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; | |
f2cb6292 JH |
15 | |
16 | static mime_header mime_header_list[] = { | |
17 | { US"content-type:", 13, &mime_content_type }, | |
18 | { US"content-disposition:", 20, &mime_content_disposition }, | |
19 | { US"content-transfer-encoding:", 26, &mime_content_transfer_encoding }, | |
20 | { US"content-id:", 11, &mime_content_id }, | |
21 | { US"content-description:", 20, &mime_content_description } | |
22 | }; | |
23 | ||
24 | static int mime_header_list_size = nelem(mime_header_list); | |
3c51463e JH |
25 | |
26 | static mime_parameter mime_parameter_list[] = { | |
27 | { US"name=", 5, &mime_filename }, | |
28 | { US"filename=", 9, &mime_filename }, | |
29 | { US"charset=", 8, &mime_charset }, | |
30 | { US"boundary=", 9, &mime_boundary } | |
31 | }; | |
32 | ||
8523533c TK |
33 | |
34 | /************************************************* | |
35 | * set MIME anomaly level + text * | |
36 | *************************************************/ | |
37 | ||
38 | /* Small wrapper to set the two expandables which | |
39 | give info on detected "problems" in MIME | |
f4d091fb | 40 | encodings. Indexes are defined in mime.h. */ |
8523533c | 41 | |
f4d091fb JH |
42 | void |
43 | mime_set_anomaly(int idx) | |
c007c974 | 44 | { |
f4d091fb JH |
45 | struct anom { |
46 | int level; | |
47 | const uschar * text; | |
48 | } anom[] = { {1, CUS"Broken Quoted-Printable encoding detected"}, | |
49 | {2, CUS"Broken BASE64 encoding detected"} }; | |
50 | ||
51 | mime_anomaly_level = anom[idx].level; | |
52 | mime_anomaly_text = anom[idx].text; | |
f7b63901 | 53 | } |
8523533c TK |
54 | |
55 | ||
56 | /************************************************* | |
57 | * decode quoted-printable chars * | |
58 | *************************************************/ | |
59 | ||
60 | /* gets called when we hit a = | |
61 | returns: new pointer position | |
62 | result code in c: | |
63 | -2 - decode error | |
64 | -1 - soft line break, no char | |
65 | 0-255 - char to write | |
66 | */ | |
67 | ||
f846c8f5 | 68 | static uschar * |
c007c974 JH |
69 | mime_decode_qp_char(uschar *qp_p, int *c) |
70 | { | |
71 | uschar *initial_pos = qp_p; | |
72 | ||
73 | /* advance one char */ | |
74 | qp_p++; | |
75 | ||
76 | /* Check for two hex digits and decode them */ | |
77 | if (isxdigit(*qp_p) && isxdigit(qp_p[1])) | |
78 | { | |
79 | /* Do hex conversion */ | |
80 | *c = (isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10) <<4; | |
81 | qp_p++; | |
82 | *c |= isdigit(*qp_p) ? *qp_p - '0' : toupper(*qp_p) - 'A' + 10; | |
83 | return qp_p + 1; | |
84 | } | |
8e669ac1 | 85 | |
c007c974 JH |
86 | /* tab or whitespace may follow just ignore it if it precedes \n */ |
87 | while (*qp_p == '\t' || *qp_p == ' ' || *qp_p == '\r') | |
8523533c | 88 | qp_p++; |
8e669ac1 | 89 | |
c007c974 JH |
90 | if (*qp_p == '\n') /* hit soft line break */ |
91 | { | |
92 | *c = -1; | |
93 | return qp_p; | |
94 | } | |
95 | ||
96 | /* illegal char here */ | |
97 | *c = -2; | |
98 | return initial_pos; | |
8523533c TK |
99 | } |
100 | ||
101 | ||
baee9eee | 102 | /* just dump MIME part without any decoding */ |
eb02738d PP |
103 | static ssize_t |
104 | mime_decode_asis(FILE* in, FILE* out, uschar* boundary) | |
baee9eee | 105 | { |
eb02738d | 106 | ssize_t len, size = 0; |
baee9eee | 107 | uschar buffer[MIME_MAX_LINE_LENGTH]; |
d203e649 | 108 | |
c007c974 JH |
109 | while(fgets(CS buffer, MIME_MAX_LINE_LENGTH, mime_stream) != NULL) |
110 | { | |
baee9eee | 111 | if (boundary != NULL |
c007c974 JH |
112 | && Ustrncmp(buffer, "--", 2) == 0 |
