Documentation/Tests for CVE-2014-2972 fix
[exim.git] / src / src / mime.c
CommitLineData
8523533c
TK
1/*************************************************
2* Exim - an Internet mail transport agent *
3*************************************************/
4
5/* Copyright (c) Tom Kistner <tom@duncanthrax.net> 2004 */
6/* License: GPL */
7
8#include "exim.h"
9#ifdef WITH_CONTENT_SCAN
10#include "mime.h"
11#include <sys/stat.h>
12
13FILE *mime_stream = NULL;
14uschar *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
1ba28e2b 24void mime_set_anomaly(int level, const char *text) {
8523533c 25 mime_anomaly_level = level;
1ba28e2b 26 mime_anomaly_text = CUS text;
f7b63901 27}
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28
29
30/*************************************************
31* decode quoted-printable chars *
32*************************************************/
33
34/* gets called when we hit a =
35 returns: new pointer position
36 result code in c:
37 -2 - decode error
38 -1 - soft line break, no char
39 0-255 - char to write
40*/
41
d203e649 42uschar *mime_decode_qp_char(uschar *qp_p, int *c) {
8523533c 43 uschar *initial_pos = qp_p;
8e669ac1 44
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TK
45 /* advance one char */
46 qp_p++;
8e669ac1 47
d203e649
PH
48 /* Check for two hex digits and decode them */
49 if (isxdigit(*qp_p) && isxdigit(qp_p[1])) {
50 /* Do hex conversion */
51 if (isdigit(*qp_p)) {*c = *qp_p - '0';}
52 else {*c = toupper(*qp_p) - 'A' + 10;};
53 *c <<= 4;
54 if (isdigit(qp_p[1])) {*c |= qp_p[1] - '0';}
55 else {*c |= toupper(qp_p[1]) - 'A' + 10;};
56 return qp_p + 2;
57 };
58
59 /* tab or whitespace may follow just ignore it if it precedes \n */
60 while (*qp_p == '\t' || *qp_p == ' ' || *qp_p == '\r')
8523533c 61 qp_p++;
d203e649
PH
62
63 if (*qp_p == '\n') {
64 /* hit soft line break */
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TK
65 *c = -1;
66 return qp_p;
8523533c 67 };
8e669ac1 68
d203e649
PH
69 /* illegal char here */
70 *c = -2;
71 return initial_pos;
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72}
73
74
baee9eee 75/* just dump MIME part without any decoding */
eb02738d
PP
76static ssize_t
77mime_decode_asis(FILE* in, FILE* out, uschar* boundary)
baee9eee 78{
eb02738d 79 ssize_t len, size = 0;
baee9eee 80 uschar buffer[MIME_MAX_LINE_LENGTH];
d203e649 81
baee9eee
NM
82 while(fgets(CS buffer, MIME_MAX_LINE_LENGTH, mime_stream) != NULL) {
83 if (boundary != NULL
84 && Ustrncmp(buffer, "--", 2) == 0
85 && Ustrncmp((buffer+2), boundary, Ustrlen(boundary)) == 0
86 )
87 break;
88
89 len = Ustrlen(buffer);
90 if (fwrite(buffer, 1, (size_t)len, out) < len)
91 return -1;
92 size += len;
93 } /* while */
94 return size;
95}
84330b7b 96
8523533c 97
baee9eee 98/* decode base64 MIME part */
eb02738d
PP
99static ssize_t
100mime_decode_base64(FILE* in, FILE* out, uschar* boundary)
baee9eee
NM
101{
102 uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH];
103 uschar *ipos, *opos;
eb02738d 104 ssize_t len, size = 0;
baee9eee
NM
105 int bytestate = 0;
106
107 opos = obuf;
108
7156b1ef 109 while (Ufgets(ibuf, MIME_MAX_LINE_LENGTH, in) != NULL)
baee9eee
NM
110 {
111 if (boundary != NULL
112 && Ustrncmp(ibuf, "--", 2) == 0
113 && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0
114 )
115 break;
116
117 for (ipos = ibuf ; *ipos != '\r' && *ipos != '\n' && *ipos != 0; ++ipos) {
118 /* skip padding */
119 if (*ipos == '=') {
120 ++bytestate;
121 continue;
122 }
123 /* skip bad characters */
124 if (mime_b64[*ipos] == 128) {
8523533c 125 mime_set_anomaly(MIME_ANOMALY_BROKEN_BASE64);
baee9eee 126 continue;
8523533c 127 }
baee9eee
NM
128 /* simple state-machine */
129 switch((bytestate++) & 3) {
