Commit | Line | Data |
---|---|---|
8523533c TK |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
3386088d | 5 | /* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004, 2015 */ |
8523533c TK |
6 | /* License: GPL */ |
7 | ||
8 | #include "exim.h" | |
c007c974 | 9 | #ifdef WITH_CONTENT_SCAN /* entire file */ |
8523533c TK |
10 | #include "mime.h" |
11 | #include <sys/stat.h> | |
12 | ||
13 | FILE *mime_stream = NULL; | |
14 | uschar *mime_current_boundary = NULL; | |
15 | ||
16 | /************************************************* | |
17 | * set MIME anomaly level + text * | |
18 | *************************************************/ | |
19 | ||
20 | /* Small wrapper to set the two expandables which | |
21 | give info on detected "problems" in MIME | |
22 | encodings. Those are defined in mime.h. */ | |
23 | ||
f846c8f5 | 24 | static void |
c007c974 JH |
25 | mime_set_anomaly(int level, const char *text) |
26 | { | |
8523533c | 27 | mime_anomaly_level = level; |
1ba28e2b | 28 | mime_anomaly_text = CUS text; |
f7b63901 | 29 | } |
8523533c TK |
30 | |
31 | ||
32 | /************************************************* | |
33 | * decode quoted-printable chars * | |
34 | *************************************************/ | |
35 | ||
36 | /* gets called when we hit a = | |
37 | returns: new pointer position | |
38 | result code in c: | |
39 | -2 - decode error | |
40 | -1 - soft line break, no char | |
41 | 0-255 - char to write | |
42 | */ | |
43 | ||
f846c8f5 | 44 | static uschar * |
c007c974 JH |
45 | mime_decode_qp_char(uschar *qp_p, int *c) |
46 | { | |
47 | uschar *initial_pos = qp_p; | |
48 | ||
49 | /* advance one char */ | |
50 | qp_p++; | |
51 | ||
52 | /* Check for two hex digits and decode them */ | |
53 | if (isxdigit(*qp_p) && isxdigit(qp_p[1])) | |
54 | { | |
55 | /* Do hex conversion */ | |
56 | *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) <<4; | |
57 | qp_p++; | |
58 | *c |= isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10; | |
59 | return qp_p + 1; | |
60 | } | |
8e669ac1 | 61 | |
c007c974 JH |
62 | /* tab or whitespace may follow just ignore it if it precedes \n */ |
63 | while (*qp_p == '\t' || *qp_p == ' ' || *qp_p == '\r') | |
8523533c | 64 | qp_p++; |
8e669ac1 | 65 | |
c007c974 JH |
66 | if (*qp_p == '\n') /* hit soft line break */ |
67 | { | |
68 | *c = -1; | |
69 | return qp_p; | |
70 | } | |
71 | ||
72 | /* illegal char here */ | |
73 | *c = -2; | |
74 | return initial_pos; | |
8523533c TK |
75 | } |
76 | ||
77 | ||
baee9eee | 78 | /* just dump MIME part without any decoding */ |
eb02738d PP |
79 | static ssize_t |
80 | mime_decode_asis(FILE* in, FILE* out, uschar* boundary) | |
baee9eee | 81 | { |
eb02738d | 82 | ssize_t len, size = 0; |
baee9eee | 83 | uschar buffer[MIME_MAX_LINE_LENGTH]; |
d203e649 | 84 | |
c007c974 JH |
85 | while(fgets(CS buffer, MIME_MAX_LINE_LENGTH, mime_stream) != NULL) |
86 | { | |
baee9eee | 87 | if (boundary != NULL |
c007c974 JH |
88 | && Ustrncmp(buffer, "--", 2) == 0 |
89 | && Ustrncmp((buffer+2), boundary, Ustrlen(boundary)) == 0 | |
90 | ) | |
baee9eee NM |
91 | break; |
92 | ||
93 | len = Ustrlen(buffer); | |
94 | if (fwrite(buffer, 1, (size_t)len, out) < len) | |
95 | return -1; | |
96 | size += len; | |
c007c974 | 97 | } /* while */ |
baee9eee NM |
98 | return size; |
99 | } | |
84330b7b | 100 | |
8523533c | 101 | |
baee9eee | 102 | /* decode base64 MIME part */ |
eb02738d PP |
103 | static ssize_t |
104 | mime_decode_base64(FILE* in, FILE* out, uschar* boundary) | |
baee9eee NM |
105 | { |
106 | uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH]; | |
107 | uschar *ipos, *opos; | |
eb02738d | 108 | ssize_t len, size = 0; |
baee9eee NM |
109 | int bytestate = 0; |
110 | ||
111 | opos = obuf; | |
112 | ||
7156b1ef | 113 | while (Ufgets(ibuf, MIME_MAX_LINE_LENGTH, in) != NULL) |
c007c974 | 114 | { |
