill(unsigned lim) | |
513 | { | |
514 | int rc, save_errno; | |
515 | if (!smtp_out) return FALSE; | |
516 | fflush(smtp_out); | |
517 | if (smtp_receive_timeout > 0) ALARM(smtp_receive_timeout); | |
518 | ||
519 | /* Limit amount read, so non-message data is not fed to DKIM. | |
520 | Take care to not touch the safety NUL at the end of the buffer. */ | |
521 | ||
522 | rc = read(fileno(smtp_in), smtp_inbuffer, MIN(IN_BUFFER_SIZE-1, lim)); | |
523 | save_errno = errno; | |
524 | if (smtp_receive_timeout > 0) ALARM_CLR(0); | |
525 | if (rc <= 0) | |
526 | { | |
527 | /* Must put the error text in fixed store, because this might be during | |
528 | header reading, where it releases unused store above the header. */ | |
529 | if (rc < 0) | |
530 | { | |
531 | if (had_command_timeout) /* set by signal handler */ | |
532 | smtp_command_timeout_exit(); /* does not return */ | |
533 | if (had_command_sigterm) | |
534 | smtp_command_sigterm_exit(); | |
535 | if (had_data_timeout) | |
536 | smtp_data_timeout_exit(); | |
537 | if (had_data_sigint) | |
538 | smtp_data_sigint_exit(); | |
539 | ||
540 | smtp_had_error = save_errno; | |
541 | smtp_read_error = string_copy_malloc( | |
542 | string_sprintf(" (error: %s)", strerror(save_errno))); | |
543 | } | |
544 | else | |
545 | smtp_had_eof = 1; | |
546 | return FALSE; | |
547 | } | |
548 | #ifndef DISABLE_DKIM | |
549 | dkim_exim_verify_feed(smtp_inbuffer, rc); | |
550 | #endif | |
551 | smtp_inend = smtp_inbuffer + rc; | |
552 | smtp_inptr = smtp_inbuffer; | |
553 | return TRUE; | |
554 | } | |
555 | ||
420a0d19 CE |
556 | /************************************************* |
557 | * SMTP version of getc() * | |
558 | *************************************************/ | |
559 | ||
560 | /* This gets the next byte from the SMTP input buffer. If the buffer is empty, | |
561 | it flushes the output, and refills the buffer, with a timeout. The signal | |
562 | handler is set appropriately by the calling function. This function is not used | |
2ea97746 | 563 | after a connection has negotiated itself into an TLS/SSL state. |
420a0d19 | 564 | |
2ea97746 | 565 | Arguments: lim Maximum amount to read/buffer |
420a0d19 CE |
566 | Returns: the next character or EOF |
567 | */ | |
568 | ||
569 | int | |
2ea97746 CE |
570 | smtp_getc(unsigned lim) |
571 | { | |
572 | if (smtp_inptr >= smtp_inend) | |
573 | if (!smtp_refill(lim)) | |
574 | return EOF; | |
575 | return *smtp_inptr++; | |
576 | } | |
577 | ||
578 | uschar * | |
579 | smtp_getbuf(unsigned * len) | |
420a0d19 | 580 | { |
2ea97746 CE |
581 | unsigned size; |
582 | uschar * buf; | |
583 | ||
420a0d19 | 584 | if (smtp_inptr >= smtp_inend) |
2ea97746 CE |
585 | if (!smtp_refill(*len)) |
586 | { *len = 0; return NULL; } | |
587 | ||
588 | if ((size = smtp_inend - smtp_inptr) > *len) size = *len; | |
589 | buf = smtp_inptr; | |
590 | smtp_inptr += size; | |
591 | *len = size; | |
592 | return buf; | |
593 | } | |
594 | ||
595 | void | |
596 | smtp_get_cache(void) | |
597 | { | |
598 | #ifndef DISABLE_DKIM | |
599 | int n = smtp_inend - smtp_inptr; | |
600 | if (n > 0) | |
601 | dkim_exim_verify_feed(smtp_inptr, n); | |
602 | #endif | |
603 | } | |
604 | ||
605 | ||
606 | /* Get a byte from the smtp input, in CHUNKING mode. Handle ack of the | |
607 | previous BDAT chunk and getting new ones when we run out. Uses the | |
608 | underlying smtp_getc or tls_getc both for that and for getting the | |
609 | (buffered) data byte. EOD signals (an expected) no further data. | |
610 | ERR signals a protocol error, and EOF a closed input stream. | |
611 | ||
612 | Called from read_bdat_smtp() in receive.c for the message body, but also | |
613 | by the headers read loop in receive_msg(); manipulates chunking_state | |
614 | to handle the BDAT command/response. | |
615 | Placed here due to the correlation with the above smtp_getc(), which it wraps, | |
616 | and also by the need to do smtp command/response handling. | |
617 | ||
618 | Arguments: lim (ignored) | |
619 | Returns: the next character or ERR, EOD or EOF | |
620 | */ | |
621 | ||
622 | int | |
623 | bdat_getc(unsigned lim) | |
624 | { | |
625 | uschar * user_msg = NULL; | |
626 | uschar * log_msg; | |
627 | ||
628 | for(;;) | |
420a0d19 | 629 | { |
2ea97746 CE |
630 | #ifndef DISABLE_DKIM |
631 | unsigned dkim_save; | |
632 | #endif | |
633 | ||
634 | if (chunking_data_left > 0) | |
635 | return lwr_receive_getc(chunking_data_left--); | |
636 | ||
637 | receive_getc = lwr_receive_getc; | |
638 | receive_getbuf = lwr_receive_getbuf; | |
639 | receive_ungetc = lwr_receive_ungetc; | |
640 | #ifndef DISABLE_DKIM | |
641 | dkim_save = dkim_collect_input; | |
642 | dkim_collect_input = 0; | |
643 | #endif | |
644 | ||
645 | /* Unless PIPELINING was offered, there should be no next command | |
646 | until after we ack that chunk */ | |
647 | ||
648 | if (!f.smtp_in_pipelining_advertised && !check_sync()) | |
420a0d19 | 649 | { |
2ea97746 CE |
650 | unsigned n = smtp_inend - smtp_inptr; |
651 | if (n > 32) n = 32; | |
652 | ||
653 | incomplete_transaction_log(US"sync failure"); | |
654 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error " | |
655 | "(next input sent too soon: pipelining was not advertised): " | |
656 | "rejected \"%s\" %s next input=\"%s\"%s", | |
657 | smtp_cmd_buffer, host_and_ident(TRUE), | |
658 | string_printing(string_copyn(smtp_inptr, n)), | |
659 | smtp_inend - smtp_inptr > n ? "..." : ""); | |
660 | (void) synprot_error(L_smtp_protocol_error, 554, NULL, | |
661 | US"SMTP synchronization error"); | |
662 | goto repeat_until_rset; | |
663 | } | |
664 | ||
665 | /* If not the last, ack the received chunk. The last response is delayed | |
666 | until after the data ACL decides on it */ | |
667 | ||
668 | if (chunking_state == CHUNKING_LAST) | |
669 | { | |
670 | #ifndef DISABLE_DKIM | |
671 | dkim_exim_verify_feed(NULL, 0); /* notify EOD */ | |
672 | #endif | |
673 | return EOD; | |
420a0d19 | 674 | } |
2ea97746 CE |
675 | |
676 | smtp_printf("250 %u byte chunk received\r\n", FALSE, chunking_datasize); | |
677 | chunking_state = CHUNKING_OFFERED; | |
678 | DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state); | |
679 | ||
680 | /* Expect another BDAT cmd from input. RFC 3030 says nothing about | |
681 | QUIT, RSET or NOOP but handling them seems obvious */ | |
682 | ||
683 | next_cmd: | |
684 | switch(smtp_read_command(TRUE, 1)) | |
685 | { | |
686 | default: | |
687 | (void) synprot_error(L_smtp_protocol_error, 503, NULL, | |
688 | US"only BDAT permissible after non-LAST BDAT"); | |
689 | ||
690 | repeat_until_rset: | |
691 | switch(smtp_read_command(TRUE, 1)) | |
692 | { | |
693 | case QUIT_CMD: smtp_quit_handler(&user_msg, &log_msg); /*FALLTHROUGH */ | |
694 | case EOF_CMD: return EOF; | |
695 | case RSET_CMD: smtp_rset_handler(); return ERR; | |
696 | default: if (synprot_error(L_smtp_protocol_error, 503, NULL, | |
697 | US"only RSET accepted now") > 0) | |
698 | return EOF; | |
699 | goto repeat_until_rset; | |
700 | } | |
701 | ||
702 | case QUIT_CMD: | |
703 | smtp_quit_handler(&user_msg, &log_msg); | |
704 | /*FALLTHROUGH*/ | |
705 | case EOF_CMD: | |
706 | return EOF; | |
707 | ||
708 | case RSET_CMD: | |
709 | smtp_rset_handler(); | |
710 | return ERR; | |
711 | ||
712 | case NOOP_CMD: | |
713 | HAD(SCH_NOOP); | |
714 | smtp_printf("250 OK\r\n", FALSE); | |
715 | goto next_cmd; | |
716 | ||
717 | case BDAT_CMD: | |
718 | { | |
719 | int n; | |
720 | ||
721 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) | |
722 | { | |
723 | (void) synprot_error(L_smtp_protocol_error, 501, NULL, | |
724 | US"missing size for BDAT command"); | |
725 | return ERR; | |
726 | } | |
727 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
728 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
729 | chunking_data_left = chunking_datasize; | |
730 | DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n", | |
731 | (int)chunking_state, chunking_data_left); | |
732 | ||
733 | if (chunking_datasize == 0) | |
734 | if (chunking_state == CHUNKING_LAST) | |
735 | return EOD; | |
736 | else | |
737 | { | |
738 | (void) synprot_error(L_smtp_protocol_error, 504, NULL, | |
739 | US"zero size for BDAT command"); | |
740 | goto repeat_until_rset; | |
741 | } | |
742 | ||
743 | receive_getc = bdat_getc; | |
744 | receive_getbuf = bdat_getbuf; /* r~getbuf is never actually used */ | |
745 | receive_ungetc = bdat_ungetc; | |
420a0d19 | 746 | #ifndef DISABLE_DKIM |
2ea97746 | 747 | dkim_collect_input = dkim_save; |
420a0d19 | 748 | #endif |
2ea97746 CE |
749 | break; /* to top of main loop */ |
750 | } | |
751 | } | |
752 | } | |
753 | } | |
754 | ||
755 | uschar * | |
756 | bdat_getbuf(unsigned * len) | |
757 | { | |
758 | uschar * buf; | |
759 | ||
760 | if (chunking_data_left <= 0) | |
761 | { *len = 0; return NULL; } | |
762 | ||
763 | if (*len > chunking_data_left) *len = chunking_data_left; | |
764 | buf = lwr_receive_getbuf(len); /* Either smtp_getbuf or tls_getbuf */ | |
765 | chunking_data_left -= *len; | |
766 | return buf; | |
767 | } | |
768 | ||
769 | void | |
770 | bdat_flush_data(void) | |
771 | { | |
772 | while (chunking_data_left) | |
773 | { | |
774 | unsigned n = chunking_data_left; | |
775 | if (!bdat_getbuf(&n)) break; | |
776 | } | |
777 | ||
778 | receive_getc = lwr_receive_getc; | |
779 | receive_getbuf = lwr_receive_getbuf; | |
780 | receive_ungetc = lwr_receive_ungetc; | |
781 | ||
782 | if (chunking_state != CHUNKING_LAST) | |
783 | { | |
784 | chunking_state = CHUNKING_OFFERED; | |
785 | DEBUG(D_receive) debug_printf("chunking state %d\n", (int)chunking_state); | |
420a0d19 | 786 | } |
420a0d19 CE |
787 | } |
788 | ||
789 | ||
790 | ||
2ea97746 | 791 | |
420a0d19 CE |
792 | /************************************************* |
793 | * SMTP version of ungetc() * | |
794 | *************************************************/ | |
795 | ||
796 | /* Puts a character back in the input buffer. Only ever | |
797 | called once. | |
798 | ||
799 | Arguments: | |
800 | ch the character | |
801 | ||
802 | Returns: the character | |
803 | */ | |
804 | ||
805 | int | |
806 | smtp_ungetc(int ch) | |
807 | { | |
2ea97746 | 808 | *--smtp_inptr = ch; |
420a0d19 CE |
809 | return ch; |
810 | } | |
811 | ||
812 | ||
2ea97746 CE |
813 | int |
814 | bdat_ungetc(int ch) | |
815 | { | |
816 | chunking_data_left++; | |
817 | return lwr_receive_ungetc(ch); | |
818 | } | |
819 | ||
420a0d19 CE |
820 | |
821 | ||
822 | /************************************************* | |
823 | * SMTP version of feof() * | |
824 | *************************************************/ | |
825 | ||
826 | /* Tests for a previous EOF | |
827 | ||
828 | Arguments: none | |
829 | Returns: non-zero if the eof flag is set | |
830 | */ | |
831 | ||
832 | int | |
833 | smtp_feof(void) | |
834 | { | |
835 | return smtp_had_eof; | |
836 | } | |
837 | ||
838 | ||
839 | ||
840 | ||
841 | /************************************************* | |
842 | * SMTP version of ferror() * | |
843 | *************************************************/ | |
844 | ||
845 | /* Tests for a previous read error, and returns with errno | |
846 | restored to what it was when the error was detected. | |
847 | ||
848 | Arguments: none | |
849 | Returns: non-zero if the error flag is set | |
850 | */ | |
851 | ||
852 | int | |
853 | smtp_ferror(void) | |
854 | { | |
855 | errno = smtp_had_error; | |
856 | return smtp_had_error; | |
857 | } | |
858 | ||
859 | ||
860 | ||
861 | /************************************************* | |
862 | * Test for characters in the SMTP buffer * | |
863 | *************************************************/ | |
864 | ||
865 | /* Used at the end of a message | |
866 | ||
867 | Arguments: none | |
868 | Returns: TRUE/FALSE | |
869 | */ | |
870 | ||
871 | BOOL | |
872 | smtp_buffered(void) | |
873 | { | |
874 | return smtp_inptr < smtp_inend; | |
875 | } | |
876 | ||
877 | ||
878 | ||
879 | /************************************************* | |
880 | * Write formatted string to SMTP channel * | |
881 | *************************************************/ | |
882 | ||
883 | /* This is a separate function so that we don't have to repeat everything for | |
884 | TLS support or debugging. It is global so that the daemon and the | |
885 | authentication functions can use it. It does not return any error indication, | |
886 | because major problems such as dropped connections won't show up till an output | |
887 | flush for non-TLS connections. The smtp_fflush() function is available for | |
888 | checking that: for convenience, TLS output errors are remembered here so that | |
889 | they are also picked up later by smtp_fflush(). | |
890 | ||
891 | Arguments: | |
892 | format format string | |
2ea97746 | 893 | more further data expected |
420a0d19 CE |
894 | ... optional arguments |
895 | ||
896 | Returns: nothing | |
897 | */ | |
898 | ||
899 | void | |
2ea97746 | 900 | smtp_printf(const char *format, BOOL more, ...) |
420a0d19 CE |
901 | { |
902 | va_list ap; | |
903 | ||
2ea97746 CE |
904 | va_start(ap, more); |
905 | smtp_vprintf(format, more, ap); | |
420a0d19 CE |
906 | va_end(ap); |
907 | } | |
908 | ||
909 | /* This is split off so that verify.c:respond_printf() can, in effect, call | |
910 | smtp_printf(), bearing in mind that in C a vararg function can't directly | |
911 | call another vararg function, only a function which accepts a va_list. */ | |
912 | ||
913 | void | |
2ea97746 | 914 | smtp_vprintf(const char *format, BOOL more, va_list ap) |
420a0d19 | 915 | { |
2ea97746 | 916 | gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer }; |
420a0d19 CE |
917 | BOOL yield; |
918 | ||
2ea97746 CE |
919 | yield = !! string_vformat(&gs, FALSE, format, ap); |
920 | string_from_gstring(&gs); | |
420a0d19 CE |
921 | |
922 | DEBUG(D_receive) | |
923 | { | |
924 | void *reset_point = store_get(0); | |
925 | uschar *msg_copy, *cr, *end; | |
2ea97746 CE |
926 | msg_copy = string_copy(gs.s); |
927 | end = msg_copy + gs.ptr; | |
420a0d19 | 928 | while ((cr = Ustrchr(msg_copy, '\r')) != NULL) /* lose CRs */ |
2ea97746 | 929 | memmove(cr, cr + 1, (end--) - cr); |
420a0d19 CE |
930 | debug_printf("SMTP>> %s", msg_copy); |
931 | store_reset(reset_point); | |
932 | } | |
933 | ||
934 | if (!yield) | |
935 | { | |
936 | log_write(0, LOG_MAIN|LOG_PANIC, "string too large in smtp_printf()"); | |
937 | smtp_closedown(US"Unexpected error"); | |
2ea97746 | 938 | exim_exit(EXIT_FAILURE, NULL); |
420a0d19 CE |
939 | } |
940 | ||
941 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs | |
942 | have had the same. Note: this code is also present in smtp_respond(). It would | |
943 | be tidier to have it only in one place, but when it was added, it was easier to | |
944 | do it that way, so as not to have to mess with the code for the RCPT command, | |
945 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
946 | ||
2ea97746 | 947 | if (fl.rcpt_in_progress) |
420a0d19 CE |
948 | { |
949 | if (rcpt_smtp_response == NULL) | |
950 | rcpt_smtp_response = string_copy(big_buffer); | |
2ea97746 | 951 | else if (fl.rcpt_smtp_response_same && |
420a0d19 | 952 | Ustrcmp(rcpt_smtp_response, big_buffer) != 0) |
2ea97746 CE |
953 | fl.rcpt_smtp_response_same = FALSE; |
954 | fl.rcpt_in_progress = FALSE; | |
420a0d19 CE |
955 | } |
956 | ||
957 | /* Now write the string */ | |
958 | ||
959 | #ifdef SUPPORT_TLS | |
2ea97746 | 960 | if (tls_in.active.sock >= 0) |
420a0d19 | 961 | { |
2ea97746 | 962 | if (tls_write(NULL, gs.s, gs.ptr, more) < 0) |
420a0d19 CE |
963 | smtp_write_error = -1; |
964 | } | |
965 | else | |
966 | #endif | |
967 | ||
2ea97746 | 968 | if (fprintf(smtp_out, "%s", gs.s) < 0) smtp_write_error = -1; |
420a0d19 CE |
969 | } |
970 | ||
971 | ||
972 | ||
973 | /************************************************* | |
974 | * Flush SMTP out and check for error * | |
975 | *************************************************/ | |
976 | ||
977 | /* This function isn't currently used within Exim (it detects errors when it | |
978 | tries to read the next SMTP input), but is available for use in local_scan(). | |
979 | For non-TLS connections, it flushes the output and checks for errors. For | |
980 | TLS-connections, it checks for a previously-detected TLS write error. | |
981 | ||
982 | Arguments: none | |
983 | Returns: 0 for no error; -1 after an error | |
984 | */ | |
985 | ||
986 | int | |
987 | smtp_fflush(void) | |
988 | { | |
2ea97746 | 989 | if (tls_in.active.sock < 0 && fflush(smtp_out) != 0) smtp_write_error = -1; |
420a0d19 CE |
990 | return smtp_write_error; |
991 | } | |
992 | ||
993 | ||
994 | ||
995 | /************************************************* | |
996 | * SMTP command read timeout * | |
997 | *************************************************/ | |
998 | ||
999 | /* Signal handler for timing out incoming SMTP commands. This attempts to | |
1000 | finish off tidily. | |
1001 | ||
1002 | Argument: signal number (SIGALRM) | |
1003 | Returns: nothing | |
1004 | */ | |
1005 | ||
1006 | static void | |
1007 | command_timeout_handler(int sig) | |
1008 | { | |
2ea97746 | 1009 | had_command_timeout = sig; |
420a0d19 CE |
1010 | } |
1011 | ||
1012 | ||
1013 | ||
1014 | /************************************************* | |
1015 | * SIGTERM received * | |
1016 | *************************************************/ | |
1017 | ||
1018 | /* Signal handler for handling SIGTERM. Again, try to finish tidily. | |
1019 | ||
1020 | Argument: signal number (SIGTERM) | |
1021 | Returns: nothing | |
1022 | */ | |
1023 | ||
1024 | static void | |
1025 | command_sigterm_handler(int sig) | |
1026 | { | |
2ea97746 | 1027 | had_command_sigterm = sig; |
420a0d19 CE |
1028 | } |
1029 | ||
1030 | ||
1031 | ||
1032 | ||
2ea97746 | 1033 | #ifdef SUPPORT_PROXY |
420a0d19 CE |
1034 | /************************************************* |
1035 | * Restore socket timeout to previous value * | |
1036 | *************************************************/ | |
1037 | /* If the previous value was successfully retrieved, restore | |
1038 | it before returning control to the non-proxy routines | |
1039 | ||
1040 | Arguments: fd - File descriptor for input | |
1041 | get_ok - Successfully retrieved previous values | |
1042 | tvtmp - Time struct with previous values | |
1043 | vslen - Length of time struct | |
1044 | Returns: none | |
1045 | */ | |
1046 | static void | |
2ea97746 | 1047 | restore_socket_timeout(int fd, int get_ok, struct timeval * tvtmp, socklen_t vslen) |
420a0d19 CE |
1048 | { |
1049 | if (get_ok == 0) | |
2ea97746 | 1050 | (void) setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS tvtmp, vslen); |
420a0d19 CE |
1051 | } |
1052 | ||
1053 | /************************************************* | |
1054 | * Check if host is required proxy host * | |
1055 | *************************************************/ | |
1056 | /* The function determines if inbound host will be a regular smtp host | |
2ea97746 CE |
1057 | or if it is configured that it must use Proxy Protocol. A local |
1058 | connection cannot. | |
420a0d19 CE |
1059 | |
1060 | Arguments: none | |
1061 | Returns: bool | |
1062 | */ | |
1063 | ||
1064 | static BOOL | |
1065 | check_proxy_protocol_host() | |
1066 | { | |
1067 | int rc; | |
420a0d19 | 1068 | |
2ea97746 CE |
1069 | if ( sender_host_address |
1070 | && (rc = verify_check_this_host(CUSS &hosts_proxy, NULL, NULL, | |
1071 | sender_host_address, NULL)) == OK) | |
420a0d19 CE |
1072 | { |
1073 | DEBUG(D_receive) | |
1074 | debug_printf("Detected proxy protocol configured host\n"); | |
1075 | proxy_session = TRUE; | |
1076 | } | |
1077 | return proxy_session; | |
1078 | } | |
1079 | ||
1080 | ||
2ea97746 CE |
1081 | /************************************************* |
1082 | * Read data until newline or end of buffer * | |
1083 | *************************************************/ | |
1084 | /* While SMTP is server-speaks-first, TLS is client-speaks-first, so we can't | |
1085 | read an entire buffer and assume there will be nothing past a proxy protocol | |
1086 | header. Our approach normally is to use stdio, but again that relies upon | |
1087 | "STARTTLS\r\n" and a server response before the client starts TLS handshake, or | |
1088 | reading _nothing_ before client TLS handshake. So we don't want to use the | |
1089 | usual buffering reads which may read enough to block TLS starting. | |
1090 | ||
1091 | So unfortunately we're down to "read one byte at a time, with a syscall each, | |
1092 | and expect a little overhead", for all proxy-opened connections which are v1, | |
1093 | just to handle the TLS-on-connect case. Since SSL functions wrap the | |
1094 | underlying fd, we can't assume that we can feed them any already-read content. | |
1095 | ||
1096 | We need to know where to read to, the max capacity, and we'll read until we | |
1097 | get a CR and one more character. Let the caller scream if it's CR+!LF. | |
1098 | ||
1099 | Return the amount read. | |
1100 | */ | |
1101 | ||
1102 | static int | |
1103 | swallow_until_crlf(int fd, uschar *base, int already, int capacity) | |
1104 | { | |
1105 | uschar *to = base + already; | |
1106 | uschar *cr; | |
1107 | int have = 0; | |
1108 | int ret; | |
1109 | int last = 0; | |
1110 | ||
1111 | /* For "PROXY UNKNOWN\r\n" we, at time of writing, expect to have read | |
1112 | up through the \r; for the _normal_ case, we haven't yet seen the \r. */ | |
1113 | ||
1114 | cr = memchr(base, '\r', already); | |
1115 | if (cr != NULL) | |
1116 | { | |
1117 | if ((cr - base) < already - 1) | |
1118 | { | |
1119 | /* \r and presumed \n already within what we have; probably not | |
1120 | actually proxy protocol, but abort cleanly. */ | |
1121 | return 0; | |
1122 | } | |
1123 | /* \r is last character read, just need one more. */ | |
1124 | last = 1; | |
1125 | } | |
1126 | ||
1127 | while (capacity > 0) | |
1128 | { | |
1129 | do { ret = recv(fd, to, 1, 0); } while (ret == -1 && errno == EINTR); | |
1130 | if (ret == -1) | |
1131 | return -1; | |
1132 | have++; | |
1133 | if (last) | |
1134 | return have; | |
1135 | if (*to == '\r') | |
1136 | last = 1; | |
1137 | capacity--; | |
1138 | to++; | |
1139 | } | |
1140 | ||
1141 | /* reached end without having room for a final newline, abort */ | |
1142 | errno = EOVERFLOW; | |
1143 | return -1; | |
1144 | } | |
1145 | ||
420a0d19 CE |
1146 | /************************************************* |
1147 | * Setup host for proxy protocol * | |
1148 | *************************************************/ | |
1149 | /* The function configures the connection based on a header from the | |
1150 | inbound host to use Proxy Protocol. The specification is very exact | |
1151 | so exit with an error if do not find the exact required pieces. This | |
1152 | includes an incorrect number of spaces separating args. | |
1153 | ||
1154 | Arguments: none | |
2ea97746 | 1155 | Returns: Boolean success |
420a0d19 CE |
1156 | */ |
1157 | ||
2ea97746 | 1158 | static void |
420a0d19 CE |
1159 | setup_proxy_protocol_host() |
1160 | { | |
1161 | union { | |
1162 | struct { | |
1163 | uschar line[108]; | |
1164 | } v1; | |
1165 | struct { | |
1166 | uschar sig[12]; | |
1167 | uint8_t ver_cmd; | |
1168 | uint8_t fam; | |
1169 | uint16_t len; | |
1170 | union { | |
1171 | struct { /* TCP/UDP over IPv4, len = 12 */ | |
1172 | uint32_t src_addr; | |
1173 | uint32_t dst_addr; | |
1174 | uint16_t src_port; | |
1175 | uint16_t dst_port; | |
1176 | } ip4; | |
1177 | struct { /* TCP/UDP over IPv6, len = 36 */ | |
1178 | uint8_t src_addr[16]; | |
1179 | uint8_t dst_addr[16]; | |
1180 | uint16_t src_port; | |
1181 | uint16_t dst_port; | |
1182 | } ip6; | |
1183 | struct { /* AF_UNIX sockets, len = 216 */ | |
1184 | uschar src_addr[108]; | |
1185 | uschar dst_addr[108]; | |
1186 | } unx; | |
1187 | } addr; | |
1188 | } v2; | |
1189 | } hdr; | |
1190 | ||
1191 | /* Temp variables used in PPv2 address:port parsing */ | |
1192 | uint16_t tmpport; | |
1193 | char tmpip[INET_ADDRSTRLEN]; | |
1194 | struct sockaddr_in tmpaddr; | |
1195 | char tmpip6[INET6_ADDRSTRLEN]; | |
1196 | struct sockaddr_in6 tmpaddr6; | |
1197 | ||
2ea97746 CE |
1198 | /* We can't read "all data until end" because while SMTP is |
1199 | server-speaks-first, the TLS handshake is client-speaks-first, so for | |
1200 | TLS-on-connect ports the proxy protocol header will usually be immediately | |
1201 | followed by a TLS handshake, and with N TLS libraries, we can't reliably | |
1202 | reinject data for reading by those. So instead we first read "enough to be | |
1203 | safely read within the header, and figure out how much more to read". | |
1204 | For v1 we will later read to the end-of-line, for v2 we will read based upon | |
1205 | the stated length. | |
1206 | ||
1207 | The v2 sig is 12 octets, and another 4 gets us the length, so we know how much | |
1208 | data is needed total. For v1, where the line looks like: | |
1209 | PROXY TCPn L3src L3dest SrcPort DestPort \r\n | |
1210 | ||
1211 | However, for v1 there's also `PROXY UNKNOWN\r\n` which is only 15 octets. | |
1212 | We seem to support that. So, if we read 14 octets then we can tell if we're | |
1213 | v2 or v1. If we're v1, we can continue reading as normal. | |
1214 | ||
1215 | If we're v2, we can't slurp up the entire header. We need the length in the | |
1216 | 15th & 16th octets, then to read everything after that. | |
1217 | ||
1218 | So to safely handle v1 and v2, with client-sent-first supported correctly, | |
1219 | we have to do a minimum of 3 read calls, not 1. Eww. | |
1220 | */ | |
1221 | ||
1222 | #define PROXY_INITIAL_READ 14 | |
1223 | #define PROXY_V2_HEADER_SIZE 16 | |
1224 | #if PROXY_INITIAL_READ > PROXY_V2_HEADER_SIZE | |
1225 | # error Code bug in sizes of data to read for proxy usage | |
1226 | #endif | |
1227 | ||
420a0d19 | 1228 | int get_ok = 0; |
2ea97746 CE |
1229 | int size, ret; |
1230 | int fd = fileno(smtp_in); | |
420a0d19 | 1231 | const char v2sig[12] = "\x0D\x0A\x0D\x0A\x00\x0D\x0A\x51\x55\x49\x54\x0A"; |
2ea97746 | 1232 | uschar * iptype; /* To display debug info */ |
420a0d19 | 1233 | struct timeval tv; |
420a0d19 | 1234 | struct timeval tvtmp; |
2ea97746 CE |
1235 | socklen_t vslen = sizeof(struct timeval); |
1236 | BOOL yield = FALSE; | |
420a0d19 CE |
1237 | |
1238 | /* Save current socket timeout values */ | |
2ea97746 | 1239 | get_ok = getsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tvtmp, &vslen); |
420a0d19 CE |
1240 | |
1241 | /* Proxy Protocol host must send header within a short time | |
1242 | (default 3 seconds) or it's considered invalid */ | |
1243 | tv.tv_sec = PROXY_NEGOTIATION_TIMEOUT_SEC; | |
1244 | tv.tv_usec = PROXY_NEGOTIATION_TIMEOUT_USEC; | |
2ea97746 CE |
1245 | if (setsockopt(fd, SOL_SOCKET, SO_RCVTIMEO, CS &tv, sizeof(tv)) < 0) |
1246 | goto bad; | |
420a0d19 CE |
1247 | |
1248 | do | |
1249 | { | |
1250 | /* The inbound host was declared to be a Proxy Protocol host, so | |
2ea97746 CE |
1251 | don't do a PEEK into the data, actually slurp up enough to be |
1252 | "safe". Can't take it all because TLS-on-connect clients follow | |
1253 | immediately with TLS handshake. */ | |
1254 | ret = recv(fd, &hdr, PROXY_INITIAL_READ, 0); | |
420a0d19 CE |
1255 | } |
1256 | while (ret == -1 && errno == EINTR); | |
1257 | ||
1258 | if (ret == -1) | |
2ea97746 | 1259 | goto proxyfail; |
420a0d19 | 1260 | |
2ea97746 CE |
1261 | /* For v2, handle reading the length, and then the rest. */ |
1262 | if ((ret == PROXY_INITIAL_READ) && (memcmp(&hdr.v2, v2sig, sizeof(v2sig)) == 0)) | |
420a0d19 | 1263 | { |
2ea97746 CE |
1264 | int retmore; |
