Commit | Line | Data |
---|---|---|
420a0d19 CE |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
2ea97746 CE |
5 | /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004 - 2015 |
6 | * License: GPL | |
7 | * Copyright (c) The Exim Maintainers 2015 - 2018 | |
8 | */ | |
420a0d19 CE |
9 | |
10 | #include "exim.h" | |
11 | #ifdef WITH_CONTENT_SCAN /* entire file */ | |
12 | #include "mime.h" | |
13 | #include <sys/stat.h> | |
14 | ||
15 | FILE *mime_stream = NULL; | |
16 | uschar *mime_current_boundary = NULL; | |
17 | ||
2ea97746 CE |
18 | static mime_header mime_header_list[] = { |
19 | /* name namelen value */ | |
20 | { US"content-type:", 13, &mime_content_type }, | |
21 | { US"content-disposition:", 20, &mime_content_disposition }, | |
22 | { US"content-transfer-encoding:", 26, &mime_content_transfer_encoding }, | |
23 | { US"content-id:", 11, &mime_content_id }, | |
24 | { US"content-description:", 20, &mime_content_description } | |
25 | }; | |
26 | ||
27 | static int mime_header_list_size = nelem(mime_header_list); | |
28 | ||
29 | static mime_parameter mime_parameter_list[] = { | |
30 | /* name namelen value */ | |
31 | { US"name=", 5, &mime_filename }, | |
32 | { US"filename=", 9, &mime_filename }, | |
33 | { US"charset=", 8, &mime_charset }, | |
34 | { US"boundary=", 9, &mime_boundary } | |
35 | }; | |
36 | ||
37 | ||
420a0d19 CE |
38 | /************************************************* |
39 | * set MIME anomaly level + text * | |
40 | *************************************************/ | |
41 | ||
42 | /* Small wrapper to set the two expandables which | |
43 | give info on detected "problems" in MIME | |
2ea97746 | 44 | encodings. Indexes are defined in mime.h. */ |
420a0d19 CE |
45 | |
46 | void | |
2ea97746 | 47 | mime_set_anomaly(int idx) |
420a0d19 | 48 | { |
2ea97746 CE |
49 | struct anom { |
50 | int level; | |
51 | const uschar * text; | |
52 | } anom[] = { {1, CUS"Broken Quoted-Printable encoding detected"}, | |
53 | {2, CUS"Broken BASE64 encoding detected"} }; | |
54 | ||
55 | mime_anomaly_level = anom[idx].level; | |
56 | mime_anomaly_text = anom[idx].text; | |
420a0d19 CE |
57 | } |
58 | ||
59 | ||
60 | /************************************************* | |
61 | * decode quoted-printable chars * | |
62 | *************************************************/ | |
63 | ||
64 | /* gets called when we hit a = | |
65 | returns: new pointer position | |
66 | result code in c: | |
67 | -2 - decode error | |
68 | -1 - soft line break, no char | |
69 | 0-255 - char to write | |
70 | */ | |
71 | ||
2ea97746 | 72 | static uschar * |
420a0d19 CE |
73 | mime_decode_qp_char(uschar *qp_p, int *c) |
74 | { | |
75 | uschar *initial_pos = qp_p; | |
76 | ||
77 | /* advance one char */ | |
78 | qp_p++; | |
79 | ||
80 | /* Check for two hex digits and decode them */ | |
81 | if (isxdigit(*qp_p) && isxdigit(qp_p[1])) | |
82 | { | |
83 | /* Do hex conversion */ | |
84 | *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) <<4; | |
85 | qp_p++; | |
86 | *c |= isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10; | |
87 | return qp_p + 1; | |
88 | } | |
89 | ||
90 | /* tab or whitespace may follow just ignore it if it precedes \n */ | |
91 | while (*qp_p == '\t' || *qp_p == ' ' || *qp_p == '\r') | |
92 | qp_p++; | |
93 | ||
94 | if (*qp_p == '\n') /* hit soft line break */ | |
95 | { | |
96 | *c = -1; | |
97 | return qp_p; | |
98 | } | |
99 | ||
100 | /* illegal char here */ | |
