Commit | Line | Data |
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420a0d19 CE |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
5 | /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2003-???? */ | |
6 | /* License: GPL */ | |
7 | ||
8 | /* Code for calling spamassassin's spamd. Called from acl.c. */ | |
9 | ||
10 | #include "exim.h" | |
11 | #ifdef WITH_CONTENT_SCAN | |
12 | #include "spam.h" | |
13 | ||
14 | uschar spam_score_buffer[16]; | |
15 | uschar spam_score_int_buffer[16]; | |
16 | uschar spam_bar_buffer[128]; | |
17 | uschar spam_report_buffer[32600]; | |
18 | uschar prev_user_name[128] = ""; | |
19 | int spam_ok = 0; | |
20 | int spam_rc = 0; | |
21 | uschar *prev_spamd_address_work = NULL; | |
22 | ||
23 | int | |
24 | spam(uschar **listptr) | |
25 | { | |
26 | int sep = 0; | |
27 | uschar *list = *listptr; | |
28 | uschar *user_name; | |
29 | uschar user_name_buffer[128]; | |
30 | unsigned long mbox_size; | |
31 | FILE *mbox_file; | |
32 | int spamd_sock = -1; | |
33 | uschar spamd_buffer[32600]; | |
34 | int i, j, offset, result; | |
35 | uschar spamd_version[8]; | |
36 | uschar spamd_score_char; | |
37 | double spamd_threshold, spamd_score; | |
38 | int spamd_report_offset; | |
39 | uschar *p,*q; | |
40 | int override = 0; | |
41 | time_t start; | |
42 | size_t read, wrote; | |
43 | struct sockaddr_un server; | |
44 | #ifndef NO_POLL_H | |
45 | struct pollfd pollfd; | |
46 | #else /* Patch posted by Erik ? for OS X */ | |
47 | struct timeval select_tv; /* and applied by PH */ | |
48 | fd_set select_fd; | |
49 | #endif | |
50 | uschar *spamd_address_work; | |
51 | ||
52 | /* stop compiler warning */ | |
53 | result = 0; | |
54 | ||
55 | /* find the username from the option list */ | |
56 | if ((user_name = string_nextinlist(&list, &sep, | |
57 | user_name_buffer, | |
58 | sizeof(user_name_buffer))) == NULL) { | |
59 | /* no username given, this means no scanning should be done */ | |
60 | return FAIL; | |
61 | }; | |
62 | ||
63 | /* if username is "0" or "false", do not scan */ | |
64 | if ( (Ustrcmp(user_name,"0") == 0) || | |
65 | (strcmpic(user_name,US"false") == 0) ) { | |
66 | return FAIL; | |
67 | }; | |
68 | ||
69 | /* if there is an additional option, check if it is "true" */ | |
70 | if (strcmpic(list,US"true") == 0) { | |
71 | /* in that case, always return true later */ | |
72 | override = 1; | |
73 | }; | |
74 | ||
75 | /* expand spamd_address if needed */ | |
76 | if (*spamd_address == '$') { | |
77 | spamd_address_work = expand_string(spamd_address); | |
78 | if (spamd_address_work == NULL) { | |
79 | log_write(0, LOG_MAIN|LOG_PANIC, | |
80 | "spamassassin acl condition: spamd_address starts with $, but expansion failed: %s", expand_string_message); | |
81 | return DEFER; | |
82 | } | |
83 | } | |
84 | else | |
85 | spamd_address_work = spamd_address; | |
86 | ||
87 | /* check if previous spamd_address was expanded and has changed. dump cached results if so */ | |
88 | if ( spam_ok && ( prev_spamd_address_work != NULL) && (Ustrcmp(prev_spamd_address_work, spamd_address_work) != 0)) { | |
89 | spam_ok = 0; | |
90 | } | |
91 | ||