1265 | uint8_t ver; | |
1266 | ||
1267 | /* First get the length fields. */ | |
1268 | do | |
1269 | { | |
1270 | retmore = recv(fd, (uschar*)&hdr + ret, PROXY_V2_HEADER_SIZE - PROXY_INITIAL_READ, 0); | |
1271 | } while (retmore == -1 && errno == EINTR); | |
1272 | if (retmore == -1) | |
1273 | goto proxyfail; | |
1274 | ret += retmore; | |
420a0d19 | 1275 | |
420a0d19 | 1276 | ver = (hdr.v2.ver_cmd & 0xf0) >> 4; |
2ea97746 CE |
1277 | |
1278 | /* May 2014: haproxy combined the version and command into one byte to | |
1279 | allow two full bytes for the length field in order to proxy SSL | |
1280 | connections. SSL Proxy is not supported in this version of Exim, but | |
1281 | must still separate values here. */ | |
420a0d19 CE |
1282 | |
1283 | if (ver != 0x02) | |
1284 | { | |
1285 | DEBUG(D_receive) debug_printf("Invalid Proxy Protocol version: %d\n", ver); | |
1286 | goto proxyfail; | |
1287 | } | |
2ea97746 | 1288 | |
420a0d19 | 1289 | /* The v2 header will always be 16 bytes per the spec. */ |
2ea97746 CE |
1290 | size = 16 + ntohs(hdr.v2.len); |
1291 | DEBUG(D_receive) debug_printf("Detected PROXYv2 header, size %d (limit %d)\n", | |
1292 | size, (int)sizeof(hdr)); | |
1293 | ||
1294 | /* We should now have 16 octets (PROXY_V2_HEADER_SIZE), and we know the total | |
1295 | amount that we need. Double-check that the size is not unreasonable, then | |
1296 | get the rest. */ | |
1297 | if (size > sizeof(hdr)) | |
420a0d19 | 1298 | { |
2ea97746 | 1299 | DEBUG(D_receive) debug_printf("PROXYv2 header size unreasonably large; security attack?\n"); |
420a0d19 CE |
1300 | goto proxyfail; |
1301 | } | |
2ea97746 CE |
1302 | |
1303 | do | |
1304 | { | |
1305 | do | |
1306 | { | |
1307 | retmore = recv(fd, (uschar*)&hdr + ret, size-ret, 0); | |
1308 | } while (retmore == -1 && errno == EINTR); | |
1309 | if (retmore == -1) | |
1310 | goto proxyfail; | |
1311 | ret += retmore; | |
1312 | DEBUG(D_receive) debug_printf("PROXYv2: have %d/%d required octets\n", ret, size); | |
1313 | } while (ret < size); | |
1314 | ||
1315 | } /* end scope for getting rest of data for v2 */ | |
1316 | ||
1317 | /* At this point: if PROXYv2, we've read the exact size required for all data; | |
1318 | if PROXYv1 then we've read "less than required for any valid line" and should | |
1319 | read the rest". */ | |
1320 | ||
1321 | if (ret >= 16 && memcmp(&hdr.v2, v2sig, 12) == 0) | |
1322 | { | |
1323 | uint8_t cmd = (hdr.v2.ver_cmd & 0x0f); | |
1324 | ||
420a0d19 CE |
1325 | switch (cmd) |
1326 | { | |
1327 | case 0x01: /* PROXY command */ | |
1328 | switch (hdr.v2.fam) | |
1329 | { | |
1330 | case 0x11: /* TCPv4 address type */ | |
1331 | iptype = US"IPv4"; | |
1332 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.src_addr; | |
2ea97746 CE |
1333 | inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip)); |
1334 | if (!string_is_ip_address(US tmpip, NULL)) | |
420a0d19 CE |
1335 | { |
1336 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
2ea97746 | 1337 | goto proxyfail; |
420a0d19 | 1338 | } |
2ea97746 | 1339 | proxy_local_address = sender_host_address; |
420a0d19 CE |
1340 | sender_host_address = string_copy(US tmpip); |
1341 | tmpport = ntohs(hdr.v2.addr.ip4.src_port); | |
2ea97746 | 1342 | proxy_local_port = sender_host_port; |
420a0d19 CE |
1343 | sender_host_port = tmpport; |
1344 | /* Save dest ip/port */ | |
1345 | tmpaddr.sin_addr.s_addr = hdr.v2.addr.ip4.dst_addr; | |
2ea97746 CE |
1346 | inet_ntop(AF_INET, &tmpaddr.sin_addr, CS &tmpip, sizeof(tmpip)); |
1347 | if (!string_is_ip_address(US tmpip, NULL)) | |
420a0d19 CE |
1348 | { |
1349 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
2ea97746 | 1350 | goto proxyfail; |
420a0d19 | 1351 | } |
2ea97746 | 1352 | proxy_external_address = string_copy(US tmpip); |
420a0d19 | 1353 | tmpport = ntohs(hdr.v2.addr.ip4.dst_port); |
2ea97746 | 1354 | proxy_external_port = tmpport; |
420a0d19 CE |
1355 | goto done; |
1356 | case 0x21: /* TCPv6 address type */ | |
1357 | iptype = US"IPv6"; | |
1358 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.src_addr, 16); | |
2ea97746 CE |
1359 | inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6)); |
1360 | if (!string_is_ip_address(US tmpip6, NULL)) | |
420a0d19 CE |
1361 | { |
1362 | DEBUG(D_receive) debug_printf("Invalid %s source IP\n", iptype); | |
2ea97746 | 1363 | goto proxyfail; |
420a0d19 | 1364 | } |
2ea97746 | 1365 | proxy_local_address = sender_host_address; |
420a0d19 CE |
1366 | sender_host_address = string_copy(US tmpip6); |
1367 | tmpport = ntohs(hdr.v2.addr.ip6.src_port); | |
2ea97746 | 1368 | proxy_local_port = sender_host_port; |
420a0d19 CE |
1369 | sender_host_port = tmpport; |
1370 | /* Save dest ip/port */ | |
1371 | memmove(tmpaddr6.sin6_addr.s6_addr, hdr.v2.addr.ip6.dst_addr, 16); | |
2ea97746 CE |
1372 | inet_ntop(AF_INET6, &tmpaddr6.sin6_addr, CS &tmpip6, sizeof(tmpip6)); |
1373 | if (!string_is_ip_address(US tmpip6, NULL)) | |
420a0d19 CE |
1374 | { |
1375 | DEBUG(D_receive) debug_printf("Invalid %s dest port\n", iptype); | |
2ea97746 | 1376 | goto proxyfail; |
420a0d19 | 1377 | } |
2ea97746 | 1378 | proxy_external_address = string_copy(US tmpip6); |
420a0d19 | 1379 | tmpport = ntohs(hdr.v2.addr.ip6.dst_port); |
2ea97746 | 1380 | proxy_external_port = tmpport; |
420a0d19 CE |
1381 | goto done; |
1382 | default: | |
1383 | DEBUG(D_receive) | |
1384 | debug_printf("Unsupported PROXYv2 connection type: 0x%02x\n", | |
1385 | hdr.v2.fam); | |
1386 | goto proxyfail; | |
1387 | } | |
1388 | /* Unsupported protocol, keep local connection address */ | |
1389 | break; | |
1390 | case 0x00: /* LOCAL command */ | |
1391 | /* Keep local connection address for LOCAL */ | |
2ea97746 | 1392 | iptype = US"local"; |
420a0d19 CE |
1393 | break; |
1394 | default: | |
1395 | DEBUG(D_receive) | |
1396 | debug_printf("Unsupported PROXYv2 command: 0x%x\n", cmd); | |
1397 | goto proxyfail; | |
1398 | } | |
1399 | } | |
2ea97746 | 1400 | else if (ret >= 8 && memcmp(hdr.v1.line, "PROXY", 5) == 0) |
420a0d19 | 1401 | { |
2ea97746 CE |
1402 | uschar *p; |
1403 | uschar *end; | |
420a0d19 CE |
1404 | uschar *sp; /* Utility variables follow */ |
1405 | int tmp_port; | |
2ea97746 | 1406 | int r2; |
420a0d19 CE |
1407 | char *endc; |
1408 | ||
2ea97746 CE |
1409 | /* get the rest of the line */ |
1410 | r2 = swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret); | |
1411 | if (r2 == -1) | |
1412 | goto proxyfail; | |
1413 | ret += r2; | |
1414 | ||
1415 | p = string_copy(hdr.v1.line); | |
1416 | end = memchr(p, '\r', ret - 1); | |
1417 | ||
1418 | if (!end || (end == (uschar*)&hdr + ret) || end[1] != '\n') | |
420a0d19 CE |
1419 | { |
1420 | DEBUG(D_receive) debug_printf("Partial or invalid PROXY header\n"); | |
1421 | goto proxyfail; | |
1422 | } | |
1423 | *end = '\0'; /* Terminate the string */ | |
2ea97746 | 1424 | size = end + 2 - p; /* Skip header + CRLF */ |
420a0d19 | 1425 | DEBUG(D_receive) debug_printf("Detected PROXYv1 header\n"); |
2ea97746 | 1426 | DEBUG(D_receive) debug_printf("Bytes read not within PROXY header: %d\n", ret - size); |
420a0d19 | 1427 | /* Step through the string looking for the required fields. Ensure |
2ea97746 | 1428 | strict adherence to required formatting, exit for any error. */ |
420a0d19 CE |
1429 | p += 5; |
1430 | if (!isspace(*(p++))) | |
1431 | { | |
1432 | DEBUG(D_receive) debug_printf("Missing space after PROXY command\n"); | |
1433 | goto proxyfail; | |
1434 | } | |
1435 | if (!Ustrncmp(p, CCS"TCP4", 4)) | |
1436 | iptype = US"IPv4"; | |
1437 | else if (!Ustrncmp(p,CCS"TCP6", 4)) | |
1438 | iptype = US"IPv6"; | |
1439 | else if (!Ustrncmp(p,CCS"UNKNOWN", 7)) | |
1440 | { | |
1441 | iptype = US"Unknown"; | |
1442 | goto done; | |
1443 | } | |
1444 | else | |
1445 | { | |
1446 | DEBUG(D_receive) debug_printf("Invalid TCP type\n"); | |
1447 | goto proxyfail; | |
1448 | } | |
1449 | ||
1450 | p += Ustrlen(iptype); | |
1451 | if (!isspace(*(p++))) | |
1452 | { | |
1453 | DEBUG(D_receive) debug_printf("Missing space after TCP4/6 command\n"); | |
1454 | goto proxyfail; | |
1455 | } | |
1456 | /* Find the end of the arg */ | |
1457 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1458 | { | |
1459 | DEBUG(D_receive) | |
1460 | debug_printf("Did not find proxied src %s\n", iptype); | |
1461 | goto proxyfail; | |
1462 | } | |
1463 | *sp = '\0'; | |
2ea97746 | 1464 | if(!string_is_ip_address(p, NULL)) |
420a0d19 CE |
1465 | { |
1466 | DEBUG(D_receive) | |
1467 | debug_printf("Proxied src arg is not an %s address\n", iptype); | |
1468 | goto proxyfail; | |
1469 | } | |
2ea97746 | 1470 | proxy_local_address = sender_host_address; |
420a0d19 CE |
1471 | sender_host_address = p; |
1472 | p = sp + 1; | |
1473 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1474 | { | |
1475 | DEBUG(D_receive) | |
1476 | debug_printf("Did not find proxy dest %s\n", iptype); | |
1477 | goto proxyfail; | |
1478 | } | |
1479 | *sp = '\0'; | |
2ea97746 | 1480 | if(!string_is_ip_address(p, NULL)) |
420a0d19 CE |
1481 | { |
1482 | DEBUG(D_receive) | |
1483 | debug_printf("Proxy dest arg is not an %s address\n", iptype); | |
1484 | goto proxyfail; | |
1485 | } | |
2ea97746 | 1486 | proxy_external_address = p; |
420a0d19 CE |
1487 | p = sp + 1; |
1488 | if ((sp = Ustrchr(p, ' ')) == NULL) | |
1489 | { | |
1490 | DEBUG(D_receive) debug_printf("Did not find proxied src port\n"); | |
1491 | goto proxyfail; | |
1492 | } | |
1493 | *sp = '\0'; | |
2ea97746 | 1494 | tmp_port = strtol(CCS p, &endc, 10); |
420a0d19 CE |
1495 | if (*endc || tmp_port == 0) |
1496 | { | |
1497 | DEBUG(D_receive) | |
1498 | debug_printf("Proxied src port '%s' not an integer\n", p); | |
1499 | goto proxyfail; | |
1500 | } | |
2ea97746 | 1501 | proxy_local_port = sender_host_port; |
420a0d19 CE |
1502 | sender_host_port = tmp_port; |
1503 | p = sp + 1; | |
1504 | if ((sp = Ustrchr(p, '\0')) == NULL) | |
1505 | { | |
1506 | DEBUG(D_receive) debug_printf("Did not find proxy dest port\n"); | |
1507 | goto proxyfail; | |
1508 | } | |
2ea97746 | 1509 | tmp_port = strtol(CCS p, &endc, 10); |
420a0d19 CE |
1510 | if (*endc || tmp_port == 0) |
1511 | { | |
1512 | DEBUG(D_receive) | |
1513 | debug_printf("Proxy dest port '%s' not an integer\n", p); | |
1514 | goto proxyfail; | |
1515 | } | |
2ea97746 | 1516 | proxy_external_port = tmp_port; |
420a0d19 | 1517 | /* Already checked for /r /n above. Good V1 header received. */ |
420a0d19 CE |
1518 | } |
1519 | else | |
1520 | { | |
1521 | /* Wrong protocol */ | |
1522 | DEBUG(D_receive) debug_printf("Invalid proxy protocol version negotiation\n"); | |
2ea97746 | 1523 | (void) swallow_until_crlf(fd, (uschar*)&hdr, ret, sizeof(hdr)-ret); |
420a0d19 CE |
1524 | goto proxyfail; |
1525 | } | |
1526 | ||
2ea97746 CE |
1527 | done: |
1528 | DEBUG(D_receive) | |
1529 | debug_printf("Valid %s sender from Proxy Protocol header\n", iptype); | |
1530 | yield = proxy_session; | |
1531 | ||
1532 | /* Don't flush any potential buffer contents. Any input on proxyfail | |
1533 | should cause a synchronization failure */ | |
1534 | ||
420a0d19 | 1535 | proxyfail: |
2ea97746 | 1536 | restore_socket_timeout(fd, get_ok, &tvtmp, vslen); |
420a0d19 | 1537 | |
2ea97746 CE |
1538 | bad: |
1539 | if (yield) | |
1540 | { | |
1541 | sender_host_name = NULL; | |
1542 | (void) host_name_lookup(); | |
1543 | host_build_sender_fullhost(); | |
1544 | } | |
1545 | else | |
1546 | { | |
1547 | f.proxy_session_failed = TRUE; | |
1548 | DEBUG(D_receive) | |
1549 | debug_printf("Failure to extract proxied host, only QUIT allowed\n"); | |
1550 | } | |
1551 | ||
1552 | return; | |
420a0d19 CE |
1553 | } |
1554 | #endif | |
1555 | ||
1556 | /************************************************* | |
1557 | * Read one command line * | |
1558 | *************************************************/ | |
1559 | ||
1560 | /* Strictly, SMTP commands coming over the net are supposed to end with CRLF. | |
1561 | There are sites that don't do this, and in any case internal SMTP probably | |
1562 | should check only for LF. Consequently, we check here for LF only. The line | |
1563 | ends up with [CR]LF removed from its end. If we get an overlong line, treat as | |
1564 | an unknown command. The command is read into the global smtp_cmd_buffer so that | |
1565 | it is available via $smtp_command. | |
1566 | ||
1567 | The character reading routine sets up a timeout for each block actually read | |
1568 | from the input (which may contain more than one command). We set up a special | |
1569 | signal handler that closes down the session on a timeout. Control does not | |
1570 | return when it runs. | |
1571 | ||
1572 | Arguments: | |
2ea97746 CE |
1573 | check_sync if TRUE, check synchronization rules if global option is TRUE |
1574 | buffer_lim maximum to buffer in lower layer | |
420a0d19 CE |
1575 | |
1576 | Returns: a code identifying the command (enumerated above) | |
1577 | */ | |
1578 | ||
1579 | static int | |
2ea97746 | 1580 | smtp_read_command(BOOL check_sync, unsigned buffer_lim) |
420a0d19 CE |
1581 | { |
1582 | int c; | |
1583 | int ptr = 0; | |
1584 | smtp_cmd_list *p; | |
1585 | BOOL hadnull = FALSE; | |
1586 | ||
2ea97746 | 1587 | had_command_timeout = 0; |
420a0d19 CE |
1588 | os_non_restarting_signal(SIGALRM, command_timeout_handler); |
1589 | ||
2ea97746 | 1590 | while ((c = (receive_getc)(buffer_lim)) != '\n' && c != EOF) |
420a0d19 | 1591 | { |
2ea97746 | 1592 | if (ptr >= SMTP_CMD_BUFFER_SIZE) |
420a0d19 CE |
1593 | { |
1594 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1595 | return OTHER_CMD; | |
1596 | } | |
1597 | if (c == 0) | |
1598 | { | |
1599 | hadnull = TRUE; | |
1600 | c = '?'; | |
1601 | } | |
1602 | smtp_cmd_buffer[ptr++] = c; | |
1603 | } | |
1604 | ||
1605 | receive_linecount++; /* For BSMTP errors */ | |
1606 | os_non_restarting_signal(SIGALRM, sigalrm_handler); | |
1607 | ||
1608 | /* If hit end of file, return pseudo EOF command. Whether we have a | |
1609 | part-line already read doesn't matter, since this is an error state. */ | |
1610 | ||
1611 | if (c == EOF) return EOF_CMD; | |
1612 | ||
1613 | /* Remove any CR and white space at the end of the line, and terminate the | |
1614 | string. */ | |
1615 | ||
1616 | while (ptr > 0 && isspace(smtp_cmd_buffer[ptr-1])) ptr--; | |
1617 | smtp_cmd_buffer[ptr] = 0; | |
1618 | ||
1619 | DEBUG(D_receive) debug_printf("SMTP<< %s\n", smtp_cmd_buffer); | |
1620 | ||
1621 | /* NULLs are not allowed in SMTP commands */ | |
1622 | ||
1623 | if (hadnull) return BADCHAR_CMD; | |
1624 | ||
1625 | /* Scan command list and return identity, having set the data pointer | |
1626 | to the start of the actual data characters. Check for SMTP synchronization | |
1627 | if required. */ | |
1628 | ||
1629 | for (p = cmd_list; p < cmd_list_end; p++) | |
1630 | { | |
2ea97746 | 1631 | #ifdef SUPPORT_PROXY |
420a0d19 | 1632 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
2ea97746 CE |
1633 | if (proxy_session && f.proxy_session_failed && p->cmd != QUIT_CMD) |
1634 | continue; | |
1635 | #endif | |
1636 | if ( p->len | |
1637 | && strncmpic(smtp_cmd_buffer, US p->name, p->len) == 0 | |
1638 | && ( smtp_cmd_buffer[p->len-1] == ':' /* "mail from:" or "rcpt to:" */ | |
1639 | || smtp_cmd_buffer[p->len] == 0 | |
1640 | || smtp_cmd_buffer[p->len] == ' ' | |
1641 | ) ) | |
420a0d19 CE |
1642 | { |
1643 | if (smtp_inptr < smtp_inend && /* Outstanding input */ | |
1644 | p->cmd < sync_cmd_limit && /* Command should sync */ | |
1645 | check_sync && /* Local flag set */ | |
1646 | smtp_enforce_sync && /* Global flag set */ | |
1647 | sender_host_address != NULL && /* Not local input */ | |
2ea97746 | 1648 | !f.sender_host_notsocket) /* Really is a socket */ |
420a0d19 CE |
1649 | return BADSYN_CMD; |
1650 | ||
1651 | /* The variables $smtp_command and $smtp_command_argument point into the | |
1652 | unmodified input buffer. A copy of the latter is taken for actual | |
1653 | processing, so that it can be chopped up into separate parts if necessary, | |
1654 | for example, when processing a MAIL command options such as SIZE that can | |
1655 | follow the sender address. */ | |
1656 | ||
1657 | smtp_cmd_argument = smtp_cmd_buffer + p->len; | |
1658 | while (isspace(*smtp_cmd_argument)) smtp_cmd_argument++; | |
1659 | Ustrcpy(smtp_data_buffer, smtp_cmd_argument); | |
1660 | smtp_cmd_data = smtp_data_buffer; | |
1661 | ||
1662 | /* Count non-mail commands from those hosts that are controlled in this | |
1663 | way. The default is all hosts. We don't waste effort checking the list | |
1664 | until we get a non-mail command, but then cache the result to save checking | |
1665 | again. If there's a DEFER while checking the host, assume it's in the list. | |
1666 | ||
1667 | Note that one instance of RSET, EHLO/HELO, and STARTTLS is allowed at the | |
1668 | start of each incoming message by fiddling with the value in the table. */ | |
1669 | ||
1670 | if (!p->is_mail_cmd) | |
1671 | { | |
1672 | if (count_nonmail == TRUE_UNSET) count_nonmail = | |
1673 | verify_check_host(&smtp_accept_max_nonmail_hosts) != FAIL; | |
1674 | if (count_nonmail && ++nonmail_command_count > smtp_accept_max_nonmail) | |
1675 | return TOO_MANY_NONMAIL_CMD; | |
1676 | } | |
1677 | ||
1678 | /* If there is data for a command that does not expect it, generate the | |
1679 | error here. */ | |
1680 | ||
1681 | return (p->has_arg || *smtp_cmd_data == 0)? p->cmd : BADARG_CMD; | |
1682 | } | |
1683 | } | |
1684 | ||
2ea97746 | 1685 | #ifdef SUPPORT_PROXY |
420a0d19 | 1686 | /* Only allow QUIT command if Proxy Protocol parsing failed */ |
2ea97746 | 1687 | if (proxy_session && f.proxy_session_failed) |
420a0d19 CE |
1688 | return PROXY_FAIL_IGNORE_CMD; |
1689 | #endif | |
1690 | ||
1691 | /* Enforce synchronization for unknown commands */ | |
1692 | ||
2ea97746 CE |
1693 | if ( smtp_inptr < smtp_inend /* Outstanding input */ |
1694 | && check_sync /* Local flag set */ | |
1695 | && smtp_enforce_sync /* Global flag set */ | |
1696 | && sender_host_address /* Not local input */ | |
1697 | && !f.sender_host_notsocket) /* Really is a socket */ | |
420a0d19 CE |
1698 | return BADSYN_CMD; |
1699 | ||
1700 | return OTHER_CMD; | |
1701 | } | |
1702 | ||
1703 | ||
1704 | ||
420a0d19 CE |
1705 | /************************************************* |
1706 | * Forced closedown of call * | |
1707 | *************************************************/ | |
1708 | ||
1709 | /* This function is called from log.c when Exim is dying because of a serious | |
1710 | disaster, and also from some other places. If an incoming non-batched SMTP | |
1711 | channel is open, it swallows the rest of the incoming message if in the DATA | |
1712 | phase, sends the reply string, and gives an error to all subsequent commands | |
1713 | except QUIT. The existence of an SMTP call is detected by the non-NULLness of | |
1714 | smtp_in. | |
1715 | ||
1716 | Arguments: | |
1717 | message SMTP reply string to send, excluding the code | |
1718 | ||
1719 | Returns: nothing | |
1720 | */ | |
1721 | ||
1722 | void | |
1723 | smtp_closedown(uschar *message) | |
1724 | { | |
2ea97746 | 1725 | if (!smtp_in || smtp_batched_input) return; |
420a0d19 | 1726 | receive_swallow_smtp(); |
2ea97746 | 1727 | smtp_printf("421 %s\r\n", FALSE, message); |
420a0d19 | 1728 | |
2ea97746 | 1729 | for (;;) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) |
420a0d19 | 1730 | { |
2ea97746 | 1731 | case EOF_CMD: |
420a0d19 CE |
1732 | return; |
1733 | ||
2ea97746 CE |
1734 | case QUIT_CMD: |
1735 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); | |
420a0d19 CE |
1736 | mac_smtp_fflush(); |
1737 | return; | |
1738 | ||
2ea97746 CE |
1739 | case RSET_CMD: |
1740 | smtp_printf("250 Reset OK\r\n", FALSE); | |
420a0d19 CE |
1741 | break; |
1742 | ||
2ea97746 CE |
1743 | default: |
1744 | smtp_printf("421 %s\r\n", FALSE, message); | |
420a0d19 | 1745 | break; |
420a0d19 CE |
1746 | } |
1747 | } | |
1748 | ||
1749 | ||
1750 | ||
1751 | ||
1752 | /************************************************* | |
1753 | * Set up connection info for logging * | |
1754 | *************************************************/ | |
1755 | ||
1756 | /* This function is called when logging information about an SMTP connection. | |
1757 | It sets up appropriate source information, depending on the type of connection. | |
1758 | If sender_fullhost is NULL, we are at a very early stage of the connection; | |
1759 | just use the IP address. | |
1760 | ||
1761 | Argument: none | |
1762 | Returns: a string describing the connection | |
1763 | */ | |
1764 | ||
1765 | uschar * | |
1766 | smtp_get_connection_info(void) | |
1767 | { | |
2ea97746 CE |
1768 | const uschar * hostname = sender_fullhost |
1769 | ? sender_fullhost : sender_host_address; | |
420a0d19 CE |
1770 | |
1771 | if (host_checking) | |
1772 | return string_sprintf("SMTP connection from %s", hostname); | |
1773 | ||
2ea97746 | 1774 | if (f.sender_host_unknown || f.sender_host_notsocket) |
420a0d19 CE |
1775 | return string_sprintf("SMTP connection from %s", sender_ident); |
1776 | ||
2ea97746 | 1777 | if (f.is_inetd) |
420a0d19 CE |
1778 | return string_sprintf("SMTP connection from %s (via inetd)", hostname); |
1779 | ||
2ea97746 | 1780 | if (LOGGING(incoming_interface) && interface_address) |
420a0d19 CE |
1781 | return string_sprintf("SMTP connection from %s I=[%s]:%d", hostname, |
1782 | interface_address, interface_port); | |
1783 | ||
1784 | return string_sprintf("SMTP connection from %s", hostname); | |
1785 | } | |
1786 | ||
1787 | ||
1788 | ||
1789 | #ifdef SUPPORT_TLS | |
1790 | /* Append TLS-related information to a log line | |
1791 | ||
1792 | Arguments: | |
2ea97746 | 1793 | g String under construction: allocated string to extend, or NULL |
420a0d19 CE |
1794 | |
1795 | Returns: Allocated string or NULL | |
1796 | */ | |
2ea97746 CE |
1797 | static gstring * |
1798 | s_tlslog(gstring * g) | |
420a0d19 | 1799 | { |
2ea97746 CE |
1800 | if (LOGGING(tls_cipher) && tls_in.cipher) |
1801 | g = string_append(g, 2, US" X=", tls_in.cipher); | |
1802 | if (LOGGING(tls_certificate_verified) && tls_in.cipher) | |
1803 | g = string_append(g, 2, US" CV=", tls_in.certificate_verified? "yes":"no"); | |
1804 | if (LOGGING(tls_peerdn) && tls_in.peerdn) | |
1805 | g = string_append(g, 3, US" DN=\"", string_printing(tls_in.peerdn), US"\""); | |
1806 | if (LOGGING(tls_sni) && tls_in.sni) | |
1807 | g = string_append(g, 3, US" SNI=\"", string_printing(tls_in.sni), US"\""); | |
1808 | return g; | |
420a0d19 CE |
1809 | } |
1810 | #endif | |
1811 | ||
1812 | /************************************************* | |
1813 | * Log lack of MAIL if so configured * | |
1814 | *************************************************/ | |
1815 | ||
1816 | /* This function is called when an SMTP session ends. If the log selector | |
1817 | smtp_no_mail is set, write a log line giving some details of what has happened | |
1818 | in the SMTP session. | |
1819 | ||
1820 | Arguments: none | |
1821 | Returns: nothing | |
1822 | */ | |
1823 | ||
1824 | void | |
1825 | smtp_log_no_mail(void) | |
1826 | { | |
2ea97746 CE |
1827 | int i; |
1828 | uschar * sep, * s; | |
1829 | gstring * g = NULL; | |
420a0d19 | 1830 | |
2ea97746 | 1831 | if (smtp_mailcmd_count > 0 || !LOGGING(smtp_no_mail)) |
420a0d19 CE |
1832 | return; |
1833 | ||
2ea97746 | 1834 | if (sender_host_authenticated) |
420a0d19 | 1835 | { |
2ea97746 CE |
1836 | g = string_append(g, 2, US" A=", sender_host_authenticated); |
1837 | if (authenticated_id) g = string_append(g, 2, US":", authenticated_id); | |
420a0d19 CE |
1838 | } |
1839 | ||
1840 | #ifdef SUPPORT_TLS | |
2ea97746 | 1841 | g = s_tlslog(g); |
420a0d19 CE |
1842 | #endif |
1843 | ||
2ea97746 CE |
1844 | sep = smtp_connection_had[SMTP_HBUFF_SIZE-1] != SCH_NONE ? US" C=..." : US" C="; |
1845 | ||
420a0d19 | 1846 | for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++) |
420a0d19 CE |
1847 | if (smtp_connection_had[i] != SCH_NONE) |
1848 | { | |
2ea97746 | 1849 | g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]); |
420a0d19 CE |
1850 | sep = US","; |
1851 | } | |
420a0d19 CE |
1852 | |
1853 | for (i = 0; i < smtp_ch_index; i++) | |
1854 | { | |
2ea97746 | 1855 | g = string_append(g, 2, sep, smtp_names[smtp_connection_had[i]]); |
420a0d19 CE |
1856 | sep = US","; |
1857 | } | |
1858 | ||
2ea97746 CE |
1859 | if (!(s = string_from_gstring(g))) s = US""; |
1860 | ||
1861 | log_write(0, LOG_MAIN, "no MAIL in %sSMTP connection from %s D=%s%s", | |
1862 | f.tcp_in_fastopen ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO " : US"", | |
1863 | host_and_ident(FALSE), string_timesince(&smtp_connection_start), s); | |
1864 | } | |
1865 | ||
1866 | ||
1867 | /* Return list of recent smtp commands */ | |
1868 | ||
1869 | uschar * | |
1870 | smtp_cmd_hist(void) | |
1871 | { | |
1872 | int i; | |
1873 | gstring * list = NULL; | |
1874 | uschar * s; | |
1875 | ||
1876 | for (i = smtp_ch_index; i < SMTP_HBUFF_SIZE; i++) | |
1877 | if (smtp_connection_had[i] != SCH_NONE) | |
1878 | list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]); | |
1879 | ||
1880 | for (i = 0; i < smtp_ch_index; i++) | |
1881 | list = string_append_listele(list, ',', smtp_names[smtp_connection_had[i]]); | |
1882 | ||
1883 | s = string_from_gstring(list); | |
1884 | return s ? s : US""; | |
420a0d19 CE |
1885 | } |
1886 | ||
1887 | ||
1888 | ||
2ea97746 | 1889 | |
420a0d19 CE |
1890 | /************************************************* |
1891 | * Check HELO line and set sender_helo_name * | |
1892 | *************************************************/ | |
1893 | ||
1894 | /* Check the format of a HELO line. The data for HELO/EHLO is supposed to be | |
1895 | the domain name of the sending host, or an ip literal in square brackets. The | |
2ea97746 | 1896 | argument is placed in sender_helo_name, which is in malloc store, because it |
420a0d19 CE |
1897 | must persist over multiple incoming messages. If helo_accept_junk is set, this |
1898 | host is permitted to send any old junk (needed for some broken hosts). | |
1899 | Otherwise, helo_allow_chars can be used for rogue characters in general | |
1900 | (typically people want to let in underscores). | |
1901 | ||
1902 | Argument: | |
1903 | s the data portion of the line (already past any white space) | |
1904 | ||
1905 | Returns: TRUE or FALSE | |
1906 | */ | |
1907 | ||
1908 | static BOOL | |
1909 | check_helo(uschar *s) | |
1910 | { | |
1911 | uschar *start = s; | |
1912 | uschar *end = s + Ustrlen(s); | |
2ea97746 | 1913 | BOOL yield = fl.helo_accept_junk; |
420a0d19 CE |
1914 | |
1915 | /* Discard any previous helo name */ | |
1916 | ||
2ea97746 | 1917 | if (sender_helo_name) |
420a0d19 CE |
1918 | { |
1919 | store_free(sender_helo_name); | |
1920 | sender_helo_name = NULL; | |
1921 | } | |
1922 | ||
1923 | /* Skip tests if junk is permitted. */ | |
1924 | ||
1925 | if (!yield) | |
2ea97746 | 1926 | |
420a0d19 CE |
1927 | /* Allow the new standard form for IPv6 address literals, namely, |
1928 | [IPv6:....], and because someone is bound to use it, allow an equivalent | |
1929 | IPv4 form. Allow plain addresses as well. */ | |
1930 | ||
1931 | if (*s == '[') | |
1932 | { | |
1933 | if (end[-1] == ']') | |
1934 | { | |
1935 | end[-1] = 0; | |
1936 | if (strncmpic(s, US"[IPv6:", 6) == 0) | |
1937 | yield = (string_is_ip_address(s+6, NULL) == 6); | |
1938 | else if (strncmpic(s, US"[IPv4:", 6) == 0) | |
1939 | yield = (string_is_ip_address(s+6, NULL) == 4); | |
1940 | else | |
1941 | yield = (string_is_ip_address(s+1, NULL) != 0); | |
1942 | end[-1] = ']'; | |
1943 | } | |
1944 | } | |
1945 | ||