101 | *c = -2; | |
102 | return initial_pos; | |
103 | } | |
104 | ||
105 | ||
106 | /* just dump MIME part without any decoding */ | |
107 | static ssize_t | |
108 | mime_decode_asis(FILE* in, FILE* out, uschar* boundary) | |
109 | { | |
110 | ssize_t len, size = 0; | |
111 | uschar buffer[MIME_MAX_LINE_LENGTH]; | |
112 | ||
113 | while(fgets(CS buffer, MIME_MAX_LINE_LENGTH, mime_stream) != NULL) | |
114 | { | |
115 | if (boundary != NULL | |
116 | && Ustrncmp(buffer, "--", 2) == 0 | |
117 | && Ustrncmp((buffer+2), boundary, Ustrlen(boundary)) == 0 | |
118 | ) | |
119 | break; | |
120 | ||
121 | len = Ustrlen(buffer); | |
122 | if (fwrite(buffer, 1, (size_t)len, out) < len) | |
123 | return -1; | |
124 | size += len; | |
125 | } /* while */ | |
126 | return size; | |
127 | } | |
128 | ||
129 | ||
420a0d19 CE |
130 | |
131 | /* decode quoted-printable MIME part */ | |
132 | static ssize_t | |
133 | mime_decode_qp(FILE* in, FILE* out, uschar* boundary) | |
134 | { | |
135 | uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH]; | |
136 | uschar *ipos, *opos; | |
137 | ssize_t len, size = 0; | |
138 | ||
139 | while (fgets(CS ibuf, MIME_MAX_LINE_LENGTH, in) != NULL) | |
140 | { | |
141 | if (boundary != NULL | |
142 | && Ustrncmp(ibuf, "--", 2) == 0 | |
143 | && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0 | |
144 | ) | |
145 | break; /* todo: check for missing boundary */ | |
146 | ||
147 | ipos = ibuf; | |
148 | opos = obuf; | |
149 | ||
150 | while (*ipos != 0) | |
151 | { | |
152 | if (*ipos == '=') | |
153 | { | |
154 | int decode_qp_result; | |
155 | ||
156 | ipos = mime_decode_qp_char(ipos, &decode_qp_result); | |
157 | ||
158 | if (decode_qp_result == -2) | |
159 | { | |
160 | /* Error from decoder. ipos is unchanged. */ | |
161 | mime_set_anomaly(MIME_ANOMALY_BROKEN_QP); | |
2ea97746 | 162 | *opos++ = '='; |
420a0d19 CE |
163 | ++ipos; |
164 | } | |
165 | else if (decode_qp_result == -1) | |
166 | break; | |
167 | else if (decode_qp_result >= 0) | |
2ea97746 | 168 | *opos++ = decode_qp_result; |
420a0d19 CE |
169 | } |
170 | else | |
2ea97746 | 171 | *opos++ = *ipos++; |
420a0d19 CE |
172 | } |
173 | /* something to write? */ | |
174 | len = opos - obuf; | |
175 | if (len > 0) | |
176 | { | |
177 | if (fwrite(obuf, 1, len, out) != len) return -1; /* error */ | |
178 | size += len; | |
179 | } | |
180 | } | |
181 | return size; | |
182 | } | |
183 | ||
184 | ||
2ea97746 CE |
185 | /* |
186 | * Return open filehandle for combo of path and file. | |
187 | * Side-effect: set mime_decoded_filename, to copy in allocated mem | |
188 | */ | |
189 | static FILE * | |
420a0d19 CE |
190 | mime_get_decode_file(uschar *pname, uschar *fname) |
191 | { | |
420a0d19 | 192 | if (pname && fname) |
2ea97746 | 193 | mime_decoded_filename = string_sprintf("%s/%s", pname, fname); |
420a0d19 | 194 | else if (!pname) |
2ea97746 | 195 | mime_decoded_filename = string_copy(fname); |
420a0d19 CE |
196 | else if (!fname) |
197 | { | |
198 | int file_nr = 0; | |
199 | int result = 0; | |
200 | ||
201 | /* must find first free sequential filename */ | |
202 | do | |
203 | { | |
204 | struct stat mystat; | |
2ea97746 | 205 | mime_decoded_filename = string_sprintf("%s/%s-%05u", pname, message_id, file_nr++); |
420a0d19 CE |
206 | /* security break */ |
207 | if (file_nr >= 1024) | |
208 | break; | |
2ea97746 | 209 | result = stat(CS mime_decoded_filename, &mystat); |
