Commit | Line | Data |
---|---|---|
059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
f9ba5e22 | 5 | /* Copyright (c) University of Cambridge 1995 - 2018 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* This module contains code for extracting addresses from a forwarding list | |
9 | (from an alias or forward file) or by running the filter interpreter. It may do | |
10 | this in a sub-process if a uid/gid are supplied. */ | |
11 | ||
12 | ||
13 | #include "exim.h" | |
14 | ||
15 | enum { FILE_EXIST, FILE_NOT_EXIST, FILE_EXIST_UNCLEAR }; | |
16 | ||
17 | #define REPLY_EXISTS 0x01 | |
18 | #define REPLY_EXPAND 0x02 | |
19 | #define REPLY_RETURN 0x04 | |
20 | ||
21 | ||
22 | /************************************************* | |
23 | * Check string for filter program * | |
24 | *************************************************/ | |
25 | ||
26 | /* This function checks whether a string is actually a filter program. The rule | |
27 | is that it must start with "# Exim filter ..." (any capitalization, spaces | |
28 | optional). It is envisaged that in future, other kinds of filter may be | |
29 | implemented. That's why it is implemented the way it is. The function is global | |
30 | because it is also called from filter.c when checking filters. | |
31 | ||
32 | Argument: the string | |
33 | ||
34 | Returns: FILTER_EXIM if it starts with "# Exim filter" | |
35 | FILTER_SIEVE if it starts with "# Sieve filter" | |
36 | FILTER_FORWARD otherwise | |
37 | */ | |
38 | ||
39 | /* This is an auxiliary function for matching a tag. */ | |
40 | ||
41 | static BOOL | |
42 | match_tag(const uschar *s, const uschar *tag) | |
43 | { | |
44 | for (; *tag != 0; s++, tag++) | |
059ec3d9 PH |
45 | if (*tag == ' ') |
46 | { | |
47 | while (*s == ' ' || *s == '\t') s++; | |
48 | s--; | |
49 | } | |
d7978c0f JH |
50 | else |
51 | if (tolower(*s) != tolower(*tag)) break; | |
52 | ||
059ec3d9 PH |
53 | return (*tag == 0); |
54 | } | |
55 | ||
56 | /* This is the real function. It should be easy to add checking different | |
57 | tags for other types of filter. */ | |
58 | ||
59 | int | |
60 | rda_is_filter(const uschar *s) | |
61 | { | |
62 | while (isspace(*s)) s++; /* Skips initial blank lines */ | |
63 | if (match_tag(s, CUS"# exim filter")) return FILTER_EXIM; | |
64 | else if (match_tag(s, CUS"# sieve filter")) return FILTER_SIEVE; | |
65 | else return FILTER_FORWARD; | |
66 | } | |
67 | ||
68 | ||
69 | ||
70 | ||
71 | /************************************************* | |
72 | * Check for existence of file * | |
73 | *************************************************/ | |
74 | ||
75 | /* First of all, we stat the file. If this fails, we try to stat the enclosing | |
76 | directory, because a file in an unmounted NFS directory will look the same as a | |
77 | non-existent file. It seems that in Solaris 2.6, statting an entry in an | |
78 | indirect map that is currently unmounted does not cause the mount to happen. | |
79 | Instead, dummy data is returned, which defeats the whole point of this test. | |
80 | However, if a stat() is done on some object inside the directory, such as the | |
81 | "." back reference to itself, then the mount does occur. If an NFS host is | |
82 | taken offline, it is possible for the stat() to get stuck until it comes back. | |
83 | To guard against this, stick a timer round it. If we can't access the "." | |
84 | inside the directory, try the plain directory, just in case that helps. | |
85 | ||
86 | Argument: | |
87 | filename the file name | |
88 | error for message on error | |
89 | ||
90 | Returns: FILE_EXIST the file exists | |
91 | FILE_NOT_EXIST the file does not exist | |
92 | FILE_EXIST_UNCLEAR cannot determine existence | |
93 | */ | |
94 | ||
95 | static int | |
96 | rda_exists(uschar *filename, uschar **error) | |
97 | { | |