baee9eee | 115 | if (boundary != NULL |
c007c974 JH |
116 | && Ustrncmp(ibuf, "--", 2) == 0 |
117 | && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0 | |
118 | ) | |
baee9eee NM |
119 | break; |
120 | ||
c007c974 JH |
121 | for (ipos = ibuf ; *ipos != '\r' && *ipos != '\n' && *ipos != 0; ++ipos) |
122 | { | |
123 | if (*ipos == '=') /* skip padding */ | |
124 | { | |
baee9eee NM |
125 | ++bytestate; |
126 | continue; | |
c007c974 JH |
127 | } |
128 | if (mime_b64[*ipos] == 128) /* skip bad characters */ | |
129 | { | |
8523533c | 130 | mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64); |
baee9eee | 131 | continue; |
c007c974 JH |
132 | } |
133 | ||
baee9eee | 134 | /* simple state-machine */ |
c007c974 JH |
135 | switch((bytestate++) & 3) |
136 | { | |
baee9eee NM |
137 | case 0: |
138 | *opos = mime_b64[*ipos] << 2; | |
139 | break; | |
140 | case 1: | |
141 | *opos |= mime_b64[*ipos] >> 4; | |
142 | ++opos; | |
143 | *opos = mime_b64[*ipos] << 4; | |
144 | break; | |
145 | case 2: | |
146 | *opos |= mime_b64[*ipos] >> 2; | |
147 | ++opos; | |
148 | *opos = mime_b64[*ipos] << 6; | |
149 | break; | |
150 | case 3: | |
151 | *opos |= mime_b64[*ipos]; | |
152 | ++opos; | |
153 | break; | |
c007c974 JH |
154 | } /* switch */ |
155 | } /* for */ | |
156 | ||
baee9eee NM |
157 | /* something to write? */ |
158 | len = opos - obuf; | |
c007c974 JH |
159 | if (len > 0) |
160 | { | |
161 | if (fwrite(obuf, 1, len, out) != len) return -1; /* error */ | |
baee9eee NM |
162 | size += len; |
163 | /* copy incomplete last byte to start of obuf, where we continue */ | |
7156b1ef | 164 | if ((bytestate & 3) != 0) |
baee9eee NM |
165 | *obuf = *opos; |
166 | opos = obuf; | |
c007c974 JH |
167 | } |
168 | } /* while */ | |
baee9eee NM |
169 | |
170 | /* write out last byte if it was incomplete */ | |
c007c974 JH |
171 | if (bytestate & 3) |
172 | { | |
173 | if (fwrite(obuf, 1, 1, out) != 1) return -1; | |
174 | ++size; | |
175 | } | |
8e669ac1 | 176 | |
baee9eee NM |
177 | return size; |
178 | } | |
8e669ac1 | 179 | |
8e669ac1 | 180 | |
baee9eee | 181 | /* decode quoted-printable MIME part */ |
eb02738d PP |
182 | static ssize_t |
183 | mime_decode_qp(FILE* in, FILE* out, uschar* boundary) | |
baee9eee | 184 | { |
c007c974 JH |
185 | uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH]; |
186 | uschar *ipos, *opos; | |
187 | ssize_t len, size = 0; | |
baee9eee | 188 | |
c007c974 | 189 | while (fgets(CS ibuf, MIME_MAX_LINE_LENGTH, in) != NULL) |
baee9eee | 190 | { |
c007c974 JH |
191 | if (boundary != NULL |
192 | && Ustrncmp(ibuf, "--", 2) == 0 | |
193 | && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0 | |
194 | ) | |
195 | break; /* todo: check for missing boundary */ | |
8523533c | 196 | |
c007c974 JH |
197 | ipos = ibuf; |
198 | opos = obuf; | |
8e669ac1 | 199 | |
c007c974 JH |
200 | while (*ipos != 0) |
201 | { | |
202 | if (*ipos == '=') | |
203 | { | |
204 | int decode_qp_result; | |
205 | ||
206 | ipos = mime_decode_qp_char(ipos, &decode_qp_result); | |
207 | ||
208 | if (decode_qp_result == -2) | |
209 | { | |
210 | /* Error from decoder. ipos is unchanged. */ | |
211 | mime_set_anomaly(MIME_ANOMALY_BROKEN_QP); | |
212 | *opos = '='; | |
213 | ++opos; | |
214 | ++ipos; | |
215 | } | |
216 | else if (decode_qp_result == -1) | |
217 | break; | |
218 | else if (decode_qp_result >= 0) | |
219 | { | |
220 | *opos = decode_qp_result; | |
221 | ++opos; | |
222 | } | |
8523533c | 223 | } |
c007c974 JH |
224 | else |
225 | { | |
226 | *opos = *ipos; | |
227 | ++opos; | |
228 | ++ipos; | |
baee9eee NM |
229 | } |
230 | } | |
c007c974 JH |
231 | /* something to write? */ |
232 | len = opos - obuf; | |
233 | if (len > 0) | |
234 | { | |
235 | if (fwrite(obuf, 1, len, out) != len) return -1; /* error */ | |
236 | size += len; | |
baee9eee | 237 | } |
8523533c | 238 | } |
c007c974 | 239 | return size; |