92 | /* if we scanned for this username last time, just return */ | |
93 | if ( spam_ok && ( Ustrcmp(prev_user_name, user_name) == 0 ) ) { | |
94 | if (override) | |
95 | return OK; | |
96 | else | |
97 | return spam_rc; | |
98 | }; | |
99 | ||
100 | /* make sure the eml mbox file is spooled up */ | |
101 | mbox_file = spool_mbox(&mbox_size, NULL); | |
102 | ||
103 | if (mbox_file == NULL) { | |
104 | /* error while spooling */ | |
105 | log_write(0, LOG_MAIN|LOG_PANIC, | |
106 | "spam acl condition: error while creating mbox spool file"); | |
107 | return DEFER; | |
108 | }; | |
109 | ||
110 | start = time(NULL); | |
111 | ||
112 | /* socket does not start with '/' -> network socket */ | |
113 | if (*spamd_address_work != '/') { | |
114 | int num_servers = 0; | |
115 | int current_server; | |
116 | uschar *address = NULL; | |
117 | uschar *spamd_address_list_ptr = spamd_address_work; | |
118 | uschar address_buffer[256]; | |
119 | spamd_address_container * spamd_address_vector[32]; | |
120 | ||
121 | /* Check how many spamd servers we have | |
122 | and register their addresses */ | |
123 | while ((address = string_nextinlist(&spamd_address_list_ptr, &sep, | |
124 | address_buffer, | |
125 | sizeof(address_buffer))) != NULL) { | |
126 | ||
127 | /* Potential memory leak as we never free the store. */ | |
128 | spamd_address_container *this_spamd = | |
129 | (spamd_address_container *)store_get(sizeof(spamd_address_container)); | |
130 | ||
131 | /* grok spamd address and port */ | |
132 | if( sscanf(CS address, "%s %u", this_spamd->tcp_addr, &(this_spamd->tcp_port)) != 2 ) { | |
133 | log_write(0, LOG_MAIN, | |
134 | "spam acl condition: warning - invalid spamd address: '%s'", address); | |
135 | continue; | |
136 | }; | |
137 | ||
138 | spamd_address_vector[num_servers] = this_spamd; | |
139 | num_servers++; | |
140 | if (num_servers > 31) | |
141 | break; | |
142 | }; | |
143 | ||
144 | /* check if we have at least one server */ | |
145 | if (!num_servers) { | |
146 | log_write(0, LOG_MAIN|LOG_PANIC, | |
147 | "spam acl condition: no useable spamd server addresses in spamd_address configuration option."); | |
148 | (void)fclose(mbox_file); | |
149 | return DEFER; | |
150 | }; | |
151 | ||
152 | while ( num_servers > 0 ) { | |
153 | int i; | |
154 | ||
155 | /* Randomly pick a server to try */ | |
156 | current_server = random_number( num_servers ); | |
157 | ||
158 | debug_printf("trying server %s, port %u\n", | |
159 | spamd_address_vector[current_server]->tcp_addr, | |
160 | spamd_address_vector[current_server]->tcp_port); | |
161 | ||
162 | /* contact a spamd */ | |
163 | if ( (spamd_sock = ip_socket(SOCK_STREAM, AF_INET)) < 0) { | |
164 | log_write(0, LOG_MAIN|LOG_PANIC, | |
165 | "spam acl condition: error creating IP socket for spamd"); | |
166 | (void)fclose(mbox_file); | |
167 | return DEFER; | |
168 | }; | |
169 | ||
170 | if (ip_connect( spamd_sock, | |
171 | AF_INET, | |
172 | spamd_address_vector[current_server]->tcp_addr, | |
173 | spamd_address_vector[current_server]->tcp_port, | |
174 | 5 ) > -1) { | |
175 | /* connection OK */ | |
176 | break; | |