98 | int rc, saved_errno; | |
059ec3d9 | 99 | struct stat statbuf; |
f3ebb786 | 100 | uschar * s; |
059ec3d9 PH |
101 | |
102 | if ((rc = Ustat(filename, &statbuf)) >= 0) return FILE_EXIST; | |
103 | saved_errno = errno; | |
104 | ||
f3ebb786 | 105 | s = string_copy(filename); |
059ec3d9 PH |
106 | sigalrm_seen = FALSE; |
107 | ||
108 | if (saved_errno == ENOENT) | |
109 | { | |
f3ebb786 JH |
110 | uschar * slash = Ustrrchr(s, '/'); |
111 | Ustrcpy(slash+1, US"."); | |
059ec3d9 | 112 | |
c2a1bba0 | 113 | ALARM(30); |
f3ebb786 | 114 | rc = Ustat(s, &statbuf); |
059ec3d9 PH |
115 | if (rc != 0 && errno == EACCES && !sigalrm_seen) |
116 | { | |
117 | *slash = 0; | |
f3ebb786 | 118 | rc = Ustat(s, &statbuf); |
059ec3d9 PH |
119 | } |
120 | saved_errno = errno; | |
c2a1bba0 | 121 | ALARM_CLR(0); |
059ec3d9 | 122 | |
f3ebb786 | 123 | DEBUG(D_route) debug_printf("stat(%s)=%d\n", s, rc); |
059ec3d9 PH |
124 | } |
125 | ||
126 | if (sigalrm_seen || rc != 0) | |
127 | { | |
f3ebb786 JH |
128 | *error = string_sprintf("failed to stat %s (%s)", s, |
129 | sigalrm_seen? "timeout" : strerror(saved_errno)); | |
059ec3d9 PH |
130 | return FILE_EXIST_UNCLEAR; |
131 | } | |
132 | ||
133 | *error = string_sprintf("%s does not exist", filename); | |
134 | DEBUG(D_route) debug_printf("%s\n", *error); | |
135 | return FILE_NOT_EXIST; | |
136 | } | |
137 | ||
138 | ||
139 | ||
140 | /************************************************* | |
141 | * Get forwarding list from a file * | |
142 | *************************************************/ | |
143 | ||
144 | /* Open a file and read its entire contents into a block of memory. Certain | |
145 | opening errors are optionally treated the same as "file does not exist". | |
146 | ||
147 | ENOTDIR means that something along the line is not a directory: there are | |
148 | installations that set home directories to be /dev/null for non-login accounts | |
149 | but in normal circumstances this indicates some kind of configuration error. | |
150 | ||
151 | EACCES means there's a permissions failure. Some users turn off read permission | |
152 | on a .forward file to suspend forwarding, but this is probably an error in any | |
153 | kind of mailing list processing. | |
154 | ||
155 | The redirect block that contains the file name also contains constraints such | |
156 | as who may own the file, and mode bits that must not be set. This function is | |
157 | ||
158 | Arguments: | |
159 | rdata rdirect block, containing file name and constraints | |
160 | options for the RDO_ENOTDIR and RDO_EACCES options | |
161 | error where to put an error message | |
162 | yield what to return from rda_interpret on error | |
163 | ||
164 | Returns: pointer to string in store; NULL on error | |
165 | */ | |
166 | ||
167 | static uschar * | |
168 | rda_get_file_contents(redirect_block *rdata, int options, uschar **error, | |
169 | int *yield) | |
170 | { | |
171 | FILE *fwd; | |
172 | uschar *filebuf; | |
173 | uschar *filename = rdata->string; | |
174 | BOOL uid_ok = !rdata->check_owner; | |
175 | BOOL gid_ok = !rdata->check_group; | |
176 | struct stat statbuf; | |
177 | ||
178 | /* Attempt to open the file. If it appears not to exist, check up on the | |
179 | containing directory by statting it. If the directory does not exist, we treat | |
180 | this situation as an error (which will cause delivery to defer); otherwise we | |
181 | pass back FF_NONEXIST, which causes the redirect router to decline. | |
182 | ||
183 | However, if the ignore_enotdir option is set (to ignore "something on the | |
184 | path is not a directory" errors), the right behaviour seems to be not to do the | |
185 | directory test. */ | |
186 | ||
187 | fwd = Ufopen(filename, "rb"); | |
188 | if (fwd == NULL) | |
189 | { | |
190 | switch(errno) | |
191 | { | |