8523533c TK |
240 | } |
241 | ||
242 | ||
f846c8f5 | 243 | static FILE * |
c007c974 JH |
244 | mime_get_decode_file(uschar *pname, uschar *fname) |
245 | { | |
246 | FILE *f = NULL; | |
247 | uschar *filename; | |
8e669ac1 | 248 | |
c007c974 | 249 | filename = (uschar *)malloc(2048); |
8e669ac1 | 250 | |
c007c974 JH |
251 | if (pname && fname) |
252 | { | |
253 | (void)string_format(filename, 2048, "%s/%s", pname, fname); | |
254 | f = modefopen(filename,"wb+",SPOOL_MODE); | |
8523533c | 255 | } |
c007c974 JH |
256 | else if (!pname) |
257 | f = modefopen(fname,"wb+",SPOOL_MODE); | |
258 | else if (!fname) | |
259 | { | |
260 | int file_nr = 0; | |
261 | int result = 0; | |
262 | ||
263 | /* must find first free sequential filename */ | |
264 | do | |
265 | { | |
266 | struct stat mystat; | |
267 | (void)string_format(filename, 2048, | |
268 | "%s/%s-%05u", pname, message_id, file_nr++); | |
269 | /* security break */ | |
270 | if (file_nr >= 1024) | |
271 | break; | |
272 | result = stat(CS filename, &mystat); | |
273 | } while(result != -1); | |
8523533c | 274 | |
c007c974 JH |
275 | f = modefopen(filename, "wb+", SPOOL_MODE); |
276 | } | |
8e669ac1 | 277 | |
c007c974 JH |
278 | /* set expansion variable */ |
279 | mime_decoded_filename = filename; | |
8e669ac1 | 280 | |
c007c974 | 281 | return f; |
8523533c TK |
282 | } |
283 | ||
284 | ||
c007c974 | 285 | int |
55414b25 | 286 | mime_decode(const uschar **listptr) |
c007c974 JH |
287 | { |
288 | int sep = 0; | |
55414b25 | 289 | const uschar *list = *listptr; |
c007c974 JH |
290 | uschar *option; |
291 | uschar option_buffer[1024]; | |
292 | uschar decode_path[1024]; | |
293 | FILE *decode_file = NULL; | |
294 | long f_pos = 0; | |
295 | ssize_t size_counter = 0; | |
296 | ssize_t (*decode_function)(FILE*, FILE*, uschar*); | |
297 | ||
298 | if (mime_stream == NULL) | |
299 | return FAIL; | |
300 | ||
301 | f_pos = ftell(mime_stream); | |
302 | ||
303 | /* build default decode path (will exist since MBOX must be spooled up) */ | |
304 | (void)string_format(decode_path,1024,"%s/scan/%s",spool_directory,message_id); | |
305 | ||
306 | /* try to find 1st option */ | |
307 | if ((option = string_nextinlist(&list, &sep, | |
308 | option_buffer, | |
309 | sizeof(option_buffer))) != NULL) | |
310 | { | |
311 | /* parse 1st option */ | |
312 | if ( (Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0) ) | |
313 | /* explicitly no decoding */ | |
8523533c | 314 | return FAIL; |
8e669ac1 | 315 | |
c007c974 JH |
316 | if (Ustrcmp(option,"default") == 0) |
317 | /* explicit default path + file names */ | |
318 | goto DEFAULT_PATH; | |
8e669ac1 | 319 | |
c007c974 JH |
320 | if (option[0] == '/') |
321 | { | |
322 | struct stat statbuf; | |
8e669ac1 | 323 | |
c007c974 | 324 | memset(&statbuf,0,sizeof(statbuf)); |
8e669ac1 | 325 | |
c007c974 JH |
326 | /* assume either path or path+file name */ |
327 | if ( (stat(CS option, &statbuf) == 0) && S_ISDIR(statbuf.st_mode) ) | |
328 | /* is directory, use it as decode_path */ | |
329 | decode_file = mime_get_decode_file(option, NULL); | |
8523533c | 330 | else |
c007c974 JH |
331 | /* does not exist or is a file, use as full file name */ |
332 | decode_file = mime_get_decode_file(NULL, option); | |
333 | } | |
baee9eee | 334 | else |
c007c974 JH |
335 | /* assume file name only, use default path */ |
336 | decode_file = mime_get_decode_file(decode_path, option); | |
337 | } | |
338 | else | |
339 | { | |
340 | /* no option? patch default path */ | |
341 | DEFAULT_PATH: | |
342 | decode_file = mime_get_decode_file(decode_path, NULL); | |
343 | } | |
8e669ac1 | 344 | |
c007c974 JH |
345 | if (!decode_file) |
346 | return DEFER; | |
8e669ac1 | 347 | |
c007c974 JH |
348 | /* decode according to mime type */ |
349 | decode_function = | |
350 | !mime_content_transfer_encoding | |