113 | && Ustrncmp((buffer+2), boundary, Ustrlen(boundary)) == 0 | |
114 | ) | |
baee9eee NM |
115 | break; |
116 | ||
117 | len = Ustrlen(buffer); | |
118 | if (fwrite(buffer, 1, (size_t)len, out) < len) | |
119 | return -1; | |
120 | size += len; | |
c007c974 | 121 | } /* while */ |
baee9eee NM |
122 | return size; |
123 | } | |
84330b7b | 124 | |
8523533c | 125 | |
8e669ac1 | 126 | |
baee9eee | 127 | /* decode quoted-printable MIME part */ |
eb02738d PP |
128 | static ssize_t |
129 | mime_decode_qp(FILE* in, FILE* out, uschar* boundary) | |
baee9eee | 130 | { |
c007c974 JH |
131 | uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH]; |
132 | uschar *ipos, *opos; | |
133 | ssize_t len, size = 0; | |
baee9eee | 134 | |
c007c974 | 135 | while (fgets(CS ibuf, MIME_MAX_LINE_LENGTH, in) != NULL) |
baee9eee | 136 | { |
c007c974 JH |
137 | if (boundary != NULL |
138 | && Ustrncmp(ibuf, "--", 2) == 0 | |
139 | && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0 | |
140 | ) | |
141 | break; /* todo: check for missing boundary */ | |
8523533c | 142 | |
c007c974 JH |
143 | ipos = ibuf; |
144 | opos = obuf; | |
8e669ac1 | 145 | |
c007c974 JH |
146 | while (*ipos != 0) |
147 | { | |
148 | if (*ipos == '=') | |
149 | { | |
150 | int decode_qp_result; | |
151 | ||
152 | ipos = mime_decode_qp_char(ipos, &decode_qp_result); | |
153 | ||
154 | if (decode_qp_result == -2) | |
155 | { | |
156 | /* Error from decoder. ipos is unchanged. */ | |
157 | mime_set_anomaly(MIME_ANOMALY_BROKEN_QP); | |
158 | *opos = '='; | |
159 | ++opos; | |
160 | ++ipos; | |
161 | } | |
162 | else if (decode_qp_result == -1) | |
163 | break; | |
164 | else if (decode_qp_result >= 0) | |
165 | { | |
166 | *opos = decode_qp_result; | |
167 | ++opos; | |
168 | } | |
8523533c | 169 | } |
c007c974 JH |
170 | else |
171 | { | |
172 | *opos = *ipos; | |
173 | ++opos; | |
174 | ++ipos; | |
baee9eee NM |
175 | } |
176 | } | |
c007c974 JH |
177 | /* something to write? */ |
178 | len = opos - obuf; | |
179 | if (len > 0) | |
180 | { | |
181 | if (fwrite(obuf, 1, len, out) != len) return -1; /* error */ | |
182 | size += len; | |
baee9eee | 183 | } |
8523533c | 184 | } |
c007c974 | 185 | return size; |
8523533c TK |
186 | } |
187 | ||
188 | ||
f846c8f5 | 189 | static FILE * |
c007c974 JH |
190 | mime_get_decode_file(uschar *pname, uschar *fname) |
191 | { | |
192 | FILE *f = NULL; | |
193 | uschar *filename; | |
8e669ac1 | 194 | |
c007c974 | 195 | filename = (uschar *)malloc(2048); |
8e669ac1 | 196 | |
c007c974 JH |
197 | if (pname && fname) |
198 | { | |
199 | (void)string_format(filename, 2048, "%s/%s", pname, fname); | |
200 | f = modefopen(filename,"wb+",SPOOL_MODE); | |
8523533c | 201 | } |
c007c974 JH |
202 | else if (!pname) |
203 | f = modefopen(fname,"wb+",SPOOL_MODE); | |
204 | else if (!fname) | |
205 | { | |
206 | int file_nr = 0; | |
207 | int result = 0; | |
208 | ||
209 | /* must find first free sequential filename */ | |
210 | do | |
211 | { | |
212 | struct stat mystat; | |
213 | (void)string_format(filename, 2048, | |
214 | "%s/%s-%05u", pname, message_id, file_nr++); | |
215 | /* security break */ | |
216 | if (file_nr >= 1024) | |
217 | break; | |
218 | result = stat(CS filename, &mystat); | |
219 | } while(result != -1); | |
8523533c | 220 | |
c007c974 JH |
221 | f = modefopen(filename, "wb+", SPOOL_MODE); |
222 | } | |
8e669ac1 | 223 | |
c007c974 JH |
224 | /* set expansion variable */ |
225 | mime_decoded_filename = filename; | |
8e669ac1 | 226 | |
c007c974 | 227 | return f; |
8523533c TK |
228 | } |
229 | ||
230 | ||
c007c974 | 231 | int |
55414b25 | 232 | mime_decode(const uschar **listptr) |