177 | }; | |
178 | ||
179 | log_write(0, LOG_MAIN|LOG_PANIC, | |
180 | "spam acl condition: warning - spamd connection to %s, port %u failed: %s", | |
181 | spamd_address_vector[current_server]->tcp_addr, | |
182 | spamd_address_vector[current_server]->tcp_port, | |
183 | strerror(errno)); | |
184 | ||
185 | (void)close(spamd_sock); | |
186 | ||
187 | /* Remove the server from the list. XXX We should free the memory */ | |
188 | num_servers--; | |
189 | for( i = current_server; i < num_servers; i++ ) | |
190 | spamd_address_vector[i] = spamd_address_vector[i+1]; | |
191 | } | |
192 | ||
193 | if ( num_servers == 0 ) { | |
194 | log_write(0, LOG_MAIN|LOG_PANIC, "spam acl condition: all spamd servers failed"); | |
195 | (void)fclose(mbox_file); | |
196 | return DEFER; | |
197 | } | |
198 | ||
199 | } | |
200 | else { | |
201 | /* open the local socket */ | |
202 | ||
203 | if ((spamd_sock = socket(AF_UNIX, SOCK_STREAM, 0)) < 0) { | |
204 | log_write(0, LOG_MAIN|LOG_PANIC, | |
205 | "malware acl condition: spamd: unable to acquire socket (%s)", | |
206 | strerror(errno)); | |
207 | (void)fclose(mbox_file); | |
208 | return DEFER; | |
209 | } | |
210 | ||
211 | server.sun_family = AF_UNIX; | |
212 | Ustrcpy(server.sun_path, spamd_address_work); | |
213 | ||
214 | if (connect(spamd_sock, (struct sockaddr *) &server, sizeof(struct sockaddr_un)) < 0) { | |
215 | log_write(0, LOG_MAIN|LOG_PANIC, | |
216 | "malware acl condition: spamd: unable to connect to UNIX socket %s (%s)", | |
217 | spamd_address_work, strerror(errno) ); | |
218 | (void)fclose(mbox_file); | |
219 | (void)close(spamd_sock); | |
220 | return DEFER; | |
221 | } | |
222 | ||
223 | } | |
224 | ||
225 | if (spamd_sock == -1) { | |
226 | log_write(0, LOG_MAIN|LOG_PANIC, | |
227 | "programming fault, spamd_sock unexpectedly unset"); | |
228 | (void)fclose(mbox_file); | |
229 | (void)close(spamd_sock); | |
230 | return DEFER; | |
231 | } | |
232 | ||
233 | /* now we are connected to spamd on spamd_sock */ | |
234 | (void)string_format(spamd_buffer, | |
235 | sizeof(spamd_buffer), | |
236 | "REPORT SPAMC/1.2\r\nUser: %s\r\nContent-length: %ld\r\n\r\n", | |
237 | user_name, | |
238 | mbox_size); | |
239 | ||
240 | /* send our request */ | |
241 | if (send(spamd_sock, spamd_buffer, Ustrlen(spamd_buffer), 0) < 0) { | |
242 | (void)close(spamd_sock); | |
243 | log_write(0, LOG_MAIN|LOG_PANIC, | |
244 | "spam acl condition: spamd send failed: %s", strerror(errno)); | |
245 | (void)fclose(mbox_file); | |
246 | (void)close(spamd_sock); | |
247 | return DEFER; | |
248 | }; | |
249 | ||
250 | /* now send the file */ | |
251 | /* spamd sometimes accepts conections but doesn't read data off | |
252 | * the connection. We make the file descriptor non-blocking so | |
253 | * that the write will only write sufficient data without blocking | |
254 | * and we poll the desciptor to make sure that we can write without | |
255 | * blocking. Short writes are gracefully handled and if the whole | |
256 | * trasaction takes too long it is aborted. | |
257 | * Note: poll() is not supported in OSX 10.2 and is reported to be | |