1946 | /* Non-literals must be alpha, dot, hyphen, plus any non-valid chars | |
1947 | that have been configured (usually underscore - sigh). */ | |
1948 | ||
2ea97746 CE |
1949 | else if (*s) |
1950 | for (yield = TRUE; *s; s++) | |
420a0d19 CE |
1951 | if (!isalnum(*s) && *s != '.' && *s != '-' && |
1952 | Ustrchr(helo_allow_chars, *s) == NULL) | |
1953 | { | |
1954 | yield = FALSE; | |
1955 | break; | |
1956 | } | |
420a0d19 CE |
1957 | |
1958 | /* Save argument if OK */ | |
1959 | ||
1960 | if (yield) sender_helo_name = string_copy_malloc(start); | |
1961 | return yield; | |
1962 | } | |
1963 | ||
1964 | ||
1965 | ||
1966 | ||
1967 | ||
1968 | /************************************************* | |
1969 | * Extract SMTP command option * | |
1970 | *************************************************/ | |
1971 | ||
1972 | /* This function picks the next option setting off the end of smtp_cmd_data. It | |
1973 | is called for MAIL FROM and RCPT TO commands, to pick off the optional ESMTP | |
1974 | things that can appear there. | |
1975 | ||
1976 | Arguments: | |
1977 | name point this at the name | |
1978 | value point this at the data string | |
1979 | ||
1980 | Returns: TRUE if found an option | |
1981 | */ | |
1982 | ||
1983 | static BOOL | |
1984 | extract_option(uschar **name, uschar **value) | |
1985 | { | |
1986 | uschar *n; | |
1987 | uschar *v = smtp_cmd_data + Ustrlen(smtp_cmd_data) - 1; | |
1988 | while (isspace(*v)) v--; | |
1989 | v[1] = 0; | |
2ea97746 CE |
1990 | while (v > smtp_cmd_data && *v != '=' && !isspace(*v)) |
1991 | { | |
1992 | /* Take care to not stop at a space embedded in a quoted local-part */ | |
1993 | ||
1994 | if (*v == '"') do v--; while (*v != '"' && v > smtp_cmd_data+1); | |
1995 | v--; | |
1996 | } | |
420a0d19 CE |
1997 | |
1998 | n = v; | |
1999 | if (*v == '=') | |
2ea97746 | 2000 | { |
420a0d19 CE |
2001 | while(isalpha(n[-1])) n--; |
2002 | /* RFC says SP, but TAB seen in wild and other major MTAs accept it */ | |
2003 | if (!isspace(n[-1])) return FALSE; | |
2004 | n[-1] = 0; | |
2ea97746 | 2005 | } |
420a0d19 | 2006 | else |
2ea97746 | 2007 | { |
420a0d19 CE |
2008 | n++; |
2009 | if (v == smtp_cmd_data) return FALSE; | |
2ea97746 | 2010 | } |
420a0d19 CE |
2011 | *v++ = 0; |
2012 | *name = n; | |
2013 | *value = v; | |
2014 | return TRUE; | |
2015 | } | |
2016 | ||
2017 | ||
2018 | ||
2019 | ||
2020 | ||
2021 | /************************************************* | |
2022 | * Reset for new message * | |
2023 | *************************************************/ | |
2024 | ||
2025 | /* This function is called whenever the SMTP session is reset from | |
2ea97746 | 2026 | within either of the setup functions; also from the daemon loop. |
420a0d19 CE |
2027 | |
2028 | Argument: the stacking pool storage reset point | |
2029 | Returns: nothing | |
2030 | */ | |
2031 | ||
2ea97746 | 2032 | void |
420a0d19 CE |
2033 | smtp_reset(void *reset_point) |
2034 | { | |
420a0d19 CE |
2035 | recipients_list = NULL; |
2036 | rcpt_count = rcpt_defer_count = rcpt_fail_count = | |
2037 | raw_recipients_count = recipients_count = recipients_list_max = 0; | |
420a0d19 CE |
2038 | message_linecount = 0; |
2039 | message_size = -1; | |
2040 | acl_added_headers = NULL; | |
2041 | acl_removed_headers = NULL; | |
2ea97746 | 2042 | f.queue_only_policy = FALSE; |
420a0d19 | 2043 | rcpt_smtp_response = NULL; |
2ea97746 CE |
2044 | fl.rcpt_smtp_response_same = TRUE; |
2045 | fl.rcpt_in_progress = FALSE; | |
2046 | f.deliver_freeze = FALSE; /* Can be set by ACL */ | |
420a0d19 CE |
2047 | freeze_tell = freeze_tell_config; /* Can be set by ACL */ |
2048 | fake_response = OK; /* Can be set by ACL */ | |
2049 | #ifdef WITH_CONTENT_SCAN | |
2ea97746 | 2050 | f.no_mbox_unspool = FALSE; /* Can be set by ACL */ |
420a0d19 | 2051 | #endif |
2ea97746 CE |
2052 | f.submission_mode = FALSE; /* Can be set by ACL */ |
2053 | f.suppress_local_fixups = f.suppress_local_fixups_default; /* Can be set by ACL */ | |
2054 | f.active_local_from_check = local_from_check; /* Can be set by ACL */ | |
2055 | f.active_local_sender_retain = local_sender_retain; /* Can be set by ACL */ | |
2056 | sending_ip_address = NULL; | |
2057 | return_path = sender_address = NULL; | |
2058 | sender_data = NULL; /* Can be set by ACL */ | |
2059 | deliver_localpart_parent = deliver_localpart_orig = NULL; | |
2060 | deliver_domain_parent = deliver_domain_orig = NULL; | |
2061 | callout_address = NULL; | |
420a0d19 CE |
2062 | submission_name = NULL; /* Can be set by ACL */ |
2063 | raw_sender = NULL; /* After SMTP rewrite, before qualifying */ | |
2064 | sender_address_unrewritten = NULL; /* Set only after verify rewrite */ | |
2065 | sender_verified_list = NULL; /* No senders verified */ | |
2066 | memset(sender_address_cache, 0, sizeof(sender_address_cache)); | |
2067 | memset(sender_domain_cache, 0, sizeof(sender_domain_cache)); | |
2068 | ||
420a0d19 CE |
2069 | authenticated_sender = NULL; |
2070 | #ifdef EXPERIMENTAL_BRIGHTMAIL | |
2071 | bmi_run = 0; | |
2072 | bmi_verdicts = NULL; | |
2073 | #endif | |
2ea97746 CE |
2074 | dnslist_domain = dnslist_matched = NULL; |
2075 | #ifdef SUPPORT_SPF | |
2076 | spf_header_comment = spf_received = spf_result = spf_smtp_comment = NULL; | |
2077 | spf_result_guessed = FALSE; | |
2078 | #endif | |
420a0d19 | 2079 | #ifndef DISABLE_DKIM |
2ea97746 CE |
2080 | dkim_cur_signer = dkim_signers = |
2081 | dkim_signing_domain = dkim_signing_selector = dkim_signatures = NULL; | |
2082 | dkim_cur_signer = dkim_signers = dkim_signing_domain = dkim_signing_selector = NULL; | |
2083 | f.dkim_disable_verify = FALSE; | |
2084 | dkim_collect_input = 0; | |
2085 | dkim_verify_overall = dkim_verify_status = dkim_verify_reason = NULL; | |
2086 | dkim_key_length = 0; | |
2087 | #endif | |
2088 | #ifdef EXPERIMENTAL_DMARC | |
2089 | f.dmarc_has_been_checked = f.dmarc_disable_verify = f.dmarc_enable_forensic = FALSE; | |
2090 | dmarc_domain_policy = dmarc_status = dmarc_status_text = | |
2091 | dmarc_used_domain = NULL; | |
2092 | #endif | |
2093 | #ifdef EXPERIMENTAL_ARC | |
2094 | arc_state = arc_state_reason = NULL; | |
2095 | #endif | |
2096 | dsn_ret = 0; | |
2097 | dsn_envid = NULL; | |
2098 | deliver_host = deliver_host_address = NULL; /* Can be set by ACL */ | |
2099 | #ifndef DISABLE_PRDR | |
2100 | prdr_requested = FALSE; | |
420a0d19 | 2101 | #endif |
2ea97746 CE |
2102 | #ifdef SUPPORT_I18N |
2103 | message_smtputf8 = FALSE; | |
420a0d19 CE |
2104 | #endif |
2105 | body_linecount = body_zerocount = 0; | |
2106 | ||
2107 | sender_rate = sender_rate_limit = sender_rate_period = NULL; | |
2108 | ratelimiters_mail = NULL; /* Updated by ratelimit ACL condition */ | |
2109 | /* Note that ratelimiters_conn persists across resets. */ | |
2110 | ||
2111 | /* Reset message ACL variables */ | |
2112 | ||
2113 | acl_var_m = NULL; | |
2114 | ||
2115 | /* The message body variables use malloc store. They may be set if this is | |
2116 | not the first message in an SMTP session and the previous message caused them | |
2117 | to be referenced in an ACL. */ | |
2118 | ||
2ea97746 | 2119 | if (message_body) |
420a0d19 CE |
2120 | { |
2121 | store_free(message_body); | |
2122 | message_body = NULL; | |
2123 | } | |
2124 | ||
2ea97746 | 2125 | if (message_body_end) |
420a0d19 CE |
2126 | { |
2127 | store_free(message_body_end); | |
2128 | message_body_end = NULL; | |
2129 | } | |
2130 | ||
2131 | /* Warning log messages are also saved in malloc store. They are saved to avoid | |
2132 | repetition in the same message, but it seems right to repeat them for different | |
2133 | messages. */ | |
2134 | ||
2ea97746 | 2135 | while (acl_warn_logged) |
420a0d19 CE |
2136 | { |
2137 | string_item *this = acl_warn_logged; | |
2138 | acl_warn_logged = acl_warn_logged->next; | |
2139 | store_free(this); | |
2140 | } | |
2ea97746 | 2141 | store_reset(reset_point); |
420a0d19 CE |
2142 | } |
2143 | ||
2144 | ||
2145 | ||
2146 | ||
2147 | ||
2148 | /************************************************* | |
2149 | * Initialize for incoming batched SMTP message * | |
2150 | *************************************************/ | |
2151 | ||
2152 | /* This function is called from smtp_setup_msg() in the case when | |
2153 | smtp_batched_input is true. This happens when -bS is used to pass a whole batch | |
2154 | of messages in one file with SMTP commands between them. All errors must be | |
2155 | reported by sending a message, and only MAIL FROM, RCPT TO, and DATA are | |
2156 | relevant. After an error on a sender, or an invalid recipient, the remainder | |
2157 | of the message is skipped. The value of received_protocol is already set. | |
2158 | ||
2159 | Argument: none | |
2160 | Returns: > 0 message successfully started (reached DATA) | |
2161 | = 0 QUIT read or end of file reached | |
2162 | < 0 should not occur | |
2163 | */ | |
2164 | ||
2165 | static int | |
2166 | smtp_setup_batch_msg(void) | |
2167 | { | |
2168 | int done = 0; | |
2169 | void *reset_point = store_get(0); | |
2170 | ||
2171 | /* Save the line count at the start of each transaction - single commands | |
2172 | like HELO and RSET count as whole transactions. */ | |
2173 | ||
2174 | bsmtp_transaction_linecount = receive_linecount; | |
2175 | ||
2176 | if ((receive_feof)()) return 0; /* Treat EOF as QUIT */ | |
2177 | ||
2ea97746 | 2178 | cancel_cutthrough_connection(TRUE, US"smtp_setup_batch_msg"); |
420a0d19 CE |
2179 | smtp_reset(reset_point); /* Reset for start of message */ |
2180 | ||
2181 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
2182 | value. The values are 2 larger than the required yield of the function. */ | |
2183 | ||
2184 | while (done <= 0) | |
2185 | { | |
2186 | uschar *errmess; | |
2187 | uschar *recipient = NULL; | |
2188 | int start, end, sender_domain, recipient_domain; | |
2189 | ||
2ea97746 | 2190 | switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) |
420a0d19 CE |
2191 | { |
2192 | /* The HELO/EHLO commands set sender_address_helo if they have | |
2193 | valid data; otherwise they are ignored, except that they do | |
2194 | a reset of the state. */ | |
2195 | ||
2196 | case HELO_CMD: | |
2197 | case EHLO_CMD: | |
2198 | ||
2ea97746 CE |
2199 | check_helo(smtp_cmd_data); |
2200 | /* Fall through */ | |
420a0d19 CE |
2201 | |
2202 | case RSET_CMD: | |
2ea97746 CE |
2203 | cancel_cutthrough_connection(TRUE, US"RSET received"); |
2204 | smtp_reset(reset_point); | |
2205 | bsmtp_transaction_linecount = receive_linecount; | |
2206 | break; | |
420a0d19 CE |
2207 | |
2208 | ||
2209 | /* The MAIL FROM command requires an address as an operand. All we | |
2210 | do here is to parse it for syntactic correctness. The form "<>" is | |
2211 | a special case which converts into an empty string. The start/end | |
2212 | pointers in the original are not used further for this address, as | |
2213 | it is the canonical extracted address which is all that is kept. */ | |
2214 | ||
2215 | case MAIL_CMD: | |
2ea97746 CE |
2216 | smtp_mailcmd_count++; /* Count for no-mail log */ |
2217 | if (sender_address != NULL) | |
2218 | /* The function moan_smtp_batch() does not return. */ | |
2219 | moan_smtp_batch(smtp_cmd_buffer, "503 Sender already given"); | |
420a0d19 | 2220 | |
2ea97746 CE |
2221 | if (smtp_cmd_data[0] == 0) |
2222 | /* The function moan_smtp_batch() does not return. */ | |
2223 | moan_smtp_batch(smtp_cmd_buffer, "501 MAIL FROM must have an address operand"); | |
420a0d19 | 2224 | |
2ea97746 | 2225 | /* Reset to start of message */ |
420a0d19 | 2226 | |
2ea97746 CE |
2227 | cancel_cutthrough_connection(TRUE, US"MAIL received"); |
2228 | smtp_reset(reset_point); | |
420a0d19 | 2229 | |
2ea97746 | 2230 | /* Apply SMTP rewrite */ |
420a0d19 | 2231 | |
2ea97746 CE |
2232 | raw_sender = ((rewrite_existflags & rewrite_smtp) != 0)? |
2233 | rewrite_one(smtp_cmd_data, rewrite_smtp|rewrite_smtp_sender, NULL, FALSE, | |
2234 | US"", global_rewrite_rules) : smtp_cmd_data; | |
420a0d19 | 2235 | |
2ea97746 | 2236 | /* Extract the address; the TRUE flag allows <> as valid */ |
420a0d19 | 2237 | |
2ea97746 CE |
2238 | raw_sender = |
2239 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
2240 | TRUE); | |
420a0d19 | 2241 | |
2ea97746 CE |
2242 | if (!raw_sender) |
2243 | /* The function moan_smtp_batch() does not return. */ | |
2244 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); | |
420a0d19 | 2245 | |
2ea97746 | 2246 | sender_address = string_copy(raw_sender); |
420a0d19 | 2247 | |
2ea97746 | 2248 | /* Qualify unqualified sender addresses if permitted to do so. */ |
420a0d19 | 2249 | |
2ea97746 CE |
2250 | if ( !sender_domain |
2251 | && sender_address[0] != 0 && sender_address[0] != '@') | |
2252 | if (f.allow_unqualified_sender) | |
2253 | { | |
2254 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
2255 | DEBUG(D_receive) debug_printf("unqualified address %s accepted " | |
2256 | "and rewritten\n", raw_sender); | |
2257 | } | |
2258 | /* The function moan_smtp_batch() does not return. */ | |
2259 | else | |
2260 | moan_smtp_batch(smtp_cmd_buffer, "501 sender address must contain " | |
2261 | "a domain"); | |
2262 | break; | |
420a0d19 CE |
2263 | |
2264 | ||
2265 | /* The RCPT TO command requires an address as an operand. All we do | |
2266 | here is to parse it for syntactic correctness. There may be any number | |
2267 | of RCPT TO commands, specifying multiple senders. We build them all into | |
2268 | a data structure that is in argc/argv format. The start/end values | |
2269 | given by parse_extract_address are not used, as we keep only the | |
2270 | extracted address. */ | |
2271 | ||
2272 | case RCPT_CMD: | |
2ea97746 CE |
2273 | if (!sender_address) |
2274 | /* The function moan_smtp_batch() does not return. */ | |
2275 | moan_smtp_batch(smtp_cmd_buffer, "503 No sender yet given"); | |
2276 | ||
2277 | if (smtp_cmd_data[0] == 0) | |
2278 | /* The function moan_smtp_batch() does not return. */ | |
2279 | moan_smtp_batch(smtp_cmd_buffer, | |
2280 | "501 RCPT TO must have an address operand"); | |
2281 | ||
2282 | /* Check maximum number allowed */ | |
2283 | ||
2284 | if (recipients_max > 0 && recipients_count + 1 > recipients_max) | |
2285 | /* The function moan_smtp_batch() does not return. */ | |
2286 | moan_smtp_batch(smtp_cmd_buffer, "%s too many recipients", | |
2287 | recipients_max_reject? "552": "452"); | |
2288 | ||
2289 | /* Apply SMTP rewrite, then extract address. Don't allow "<>" as a | |
2290 | recipient address */ | |
2291 | ||
2292 | recipient = rewrite_existflags & rewrite_smtp | |
2293 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
2294 | global_rewrite_rules) | |
2295 | : smtp_cmd_data; | |
2296 | ||
2297 | recipient = parse_extract_address(recipient, &errmess, &start, &end, | |
2298 | &recipient_domain, FALSE); | |
2299 | ||
2300 | if (!recipient) | |
2301 | /* The function moan_smtp_batch() does not return. */ | |
2302 | moan_smtp_batch(smtp_cmd_buffer, "501 %s", errmess); | |
2303 | ||
2304 | /* If the recipient address is unqualified, qualify it if permitted. Then | |
2305 | add it to the list of recipients. */ | |
2306 | ||
2307 | if (!recipient_domain) | |
2308 | if (f.allow_unqualified_recipient) | |
2309 | { | |
2310 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
2311 | recipient); | |
2312 | recipient = rewrite_address_qualify(recipient, TRUE); | |
2313 | } | |
2314 | /* The function moan_smtp_batch() does not return. */ | |
2315 | else | |
2316 | moan_smtp_batch(smtp_cmd_buffer, | |
2317 | "501 recipient address must contain a domain"); | |
420a0d19 | 2318 | |
2ea97746 CE |
2319 | receive_add_recipient(recipient, -1); |
2320 | break; | |
420a0d19 CE |
2321 | |
2322 | ||
2323 | /* The DATA command is legal only if it follows successful MAIL FROM | |
2324 | and RCPT TO commands. This function is complete when a valid DATA | |
2325 | command is encountered. */ | |
2326 | ||
2327 | case DATA_CMD: | |
2ea97746 CE |
2328 | if (!sender_address || recipients_count <= 0) |
2329 | /* The function moan_smtp_batch() does not return. */ | |
2330 | if (!sender_address) | |
2331 | moan_smtp_batch(smtp_cmd_buffer, | |
2332 | "503 MAIL FROM:<sender> command must precede DATA"); | |
2333 | else | |
2334 | moan_smtp_batch(smtp_cmd_buffer, | |
2335 | "503 RCPT TO:<recipient> must precede DATA"); | |
420a0d19 | 2336 | else |
2ea97746 CE |
2337 | { |
2338 | done = 3; /* DATA successfully achieved */ | |
2339 | message_ended = END_NOTENDED; /* Indicate in middle of message */ | |
2340 | } | |
2341 | break; | |
420a0d19 CE |
2342 | |
2343 | ||
2344 | /* The VRFY, EXPN, HELP, ETRN, and NOOP commands are ignored. */ | |
2345 | ||
2346 | case VRFY_CMD: | |
2347 | case EXPN_CMD: | |
2348 | case HELP_CMD: | |
2349 | case NOOP_CMD: | |
2350 | case ETRN_CMD: | |
2ea97746 CE |
2351 | bsmtp_transaction_linecount = receive_linecount; |
2352 | break; | |
420a0d19 CE |
2353 | |
2354 | ||
2355 | case EOF_CMD: | |
2356 | case QUIT_CMD: | |
2ea97746 CE |
2357 | done = 2; |
2358 | break; | |
420a0d19 CE |
2359 | |
2360 | ||
2361 | case BADARG_CMD: | |
2ea97746 CE |
2362 | /* The function moan_smtp_batch() does not return. */ |
2363 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected argument data"); | |
2364 | break; | |
420a0d19 CE |
2365 | |
2366 | ||
2367 | case BADCHAR_CMD: | |
2ea97746 CE |
2368 | /* The function moan_smtp_batch() does not return. */ |
2369 | moan_smtp_batch(smtp_cmd_buffer, "501 Unexpected NULL in SMTP command"); | |
2370 | break; | |
420a0d19 CE |
2371 | |
2372 | ||
2373 | default: | |
2ea97746 CE |
2374 | /* The function moan_smtp_batch() does not return. */ |
2375 | moan_smtp_batch(smtp_cmd_buffer, "500 Command unrecognized"); | |
2376 | break; | |
420a0d19 CE |
2377 | } |
2378 | } | |
2379 | ||
2380 | return done - 2; /* Convert yield values */ | |
2381 | } | |
2382 | ||
2383 | ||
2384 | ||
2385 | ||
2ea97746 CE |
2386 | #ifdef SUPPORT_TLS |
2387 | static BOOL | |
2388 | smtp_log_tls_fail(uschar * errstr) | |
2389 | { | |
2390 | uschar * conn_info = smtp_get_connection_info(); | |
420a0d19 | 2391 | |
2ea97746 CE |
2392 | if (Ustrncmp(conn_info, US"SMTP ", 5) == 0) conn_info += 5; |
2393 | /* I'd like to get separated H= here, but too hard for now */ | |
2394 | ||
2395 | log_write(0, LOG_MAIN, "TLS error on %s %s", conn_info, errstr); | |
2396 | return FALSE; | |
2397 | } | |
2398 | #endif | |
2399 | ||
2400 | ||
2401 | ||
2402 | ||
2403 | #ifdef TCP_FASTOPEN | |
2404 | static void | |
2405 | tfo_in_check(void) | |
2406 | { | |
2407 | # ifdef TCP_INFO | |
2408 | struct tcp_info tinfo; | |
2409 | socklen_t len = sizeof(tinfo); | |
2410 | ||
2411 | if (getsockopt(fileno(smtp_out), IPPROTO_TCP, TCP_INFO, &tinfo, &len) == 0) | |
2412 | #ifdef TCPI_OPT_SYN_DATA /* FreeBSD 11 does not seem to have this yet */ | |
2413 | if (tinfo.tcpi_options & TCPI_OPT_SYN_DATA) | |
2414 | { | |
2415 | DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (ACKd data-on-SYN)\n"); | |
2416 | f.tcp_in_fastopen_data = f.tcp_in_fastopen = TRUE; | |
2417 | } | |
2418 | else | |
2419 | #endif | |
2420 | if (tinfo.tcpi_state == TCP_SYN_RECV) | |
2421 | { | |
2422 | DEBUG(D_receive) debug_printf("TCP_FASTOPEN mode connection (state TCP_SYN_RECV)\n"); | |
2423 | f.tcp_in_fastopen = TRUE; | |
2424 | } | |
2425 | # endif | |
2426 | } | |
2427 | #endif | |
2428 | ||
2429 | ||
2430 | /************************************************* | |
2431 | * Start an SMTP session * | |
2432 | *************************************************/ | |
2433 | ||
2434 | /* This function is called at the start of an SMTP session. Thereafter, | |
2435 | smtp_setup_msg() is called to initiate each separate message. This | |
2436 | function does host-specific testing, and outputs the banner line. | |
2437 | ||
2438 | Arguments: none | |
2439 | Returns: FALSE if the session can not continue; something has | |
2440 | gone wrong, or the connection to the host is blocked | |
2441 | */ | |
420a0d19 CE |
2442 | |
2443 | BOOL | |
2444 | smtp_start_session(void) | |
2445 | { | |
2ea97746 | 2446 | int esclen; |
420a0d19 CE |
2447 | uschar *user_msg, *log_msg; |
2448 | uschar *code, *esc; | |
2ea97746 CE |
2449 | uschar *p, *s; |
2450 | gstring * ss; | |
420a0d19 | 2451 | |
2ea97746 | 2452 | gettimeofday(&smtp_connection_start, NULL); |
420a0d19 CE |
2453 | for (smtp_ch_index = 0; smtp_ch_index < SMTP_HBUFF_SIZE; smtp_ch_index++) |
2454 | smtp_connection_had[smtp_ch_index] = SCH_NONE; | |
2455 | smtp_ch_index = 0; | |
2456 | ||
2457 | /* Default values for certain variables */ | |
2458 | ||
2ea97746 | 2459 | fl.helo_seen = fl.esmtp = fl.helo_accept_junk = FALSE; |
420a0d19 CE |
2460 | smtp_mailcmd_count = 0; |
2461 | count_nonmail = TRUE_UNSET; | |
2462 | synprot_error_count = unknown_command_count = nonmail_command_count = 0; | |
2463 | smtp_delay_mail = smtp_rlm_base; | |
2ea97746 CE |
2464 | fl.auth_advertised = FALSE; |
2465 | f.smtp_in_pipelining_advertised = f.smtp_in_pipelining_used = FALSE; | |
2466 | f.pipelining_enable = TRUE; | |
420a0d19 | 2467 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; |
2ea97746 | 2468 | fl.smtp_exit_function_called = FALSE; /* For avoiding loop in not-quit exit */ |
420a0d19 CE |
2469 | |
2470 | /* If receiving by -bs from a trusted user, or testing with -bh, we allow | |
2471 | authentication settings from -oMaa to remain in force. */ | |
2472 | ||
2ea97746 CE |
2473 | if (!host_checking && !f.sender_host_notsocket) |
2474 | sender_host_auth_pubname = sender_host_authenticated = NULL; | |
420a0d19 CE |
2475 | authenticated_by = NULL; |
2476 | ||
2477 | #ifdef SUPPORT_TLS | |
2478 | tls_in.cipher = tls_in.peerdn = NULL; | |
2479 | tls_in.ourcert = tls_in.peercert = NULL; | |
2480 | tls_in.sni = NULL; | |
2481 | tls_in.ocsp = OCSP_NOT_REQ; | |
2ea97746 CE |
2482 | fl.tls_advertised = FALSE; |
2483 | # ifdef EXPERIMENTAL_REQUIRETLS | |
2484 | fl.requiretls_advertised = FALSE; | |
2485 | # endif | |
420a0d19 | 2486 | #endif |
2ea97746 CE |
2487 | fl.dsn_advertised = FALSE; |
2488 | #ifdef SUPPORT_I18N | |
2489 | fl.smtputf8_advertised = FALSE; | |
420a0d19 CE |
2490 | #endif |
2491 | ||
2492 | /* Reset ACL connection variables */ | |
2493 | ||
2494 | acl_var_c = NULL; | |
2495 | ||
2496 | /* Allow for trailing 0 in the command and data buffers. */ | |
2497 | ||
2ea97746 | 2498 | if (!(smtp_cmd_buffer = US malloc(2*SMTP_CMD_BUFFER_SIZE + 2))) |
420a0d19 CE |
2499 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, |
2500 | "malloc() failed for SMTP command buffer"); | |
2ea97746 | 2501 | |
420a0d19 | 2502 | smtp_cmd_buffer[0] = 0; |
2ea97746 | 2503 | smtp_data_buffer = smtp_cmd_buffer + SMTP_CMD_BUFFER_SIZE + 1; |
420a0d19 CE |
2504 | |
2505 | /* For batched input, the protocol setting can be overridden from the | |
2506 | command line by a trusted caller. */ | |
2507 | ||
2508 | if (smtp_batched_input) | |
2509 | { | |
2ea97746 | 2510 | if (!received_protocol) received_protocol = US"local-bsmtp"; |
420a0d19 CE |
2511 | } |
2512 | ||
2513 | /* For non-batched SMTP input, the protocol setting is forced here. It will be | |
2514 | reset later if any of EHLO/AUTH/STARTTLS are received. */ | |
2515 | ||
2516 | else | |
2517 | received_protocol = | |
2ea97746 | 2518 | (sender_host_address ? protocols : protocols_local) [pnormal]; |
420a0d19 CE |
2519 | |
2520 | /* Set up the buffer for inputting using direct read() calls, and arrange to | |
2ea97746 CE |
2521 | call the local functions instead of the standard C ones. Place a NUL at the |
2522 | end of the buffer to safety-stop C-string reads from it. */ | |
420a0d19 | 2523 | |
2ea97746 | 2524 | if (!(smtp_inbuffer = US malloc(IN_BUFFER_SIZE))) |
420a0d19 | 2525 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "malloc() failed for SMTP input buffer"); |
2ea97746 CE |
2526 | smtp_inbuffer[IN_BUFFER_SIZE-1] = '\0'; |
2527 | ||
420a0d19 | 2528 | receive_getc = smtp_getc; |
2ea97746 CE |
2529 | receive_getbuf = smtp_getbuf; |
2530 | receive_get_cache = smtp_get_cache; | |
420a0d19 CE |
2531 | receive_ungetc = smtp_ungetc; |
2532 | receive_feof = smtp_feof; | |
2533 | receive_ferror = smtp_ferror; | |
2534 | receive_smtp_buffered = smtp_buffered; | |
2535 | smtp_inptr = smtp_inend = smtp_inbuffer; | |
2536 | smtp_had_eof = smtp_had_error = 0; | |
2537 | ||
2538 | /* Set up the message size limit; this may be host-specific */ | |
2539 | ||
2540 | thismessage_size_limit = expand_string_integer(message_size_limit, TRUE); | |
2ea97746 | 2541 | if (expand_string_message) |
420a0d19 CE |
2542 | { |
2543 | if (thismessage_size_limit == -1) | |
2544 | log_write(0, LOG_MAIN|LOG_PANIC, "unable to expand message_size_limit: " | |
2545 | "%s", expand_string_message); | |
2546 | else | |
2547 | log_write(0, LOG_MAIN|LOG_PANIC, "invalid message_size_limit: " | |
2548 | "%s", expand_string_message); | |
2549 | smtp_closedown(US"Temporary local problem - please try later"); | |
2550 | return FALSE; | |
2551 | } | |
2552 | ||
2553 | /* When a message is input locally via the -bs or -bS options, sender_host_ | |
2554 | unknown is set unless -oMa was used to force an IP address, in which case it | |
2555 | is checked like a real remote connection. When -bs is used from inetd, this | |
2556 | flag is not set, causing the sending host to be checked. The code that deals | |
2557 | with IP source routing (if configured) is never required for -bs or -bS and | |
2558 | the flag sender_host_notsocket is used to suppress it. | |
2559 | ||
2560 | If smtp_accept_max and smtp_accept_reserve are set, keep some connections in | |
2561 | reserve for certain hosts and/or networks. */ | |
2562 | ||
2ea97746 | 2563 | if (!f.sender_host_unknown) |
420a0d19 CE |
2564 | { |
2565 | int rc; | |
2566 | BOOL reserved_host = FALSE; | |
2567 | ||
2568 | /* Look up IP options (source routing info) on the socket if this is not an | |
2569 | -oMa "host", and if any are found, log them and drop the connection. | |
2570 | ||
2571 | Linux (and others now, see below) is different to everyone else, so there | |
2572 | has to be some conditional compilation here. Versions of Linux before 2.1.15 | |
2573 | used a structure whose name was "options". Somebody finally realized that | |
2574 | this name was silly, and it got changed to "ip_options". I use the | |
2575 | newer name here, but there is a fudge in the script that sets up os.h | |
2576 | to define a macro in older Linux systems. | |
2577 | ||
2578 | Sigh. Linux is a fast-moving target. Another generation of Linux uses | |
2579 | glibc 2, which has chosen ip_opts for the structure name. This is now | |
2580 | really a glibc thing rather than a Linux thing, so the condition name | |
2581 | has been changed to reflect this. It is relevant also to GNU/Hurd. | |
2582 | ||
2583 | Mac OS 10.x (Darwin) is like the later glibc versions, but without the | |
2584 | setting of the __GLIBC__ macro, so we can't detect it automatically. There's | |
2585 | a special macro defined in the os.h file. | |
2586 | ||
2587 | Some DGUX versions on older hardware appear not to support IP options at | |
2588 | all, so there is now a general macro which can be set to cut out this | |
2589 | support altogether. | |
2590 | ||
2591 | How to do this properly in IPv6 is not yet known. */ | |
2592 | ||
2ea97746 | 2593 | #if !HAVE_IPV6 && !defined(NO_IP_OPTIONS) |
420a0d19 CE |
2594 | |
2595 | #ifdef GLIBC_IP_OPTIONS | |
2596 | #if (!defined __GLIBC__) || (__GLIBC__ < 2) | |
2597 | #define OPTSTYLE 1 | |
2598 | #else | |
2599 | #define OPTSTYLE 2 | |
2600 | #endif | |
2601 | #elif defined DARWIN_IP_OPTIONS | |
2602 | #define OPTSTYLE 2 | |