420a0d19 | 210 | } while(result != -1); |
420a0d19 CE |
211 | } |
212 | ||
2ea97746 | 213 | return modefopen(mime_decoded_filename, "wb+", SPOOL_MODE); |
420a0d19 CE |
214 | } |
215 | ||
216 | ||
217 | int | |
2ea97746 | 218 | mime_decode(const uschar **listptr) |
420a0d19 CE |
219 | { |
220 | int sep = 0; | |
2ea97746 CE |
221 | const uschar *list = *listptr; |
222 | uschar * option; | |
223 | uschar * decode_path; | |
420a0d19 CE |
224 | FILE *decode_file = NULL; |
225 | long f_pos = 0; | |
226 | ssize_t size_counter = 0; | |
227 | ssize_t (*decode_function)(FILE*, FILE*, uschar*); | |
228 | ||
2ea97746 | 229 | if (!mime_stream || (f_pos = ftell(mime_stream)) < 0) |
420a0d19 CE |
230 | return FAIL; |
231 | ||
420a0d19 | 232 | /* build default decode path (will exist since MBOX must be spooled up) */ |
2ea97746 | 233 | decode_path = string_sprintf("%s/scan/%s", spool_directory, message_id); |
420a0d19 CE |
234 | |
235 | /* try to find 1st option */ | |
2ea97746 | 236 | if ((option = string_nextinlist(&list, &sep, NULL, 0))) |
420a0d19 CE |
237 | { |
238 | /* parse 1st option */ | |
2ea97746 | 239 | if ((Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0)) |
420a0d19 CE |
240 | /* explicitly no decoding */ |
241 | return FAIL; | |
242 | ||
243 | if (Ustrcmp(option,"default") == 0) | |
244 | /* explicit default path + file names */ | |
245 | goto DEFAULT_PATH; | |
246 | ||
247 | if (option[0] == '/') | |
248 | { | |
249 | struct stat statbuf; | |
250 | ||
251 | memset(&statbuf,0,sizeof(statbuf)); | |
252 | ||
253 | /* assume either path or path+file name */ | |
254 | if ( (stat(CS option, &statbuf) == 0) && S_ISDIR(statbuf.st_mode) ) | |
255 | /* is directory, use it as decode_path */ | |
256 | decode_file = mime_get_decode_file(option, NULL); | |
257 | else | |
258 | /* does not exist or is a file, use as full file name */ | |
259 | decode_file = mime_get_decode_file(NULL, option); | |
260 | } | |
261 | else | |
262 | /* assume file name only, use default path */ | |
263 | decode_file = mime_get_decode_file(decode_path, option); | |
264 | } | |
265 | else | |
266 | { | |
267 | /* no option? patch default path */ | |
268 | DEFAULT_PATH: | |
269 | decode_file = mime_get_decode_file(decode_path, NULL); | |
270 | } | |
271 | ||
272 | if (!decode_file) | |
273 | return DEFER; | |
274 | ||
275 | /* decode according to mime type */ | |
276 | decode_function = | |
277 | !mime_content_transfer_encoding | |
278 | ? mime_decode_asis /* no encoding, dump as-is */ | |
279 | : Ustrcmp(mime_content_transfer_encoding, "base64") == 0 | |
280 | ? mime_decode_base64 | |
281 | : Ustrcmp(mime_content_transfer_encoding, "quoted-printable") == 0 | |
282 | ? mime_decode_qp | |
283 | : mime_decode_asis; /* unknown encoding type, just dump as-is */ | |
284 | ||
285 | size_counter = decode_function(mime_stream, decode_file, mime_current_boundary); | |
286 | ||
287 | clearerr(mime_stream); | |
2ea97746 CE |
288 | if (fseek(mime_stream, f_pos, SEEK_SET)) |
289 | return DEFER; | |
420a0d19 CE |
290 | |
291 | if (fclose(decode_file) != 0 || size_counter < 0) | |
292 | return DEFER; | |
293 | ||
294 | /* round up to the next KiB */ | |
295 | mime_content_size = (size_counter + 1023) / 1024; | |
296 | ||
297 | return OK; | |
298 | } | |
299 | ||
2ea97746 CE |
300 | |
301 | static int | |
420a0d19 CE |
302 | mime_get_header(FILE *f, uschar *header) |
303 | { | |
304 | int c = EOF; | |
305 | int done = 0; | |