130 case 0:
131 *opos = mime_b64[*ipos] << 2;
132 break;
133 case 1:
134 *opos |= mime_b64[*ipos] >> 4;
135 ++opos;
136 *opos = mime_b64[*ipos] << 4;
137 break;
138 case 2:
139 *opos |= mime_b64[*ipos] >> 2;
140 ++opos;
141 *opos = mime_b64[*ipos] << 6;
142 break;
143 case 3:
144 *opos |= mime_b64[*ipos];
145 ++opos;
146 break;
147 } /* switch */
148 } /* for */
149 /* something to write? */
150 len = opos - obuf;
151 if (len > 0) {
152 if (fwrite(obuf, 1, len, out) != len)
153 return -1; /* error */
154 size += len;
155 /* copy incomplete last byte to start of obuf, where we continue */
7156b1ef 156 if ((bytestate & 3) != 0)
baee9eee
NM
157 *obuf = *opos;
158 opos = obuf;
159 }
160 } /* while */
161
162 /* write out last byte if it was incomplete */
163 if (bytestate & 3) {
164 if (fwrite(obuf, 1, 1, out) != 1)
165 return -1;
166 ++size;
167 }
8e669ac1 168
baee9eee
NM
169 return size;
170}
8e669ac1 171
8e669ac1 172
baee9eee 173/* decode quoted-printable MIME part */
eb02738d
PP
174static ssize_t
175mime_decode_qp(FILE* in, FILE* out, uschar* boundary)
baee9eee
NM
176{
177 uschar ibuf[MIME_MAX_LINE_LENGTH], obuf[MIME_MAX_LINE_LENGTH];
178 uschar *ipos, *opos;
eb02738d 179 ssize_t len, size = 0;
baee9eee
NM
180
181 while (fgets(CS ibuf, MIME_MAX_LINE_LENGTH, in) != NULL)
182 {
183 if (boundary != NULL
184 && Ustrncmp(ibuf, "--", 2) == 0
185 && Ustrncmp((ibuf+2), boundary, Ustrlen(boundary)) == 0
186 )
187 break; /* todo: check for missing boundary */
8523533c 188
baee9eee
NM
189 ipos = ibuf;
190 opos = obuf;
191
192 while (*ipos != 0) {
193 if (*ipos == '=') {
8523533c 194 int decode_qp_result;
8e669ac1 195
baee9eee 196 ipos = mime_decode_qp_char(ipos, &decode_qp_result);
8e669ac1 197
8523533c 198 if (decode_qp_result == -2) {
baee9eee 199 /* Error from decoder. ipos is unchanged. */
8523533c 200 mime_set_anomaly(MIME_ANOMALY_BROKEN_QP);
baee9eee
NM
201 *opos = '=';
202 ++opos;
203 ++ipos;
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TK
204 }
205 else if (decode_qp_result == -1) {
206 break;
207 }
208 else if (decode_qp_result >= 0) {
baee9eee
NM
209 *opos = decode_qp_result;
210 ++opos;
211 }
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212 }
213 else {
baee9eee
NM
214 *opos = *ipos;
215 ++opos;
216 ++ipos;
217 }
218 }
219 /* something to write? */
220 len = opos - obuf;
221 if (len > 0) {
222 if (fwrite(obuf, 1, len, out) != len)
223 return -1; /* error */
224 size += len;
225 }
8523533c 226 }
baee9eee 227 return size;
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228}
229
230
231FILE *mime_get_decode_file(uschar *pname, uschar *fname) {
f7b63901 232 FILE *f = NULL;
8523533c 233 uschar *filename;
8e669ac1 234
8523533c 235 filename = (uschar *)malloc(2048);
8e669ac1 236
8523533c 237 if ((pname != NULL) && (fname != NULL)) {
b07e6aa3 238 (void)string_format(filename, 2048, "%s/%s", pname, fname);
2632889e 239 f = modefopen(filename,"wb+",SPOOL_MODE);
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240 }
241 else if (pname == NULL) {
2632889e 242 f = modefopen(fname,"wb+",SPOOL_MODE);
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243 }
244 else if (fname == NULL) {
245 int file_nr = 0;
246 int result = 0;
247
248 /* must find first free sequential filename */
249 do {
250 struct stat mystat;
b07e6aa3 251 (void)string_format(filename,2048,"%s/%s-%05u", pname, message_id, file_nr);
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252 file_nr++;
253 /* security break */
254 if (file_nr >= 1024)
255 break;
256 result = stat(CS filename,&mystat);
257 }
258 while(result != -1);
2632889e 259 f = modefopen(filename,"wb+",SPOOL_MODE);
8523533c 260 };
8e669ac1 261
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262 /* set expansion variable */