258 | * broken in more recent versions (up to 10.4). | |
259 | */ | |
260 | #ifndef NO_POLL_H | |
261 | pollfd.fd = spamd_sock; | |
262 | pollfd.events = POLLOUT; | |
263 | #endif | |
264 | (void)fcntl(spamd_sock, F_SETFL, O_NONBLOCK); | |
265 | do { | |
266 | read = fread(spamd_buffer,1,sizeof(spamd_buffer),mbox_file); | |
267 | if (read > 0) { | |
268 | offset = 0; | |
269 | again: | |
270 | #ifndef NO_POLL_H | |
271 | result = poll(&pollfd, 1, 1000); | |
272 | ||
273 | /* Patch posted by Erik ? for OS X and applied by PH */ | |
274 | #else | |
275 | select_tv.tv_sec = 1; | |
276 | select_tv.tv_usec = 0; | |
277 | FD_ZERO(&select_fd); | |
278 | FD_SET(spamd_sock, &select_fd); | |
279 | result = select(spamd_sock+1, NULL, &select_fd, NULL, &select_tv); | |
280 | #endif | |
281 | /* End Erik's patch */ | |
282 | ||
283 | if (result == -1 && errno == EINTR) | |
284 | goto again; | |
285 | else if (result < 1) { | |
286 | if (result == -1) | |
287 | log_write(0, LOG_MAIN|LOG_PANIC, | |
288 | "spam acl condition: %s on spamd socket", strerror(errno)); | |
289 | else { | |
290 | if (time(NULL) - start < SPAMD_TIMEOUT) | |
291 | goto again; | |
292 | log_write(0, LOG_MAIN|LOG_PANIC, | |
293 | "spam acl condition: timed out writing spamd socket"); | |
294 | } | |
295 | (void)close(spamd_sock); | |
296 | (void)fclose(mbox_file); | |
297 | return DEFER; | |
298 | } | |
299 | ||
300 | wrote = send(spamd_sock,spamd_buffer + offset,read - offset,0); | |
301 | if (wrote == -1) | |
302 | { | |
303 | log_write(0, LOG_MAIN|LOG_PANIC, | |
304 | "spam acl condition: %s on spamd socket", strerror(errno)); | |
305 | (void)close(spamd_sock); | |
306 | (void)fclose(mbox_file); | |
307 | return DEFER; | |
308 | } | |
309 | if (offset + wrote != read) { | |
310 | offset += wrote; | |
311 | goto again; | |
312 | } | |
313 | } | |
314 | } | |
315 | while (!feof(mbox_file) && !ferror(mbox_file)); | |
316 | if (ferror(mbox_file)) { | |
317 | log_write(0, LOG_MAIN|LOG_PANIC, | |
318 | "spam acl condition: error reading spool file: %s", strerror(errno)); | |
319 | (void)close(spamd_sock); | |
320 | (void)fclose(mbox_file); | |
321 | return DEFER; | |
322 | } | |
323 | ||
324 | (void)fclose(mbox_file); | |
325 | ||
326 | /* we're done sending, close socket for writing */ | |
327 | shutdown(spamd_sock,SHUT_WR); | |
328 | ||
329 | /* read spamd response using what's left of the timeout. | |
330 | */ | |
331 | memset(spamd_buffer, 0, sizeof(spamd_buffer)); | |
332 | offset = 0; | |
333 | while((i = ip_recv(spamd_sock, | |
334 | spamd_buffer + offset, | |
335 | sizeof(spamd_buffer) - offset - 1, | |
336 | SPAMD_TIMEOUT - time(NULL) + start)) > 0 ) { | |
337 | offset += i; | |
338 | } | |
339 | ||
340 | /* error handling */ | |
341 | if((i <= 0) && (errno != 0)) { | |
342 | log_write(0, LOG_MAIN|LOG_PANIC, | |
343 | "spam acl condition: error reading from spamd socket: %s", strerror(errno)); | |
344 | (void)close(spamd_sock); | |
345 | return DEFER; | |
346 | } | |
347 | ||
348 | /* reading done */ | |
349 | (void)close(spamd_sock); | |
350 | ||
351 | /* dig in the spamd output and put the report in a multiline header, if requested */ | |