306 | int header_value_mode = 0; | |
307 | int header_open_brackets = 0; | |
308 | int num_copied = 0; | |
309 | ||
310 | while(!done) | |
311 | { | |
312 | if ((c = fgetc(f)) == EOF) break; | |
313 | ||
314 | /* always skip CRs */ | |
315 | if (c == '\r') continue; | |
316 | ||
317 | if (c == '\n') | |
318 | { | |
319 | if (num_copied > 0) | |
320 | { | |
321 | /* look if next char is '\t' or ' ' */ | |
322 | if ((c = fgetc(f)) == EOF) break; | |
323 | if ( (c == '\t') || (c == ' ') ) continue; | |
324 | (void)ungetc(c,f); | |
325 | } | |
326 | /* end of the header, terminate with ';' */ | |
327 | c = ';'; | |
328 | done = 1; | |
329 | } | |
330 | ||
331 | /* skip control characters */ | |
332 | if (c < 32) continue; | |
333 | ||
334 | if (header_value_mode) | |
335 | { | |
336 | /* --------- value mode ----------- */ | |
337 | /* skip leading whitespace */ | |
338 | if ( ((c == '\t') || (c == ' ')) && (header_value_mode == 1) ) | |
339 | continue; | |
340 | ||
2ea97746 CE |
341 | /* we have hit a non-whitespace char, start copying value data */ |
342 | header_value_mode = 2; | |
420a0d19 | 343 | |
2ea97746 CE |
344 | if (c == '"') /* flip "quoted" mode */ |
345 | header_value_mode = header_value_mode==2 ? 3 : 2; | |
420a0d19 | 346 | |
2ea97746 CE |
347 | /* leave value mode on unquoted ';' */ |
348 | if (header_value_mode == 2 && c == ';') | |
349 | header_value_mode = 0; | |
350 | /* -------------------------------- */ | |
420a0d19 CE |
351 | } |
352 | else | |
353 | { | |
354 | /* -------- non-value mode -------- */ | |
355 | /* skip whitespace + tabs */ | |
356 | if ( (c == ' ') || (c == '\t') ) | |
357 | continue; | |
358 | if (c == '\\') | |
359 | { | |
360 | /* quote next char. can be used | |
361 | to escape brackets. */ | |
362 | if ((c = fgetc(f)) == EOF) break; | |
363 | } | |
364 | else if (c == '(') | |
365 | { | |
366 | header_open_brackets++; | |
367 | continue; | |
368 | } | |
369 | else if ((c == ')') && header_open_brackets) | |
370 | { | |
371 | header_open_brackets--; | |
372 | continue; | |
373 | } | |
374 | else if ( (c == '=') && !header_open_brackets ) /* enter value mode */ | |
375 | header_value_mode = 1; | |
376 | ||
377 | /* skip chars while we are in a comment */ | |
378 | if (header_open_brackets > 0) | |
379 | continue; | |
380 | /* -------------------------------- */ | |
381 | } | |
382 | ||
383 | /* copy the char to the buffer */ | |
384 | header[num_copied++] = (uschar)c; | |
385 | ||
386 | /* break if header buffer is full */ | |
387 | if (num_copied > MIME_MAX_HEADER_SIZE-1) | |
388 | done = 1; | |
389 | } | |
390 | ||
391 | if ((num_copied > 0) && (header[num_copied-1] != ';')) | |
392 | header[num_copied-1] = ';'; | |
393 | ||
394 | /* 0-terminate */ | |
395 | header[num_copied] = '\0'; | |
396 | ||
397 | /* return 0 for EOF or empty line */ | |
398 | if ((c == EOF) || (num_copied == 1)) | |
399 | return 0; | |
400 | else | |
401 | return 1; | |
402 | } | |
403 | ||
404 | ||
2ea97746 CE |
405 | static void |
406 | mime_vars_reset(void) | |
407 | { | |
408 | mime_anomaly_level = 0; | |
409 | mime_anomaly_text = NULL; | |
410 | mime_boundary = NULL; | |
411 | mime_charset = NULL; | |
412 | mime_decoded_filename = NULL; | |
413 | mime_filename = NULL; | |
414 | mime_content_description = NULL; | |
415 | mime_content_disposition = NULL; | |
416 | mime_content_id = NULL; | |
417 | mime_content_transfer_encoding = NULL; | |
418 | mime_content_type = NULL; | |