c007c974 JH |
233 | { |
234 | int sep = 0; | |
55414b25 | 235 | const uschar *list = *listptr; |
c007c974 JH |
236 | uschar *option; |
237 | uschar option_buffer[1024]; | |
238 | uschar decode_path[1024]; | |
239 | FILE *decode_file = NULL; | |
240 | long f_pos = 0; | |
241 | ssize_t size_counter = 0; | |
242 | ssize_t (*decode_function)(FILE*, FILE*, uschar*); | |
243 | ||
244 | if (mime_stream == NULL) | |
245 | return FAIL; | |
246 | ||
247 | f_pos = ftell(mime_stream); | |
248 | ||
249 | /* build default decode path (will exist since MBOX must be spooled up) */ | |
250 | (void)string_format(decode_path,1024,"%s/scan/%s",spool_directory,message_id); | |
251 | ||
252 | /* try to find 1st option */ | |
253 | if ((option = string_nextinlist(&list, &sep, | |
254 | option_buffer, | |
255 | sizeof(option_buffer))) != NULL) | |
256 | { | |
257 | /* parse 1st option */ | |
258 | if ( (Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0) ) | |
259 | /* explicitly no decoding */ | |
8523533c | 260 | return FAIL; |
8e669ac1 | 261 | |
c007c974 JH |
262 | if (Ustrcmp(option,"default") == 0) |
263 | /* explicit default path + file names */ | |
264 | goto DEFAULT_PATH; | |
8e669ac1 | 265 | |
c007c974 JH |
266 | if (option[0] == '/') |
267 | { | |
268 | struct stat statbuf; | |
8e669ac1 | 269 | |
c007c974 | 270 | memset(&statbuf,0,sizeof(statbuf)); |
8e669ac1 | 271 | |
c007c974 JH |
272 | /* assume either path or path+file name */ |
273 | if ( (stat(CS option, &statbuf) == 0) && S_ISDIR(statbuf.st_mode) ) | |
274 | /* is directory, use it as decode_path */ | |
275 | decode_file = mime_get_decode_file(option, NULL); | |
8523533c | 276 | else |
c007c974 JH |
277 | /* does not exist or is a file, use as full file name */ |
278 | decode_file = mime_get_decode_file(NULL, option); | |
279 | } | |
baee9eee | 280 | else |
c007c974 JH |
281 | /* assume file name only, use default path */ |
282 | decode_file = mime_get_decode_file(decode_path, option); | |
283 | } | |
284 | else | |
285 | { | |
286 | /* no option? patch default path */ | |
287 | DEFAULT_PATH: | |
288 | decode_file = mime_get_decode_file(decode_path, NULL); | |
289 | } | |
8e669ac1 | 290 | |
c007c974 JH |
291 | if (!decode_file) |
292 | return DEFER; | |
8e669ac1 | 293 | |
c007c974 JH |
294 | /* decode according to mime type */ |
295 | decode_function = | |
296 | !mime_content_transfer_encoding | |
297 | ? mime_decode_asis /* no encoding, dump as-is */ | |
298 | : Ustrcmp(mime_content_transfer_encoding, "base64") == 0 | |
299 | ? mime_decode_base64 | |
300 | : Ustrcmp(mime_content_transfer_encoding, "quoted-printable") == 0 | |
301 | ? mime_decode_qp | |
302 | : mime_decode_asis; /* unknown encoding type, just dump as-is */ | |
8e669ac1 | 303 | |
c007c974 | 304 | size_counter = decode_function(mime_stream, decode_file, mime_current_boundary); |
baee9eee | 305 | |
c007c974 JH |
306 | clearerr(mime_stream); |
307 | fseek(mime_stream, f_pos, SEEK_SET); | |
8e669ac1 | 308 | |
c007c974 JH |
309 | if (fclose(decode_file) != 0 || size_counter < 0) |
310 | return DEFER; | |
8523533c | 311 | |
c007c974 JH |
312 | /* round up to the next KiB */ |
313 | mime_content_size = (size_counter + 1023) / 1024; | |
8e669ac1 | 314 | |
c007c974 JH |
315 | return OK; |
316 | } | |
8e669ac1 | 317 | |
f846c8f5 JH |
318 | |
319 | static int | |
c007c974 JH |
320 | mime_get_header(FILE *f, uschar *header) |
321 | { | |
322 | int c = EOF; | |
323 | int done = 0; | |
324 | int header_value_mode = 0; | |
325 | int header_open_brackets = 0; | |
326 | int num_copied = 0; | |
8e669ac1 | 327 | |
c007c974 JH |
328 | while(!done) |
329 | { | |