352 | if( sscanf(CS spamd_buffer,"SPAMD/%7s 0 EX_OK\r\nContent-length: %*u\r\n\r\n%lf/%lf\r\n%n", | |
353 | spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3 ) { | |
354 | ||
355 | /* try to fall back to pre-2.50 spamd output */ | |
356 | if( sscanf(CS spamd_buffer,"SPAMD/%7s 0 EX_OK\r\nSpam: %*s ; %lf / %lf\r\n\r\n%n", | |
357 | spamd_version,&spamd_score,&spamd_threshold,&spamd_report_offset) != 3 ) { | |
358 | log_write(0, LOG_MAIN|LOG_PANIC, | |
359 | "spam acl condition: cannot parse spamd output"); | |
360 | return DEFER; | |
361 | }; | |
362 | }; | |
363 | ||
364 | /* Create report. Since this is a multiline string, | |
365 | we must hack it into shape first */ | |
366 | p = &spamd_buffer[spamd_report_offset]; | |
367 | q = spam_report_buffer; | |
368 | while (*p != '\0') { | |
369 | /* skip \r */ | |
370 | if (*p == '\r') { | |
371 | p++; | |
372 | continue; | |
373 | }; | |
374 | *q = *p; | |
375 | q++; | |
376 | if (*p == '\n') { | |
377 | /* add an extra space after the newline to ensure | |
378 | that it is treated as a header continuation line */ | |
379 | *q = ' '; | |
380 | q++; | |
381 | }; | |
382 | p++; | |
383 | }; | |
384 | /* NULL-terminate */ | |
385 | *q = '\0'; | |
386 | q--; | |
387 | /* cut off trailing leftovers */ | |
388 | while (*q <= ' ') { | |
389 | *q = '\0'; | |
390 | q--; | |
391 | }; | |
392 | spam_report = spam_report_buffer; | |
393 | ||
394 | /* create spam bar */ | |
395 | spamd_score_char = spamd_score > 0 ? '+' : '-'; | |
396 | j = abs((int)(spamd_score)); | |
397 | i = 0; | |
398 | if( j != 0 ) { | |
399 | while((i < j) && (i <= MAX_SPAM_BAR_CHARS)) | |
400 | spam_bar_buffer[i++] = spamd_score_char; | |
401 | } | |
402 | else{ | |
403 | spam_bar_buffer[0] = '/'; | |
404 | i = 1; | |
405 | } | |
406 | spam_bar_buffer[i] = '\0'; | |
407 | spam_bar = spam_bar_buffer; | |
408 | ||
409 | /* create "float" spam score */ | |
410 | (void)string_format(spam_score_buffer, sizeof(spam_score_buffer),"%.1f", spamd_score); | |
411 | spam_score = spam_score_buffer; | |
412 | ||
413 | /* create "int" spam score */ | |
414 | j = (int)((spamd_score + 0.001)*10); | |
415 | (void)string_format(spam_score_int_buffer, sizeof(spam_score_int_buffer), "%d", j); | |
416 | spam_score_int = spam_score_int_buffer; | |
417 | ||
418 | /* compare threshold against score */ | |
419 | if (spamd_score >= spamd_threshold) { | |
420 | /* spam as determined by user's threshold */ | |
421 | spam_rc = OK; | |
422 | } | |
423 | else { | |
424 | /* not spam */ | |
425 | spam_rc = FAIL; | |
426 | }; | |
427 | ||
428 | /* remember expanded spamd_address if needed */ | |
429 | if (spamd_address_work != spamd_address) { | |
430 | prev_spamd_address_work = string_copy(spamd_address_work); | |
431 | } | |
432 | /* remember user name and "been here" for it */ | |
433 | Ustrcpy(prev_user_name, user_name); | |
434 | spam_ok = 1; | |
435 | ||
436 | if (override) { | |
437 | /* always return OK, no matter what the score */ | |
438 | return OK; | |
439 | } | |
440 | else { | |
441 | return spam_rc; | |
442 | }; | |
443 | } | |
444 | ||
445 | #endif |