419 | mime_is_multipart = 0; | |
420 | mime_content_size = 0; | |
421 | } | |
422 | ||
423 | ||
424 | /* Grab a parameter value, dealing with quoting. | |
425 | ||
426 | Arguments: | |
427 | str Input string. Updated on return to point to terminating ; or NUL | |
428 | ||
429 | Return: | |
430 | Allocated string with parameter value | |
431 | */ | |
432 | static uschar * | |
433 | mime_param_val(uschar ** sp) | |
434 | { | |
435 | uschar * s = *sp; | |
436 | gstring * val = NULL; | |
437 | ||
438 | /* debug_printf_indent(" considering paramval '%s'\n", s); */ | |
439 | ||
440 | while (*s && *s != ';') /* ; terminates */ | |
441 | if (*s == '"') | |
442 | { | |
443 | s++; /* skip opening " */ | |
444 | while (*s && *s != '"') /* " protects ; */ | |
445 | val = string_catn(val, s++, 1); | |
446 | if (*s) s++; /* skip closing " */ | |
447 | } | |
448 | else | |
449 | val = string_catn(val, s++, 1); | |
450 | *sp = s; | |
451 | return string_from_gstring(val); | |
452 | } | |
453 | ||
454 | static uschar * | |
455 | mime_next_semicolon(uschar * s) | |
456 | { | |
457 | while (*s && *s != ';') /* ; terminates */ | |
458 | if (*s == '"') | |
459 | { | |
460 | s++; /* skip opening " */ | |
461 | while (*s && *s != '"') /* " protects ; */ | |
462 | s++; | |
463 | if (*s) s++; /* skip closing " */ | |
464 | } | |
465 | else | |
466 | s++; | |
467 | return s; | |
468 | } | |
469 | ||
470 | ||
471 | static uschar * | |
472 | rfc2231_to_2047(const uschar * fname, const uschar * charset, int * len) | |
473 | { | |
474 | gstring * val = string_catn(NULL, US"=?", 2); | |
475 | uschar c; | |
476 | ||
477 | if (charset) | |
478 | val = string_cat(val, charset); | |
479 | val = string_catn(val, US"?Q?", 3); | |
480 | ||
481 | while ((c = *fname)) | |
482 | if (c == '%' && isxdigit(fname[1]) && isxdigit(fname[2])) | |
483 | { | |
484 | val = string_catn(val, US"=", 1); | |
485 | val = string_catn(val, ++fname, 2); | |
486 | fname += 2; | |
487 | } | |
488 | else | |
489 | val = string_catn(val, fname++, 1); | |
490 | ||
491 | val = string_catn(val, US"?=", 2); | |
492 | *len = val->ptr; | |
493 | return string_from_gstring(val); | |
494 | } | |
495 | ||
496 | ||
420a0d19 CE |
497 | int |
498 | mime_acl_check(uschar *acl, FILE *f, struct mime_boundary_context *context, | |
2ea97746 | 499 | uschar **user_msgptr, uschar **log_msgptr) |
420a0d19 CE |
500 | { |
501 | int rc = OK; | |
2ea97746 | 502 | uschar * header = NULL; |
420a0d19 CE |
503 | struct mime_boundary_context nested_context; |
504 | ||
505 | /* reserve a line buffer to work in */ | |
2ea97746 | 506 | header = store_get(MIME_MAX_HEADER_SIZE+1); |
420a0d19 CE |
507 | |
508 | /* Not actually used at the moment, but will be vital to fixing | |
509 | * some RFC 2046 nonconformance later... */ | |
510 | nested_context.parent = context; | |
511 | ||
512 | /* loop through parts */ | |
513 | while(1) | |
514 | { | |
515 | /* reset all per-part mime variables */ | |
2ea97746 CE |
516 | mime_vars_reset(); |
517 | ||
518 | /* If boundary is null, we assume that *f is positioned on the start of | |
519 | headers (for example, at the very beginning of a message. If a boundary is | |
520 | given, we must first advance to it to reach the start of the next header | |
521 | block. */ | |
420a0d19 CE |
522 | |
523 | /* NOTE -- there's an error here -- RFC2046 specifically says to | |
524 | * check for outer boundaries. This code doesn't do that, and | |