2603 | #else | |
2604 | #define OPTSTYLE 3 | |
2605 | #endif | |
2606 | ||
2ea97746 | 2607 | if (!host_checking && !f.sender_host_notsocket) |
420a0d19 CE |
2608 | { |
2609 | #if OPTSTYLE == 1 | |
2610 | EXIM_SOCKLEN_T optlen = sizeof(struct ip_options) + MAX_IPOPTLEN; | |
2611 | struct ip_options *ipopt = store_get(optlen); | |
2612 | #elif OPTSTYLE == 2 | |
2613 | struct ip_opts ipoptblock; | |
2614 | struct ip_opts *ipopt = &ipoptblock; | |
2615 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); | |
2616 | #else | |
2617 | struct ipoption ipoptblock; | |
2618 | struct ipoption *ipopt = &ipoptblock; | |
2619 | EXIM_SOCKLEN_T optlen = sizeof(ipoptblock); | |
2620 | #endif | |
2621 | ||
2622 | /* Occasional genuine failures of getsockopt() have been seen - for | |
2623 | example, "reset by peer". Therefore, just log and give up on this | |
2624 | call, unless the error is ENOPROTOOPT. This error is given by systems | |
2625 | that have the interfaces but not the mechanism - e.g. GNU/Hurd at the time | |
2626 | of writing. So for that error, carry on - we just can't do an IP options | |
2627 | check. */ | |
2628 | ||
2629 | DEBUG(D_receive) debug_printf("checking for IP options\n"); | |
2630 | ||
2ea97746 | 2631 | if (getsockopt(fileno(smtp_out), IPPROTO_IP, IP_OPTIONS, US (ipopt), |
420a0d19 CE |
2632 | &optlen) < 0) |
2633 | { | |
2634 | if (errno != ENOPROTOOPT) | |
2635 | { | |
2636 | log_write(0, LOG_MAIN, "getsockopt() failed from %s: %s", | |
2637 | host_and_ident(FALSE), strerror(errno)); | |
2ea97746 | 2638 | smtp_printf("451 SMTP service not available\r\n", FALSE); |
420a0d19 CE |
2639 | return FALSE; |
2640 | } | |
2641 | } | |
2642 | ||
2643 | /* Deal with any IP options that are set. On the systems I have looked at, | |
2644 | the value of MAX_IPOPTLEN has been 40, meaning that there should never be | |
2645 | more logging data than will fit in big_buffer. Nevertheless, after somebody | |
2646 | questioned this code, I've added in some paranoid checking. */ | |
2647 | ||
2648 | else if (optlen > 0) | |
2649 | { | |
2650 | uschar *p = big_buffer; | |
2651 | uschar *pend = big_buffer + big_buffer_size; | |
2652 | uschar *opt, *adptr; | |
2653 | int optcount; | |
2654 | struct in_addr addr; | |
2655 | ||
2656 | #if OPTSTYLE == 1 | |
2ea97746 | 2657 | uschar *optstart = US (ipopt->__data); |
420a0d19 | 2658 | #elif OPTSTYLE == 2 |
2ea97746 | 2659 | uschar *optstart = US (ipopt->ip_opts); |
420a0d19 | 2660 | #else |
2ea97746 | 2661 | uschar *optstart = US (ipopt->ipopt_list); |
420a0d19 CE |
2662 | #endif |
2663 | ||
2664 | DEBUG(D_receive) debug_printf("IP options exist\n"); | |
2665 | ||
2666 | Ustrcpy(p, "IP options on incoming call:"); | |
2667 | p += Ustrlen(p); | |
2668 | ||
2669 | for (opt = optstart; opt != NULL && | |
2ea97746 | 2670 | opt < US (ipopt) + optlen;) |
420a0d19 CE |
2671 | { |
2672 | switch (*opt) | |
2673 | { | |
2674 | case IPOPT_EOL: | |
2675 | opt = NULL; | |
2676 | break; | |
2677 | ||
2678 | case IPOPT_NOP: | |
2679 | opt++; | |
2680 | break; | |
2681 | ||
2682 | case IPOPT_SSRR: | |
2683 | case IPOPT_LSRR: | |
2684 | if (!string_format(p, pend-p, " %s [@%s", | |
2685 | (*opt == IPOPT_SSRR)? "SSRR" : "LSRR", | |
2686 | #if OPTSTYLE == 1 | |
2687 | inet_ntoa(*((struct in_addr *)(&(ipopt->faddr)))))) | |
2688 | #elif OPTSTYLE == 2 | |
2689 | inet_ntoa(ipopt->ip_dst))) | |
2690 | #else | |
2691 | inet_ntoa(ipopt->ipopt_dst))) | |
2692 | #endif | |
2693 | { | |
2694 | opt = NULL; | |
2695 | break; | |
2696 | } | |
2697 | ||
2698 | p += Ustrlen(p); | |
2699 | optcount = (opt[1] - 3) / sizeof(struct in_addr); | |
2700 | adptr = opt + 3; | |
2701 | while (optcount-- > 0) | |
2702 | { | |
2703 | memcpy(&addr, adptr, sizeof(addr)); | |
2704 | if (!string_format(p, pend - p - 1, "%s%s", | |
2705 | (optcount == 0)? ":" : "@", inet_ntoa(addr))) | |
2706 | { | |
2707 | opt = NULL; | |
2708 | break; | |
2709 | } | |
2710 | p += Ustrlen(p); | |
2711 | adptr += sizeof(struct in_addr); | |
2712 | } | |
2713 | *p++ = ']'; | |
2714 | opt += opt[1]; | |
2715 | break; | |
2716 | ||
2717 | default: | |
2718 | { | |
2719 | int i; | |
2720 | if (pend - p < 4 + 3*opt[1]) { opt = NULL; break; } | |
2721 | Ustrcat(p, "[ "); | |
2722 | p += 2; | |
2723 | for (i = 0; i < opt[1]; i++) | |
2ea97746 | 2724 | p += sprintf(CS p, "%2.2x ", opt[i]); |
420a0d19 CE |
2725 | *p++ = ']'; |
2726 | } | |
2727 | opt += opt[1]; | |
2728 | break; | |
2729 | } | |
2730 | } | |
2731 | ||
2732 | *p = 0; | |
2733 | log_write(0, LOG_MAIN, "%s", big_buffer); | |
2734 | ||
2735 | /* Refuse any call with IP options. This is what tcpwrappers 7.5 does. */ | |
2736 | ||
2737 | log_write(0, LOG_MAIN|LOG_REJECT, | |
2738 | "connection from %s refused (IP options)", host_and_ident(FALSE)); | |
2739 | ||
2ea97746 | 2740 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
420a0d19 CE |
2741 | return FALSE; |
2742 | } | |
2743 | ||
2744 | /* Length of options = 0 => there are no options */ | |
2745 | ||
2746 | else DEBUG(D_receive) debug_printf("no IP options found\n"); | |
2747 | } | |
2ea97746 | 2748 | #endif /* HAVE_IPV6 && !defined(NO_IP_OPTIONS) */ |
420a0d19 CE |
2749 | |
2750 | /* Set keep-alive in socket options. The option is on by default. This | |
2751 | setting is an attempt to get rid of some hanging connections that stick in | |
2752 | read() when the remote end (usually a dialup) goes away. */ | |
2753 | ||
2ea97746 | 2754 | if (smtp_accept_keepalive && !f.sender_host_notsocket) |
420a0d19 CE |
2755 | ip_keepalive(fileno(smtp_out), sender_host_address, FALSE); |
2756 | ||
2757 | /* If the current host matches host_lookup, set the name by doing a | |
2758 | reverse lookup. On failure, sender_host_name will be NULL and | |
2759 | host_lookup_failed will be TRUE. This may or may not be serious - optional | |
2760 | checks later. */ | |
2761 | ||
2762 | if (verify_check_host(&host_lookup) == OK) | |
2763 | { | |
2764 | (void)host_name_lookup(); | |
2765 | host_build_sender_fullhost(); | |
2766 | } | |
2767 | ||
2768 | /* Delay this until we have the full name, if it is looked up. */ | |
2769 | ||
2770 | set_process_info("handling incoming connection from %s", | |
2771 | host_and_ident(FALSE)); | |
2772 | ||
2ea97746 | 2773 | /* Expand smtp_receive_timeout, if needed */ |
420a0d19 | 2774 | |
2ea97746 CE |
2775 | if (smtp_receive_timeout_s) |
2776 | { | |
2777 | uschar * exp; | |
2778 | if ( !(exp = expand_string(smtp_receive_timeout_s)) | |
2779 | || !(*exp) | |
2780 | || (smtp_receive_timeout = readconf_readtime(exp, 0, FALSE)) < 0 | |
2781 | ) | |
2782 | log_write(0, LOG_MAIN|LOG_PANIC, | |
2783 | "bad value for smtp_receive_timeout: '%s'", exp ? exp : US""); | |
2784 | } | |
420a0d19 CE |
2785 | |
2786 | /* Test for explicit connection rejection */ | |
2787 | ||
2788 | if (verify_check_host(&host_reject_connection) == OK) | |
2789 | { | |
2790 | log_write(L_connection_reject, LOG_MAIN|LOG_REJECT, "refused connection " | |
2791 | "from %s (host_reject_connection)", host_and_ident(FALSE)); | |
2ea97746 | 2792 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
420a0d19 CE |
2793 | return FALSE; |
2794 | } | |
2795 | ||
2796 | /* Test with TCP Wrappers if so configured. There is a problem in that | |
2797 | hosts_ctl() returns 0 (deny) under a number of system failure circumstances, | |
2798 | such as disks dying. In these cases, it is desirable to reject with a 4xx | |
2799 | error instead of a 5xx error. There isn't a "right" way to detect such | |
2800 | problems. The following kludge is used: errno is zeroed before calling | |
2801 | hosts_ctl(). If the result is "reject", a 5xx error is given only if the | |
2802 | value of errno is 0 or ENOENT (which happens if /etc/hosts.{allow,deny} does | |
2803 | not exist). */ | |
2804 | ||
2ea97746 | 2805 | #ifdef USE_TCP_WRAPPERS |
420a0d19 | 2806 | errno = 0; |
2ea97746 | 2807 | if (!(tcp_wrappers_name = expand_string(tcp_wrappers_daemon_name))) |
420a0d19 CE |
2808 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" " |
2809 | "(tcp_wrappers_name) failed: %s", string_printing(tcp_wrappers_name), | |
2810 | expand_string_message); | |
2ea97746 | 2811 | |
420a0d19 | 2812 | if (!hosts_ctl(tcp_wrappers_name, |
2ea97746 CE |
2813 | sender_host_name ? CS sender_host_name : STRING_UNKNOWN, |
2814 | sender_host_address ? CS sender_host_address : STRING_UNKNOWN, | |
2815 | sender_ident ? CS sender_ident : STRING_UNKNOWN)) | |
420a0d19 CE |
2816 | { |
2817 | if (errno == 0 || errno == ENOENT) | |
2818 | { | |
2819 | HDEBUG(D_receive) debug_printf("tcp wrappers rejection\n"); | |
2820 | log_write(L_connection_reject, | |
2821 | LOG_MAIN|LOG_REJECT, "refused connection from %s " | |
2822 | "(tcp wrappers)", host_and_ident(FALSE)); | |
2ea97746 | 2823 | smtp_printf("554 SMTP service not available\r\n", FALSE); |
420a0d19 CE |
2824 | } |
2825 | else | |
2826 | { | |
2827 | int save_errno = errno; | |
2828 | HDEBUG(D_receive) debug_printf("tcp wrappers rejected with unexpected " | |
2829 | "errno value %d\n", save_errno); | |
2830 | log_write(L_connection_reject, | |
2831 | LOG_MAIN|LOG_REJECT, "temporarily refused connection from %s " | |
2832 | "(tcp wrappers errno=%d)", host_and_ident(FALSE), save_errno); | |
2ea97746 | 2833 | smtp_printf("451 Temporary local problem - please try later\r\n", FALSE); |
420a0d19 CE |
2834 | } |
2835 | return FALSE; | |
2836 | } | |
2ea97746 | 2837 | #endif |
420a0d19 CE |
2838 | |
2839 | /* Check for reserved slots. The value of smtp_accept_count has already been | |
2840 | incremented to include this process. */ | |
2841 | ||
2842 | if (smtp_accept_max > 0 && | |
2843 | smtp_accept_count > smtp_accept_max - smtp_accept_reserve) | |
2844 | { | |
2845 | if ((rc = verify_check_host(&smtp_reserve_hosts)) != OK) | |
2846 | { | |
2847 | log_write(L_connection_reject, | |
2848 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2849 | "reserve list: connected=%d max=%d reserve=%d%s", | |
2850 | host_and_ident(FALSE), smtp_accept_count - 1, smtp_accept_max, | |
2851 | smtp_accept_reserve, (rc == DEFER)? " (lookup deferred)" : ""); | |
2852 | smtp_printf("421 %s: Too many concurrent SMTP connections; " | |
2ea97746 | 2853 | "please try again later\r\n", FALSE, smtp_active_hostname); |
420a0d19 CE |
2854 | return FALSE; |
2855 | } | |
2856 | reserved_host = TRUE; | |
2857 | } | |
2858 | ||
2859 | /* If a load level above which only messages from reserved hosts are | |
2860 | accepted is set, check the load. For incoming calls via the daemon, the | |
2861 | check is done in the superior process if there are no reserved hosts, to | |
2862 | save a fork. In all cases, the load average will already be available | |
2863 | in a global variable at this point. */ | |
2864 | ||
2865 | if (smtp_load_reserve >= 0 && | |
2866 | load_average > smtp_load_reserve && | |
2867 | !reserved_host && | |
2868 | verify_check_host(&smtp_reserve_hosts) != OK) | |
2869 | { | |
2870 | log_write(L_connection_reject, | |
2871 | LOG_MAIN, "temporarily refused connection from %s: not in " | |
2872 | "reserve list and load average = %.2f", host_and_ident(FALSE), | |
2873 | (double)load_average/1000.0); | |
2ea97746 | 2874 | smtp_printf("421 %s: Too much load; please try again later\r\n", FALSE, |
420a0d19 CE |
2875 | smtp_active_hostname); |
2876 | return FALSE; | |
2877 | } | |
2878 | ||
2879 | /* Determine whether unqualified senders or recipients are permitted | |
2880 | for this host. Unfortunately, we have to do this every time, in order to | |
2881 | set the flags so that they can be inspected when considering qualifying | |
2882 | addresses in the headers. For a site that permits no qualification, this | |
2883 | won't take long, however. */ | |
2884 | ||
2ea97746 | 2885 | f.allow_unqualified_sender = |
420a0d19 CE |
2886 | verify_check_host(&sender_unqualified_hosts) == OK; |
2887 | ||
2ea97746 | 2888 | f.allow_unqualified_recipient = |
420a0d19 CE |
2889 | verify_check_host(&recipient_unqualified_hosts) == OK; |
2890 | ||
2891 | /* Determine whether HELO/EHLO is required for this host. The requirement | |
2892 | can be hard or soft. */ | |
2893 | ||
2ea97746 CE |
2894 | fl.helo_required = verify_check_host(&helo_verify_hosts) == OK; |
2895 | if (!fl.helo_required) | |
2896 | fl.helo_verify = verify_check_host(&helo_try_verify_hosts) == OK; | |
420a0d19 CE |
2897 | |
2898 | /* Determine whether this hosts is permitted to send syntactic junk | |
2899 | after a HELO or EHLO command. */ | |
2900 | ||
2ea97746 | 2901 | fl.helo_accept_junk = verify_check_host(&helo_accept_junk_hosts) == OK; |
420a0d19 CE |
2902 | } |
2903 | ||
2904 | /* For batch SMTP input we are now done. */ | |
2905 | ||
2906 | if (smtp_batched_input) return TRUE; | |
2907 | ||
420a0d19 CE |
2908 | /* If valid Proxy Protocol source is connecting, set up session. |
2909 | * Failure will not allow any SMTP function other than QUIT. */ | |
2ea97746 CE |
2910 | |
2911 | #ifdef SUPPORT_PROXY | |
420a0d19 | 2912 | proxy_session = FALSE; |
2ea97746 | 2913 | f.proxy_session_failed = FALSE; |
420a0d19 | 2914 | if (check_proxy_protocol_host()) |
2ea97746 CE |
2915 | setup_proxy_protocol_host(); |
2916 | #endif | |
2917 | ||
2918 | /* Start up TLS if tls_on_connect is set. This is for supporting the legacy | |
2919 | smtps port for use with older style SSL MTAs. */ | |
2920 | ||
2921 | #ifdef SUPPORT_TLS | |
2922 | if (tls_in.on_connect) | |
420a0d19 | 2923 | { |
2ea97746 CE |
2924 | if (tls_server_start(tls_require_ciphers, &user_msg) != OK) |
2925 | return smtp_log_tls_fail(user_msg); | |
2926 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; | |
420a0d19 | 2927 | } |
420a0d19 CE |
2928 | #endif |
2929 | ||
2ea97746 | 2930 | /* Run the connect ACL if it exists */ |
420a0d19 CE |
2931 | |
2932 | user_msg = NULL; | |
2ea97746 | 2933 | if (acl_smtp_connect) |
420a0d19 CE |
2934 | { |
2935 | int rc; | |
2ea97746 CE |
2936 | if ((rc = acl_check(ACL_WHERE_CONNECT, NULL, acl_smtp_connect, &user_msg, |
2937 | &log_msg)) != OK) | |
420a0d19 | 2938 | { |
2ea97746 | 2939 | (void) smtp_handle_acl_fail(ACL_WHERE_CONNECT, rc, user_msg, log_msg); |
420a0d19 CE |
2940 | return FALSE; |
2941 | } | |
2942 | } | |
2943 | ||
2944 | /* Output the initial message for a two-way SMTP connection. It may contain | |
2945 | newlines, which then cause a multi-line response to be given. */ | |
2946 | ||
2947 | code = US"220"; /* Default status code */ | |
2948 | esc = US""; /* Default extended status code */ | |
2949 | esclen = 0; /* Length of esc */ | |
2950 | ||
2ea97746 | 2951 | if (!user_msg) |
420a0d19 | 2952 | { |
2ea97746 | 2953 | if (!(s = expand_string(smtp_banner))) |
420a0d19 CE |
2954 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "Expansion of \"%s\" (smtp_banner) " |
2955 | "failed: %s", smtp_banner, expand_string_message); | |
2956 | } | |
2957 | else | |
2958 | { | |
2959 | int codelen = 3; | |
2960 | s = user_msg; | |
2ea97746 | 2961 | smtp_message_code(&code, &codelen, &s, NULL, TRUE); |
420a0d19 CE |
2962 | if (codelen > 4) |
2963 | { | |
2964 | esc = code + 4; | |
2965 | esclen = codelen - 4; | |
2966 | } | |
2967 | } | |
2968 | ||
2969 | /* Remove any terminating newlines; might as well remove trailing space too */ | |
2970 | ||
2971 | p = s + Ustrlen(s); | |
2972 | while (p > s && isspace(p[-1])) p--; | |
2973 | *p = 0; | |
2974 | ||
2975 | /* It seems that CC:Mail is braindead, and assumes that the greeting message | |
2976 | is all contained in a single IP packet. The original code wrote out the | |
2977 | greeting using several calls to fprint/fputc, and on busy servers this could | |
2978 | cause it to be split over more than one packet - which caused CC:Mail to fall | |
2979 | over when it got the second part of the greeting after sending its first | |
2980 | command. Sigh. To try to avoid this, build the complete greeting message | |
2981 | first, and output it in one fell swoop. This gives a better chance of it | |
2982 | ending up as a single packet. */ | |
2983 | ||
2ea97746 | 2984 | ss = string_get(256); |
420a0d19 CE |
2985 | |
2986 | p = s; | |
2987 | do /* At least once, in case we have an empty string */ | |
2988 | { | |
2989 | int len; | |
2990 | uschar *linebreak = Ustrchr(p, '\n'); | |
2ea97746 CE |
2991 | ss = string_catn(ss, code, 3); |
2992 | if (!linebreak) | |
420a0d19 CE |
2993 | { |
2994 | len = Ustrlen(p); | |
2ea97746 | 2995 | ss = string_catn(ss, US" ", 1); |
420a0d19 CE |
2996 | } |
2997 | else | |
2998 | { | |
2999 | len = linebreak - p; | |
2ea97746 | 3000 | ss = string_catn(ss, US"-", 1); |
420a0d19 | 3001 | } |
2ea97746 CE |
3002 | ss = string_catn(ss, esc, esclen); |
3003 | ss = string_catn(ss, p, len); | |
3004 | ss = string_catn(ss, US"\r\n", 2); | |
420a0d19 | 3005 | p += len; |
2ea97746 | 3006 | if (linebreak) p++; |
420a0d19 | 3007 | } |
2ea97746 | 3008 | while (*p); |
420a0d19 CE |
3009 | |
3010 | /* Before we write the banner, check that there is no input pending, unless | |
3011 | this synchronisation check is disabled. */ | |
3012 | ||
2ea97746 CE |
3013 | #ifdef EXPERIMENTAL_PIPE_CONNECT |
3014 | fl.pipe_connect_acceptable = | |
3015 | sender_host_address && verify_check_host(&pipe_connect_advertise_hosts) == OK; | |
3016 | ||
420a0d19 | 3017 | if (!check_sync()) |
2ea97746 CE |
3018 | if (fl.pipe_connect_acceptable) |
3019 | f.smtp_in_early_pipe_used = TRUE; | |
3020 | else | |
3021 | #else | |
3022 | if (!check_sync()) | |
3023 | #endif | |
3024 | { | |
3025 | unsigned n = smtp_inend - smtp_inptr; | |
3026 | if (n > 32) n = 32; | |
3027 | ||
3028 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol " | |
3029 | "synchronization error (input sent without waiting for greeting): " | |
3030 | "rejected connection from %s input=\"%s\"", host_and_ident(TRUE), | |
3031 | string_printing(string_copyn(smtp_inptr, n))); | |
3032 | smtp_printf("554 SMTP synchronization error\r\n", FALSE); | |
3033 | return FALSE; | |
3034 | } | |
420a0d19 CE |
3035 | |
3036 | /* Now output the banner */ | |
2ea97746 CE |
3037 | /*XXX the ehlo-resp code does its own tls/nontls bit. Maybe subroutine that? */ |
3038 | ||
3039 | smtp_printf("%s", | |
3040 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
3041 | fl.pipe_connect_acceptable && pipeline_connect_sends(), | |
3042 | #else | |
3043 | FALSE, | |
3044 | #endif | |
3045 | string_from_gstring(ss)); | |
3046 | ||
3047 | /* Attempt to see if we sent the banner before the last ACK of the 3-way | |
3048 | handshake arrived. If so we must have managed a TFO. */ | |
3049 | ||
3050 | #ifdef TCP_FASTOPEN | |
3051 | tfo_in_check(); | |
3052 | #endif | |
420a0d19 | 3053 | |
420a0d19 CE |
3054 | return TRUE; |
3055 | } | |
3056 | ||
3057 | ||
3058 | ||
3059 | ||
3060 | ||
3061 | /************************************************* | |
3062 | * Handle SMTP syntax and protocol errors * | |
3063 | *************************************************/ | |
3064 | ||
3065 | /* Write to the log for SMTP syntax errors in incoming commands, if configured | |
3066 | to do so. Then transmit the error response. The return value depends on the | |
3067 | number of syntax and protocol errors in this SMTP session. | |
3068 | ||
3069 | Arguments: | |
3070 | type error type, given as a log flag bit | |
3071 | code response code; <= 0 means don't send a response | |
3072 | data data to reflect in the response (can be NULL) | |
3073 | errmess the error message | |
3074 | ||
3075 | Returns: -1 limit of syntax/protocol errors NOT exceeded | |
3076 | +1 limit of syntax/protocol errors IS exceeded | |
3077 | ||
3078 | These values fit in with the values of the "done" variable in the main | |
3079 | processing loop in smtp_setup_msg(). */ | |
3080 | ||
3081 | static int | |
3082 | synprot_error(int type, int code, uschar *data, uschar *errmess) | |
3083 | { | |
3084 | int yield = -1; | |
3085 | ||
3086 | log_write(type, LOG_MAIN, "SMTP %s error in \"%s\" %s %s", | |
3087 | (type == L_smtp_syntax_error)? "syntax" : "protocol", | |
3088 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), errmess); | |
3089 | ||
3090 | if (++synprot_error_count > smtp_max_synprot_errors) | |
3091 | { | |
3092 | yield = 1; | |
3093 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
3094 | "syntax or protocol errors (last command was \"%s\")", | |
2ea97746 | 3095 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); |
420a0d19 CE |
3096 | } |
3097 | ||
3098 | if (code > 0) | |
3099 | { | |
2ea97746 CE |
3100 | smtp_printf("%d%c%s%s%s\r\n", FALSE, code, yield == 1 ? '-' : ' ', |
3101 | data ? data : US"", data ? US": " : US"", errmess); | |
420a0d19 | 3102 | if (yield == 1) |
2ea97746 | 3103 | smtp_printf("%d Too many syntax or protocol errors\r\n", FALSE, code); |
420a0d19 CE |
3104 | } |
3105 | ||
3106 | return yield; | |
3107 | } | |
3108 | ||
3109 | ||
3110 | ||
3111 | ||
420a0d19 CE |
3112 | /************************************************* |
3113 | * Send SMTP response, possibly multiline * | |
3114 | *************************************************/ | |
3115 | ||
3116 | /* There are, it seems, broken clients out there that cannot handle multiline | |
3117 | responses. If no_multiline_responses is TRUE (it can be set from an ACL), we | |
3118 | output nothing for non-final calls, and only the first line for anything else. | |
3119 | ||
3120 | Arguments: | |
3121 | code SMTP code, may involve extended status codes | |
3122 | codelen length of smtp code; if > 4 there's an ESC | |
3123 | final FALSE if the last line isn't the final line | |
3124 | msg message text, possibly containing newlines | |
3125 | ||
3126 | Returns: nothing | |
3127 | */ | |
3128 | ||
3129 | void | |
3130 | smtp_respond(uschar* code, int codelen, BOOL final, uschar *msg) | |
3131 | { | |
3132 | int esclen = 0; | |
3133 | uschar *esc = US""; | |
3134 | ||
2ea97746 | 3135 | if (!final && f.no_multiline_responses) return; |
420a0d19 CE |
3136 | |
3137 | if (codelen > 4) | |
3138 | { | |
3139 | esc = code + 4; | |
3140 | esclen = codelen - 4; | |
3141 | } | |
3142 | ||
3143 | /* If this is the first output for a (non-batch) RCPT command, see if all RCPTs | |
3144 | have had the same. Note: this code is also present in smtp_printf(). It would | |
3145 | be tidier to have it only in one place, but when it was added, it was easier to | |
3146 | do it that way, so as not to have to mess with the code for the RCPT command, | |
3147 | which sometimes uses smtp_printf() and sometimes smtp_respond(). */ | |
3148 | ||
2ea97746 | 3149 | if (fl.rcpt_in_progress) |
420a0d19 CE |
3150 | { |
3151 | if (rcpt_smtp_response == NULL) | |
3152 | rcpt_smtp_response = string_copy(msg); | |
2ea97746 | 3153 | else if (fl.rcpt_smtp_response_same && |
420a0d19 | 3154 | Ustrcmp(rcpt_smtp_response, msg) != 0) |
2ea97746 CE |
3155 | fl.rcpt_smtp_response_same = FALSE; |
3156 | fl.rcpt_in_progress = FALSE; | |
420a0d19 CE |
3157 | } |
3158 | ||
2ea97746 CE |
3159 | /* Now output the message, splitting it up into multiple lines if necessary. |
3160 | We only handle pipelining these responses as far as nonfinal/final groups, | |
3161 | not the whole MAIL/RCPT/DATA response set. */ | |
420a0d19 CE |
3162 | |
3163 | for (;;) | |
3164 | { | |
3165 | uschar *nl = Ustrchr(msg, '\n'); | |
3166 | if (nl == NULL) | |
3167 | { | |
2ea97746 | 3168 | smtp_printf("%.3s%c%.*s%s\r\n", !final, code, final ? ' ':'-', esclen, esc, msg); |
420a0d19 CE |
3169 | return; |
3170 | } | |
2ea97746 | 3171 | else if (nl[1] == 0 || f.no_multiline_responses) |
420a0d19 | 3172 | { |
2ea97746 | 3173 | smtp_printf("%.3s%c%.*s%.*s\r\n", !final, code, final ? ' ':'-', esclen, esc, |
420a0d19 CE |
3174 | (int)(nl - msg), msg); |
3175 | return; | |
3176 | } | |
3177 | else | |
3178 | { | |
2ea97746 | 3179 | smtp_printf("%.3s-%.*s%.*s\r\n", TRUE, code, esclen, esc, (int)(nl - msg), msg); |
420a0d19 CE |
3180 | msg = nl + 1; |
3181 | while (isspace(*msg)) msg++; | |
3182 | } | |
3183 | } | |
3184 | } | |
3185 | ||
3186 | ||
3187 | ||
3188 | ||
3189 | /************************************************* | |
3190 | * Parse user SMTP message * | |
3191 | *************************************************/ | |
3192 | ||
3193 | /* This function allows for user messages overriding the response code details | |
3194 | by providing a suitable response code string at the start of the message | |
3195 | user_msg. Check the message for starting with a response code and optionally an | |
3196 | extended status code. If found, check that the first digit is valid, and if so, | |
3197 | change the code pointer and length to use the replacement. An invalid code | |
3198 | causes a panic log; in this case, if the log messages is the same as the user | |
3199 | message, we must also adjust the value of the log message to show the code that | |
3200 | is actually going to be used (the original one). | |
3201 | ||
3202 | This function is global because it is called from receive.c as well as within | |
3203 | this module. | |
3204 | ||
3205 | Note that the code length returned includes the terminating whitespace | |
3206 | character, which is always included in the regex match. | |
3207 | ||
3208 | Arguments: | |
3209 | code SMTP code, may involve extended status codes | |
3210 | codelen length of smtp code; if > 4 there's an ESC | |
3211 | msg message text | |
3212 | log_msg optional log message, to be adjusted with the new SMTP code | |
2ea97746 | 3213 | check_valid if true, verify the response code |
420a0d19 CE |
3214 | |
3215 | Returns: nothing | |
3216 | */ | |
3217 | ||
3218 | void | |
2ea97746 CE |
3219 | smtp_message_code(uschar **code, int *codelen, uschar **msg, uschar **log_msg, |
3220 | BOOL check_valid) | |
420a0d19 CE |
3221 | { |
3222 | int n; | |
3223 | int ovector[3]; | |
3224 | ||
2ea97746 | 3225 | if (!msg || !*msg) return; |
420a0d19 | 3226 | |
2ea97746 CE |
3227 | if ((n = pcre_exec(regex_smtp_code, NULL, CS *msg, Ustrlen(*msg), 0, |
3228 | PCRE_EOPT, ovector, sizeof(ovector)/sizeof(int))) < 0) return; | |
420a0d19 | 3229 | |
2ea97746 | 3230 | if (check_valid && (*msg)[0] != (*code)[0]) |
420a0d19 CE |
3231 | { |
3232 | log_write(0, LOG_MAIN|LOG_PANIC, "configured error code starts with " | |
3233 | "incorrect digit (expected %c) in \"%s\"", (*code)[0], *msg); | |
3234 | if (log_msg != NULL && *log_msg == *msg) | |
3235 | *log_msg = string_sprintf("%s %s", *code, *log_msg + ovector[1]); | |
3236 | } | |
3237 | else | |
3238 | { | |
3239 | *code = *msg; | |
3240 | *codelen = ovector[1]; /* Includes final space */ | |
3241 | } | |
3242 | *msg += ovector[1]; /* Chop the code off the message */ | |
3243 | return; | |
3244 | } | |
3245 | ||
3246 | ||
3247 | ||
3248 | ||
3249 | /************************************************* | |
3250 | * Handle an ACL failure * | |
3251 | *************************************************/ | |
3252 | ||
3253 | /* This function is called when acl_check() fails. As well as calls from within | |
3254 | this module, it is called from receive.c for an ACL after DATA. It sorts out | |
2ea97746 | 3255 | logging the incident, and sends the error response. A message containing |
420a0d19 CE |
3256 | newlines is turned into a multiline SMTP response, but for logging, only the |
3257 | first line is used. | |
3258 | ||
3259 | There's a table of default permanent failure response codes to use in | |
3260 | globals.c, along with the table of names. VFRY is special. Despite RFC1123 it | |
3261 | defaults disabled in Exim. However, discussion in connection with RFC 821bis | |
3262 | (aka RFC 2821) has concluded that the response should be 252 in the disabled | |