351 | ? mime_decode_asis /* no encoding, dump as-is */ | |
352 | : Ustrcmp(mime_content_transfer_encoding, "base64") == 0 | |
353 | ? mime_decode_base64 | |
354 | : Ustrcmp(mime_content_transfer_encoding, "quoted-printable") == 0 | |
355 | ? mime_decode_qp | |
356 | : mime_decode_asis; /* unknown encoding type, just dump as-is */ | |
8e669ac1 | 357 | |
c007c974 | 358 | size_counter = decode_function(mime_stream, decode_file, mime_current_boundary); |
baee9eee | 359 | |
c007c974 JH |
360 | clearerr(mime_stream); |
361 | fseek(mime_stream, f_pos, SEEK_SET); | |
8e669ac1 | 362 | |
c007c974 JH |
363 | if (fclose(decode_file) != 0 || size_counter < 0) |
364 | return DEFER; | |
8523533c | 365 | |
c007c974 JH |
366 | /* round up to the next KiB */ |
367 | mime_content_size = (size_counter + 1023) / 1024; | |
8e669ac1 | 368 | |
c007c974 JH |
369 | return OK; |
370 | } | |
8e669ac1 | 371 | |
f846c8f5 JH |
372 | |
373 | static int | |
c007c974 JH |
374 | mime_get_header(FILE *f, uschar *header) |
375 | { | |
376 | int c = EOF; | |
377 | int done = 0; | |
378 | int header_value_mode = 0; | |
379 | int header_open_brackets = 0; | |
380 | int num_copied = 0; | |
8e669ac1 | 381 | |
c007c974 JH |
382 | while(!done) |
383 | { | |
384 | if ((c = fgetc(f)) == EOF) break; | |
385 | ||
386 | /* always skip CRs */ | |
387 | if (c == '\r') continue; | |
388 | ||
389 | if (c == '\n') | |
390 | { | |
391 | if (num_copied > 0) | |
392 | { | |
393 | /* look if next char is '\t' or ' ' */ | |
394 | if ((c = fgetc(f)) == EOF) break; | |
395 | if ( (c == '\t') || (c == ' ') ) continue; | |
396 | (void)ungetc(c,f); | |
397 | } | |
398 | /* end of the header, terminate with ';' */ | |
399 | c = ';'; | |
400 | done = 1; | |
401 | } | |
8e669ac1 | 402 | |
c007c974 JH |
403 | /* skip control characters */ |
404 | if (c < 32) continue; | |
405 | ||
406 | if (header_value_mode) | |
407 | { | |
408 | /* --------- value mode ----------- */ | |
409 | /* skip leading whitespace */ | |
410 | if ( ((c == '\t') || (c == ' ')) && (header_value_mode == 1) ) | |
411 | continue; | |
8e669ac1 | 412 | |
8523533c TK |
413 | /* we have hit a non-whitespace char, start copying value data */ |
414 | header_value_mode = 2; | |
8e669ac1 | 415 | |
1bd0d12b JH |
416 | if (c == '"') /* flip "quoted" mode */ |
417 | header_value_mode = header_value_mode==2 ? 3 : 2; | |
8e669ac1 | 418 | |
1bd0d12b JH |
419 | /* leave value mode on unquoted ';' */ |
420 | if (header_value_mode == 2 && c == ';') { | |
8523533c TK |
421 | header_value_mode = 0; |
422 | }; | |
423 | /* -------------------------------- */ | |
424 | } | |
c007c974 JH |
425 | else |
426 | { | |
427 | /* -------- non-value mode -------- */ | |
428 | /* skip whitespace + tabs */ | |
429 | if ( (c == ' ') || (c == '\t') ) | |
430 | continue; | |
431 | if (c == '\\') | |
432 | { | |
433 | /* quote next char. can be used | |
434 | to escape brackets. */ | |
435 | if ((c = fgetc(f)) == EOF) break; | |
8523533c | 436 | } |
c007c974 JH |
437 | else if (c == '(') |
438 | { | |
439 | header_open_brackets++; | |
440 | continue; | |
8523533c | 441 | } |
c007c974 JH |
442 | else if ((c == ')') && header_open_brackets) |
443 | { | |
444 | header_open_brackets--; | |
445 | continue; | |
8523533c | 446 | } |
c007c974 JH |
447 | else if ( (c == '=') && !header_open_brackets ) /* enter value mode */ |
448 | header_value_mode = 1; | |
8e669ac1 | 449 | |
c007c974 JH |
450 | /* skip chars while we are in a comment */ |
451 | if (header_open_brackets > 0) | |
452 | continue; | |
453 | /* -------------------------------- */ | |
454 | } | |
8e669ac1 | 455 | |
c007c974 JH |
456 | /* copy the char to the buffer */ |
457 | header[num_copied++] = (uschar)c; | |
8e669ac1 | 458 | |
c007c974 JH |
459 | /* break if header buffer is full */ |
460 | if (num_copied > MIME_MAX_HEADER_SIZE-1) | |
461 | done = 1; | |
462 | } | |
8523533c | 463 | |