525 | * I haven't fixed this. | |
526 | * | |
527 | * (I have moved partway towards adding support, however, by adding | |
528 | * a "parent" field to my new boundary-context structure.) | |
529 | */ | |
2ea97746 | 530 | if (context) for (;;) |
420a0d19 | 531 | { |
2ea97746 | 532 | if (!fgets(CS header, MIME_MAX_HEADER_SIZE, f)) |
420a0d19 | 533 | { |
2ea97746 CE |
534 | /* Hit EOF or read error. Ugh. */ |
535 | DEBUG(D_acl) debug_printf_indent("MIME: Hit EOF ...\n"); | |
536 | return rc; | |
537 | } | |
420a0d19 | 538 | |
2ea97746 CE |
539 | /* boundary line must start with 2 dashes */ |
540 | if ( Ustrncmp(header, "--", 2) == 0 | |
541 | && Ustrncmp(header+2, context->boundary, Ustrlen(context->boundary)) == 0 | |
542 | ) | |
543 | { /* found boundary */ | |
544 | if (Ustrncmp((header+2+Ustrlen(context->boundary)), "--", 2) == 0) | |
545 | { | |
546 | /* END boundary found */ | |
547 | DEBUG(D_acl) debug_printf_indent("MIME: End boundary found %s\n", | |
548 | context->boundary); | |
549 | return rc; | |
420a0d19 | 550 | } |
2ea97746 CE |
551 | |
552 | DEBUG(D_acl) debug_printf_indent("MIME: Next part with boundary %s\n", | |
553 | context->boundary); | |
554 | break; | |
420a0d19 | 555 | } |
420a0d19 CE |
556 | } |
557 | ||
420a0d19 | 558 | /* parse headers, set up expansion variables */ |
2ea97746 | 559 | while (mime_get_header(f, header)) |
420a0d19 | 560 | { |
2ea97746 CE |
561 | struct mime_header * mh; |
562 | ||
563 | /* look for interesting headers */ | |
564 | for (mh = mime_header_list; | |
565 | mh < mime_header_list + mime_header_list_size; | |
566 | mh++) if (strncmpic(mh->name, header, mh->namelen) == 0) | |
420a0d19 | 567 | { |
2ea97746 CE |
568 | uschar * p = header + mh->namelen; |
569 | uschar * q; | |
570 | ||
571 | /* grab the value (normalize to lower case) | |
572 | and copy to its corresponding expansion variable */ | |
573 | ||
574 | for (q = p; *q != ';' && *q; q++) ; | |
575 | *mh->value = string_copynlc(p, q-p); | |
576 | DEBUG(D_acl) debug_printf_indent("MIME: found %s header, value is '%s'\n", | |
577 | mh->name, *mh->value); | |
578 | ||
579 | if (*(p = q)) p++; /* jump past the ; */ | |
420a0d19 | 580 | |
420a0d19 | 581 | { |
2ea97746 CE |
582 | uschar * mime_fname = NULL; |
583 | uschar * mime_fname_rfc2231 = NULL; | |
584 | uschar * mime_filename_charset = NULL; | |
585 | BOOL decoding_failed = FALSE; | |
586 | ||
587 | /* grab all param=value tags on the remaining line, | |
588 | check if they are interesting */ | |
589 | ||
590 | while (*p) | |
420a0d19 CE |
591 | { |
592 | mime_parameter * mp; | |
2ea97746 CE |
593 | |
594 | DEBUG(D_acl) debug_printf_indent("MIME: considering paramlist '%s'\n", p); | |
595 | ||
596 | if ( !mime_filename | |
597 | && strncmpic(CUS"content-disposition:", header, 20) == 0 | |
598 | && strncmpic(CUS"filename*", p, 9) == 0 | |
599 | ) | |
600 | { /* RFC 2231 filename */ | |
601 | uschar * q; | |
602 | ||
603 | /* find value of the filename */ | |
604 | p += 9; | |
605 | while(*p != '=' && *p) p++; | |
606 | if (*p) p++; /* p is filename or NUL */ | |
607 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
608 | ||
609 | if (q && *q) | |
420a0d19 | 610 | { |
2ea97746 CE |
611 | uschar * temp_string, * err_msg; |
612 | int slen; | |
420a0d19 | 613 | |
2ea97746 CE |
614 | /* build up an un-decoded filename over successive |
615 | filename*= parameters (for use when 2047 decode fails) */ | |
616 | ||