3263 | state, because there are broken clients that try VRFY before RCPT. A 5xx | |
3264 | response should be given only when the address is positively known to be | |
2ea97746 CE |
3265 | undeliverable. Sigh. We return 252 if there is no VRFY ACL or it provides |
3266 | no explicit code, but if there is one we let it know best. | |
3267 | Also, for ETRN, 458 is given on refusal, and for AUTH, 503. | |
420a0d19 CE |
3268 | |
3269 | From Exim 4.63, it is possible to override the response code details by | |
3270 | providing a suitable response code string at the start of the message provided | |
3271 | in user_msg. The code's first digit is checked for validity. | |
3272 | ||
3273 | Arguments: | |
2ea97746 CE |
3274 | where where the ACL was called from |
3275 | rc the failure code | |
3276 | user_msg a message that can be included in an SMTP response | |
3277 | log_msg a message for logging | |
420a0d19 CE |
3278 | |
3279 | Returns: 0 in most cases | |
3280 | 2 if the failure code was FAIL_DROP, in which case the | |
3281 | SMTP connection should be dropped (this value fits with the | |
3282 | "done" variable in smtp_setup_msg() below) | |
3283 | */ | |
3284 | ||
3285 | int | |
3286 | smtp_handle_acl_fail(int where, int rc, uschar *user_msg, uschar *log_msg) | |
3287 | { | |
3288 | BOOL drop = rc == FAIL_DROP; | |
3289 | int codelen = 3; | |
3290 | uschar *smtp_code; | |
3291 | uschar *lognl; | |
3292 | uschar *sender_info = US""; | |
3293 | uschar *what = | |
3294 | #ifdef WITH_CONTENT_SCAN | |
2ea97746 | 3295 | where == ACL_WHERE_MIME ? US"during MIME ACL checks" : |
420a0d19 | 3296 | #endif |
2ea97746 CE |
3297 | where == ACL_WHERE_PREDATA ? US"DATA" : |
3298 | where == ACL_WHERE_DATA ? US"after DATA" : | |
420a0d19 | 3299 | #ifndef DISABLE_PRDR |
2ea97746 | 3300 | where == ACL_WHERE_PRDR ? US"after DATA PRDR" : |
420a0d19 | 3301 | #endif |
2ea97746 CE |
3302 | smtp_cmd_data ? |
3303 | string_sprintf("%s %s", acl_wherenames[where], smtp_cmd_data) : | |
3304 | string_sprintf("%s in \"connect\" ACL", acl_wherenames[where]); | |
420a0d19 CE |
3305 | |
3306 | if (drop) rc = FAIL; | |
3307 | ||
3308 | /* Set the default SMTP code, and allow a user message to change it. */ | |
3309 | ||
2ea97746 CE |
3310 | smtp_code = rc == FAIL ? acl_wherecodes[where] : US"451"; |
3311 | smtp_message_code(&smtp_code, &codelen, &user_msg, &log_msg, | |
3312 | where != ACL_WHERE_VRFY); | |
420a0d19 CE |
3313 | |
3314 | /* We used to have sender_address here; however, there was a bug that was not | |
3315 | updating sender_address after a rewrite during a verify. When this bug was | |
3316 | fixed, sender_address at this point became the rewritten address. I'm not sure | |
3317 | this is what should be logged, so I've changed to logging the unrewritten | |
3318 | address to retain backward compatibility. */ | |
3319 | ||
3320 | #ifndef WITH_CONTENT_SCAN | |
3321 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA) | |
3322 | #else | |
3323 | if (where == ACL_WHERE_RCPT || where == ACL_WHERE_DATA || where == ACL_WHERE_MIME) | |
3324 | #endif | |
3325 | { | |
3326 | sender_info = string_sprintf("F=<%s>%s%s%s%s ", | |
3327 | sender_address_unrewritten ? sender_address_unrewritten : sender_address, | |
3328 | sender_host_authenticated ? US" A=" : US"", | |
3329 | sender_host_authenticated ? sender_host_authenticated : US"", | |
3330 | sender_host_authenticated && authenticated_id ? US":" : US"", | |
3331 | sender_host_authenticated && authenticated_id ? authenticated_id : US"" | |
3332 | ); | |
3333 | } | |
3334 | ||
3335 | /* If there's been a sender verification failure with a specific message, and | |
3336 | we have not sent a response about it yet, do so now, as a preliminary line for | |
3337 | failures, but not defers. However, always log it for defer, and log it for fail | |
3338 | unless the sender_verify_fail log selector has been turned off. */ | |
3339 | ||
2ea97746 | 3340 | if (sender_verified_failed && |
420a0d19 CE |
3341 | !testflag(sender_verified_failed, af_sverify_told)) |
3342 | { | |
2ea97746 CE |
3343 | BOOL save_rcpt_in_progress = fl.rcpt_in_progress; |
3344 | fl.rcpt_in_progress = FALSE; /* So as not to treat these as the error */ | |
420a0d19 CE |
3345 | |
3346 | setflag(sender_verified_failed, af_sverify_told); | |
3347 | ||
2ea97746 | 3348 | if (rc != FAIL || LOGGING(sender_verify_fail)) |
420a0d19 CE |
3349 | log_write(0, LOG_MAIN|LOG_REJECT, "%s sender verify %s for <%s>%s", |
3350 | host_and_ident(TRUE), | |
3351 | ((sender_verified_failed->special_action & 255) == DEFER)? "defer":"fail", | |
3352 | sender_verified_failed->address, | |
3353 | (sender_verified_failed->message == NULL)? US"" : | |
3354 | string_sprintf(": %s", sender_verified_failed->message)); | |
3355 | ||
2ea97746 | 3356 | if (rc == FAIL && sender_verified_failed->user_message) |
420a0d19 CE |
3357 | smtp_respond(smtp_code, codelen, FALSE, string_sprintf( |
3358 | testflag(sender_verified_failed, af_verify_pmfail)? | |
3359 | "Postmaster verification failed while checking <%s>\n%s\n" | |
3360 | "Several RFCs state that you are required to have a postmaster\n" | |
3361 | "mailbox for each mail domain. This host does not accept mail\n" | |
3362 | "from domains whose servers reject the postmaster address." | |
3363 | : | |
3364 | testflag(sender_verified_failed, af_verify_nsfail)? | |
3365 | "Callback setup failed while verifying <%s>\n%s\n" | |
3366 | "The initial connection, or a HELO or MAIL FROM:<> command was\n" | |
3367 | "rejected. Refusing MAIL FROM:<> does not help fight spam, disregards\n" | |
3368 | "RFC requirements, and stops you from receiving standard bounce\n" | |
3369 | "messages. This host does not accept mail from domains whose servers\n" | |
3370 | "refuse bounces." | |
3371 | : | |
3372 | "Verification failed for <%s>\n%s", | |
3373 | sender_verified_failed->address, | |
3374 | sender_verified_failed->user_message)); | |
3375 | ||
2ea97746 | 3376 | fl.rcpt_in_progress = save_rcpt_in_progress; |
420a0d19 CE |
3377 | } |
3378 | ||
3379 | /* Sort out text for logging */ | |
3380 | ||
2ea97746 CE |
3381 | log_msg = log_msg ? string_sprintf(": %s", log_msg) : US""; |
3382 | if ((lognl = Ustrchr(log_msg, '\n'))) *lognl = 0; | |
420a0d19 CE |
3383 | |
3384 | /* Send permanent failure response to the command, but the code used isn't | |
3385 | always a 5xx one - see comments at the start of this function. If the original | |
3386 | rc was FAIL_DROP we drop the connection and yield 2. */ | |
3387 | ||
2ea97746 CE |
3388 | if (rc == FAIL) |
3389 | smtp_respond(smtp_code, codelen, TRUE, | |
3390 | user_msg ? user_msg : US"Administrative prohibition"); | |
420a0d19 CE |
3391 | |
3392 | /* Send temporary failure response to the command. Don't give any details, | |
3393 | unless acl_temp_details is set. This is TRUE for a callout defer, a "defer" | |
3394 | verb, and for a header verify when smtp_return_error_details is set. | |
3395 | ||
3396 | This conditional logic is all somewhat of a mess because of the odd | |
3397 | interactions between temp_details and return_error_details. One day it should | |
3398 | be re-implemented in a tidier fashion. */ | |
3399 | ||
3400 | else | |
2ea97746 | 3401 | if (f.acl_temp_details && user_msg) |
420a0d19 | 3402 | { |
2ea97746 CE |
3403 | if ( smtp_return_error_details |
3404 | && sender_verified_failed | |
3405 | && sender_verified_failed->message | |
3406 | ) | |
420a0d19 | 3407 | smtp_respond(smtp_code, codelen, FALSE, sender_verified_failed->message); |
2ea97746 | 3408 | |
420a0d19 CE |
3409 | smtp_respond(smtp_code, codelen, TRUE, user_msg); |
3410 | } | |
3411 | else | |
3412 | smtp_respond(smtp_code, codelen, TRUE, | |
3413 | US"Temporary local problem - please try later"); | |
420a0d19 CE |
3414 | |
3415 | /* Log the incident to the logs that are specified by log_reject_target | |
3416 | (default main, reject). This can be empty to suppress logging of rejections. If | |
3417 | the connection is not forcibly to be dropped, return 0. Otherwise, log why it | |
3418 | is closing if required and return 2. */ | |
3419 | ||
3420 | if (log_reject_target != 0) | |
3421 | { | |
3422 | #ifdef SUPPORT_TLS | |
2ea97746 CE |
3423 | gstring * g = s_tlslog(NULL); |
3424 | uschar * tls = string_from_gstring(g); | |
3425 | if (!tls) tls = US""; | |
420a0d19 | 3426 | #else |
2ea97746 | 3427 | uschar * tls = US""; |
420a0d19 | 3428 | #endif |
2ea97746 CE |
3429 | log_write(where == ACL_WHERE_CONNECT ? L_connection_reject : 0, |
3430 | log_reject_target, "%s%s%s %s%srejected %s%s", | |
3431 | LOGGING(dnssec) && sender_host_dnssec ? US" DS" : US"", | |
3432 | host_and_ident(TRUE), | |
3433 | tls, | |
3434 | sender_info, | |
3435 | rc == FAIL ? US"" : US"temporarily ", | |
3436 | what, log_msg); | |
420a0d19 CE |
3437 | } |
3438 | ||
3439 | if (!drop) return 0; | |
3440 | ||
3441 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by DROP in ACL", | |
3442 | smtp_get_connection_info()); | |
3443 | ||
3444 | /* Run the not-quit ACL, but without any custom messages. This should not be a | |
3445 | problem, because we get here only if some other ACL has issued "drop", and | |
3446 | in that case, *its* custom messages will have been used above. */ | |
3447 | ||
3448 | smtp_notquit_exit(US"acl-drop", NULL, NULL); | |
3449 | return 2; | |
3450 | } | |
3451 | ||
3452 | ||
3453 | ||
3454 | ||
3455 | /************************************************* | |
3456 | * Handle SMTP exit when QUIT is not given * | |
3457 | *************************************************/ | |
3458 | ||
3459 | /* This function provides a logging/statistics hook for when an SMTP connection | |
3460 | is dropped on the floor or the other end goes away. It's a global function | |
3461 | because it's called from receive.c as well as this module. As well as running | |
3462 | the NOTQUIT ACL, if there is one, this function also outputs a final SMTP | |
3463 | response, either with a custom message from the ACL, or using a default. There | |
3464 | is one case, however, when no message is output - after "drop". In that case, | |
3465 | the ACL that obeyed "drop" has already supplied the custom message, and NULL is | |
3466 | passed to this function. | |
3467 | ||
3468 | In case things go wrong while processing this function, causing an error that | |
2ea97746 | 3469 | may re-enter this function, there is a recursion check. |
420a0d19 CE |
3470 | |
3471 | Arguments: | |
3472 | reason What $smtp_notquit_reason will be set to in the ACL; | |
3473 | if NULL, the ACL is not run | |
3474 | code The error code to return as part of the response | |
3475 | defaultrespond The default message if there's no user_msg | |
3476 | ||
3477 | Returns: Nothing | |
3478 | */ | |
3479 | ||
3480 | void | |
3481 | smtp_notquit_exit(uschar *reason, uschar *code, uschar *defaultrespond, ...) | |
3482 | { | |
3483 | int rc; | |
3484 | uschar *user_msg = NULL; | |
3485 | uschar *log_msg = NULL; | |
3486 | ||
2ea97746 | 3487 | /* Check for recursive call */ |
420a0d19 | 3488 | |
2ea97746 | 3489 | if (fl.smtp_exit_function_called) |
420a0d19 CE |
3490 | { |
3491 | log_write(0, LOG_PANIC, "smtp_notquit_exit() called more than once (%s)", | |
3492 | reason); | |
3493 | return; | |
3494 | } | |
2ea97746 | 3495 | fl.smtp_exit_function_called = TRUE; |
420a0d19 CE |
3496 | |
3497 | /* Call the not-QUIT ACL, if there is one, unless no reason is given. */ | |
3498 | ||
2ea97746 | 3499 | if (acl_smtp_notquit && reason) |
420a0d19 CE |
3500 | { |
3501 | smtp_notquit_reason = reason; | |
2ea97746 CE |
3502 | if ((rc = acl_check(ACL_WHERE_NOTQUIT, NULL, acl_smtp_notquit, &user_msg, |
3503 | &log_msg)) == ERROR) | |
420a0d19 CE |
3504 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for not-QUIT returned ERROR: %s", |
3505 | log_msg); | |
3506 | } | |
3507 | ||
2ea97746 CE |
3508 | /* If the connection was dropped, we certainly are no longer talking TLS */ |
3509 | tls_in.active.sock = -1; | |
3510 | ||
420a0d19 | 3511 | /* Write an SMTP response if we are expected to give one. As the default |
2ea97746 | 3512 | responses are all internal, they should be reasonable size. */ |
420a0d19 | 3513 | |
2ea97746 | 3514 | if (code && defaultrespond) |
420a0d19 | 3515 | { |
2ea97746 CE |
3516 | if (user_msg) |
3517 | smtp_respond(code, 3, TRUE, user_msg); | |
3518 | else | |
420a0d19 | 3519 | { |
2ea97746 | 3520 | gstring * g; |
420a0d19 | 3521 | va_list ap; |
2ea97746 | 3522 | |
420a0d19 | 3523 | va_start(ap, defaultrespond); |
2ea97746 | 3524 | g = string_vformat(NULL, TRUE, CS defaultrespond, ap); |
420a0d19 | 3525 | va_end(ap); |
2ea97746 | 3526 | smtp_printf("%s %s\r\n", FALSE, code, string_from_gstring(g)); |
420a0d19 | 3527 | } |
420a0d19 CE |
3528 | mac_smtp_fflush(); |
3529 | } | |
3530 | } | |
3531 | ||
3532 | ||
3533 | ||
3534 | ||
3535 | /************************************************* | |
3536 | * Verify HELO argument * | |
3537 | *************************************************/ | |
3538 | ||
3539 | /* This function is called if helo_verify_hosts or helo_try_verify_hosts is | |
3540 | matched. It is also called from ACL processing if verify = helo is used and | |
3541 | verification was not previously tried (i.e. helo_try_verify_hosts was not | |
3542 | matched). The result of its processing is to set helo_verified and | |
3543 | helo_verify_failed. These variables should both be FALSE for this function to | |
3544 | be called. | |
3545 | ||
3546 | Note that EHLO/HELO is legitimately allowed to quote an address literal. Allow | |
3547 | for IPv6 ::ffff: literals. | |
3548 | ||
3549 | Argument: none | |
3550 | Returns: TRUE if testing was completed; | |
3551 | FALSE on a temporary failure | |
3552 | */ | |
3553 | ||
3554 | BOOL | |
3555 | smtp_verify_helo(void) | |
3556 | { | |
3557 | BOOL yield = TRUE; | |
3558 | ||
3559 | HDEBUG(D_receive) debug_printf("verifying EHLO/HELO argument \"%s\"\n", | |
3560 | sender_helo_name); | |
3561 | ||
3562 | if (sender_helo_name == NULL) | |
3563 | { | |
3564 | HDEBUG(D_receive) debug_printf("no EHLO/HELO command was issued\n"); | |
3565 | } | |
3566 | ||
3567 | /* Deal with the case of -bs without an IP address */ | |
3568 | ||
3569 | else if (sender_host_address == NULL) | |
3570 | { | |
3571 | HDEBUG(D_receive) debug_printf("no client IP address: assume success\n"); | |
2ea97746 | 3572 | f.helo_verified = TRUE; |
420a0d19 CE |
3573 | } |
3574 | ||
3575 | /* Deal with the more common case when there is a sending IP address */ | |
3576 | ||
3577 | else if (sender_helo_name[0] == '[') | |
3578 | { | |
2ea97746 | 3579 | f.helo_verified = Ustrncmp(sender_helo_name+1, sender_host_address, |
420a0d19 CE |
3580 | Ustrlen(sender_host_address)) == 0; |
3581 | ||
2ea97746 CE |
3582 | #if HAVE_IPV6 |
3583 | if (!f.helo_verified) | |
420a0d19 CE |
3584 | { |
3585 | if (strncmpic(sender_host_address, US"::ffff:", 7) == 0) | |
2ea97746 | 3586 | f.helo_verified = Ustrncmp(sender_helo_name + 1, |
420a0d19 CE |
3587 | sender_host_address + 7, Ustrlen(sender_host_address) - 7) == 0; |
3588 | } | |
2ea97746 | 3589 | #endif |
420a0d19 CE |
3590 | |
3591 | HDEBUG(D_receive) | |
2ea97746 | 3592 | { if (f.helo_verified) debug_printf("matched host address\n"); } |
420a0d19 CE |
3593 | } |
3594 | ||
3595 | /* Do a reverse lookup if one hasn't already given a positive or negative | |
3596 | response. If that fails, or the name doesn't match, try checking with a forward | |
3597 | lookup. */ | |
3598 | ||
3599 | else | |
3600 | { | |
3601 | if (sender_host_name == NULL && !host_lookup_failed) | |
3602 | yield = host_name_lookup() != DEFER; | |
3603 | ||
3604 | /* If a host name is known, check it and all its aliases. */ | |
3605 | ||
2ea97746 CE |
3606 | if (sender_host_name) |
3607 | if ((f.helo_verified = strcmpic(sender_host_name, sender_helo_name) == 0)) | |
420a0d19 | 3608 | { |
2ea97746 | 3609 | sender_helo_dnssec = sender_host_dnssec; |
420a0d19 CE |
3610 | HDEBUG(D_receive) debug_printf("matched host name\n"); |
3611 | } | |
3612 | else | |
3613 | { | |
3614 | uschar **aliases = sender_host_aliases; | |
2ea97746 CE |
3615 | while (*aliases) |
3616 | if ((f.helo_verified = strcmpic(*aliases++, sender_helo_name) == 0)) | |
3617 | { | |
3618 | sender_helo_dnssec = sender_host_dnssec; | |
3619 | break; | |
3620 | } | |
3621 | ||
3622 | HDEBUG(D_receive) if (f.helo_verified) | |
420a0d19 | 3623 | debug_printf("matched alias %s\n", *(--aliases)); |
420a0d19 | 3624 | } |
420a0d19 CE |
3625 | |
3626 | /* Final attempt: try a forward lookup of the helo name */ | |
3627 | ||
2ea97746 | 3628 | if (!f.helo_verified) |
420a0d19 CE |
3629 | { |
3630 | int rc; | |
3631 | host_item h; | |
2ea97746 CE |
3632 | dnssec_domains d; |
3633 | host_item *hh; | |
3634 | ||
420a0d19 CE |
3635 | h.name = sender_helo_name; |
3636 | h.address = NULL; | |
3637 | h.mx = MX_NONE; | |
3638 | h.next = NULL; | |
2ea97746 CE |
3639 | d.request = US"*"; |
3640 | d.require = US""; | |
3641 | ||
420a0d19 CE |
3642 | HDEBUG(D_receive) debug_printf("getting IP address for %s\n", |
3643 | sender_helo_name); | |
2ea97746 CE |
3644 | rc = host_find_bydns(&h, NULL, HOST_FIND_BY_A | HOST_FIND_BY_AAAA, |
3645 | NULL, NULL, NULL, &d, NULL, NULL); | |
420a0d19 | 3646 | if (rc == HOST_FOUND || rc == HOST_FOUND_LOCAL) |
2ea97746 | 3647 | for (hh = &h; hh; hh = hh->next) |
420a0d19 CE |
3648 | if (Ustrcmp(hh->address, sender_host_address) == 0) |
3649 | { | |
2ea97746 CE |
3650 | f.helo_verified = TRUE; |
3651 | if (h.dnssec == DS_YES) sender_helo_dnssec = TRUE; | |
420a0d19 | 3652 | HDEBUG(D_receive) |
2ea97746 CE |
3653 | { |
3654 | debug_printf("IP address for %s matches calling address\n" | |
3655 | "Forward DNS security status: %sverified\n", | |
3656 | sender_helo_name, sender_helo_dnssec ? "" : "un"); | |
3657 | } | |
420a0d19 CE |
3658 | break; |
3659 | } | |
420a0d19 CE |
3660 | } |
3661 | } | |
3662 | ||
2ea97746 | 3663 | if (!f.helo_verified) f.helo_verify_failed = TRUE; /* We've tried ... */ |
420a0d19 CE |
3664 | return yield; |
3665 | } | |
3666 | ||
3667 | ||
3668 | ||
3669 | ||
3670 | /************************************************* | |
3671 | * Send user response message * | |
3672 | *************************************************/ | |
3673 | ||
3674 | /* This function is passed a default response code and a user message. It calls | |
3675 | smtp_message_code() to check and possibly modify the response code, and then | |
3676 | calls smtp_respond() to transmit the response. I put this into a function | |
3677 | just to avoid a lot of repetition. | |
3678 | ||
3679 | Arguments: | |
3680 | code the response code | |
3681 | user_msg the user message | |
3682 | ||
3683 | Returns: nothing | |
3684 | */ | |
3685 | ||
3686 | static void | |
3687 | smtp_user_msg(uschar *code, uschar *user_msg) | |
3688 | { | |
3689 | int len = 3; | |
2ea97746 | 3690 | smtp_message_code(&code, &len, &user_msg, NULL, TRUE); |
420a0d19 CE |
3691 | smtp_respond(code, len, TRUE, user_msg); |
3692 | } | |
3693 | ||
3694 | ||
3695 | ||
2ea97746 CE |
3696 | static int |
3697 | smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss) | |
3698 | { | |
3699 | const uschar *set_id = NULL; | |
3700 | int rc, i; | |
3701 | ||
3702 | /* Run the checking code, passing the remainder of the command line as | |
3703 | data. Initials the $auth<n> variables as empty. Initialize $0 empty and set | |
3704 | it as the only set numerical variable. The authenticator may set $auth<n> | |
3705 | and also set other numeric variables. The $auth<n> variables are preferred | |
3706 | nowadays; the numerical variables remain for backwards compatibility. | |
3707 | ||
3708 | Afterwards, have a go at expanding the set_id string, even if | |
3709 | authentication failed - for bad passwords it can be useful to log the | |
3710 | userid. On success, require set_id to expand and exist, and put it in | |
3711 | authenticated_id. Save this in permanent store, as the working store gets | |
3712 | reset at HELO, RSET, etc. */ | |
3713 | ||
3714 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; | |
3715 | expand_nmax = 0; | |
3716 | expand_nlength[0] = 0; /* $0 contains nothing */ | |
3717 | ||
3718 | rc = (au->info->servercode)(au, smtp_cmd_data); | |
3719 | if (au->set_id) set_id = expand_string(au->set_id); | |
3720 | expand_nmax = -1; /* Reset numeric variables */ | |
3721 | for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */ | |
3722 | ||
3723 | /* The value of authenticated_id is stored in the spool file and printed in | |
3724 | log lines. It must not contain binary zeros or newline characters. In | |
3725 | normal use, it never will, but when playing around or testing, this error | |
3726 | can (did) happen. To guard against this, ensure that the id contains only | |
3727 | printing characters. */ | |
3728 | ||
3729 | if (set_id) set_id = string_printing(set_id); | |
3730 | ||
3731 | /* For the non-OK cases, set up additional logging data if set_id | |
3732 | is not empty. */ | |
3733 | ||
3734 | if (rc != OK) | |
3735 | set_id = set_id && *set_id | |
3736 | ? string_sprintf(" (set_id=%s)", set_id) : US""; | |
3737 | ||
3738 | /* Switch on the result */ | |
3739 | ||
3740 | switch(rc) | |
3741 | { | |
3742 | case OK: | |
3743 | if (!au->set_id || set_id) /* Complete success */ | |
3744 | { | |
3745 | if (set_id) authenticated_id = string_copy_malloc(set_id); | |
3746 | sender_host_authenticated = au->name; | |
3747 | sender_host_auth_pubname = au->public_name; | |
3748 | authentication_failed = FALSE; | |
3749 | authenticated_fail_id = NULL; /* Impossible to already be set? */ | |
3750 | ||
3751 | received_protocol = | |
3752 | (sender_host_address ? protocols : protocols_local) | |
3753 | [pextend + pauthed + (tls_in.active.sock >= 0 ? pcrpted:0)]; | |
3754 | *s = *ss = US"235 Authentication succeeded"; | |
3755 | authenticated_by = au; | |
3756 | break; | |
3757 | } | |
3758 | ||
3759 | /* Authentication succeeded, but we failed to expand the set_id string. | |
3760 | Treat this as a temporary error. */ | |
3761 | ||
3762 | auth_defer_msg = expand_string_message; | |
3763 | /* Fall through */ | |
3764 | ||
3765 | case DEFER: | |
3766 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3767 | *s = string_sprintf("435 Unable to authenticate at present%s", | |
3768 | auth_defer_user_msg); | |
3769 | *ss = string_sprintf("435 Unable to authenticate at present%s: %s", | |
3770 | set_id, auth_defer_msg); | |
3771 | break; | |
3772 | ||
3773 | case BAD64: | |
3774 | *s = *ss = US"501 Invalid base64 data"; | |
3775 | break; | |
3776 | ||
3777 | case CANCELLED: | |
3778 | *s = *ss = US"501 Authentication cancelled"; | |
3779 | break; | |
3780 | ||
3781 | case UNEXPECTED: | |
3782 | *s = *ss = US"553 Initial data not expected"; | |
3783 | break; | |
3784 | ||
3785 | case FAIL: | |
3786 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3787 | *s = US"535 Incorrect authentication data"; | |
3788 | *ss = string_sprintf("535 Incorrect authentication data%s", set_id); | |
3789 | break; | |
3790 | ||
3791 | default: | |
3792 | if (set_id) authenticated_fail_id = string_copy_malloc(set_id); | |
3793 | *s = US"435 Internal error"; | |
3794 | *ss = string_sprintf("435 Internal error%s: return %d from authentication " | |
3795 | "check", set_id, rc); | |
3796 | break; | |
3797 | } | |
3798 | ||
3799 | return rc; | |
3800 | } | |
3801 | ||
3802 | ||
3803 | ||
3804 | ||
3805 | ||
3806 | static int | |
3807 | qualify_recipient(uschar ** recipient, uschar * smtp_cmd_data, uschar * tag) | |
3808 | { | |
3809 | int rd; | |
3810 | if (f.allow_unqualified_recipient || strcmpic(*recipient, US"postmaster") == 0) | |
3811 | { | |
3812 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
3813 | *recipient); | |
3814 | rd = Ustrlen(recipient) + 1; | |
3815 | *recipient = rewrite_address_qualify(*recipient, TRUE); | |
3816 | return rd; | |
3817 | } | |
3818 | smtp_printf("501 %s: recipient address must contain a domain\r\n", FALSE, | |
3819 | smtp_cmd_data); | |
3820 | log_write(L_smtp_syntax_error, | |
3821 | LOG_MAIN|LOG_REJECT, "unqualified %s rejected: <%s> %s%s", | |
3822 | tag, *recipient, host_and_ident(TRUE), host_lookup_msg); | |
3823 | return 0; | |
3824 | } | |
3825 | ||
3826 | ||
3827 | ||
3828 | ||
3829 | static void | |
3830 | smtp_quit_handler(uschar ** user_msgp, uschar ** log_msgp) | |
3831 | { | |
3832 | HAD(SCH_QUIT); | |
3833 | incomplete_transaction_log(US"QUIT"); | |
3834 | if (acl_smtp_quit) | |
3835 | { | |
3836 | int rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, user_msgp, log_msgp); | |
3837 | if (rc == ERROR) | |
3838 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
3839 | *log_msgp); | |
3840 | } | |
3841 | if (*user_msgp) | |
3842 | smtp_respond(US"221", 3, TRUE, *user_msgp); | |
3843 | else | |
3844 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); | |
3845 | ||
3846 | #ifdef SUPPORT_TLS | |
3847 | tls_close(NULL, TLS_SHUTDOWN_NOWAIT); | |
3848 | #endif | |
3849 | ||
3850 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", | |
3851 | smtp_get_connection_info()); | |
3852 | } | |
3853 | ||
3854 | ||
3855 | static void | |
3856 | smtp_rset_handler(void) | |
3857 | { | |
3858 | HAD(SCH_RSET); | |
3859 | incomplete_transaction_log(US"RSET"); | |
3860 | smtp_printf("250 Reset OK\r\n", FALSE); | |
3861 | cmd_list[CMD_LIST_RSET].is_mail_cmd = FALSE; | |
3862 | } | |
3863 | ||
3864 | ||
3865 | ||
420a0d19 CE |
3866 | /************************************************* |
3867 | * Initialize for SMTP incoming message * | |
3868 | *************************************************/ | |
3869 | ||
3870 | /* This function conducts the initial dialogue at the start of an incoming SMTP | |
3871 | message, and builds a list of recipients. However, if the incoming message | |
3872 | is part of a batch (-bS option) a separate function is called since it would | |
3873 | be messy having tests splattered about all over this function. This function | |
3874 | therefore handles the case where interaction is occurring. The input and output | |
3875 | files are set up in smtp_in and smtp_out. | |
3876 | ||
3877 | The global recipients_list is set to point to a vector of recipient_item | |
3878 | blocks, whose number is given by recipients_count. This is extended by the | |
3879 | receive_add_recipient() function. The global variable sender_address is set to | |
3880 | the sender's address. The yield is +1 if a message has been successfully | |
3881 | started, 0 if a QUIT command was encountered or the connection was refused from | |
3882 | the particular host, or -1 if the connection was lost. | |
3883 | ||
3884 | Argument: none | |
3885 | ||
3886 | Returns: > 0 message successfully started (reached DATA) | |
3887 | = 0 QUIT read or end of file reached or call refused | |
3888 | < 0 lost connection | |
3889 | */ | |
3890 | ||
3891 | int | |
3892 | smtp_setup_msg(void) | |
3893 | { | |
3894 | int done = 0; | |
3895 | BOOL toomany = FALSE; | |
3896 | BOOL discarded = FALSE; | |
3897 | BOOL last_was_rej_mail = FALSE; | |
3898 | BOOL last_was_rcpt = FALSE; | |
3899 | void *reset_point = store_get(0); | |
3900 | ||
3901 | DEBUG(D_receive) debug_printf("smtp_setup_msg entered\n"); | |
3902 | ||
3903 | /* Reset for start of new message. We allow one RSET not to be counted as a | |
3904 | nonmail command, for those MTAs that insist on sending it between every | |
3905 | message. Ditto for EHLO/HELO and for STARTTLS, to allow for going in and out of | |
3906 | TLS between messages (an Exim client may do this if it has messages queued up | |
3907 | for the host). Note: we do NOT reset AUTH at this point. */ | |