330 | if ((c = fgetc(f)) == EOF) break; | |
331 | ||
332 | /* always skip CRs */ | |
333 | if (c == '\r') continue; | |
334 | ||
335 | if (c == '\n') | |
336 | { | |
337 | if (num_copied > 0) | |
338 | { | |
339 | /* look if next char is '\t' or ' ' */ | |
340 | if ((c = fgetc(f)) == EOF) break; | |
341 | if ( (c == '\t') || (c == ' ') ) continue; | |
342 | (void)ungetc(c,f); | |
343 | } | |
344 | /* end of the header, terminate with ';' */ | |
345 | c = ';'; | |
346 | done = 1; | |
347 | } | |
8e669ac1 | 348 | |
c007c974 JH |
349 | /* skip control characters */ |
350 | if (c < 32) continue; | |
351 | ||
352 | if (header_value_mode) | |
353 | { | |
354 | /* --------- value mode ----------- */ | |
355 | /* skip leading whitespace */ | |
356 | if ( ((c == '\t') || (c == ' ')) && (header_value_mode == 1) ) | |
357 | continue; | |
8e669ac1 | 358 | |
8523533c TK |
359 | /* we have hit a non-whitespace char, start copying value data */ |
360 | header_value_mode = 2; | |
8e669ac1 | 361 | |
1bd0d12b JH |
362 | if (c == '"') /* flip "quoted" mode */ |
363 | header_value_mode = header_value_mode==2 ? 3 : 2; | |
8e669ac1 | 364 | |
1bd0d12b JH |
365 | /* leave value mode on unquoted ';' */ |
366 | if (header_value_mode == 2 && c == ';') { | |
8523533c TK |
367 | header_value_mode = 0; |
368 | }; | |
369 | /* -------------------------------- */ | |
370 | } | |
c007c974 JH |
371 | else |
372 | { | |
373 | /* -------- non-value mode -------- */ | |
374 | /* skip whitespace + tabs */ | |
375 | if ( (c == ' ') || (c == '\t') ) | |
376 | continue; | |
377 | if (c == '\\') | |
378 | { | |
379 | /* quote next char. can be used | |
380 | to escape brackets. */ | |
381 | if ((c = fgetc(f)) == EOF) break; | |
8523533c | 382 | } |
c007c974 JH |
383 | else if (c == '(') |
384 | { | |
385 | header_open_brackets++; | |
386 | continue; | |
8523533c | 387 | } |
c007c974 JH |
388 | else if ((c == ')') && header_open_brackets) |
389 | { | |
390 | header_open_brackets--; | |
391 | continue; | |
8523533c | 392 | } |
c007c974 JH |
393 | else if ( (c == '=') && !header_open_brackets ) /* enter value mode */ |
394 | header_value_mode = 1; | |
8e669ac1 | 395 | |
c007c974 JH |
396 | /* skip chars while we are in a comment */ |
397 | if (header_open_brackets > 0) | |
398 | continue; | |
399 | /* -------------------------------- */ | |
400 | } | |
8e669ac1 | 401 | |
c007c974 JH |
402 | /* copy the char to the buffer */ |
403 | header[num_copied++] = (uschar)c; | |
8e669ac1 | 404 | |
c007c974 JH |
405 | /* break if header buffer is full */ |
406 | if (num_copied > MIME_MAX_HEADER_SIZE-1) | |
407 | done = 1; | |
408 | } | |
8523533c | 409 | |
c007c974 JH |
410 | if ((num_copied > 0) && (header[num_copied-1] != ';')) |
411 | header[num_copied-1] = ';'; | |
8523533c | 412 | |
c007c974 JH |
413 | /* 0-terminate */ |
414 | header[num_copied] = '\0'; | |
8e669ac1 | 415 | |
c007c974 JH |
416 | /* return 0 for EOF or empty line */ |
417 | if ((c == EOF) || (num_copied == 1)) | |
418 | return 0; | |
419 | else | |
420 | return 1; | |
8523533c TK |
421 | } |
422 | ||
423 | ||
f846c8f5 JH |
424 | static void |
425 | mime_vars_reset(void) | |
426 | { | |
427 | mime_anomaly_level = 0; | |
428 | mime_anomaly_text = NULL; | |
429 | mime_boundary = NULL; | |
430 | mime_charset = NULL; | |
431 | mime_decoded_filename = NULL; | |
432 | mime_filename = NULL; | |
433 | mime_content_description = NULL; | |
434 | mime_content_disposition = NULL; | |
435 | mime_content_id = NULL; | |
436 | mime_content_transfer_encoding = NULL; | |
437 | mime_content_type = NULL; | |
438 | mime_is_multipart = 0; | |