617 | mime_fname_rfc2231 = string_sprintf("%#s%s", | |
618 | mime_fname_rfc2231, q); | |
619 | ||
620 | if (!decoding_failed) | |
420a0d19 | 621 | { |
2ea97746 CE |
622 | int size; |
623 | if (!mime_filename_charset) | |
420a0d19 | 624 | { |
2ea97746 CE |
625 | uschar * s = q; |
626 | ||
627 | /* look for a ' in the "filename" */ | |
628 | while(*s != '\'' && *s) s++; /* s is 1st ' or NUL */ | |
629 | ||
630 | if ((size = s-q) > 0) | |
631 | mime_filename_charset = string_copyn(q, size); | |
632 | ||
633 | if (*(p = s)) p++; | |
634 | while(*p == '\'') p++; /* p is after 2nd ' */ | |
420a0d19 CE |
635 | } |
636 | else | |
2ea97746 CE |
637 | p = q; |
638 | ||
639 | DEBUG(D_acl) debug_printf_indent("MIME: charset %s fname '%s'\n", | |
640 | mime_filename_charset ? mime_filename_charset : US"<NULL>", p); | |
641 | ||
642 | temp_string = rfc2231_to_2047(p, mime_filename_charset, &slen); | |
643 | DEBUG(D_acl) debug_printf_indent("MIME: 2047-name %s\n", temp_string); | |
644 | ||
645 | temp_string = rfc2047_decode(temp_string, FALSE, NULL, ' ', | |
646 | NULL, &err_msg); | |
647 | DEBUG(D_acl) debug_printf_indent("MIME: plain-name %s\n", temp_string); | |
648 | ||
649 | if (!temp_string || (size = Ustrlen(temp_string)) == slen) | |
650 | decoding_failed = TRUE; | |
651 | else | |
652 | /* build up a decoded filename over successive | |
653 | filename*= parameters */ | |
654 | ||
655 | mime_filename = mime_fname = mime_fname | |
656 | ? string_sprintf("%s%s", mime_fname, temp_string) | |
657 | : temp_string; | |
420a0d19 | 658 | } |
2ea97746 | 659 | } |
420a0d19 | 660 | } |
2ea97746 CE |
661 | |
662 | else | |
663 | /* look for interesting parameters */ | |
664 | for (mp = mime_parameter_list; | |
665 | mp < mime_parameter_list + nelem(mime_parameter_list); | |
666 | mp++ | |
667 | ) if (strncmpic(mp->name, p, mp->namelen) == 0) | |
668 | { | |
669 | uschar * q; | |
670 | uschar * dummy_errstr; | |
671 | ||
672 | /* grab the value and copy to its expansion variable */ | |
673 | p += mp->namelen; | |
674 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
675 | ||
676 | *mp->value = q && *q | |
677 | ? rfc2047_decode(q, check_rfc2047_length, NULL, 32, NULL, | |
678 | &dummy_errstr) | |
679 | : NULL; | |
680 | DEBUG(D_acl) debug_printf_indent( | |
681 | "MIME: found %s parameter in %s header, value '%s'\n", | |
682 | mp->name, mh->name, *mp->value); | |
683 | ||
684 | break; /* done matching param names */ | |
685 | } | |
686 | ||
687 | ||
420a0d19 | 688 | /* There is something, but not one of our interesting parameters. |
2ea97746 CE |
689 | Advance past the next semicolon */ |
690 | p = mime_next_semicolon(p); | |
691 | if (*p) p++; | |
692 | } /* param scan on line */ | |
693 | ||
694 | if (strncmpic(CUS"content-disposition:", header, 20) == 0) | |
695 | { | |
696 | if (decoding_failed) mime_filename = mime_fname_rfc2231; | |
697 | ||
698 | DEBUG(D_acl) debug_printf_indent( | |
699 | "MIME: found %s parameter in %s header, value is '%s'\n", | |
700 | "filename", mh->name, mime_filename); | |
701 | } | |
420a0d19 CE |
702 | } |
703 | } | |
704 | } | |
420a0d19 CE |
705 | |
706 | /* set additional flag variables (easier access) */ | |
2ea97746 CE |
707 | if ( mime_content_type |
708 | && Ustrncmp(mime_content_type,"multipart",9) == 0 | |
709 | ) | |
420a0d19 CE |
710 | mime_is_multipart = 1; |
711 | ||
712 | /* Make a copy of the boundary pointer. | |
713 | Required since mime_boundary is global | |