3908 | ||
3909 | smtp_reset(reset_point); | |
3910 | message_ended = END_NOTSTARTED; | |
3911 | ||
2ea97746 CE |
3912 | chunking_state = f.chunking_offered ? CHUNKING_OFFERED : CHUNKING_NOT_OFFERED; |
3913 | ||
420a0d19 CE |
3914 | cmd_list[CMD_LIST_RSET].is_mail_cmd = TRUE; |
3915 | cmd_list[CMD_LIST_HELO].is_mail_cmd = TRUE; | |
3916 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
3917 | #ifdef SUPPORT_TLS | |
3918 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE; | |
3919 | #endif | |
3920 | ||
3921 | /* Set the local signal handler for SIGTERM - it tries to end off tidily */ | |
3922 | ||
2ea97746 | 3923 | had_command_sigterm = 0; |
420a0d19 CE |
3924 | os_non_restarting_signal(SIGTERM, command_sigterm_handler); |
3925 | ||
3926 | /* Batched SMTP is handled in a different function. */ | |
3927 | ||
3928 | if (smtp_batched_input) return smtp_setup_batch_msg(); | |
3929 | ||
3930 | /* Deal with SMTP commands. This loop is exited by setting done to a POSITIVE | |
3931 | value. The values are 2 larger than the required yield of the function. */ | |
3932 | ||
3933 | while (done <= 0) | |
3934 | { | |
2ea97746 | 3935 | const uschar **argv; |
420a0d19 CE |
3936 | uschar *etrn_command; |
3937 | uschar *etrn_serialize_key; | |
3938 | uschar *errmess; | |
3939 | uschar *log_msg, *smtp_code; | |
3940 | uschar *user_msg = NULL; | |
3941 | uschar *recipient = NULL; | |
3942 | uschar *hello = NULL; | |
420a0d19 CE |
3943 | uschar *s, *ss; |
3944 | BOOL was_rej_mail = FALSE; | |
3945 | BOOL was_rcpt = FALSE; | |
3946 | void (*oldsignal)(int); | |
3947 | pid_t pid; | |
3948 | int start, end, sender_domain, recipient_domain; | |
2ea97746 CE |
3949 | int rc; |
3950 | int c; | |
420a0d19 | 3951 | auth_instance *au; |
420a0d19 | 3952 | uschar *orcpt = NULL; |
2ea97746 CE |
3953 | int dsn_flags; |
3954 | gstring * g; | |
3955 | ||
3956 | #ifdef AUTH_TLS | |
3957 | /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */ | |
3958 | if ( tls_in.active.sock >= 0 | |
3959 | && tls_in.peercert | |
3960 | && tls_in.certificate_verified | |
3961 | && cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd | |
3962 | ) | |
3963 | { | |
3964 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = FALSE; | |
3965 | ||
3966 | for (au = auths; au; au = au->next) | |
3967 | if (strcmpic(US"tls", au->driver_name) == 0) | |
3968 | { | |
3969 | if ( acl_smtp_auth | |
3970 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
3971 | &user_msg, &log_msg)) != OK | |
3972 | ) | |
3973 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); | |
3974 | else | |
3975 | { | |
3976 | smtp_cmd_data = NULL; | |
3977 | ||
3978 | if (smtp_in_auth(au, &s, &ss) == OK) | |
3979 | { DEBUG(D_auth) debug_printf("tls auth succeeded\n"); } | |
3980 | else | |
3981 | { DEBUG(D_auth) debug_printf("tls auth not succeeded\n"); } | |
3982 | } | |
3983 | break; | |
3984 | } | |
3985 | } | |
3986 | #endif | |
3987 | ||
3988 | #ifdef TCP_QUICKACK | |
3989 | if (smtp_in) /* Avoid pure-ACKs while in cmd pingpong phase */ | |
3990 | (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK, | |
3991 | US &off, sizeof(off)); | |
420a0d19 CE |
3992 | #endif |
3993 | ||
2ea97746 CE |
3994 | switch(smtp_read_command( |
3995 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
3996 | !fl.pipe_connect_acceptable, | |
3997 | #else | |
3998 | TRUE, | |
3999 | #endif | |
4000 | GETC_BUFFER_UNLIMITED)) | |
420a0d19 CE |
4001 | { |
4002 | /* The AUTH command is not permitted to occur inside a transaction, and may | |
4003 | occur successfully only once per connection. Actually, that isn't quite | |
4004 | true. When TLS is started, all previous information about a connection must | |
4005 | be discarded, so a new AUTH is permitted at that time. | |
4006 | ||
4007 | AUTH may only be used when it has been advertised. However, it seems that | |
4008 | there are clients that send AUTH when it hasn't been advertised, some of | |
4009 | them even doing this after HELO. And there are MTAs that accept this. Sigh. | |
4010 | So there's a get-out that allows this to happen. | |
4011 | ||
4012 | AUTH is initially labelled as a "nonmail command" so that one occurrence | |
4013 | doesn't get counted. We change the label here so that multiple failing | |
4014 | AUTHS will eventually hit the nonmail threshold. */ | |
4015 | ||
4016 | case AUTH_CMD: | |
2ea97746 CE |
4017 | HAD(SCH_AUTH); |
4018 | authentication_failed = TRUE; | |
4019 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = FALSE; | |
4020 | ||
4021 | if (!fl.auth_advertised && !f.allow_auth_unadvertised) | |
4022 | { | |
4023 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4024 | US"AUTH command used when not advertised"); | |
4025 | break; | |
4026 | } | |
4027 | if (sender_host_authenticated) | |
4028 | { | |
4029 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4030 | US"already authenticated"); | |
4031 | break; | |
4032 | } | |
4033 | if (sender_address) | |
4034 | { | |
4035 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4036 | US"not permitted in mail transaction"); | |
4037 | break; | |
4038 | } | |
420a0d19 | 4039 | |
2ea97746 | 4040 | /* Check the ACL */ |
420a0d19 | 4041 | |
2ea97746 CE |
4042 | if ( acl_smtp_auth |
4043 | && (rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, | |
4044 | &user_msg, &log_msg)) != OK | |
4045 | ) | |
4046 | { | |
4047 | done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg); | |
4048 | break; | |
4049 | } | |
420a0d19 | 4050 | |
2ea97746 CE |
4051 | /* Find the name of the requested authentication mechanism. */ |
4052 | ||
4053 | s = smtp_cmd_data; | |
4054 | while ((c = *smtp_cmd_data) != 0 && !isspace(c)) | |
4055 | { | |
4056 | if (!isalnum(c) && c != '-' && c != '_') | |
4057 | { | |
4058 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4059 | US"invalid character in authentication mechanism name"); | |
4060 | goto COMMAND_LOOP; | |
4061 | } | |
4062 | smtp_cmd_data++; | |
4063 | } | |
420a0d19 | 4064 | |
2ea97746 CE |
4065 | /* If not at the end of the line, we must be at white space. Terminate the |
4066 | name and move the pointer on to any data that may be present. */ | |
420a0d19 | 4067 | |
2ea97746 CE |
4068 | if (*smtp_cmd_data != 0) |
4069 | { | |
4070 | *smtp_cmd_data++ = 0; | |
4071 | while (isspace(*smtp_cmd_data)) smtp_cmd_data++; | |
4072 | } | |
420a0d19 | 4073 | |
2ea97746 CE |
4074 | /* Search for an authentication mechanism which is configured for use |
4075 | as a server and which has been advertised (unless, sigh, allow_auth_ | |
4076 | unadvertised is set). */ | |
420a0d19 | 4077 | |
2ea97746 CE |
4078 | for (au = auths; au; au = au->next) |
4079 | if (strcmpic(s, au->public_name) == 0 && au->server && | |
4080 | (au->advertised || f.allow_auth_unadvertised)) | |
4081 | break; | |
420a0d19 | 4082 | |
2ea97746 CE |
4083 | if (au) |
4084 | { | |
4085 | c = smtp_in_auth(au, &s, &ss); | |
420a0d19 | 4086 | |
2ea97746 CE |
4087 | smtp_printf("%s\r\n", FALSE, s); |
4088 | if (c != OK) | |
4089 | log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s", | |
4090 | au->name, host_and_ident(FALSE), ss); | |
4091 | } | |
4092 | else | |
4093 | done = synprot_error(L_smtp_protocol_error, 504, NULL, | |
4094 | string_sprintf("%s authentication mechanism not supported", s)); | |
420a0d19 | 4095 | |
2ea97746 | 4096 | break; /* AUTH_CMD */ |
420a0d19 | 4097 | |
2ea97746 CE |
4098 | /* The HELO/EHLO commands are permitted to appear in the middle of a |
4099 | session as well as at the beginning. They have the effect of a reset in | |
4100 | addition to their other functions. Their absence at the start cannot be | |
4101 | taken to be an error. | |
420a0d19 | 4102 | |
2ea97746 | 4103 | RFC 2821 says: |
420a0d19 | 4104 | |
2ea97746 CE |
4105 | If the EHLO command is not acceptable to the SMTP server, 501, 500, |
4106 | or 502 failure replies MUST be returned as appropriate. The SMTP | |
4107 | server MUST stay in the same state after transmitting these replies | |
4108 | that it was in before the EHLO was received. | |
420a0d19 CE |
4109 | |
4110 | Therefore, we do not do the reset until after checking the command for | |
4111 | acceptability. This change was made for Exim release 4.11. Previously | |
4112 | it did the reset first. */ | |
4113 | ||
4114 | case HELO_CMD: | |
2ea97746 CE |
4115 | HAD(SCH_HELO); |
4116 | hello = US"HELO"; | |
4117 | fl.esmtp = FALSE; | |
4118 | goto HELO_EHLO; | |
420a0d19 CE |
4119 | |
4120 | case EHLO_CMD: | |
2ea97746 CE |
4121 | HAD(SCH_EHLO); |
4122 | hello = US"EHLO"; | |
4123 | fl.esmtp = TRUE; | |
420a0d19 CE |
4124 | |
4125 | HELO_EHLO: /* Common code for HELO and EHLO */ | |
2ea97746 CE |
4126 | cmd_list[CMD_LIST_HELO].is_mail_cmd = FALSE; |
4127 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = FALSE; | |
4128 | ||
4129 | /* Reject the HELO if its argument was invalid or non-existent. A | |
4130 | successful check causes the argument to be saved in malloc store. */ | |
4131 | ||
4132 | if (!check_helo(smtp_cmd_data)) | |
4133 | { | |
4134 | smtp_printf("501 Syntactically invalid %s argument(s)\r\n", FALSE, hello); | |
4135 | ||
4136 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected %s from %s: syntactically " | |
4137 | "invalid argument(s): %s", hello, host_and_ident(FALSE), | |
4138 | *smtp_cmd_argument == 0 ? US"(no argument given)" : | |
4139 | string_printing(smtp_cmd_argument)); | |
4140 | ||
4141 | if (++synprot_error_count > smtp_max_synprot_errors) | |
4142 | { | |
4143 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
4144 | "syntax or protocol errors (last command was \"%s\")", | |
4145 | host_and_ident(FALSE), string_printing(smtp_cmd_buffer)); | |
4146 | done = 1; | |
4147 | } | |
4148 | ||
4149 | break; | |
4150 | } | |
420a0d19 | 4151 | |
2ea97746 CE |
4152 | /* If sender_host_unknown is true, we have got here via the -bs interface, |
4153 | not called from inetd. Otherwise, we are running an IP connection and the | |
4154 | host address will be set. If the helo name is the primary name of this | |
4155 | host and we haven't done a reverse lookup, force one now. If helo_required | |
4156 | is set, ensure that the HELO name matches the actual host. If helo_verify | |
4157 | is set, do the same check, but softly. */ | |
4158 | ||
4159 | if (!f.sender_host_unknown) | |
4160 | { | |
4161 | BOOL old_helo_verified = f.helo_verified; | |
4162 | uschar *p = smtp_cmd_data; | |
4163 | ||
4164 | while (*p != 0 && !isspace(*p)) { *p = tolower(*p); p++; } | |
4165 | *p = 0; | |
4166 | ||
4167 | /* Force a reverse lookup if HELO quoted something in helo_lookup_domains | |
4168 | because otherwise the log can be confusing. */ | |
4169 | ||
4170 | if ( !sender_host_name | |
4171 | && match_isinlist(sender_helo_name, CUSS &helo_lookup_domains, 0, | |
4172 | &domainlist_anchor, NULL, MCL_DOMAIN, TRUE, NULL) == OK) | |
4173 | (void)host_name_lookup(); | |
4174 | ||
4175 | /* Rebuild the fullhost info to include the HELO name (and the real name | |
4176 | if it was looked up.) */ | |
4177 | ||
4178 | host_build_sender_fullhost(); /* Rebuild */ | |
4179 | set_process_info("handling%s incoming connection from %s", | |
4180 | tls_in.active.sock >= 0 ? " TLS" : "", host_and_ident(FALSE)); | |
4181 | ||
4182 | /* Verify if configured. This doesn't give much security, but it does | |
4183 | make some people happy to be able to do it. If helo_required is set, | |
4184 | (host matches helo_verify_hosts) failure forces rejection. If helo_verify | |
4185 | is set (host matches helo_try_verify_hosts), it does not. This is perhaps | |
4186 | now obsolescent, since the verification can now be requested selectively | |
4187 | at ACL time. */ | |
4188 | ||
4189 | f.helo_verified = f.helo_verify_failed = sender_helo_dnssec = FALSE; | |
4190 | if (fl.helo_required || fl.helo_verify) | |
4191 | { | |
4192 | BOOL tempfail = !smtp_verify_helo(); | |
4193 | if (!f.helo_verified) | |
4194 | { | |
4195 | if (fl.helo_required) | |
4196 | { | |
4197 | smtp_printf("%d %s argument does not match calling host\r\n", FALSE, | |
4198 | tempfail? 451 : 550, hello); | |
4199 | log_write(0, LOG_MAIN|LOG_REJECT, "%srejected \"%s %s\" from %s", | |
4200 | tempfail? "temporarily " : "", | |
4201 | hello, sender_helo_name, host_and_ident(FALSE)); | |
4202 | f.helo_verified = old_helo_verified; | |
4203 | break; /* End of HELO/EHLO processing */ | |
4204 | } | |
4205 | HDEBUG(D_all) debug_printf("%s verification failed but host is in " | |
4206 | "helo_try_verify_hosts\n", hello); | |
4207 | } | |
4208 | } | |
4209 | } | |
420a0d19 | 4210 | |
2ea97746 CE |
4211 | #ifdef SUPPORT_SPF |
4212 | /* set up SPF context */ | |
4213 | spf_init(sender_helo_name, sender_host_address); | |
420a0d19 CE |
4214 | #endif |
4215 | ||
2ea97746 CE |
4216 | /* Apply an ACL check if one is defined; afterwards, recheck |
4217 | synchronization in case the client started sending in a delay. */ | |
4218 | ||
4219 | if (acl_smtp_helo) | |
4220 | if ((rc = acl_check(ACL_WHERE_HELO, NULL, acl_smtp_helo, | |
4221 | &user_msg, &log_msg)) != OK) | |
4222 | { | |
4223 | done = smtp_handle_acl_fail(ACL_WHERE_HELO, rc, user_msg, log_msg); | |
4224 | if (sender_helo_name) | |
4225 | { | |
4226 | store_free(sender_helo_name); | |
4227 | sender_helo_name = NULL; | |
4228 | } | |
4229 | host_build_sender_fullhost(); /* Rebuild */ | |
4230 | break; | |
4231 | } | |
4232 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
4233 | else if (!fl.pipe_connect_acceptable && !check_sync()) | |
4234 | #else | |
4235 | else if (!check_sync()) | |
4236 | #endif | |
4237 | goto SYNC_FAILURE; | |
420a0d19 | 4238 | |
2ea97746 CE |
4239 | /* Generate an OK reply. The default string includes the ident if present, |
4240 | and also the IP address if present. Reflecting back the ident is intended | |
4241 | as a deterrent to mail forgers. For maximum efficiency, and also because | |
4242 | some broken systems expect each response to be in a single packet, arrange | |
4243 | that the entire reply is sent in one write(). */ | |
420a0d19 | 4244 | |
2ea97746 CE |
4245 | fl.auth_advertised = FALSE; |
4246 | f.smtp_in_pipelining_advertised = FALSE; | |
4247 | #ifdef SUPPORT_TLS | |
4248 | fl.tls_advertised = FALSE; | |
4249 | # ifdef EXPERIMENTAL_REQUIRETLS | |
4250 | fl.requiretls_advertised = FALSE; | |
4251 | # endif | |
4252 | #endif | |
4253 | fl.dsn_advertised = FALSE; | |
4254 | #ifdef SUPPORT_I18N | |
4255 | fl.smtputf8_advertised = FALSE; | |
4256 | #endif | |
420a0d19 | 4257 | |
2ea97746 CE |
4258 | smtp_code = US"250 "; /* Default response code plus space*/ |
4259 | if (!user_msg) | |
4260 | { | |
4261 | g = string_fmt_append(NULL, "%.3s %s Hello %s%s%s", | |
4262 | smtp_code, | |
4263 | smtp_active_hostname, | |
4264 | sender_ident ? sender_ident : US"", | |
4265 | sender_ident ? US" at " : US"", | |
4266 | sender_host_name ? sender_host_name : sender_helo_name); | |
4267 | ||
4268 | if (sender_host_address) | |
4269 | g = string_fmt_append(g, " [%s]", sender_host_address); | |
4270 | } | |
420a0d19 | 4271 | |
2ea97746 CE |
4272 | /* A user-supplied EHLO greeting may not contain more than one line. Note |
4273 | that the code returned by smtp_message_code() includes the terminating | |
4274 | whitespace character. */ | |
420a0d19 | 4275 | |
420a0d19 | 4276 | else |
2ea97746 CE |
4277 | { |
4278 | char *ss; | |
4279 | int codelen = 4; | |
4280 | smtp_message_code(&smtp_code, &codelen, &user_msg, NULL, TRUE); | |
4281 | s = string_sprintf("%.*s%s", codelen, smtp_code, user_msg); | |
4282 | if ((ss = strpbrk(CS s, "\r\n")) != NULL) | |
4283 | { | |
4284 | log_write(0, LOG_MAIN|LOG_PANIC, "EHLO/HELO response must not contain " | |
4285 | "newlines: message truncated: %s", string_printing(s)); | |
4286 | *ss = 0; | |
4287 | } | |
4288 | g = string_cat(NULL, s); | |
4289 | } | |
420a0d19 | 4290 | |
2ea97746 CE |
4291 | g = string_catn(g, US"\r\n", 2); |
4292 | ||
4293 | /* If we received EHLO, we must create a multiline response which includes | |
4294 | the functions supported. */ | |
4295 | ||
4296 | if (fl.esmtp) | |
4297 | { | |
4298 | g->s[3] = '-'; | |
4299 | ||
4300 | /* I'm not entirely happy with this, as an MTA is supposed to check | |
4301 | that it has enough room to accept a message of maximum size before | |
4302 | it sends this. However, there seems little point in not sending it. | |
4303 | The actual size check happens later at MAIL FROM time. By postponing it | |
4304 | till then, VRFY and EXPN can be used after EHLO when space is short. */ | |
4305 | ||
4306 | if (thismessage_size_limit > 0) | |
4307 | g = string_fmt_append(g, "%.3s-SIZE %d\r\n", smtp_code, | |
4308 | thismessage_size_limit); | |
4309 | else | |
4310 | { | |
4311 | g = string_catn(g, smtp_code, 3); | |
4312 | g = string_catn(g, US"-SIZE\r\n", 7); | |
4313 | } | |
4314 | ||
4315 | /* Exim does not do protocol conversion or data conversion. It is 8-bit | |
4316 | clean; if it has an 8-bit character in its hand, it just sends it. It | |
4317 | cannot therefore specify 8BITMIME and remain consistent with the RFCs. | |
4318 | However, some users want this option simply in order to stop MUAs | |
4319 | mangling messages that contain top-bit-set characters. It is therefore | |
4320 | provided as an option. */ | |
4321 | ||
4322 | if (accept_8bitmime) | |
4323 | { | |
4324 | g = string_catn(g, smtp_code, 3); | |
4325 | g = string_catn(g, US"-8BITMIME\r\n", 11); | |
4326 | } | |
4327 | ||
4328 | /* Advertise DSN support if configured to do so. */ | |
4329 | if (verify_check_host(&dsn_advertise_hosts) != FAIL) | |
4330 | { | |
4331 | g = string_catn(g, smtp_code, 3); | |
4332 | g = string_catn(g, US"-DSN\r\n", 6); | |
4333 | fl.dsn_advertised = TRUE; | |
4334 | } | |
4335 | ||
4336 | /* Advertise ETRN/VRFY/EXPN if there's are ACL checking whether a host is | |
4337 | permitted to issue them; a check is made when any host actually tries. */ | |
4338 | ||
4339 | if (acl_smtp_etrn) | |
4340 | { | |
4341 | g = string_catn(g, smtp_code, 3); | |
4342 | g = string_catn(g, US"-ETRN\r\n", 7); | |
4343 | } | |
4344 | if (acl_smtp_vrfy) | |
4345 | { | |
4346 | g = string_catn(g, smtp_code, 3); | |
4347 | g = string_catn(g, US"-VRFY\r\n", 7); | |
4348 | } | |
4349 | if (acl_smtp_expn) | |
4350 | { | |
4351 | g = string_catn(g, smtp_code, 3); | |
4352 | g = string_catn(g, US"-EXPN\r\n", 7); | |
4353 | } | |
4354 | ||
4355 | /* Exim is quite happy with pipelining, so let the other end know that | |
4356 | it is safe to use it, unless advertising is disabled. */ | |
4357 | ||
4358 | if ( f.pipelining_enable | |
4359 | && verify_check_host(&pipelining_advertise_hosts) == OK) | |
4360 | { | |
4361 | g = string_catn(g, smtp_code, 3); | |
4362 | g = string_catn(g, US"-PIPELINING\r\n", 13); | |
4363 | sync_cmd_limit = NON_SYNC_CMD_PIPELINING; | |
4364 | f.smtp_in_pipelining_advertised = TRUE; | |
4365 | ||
4366 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
4367 | if (fl.pipe_connect_acceptable) | |
4368 | { | |
4369 | f.smtp_in_early_pipe_advertised = TRUE; | |
4370 | g = string_catn(g, smtp_code, 3); | |
4371 | g = string_catn(g, US"-" EARLY_PIPE_FEATURE_NAME "\r\n", EARLY_PIPE_FEATURE_LEN+3); | |
4372 | } | |
4373 | #endif | |
4374 | } | |
420a0d19 | 4375 | |
420a0d19 | 4376 | |
2ea97746 CE |
4377 | /* If any server authentication mechanisms are configured, advertise |
4378 | them if the current host is in auth_advertise_hosts. The problem with | |
4379 | advertising always is that some clients then require users to | |
4380 | authenticate (and aren't configurable otherwise) even though it may not | |
4381 | be necessary (e.g. if the host is in host_accept_relay). | |
420a0d19 | 4382 | |
2ea97746 CE |
4383 | RFC 2222 states that SASL mechanism names contain only upper case |
4384 | letters, so output the names in upper case, though we actually recognize | |
4385 | them in either case in the AUTH command. */ | |
420a0d19 | 4386 | |
2ea97746 CE |
4387 | if ( auths |
4388 | #ifdef AUTH_TLS | |
4389 | && !sender_host_authenticated | |
4390 | #endif | |
4391 | && verify_check_host(&auth_advertise_hosts) == OK | |
4392 | ) | |
4393 | { | |
4394 | auth_instance *au; | |
4395 | BOOL first = TRUE; | |
4396 | for (au = auths; au; au = au->next) | |
4397 | { | |
4398 | au->advertised = FALSE; | |
4399 | if (au->server) | |
4400 | { | |
4401 | DEBUG(D_auth+D_expand) debug_printf_indent( | |
4402 | "Evaluating advertise_condition for %s athenticator\n", | |
4403 | au->public_name); | |
4404 | if ( !au->advertise_condition | |
4405 | || expand_check_condition(au->advertise_condition, au->name, | |
4406 | US"authenticator") | |
4407 | ) | |
4408 | { | |
4409 | int saveptr; | |
4410 | if (first) | |
4411 | { | |
4412 | g = string_catn(g, smtp_code, 3); | |
4413 | g = string_catn(g, US"-AUTH", 5); | |
4414 | first = FALSE; | |
4415 | fl.auth_advertised = TRUE; | |
4416 | } | |
4417 | saveptr = g->ptr; | |
4418 | g = string_catn(g, US" ", 1); | |
4419 | g = string_cat (g, au->public_name); | |
4420 | while (++saveptr < g->ptr) g->s[saveptr] = toupper(g->s[saveptr]); | |
4421 | au->advertised = TRUE; | |
4422 | } | |
4423 | } | |
4424 | } | |
4425 | ||
4426 | if (!first) g = string_catn(g, US"\r\n", 2); | |
4427 | } | |
4428 | ||
4429 | /* RFC 3030 CHUNKING */ | |
4430 | ||
4431 | if (verify_check_host(&chunking_advertise_hosts) != FAIL) | |
4432 | { | |
4433 | g = string_catn(g, smtp_code, 3); | |
4434 | g = string_catn(g, US"-CHUNKING\r\n", 11); | |
4435 | f.chunking_offered = TRUE; | |
4436 | chunking_state = CHUNKING_OFFERED; | |
4437 | } | |
4438 | ||
4439 | /* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer) | |
4440 | if it has been included in the binary, and the host matches | |
4441 | tls_advertise_hosts. We must *not* advertise if we are already in a | |
4442 | secure connection. */ | |
420a0d19 | 4443 | |
2ea97746 CE |
4444 | #ifdef SUPPORT_TLS |
4445 | if (tls_in.active.sock < 0 && | |
4446 | verify_check_host(&tls_advertise_hosts) != FAIL) | |
4447 | { | |
4448 | g = string_catn(g, smtp_code, 3); | |
4449 | g = string_catn(g, US"-STARTTLS\r\n", 11); | |
4450 | fl.tls_advertised = TRUE; | |
4451 | } | |
4452 | ||
4453 | # ifdef EXPERIMENTAL_REQUIRETLS | |
4454 | /* Advertise REQUIRETLS only once we are in a secure connection */ | |
4455 | if ( tls_in.active.sock >= 0 | |
4456 | && verify_check_host(&tls_advertise_requiretls) != FAIL) | |
4457 | { | |
4458 | g = string_catn(g, smtp_code, 3); | |
4459 | g = string_catn(g, US"-REQUIRETLS\r\n", 13); | |
4460 | fl.requiretls_advertised = TRUE; | |
4461 | } | |
4462 | # endif | |
4463 | #endif | |
420a0d19 | 4464 | |
2ea97746 CE |
4465 | #ifndef DISABLE_PRDR |
4466 | /* Per Recipient Data Response, draft by Eric A. Hall extending RFC */ | |
4467 | if (prdr_enable) | |
4468 | { | |
4469 | g = string_catn(g, smtp_code, 3); | |
4470 | g = string_catn(g, US"-PRDR\r\n", 7); | |
4471 | } | |
4472 | #endif | |
420a0d19 | 4473 | |
2ea97746 CE |
4474 | #ifdef SUPPORT_I18N |
4475 | if ( accept_8bitmime | |
4476 | && verify_check_host(&smtputf8_advertise_hosts) != FAIL) | |
4477 | { | |
4478 | g = string_catn(g, smtp_code, 3); | |
4479 | g = string_catn(g, US"-SMTPUTF8\r\n", 11); | |
4480 | fl.smtputf8_advertised = TRUE; | |
4481 | } | |
4482 | #endif | |
420a0d19 | 4483 | |
2ea97746 | 4484 | /* Finish off the multiline reply with one that is always available. */ |
420a0d19 | 4485 | |
2ea97746 CE |
4486 | g = string_catn(g, smtp_code, 3); |
4487 | g = string_catn(g, US" HELP\r\n", 7); | |
420a0d19 | 4488 | } |
420a0d19 | 4489 | |
2ea97746 CE |
4490 | /* Terminate the string (for debug), write it, and note that HELO/EHLO |
4491 | has been seen. */ | |
420a0d19 | 4492 | |
2ea97746 CE |
4493 | #ifdef SUPPORT_TLS |
4494 | if (tls_in.active.sock >= 0) | |
4495 | (void)tls_write(NULL, g->s, g->ptr, | |
4496 | # ifdef EXPERIMENTAL_PIPE_CONNECT | |
4497 | fl.pipe_connect_acceptable && pipeline_connect_sends()); | |
4498 | # else | |
4499 | FALSE); | |
4500 | # endif | |
4501 | else | |
4502 | #endif | |
420a0d19 | 4503 | |
2ea97746 CE |
4504 | { |
4505 | int i = fwrite(g->s, 1, g->ptr, smtp_out); i = i; /* compiler quietening */ | |
4506 | } | |
4507 | DEBUG(D_receive) | |
4508 | { | |
4509 | uschar *cr; | |
420a0d19 | 4510 | |
2ea97746 CE |
4511 | (void) string_from_gstring(g); |
4512 | while ((cr = Ustrchr(g->s, '\r')) != NULL) /* lose CRs */ | |
4513 | memmove(cr, cr + 1, (g->ptr--) - (cr - g->s)); | |
4514 | debug_printf("SMTP>> %s", g->s); | |
4515 | } | |
4516 | fl.helo_seen = TRUE; | |
4517 | ||
4518 | /* Reset the protocol and the state, abandoning any previous message. */ | |
4519 | received_protocol = | |
4520 | (sender_host_address ? protocols : protocols_local) | |
4521 | [ (fl.esmtp | |
4522 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
4523 | : pnormal) | |
4524 | + (tls_in.active.sock >= 0 ? pcrpted : 0) | |
4525 | ]; | |
4526 | cancel_cutthrough_connection(TRUE, US"sent EHLO response"); | |
4527 | smtp_reset(reset_point); | |
4528 | toomany = FALSE; | |
4529 | break; /* HELO/EHLO */ | |
420a0d19 CE |
4530 | |
4531 | ||
4532 | /* The MAIL command requires an address as an operand. All we do | |
4533 | here is to parse it for syntactic correctness. The form "<>" is | |
4534 | a special case which converts into an empty string. The start/end | |
4535 | pointers in the original are not used further for this address, as | |
4536 | it is the canonical extracted address which is all that is kept. */ | |
4537 | ||
4538 | case MAIL_CMD: | |
2ea97746 CE |
4539 | HAD(SCH_MAIL); |
4540 | smtp_mailcmd_count++; /* Count for limit and ratelimit */ | |
4541 | was_rej_mail = TRUE; /* Reset if accepted */ | |
4542 | env_mail_type_t * mail_args; /* Sanity check & validate args */ | |
4543 | ||
4544 | if (fl.helo_required && !fl.helo_seen) | |
4545 | { | |
4546 | smtp_printf("503 HELO or EHLO required\r\n", FALSE); | |
4547 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL from %s: no " | |
4548 | "HELO/EHLO given", host_and_ident(FALSE)); | |
4549 | break; | |
4550 | } | |
420a0d19 | 4551 | |
2ea97746 CE |
4552 | if (sender_address) |
4553 | { | |
4554 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
4555 | US"sender already given"); | |
4556 | break; | |
4557 | } | |
420a0d19 | 4558 | |
2ea97746 CE |
4559 | if (!*smtp_cmd_data) |
4560 | { | |
4561 | done = synprot_error(L_smtp_protocol_error, 501, NULL, | |
4562 | US"MAIL must have an address operand"); | |
4563 | break; | |
4564 | } | |
420a0d19 | 4565 | |
2ea97746 CE |
4566 | /* Check to see if the limit for messages per connection would be |
4567 | exceeded by accepting further messages. */ | |
420a0d19 | 4568 | |
2ea97746 CE |
4569 | if (smtp_accept_max_per_connection > 0 && |
4570 | smtp_mailcmd_count > smtp_accept_max_per_connection) | |
4571 | { | |
4572 | smtp_printf("421 too many messages in this connection\r\n", FALSE); | |
4573 | log_write(0, LOG_MAIN|LOG_REJECT, "rejected MAIL command %s: too many " | |
4574 | "messages in one connection", host_and_ident(TRUE)); | |
4575 | break; | |
4576 | } | |
420a0d19 | 4577 | |
2ea97746 CE |
4578 | /* Reset for start of message - even if this is going to fail, we |
4579 | obviously need to throw away any previous data. */ | |
420a0d19 | 4580 | |
2ea97746 CE |
4581 | cancel_cutthrough_connection(TRUE, US"MAIL received"); |
4582 | smtp_reset(reset_point); | |
4583 | toomany = FALSE; | |
4584 | sender_data = recipient_data = NULL; | |
420a0d19 | 4585 | |
2ea97746 | 4586 | /* Loop, checking for ESMTP additions to the MAIL FROM command. */ |
420a0d19 | 4587 | |
2ea97746 CE |
4588 | if (fl.esmtp) for(;;) |