c007c974 JH |
464 | if ((num_copied > 0) && (header[num_copied-1] != ';')) |
465 | header[num_copied-1] = ';'; | |
8523533c | 466 | |
c007c974 JH |
467 | /* 0-terminate */ |
468 | header[num_copied] = '\0'; | |
8e669ac1 | 469 | |
c007c974 JH |
470 | /* return 0 for EOF or empty line */ |
471 | if ((c == EOF) || (num_copied == 1)) | |
472 | return 0; | |
473 | else | |
474 | return 1; | |
8523533c TK |
475 | } |
476 | ||
477 | ||
f846c8f5 JH |
478 | static void |
479 | mime_vars_reset(void) | |
480 | { | |
481 | mime_anomaly_level = 0; | |
482 | mime_anomaly_text = NULL; | |
483 | mime_boundary = NULL; | |
484 | mime_charset = NULL; | |
485 | mime_decoded_filename = NULL; | |
486 | mime_filename = NULL; | |
487 | mime_content_description = NULL; | |
488 | mime_content_disposition = NULL; | |
489 | mime_content_id = NULL; | |
490 | mime_content_transfer_encoding = NULL; | |
491 | mime_content_type = NULL; | |
492 | mime_is_multipart = 0; | |
493 | mime_content_size = 0; | |
494 | } | |
495 | ||
496 | ||
497 | /* Grab a parameter value, dealing with quoting. | |
498 | ||
499 | Arguments: | |
500 | str Input string. Updated on return to point to terminating ; or NUL | |
501 | ||
502 | Return: | |
503 | Allocated string with parameter value | |
504 | */ | |
505 | static uschar * | |
506 | mime_param_val(uschar ** sp) | |
507 | { | |
508 | uschar * s = *sp; | |
509 | uschar * val = NULL; | |
510 | int size = 0, ptr = 0; | |
511 | ||
512 | /* debug_printf(" considering paramval '%s'\n", s); */ | |
513 | ||
514 | while (*s && *s != ';') /* ; terminates */ | |
515 | if (*s == '"') | |
516 | { | |
517 | s++; /* skip opening " */ | |
518 | while (*s && *s != '"') /* " protects ; */ | |
519 | val = string_cat(val, &size, &ptr, s++, 1); | |
520 | if (*s) s++; /* skip closing " */ | |
521 | } | |
522 | else | |
523 | val = string_cat(val, &size, &ptr, s++, 1); | |
524 | if (val) val[ptr] = '\0'; | |
525 | *sp = s; | |
526 | return val; | |
527 | } | |
528 | ||
529 | static uschar * | |
530 | mime_next_semicolon(uschar * s) | |
531 | { | |
532 | while (*s && *s != ';') /* ; terminates */ | |
533 | if (*s == '"') | |
534 | { | |
535 | s++; /* skip opening " */ | |
536 | while (*s && *s != '"') /* " protects ; */ | |
537 | s++; | |
538 | if (*s) s++; /* skip closing " */ | |
539 | } | |
540 | else | |
541 | s++; | |
542 | return s; | |
543 | } | |
544 | ||
545 | ||
627d1a1b JH |
546 | static uschar * |
547 | rfc2231_to_2047(const uschar * fname, const uschar * charset, int * len) | |
548 | { | |
549 | int size = 0, ptr = 0; | |
550 | uschar * val = string_cat(NULL, &size, &ptr, US"=?", 2); | |
551 | uschar c; | |
552 | ||
622dbd6a JH |
553 | if (charset) |
554 | val = string_cat(val, &size, &ptr, charset, Ustrlen(charset)); | |
627d1a1b JH |
555 | val = string_cat(val, &size, &ptr, US"?Q?", 3); |
556 | ||
557 | while ((c = *fname)) | |
558 | if (c == '%' && isxdigit(fname[1]) && isxdigit(fname[2])) | |
559 | { | |
560 | val = string_cat(val, &size, &ptr, US"=", 1); | |
561 | val = string_cat(val, &size, &ptr, ++fname, 2); | |
562 | fname += 2; | |
563 | } | |
564 | else | |
565 | val = string_cat(val, &size, &ptr, fname++, 1); | |
566 | ||
567 | val = string_cat(val, &size, &ptr, US"?=", 2); | |
568 | val[*len = ptr] = '\0'; | |
569 | return val; | |
570 | } | |
571 | ||
572 | ||
c007c974 JH |
573 | int |
574 | mime_acl_check(uschar *acl, FILE *f, struct mime_boundary_context *context, | |
f846c8f5 | 575 | uschar **user_msgptr, uschar **log_msgptr) |
c007c974 JH |
576 | { |
577 | int rc = OK; | |
f846c8f5 | 578 | uschar * header = NULL; |
c007c974 JH |
579 | struct mime_boundary_context nested_context; |
580 | ||
581 | /* reserve a line buffer to work in */ | |
f846c8f5 | 582 | header = store_get(MIME_MAX_HEADER_SIZE+1); |
c007c974 JH |
583 | |
584 | /* Not actually used at the moment, but will be vital to fixing | |