439 | mime_content_size = 0; | |
440 | } | |
441 | ||
442 | ||
443 | /* Grab a parameter value, dealing with quoting. | |
444 | ||
445 | Arguments: | |
446 | str Input string. Updated on return to point to terminating ; or NUL | |
447 | ||
448 | Return: | |
449 | Allocated string with parameter value | |
450 | */ | |
451 | static uschar * | |
452 | mime_param_val(uschar ** sp) | |
453 | { | |
454 | uschar * s = *sp; | |
455 | uschar * val = NULL; | |
456 | int size = 0, ptr = 0; | |
457 | ||
458 | /* debug_printf(" considering paramval '%s'\n", s); */ | |
459 | ||
460 | while (*s && *s != ';') /* ; terminates */ | |
461 | if (*s == '"') | |
462 | { | |
463 | s++; /* skip opening " */ | |
464 | while (*s && *s != '"') /* " protects ; */ | |
465 | val = string_cat(val, &size, &ptr, s++, 1); | |
466 | if (*s) s++; /* skip closing " */ | |
467 | } | |
468 | else | |
469 | val = string_cat(val, &size, &ptr, s++, 1); | |
470 | if (val) val[ptr] = '\0'; | |
471 | *sp = s; | |
472 | return val; | |
473 | } | |
474 | ||
475 | static uschar * | |
476 | mime_next_semicolon(uschar * s) | |
477 | { | |
478 | while (*s && *s != ';') /* ; terminates */ | |
479 | if (*s == '"') | |
480 | { | |
481 | s++; /* skip opening " */ | |
482 | while (*s && *s != '"') /* " protects ; */ | |
483 | s++; | |
484 | if (*s) s++; /* skip closing " */ | |
485 | } | |
486 | else | |
487 | s++; | |
488 | return s; | |
489 | } | |
490 | ||
491 | ||
627d1a1b JH |
492 | static uschar * |
493 | rfc2231_to_2047(const uschar * fname, const uschar * charset, int * len) | |
494 | { | |
495 | int size = 0, ptr = 0; | |
496 | uschar * val = string_cat(NULL, &size, &ptr, US"=?", 2); | |
497 | uschar c; | |
498 | ||
622dbd6a JH |
499 | if (charset) |
500 | val = string_cat(val, &size, &ptr, charset, Ustrlen(charset)); | |
627d1a1b JH |
501 | val = string_cat(val, &size, &ptr, US"?Q?", 3); |
502 | ||
503 | while ((c = *fname)) | |
504 | if (c == '%' && isxdigit(fname[1]) && isxdigit(fname[2])) | |
505 | { | |
506 | val = string_cat(val, &size, &ptr, US"=", 1); | |
507 | val = string_cat(val, &size, &ptr, ++fname, 2); | |
508 | fname += 2; | |
509 | } | |
510 | else | |
511 | val = string_cat(val, &size, &ptr, fname++, 1); | |
512 | ||
513 | val = string_cat(val, &size, &ptr, US"?=", 2); | |
514 | val[*len = ptr] = '\0'; | |
515 | return val; | |
516 | } | |
517 | ||
518 | ||
c007c974 JH |
519 | int |
520 | mime_acl_check(uschar *acl, FILE *f, struct mime_boundary_context *context, | |
f846c8f5 | 521 | uschar **user_msgptr, uschar **log_msgptr) |
c007c974 JH |
522 | { |
523 | int rc = OK; | |
f846c8f5 | 524 | uschar * header = NULL; |
c007c974 JH |
525 | struct mime_boundary_context nested_context; |
526 | ||
527 | /* reserve a line buffer to work in */ | |
f846c8f5 | 528 | header = store_get(MIME_MAX_HEADER_SIZE+1); |
c007c974 JH |
529 | |
530 | /* Not actually used at the moment, but will be vital to fixing | |
531 | * some RFC 2046 nonconformance later... */ | |
532 | nested_context.parent = context; | |
533 | ||
534 | /* loop through parts */ | |
535 | while(1) | |
536 | { | |
537 | /* reset all per-part mime variables */ | |
f846c8f5 JH |
538 | mime_vars_reset(); |
539 | ||
540 | /* If boundary is null, we assume that *f is positioned on the start of | |
541 | headers (for example, at the very beginning of a message. If a boundary is | |
542 | given, we must first advance to it to reach the start of the next header | |
543 | block. */ | |
c007c974 JH |
544 | |
545 | /* NOTE -- there's an error here -- RFC2046 specifically says to | |
546 | * check for outer boundaries. This code doesn't do that, and | |