263 mime_decoded_filename = filename;
8e669ac1 264
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265 return f;
266}
267
268
269int mime_decode(uschar **listptr) {
270 int sep = 0;
271 uschar *list = *listptr;
272 uschar *option;
273 uschar option_buffer[1024];
274 uschar decode_path[1024];
275 FILE *decode_file = NULL;
8523533c 276 long f_pos = 0;
eb02738d
PP
277 ssize_t size_counter = 0;
278 ssize_t (*decode_function)(FILE*, FILE*, uschar*);
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TK
279
280 if (mime_stream == NULL)
281 return FAIL;
8e669ac1 282
8523533c 283 f_pos = ftell(mime_stream);
8e669ac1 284
8523533c 285 /* build default decode path (will exist since MBOX must be spooled up) */
b07e6aa3 286 (void)string_format(decode_path,1024,"%s/scan/%s",spool_directory,message_id);
8e669ac1 287
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288 /* try to find 1st option */
289 if ((option = string_nextinlist(&list, &sep,
290 option_buffer,
291 sizeof(option_buffer))) != NULL) {
8e669ac1 292
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TK
293 /* parse 1st option */
294 if ( (Ustrcmp(option,"false") == 0) || (Ustrcmp(option,"0") == 0) ) {
295 /* explicitly no decoding */
296 return FAIL;
297 };
8e669ac1 298
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TK
299 if (Ustrcmp(option,"default") == 0) {
300 /* explicit default path + file names */
301 goto DEFAULT_PATH;
302 };
8e669ac1 303
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TK
304 if (option[0] == '/') {
305 struct stat statbuf;
306
307 memset(&statbuf,0,sizeof(statbuf));
8e669ac1 308
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309 /* assume either path or path+file name */
310 if ( (stat(CS option, &statbuf) == 0) && S_ISDIR(statbuf.st_mode) )
311 /* is directory, use it as decode_path */
312 decode_file = mime_get_decode_file(option, NULL);
313 else
314 /* does not exist or is a file, use as full file name */
315 decode_file = mime_get_decode_file(NULL, option);
316 }
317 else
318 /* assume file name only, use default path */
319 decode_file = mime_get_decode_file(decode_path, option);
320 }
321 else
322 /* no option? patch default path */
323 DEFAULT_PATH: decode_file = mime_get_decode_file(decode_path, NULL);
8e669ac1 324
8523533c
TK
325 if (decode_file == NULL)
326 return DEFER;
8e669ac1 327
baee9eee
NM
328 /* decode according to mime type */
329 if (mime_content_transfer_encoding == NULL)
330 /* no encoding, dump as-is */
331 decode_function = mime_decode_asis;
332 else if (Ustrcmp(mime_content_transfer_encoding, "base64") == 0)
333 decode_function = mime_decode_base64;
334 else if (Ustrcmp(mime_content_transfer_encoding, "quoted-printable") == 0)
335 decode_function = mime_decode_qp;
336 else
337 /* unknown encoding type, just dump as-is */
338 decode_function = mime_decode_asis;
8e669ac1 339
baee9eee 340 size_counter = decode_function(mime_stream, decode_file, mime_current_boundary);
8e669ac1 341
8523533c 342 clearerr(mime_stream);
baee9eee 343 fseek(mime_stream, f_pos, SEEK_SET);
8e669ac1 344
61da1593 345 if (fclose(decode_file) != 0 || size_counter < 0)
baee9eee
NM
346 return DEFER;
347
348 /* round up to the next KiB */
349 mime_content_size = (size_counter + 1023) / 1024;
8e669ac1 350
8523533c
TK
351 return OK;
352}
353
354int mime_get_header(FILE *f, uschar *header) {
355 int c = EOF;
356 int done = 0;
357 int header_value_mode = 0;
358 int header_open_brackets = 0;
359 int num_copied = 0;
8e669ac1 360
8523533c 361 while(!done) {
8e669ac1 362
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TK
363 c = fgetc(f);
364 if (c == EOF) break;
8e669ac1 365
8523533c
TK
366 /* always skip CRs */