585 | * some RFC 2046 nonconformance later... */ | |
586 | nested_context.parent = context; | |
587 | ||
588 | /* loop through parts */ | |
589 | while(1) | |
590 | { | |
591 | /* reset all per-part mime variables */ | |
f846c8f5 JH |
592 | mime_vars_reset(); |
593 | ||
594 | /* If boundary is null, we assume that *f is positioned on the start of | |
595 | headers (for example, at the very beginning of a message. If a boundary is | |
596 | given, we must first advance to it to reach the start of the next header | |
597 | block. */ | |
c007c974 JH |
598 | |
599 | /* NOTE -- there's an error here -- RFC2046 specifically says to | |
600 | * check for outer boundaries. This code doesn't do that, and | |
601 | * I haven't fixed this. | |
602 | * | |
603 | * (I have moved partway towards adding support, however, by adding | |
604 | * a "parent" field to my new boundary-context structure.) | |
605 | */ | |
f846c8f5 | 606 | if (context) for (;;) |
c007c974 | 607 | { |
f846c8f5 | 608 | if (!fgets(CS header, MIME_MAX_HEADER_SIZE, f)) |
c007c974 | 609 | { |
f846c8f5 | 610 | /* Hit EOF or read error. Ugh. */ |
622dbd6a | 611 | DEBUG(D_acl) debug_printf("MIME: Hit EOF ...\n"); |
f846c8f5 JH |
612 | return rc; |
613 | } | |
5c6cf6a0 | 614 | |
f846c8f5 JH |
615 | /* boundary line must start with 2 dashes */ |
616 | if ( Ustrncmp(header, "--", 2) == 0 | |
617 | && Ustrncmp(header+2, context->boundary, Ustrlen(context->boundary)) == 0 | |
618 | ) | |
619 | { /* found boundary */ | |
620 | if (Ustrncmp((header+2+Ustrlen(context->boundary)), "--", 2) == 0) | |
621 | { | |
622 | /* END boundary found */ | |
622dbd6a | 623 | DEBUG(D_acl) debug_printf("MIME: End boundary found %s\n", |
f846c8f5 JH |
624 | context->boundary); |
625 | return rc; | |
c007c974 | 626 | } |
f846c8f5 | 627 | |
622dbd6a | 628 | DEBUG(D_acl) debug_printf("MIME: Next part with boundary %s\n", |
f846c8f5 JH |
629 | context->boundary); |
630 | break; | |
8523533c | 631 | } |
c007c974 | 632 | } |
8e669ac1 | 633 | |
c007c974 | 634 | /* parse headers, set up expansion variables */ |
5c6cf6a0 | 635 | while (mime_get_header(f, header)) |
c007c974 | 636 | { |
f846c8f5 JH |
637 | struct mime_header * mh; |
638 | ||
639 | /* look for interesting headers */ | |
640 | for (mh = mime_header_list; | |
641 | mh < mime_header_list + mime_header_list_size; | |
642 | mh++) if (strncmpic(mh->name, header, mh->namelen) == 0) | |
643 | { | |
f846c8f5 JH |
644 | uschar * p = header + mh->namelen; |
645 | uschar * q; | |
c007c974 | 646 | |
f846c8f5 JH |
647 | /* grab the value (normalize to lower case) |
648 | and copy to its corresponding expansion variable */ | |
649 | ||
650 | for (q = p; *q != ';' && *q; q++) ; | |
651 | *mh->value = string_copynlc(p, q-p); | |
622dbd6a | 652 | DEBUG(D_acl) debug_printf("MIME: found %s header, value is '%s'\n", |
f846c8f5 JH |
653 | mh->name, *mh->value); |
654 | ||
655 | if (*(p = q)) p++; /* jump past the ; */ | |
656 | ||
657 | { | |
658 | uschar * mime_fname = NULL; | |
659 | uschar * mime_fname_rfc2231 = NULL; | |
660 | uschar * mime_filename_charset = NULL; | |
661 | BOOL decoding_failed = FALSE; | |
c007c974 | 662 | |
5c6cf6a0 JH |
663 | /* grab all param=value tags on the remaining line, |
664 | check if they are interesting */ | |
f846c8f5 | 665 | |
5c6cf6a0 | 666 | while (*p) |
c007c974 JH |
667 | { |
668 | mime_parameter * mp; | |
f846c8f5 | 669 | |
622dbd6a | 670 | DEBUG(D_acl) debug_printf("MIME: considering paramlist '%s'\n", p); |
f846c8f5 JH |
671 | |
672 | if ( !mime_filename | |
fc362fc5 JH |
673 | && strncmpic(CUS"content-disposition:", header, 20) == 0 |
674 | && strncmpic(CUS"filename*", p, 9) == 0 | |
f846c8f5 JH |
675 | ) |
676 | { /* RFC 2231 filename */ | |
677 | uschar * q; | |
678 | ||
679 | /* find value of the filename */ | |
680 | p += 9; | |
681 | while(*p != '=' && *p) p++; | |