547 | * I haven't fixed this. | |
548 | * | |
549 | * (I have moved partway towards adding support, however, by adding | |
550 | * a "parent" field to my new boundary-context structure.) | |
551 | */ | |
f846c8f5 | 552 | if (context) for (;;) |
c007c974 | 553 | { |
f846c8f5 | 554 | if (!fgets(CS header, MIME_MAX_HEADER_SIZE, f)) |
c007c974 | 555 | { |
f846c8f5 | 556 | /* Hit EOF or read error. Ugh. */ |
622dbd6a | 557 | DEBUG(D_acl) debug_printf("MIME: Hit EOF ...\n"); |
f846c8f5 JH |
558 | return rc; |
559 | } | |
5c6cf6a0 | 560 | |
f846c8f5 JH |
561 | /* boundary line must start with 2 dashes */ |
562 | if ( Ustrncmp(header, "--", 2) == 0 | |
563 | && Ustrncmp(header+2, context->boundary, Ustrlen(context->boundary)) == 0 | |
564 | ) | |
565 | { /* found boundary */ | |
566 | if (Ustrncmp((header+2+Ustrlen(context->boundary)), "--", 2) == 0) | |
567 | { | |
568 | /* END boundary found */ | |
622dbd6a | 569 | DEBUG(D_acl) debug_printf("MIME: End boundary found %s\n", |
f846c8f5 JH |
570 | context->boundary); |
571 | return rc; | |
c007c974 | 572 | } |
f846c8f5 | 573 | |
622dbd6a | 574 | DEBUG(D_acl) debug_printf("MIME: Next part with boundary %s\n", |
f846c8f5 JH |
575 | context->boundary); |
576 | break; | |
8523533c | 577 | } |
c007c974 | 578 | } |
8e669ac1 | 579 | |
c007c974 | 580 | /* parse headers, set up expansion variables */ |
5c6cf6a0 | 581 | while (mime_get_header(f, header)) |
c007c974 | 582 | { |
f846c8f5 JH |
583 | struct mime_header * mh; |
584 | ||
585 | /* look for interesting headers */ | |
586 | for (mh = mime_header_list; | |
587 | mh < mime_header_list + mime_header_list_size; | |
588 | mh++) if (strncmpic(mh->name, header, mh->namelen) == 0) | |
589 | { | |
f846c8f5 JH |
590 | uschar * p = header + mh->namelen; |
591 | uschar * q; | |
c007c974 | 592 | |
f846c8f5 JH |
593 | /* grab the value (normalize to lower case) |
594 | and copy to its corresponding expansion variable */ | |
595 | ||
596 | for (q = p; *q != ';' && *q; q++) ; | |
597 | *mh->value = string_copynlc(p, q-p); | |
622dbd6a | 598 | DEBUG(D_acl) debug_printf("MIME: found %s header, value is '%s'\n", |
f846c8f5 JH |
599 | mh->name, *mh->value); |
600 | ||
601 | if (*(p = q)) p++; /* jump past the ; */ | |
602 | ||
603 | { | |
604 | uschar * mime_fname = NULL; | |
605 | uschar * mime_fname_rfc2231 = NULL; | |
606 | uschar * mime_filename_charset = NULL; | |
607 | BOOL decoding_failed = FALSE; | |
c007c974 | 608 | |
5c6cf6a0 JH |
609 | /* grab all param=value tags on the remaining line, |
610 | check if they are interesting */ | |
f846c8f5 | 611 | |
5c6cf6a0 | 612 | while (*p) |
c007c974 JH |
613 | { |
614 | mime_parameter * mp; | |
f846c8f5 | 615 | |
622dbd6a | 616 | DEBUG(D_acl) debug_printf("MIME: considering paramlist '%s'\n", p); |
f846c8f5 JH |
617 | |
618 | if ( !mime_filename | |
fc362fc5 JH |
619 | && strncmpic(CUS"content-disposition:", header, 20) == 0 |
620 | && strncmpic(CUS"filename*", p, 9) == 0 | |
f846c8f5 JH |
621 | ) |
622 | { /* RFC 2231 filename */ | |
623 | uschar * q; | |
624 | ||
625 | /* find value of the filename */ | |
626 | p += 9; | |
627 | while(*p != '=' && *p) p++; | |
628 | if (*p) p++; /* p is filename or NUL */ | |
629 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
630 | ||
631 | if (q && *q) | |
c007c974 | 632 | { |
f846c8f5 JH |
633 | uschar * temp_string, * err_msg; |
634 | int slen; | |
4fd5d2bf | 635 | |
f846c8f5 JH |
636 | /* build up an un-decoded filename over successive |
637 | filename*= parameters (for use when 2047 decode fails) */ | |
638 | ||
639 | mime_fname_rfc2231 = string_sprintf("%#s%s", | |
640 | mime_fname_rfc2231, q); | |