4589 | { | |
4590 | uschar *name, *value, *end; | |
4591 | unsigned long int size; | |
4592 | BOOL arg_error = FALSE; | |
420a0d19 | 4593 | |
2ea97746 | 4594 | if (!extract_option(&name, &value)) break; |
420a0d19 | 4595 | |
2ea97746 CE |
4596 | for (mail_args = env_mail_type_list; |
4597 | mail_args->value != ENV_MAIL_OPT_NULL; | |
4598 | mail_args++ | |
4599 | ) | |
4600 | if (strcmpic(name, mail_args->name) == 0) | |
4601 | break; | |
4602 | if (mail_args->need_value && strcmpic(value, US"") == 0) | |
4603 | break; | |
4604 | ||
4605 | switch(mail_args->value) | |
4606 | { | |
4607 | /* Handle SIZE= by reading the value. We don't do the check till later, | |
4608 | in order to be able to log the sender address on failure. */ | |
4609 | case ENV_MAIL_OPT_SIZE: | |
4610 | if (((size = Ustrtoul(value, &end, 10)), *end == 0)) | |
4611 | { | |
4612 | if ((size == ULONG_MAX && errno == ERANGE) || size > INT_MAX) | |
4613 | size = INT_MAX; | |
4614 | message_size = (int)size; | |
4615 | } | |
4616 | else | |
4617 | arg_error = TRUE; | |
4618 | break; | |
420a0d19 | 4619 | |
2ea97746 CE |
4620 | /* If this session was initiated with EHLO and accept_8bitmime is set, |
4621 | Exim will have indicated that it supports the BODY=8BITMIME option. In | |
4622 | fact, it does not support this according to the RFCs, in that it does not | |
4623 | take any special action for forwarding messages containing 8-bit | |
4624 | characters. That is why accept_8bitmime is not the default setting, but | |
4625 | some sites want the action that is provided. We recognize both "8BITMIME" | |
4626 | and "7BIT" as body types, but take no action. */ | |
4627 | case ENV_MAIL_OPT_BODY: | |
4628 | if (accept_8bitmime) { | |
4629 | if (strcmpic(value, US"8BITMIME") == 0) | |
4630 | body_8bitmime = 8; | |
4631 | else if (strcmpic(value, US"7BIT") == 0) | |
4632 | body_8bitmime = 7; | |
4633 | else | |
4634 | { | |
4635 | body_8bitmime = 0; | |
4636 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4637 | US"invalid data for BODY"); | |
4638 | goto COMMAND_LOOP; | |
4639 | } | |
4640 | DEBUG(D_receive) debug_printf("8BITMIME: %d\n", body_8bitmime); | |
4641 | break; | |
4642 | } | |
4643 | arg_error = TRUE; | |
420a0d19 | 4644 | break; |
420a0d19 | 4645 | |
2ea97746 CE |
4646 | /* Handle the two DSN options, but only if configured to do so (which |
4647 | will have caused "DSN" to be given in the EHLO response). The code itself | |
4648 | is included only if configured in at build time. */ | |
4649 | ||
4650 | case ENV_MAIL_OPT_RET: | |
4651 | if (fl.dsn_advertised) | |
4652 | { | |
4653 | /* Check if RET has already been set */ | |
4654 | if (dsn_ret > 0) | |
4655 | { | |
4656 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4657 | US"RET can be specified once only"); | |
4658 | goto COMMAND_LOOP; | |
4659 | } | |
4660 | dsn_ret = strcmpic(value, US"HDRS") == 0 | |
4661 | ? dsn_ret_hdrs | |
4662 | : strcmpic(value, US"FULL") == 0 | |
4663 | ? dsn_ret_full | |
4664 | : 0; | |
4665 | DEBUG(D_receive) debug_printf("DSN_RET: %d\n", dsn_ret); | |
4666 | /* Check for invalid invalid value, and exit with error */ | |
4667 | if (dsn_ret == 0) | |
4668 | { | |
4669 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4670 | US"Value for RET is invalid"); | |
4671 | goto COMMAND_LOOP; | |
4672 | } | |
4673 | } | |
4674 | break; | |
4675 | case ENV_MAIL_OPT_ENVID: | |
4676 | if (fl.dsn_advertised) | |
4677 | { | |
4678 | /* Check if the dsn envid has been already set */ | |
4679 | if (dsn_envid) | |
4680 | { | |
4681 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4682 | US"ENVID can be specified once only"); | |
4683 | goto COMMAND_LOOP; | |
4684 | } | |
4685 | dsn_envid = string_copy(value); | |
4686 | DEBUG(D_receive) debug_printf("DSN_ENVID: %s\n", dsn_envid); | |
4687 | } | |
4688 | break; | |
420a0d19 | 4689 | |
2ea97746 CE |
4690 | /* Handle the AUTH extension. If the value given is not "<>" and either |
4691 | the ACL says "yes" or there is no ACL but the sending host is | |
4692 | authenticated, we set it up as the authenticated sender. However, if the | |
4693 | authenticator set a condition to be tested, we ignore AUTH on MAIL unless | |
4694 | the condition is met. The value of AUTH is an xtext, which means that +, | |
4695 | = and cntrl chars are coded in hex; however "<>" is unaffected by this | |
4696 | coding. */ | |
4697 | case ENV_MAIL_OPT_AUTH: | |
4698 | if (Ustrcmp(value, "<>") != 0) | |
4699 | { | |
4700 | int rc; | |
4701 | uschar *ignore_msg; | |
4702 | ||
4703 | if (auth_xtextdecode(value, &authenticated_sender) < 0) | |
4704 | { | |
4705 | /* Put back terminator overrides for error message */ | |
4706 | value[-1] = '='; | |
4707 | name[-1] = ' '; | |
4708 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4709 | US"invalid data for AUTH"); | |
4710 | goto COMMAND_LOOP; | |
4711 | } | |
4712 | if (!acl_smtp_mailauth) | |
4713 | { | |
4714 | ignore_msg = US"client not authenticated"; | |
4715 | rc = sender_host_authenticated ? OK : FAIL; | |
4716 | } | |
4717 | else | |
4718 | { | |
4719 | ignore_msg = US"rejected by ACL"; | |
4720 | rc = acl_check(ACL_WHERE_MAILAUTH, NULL, acl_smtp_mailauth, | |
4721 | &user_msg, &log_msg); | |
4722 | } | |
4723 | ||
4724 | switch (rc) | |
4725 | { | |
4726 | case OK: | |
4727 | if (authenticated_by == NULL || | |
4728 | authenticated_by->mail_auth_condition == NULL || | |
4729 | expand_check_condition(authenticated_by->mail_auth_condition, | |
4730 | authenticated_by->name, US"authenticator")) | |
4731 | break; /* Accept the AUTH */ | |
4732 | ||
4733 | ignore_msg = US"server_mail_auth_condition failed"; | |
4734 | if (authenticated_id != NULL) | |
4735 | ignore_msg = string_sprintf("%s: authenticated ID=\"%s\"", | |
4736 | ignore_msg, authenticated_id); | |
4737 | ||
4738 | /* Fall through */ | |
4739 | ||
4740 | case FAIL: | |
4741 | authenticated_sender = NULL; | |
4742 | log_write(0, LOG_MAIN, "ignoring AUTH=%s from %s (%s)", | |
4743 | value, host_and_ident(TRUE), ignore_msg); | |
4744 | break; | |
4745 | ||
4746 | /* Should only get DEFER or ERROR here. Put back terminator | |
4747 | overrides for error message */ | |
4748 | ||
4749 | default: | |
4750 | value[-1] = '='; | |
4751 | name[-1] = ' '; | |
4752 | (void)smtp_handle_acl_fail(ACL_WHERE_MAILAUTH, rc, user_msg, | |
4753 | log_msg); | |
4754 | goto COMMAND_LOOP; | |
4755 | } | |
4756 | } | |
4757 | break; | |
420a0d19 CE |
4758 | |
4759 | #ifndef DISABLE_PRDR | |
2ea97746 CE |
4760 | case ENV_MAIL_OPT_PRDR: |
4761 | if (prdr_enable) | |
4762 | prdr_requested = TRUE; | |
4763 | break; | |
420a0d19 CE |
4764 | #endif |
4765 | ||
2ea97746 CE |
4766 | #ifdef SUPPORT_I18N |
4767 | case ENV_MAIL_OPT_UTF8: | |
4768 | if (!fl.smtputf8_advertised) | |
4769 | { | |
4770 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
4771 | US"SMTPUTF8 used when not advertised"); | |
4772 | goto COMMAND_LOOP; | |
4773 | } | |
4774 | ||
4775 | DEBUG(D_receive) debug_printf("smtputf8 requested\n"); | |
4776 | message_smtputf8 = allow_utf8_domains = TRUE; | |
4777 | if (Ustrncmp(received_protocol, US"utf8", 4) != 0) | |
4778 | { | |
4779 | int old_pool = store_pool; | |
4780 | store_pool = POOL_PERM; | |
4781 | received_protocol = string_sprintf("utf8%s", received_protocol); | |
4782 | store_pool = old_pool; | |
4783 | } | |
4784 | break; | |
4785 | #endif | |
420a0d19 | 4786 | |
2ea97746 CE |
4787 | #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS) |
4788 | case ENV_MAIL_OPT_REQTLS: | |
4789 | { | |
4790 | uschar * r, * t; | |
4791 | ||
4792 | if (!fl.requiretls_advertised) | |
4793 | { | |
4794 | done = synprot_error(L_smtp_syntax_error, 555, NULL, | |
4795 | US"unadvertised MAIL option: REQUIRETLS"); | |
4796 | goto COMMAND_LOOP; | |
4797 | } | |
4798 | ||
4799 | DEBUG(D_receive) debug_printf("requiretls requested\n"); | |
4800 | tls_requiretls = REQUIRETLS_MSG; | |
4801 | ||
4802 | r = string_copy_malloc(received_protocol); | |
4803 | if ((t = Ustrrchr(r, 's'))) *t = 'S'; | |
4804 | received_protocol = r; | |
4805 | } | |
4806 | break; | |
4807 | #endif | |
420a0d19 | 4808 | |
2ea97746 CE |
4809 | /* No valid option. Stick back the terminator characters and break |
4810 | the loop. Do the name-terminator second as extract_option sets | |
4811 | value==name when it found no equal-sign. | |
4812 | An error for a malformed address will occur. */ | |
4813 | case ENV_MAIL_OPT_NULL: | |
4814 | value[-1] = '='; | |
4815 | name[-1] = ' '; | |
4816 | arg_error = TRUE; | |
4817 | break; | |
420a0d19 | 4818 | |
2ea97746 CE |
4819 | default: assert(0); |
4820 | } | |
4821 | /* Break out of for loop if switch() had bad argument or | |
4822 | when start of the email address is reached */ | |
4823 | if (arg_error) break; | |
4824 | } | |
420a0d19 | 4825 | |
2ea97746 CE |
4826 | #if defined(SUPPORT_TLS) && defined(EXPERIMENTAL_REQUIRETLS) |
4827 | if (tls_requiretls & REQUIRETLS_MSG) | |
4828 | { | |
4829 | /* Ensure headers-only bounces whether a RET option was given or not. */ | |
420a0d19 | 4830 | |
2ea97746 CE |
4831 | DEBUG(D_receive) if (dsn_ret == dsn_ret_full) |
4832 | debug_printf("requiretls override: dsn_ret_full -> dsn_ret_hdrs\n"); | |
4833 | dsn_ret = dsn_ret_hdrs; | |
4834 | } | |
4835 | #endif | |
420a0d19 | 4836 | |
2ea97746 CE |
4837 | /* If we have passed the threshold for rate limiting, apply the current |
4838 | delay, and update it for next time, provided this is a limited host. */ | |
4839 | ||
4840 | if (smtp_mailcmd_count > smtp_rlm_threshold && | |
4841 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
4842 | { | |
4843 | DEBUG(D_receive) debug_printf("rate limit MAIL: delay %.3g sec\n", | |
4844 | smtp_delay_mail/1000.0); | |
4845 | millisleep((int)smtp_delay_mail); | |
4846 | smtp_delay_mail *= smtp_rlm_factor; | |
4847 | if (smtp_delay_mail > (double)smtp_rlm_limit) | |
4848 | smtp_delay_mail = (double)smtp_rlm_limit; | |
4849 | } | |
420a0d19 | 4850 | |
2ea97746 CE |
4851 | /* Now extract the address, first applying any SMTP-time rewriting. The |
4852 | TRUE flag allows "<>" as a sender address. */ | |
420a0d19 | 4853 | |
2ea97746 CE |
4854 | raw_sender = rewrite_existflags & rewrite_smtp |
4855 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
4856 | global_rewrite_rules) | |
4857 | : smtp_cmd_data; | |
420a0d19 | 4858 | |
2ea97746 CE |
4859 | raw_sender = |
4860 | parse_extract_address(raw_sender, &errmess, &start, &end, &sender_domain, | |
4861 | TRUE); | |
420a0d19 | 4862 | |
2ea97746 CE |
4863 | if (!raw_sender) |
4864 | { | |
4865 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); | |
4866 | break; | |
4867 | } | |
420a0d19 | 4868 | |
2ea97746 CE |
4869 | sender_address = raw_sender; |
4870 | ||
4871 | /* If there is a configured size limit for mail, check that this message | |
4872 | doesn't exceed it. The check is postponed to this point so that the sender | |
4873 | can be logged. */ | |
4874 | ||
4875 | if (thismessage_size_limit > 0 && message_size > thismessage_size_limit) | |
4876 | { | |
4877 | smtp_printf("552 Message size exceeds maximum permitted\r\n", FALSE); | |
4878 | log_write(L_size_reject, | |
4879 | LOG_MAIN|LOG_REJECT, "rejected MAIL FROM:<%s> %s: " | |
4880 | "message too big: size%s=%d max=%d", | |
4881 | sender_address, | |
4882 | host_and_ident(TRUE), | |
4883 | (message_size == INT_MAX)? ">" : "", | |
4884 | message_size, | |
4885 | thismessage_size_limit); | |
4886 | sender_address = NULL; | |
4887 | break; | |
4888 | } | |
420a0d19 | 4889 | |
2ea97746 CE |
4890 | /* Check there is enough space on the disk unless configured not to. |
4891 | When smtp_check_spool_space is set, the check is for thismessage_size_limit | |
4892 | plus the current message - i.e. we accept the message only if it won't | |
4893 | reduce the space below the threshold. Add 5000 to the size to allow for | |
4894 | overheads such as the Received: line and storing of recipients, etc. | |
4895 | By putting the check here, even when SIZE is not given, it allow VRFY | |
4896 | and EXPN etc. to be used when space is short. */ | |
4897 | ||
4898 | if (!receive_check_fs( | |
4899 | (smtp_check_spool_space && message_size >= 0)? | |
4900 | message_size + 5000 : 0)) | |
4901 | { | |
4902 | smtp_printf("452 Space shortage, please try later\r\n", FALSE); | |
4903 | sender_address = NULL; | |
4904 | break; | |
4905 | } | |
420a0d19 | 4906 | |
2ea97746 CE |
4907 | /* If sender_address is unqualified, reject it, unless this is a locally |
4908 | generated message, or the sending host or net is permitted to send | |
4909 | unqualified addresses - typically local machines behaving as MUAs - | |
4910 | in which case just qualify the address. The flag is set above at the start | |
4911 | of the SMTP connection. */ | |
4912 | ||
4913 | if (!sender_domain && *sender_address) | |
4914 | if (f.allow_unqualified_sender) | |
4915 | { | |
4916 | sender_domain = Ustrlen(sender_address) + 1; | |
4917 | sender_address = rewrite_address_qualify(sender_address, FALSE); | |
4918 | DEBUG(D_receive) debug_printf("unqualified address %s accepted\n", | |
4919 | raw_sender); | |
4920 | } | |
4921 | else | |
4922 | { | |
4923 | smtp_printf("501 %s: sender address must contain a domain\r\n", FALSE, | |
4924 | smtp_cmd_data); | |
4925 | log_write(L_smtp_syntax_error, | |
4926 | LOG_MAIN|LOG_REJECT, | |
4927 | "unqualified sender rejected: <%s> %s%s", | |
4928 | raw_sender, | |
4929 | host_and_ident(TRUE), | |
4930 | host_lookup_msg); | |
4931 | sender_address = NULL; | |
4932 | break; | |
4933 | } | |
4934 | ||
4935 | /* Apply an ACL check if one is defined, before responding. Afterwards, | |
4936 | when pipelining is not advertised, do another sync check in case the ACL | |
4937 | delayed and the client started sending in the meantime. */ | |
4938 | ||
4939 | if (acl_smtp_mail) | |
4940 | { | |
4941 | rc = acl_check(ACL_WHERE_MAIL, NULL, acl_smtp_mail, &user_msg, &log_msg); | |
4942 | if (rc == OK && !f.smtp_in_pipelining_advertised && !check_sync()) | |
4943 | goto SYNC_FAILURE; | |
4944 | } | |
4945 | else | |
4946 | rc = OK; | |
4947 | ||
4948 | if (rc == OK || rc == DISCARD) | |
4949 | { | |
4950 | BOOL more = pipeline_response(); | |
4951 | ||
4952 | if (!user_msg) | |
4953 | smtp_printf("%s%s%s", more, US"250 OK", | |
4954 | #ifndef DISABLE_PRDR | |
4955 | prdr_requested ? US", PRDR Requested" : US"", | |
4956 | #else | |
4957 | US"", | |
4958 | #endif | |
4959 | US"\r\n"); | |
4960 | else | |
4961 | { | |
4962 | #ifndef DISABLE_PRDR | |
4963 | if (prdr_requested) | |
4964 | user_msg = string_sprintf("%s%s", user_msg, US", PRDR Requested"); | |
4965 | #endif | |
4966 | smtp_user_msg(US"250", user_msg); | |
4967 | } | |
4968 | smtp_delay_rcpt = smtp_rlr_base; | |
4969 | f.recipients_discarded = (rc == DISCARD); | |
4970 | was_rej_mail = FALSE; | |
4971 | } | |
4972 | else | |
4973 | { | |
4974 | done = smtp_handle_acl_fail(ACL_WHERE_MAIL, rc, user_msg, log_msg); | |
4975 | sender_address = NULL; | |
4976 | } | |
4977 | break; | |
420a0d19 CE |
4978 | |
4979 | ||
4980 | /* The RCPT command requires an address as an operand. There may be any | |
4981 | number of RCPT commands, specifying multiple recipients. We build them all | |
4982 | into a data structure. The start/end values given by parse_extract_address | |
4983 | are not used, as we keep only the extracted address. */ | |
4984 | ||
4985 | case RCPT_CMD: | |
2ea97746 CE |
4986 | HAD(SCH_RCPT); |
4987 | rcpt_count++; | |
4988 | was_rcpt = fl.rcpt_in_progress = TRUE; | |
420a0d19 | 4989 | |
2ea97746 CE |
4990 | /* There must be a sender address; if the sender was rejected and |
4991 | pipelining was advertised, we assume the client was pipelining, and do not | |
4992 | count this as a protocol error. Reset was_rej_mail so that further RCPTs | |
4993 | get the same treatment. */ | |
420a0d19 | 4994 | |
2ea97746 CE |
4995 | if (sender_address == NULL) |
4996 | { | |
4997 | if (f.smtp_in_pipelining_advertised && last_was_rej_mail) | |
4998 | { | |
4999 | smtp_printf("503 sender not yet given\r\n", FALSE); | |
5000 | was_rej_mail = TRUE; | |
5001 | } | |
5002 | else | |
5003 | { | |
5004 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5005 | US"sender not yet given"); | |
5006 | was_rcpt = FALSE; /* Not a valid RCPT */ | |
5007 | } | |
5008 | rcpt_fail_count++; | |
5009 | break; | |
5010 | } | |
420a0d19 | 5011 | |
2ea97746 | 5012 | /* Check for an operand */ |
420a0d19 | 5013 | |
2ea97746 CE |
5014 | if (smtp_cmd_data[0] == 0) |
5015 | { | |
5016 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5017 | US"RCPT must have an address operand"); | |
5018 | rcpt_fail_count++; | |
5019 | break; | |
5020 | } | |
420a0d19 | 5021 | |
2ea97746 CE |
5022 | /* Set the DSN flags orcpt and dsn_flags from the session*/ |
5023 | orcpt = NULL; | |
5024 | dsn_flags = 0; | |
5025 | ||
5026 | if (fl.esmtp) for(;;) | |
5027 | { | |
5028 | uschar *name, *value; | |
5029 | ||
5030 | if (!extract_option(&name, &value)) | |
5031 | break; | |
5032 | ||
5033 | if (fl.dsn_advertised && strcmpic(name, US"ORCPT") == 0) | |
5034 | { | |
5035 | /* Check whether orcpt has been already set */ | |
5036 | if (orcpt) | |
5037 | { | |
5038 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5039 | US"ORCPT can be specified once only"); | |
5040 | goto COMMAND_LOOP; | |
5041 | } | |
5042 | orcpt = string_copy(value); | |
5043 | DEBUG(D_receive) debug_printf("DSN orcpt: %s\n", orcpt); | |
5044 | } | |
5045 | ||
5046 | else if (fl.dsn_advertised && strcmpic(name, US"NOTIFY") == 0) | |
5047 | { | |
5048 | /* Check if the notify flags have been already set */ | |
5049 | if (dsn_flags > 0) | |
5050 | { | |
5051 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5052 | US"NOTIFY can be specified once only"); | |
5053 | goto COMMAND_LOOP; | |
5054 | } | |
5055 | if (strcmpic(value, US"NEVER") == 0) | |
5056 | dsn_flags |= rf_notify_never; | |
5057 | else | |
5058 | { | |
5059 | uschar *p = value; | |
5060 | while (*p != 0) | |
5061 | { | |
5062 | uschar *pp = p; | |
5063 | while (*pp != 0 && *pp != ',') pp++; | |
5064 | if (*pp == ',') *pp++ = 0; | |
5065 | if (strcmpic(p, US"SUCCESS") == 0) | |
5066 | { | |
5067 | DEBUG(D_receive) debug_printf("DSN: Setting notify success\n"); | |
5068 | dsn_flags |= rf_notify_success; | |
5069 | } | |
5070 | else if (strcmpic(p, US"FAILURE") == 0) | |
5071 | { | |
5072 | DEBUG(D_receive) debug_printf("DSN: Setting notify failure\n"); | |
5073 | dsn_flags |= rf_notify_failure; | |
5074 | } | |
5075 | else if (strcmpic(p, US"DELAY") == 0) | |
5076 | { | |
5077 | DEBUG(D_receive) debug_printf("DSN: Setting notify delay\n"); | |
5078 | dsn_flags |= rf_notify_delay; | |
5079 | } | |
5080 | else | |
5081 | { | |
5082 | /* Catch any strange values */ | |
5083 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5084 | US"Invalid value for NOTIFY parameter"); | |
5085 | goto COMMAND_LOOP; | |
5086 | } | |
5087 | p = pp; | |
5088 | } | |
5089 | DEBUG(D_receive) debug_printf("DSN Flags: %x\n", dsn_flags); | |
5090 | } | |
5091 | } | |
5092 | ||
5093 | /* Unknown option. Stick back the terminator characters and break | |
5094 | the loop. An error for a malformed address will occur. */ | |
5095 | ||
5096 | else | |
5097 | { | |
5098 | DEBUG(D_receive) debug_printf("Invalid RCPT option: %s : %s\n", name, value); | |
5099 | name[-1] = ' '; | |
5100 | value[-1] = '='; | |
5101 | break; | |
5102 | } | |
5103 | } | |
420a0d19 | 5104 | |
2ea97746 CE |
5105 | /* Apply SMTP rewriting then extract the working address. Don't allow "<>" |
5106 | as a recipient address */ | |
420a0d19 | 5107 | |
2ea97746 CE |
5108 | recipient = rewrite_existflags & rewrite_smtp |
5109 | ? rewrite_one(smtp_cmd_data, rewrite_smtp, NULL, FALSE, US"", | |
5110 | global_rewrite_rules) | |
5111 | : smtp_cmd_data; | |
420a0d19 | 5112 | |
2ea97746 CE |
5113 | if (!(recipient = parse_extract_address(recipient, &errmess, &start, &end, |
5114 | &recipient_domain, FALSE))) | |
5115 | { | |
5116 | done = synprot_error(L_smtp_syntax_error, 501, smtp_cmd_data, errmess); | |
5117 | rcpt_fail_count++; | |
5118 | break; | |
5119 | } | |
420a0d19 | 5120 | |
2ea97746 CE |
5121 | /* If the recipient address is unqualified, reject it, unless this is a |
5122 | locally generated message. However, unqualified addresses are permitted | |
5123 | from a configured list of hosts and nets - typically when behaving as | |
5124 | MUAs rather than MTAs. Sad that SMTP is used for both types of traffic, | |
5125 | really. The flag is set at the start of the SMTP connection. | |
5126 | ||
5127 | RFC 1123 talks about supporting "the reserved mailbox postmaster"; I always | |
5128 | assumed this meant "reserved local part", but the revision of RFC 821 and | |
5129 | friends now makes it absolutely clear that it means *mailbox*. Consequently | |
5130 | we must always qualify this address, regardless. */ | |
5131 | ||
5132 | if (!recipient_domain) | |
5133 | if (!(recipient_domain = qualify_recipient(&recipient, smtp_cmd_data, | |
5134 | US"recipient"))) | |
5135 | { | |
5136 | rcpt_fail_count++; | |
5137 | break; | |
5138 | } | |
5139 | ||
5140 | /* Check maximum allowed */ | |
5141 | ||
5142 | if (rcpt_count > recipients_max && recipients_max > 0) | |
5143 | { | |
5144 | if (recipients_max_reject) | |
5145 | { | |
5146 | rcpt_fail_count++; | |
5147 | smtp_printf("552 too many recipients\r\n", FALSE); | |
5148 | if (!toomany) | |
5149 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: message " | |
5150 | "rejected: sender=<%s> %s", sender_address, host_and_ident(TRUE)); | |
5151 | } | |
5152 | else | |
5153 | { | |
5154 | rcpt_defer_count++; | |
5155 | smtp_printf("452 too many recipients\r\n", FALSE); | |
5156 | if (!toomany) | |
5157 | log_write(0, LOG_MAIN|LOG_REJECT, "too many recipients: excess " | |
5158 | "temporarily rejected: sender=<%s> %s", sender_address, | |
5159 | host_and_ident(TRUE)); | |
5160 | } | |
5161 | ||
5162 | toomany = TRUE; | |
5163 | break; | |
5164 | } | |
420a0d19 | 5165 | |
2ea97746 CE |
5166 | /* If we have passed the threshold for rate limiting, apply the current |
5167 | delay, and update it for next time, provided this is a limited host. */ | |
5168 | ||
5169 | if (rcpt_count > smtp_rlr_threshold && | |
5170 | verify_check_host(&smtp_ratelimit_hosts) == OK) | |
5171 | { | |
5172 | DEBUG(D_receive) debug_printf("rate limit RCPT: delay %.3g sec\n", | |
5173 | smtp_delay_rcpt/1000.0); | |
5174 | millisleep((int)smtp_delay_rcpt); | |
5175 | smtp_delay_rcpt *= smtp_rlr_factor; | |
5176 | if (smtp_delay_rcpt > (double)smtp_rlr_limit) | |
5177 | smtp_delay_rcpt = (double)smtp_rlr_limit; | |
5178 | } | |
420a0d19 | 5179 | |
2ea97746 CE |
5180 | /* If the MAIL ACL discarded all the recipients, we bypass ACL checking |
5181 | for them. Otherwise, check the access control list for this recipient. As | |
5182 | there may be a delay in this, re-check for a synchronization error | |
5183 | afterwards, unless pipelining was advertised. */ | |
420a0d19 | 5184 | |
2ea97746 CE |
5185 | if (f.recipients_discarded) |
5186 | rc = DISCARD; | |
5187 | else | |
5188 | if ( (rc = acl_check(ACL_WHERE_RCPT, recipient, acl_smtp_rcpt, &user_msg, | |
5189 | &log_msg)) == OK | |
5190 | && !f.smtp_in_pipelining_advertised && !check_sync()) | |
5191 | goto SYNC_FAILURE; | |
5192 | ||
5193 | /* The ACL was happy */ | |
5194 | ||
5195 | if (rc == OK) | |
5196 | { | |
5197 | BOOL more = pipeline_response(); | |
5198 | ||
5199 | if (user_msg) | |
5200 | smtp_user_msg(US"250", user_msg); | |
5201 | else | |
5202 | smtp_printf("250 Accepted\r\n", more); | |
5203 | receive_add_recipient(recipient, -1); | |
5204 | ||
5205 | /* Set the dsn flags in the recipients_list */ | |
5206 | recipients_list[recipients_count-1].orcpt = orcpt; | |
5207 | recipients_list[recipients_count-1].dsn_flags = dsn_flags; | |
5208 | ||
5209 | DEBUG(D_receive) debug_printf("DSN: orcpt: %s flags: %d\n", | |
5210 | recipients_list[recipients_count-1].orcpt, | |
5211 | recipients_list[recipients_count-1].dsn_flags); | |
5212 | } | |
420a0d19 | 5213 | |
2ea97746 CE |
5214 | /* The recipient was discarded */ |
5215 | ||
5216 | else if (rc == DISCARD) | |
5217 | { | |
5218 | if (user_msg) | |
5219 | smtp_user_msg(US"250", user_msg); | |
5220 | else | |
5221 | smtp_printf("250 Accepted\r\n", FALSE); | |
5222 | rcpt_fail_count++; | |
5223 | discarded = TRUE; | |
5224 | log_write(0, LOG_MAIN|LOG_REJECT, "%s F=<%s> RCPT %s: " | |
5225 | "discarded by %s ACL%s%s", host_and_ident(TRUE), | |
5226 | sender_address_unrewritten? sender_address_unrewritten : sender_address, | |
5227 | smtp_cmd_argument, f.recipients_discarded? "MAIL" : "RCPT", | |
5228 | log_msg ? US": " : US"", log_msg ? log_msg : US""); | |
5229 | } | |
420a0d19 | 5230 | |
2ea97746 CE |
5231 | /* Either the ACL failed the address, or it was deferred. */ |
5232 | ||
5233 | else | |
5234 | { | |
5235 | if (rc == FAIL) rcpt_fail_count++; else rcpt_defer_count++; | |
5236 | done = smtp_handle_acl_fail(ACL_WHERE_RCPT, rc, user_msg, log_msg); | |
5237 | } | |
5238 | break; | |
420a0d19 CE |
5239 | |
5240 | ||
5241 | /* The DATA command is legal only if it follows successful MAIL FROM | |
5242 | and RCPT TO commands. However, if pipelining is advertised, a bad DATA is | |
5243 | not counted as a protocol error if it follows RCPT (which must have been | |
5244 | rejected if there are no recipients.) This function is complete when a | |
5245 | valid DATA command is encountered. | |
5246 | ||
5247 | Note concerning the code used: RFC 2821 says this: | |
5248 | ||
5249 | - If there was no MAIL, or no RCPT, command, or all such commands | |
5250 | were rejected, the server MAY return a "command out of sequence" | |
5251 | (503) or "no valid recipients" (554) reply in response to the | |
5252 | DATA command. | |
5253 | ||
5254 | The example in the pipelining RFC 2920 uses 554, but I use 503 here | |
5255 | because it is the same whether pipelining is in use or not. | |
5256 | ||
5257 | If all the RCPT commands that precede DATA provoked the same error message | |
5258 | (often indicating some kind of system error), it is helpful to include it | |
5259 | with the DATA rejection (an idea suggested by Tony Finch). */ | |
5260 | ||
2ea97746 | 5261 | case BDAT_CMD: |
420a0d19 | 5262 | { |
2ea97746 CE |
5263 | int n; |
5264 | ||
5265 | HAD(SCH_BDAT); | |
5266 | if (chunking_state != CHUNKING_OFFERED) | |
5267 | { | |
5268 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5269 | US"BDAT command used when CHUNKING not advertised"); | |
5270 | break; | |
5271 | } | |
420a0d19 | 5272 | |
2ea97746 | 5273 | /* grab size, endmarker */ |
420a0d19 | 5274 | |
2ea97746 CE |
5275 | if (sscanf(CS smtp_cmd_data, "%u %n", &chunking_datasize, &n) < 1) |
5276 | { | |
5277 | done = synprot_error(L_smtp_protocol_error, 501, NULL, | |
5278 | US"missing size for BDAT command"); | |
5279 | break; | |
5280 | } | |
5281 | chunking_state = strcmpic(smtp_cmd_data+n, US"LAST") == 0 | |
5282 | ? CHUNKING_LAST : CHUNKING_ACTIVE; | |
5283 | chunking_data_left = chunking_datasize; | |
5284 | DEBUG(D_receive) debug_printf("chunking state %d, %d bytes\n", | |
5285 | (int)chunking_state, chunking_data_left); | |
420a0d19 | 5286 | |
2ea97746 CE |
5287 | /* push the current receive_* function on the "stack", and |
5288 | replace them by bdat_getc(), which in turn will use the lwr_receive_* | |
5289 | functions to do the dirty work. */ | |
5290 | lwr_receive_getc = receive_getc; | |
5291 | lwr_receive_getbuf = receive_getbuf; | |
5292 | lwr_receive_ungetc = receive_ungetc; | |
420a0d19 | 5293 | |
2ea97746 CE |