192 | case ENOENT: /* File does not exist */ | |
193 | DEBUG(D_route) debug_printf("%s does not exist\n%schecking parent directory\n", | |
194 | filename, | |
195 | ((options & RDO_ENOTDIR) != 0)? "ignore_enotdir set => skip " : ""); | |
196 | *yield = (((options & RDO_ENOTDIR) != 0) || | |
197 | rda_exists(filename, error) == FILE_NOT_EXIST)? | |
198 | FF_NONEXIST : FF_ERROR; | |
199 | return NULL; | |
200 | ||
201 | case ENOTDIR: /* Something on the path isn't a directory */ | |
202 | if ((options & RDO_ENOTDIR) == 0) goto DEFAULT_ERROR; | |
203 | DEBUG(D_route) debug_printf("non-directory on path %s: file assumed not to " | |
204 | "exist\n", filename); | |
205 | *yield = FF_NONEXIST; | |
206 | return NULL; | |
207 | ||
208 | case EACCES: /* Permission denied */ | |
209 | if ((options & RDO_EACCES) == 0) goto DEFAULT_ERROR; | |
210 | DEBUG(D_route) debug_printf("permission denied for %s: file assumed not to " | |
211 | "exist\n", filename); | |
212 | *yield = FF_NONEXIST; | |
213 | return NULL; | |
214 | ||
215 | DEFAULT_ERROR: | |
216 | default: | |
217 | *error = string_open_failed(errno, "%s", filename); | |
218 | *yield = FF_ERROR; | |
219 | return NULL; | |
220 | } | |
221 | } | |
222 | ||
223 | /* Check that we have a regular file. */ | |
224 | ||
225 | if (fstat(fileno(fwd), &statbuf) != 0) | |
226 | { | |
227 | *error = string_sprintf("failed to stat %s: %s", filename, strerror(errno)); | |
228 | goto ERROR_RETURN; | |
229 | } | |
230 | ||
231 | if ((statbuf.st_mode & S_IFMT) != S_IFREG) | |
232 | { | |
233 | *error = string_sprintf("%s is not a regular file", filename); | |
234 | goto ERROR_RETURN; | |
235 | } | |
236 | ||
237 | /* Check for unwanted mode bits */ | |
238 | ||
239 | if ((statbuf.st_mode & rdata->modemask) != 0) | |
240 | { | |
241 | *error = string_sprintf("bad mode (0%o) for %s: 0%o bit(s) unexpected", | |
242 | statbuf.st_mode, filename, statbuf.st_mode & rdata->modemask); | |
243 | goto ERROR_RETURN; | |
244 | } | |
245 | ||
246 | /* Check the file owner and file group if required to do so. */ | |
247 | ||
248 | if (!uid_ok) | |
249 | { | |
250 | if (rdata->pw != NULL && statbuf.st_uid == rdata->pw->pw_uid) | |
251 | uid_ok = TRUE; | |
252 | else if (rdata->owners != NULL) | |
d7978c0f | 253 | for (int i = 1; i <= (int)(rdata->owners[0]); i++) |
059ec3d9 | 254 | if (rdata->owners[i] == statbuf.st_uid) { uid_ok = TRUE; break; } |
059ec3d9 PH |
255 | } |
256 | ||
257 | if (!gid_ok) | |
258 | { | |
259 | if (rdata->pw != NULL && statbuf.st_gid == rdata->pw->pw_gid) | |
260 | gid_ok = TRUE; | |
261 | else if (rdata->owngroups != NULL) | |
d7978c0f | 262 | for (int i = 1; i <= (int)(rdata->owngroups[0]); i++) |
059ec3d9 | 263 | if (rdata->owngroups[i] == statbuf.st_gid) { gid_ok = TRUE; break; } |
059ec3d9 PH |
264 | } |
265 | ||
266 | if (!uid_ok || !gid_ok) | |
267 | { | |
268 | *error = string_sprintf("bad %s for %s", uid_ok? "group" : "owner", filename); | |
269 | goto ERROR_RETURN; | |
270 | } | |
271 | ||
272 | /* Put an upper limit on the size of the file, just to stop silly people | |
273 | feeding in ridiculously large files, which can easily be created by making | |
274 | files that have holes in them. */ | |
275 | ||
276 | if (statbuf.st_size > MAX_FILTER_SIZE) | |
277 | { | |
278 | *error = string_sprintf("%s is too big (max %d)", filename, MAX_FILTER_SIZE); | |
279 | goto ERROR_RETURN; | |
280 | } | |
281 | ||
282 | /* Read the file in one go in order to minimize the time we have it open. */ | |
283 | ||
f3ebb786 | 284 | filebuf = store_get(statbuf.st_size + 1, is_tainted(filename)); |
059ec3d9 PH |
285 | |
286 | if (fread(filebuf, 1, statbuf.st_size, fwd) != statbuf.st_size) | |
287 | { | |
288 | *error = string_sprintf("error while reading %s: %s", | |
289 | filename, strerror(errno)); | |
290 | goto ERROR_RETURN; | |
291 | } | |