641 | ||
642 | if (!decoding_failed) | |
643 | { | |
644 | int size; | |
645 | if (!mime_filename_charset) | |
4fd5d2bf | 646 | { |
f846c8f5 JH |
647 | uschar * s = q; |
648 | ||
649 | /* look for a ' in the "filename" */ | |
622dbd6a | 650 | while(*s != '\'' && *s) s++; /* s is 1st ' or NUL */ |
f846c8f5 JH |
651 | |
652 | if ((size = s-q) > 0) | |
f846c8f5 | 653 | mime_filename_charset = string_copyn(q, size); |
f846c8f5 | 654 | |
622dbd6a JH |
655 | if (*(p = s)) p++; |
656 | while(*p == '\'') p++; /* p is after 2nd ' */ | |
4fd5d2bf JH |
657 | } |
658 | else | |
f846c8f5 | 659 | p = q; |
5c6cf6a0 | 660 | |
622dbd6a JH |
661 | DEBUG(D_acl) debug_printf("MIME: charset %s fname '%s'\n", |
662 | mime_filename_charset ? mime_filename_charset : US"<NULL>", p); | |
663 | ||
627d1a1b | 664 | temp_string = rfc2231_to_2047(p, mime_filename_charset, &slen); |
622dbd6a JH |
665 | DEBUG(D_acl) debug_printf("MIME: 2047-name %s\n", temp_string); |
666 | ||
667 | temp_string = rfc2047_decode(temp_string, FALSE, NULL, ' ', | |
f846c8f5 | 668 | NULL, &err_msg); |
622dbd6a JH |
669 | DEBUG(D_acl) debug_printf("MIME: plain-name %s\n", temp_string); |
670 | ||
f846c8f5 JH |
671 | size = Ustrlen(temp_string); |
672 | ||
673 | if (size == slen) | |
674 | decoding_failed = TRUE; | |
675 | else | |
676 | /* build up a decoded filename over successive | |
677 | filename*= parameters */ | |
678 | ||
679 | mime_filename = mime_fname = mime_fname | |
680 | ? string_sprintf("%s%s", mime_fname, temp_string) | |
681 | : temp_string; | |
93cad488 | 682 | } |
f846c8f5 | 683 | } |
5c6cf6a0 | 684 | } |
f846c8f5 | 685 | |
e7c25d5b | 686 | else |
f846c8f5 JH |
687 | /* look for interesting parameters */ |
688 | for (mp = mime_parameter_list; | |
689 | mp < mime_parameter_list + nelem(mime_parameter_list); | |
690 | mp++ | |
691 | ) if (strncmpic(mp->name, p, mp->namelen) == 0) | |
692 | { | |
693 | uschar * q; | |
694 | uschar * dummy_errstr; | |
695 | ||
696 | /* grab the value and copy to its expansion variable */ | |
697 | p += mp->namelen; | |
698 | q = mime_param_val(&p); /* p now trailing ; or NUL */ | |
699 | ||
700 | *mp->value = q && *q | |
701 | ? rfc2047_decode(q, check_rfc2047_length, NULL, 32, NULL, | |
702 | &dummy_errstr) | |
703 | : NULL; | |
704 | DEBUG(D_acl) debug_printf( | |
622dbd6a | 705 | "MIME: found %s parameter in %s header, value '%s'\n", |
f846c8f5 JH |
706 | mp->name, mh->name, *mp->value); |
707 | ||
708 | break; /* done matching param names */ | |
709 | } | |
710 | ||
711 | ||
712 | /* There is something, but not one of our interesting parameters. | |
713 | Advance past the next semicolon */ | |
714 | p = mime_next_semicolon(p); | |
715 | if (*p) p++; | |
716 | } /* param scan on line */ | |
717 | ||
fc362fc5 | 718 | if (strncmpic(CUS"content-disposition:", header, 20) == 0) |
f846c8f5 JH |
719 | { |
720 | if (decoding_failed) mime_filename = mime_fname_rfc2231; | |
721 | ||
722 | DEBUG(D_acl) debug_printf( | |
622dbd6a | 723 | "MIME: found %s parameter in %s header, value is '%s'\n", |
f846c8f5 JH |
724 | "filename", mh->name, mime_filename); |
725 | } | |
c007c974 JH |
726 | } |
727 | } | |
f846c8f5 | 728 | } |
8e669ac1 | 729 | |
c007c974 | 730 | /* set additional flag variables (easier access) */ |
f846c8f5 JH |
731 | if ( mime_content_type |
732 | && Ustrncmp(mime_content_type,"multipart",9) == 0 | |
733 | ) | |
c007c974 | 734 | mime_is_multipart = 1; |
8e669ac1 | 735 | |
c007c974 JH |
736 | /* Make a copy of the boundary pointer. |
737 | Required since mime_boundary is global | |
738 | and can be overwritten further down in recursion */ | |