5294 | receive_getc = bdat_getc; |
5295 | receive_ungetc = bdat_ungetc; | |
420a0d19 | 5296 | |
2ea97746 | 5297 | f.dot_ends = FALSE; |
420a0d19 | 5298 | |
2ea97746 CE |
5299 | goto DATA_BDAT; |
5300 | } | |
420a0d19 | 5301 | |
2ea97746 CE |
5302 | case DATA_CMD: |
5303 | HAD(SCH_DATA); | |
5304 | f.dot_ends = TRUE; | |
420a0d19 | 5305 | |
2ea97746 CE |
5306 | DATA_BDAT: /* Common code for DATA and BDAT */ |
5307 | #ifdef EXPERIMENTAL_PIPE_CONNECT | |
5308 | fl.pipe_connect_acceptable = FALSE; | |
5309 | #endif | |
5310 | if (!discarded && recipients_count <= 0) | |
5311 | { | |
5312 | if (fl.rcpt_smtp_response_same && rcpt_smtp_response != NULL) | |
5313 | { | |
5314 | uschar *code = US"503"; | |
5315 | int len = Ustrlen(rcpt_smtp_response); | |
5316 | smtp_respond(code, 3, FALSE, US"All RCPT commands were rejected with " | |
5317 | "this error:"); | |
5318 | /* Responses from smtp_printf() will have \r\n on the end */ | |
5319 | if (len > 2 && rcpt_smtp_response[len-2] == '\r') | |
5320 | rcpt_smtp_response[len-2] = 0; | |
5321 | smtp_respond(code, 3, FALSE, rcpt_smtp_response); | |
5322 | } | |
5323 | if (f.smtp_in_pipelining_advertised && last_was_rcpt) | |
5324 | smtp_printf("503 Valid RCPT command must precede %s\r\n", FALSE, | |
5325 | smtp_names[smtp_connection_had[smtp_ch_index-1]]); | |
5326 | else | |
5327 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5328 | smtp_connection_had[smtp_ch_index-1] == SCH_DATA | |
5329 | ? US"valid RCPT command must precede DATA" | |
5330 | : US"valid RCPT command must precede BDAT"); | |
5331 | ||
5332 | if (chunking_state > CHUNKING_OFFERED) | |
5333 | bdat_flush_data(); | |
5334 | break; | |
5335 | } | |
420a0d19 | 5336 | |
2ea97746 CE |
5337 | if (toomany && recipients_max_reject) |
5338 | { | |
5339 | sender_address = NULL; /* This will allow a new MAIL without RSET */ | |
5340 | sender_address_unrewritten = NULL; | |
5341 | smtp_printf("554 Too many recipients\r\n", FALSE); | |
5342 | break; | |
5343 | } | |
420a0d19 | 5344 | |
2ea97746 CE |
5345 | if (chunking_state > CHUNKING_OFFERED) |
5346 | rc = OK; /* No predata ACL or go-ahead output for BDAT */ | |
420a0d19 | 5347 | else |
2ea97746 CE |
5348 | { |
5349 | /* If there is an ACL, re-check the synchronization afterwards, since the | |
5350 | ACL may have delayed. To handle cutthrough delivery enforce a dummy call | |
5351 | to get the DATA command sent. */ | |
5352 | ||
5353 | if (acl_smtp_predata == NULL && cutthrough.cctx.sock < 0) | |
5354 | rc = OK; | |
5355 | else | |
5356 | { | |
5357 | uschar * acl = acl_smtp_predata ? acl_smtp_predata : US"accept"; | |
5358 | f.enable_dollar_recipients = TRUE; | |
5359 | rc = acl_check(ACL_WHERE_PREDATA, NULL, acl, &user_msg, | |
5360 | &log_msg); | |
5361 | f.enable_dollar_recipients = FALSE; | |
5362 | if (rc == OK && !check_sync()) | |
5363 | goto SYNC_FAILURE; | |
5364 | ||
5365 | if (rc != OK) | |
5366 | { /* Either the ACL failed the address, or it was deferred. */ | |
5367 | done = smtp_handle_acl_fail(ACL_WHERE_PREDATA, rc, user_msg, log_msg); | |
5368 | break; | |
5369 | } | |
5370 | } | |
5371 | ||
5372 | if (user_msg) | |
5373 | smtp_user_msg(US"354", user_msg); | |
5374 | else | |
5375 | smtp_printf( | |
5376 | "354 Enter message, ending with \".\" on a line by itself\r\n", FALSE); | |
5377 | } | |
420a0d19 | 5378 | |
2ea97746 CE |
5379 | #ifdef TCP_QUICKACK |
5380 | if (smtp_in) /* all ACKs needed to ramp window up for bulk data */ | |
5381 | (void) setsockopt(fileno(smtp_in), IPPROTO_TCP, TCP_QUICKACK, | |
5382 | US &on, sizeof(on)); | |
5383 | #endif | |
5384 | done = 3; | |
5385 | message_ended = END_NOTENDED; /* Indicate in middle of data */ | |
420a0d19 | 5386 | |
2ea97746 | 5387 | break; |
420a0d19 CE |
5388 | |
5389 | ||
2ea97746 | 5390 | case VRFY_CMD: |
420a0d19 | 5391 | { |
2ea97746 | 5392 | uschar * address; |
420a0d19 | 5393 | |
2ea97746 | 5394 | HAD(SCH_VRFY); |
420a0d19 | 5395 | |
2ea97746 CE |
5396 | if (!(address = parse_extract_address(smtp_cmd_data, &errmess, |
5397 | &start, &end, &recipient_domain, FALSE))) | |
5398 | { | |
5399 | smtp_printf("501 %s\r\n", FALSE, errmess); | |
5400 | break; | |
5401 | } | |
420a0d19 | 5402 | |
2ea97746 CE |
5403 | if (!recipient_domain) |
5404 | if (!(recipient_domain = qualify_recipient(&address, smtp_cmd_data, | |
5405 | US"verify"))) | |
5406 | break; | |
420a0d19 | 5407 | |
2ea97746 CE |
5408 | if ((rc = acl_check(ACL_WHERE_VRFY, address, acl_smtp_vrfy, |
5409 | &user_msg, &log_msg)) != OK) | |
5410 | done = smtp_handle_acl_fail(ACL_WHERE_VRFY, rc, user_msg, log_msg); | |
5411 | else | |
5412 | { | |
5413 | uschar * s = NULL; | |
5414 | address_item * addr = deliver_make_addr(address, FALSE); | |
5415 | ||
5416 | switch(verify_address(addr, NULL, vopt_is_recipient | vopt_qualify, -1, | |
5417 | -1, -1, NULL, NULL, NULL)) | |
5418 | { | |
5419 | case OK: | |
5420 | s = string_sprintf("250 <%s> is deliverable", address); | |
5421 | break; | |
420a0d19 | 5422 | |
2ea97746 CE |
5423 | case DEFER: |
5424 | s = (addr->user_message != NULL)? | |
5425 | string_sprintf("451 <%s> %s", address, addr->user_message) : | |
5426 | string_sprintf("451 Cannot resolve <%s> at this time", address); | |
5427 | break; | |
420a0d19 | 5428 | |
2ea97746 CE |
5429 | case FAIL: |
5430 | s = (addr->user_message != NULL)? | |
5431 | string_sprintf("550 <%s> %s", address, addr->user_message) : | |
5432 | string_sprintf("550 <%s> is not deliverable", address); | |
5433 | log_write(0, LOG_MAIN, "VRFY failed for %s %s", | |
5434 | smtp_cmd_argument, host_and_ident(TRUE)); | |
5435 | break; | |
5436 | } | |
5437 | ||
5438 | smtp_printf("%s\r\n", FALSE, s); | |
5439 | } | |
5440 | break; | |
420a0d19 CE |
5441 | } |
5442 | ||
420a0d19 | 5443 | |
2ea97746 CE |
5444 | case EXPN_CMD: |
5445 | HAD(SCH_EXPN); | |
5446 | rc = acl_check(ACL_WHERE_EXPN, NULL, acl_smtp_expn, &user_msg, &log_msg); | |
5447 | if (rc != OK) | |
5448 | done = smtp_handle_acl_fail(ACL_WHERE_EXPN, rc, user_msg, log_msg); | |
5449 | else | |
5450 | { | |
5451 | BOOL save_log_testing_mode = f.log_testing_mode; | |
5452 | f.address_test_mode = f.log_testing_mode = TRUE; | |
5453 | (void) verify_address(deliver_make_addr(smtp_cmd_data, FALSE), | |
5454 | smtp_out, vopt_is_recipient | vopt_qualify | vopt_expn, -1, -1, -1, | |
5455 | NULL, NULL, NULL); | |
5456 | f.address_test_mode = FALSE; | |
5457 | f.log_testing_mode = save_log_testing_mode; /* true for -bh */ | |
5458 | } | |
5459 | break; | |
420a0d19 | 5460 | |
420a0d19 | 5461 | |
2ea97746 | 5462 | #ifdef SUPPORT_TLS |
420a0d19 | 5463 | |
2ea97746 CE |
5464 | case STARTTLS_CMD: |
5465 | HAD(SCH_STARTTLS); | |
5466 | if (!fl.tls_advertised) | |
5467 | { | |
5468 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5469 | US"STARTTLS command used when not advertised"); | |
5470 | break; | |
5471 | } | |
420a0d19 | 5472 | |
2ea97746 | 5473 | /* Apply an ACL check if one is defined */ |
420a0d19 | 5474 | |
2ea97746 CE |
5475 | if ( acl_smtp_starttls |
5476 | && (rc = acl_check(ACL_WHERE_STARTTLS, NULL, acl_smtp_starttls, | |
5477 | &user_msg, &log_msg)) != OK | |
5478 | ) | |
5479 | { | |
5480 | done = smtp_handle_acl_fail(ACL_WHERE_STARTTLS, rc, user_msg, log_msg); | |
5481 | break; | |
5482 | } | |
420a0d19 | 5483 | |
2ea97746 CE |
5484 | /* RFC 2487 is not clear on when this command may be sent, though it |
5485 | does state that all information previously obtained from the client | |
5486 | must be discarded if a TLS session is started. It seems reasonable to | |
5487 | do an implied RSET when STARTTLS is received. */ | |
5488 | ||
5489 | incomplete_transaction_log(US"STARTTLS"); | |
5490 | cancel_cutthrough_connection(TRUE, US"STARTTLS received"); | |
5491 | smtp_reset(reset_point); | |
5492 | toomany = FALSE; | |
5493 | cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = FALSE; | |
5494 | ||
5495 | /* There's an attack where more data is read in past the STARTTLS command | |
5496 | before TLS is negotiated, then assumed to be part of the secure session | |
5497 | when used afterwards; we use segregated input buffers, so are not | |
5498 | vulnerable, but we want to note when it happens and, for sheer paranoia, | |
5499 | ensure that the buffer is "wiped". | |
5500 | Pipelining sync checks will normally have protected us too, unless disabled | |
5501 | by configuration. */ | |
5502 | ||
5503 | if (receive_smtp_buffered()) | |
5504 | { | |
5505 | DEBUG(D_any) | |
5506 | debug_printf("Non-empty input buffer after STARTTLS; naive attack?\n"); | |
5507 | if (tls_in.active.sock < 0) | |
5508 | smtp_inend = smtp_inptr = smtp_inbuffer; | |
5509 | /* and if TLS is already active, tls_server_start() should fail */ | |
5510 | } | |
420a0d19 | 5511 | |
2ea97746 CE |
5512 | /* There is nothing we value in the input buffer and if TLS is successfully |
5513 | negotiated, we won't use this buffer again; if TLS fails, we'll just read | |
5514 | fresh content into it. The buffer contains arbitrary content from an | |
5515 | untrusted remote source; eg: NOOP <shellcode>\r\nSTARTTLS\r\n | |
5516 | It seems safest to just wipe away the content rather than leave it as a | |
5517 | target to jump to. */ | |
5518 | ||
5519 | memset(smtp_inbuffer, 0, IN_BUFFER_SIZE); | |
5520 | ||
5521 | /* Attempt to start up a TLS session, and if successful, discard all | |
5522 | knowledge that was obtained previously. At least, that's what the RFC says, | |
5523 | and that's what happens by default. However, in order to work round YAEB, | |
5524 | there is an option to remember the esmtp state. Sigh. | |
5525 | ||
5526 | We must allow for an extra EHLO command and an extra AUTH command after | |
5527 | STARTTLS that don't add to the nonmail command count. */ | |
5528 | ||
5529 | s = NULL; | |
5530 | if ((rc = tls_server_start(tls_require_ciphers, &s)) == OK) | |
5531 | { | |
5532 | if (!tls_remember_esmtp) | |
5533 | fl.helo_seen = fl.esmtp = fl.auth_advertised = f.smtp_in_pipelining_advertised = FALSE; | |
5534 | cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE; | |
5535 | cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE; | |
5536 | cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE; | |
5537 | if (sender_helo_name) | |
5538 | { | |
5539 | store_free(sender_helo_name); | |
5540 | sender_helo_name = NULL; | |
5541 | host_build_sender_fullhost(); /* Rebuild */ | |
5542 | set_process_info("handling incoming TLS connection from %s", | |
5543 | host_and_ident(FALSE)); | |
5544 | } | |
5545 | received_protocol = | |
5546 | (sender_host_address ? protocols : protocols_local) | |
5547 | [ (fl.esmtp | |
5548 | ? pextend + (sender_host_authenticated ? pauthed : 0) | |
5549 | : pnormal) | |
5550 | + (tls_in.active.sock >= 0 ? pcrpted : 0) | |
5551 | ]; | |
5552 | ||
5553 | sender_host_auth_pubname = sender_host_authenticated = NULL; | |
5554 | authenticated_id = NULL; | |
5555 | sync_cmd_limit = NON_SYNC_CMD_NON_PIPELINING; | |
5556 | DEBUG(D_tls) debug_printf("TLS active\n"); | |
5557 | break; /* Successful STARTTLS */ | |
5558 | } | |
5559 | else | |
5560 | (void) smtp_log_tls_fail(s); | |
420a0d19 | 5561 | |
2ea97746 CE |
5562 | /* Some local configuration problem was discovered before actually trying |
5563 | to do a TLS handshake; give a temporary error. */ | |
420a0d19 | 5564 | |
2ea97746 CE |
5565 | if (rc == DEFER) |
5566 | { | |
5567 | smtp_printf("454 TLS currently unavailable\r\n", FALSE); | |
5568 | break; | |
5569 | } | |
420a0d19 | 5570 | |
2ea97746 CE |
5571 | /* Hard failure. Reject everything except QUIT or closed connection. One |
5572 | cause for failure is a nested STARTTLS, in which case tls_in.active remains | |
5573 | set, but we must still reject all incoming commands. Another is a handshake | |
5574 | failure - and there may some encrypted data still in the pipe to us, which we | |
5575 | see as garbage commands. */ | |
5576 | ||
5577 | DEBUG(D_tls) debug_printf("TLS failed to start\n"); | |
5578 | while (done <= 0) switch(smtp_read_command(FALSE, GETC_BUFFER_UNLIMITED)) | |
5579 | { | |
5580 | case EOF_CMD: | |
5581 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by EOF", | |
5582 | smtp_get_connection_info()); | |
5583 | smtp_notquit_exit(US"tls-failed", NULL, NULL); | |
5584 | done = 2; | |
5585 | break; | |
5586 | ||
5587 | /* It is perhaps arguable as to which exit ACL should be called here, | |
5588 | but as it is probably a situation that almost never arises, it | |
5589 | probably doesn't matter. We choose to call the real QUIT ACL, which in | |
5590 | some sense is perhaps "right". */ | |
5591 | ||
5592 | case QUIT_CMD: | |
5593 | user_msg = NULL; | |
5594 | if ( acl_smtp_quit | |
5595 | && ((rc = acl_check(ACL_WHERE_QUIT, NULL, acl_smtp_quit, &user_msg, | |
5596 | &log_msg)) == ERROR)) | |
5597 | log_write(0, LOG_MAIN|LOG_PANIC, "ACL for QUIT returned ERROR: %s", | |
5598 | log_msg); | |
5599 | if (user_msg) | |
5600 | smtp_respond(US"221", 3, TRUE, user_msg); | |
5601 | else | |
5602 | smtp_printf("221 %s closing connection\r\n", FALSE, smtp_active_hostname); | |
5603 | log_write(L_smtp_connection, LOG_MAIN, "%s closed by QUIT", | |
5604 | smtp_get_connection_info()); | |
5605 | done = 2; | |
5606 | break; | |
5607 | ||
5608 | default: | |
5609 | smtp_printf("554 Security failure\r\n", FALSE); | |
5610 | break; | |
5611 | } | |
5612 | tls_close(NULL, TLS_SHUTDOWN_NOWAIT); | |
5613 | break; | |
420a0d19 CE |
5614 | #endif |
5615 | ||
5616 | ||
5617 | /* The ACL for QUIT is provided for gathering statistical information or | |
5618 | similar; it does not affect the response code, but it can supply a custom | |
5619 | message. */ | |
5620 | ||
5621 | case QUIT_CMD: | |
2ea97746 CE |
5622 | smtp_quit_handler(&user_msg, &log_msg); |
5623 | done = 2; | |
5624 | break; | |
420a0d19 CE |
5625 | |
5626 | ||
5627 | case RSET_CMD: | |
2ea97746 CE |
5628 | smtp_rset_handler(); |
5629 | cancel_cutthrough_connection(TRUE, US"RSET received"); | |
5630 | smtp_reset(reset_point); | |
5631 | toomany = FALSE; | |
5632 | break; | |
420a0d19 CE |
5633 | |
5634 | ||
5635 | case NOOP_CMD: | |
2ea97746 CE |
5636 | HAD(SCH_NOOP); |
5637 | smtp_printf("250 OK\r\n", FALSE); | |
5638 | break; | |
420a0d19 CE |
5639 | |
5640 | ||
5641 | /* Show ETRN/EXPN/VRFY if there's an ACL for checking hosts; if actually | |
5642 | used, a check will be done for permitted hosts. Show STARTTLS only if not | |
5643 | already in a TLS session and if it would be advertised in the EHLO | |
5644 | response. */ | |
5645 | ||
5646 | case HELP_CMD: | |
2ea97746 CE |
5647 | HAD(SCH_HELP); |
5648 | smtp_printf("214-Commands supported:\r\n", TRUE); | |
5649 | { | |
5650 | uschar buffer[256]; | |
5651 | buffer[0] = 0; | |
5652 | Ustrcat(buffer, " AUTH"); | |
5653 | #ifdef SUPPORT_TLS | |
5654 | if (tls_in.active.sock < 0 && | |
5655 | verify_check_host(&tls_advertise_hosts) != FAIL) | |
5656 | Ustrcat(buffer, " STARTTLS"); | |
5657 | #endif | |
5658 | Ustrcat(buffer, " HELO EHLO MAIL RCPT DATA BDAT"); | |
5659 | Ustrcat(buffer, " NOOP QUIT RSET HELP"); | |
5660 | if (acl_smtp_etrn != NULL) Ustrcat(buffer, " ETRN"); | |
5661 | if (acl_smtp_expn != NULL) Ustrcat(buffer, " EXPN"); | |
5662 | if (acl_smtp_vrfy != NULL) Ustrcat(buffer, " VRFY"); | |
5663 | smtp_printf("214%s\r\n", FALSE, buffer); | |
5664 | } | |
5665 | break; | |
420a0d19 CE |
5666 | |
5667 | ||
5668 | case EOF_CMD: | |
2ea97746 CE |
5669 | incomplete_transaction_log(US"connection lost"); |
5670 | smtp_notquit_exit(US"connection-lost", US"421", | |
5671 | US"%s lost input connection", smtp_active_hostname); | |
5672 | ||
5673 | /* Don't log by default unless in the middle of a message, as some mailers | |
5674 | just drop the call rather than sending QUIT, and it clutters up the logs. | |
5675 | */ | |
5676 | ||
5677 | if (sender_address || recipients_count > 0) | |
5678 | log_write(L_lost_incoming_connection, LOG_MAIN, | |
5679 | "unexpected %s while reading SMTP command from %s%s%s D=%s", | |
5680 | f.sender_host_unknown ? "EOF" : "disconnection", | |
5681 | f.tcp_in_fastopen_logged | |
5682 | ? US"" | |
5683 | : f.tcp_in_fastopen | |
5684 | ? f.tcp_in_fastopen_data ? US"TFO* " : US"TFO " | |
5685 | : US"", | |
5686 | host_and_ident(FALSE), smtp_read_error, | |
5687 | string_timesince(&smtp_connection_start) | |
5688 | ); | |
420a0d19 | 5689 | |
2ea97746 CE |
5690 | else |
5691 | log_write(L_smtp_connection, LOG_MAIN, "%s %slost%s D=%s", | |
5692 | smtp_get_connection_info(), | |
5693 | f.tcp_in_fastopen && !f.tcp_in_fastopen_logged ? US"TFO " : US"", | |
5694 | smtp_read_error, | |
5695 | string_timesince(&smtp_connection_start) | |
5696 | ); | |
5697 | ||
5698 | done = 1; | |
420a0d19 | 5699 | break; |
420a0d19 | 5700 | |
420a0d19 | 5701 | |
2ea97746 CE |
5702 | case ETRN_CMD: |
5703 | HAD(SCH_ETRN); | |
5704 | if (sender_address) | |
5705 | { | |
5706 | done = synprot_error(L_smtp_protocol_error, 503, NULL, | |
5707 | US"ETRN is not permitted inside a transaction"); | |
5708 | break; | |
5709 | } | |
420a0d19 | 5710 | |
2ea97746 CE |
5711 | log_write(L_etrn, LOG_MAIN, "ETRN %s received from %s", smtp_cmd_argument, |
5712 | host_and_ident(FALSE)); | |
420a0d19 | 5713 | |
2ea97746 CE |
5714 | if ((rc = acl_check(ACL_WHERE_ETRN, NULL, acl_smtp_etrn, |
5715 | &user_msg, &log_msg)) != OK) | |
5716 | { | |
5717 | done = smtp_handle_acl_fail(ACL_WHERE_ETRN, rc, user_msg, log_msg); | |
5718 | break; | |
5719 | } | |
420a0d19 | 5720 | |
2ea97746 CE |
5721 | /* Compute the serialization key for this command. */ |
5722 | ||
5723 | etrn_serialize_key = string_sprintf("etrn-%s\n", smtp_cmd_data); | |
5724 | ||
5725 | /* If a command has been specified for running as a result of ETRN, we | |
5726 | permit any argument to ETRN. If not, only the # standard form is permitted, | |
5727 | since that is strictly the only kind of ETRN that can be implemented | |
5728 | according to the RFC. */ | |
5729 | ||
5730 | if (smtp_etrn_command) | |
5731 | { | |
5732 | uschar *error; | |
5733 | BOOL rc; | |
5734 | etrn_command = smtp_etrn_command; | |
5735 | deliver_domain = smtp_cmd_data; | |
5736 | rc = transport_set_up_command(&argv, smtp_etrn_command, TRUE, 0, NULL, | |
5737 | US"ETRN processing", &error); | |
5738 | deliver_domain = NULL; | |
5739 | if (!rc) | |
5740 | { | |
5741 | log_write(0, LOG_MAIN|LOG_PANIC, "failed to set up ETRN command: %s", | |
5742 | error); | |
5743 | smtp_printf("458 Internal failure\r\n", FALSE); | |
5744 | break; | |
5745 | } | |
5746 | } | |
420a0d19 | 5747 | |
2ea97746 | 5748 | /* Else set up to call Exim with the -R option. */ |
420a0d19 | 5749 | |
2ea97746 CE |
5750 | else |
5751 | { | |
5752 | if (*smtp_cmd_data++ != '#') | |
5753 | { | |
5754 | done = synprot_error(L_smtp_syntax_error, 501, NULL, | |
5755 | US"argument must begin with #"); | |
5756 | break; | |
5757 | } | |
5758 | etrn_command = US"exim -R"; | |
5759 | argv = CUSS child_exec_exim(CEE_RETURN_ARGV, TRUE, NULL, TRUE, | |
5760 | *queue_name ? 4 : 2, | |
5761 | US"-R", smtp_cmd_data, | |
5762 | US"-MCG", queue_name); | |
5763 | } | |
420a0d19 | 5764 | |
2ea97746 CE |
5765 | /* If we are host-testing, don't actually do anything. */ |
5766 | ||
5767 | if (host_checking) | |
5768 | { | |
5769 | HDEBUG(D_any) | |
5770 | { | |
5771 | debug_printf("ETRN command is: %s\n", etrn_command); | |
5772 | debug_printf("ETRN command execution skipped\n"); | |
5773 | } | |
5774 | if (user_msg == NULL) smtp_printf("250 OK\r\n", FALSE); | |
5775 | else smtp_user_msg(US"250", user_msg); | |
5776 | break; | |
5777 | } | |
420a0d19 | 5778 | |
420a0d19 | 5779 | |
2ea97746 CE |
5780 | /* If ETRN queue runs are to be serialized, check the database to |
5781 | ensure one isn't already running. */ | |
420a0d19 | 5782 | |
2ea97746 CE |
5783 | if (smtp_etrn_serialize && !enq_start(etrn_serialize_key, 1)) |
5784 | { | |
5785 | smtp_printf("458 Already processing %s\r\n", FALSE, smtp_cmd_data); | |
5786 | break; | |
5787 | } | |
420a0d19 | 5788 | |
2ea97746 CE |
5789 | /* Fork a child process and run the command. We don't want to have to |
5790 | wait for the process at any point, so set SIGCHLD to SIG_IGN before | |
5791 | forking. It should be set that way anyway for external incoming SMTP, | |
5792 | but we save and restore to be tidy. If serialization is required, we | |
5793 | actually run the command in yet another process, so we can wait for it | |
5794 | to complete and then remove the serialization lock. */ | |
5795 | ||
5796 | oldsignal = signal(SIGCHLD, SIG_IGN); | |
5797 | ||
5798 | if ((pid = fork()) == 0) | |
5799 | { | |
5800 | smtp_input = FALSE; /* This process is not associated with the */ | |
5801 | (void)fclose(smtp_in); /* SMTP call any more. */ | |
5802 | (void)fclose(smtp_out); | |
5803 | ||
5804 | signal(SIGCHLD, SIG_DFL); /* Want to catch child */ | |
5805 | ||
5806 | /* If not serializing, do the exec right away. Otherwise, fork down | |
5807 | into another process. */ | |
5808 | ||
5809 | if (!smtp_etrn_serialize || (pid = fork()) == 0) | |
5810 | { | |
5811 | DEBUG(D_exec) debug_print_argv(argv); | |
5812 | exim_nullstd(); /* Ensure std{in,out,err} exist */ | |
5813 | execv(CS argv[0], (char *const *)argv); | |
5814 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "exec of \"%s\" (ETRN) failed: %s", | |
5815 | etrn_command, strerror(errno)); | |
5816 | _exit(EXIT_FAILURE); /* paranoia */ | |
5817 | } | |
5818 | ||
5819 | /* Obey this if smtp_serialize and the 2nd fork yielded non-zero. That | |
5820 | is, we are in the first subprocess, after forking again. All we can do | |
5821 | for a failing fork is to log it. Otherwise, wait for the 2nd process to | |
5822 | complete, before removing the serialization. */ | |
5823 | ||
5824 | if (pid < 0) | |
5825 | log_write(0, LOG_MAIN|LOG_PANIC, "2nd fork for serialized ETRN " | |
5826 | "failed: %s", strerror(errno)); | |
5827 | else | |
5828 | { | |
5829 | int status; | |
5830 | DEBUG(D_any) debug_printf("waiting for serialized ETRN process %d\n", | |
5831 | (int)pid); | |
5832 | (void)wait(&status); | |
5833 | DEBUG(D_any) debug_printf("serialized ETRN process %d ended\n", | |
5834 | (int)pid); | |
5835 | } | |
5836 | ||
5837 | enq_end(etrn_serialize_key); | |
5838 | _exit(EXIT_SUCCESS); | |
5839 | } | |
420a0d19 | 5840 | |
2ea97746 CE |
5841 | /* Back in the top level SMTP process. Check that we started a subprocess |
5842 | and restore the signal state. */ | |
420a0d19 CE |
5843 | |
5844 | if (pid < 0) | |
2ea97746 CE |
5845 | { |
5846 | log_write(0, LOG_MAIN|LOG_PANIC, "fork of process for ETRN failed: %s", | |
5847 | strerror(errno)); | |
5848 | smtp_printf("458 Unable to fork process\r\n", FALSE); | |
5849 | if (smtp_etrn_serialize) enq_end(etrn_serialize_key); | |
5850 | } | |
420a0d19 | 5851 | else |
2ea97746 CE |
5852 | { |
5853 | if (user_msg == NULL) smtp_printf("250 OK\r\n", FALSE); | |
5854 | else smtp_user_msg(US"250", user_msg); | |
5855 | } | |
420a0d19 | 5856 | |
2ea97746 CE |
5857 | signal(SIGCHLD, oldsignal); |
5858 | break; | |
420a0d19 CE |
5859 | |
5860 | ||
5861 | case BADARG_CMD: | |
2ea97746 CE |
5862 | done = synprot_error(L_smtp_syntax_error, 501, NULL, |
5863 | US"unexpected argument data"); | |
5864 | break; | |
420a0d19 CE |
5865 | |
5866 | ||
5867 | /* This currently happens only for NULLs, but could be extended. */ | |
5868 | ||
5869 | case BADCHAR_CMD: | |
2ea97746 CE |
5870 | done = synprot_error(L_smtp_syntax_error, 0, NULL, /* Just logs */ |
5871 | US"NUL character(s) present (shown as '?')"); | |
5872 | smtp_printf("501 NUL characters are not allowed in SMTP commands\r\n", | |
5873 | FALSE); | |
5874 | break; | |
420a0d19 CE |
5875 | |
5876 | ||
5877 | case BADSYN_CMD: | |
5878 | SYNC_FAILURE: | |
2ea97746 CE |
5879 | if (smtp_inend >= smtp_inbuffer + IN_BUFFER_SIZE) |
5880 | smtp_inend = smtp_inbuffer + IN_BUFFER_SIZE - 1; | |
5881 | c = smtp_inend - smtp_inptr; | |
5882 | if (c > 150) c = 150; /* limit logged amount */ | |
5883 | smtp_inptr[c] = 0; | |
5884 | incomplete_transaction_log(US"sync failure"); | |
5885 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP protocol synchronization error " | |
5886 | "(next input sent too soon: pipelining was%s advertised): " | |
5887 | "rejected \"%s\" %s next input=\"%s\"", | |
5888 | f.smtp_in_pipelining_advertised ? "" : " not", | |
5889 | smtp_cmd_buffer, host_and_ident(TRUE), | |
5890 | string_printing(smtp_inptr)); | |
5891 | smtp_notquit_exit(US"synchronization-error", US"554", | |
5892 | US"SMTP synchronization error"); | |
5893 | done = 1; /* Pretend eof - drops connection */ | |
5894 | break; | |
420a0d19 CE |
5895 | |
5896 | ||
5897 | case TOO_MANY_NONMAIL_CMD: | |
2ea97746 CE |
5898 | s = smtp_cmd_buffer; |
5899 | while (*s != 0 && !isspace(*s)) s++; | |
5900 | incomplete_transaction_log(US"too many non-mail commands"); | |
5901 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5902 | "nonmail commands (last was \"%.*s\")", host_and_ident(FALSE), | |
5903 | (int)(s - smtp_cmd_buffer), smtp_cmd_buffer); | |
5904 | smtp_notquit_exit(US"bad-commands", US"554", US"Too many nonmail commands"); | |
5905 | done = 1; /* Pretend eof - drops connection */ | |
5906 | break; | |
420a0d19 | 5907 | |
2ea97746 | 5908 | #ifdef SUPPORT_PROXY |
420a0d19 | 5909 | case PROXY_FAIL_IGNORE_CMD: |
2ea97746 CE |
5910 | smtp_printf("503 Command refused, required Proxy negotiation failed\r\n", FALSE); |
5911 | break; | |
5912 | #endif | |
420a0d19 CE |
5913 | |
5914 | default: | |
2ea97746 CE |
5915 | if (unknown_command_count++ >= smtp_max_unknown_commands) |
5916 | { | |
5917 | log_write(L_smtp_syntax_error, LOG_MAIN, | |
5918 | "SMTP syntax error in \"%s\" %s %s", | |
5919 | string_printing(smtp_cmd_buffer), host_and_ident(TRUE), | |
5920 | US"unrecognized command"); | |
5921 | incomplete_transaction_log(US"unrecognized command"); | |
5922 | smtp_notquit_exit(US"bad-commands", US"500", | |
5923 | US"Too many unrecognized commands"); | |
5924 | done = 2; | |
5925 | log_write(0, LOG_MAIN|LOG_REJECT, "SMTP call from %s dropped: too many " | |
5926 | "unrecognized commands (last was \"%s\")", host_and_ident(FALSE), | |
5927 | string_printing(smtp_cmd_buffer)); | |
5928 | } | |
5929 | else | |
5930 | done = synprot_error(L_smtp_syntax_error, 500, NULL, | |
5931 | US"unrecognized command"); | |
5932 | break; | |
420a0d19 CE |
5933 | } |
5934 | ||
5935 | /* This label is used by goto's inside loops that want to break out to | |
5936 | the end of the command-processing loop. */ | |
5937 | ||
5938 | COMMAND_LOOP: | |
5939 | last_was_rej_mail = was_rej_mail; /* Remember some last commands for */ | |
5940 | last_was_rcpt = was_rcpt; /* protocol error handling */ | |
5941 | continue; | |
5942 | } | |
5943 | ||
5944 | return done - 2; /* Convert yield values */ | |
5945 | } | |
5946 | ||
2ea97746 CE |
5947 | |
5948 | ||
5949 | gstring * | |
5950 | authres_smtpauth(gstring * g) | |
5951 | { | |
5952 | if (!sender_host_authenticated) | |
5953 | return g; | |
5954 | ||
5955 | g = string_append(g, 2, US";\n\tauth=pass (", sender_host_auth_pubname); | |
5956 | ||
5957 | if (Ustrcmp(sender_host_auth_pubname, "tls") != 0) | |
5958 | g = string_append(g, 2, US") smtp.auth=", authenticated_id); | |
5959 | else if (authenticated_id) | |
5960 | g = string_append(g, 2, US") x509.auth=", authenticated_id); | |
5961 | else | |
5962 | g = string_catn(g, US") reason=x509.auth", 17); | |
5963 | ||
5964 | if (authenticated_sender) | |
5965 | g = string_append(g, 2, US" smtp.mailfrom=", authenticated_sender); | |
5966 | return g; | |
5967 | } | |
5968 | ||
5969 | ||
5970 | ||
420a0d19 CE |
5971 | /* vi: aw ai sw=2 |
5972 | */ | |
5973 | /* End of smtp_in.c */ |