367 if (c == '\r') continue;
8e669ac1 368
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TK
369 if (c == '\n') {
370 if (num_copied > 0) {
371 /* look if next char is '\t' or ' ' */
372 c = fgetc(f);
373 if (c == EOF) break;
374 if ( (c == '\t') || (c == ' ') ) continue;
f1e894f3 375 (void)ungetc(c,f);
8523533c
TK
376 };
377 /* end of the header, terminate with ';' */
378 c = ';';
379 done = 1;
380 };
8e669ac1 381
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TK
382 /* skip control characters */
383 if (c < 32) continue;
384
385 if (header_value_mode) {
386 /* --------- value mode ----------- */
387 /* skip leading whitespace */
388 if ( ((c == '\t') || (c == ' ')) && (header_value_mode == 1) )
389 continue;
8e669ac1 390
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TK
391 /* we have hit a non-whitespace char, start copying value data */
392 header_value_mode = 2;
8e669ac1 393
1bd0d12b
JH
394 if (c == '"') /* flip "quoted" mode */
395 header_value_mode = header_value_mode==2 ? 3 : 2;
8e669ac1 396
1bd0d12b
JH
397 /* leave value mode on unquoted ';' */
398 if (header_value_mode == 2 && c == ';') {
8523533c
TK
399 header_value_mode = 0;
400 };
401 /* -------------------------------- */
402 }
403 else {
404 /* -------- non-value mode -------- */
405 /* skip whitespace + tabs */
406 if ( (c == ' ') || (c == '\t') )
407 continue;
408 if (c == '\\') {
409 /* quote next char. can be used
410 to escape brackets. */
411 c = fgetc(f);
412 if (c == EOF) break;
413 }
414 else if (c == '(') {
415 header_open_brackets++;
416 continue;
417 }
418 else if ((c == ')') && header_open_brackets) {
419 header_open_brackets--;
420 continue;
421 }
422 else if ( (c == '=') && !header_open_brackets ) {
423 /* enter value mode */
424 header_value_mode = 1;
425 };
8e669ac1 426
8523533c
TK
427 /* skip chars while we are in a comment */
428 if (header_open_brackets > 0)
429 continue;
430 /* -------------------------------- */
431 };
8e669ac1 432
8523533c
TK
433 /* copy the char to the buffer */
434 header[num_copied] = (uschar)c;
435 /* raise counter */
436 num_copied++;
8e669ac1 437
8523533c
TK
438 /* break if header buffer is full */
439 if (num_copied > MIME_MAX_HEADER_SIZE-1) {
440 done = 1;
441 };
442 };
443
9f093f3a 444 if ((num_copied > 0) && (header[num_copied-1] != ';')) {
8523533c
TK
445 header[num_copied-1] = ';';
446 };
447
448 /* 0-terminate */
449 header[num_copied] = '\0';
8e669ac1 450
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TK
451 /* return 0 for EOF or empty line */
452 if ((c == EOF) || (num_copied == 1))
453 return 0;
454 else
455 return 1;
456}
457
458
54cdb463
PH
459int mime_acl_check(uschar *acl, FILE *f, struct mime_boundary_context *context,
460 uschar **user_msgptr, uschar **log_msgptr) {
8523533c
TK
461 int rc = OK;
462 uschar *header = NULL;
463 struct mime_boundary_context nested_context;
464
465 /* reserve a line buffer to work in */
466 header = (uschar *)malloc(MIME_MAX_HEADER_SIZE+1);
467 if (header == NULL) {
468 log_write(0, LOG_PANIC,
54cdb463 469 "MIME ACL: can't allocate %d bytes of memory.", MIME_MAX_HEADER_SIZE+1);
8523533c
TK
470 return DEFER;
471 };
472
473 /* Not actually used at the moment, but will be vital to fixing
474 * some RFC 2046 nonconformance later... */
475 nested_context.parent = context;
476
477 /* loop through parts */
478 while(1) {
8e669ac1 479
8523533c 480 /* reset all per-part mime variables */
f7b63901 481 mime_anomaly_level = 0;
8523533c
TK
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;
8e669ac1 494
8523533c
TK
495 /*
496 If boundary is null, we assume that *f is positioned on the start of headers (for example,
497 at the very beginning of a message.