292 | filebuf[statbuf.st_size] = 0; | |
293 | ||
059ec3d9 | 294 | DEBUG(D_route) |
b1c749bb | 295 | debug_printf(OFF_T_FMT " bytes read from %s\n", statbuf.st_size, filename); |
059ec3d9 | 296 | |
f1e894f3 | 297 | (void)fclose(fwd); |
059ec3d9 PH |
298 | return filebuf; |
299 | ||
300 | /* Return an error: the string is already set up. */ | |
301 | ||
302 | ERROR_RETURN: | |
303 | *yield = FF_ERROR; | |
f1e894f3 | 304 | (void)fclose(fwd); |
059ec3d9 PH |
305 | return NULL; |
306 | } | |
307 | ||
308 | ||
309 | ||
310 | /************************************************* | |
311 | * Extract info from list or filter * | |
312 | *************************************************/ | |
313 | ||
314 | /* This function calls the appropriate function to extract addresses from a | |
315 | forwarding list, or to run a filter file and get addresses from there. | |
316 | ||
317 | Arguments: | |
318 | rdata the redirection block | |
319 | options the options bits | |
320 | include_directory restrain to this directory | |
321 | sieve_vacation_directory passed to sieve_interpret | |
efd9a422 | 322 | sieve_enotify_mailto_owner passed to sieve_interpret |
e4a89c47 PH |
323 | sieve_useraddress passed to sieve_interpret |
324 | sieve_subaddress passed to sieve_interpret | |
059ec3d9 PH |
325 | generated where to hang generated addresses |
326 | error for error messages | |
327 | eblockp for details of skipped syntax errors | |
328 | (NULL => no skip) | |
329 | filtertype set to the filter type: | |
330 | FILTER_FORWARD => a traditional .forward file | |
331 | FILTER_EXIM => an Exim filter file | |
332 | FILTER_SIEVE => a Sieve filter file | |
333 | a system filter is always forced to be FILTER_EXIM | |
334 | ||
335 | Returns: a suitable return for rda_interpret() | |
336 | */ | |
337 | ||
338 | static int | |
339 | rda_extract(redirect_block *rdata, int options, uschar *include_directory, | |
efd9a422 MH |
340 | uschar *sieve_vacation_directory, uschar *sieve_enotify_mailto_owner, |
341 | uschar *sieve_useraddress, uschar *sieve_subaddress, | |
342 | address_item **generated, uschar **error, error_block **eblockp, | |
343 | int *filtertype) | |
059ec3d9 PH |
344 | { |
345 | uschar *data; | |
346 | ||
347 | if (rdata->isfile) | |
348 | { | |
91ecef39 | 349 | int yield = 0; |
059ec3d9 PH |
350 | data = rda_get_file_contents(rdata, options, error, &yield); |
351 | if (data == NULL) return yield; | |
352 | } | |
353 | else data = rdata->string; | |
354 | ||
8768d548 | 355 | *filtertype = f.system_filtering ? FILTER_EXIM : rda_is_filter(data); |
059ec3d9 PH |
356 | |
357 | /* Filter interpretation is done by a general function that is also called from | |
358 | the filter testing option (-bf). There are two versions: one for Exim filtering | |
359 | and one for Sieve filtering. Several features of string expansion may be locked | |
360 | out at sites that don't trust users. This is done by setting flags in | |
361 | expand_forbid that the expander inspects. */ | |
362 | ||
363 | if (*filtertype != FILTER_FORWARD) | |
364 | { | |
365 | int frc; | |
366 | int old_expand_forbid = expand_forbid; | |
367 | ||
23c7ff99 | 368 | DEBUG(D_route) debug_printf("data is %s filter program\n", |
f3ebb786 | 369 | *filtertype == FILTER_EXIM ? "an Exim" : "a Sieve"); |
23c7ff99 PH |
370 | |
371 | /* RDO_FILTER is an "allow" bit */ | |
8e669ac1 | 372 | |
059ec3d9 PH |
373 | if ((options & RDO_FILTER) == 0) |
374 | { | |
375 | *error = US"filtering not enabled"; | |
376 | return FF_ERROR; | |
377 | } | |
378 | ||
059ec3d9 | 379 | expand_forbid = |
f3ebb786 | 380 | expand_forbid & ~RDO_FILTER_EXPANSIONS | options & RDO_FILTER_EXPANSIONS; |
8e669ac1 | 381 | |
23c7ff99 | 382 | /* RDO_{EXIM,SIEVE}_FILTER are forbid bits */ |
8e669ac1 | 383 | |
23c7ff99 PH |
384 | if (*filtertype == FILTER_EXIM) |
385 | { | |