682 | if (*p) p++; /* p is filename or NUL */ | |
683 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
684 | ||
685 | if (q && *q) | |
c007c974 | 686 | { |
f846c8f5 JH |
687 | uschar * temp_string, * err_msg; |
688 | int slen; | |
4fd5d2bf | 689 | |
f846c8f5 JH |
690 | /* build up an un-decoded filename over successive |
691 | filename*= parameters (for use when 2047 decode fails) */ | |
692 | ||
693 | mime_fname_rfc2231 = string_sprintf("%#s%s", | |
694 | mime_fname_rfc2231, q); | |
695 | ||
696 | if (!decoding_failed) | |
697 | { | |
698 | int size; | |
699 | if (!mime_filename_charset) | |
4fd5d2bf | 700 | { |
f846c8f5 JH |
701 | uschar * s = q; |
702 | ||
703 | /* look for a ' in the "filename" */ | |
622dbd6a | 704 | while(*s != '\'' && *s) s++; /* s is 1st ' or NUL */ |
f846c8f5 JH |
705 | |
706 | if ((size = s-q) > 0) | |
f846c8f5 | 707 | mime_filename_charset = string_copyn(q, size); |
f846c8f5 | 708 | |
622dbd6a JH |
709 | if (*(p = s)) p++; |
710 | while(*p == '\'') p++; /* p is after 2nd ' */ | |
4fd5d2bf JH |
711 | } |
712 | else | |
f846c8f5 | 713 | p = q; |
5c6cf6a0 | 714 | |
622dbd6a JH |
715 | DEBUG(D_acl) debug_printf("MIME: charset %s fname '%s'\n", |
716 | mime_filename_charset ? mime_filename_charset : US"<NULL>", p); | |
717 | ||
627d1a1b | 718 | temp_string = rfc2231_to_2047(p, mime_filename_charset, &slen); |
622dbd6a JH |
719 | DEBUG(D_acl) debug_printf("MIME: 2047-name %s\n", temp_string); |
720 | ||
721 | temp_string = rfc2047_decode(temp_string, FALSE, NULL, ' ', | |
f846c8f5 | 722 | NULL, &err_msg); |
622dbd6a JH |
723 | DEBUG(D_acl) debug_printf("MIME: plain-name %s\n", temp_string); |
724 | ||
f846c8f5 JH |
725 | size = Ustrlen(temp_string); |
726 | ||
727 | if (size == slen) | |
728 | decoding_failed = TRUE; | |
729 | else | |
730 | /* build up a decoded filename over successive | |
731 | filename*= parameters */ | |
732 | ||
733 | mime_filename = mime_fname = mime_fname | |
734 | ? string_sprintf("%s%s", mime_fname, temp_string) | |
735 | : temp_string; | |
93cad488 | 736 | } |
f846c8f5 | 737 | } |
5c6cf6a0 | 738 | } |
f846c8f5 | 739 | |
e7c25d5b | 740 | else |
f846c8f5 JH |
741 | /* look for interesting parameters */ |
742 | for (mp = mime_parameter_list; | |
743 | mp < mime_parameter_list + nelem(mime_parameter_list); | |
744 | mp++ | |
745 | ) if (strncmpic(mp->name, p, mp->namelen) == 0) | |
746 | { | |
747 | uschar * q; | |
748 | uschar * dummy_errstr; | |
749 | ||
750 | /* grab the value and copy to its expansion variable */ | |
751 | p += mp->namelen; | |
752 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
753 | ||
754 | *mp->value = q && *q | |
755 | ? rfc2047_decode(q, check_rfc2047_length, NULL, 32, NULL, | |
756 | &dummy_errstr) | |
757 | : NULL; | |
758 | DEBUG(D_acl) debug_printf( | |
622dbd6a | 759 | "MIME: found %s parameter in %s header, value '%s'\n", |
f846c8f5 JH |
760 | mp->name, mh->name, *mp->value); |
761 | ||
762 | break; /* done matching param names */ | |
763 | } | |
764 | ||
765 | ||
766 | /* There is something, but not one of our interesting parameters. | |
767 | Advance past the next semicolon */ | |
768 | p = mime_next_semicolon(p); | |
769 | if (*p) p++; | |
770 | } /* param scan on line */ | |
771 | ||
fc362fc5 | 772 | if (strncmpic(CUS"content-disposition:", header, 20) == 0) |
f846c8f5 JH |
773 | { |
774 | if (decoding_failed) mime_filename = mime_fname_rfc2231; | |
775 | ||
776 | DEBUG(D_acl) debug_printf( | |
622dbd6a | 777 | "MIME: found %s parameter in %s header, value is '%s'\n", |
f846c8f5 JH |
778 | "filename", mh->name, mime_filename); |
779 | } | |
c007c974 JH |
780 | } |
781 | } | |
f846c8f5 | 782 | } |
8e669ac1 | 783 | |
c007c974 | 784 | /* set additional flag variables (easier access) */ |
f846c8f5 JH |
785 | if ( mime_content_type |
786 | && Ustrncmp(mime_content_type,"multipart",9) == 0 | |
787 | ) | |