714 | and can be overwritten further down in recursion */ | |
715 | nested_context.boundary = mime_boundary; | |
716 | ||
717 | /* raise global counter */ | |
718 | mime_part_count++; | |
719 | ||
720 | /* copy current file handle to global variable */ | |
721 | mime_stream = f; | |
722 | mime_current_boundary = context ? context->boundary : 0; | |
723 | ||
724 | /* Note the context */ | |
725 | mime_is_coverletter = !(context && context->context == MBC_ATTACHMENT); | |
726 | ||
727 | /* call ACL handling function */ | |
728 | rc = acl_check(ACL_WHERE_MIME, NULL, acl, user_msgptr, log_msgptr); | |
729 | ||
730 | mime_stream = NULL; | |
731 | mime_current_boundary = NULL; | |
732 | ||
733 | if (rc != OK) break; | |
734 | ||
735 | /* If we have a multipart entity and a boundary, go recursive */ | |
736 | if ( (mime_content_type != NULL) && | |
737 | (nested_context.boundary != NULL) && | |
738 | (Ustrncmp(mime_content_type,"multipart",9) == 0) ) | |
739 | { | |
2ea97746 CE |
740 | DEBUG(D_acl) |
741 | debug_printf_indent("MIME: Entering multipart recursion, boundary '%s'\n", | |
742 | nested_context.boundary); | |
420a0d19 CE |
743 | |
744 | nested_context.context = | |
745 | context && context->context == MBC_ATTACHMENT | |
746 | ? MBC_ATTACHMENT | |
747 | : Ustrcmp(mime_content_type,"multipart/alternative") == 0 | |
748 | || Ustrcmp(mime_content_type,"multipart/related") == 0 | |
749 | ? MBC_COVERLETTER_ALL | |
750 | : MBC_COVERLETTER_ONESHOT; | |
751 | ||
752 | rc = mime_acl_check(acl, f, &nested_context, user_msgptr, log_msgptr); | |
753 | if (rc != OK) break; | |
754 | } | |
755 | else if ( (mime_content_type != NULL) && | |
756 | (Ustrncmp(mime_content_type,"message/rfc822",14) == 0) ) | |
757 | { | |
2ea97746 | 758 | const uschar *rfc822name = NULL; |
420a0d19 CE |
759 | uschar filename[2048]; |
760 | int file_nr = 0; | |
761 | int result = 0; | |
762 | ||
763 | /* must find first free sequential filename */ | |
764 | do | |
765 | { | |
766 | struct stat mystat; | |
767 | (void)string_format(filename, 2048, | |
768 | "%s/scan/%s/__rfc822_%05u", spool_directory, message_id, file_nr++); | |
769 | /* security break */ | |
770 | if (file_nr >= 128) | |
771 | goto NO_RFC822; | |
772 | result = stat(CS filename,&mystat); | |
773 | } while (result != -1); | |
774 | ||
775 | rfc822name = filename; | |
776 | ||
777 | /* decode RFC822 attachment */ | |
778 | mime_decoded_filename = NULL; | |
779 | mime_stream = f; | |
780 | mime_current_boundary = context ? context->boundary : NULL; | |
781 | mime_decode(&rfc822name); | |
782 | mime_stream = NULL; | |
783 | mime_current_boundary = NULL; | |
784 | if (!mime_decoded_filename) /* decoding failed */ | |
785 | { | |
786 | log_write(0, LOG_MAIN, | |
2ea97746 CE |
787 | "MIME acl condition warning - could not decode RFC822 MIME part to file."); |
788 | rc = DEFER; | |
789 | goto out; | |
420a0d19 CE |
790 | } |
791 | mime_decoded_filename = NULL; | |
792 | } | |
793 | ||
794 | NO_RFC822: | |
795 | /* If the boundary of this instance is NULL, we are finished here */ | |
2ea97746 | 796 | if (!context) break; |
420a0d19 CE |
797 | |
798 | if (context->context == MBC_COVERLETTER_ONESHOT) | |
799 | context->context = MBC_ATTACHMENT; | |
800 | } | |
801 | ||
2ea97746 CE |
802 | out: |
803 | mime_vars_reset(); | |
420a0d19 CE |
804 | return rc; |
805 | } | |
806 | ||
807 | #endif /*WITH_CONTENT_SCAN*/ | |
808 | ||
809 | /* vi: sw ai sw=2 | |
810 | */ |