498 If a boundary is given, we must first advance to it to reach the start of the next header
499 block.
500 */
8e669ac1 501
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TK
502 /* NOTE -- there's an error here -- RFC2046 specifically says to
503 * check for outer boundaries. This code doesn't do that, and
504 * I haven't fixed this.
505 *
8e669ac1 506 * (I have moved partway towards adding support, however, by adding
8523533c
TK
507 * a "parent" field to my new boundary-context structure.)
508 */
509 if (context != NULL) {
510 while(fgets(CS header, MIME_MAX_HEADER_SIZE, f) != NULL) {
511 /* boundary line must start with 2 dashes */
512 if (Ustrncmp(header,"--",2) == 0) {
513 if (Ustrncmp((header+2),context->boundary,Ustrlen(context->boundary)) == 0) {
514 /* found boundary */
515 if (Ustrncmp((header+2+Ustrlen(context->boundary)),"--",2) == 0) {
516 /* END boundary found */
517 debug_printf("End boundary found %s\n", context->boundary);
518 return rc;
519 }
520 else {
521 debug_printf("Next part with boundary %s\n", context->boundary);
522 };
523 /* can't use break here */
524 goto DECODE_HEADERS;
525 }
526 };
527 }
528 /* Hit EOF or read error. Ugh. */
529 debug_printf("Hit EOF ...\n");
530 return rc;
531 };
8e669ac1 532
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TK
533 DECODE_HEADERS:
534 /* parse headers, set up expansion variables */
535 while(mime_get_header(f,header)) {
536 int i;
537 /* loop through header list */
538 for (i = 0; i < mime_header_list_size; i++) {
539 uschar *header_value = NULL;
540 int header_value_len = 0;
8e669ac1 541
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TK
542 /* found an interesting header? */
543 if (strncmpic(mime_header_list[i].name,header,mime_header_list[i].namelen) == 0) {
544 uschar *p = header + mime_header_list[i].namelen;
545 /* yes, grab the value (normalize to lower case)
546 and copy to its corresponding expansion variable */
547 while(*p != ';') {
548 *p = tolower(*p);
549 p++;
550 };
551 header_value_len = (p - (header + mime_header_list[i].namelen));
552 header_value = (uschar *)malloc(header_value_len+1);
553 memset(header_value,0,header_value_len+1);
554 p = header + mime_header_list[i].namelen;
555 Ustrncpy(header_value, p, header_value_len);
556 debug_printf("Found %s MIME header, value is '%s'\n", mime_header_list[i].name, header_value);
557 *((uschar **)(mime_header_list[i].value)) = header_value;
8e669ac1 558
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TK
559 /* make p point to the next character after the closing ';' */
560 p += (header_value_len+1);
8e669ac1 561
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TK
562 /* grab all param=value tags on the remaining line, check if they are interesting */
563 NEXT_PARAM_SEARCH: while (*p != 0) {
564 int j;
565 for (j = 0; j < mime_parameter_list_size; j++) {
566 uschar *param_value = NULL;
567 int param_value_len = 0;
8e669ac1 568
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TK
569 /* found an interesting parameter? */
570 if (strncmpic(mime_parameter_list[j].name,p,mime_parameter_list[j].namelen) == 0) {
571 uschar *q = p + mime_parameter_list[j].namelen;
572 /* yes, grab the value and copy to its corresponding expansion variable */
1bd0d12b
JH
573 while (*q && *q != ';')
574 {
575 if (*q == '"') do q++; while (*q != '"');
576 q++;
577 }
578
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TK
579 param_value_len = (q - (p + mime_parameter_list[j].namelen));
580 param_value = (uschar *)malloc(param_value_len+1);
581 memset(param_value,0,param_value_len+1);
582 q = p + mime_parameter_list[j].namelen;
583 Ustrncpy(param_value, q, param_value_len);
a0d6ba8a 584 param_value = rfc2047_decode(param_value, check_rfc2047_length, NULL, 32, &param_value_len, &q);
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TK
585 debug_printf("Found %s MIME parameter in %s header, value is '%s'\n", mime_parameter_list[j].name, mime_header_list[i].name, param_value);
586 *((uschar **)(mime_parameter_list[j].value)) = param_value;
587 p += (mime_parameter_list[j].namelen + param_value_len + 1);
588 goto NEXT_PARAM_SEARCH;
589 };
590 }
591 /* There is something, but not one of our interesting parameters.