c007c974 | 788 | mime_is_multipart = 1; |
8e669ac1 | 789 | |
c007c974 JH |
790 | /* Make a copy of the boundary pointer. |
791 | Required since mime_boundary is global | |
792 | and can be overwritten further down in recursion */ | |
793 | nested_context.boundary = mime_boundary; | |
8e669ac1 | 794 | |
c007c974 JH |
795 | /* raise global counter */ |
796 | mime_part_count++; | |
8523533c | 797 | |
c007c974 JH |
798 | /* copy current file handle to global variable */ |
799 | mime_stream = f; | |
800 | mime_current_boundary = context ? context->boundary : 0; | |
8e669ac1 | 801 | |
c007c974 JH |
802 | /* Note the context */ |
803 | mime_is_coverletter = !(context && context->context == MBC_ATTACHMENT); | |
8e669ac1 | 804 | |
c007c974 JH |
805 | /* call ACL handling function */ |
806 | rc = acl_check(ACL_WHERE_MIME, NULL, acl, user_msgptr, log_msgptr); | |
8e669ac1 | 807 | |
c007c974 JH |
808 | mime_stream = NULL; |
809 | mime_current_boundary = NULL; | |
810 | ||
811 | if (rc != OK) break; | |
8e669ac1 | 812 | |
c007c974 JH |
813 | /* If we have a multipart entity and a boundary, go recursive */ |
814 | if ( (mime_content_type != NULL) && | |
815 | (nested_context.boundary != NULL) && | |
816 | (Ustrncmp(mime_content_type,"multipart",9) == 0) ) | |
817 | { | |
622dbd6a JH |
818 | DEBUG(D_acl) |
819 | debug_printf("MIME: Entering multipart recursion, boundary '%s'\n", | |
820 | nested_context.boundary); | |
c007c974 JH |
821 | |
822 | nested_context.context = | |
823 | context && context->context == MBC_ATTACHMENT | |
824 | ? MBC_ATTACHMENT | |
825 | : Ustrcmp(mime_content_type,"multipart/alternative") == 0 | |
826 | || Ustrcmp(mime_content_type,"multipart/related") == 0 | |
827 | ? MBC_COVERLETTER_ALL | |
828 | : MBC_COVERLETTER_ONESHOT; | |
829 | ||
830 | rc = mime_acl_check(acl, f, &nested_context, user_msgptr, log_msgptr); | |
831 | if (rc != OK) break; | |
8523533c | 832 | } |
c007c974 JH |
833 | else if ( (mime_content_type != NULL) && |
834 | (Ustrncmp(mime_content_type,"message/rfc822",14) == 0) ) | |
835 | { | |
55414b25 | 836 | const uschar *rfc822name = NULL; |
c007c974 JH |
837 | uschar filename[2048]; |
838 | int file_nr = 0; | |
839 | int result = 0; | |
8e669ac1 | 840 | |
c007c974 JH |
841 | /* must find first free sequential filename */ |
842 | do | |
843 | { | |
844 | struct stat mystat; | |
845 | (void)string_format(filename, 2048, | |
846 | "%s/scan/%s/__rfc822_%05u", spool_directory, message_id, file_nr++); | |
847 | /* security break */ | |
848 | if (file_nr >= 128) | |
849 | goto NO_RFC822; | |
850 | result = stat(CS filename,&mystat); | |
851 | } while (result != -1); | |
852 | ||
853 | rfc822name = filename; | |
854 | ||
855 | /* decode RFC822 attachment */ | |
856 | mime_decoded_filename = NULL; | |
857 | mime_stream = f; | |
858 | mime_current_boundary = context ? context->boundary : NULL; | |
859 | mime_decode(&rfc822name); | |
860 | mime_stream = NULL; | |
861 | mime_current_boundary = NULL; | |
862 | if (!mime_decoded_filename) /* decoding failed */ | |
863 | { | |
864 | log_write(0, LOG_MAIN, | |
865 | "mime_regex acl condition warning - could not decode RFC822 MIME part to file."); | |
f846c8f5 JH |
866 | rc = DEFER; |
867 | goto out; | |
c007c974 JH |
868 | } |
869 | mime_decoded_filename = NULL; | |
870 | } | |
8523533c | 871 | |
c007c974 JH |
872 | NO_RFC822: |
873 | /* If the boundary of this instance is NULL, we are finished here */ | |
f846c8f5 | 874 | if (!context) break; |
8e669ac1 | 875 | |
c007c974 JH |
876 | if (context->context == MBC_COVERLETTER_ONESHOT) |
877 | context->context = MBC_ATTACHMENT; | |
878 | } | |
8523533c | 879 | |
f846c8f5 JH |
880 | out: |
881 | mime_vars_reset(); | |
c007c974 | 882 | return rc; |
8523533c TK |
883 | } |
884 | ||
c007c974 JH |
885 | #endif /*WITH_CONTENT_SCAN*/ |
886 | ||
887 | /* vi: sw ai sw=2 | |
888 | */ |