739 | nested_context.boundary = mime_boundary; | |
8e669ac1 | 740 | |
c007c974 JH |
741 | /* raise global counter */ |
742 | mime_part_count++; | |
8523533c | 743 | |
c007c974 JH |
744 | /* copy current file handle to global variable */ |
745 | mime_stream = f; | |
746 | mime_current_boundary = context ? context->boundary : 0; | |
8e669ac1 | 747 | |
c007c974 JH |
748 | /* Note the context */ |
749 | mime_is_coverletter = !(context && context->context == MBC_ATTACHMENT); | |
8e669ac1 | 750 | |
c007c974 JH |
751 | /* call ACL handling function */ |
752 | rc = acl_check(ACL_WHERE_MIME, NULL, acl, user_msgptr, log_msgptr); | |
8e669ac1 | 753 | |
c007c974 JH |
754 | mime_stream = NULL; |
755 | mime_current_boundary = NULL; | |
756 | ||
757 | if (rc != OK) break; | |
8e669ac1 | 758 | |
c007c974 JH |
759 | /* If we have a multipart entity and a boundary, go recursive */ |
760 | if ( (mime_content_type != NULL) && | |
761 | (nested_context.boundary != NULL) && | |
762 | (Ustrncmp(mime_content_type,"multipart",9) == 0) ) | |
763 | { | |
622dbd6a JH |
764 | DEBUG(D_acl) |
765 | debug_printf("MIME: Entering multipart recursion, boundary '%s'\n", | |
766 | nested_context.boundary); | |
c007c974 JH |
767 | |
768 | nested_context.context = | |
769 | context && context->context == MBC_ATTACHMENT | |
770 | ? MBC_ATTACHMENT | |
771 | : Ustrcmp(mime_content_type,"multipart/alternative") == 0 | |
772 | || Ustrcmp(mime_content_type,"multipart/related") == 0 | |
773 | ? MBC_COVERLETTER_ALL | |
774 | : MBC_COVERLETTER_ONESHOT; | |
775 | ||
776 | rc = mime_acl_check(acl, f, &nested_context, user_msgptr, log_msgptr); | |
777 | if (rc != OK) break; | |
8523533c | 778 | } |
c007c974 JH |
779 | else if ( (mime_content_type != NULL) && |
780 | (Ustrncmp(mime_content_type,"message/rfc822",14) == 0) ) | |
781 | { | |
55414b25 | 782 | const uschar *rfc822name = NULL; |
c007c974 JH |
783 | uschar filename[2048]; |
784 | int file_nr = 0; | |
785 | int result = 0; | |
8e669ac1 | 786 | |
c007c974 JH |
787 | /* must find first free sequential filename */ |
788 | do | |
789 | { | |
790 | struct stat mystat; | |
791 | (void)string_format(filename, 2048, | |
792 | "%s/scan/%s/__rfc822_%05u", spool_directory, message_id, file_nr++); | |
793 | /* security break */ | |
794 | if (file_nr >= 128) | |
795 | goto NO_RFC822; | |
796 | result = stat(CS filename,&mystat); | |
797 | } while (result != -1); | |
798 | ||
799 | rfc822name = filename; | |
800 | ||
801 | /* decode RFC822 attachment */ | |
802 | mime_decoded_filename = NULL; | |
803 | mime_stream = f; | |
804 | mime_current_boundary = context ? context->boundary : NULL; | |
805 | mime_decode(&rfc822name); | |
806 | mime_stream = NULL; | |
807 | mime_current_boundary = NULL; | |
808 | if (!mime_decoded_filename) /* decoding failed */ | |
809 | { | |
810 | log_write(0, LOG_MAIN, | |
811 | "mime_regex acl condition warning - could not decode RFC822 MIME part to file."); | |
f846c8f5 JH |
812 | rc = DEFER; |
813 | goto out; | |
c007c974 JH |
814 | } |
815 | mime_decoded_filename = NULL; | |
816 | } | |
8523533c | 817 | |
c007c974 JH |
818 | NO_RFC822: |
819 | /* If the boundary of this instance is NULL, we are finished here */ | |
f846c8f5 | 820 | if (!context) break; |
8e669ac1 | 821 | |
c007c974 JH |
822 | if (context->context == MBC_COVERLETTER_ONESHOT) |
823 | context->context = MBC_ATTACHMENT; | |
824 | } | |
8523533c | 825 | |
f846c8f5 JH |
826 | out: |
827 | mime_vars_reset(); | |
c007c974 | 828 | return rc; |
8523533c TK |
829 | } |
830 | ||
c007c974 JH |
831 | #endif /*WITH_CONTENT_SCAN*/ |
832 | ||
833 | /* vi: sw ai sw=2 | |
834 | */ |