592 Advance to the next semicolon */
593 while(*p != ';') p++;
594 p++;
595 };
596 };
597 };
598 };
8e669ac1 599
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TK
600 /* set additional flag variables (easier access) */
601 if ( (mime_content_type != NULL) &&
602 (Ustrncmp(mime_content_type,"multipart",9) == 0) )
603 mime_is_multipart = 1;
8e669ac1 604
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TK
605 /* Make a copy of the boundary pointer.
606 Required since mime_boundary is global
607 and can be overwritten further down in recursion */
608 nested_context.boundary = mime_boundary;
8e669ac1 609
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TK
610 /* raise global counter */
611 mime_part_count++;
8e669ac1 612
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TK
613 /* copy current file handle to global variable */
614 mime_stream = f;
615 mime_current_boundary = context ? context->boundary : 0;
616
617 /* Note the context */
618 mime_is_coverletter = !(context && context->context == MBC_ATTACHMENT);
8e669ac1 619
8523533c 620 /* call ACL handling function */
54cdb463 621 rc = acl_check(ACL_WHERE_MIME, NULL, acl, user_msgptr, log_msgptr);
8e669ac1 622
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TK
623 mime_stream = NULL;
624 mime_current_boundary = NULL;
8e669ac1 625
8523533c 626 if (rc != OK) break;
8e669ac1 627
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628 /* If we have a multipart entity and a boundary, go recursive */
629 if ( (mime_content_type != NULL) &&
630 (nested_context.boundary != NULL) &&
631 (Ustrncmp(mime_content_type,"multipart",9) == 0) ) {
632 debug_printf("Entering multipart recursion, boundary '%s'\n", nested_context.boundary);
633
634 if (context && context->context == MBC_ATTACHMENT)
635 nested_context.context = MBC_ATTACHMENT;
636 else if (!Ustrcmp(mime_content_type,"multipart/alternative")
637 || !Ustrcmp(mime_content_type,"multipart/related"))
638 nested_context.context = MBC_COVERLETTER_ALL;
639 else
640 nested_context.context = MBC_COVERLETTER_ONESHOT;
641
54cdb463 642 rc = mime_acl_check(acl, f, &nested_context, user_msgptr, log_msgptr);
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643 if (rc != OK) break;
644 }
645 else if ( (mime_content_type != NULL) &&
646 (Ustrncmp(mime_content_type,"message/rfc822",14) == 0) ) {
647 uschar *rfc822name = NULL;
648 uschar filename[2048];
649 int file_nr = 0;
650 int result = 0;
8e669ac1 651
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652 /* must find first free sequential filename */
653 do {
654 struct stat mystat;
b07e6aa3 655 (void)string_format(filename,2048,"%s/scan/%s/__rfc822_%05u", spool_directory, message_id, file_nr);
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656 file_nr++;
657 /* security break */
658 if (file_nr >= 128)
659 goto NO_RFC822;
660 result = stat(CS filename,&mystat);
661 }
662 while(result != -1);
8e669ac1 663
8523533c 664 rfc822name = filename;
8e669ac1 665
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666 /* decode RFC822 attachment */
667 mime_decoded_filename = NULL;
668 mime_stream = f;
669 mime_current_boundary = context ? context->boundary : NULL;
670 mime_decode(&rfc822name);
671 mime_stream = NULL;
672 mime_current_boundary = NULL;
673 if (mime_decoded_filename == NULL) {
674 /* decoding failed */
675 log_write(0, LOG_MAIN,
676 "mime_regex acl condition warning - could not decode RFC822 MIME part to file.");
677 return DEFER;
678 };
679 mime_decoded_filename = NULL;
680 };
8e669ac1 681
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682 NO_RFC822:
683 /* If the boundary of this instance is NULL, we are finished here */
684 if (context == NULL) break;
685
686 if (context->context == MBC_COVERLETTER_ONESHOT)
687 context->context = MBC_ATTACHMENT;
8e669ac1 688
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689 };
690
691 return rc;
692}
693
694#endif