386 | if ((options & RDO_EXIM_FILTER) != 0) | |
387 | { | |
388 | *error = US"Exim filtering not enabled"; | |
389 | return FF_ERROR; | |
8e669ac1 | 390 | } |
23c7ff99 | 391 | frc = filter_interpret(data, options, generated, error); |
8e669ac1 | 392 | } |
23c7ff99 PH |
393 | else |
394 | { | |
395 | if ((options & RDO_SIEVE_FILTER) != 0) | |
396 | { | |
397 | *error = US"Sieve filtering not enabled"; | |
398 | return FF_ERROR; | |
399 | } | |
e4a89c47 | 400 | frc = sieve_interpret(data, options, sieve_vacation_directory, |
efd9a422 MH |
401 | sieve_enotify_mailto_owner, sieve_useraddress, sieve_subaddress, |
402 | generated, error); | |
8e669ac1 | 403 | } |
059ec3d9 PH |
404 | |
405 | expand_forbid = old_expand_forbid; | |
406 | return frc; | |
407 | } | |
408 | ||
409 | /* Not a filter script */ | |
410 | ||
411 | DEBUG(D_route) debug_printf("file is not a filter file\n"); | |
412 | ||
413 | return parse_forward_list(data, | |
414 | options, /* specials that are allowed */ | |
415 | generated, /* where to hang them */ | |
416 | error, /* for errors */ | |
417 | deliver_domain, /* to qualify \name */ | |
418 | include_directory, /* restrain to directory */ | |
419 | eblockp); /* for skipped syntax errors */ | |
420 | } | |
421 | ||
422 | ||
423 | ||
424 | ||
425 | /************************************************* | |
426 | * Write string down pipe * | |
427 | *************************************************/ | |
428 | ||
1ac6b2e7 | 429 | /* This function is used for transferring a string down a pipe between |
059ec3d9 PH |
430 | processes. If the pointer is NULL, a length of zero is written. |
431 | ||
432 | Arguments: | |
433 | fd the pipe | |
434 | s the string | |
435 | ||
1ac6b2e7 | 436 | Returns: -1 on error, else 0 |
059ec3d9 PH |
437 | */ |
438 | ||
1ac6b2e7 | 439 | static int |
55414b25 | 440 | rda_write_string(int fd, const uschar *s) |
059ec3d9 PH |
441 | { |
442 | int len = (s == NULL)? 0 : Ustrlen(s) + 1; | |
1ac6b2e7 JH |
443 | return ( write(fd, &len, sizeof(int)) != sizeof(int) |
444 | || (s != NULL && write(fd, s, len) != len) | |
445 | ) | |
446 | ? -1 : 0; | |
059ec3d9 PH |
447 | } |
448 | ||
449 | ||
450 | ||
451 | /************************************************* | |
452 | * Read string from pipe * | |
453 | *************************************************/ | |
454 | ||
455 | /* This function is used for receiving a string from a pipe. | |
456 | ||
457 | Arguments: | |
458 | fd the pipe | |
459 | sp where to put the string | |
460 | ||
461 | Returns: FALSE if data missing | |
462 | */ | |
463 | ||
464 | static BOOL | |
465 | rda_read_string(int fd, uschar **sp) | |
466 | { | |
467 | int len; | |
468 | ||
469 | if (read(fd, &len, sizeof(int)) != sizeof(int)) return FALSE; | |
d88f0784 JH |
470 | if (len == 0) |
471 | *sp = NULL; | |
472 | else | |
473 | /* We know we have enough memory so disable the error on "len" */ | |
474 | /* coverity[tainted_data] */ | |
f3ebb786 JH |
475 | /* We trust the data source, so untainted */ |
476 | if (read(fd, *sp = store_get(len, FALSE), len) != len) return FALSE; | |
059ec3d9 PH |
477 | return TRUE; |
478 | } | |
479 | ||
480 | ||
481 | ||
482 | /************************************************* | |
483 | * Interpret forward list or filter * | |
484 | *************************************************/ | |
485 | ||
486 | /* This function is passed a forward list string (unexpanded) or the name of a | |
487 | file (unexpanded) whose contents are the forwarding list. The list may in fact | |
488 | be a filter program if it starts with "#Exim filter" or "#Sieve filter". Other | |
aded2255 | 489 | types of filter, with different initial tag strings, may be introduced in due |
059ec3d9 PH |
490 | course. |
491 | ||
492 | The job of the function is to process the forwarding list or filter. It is | |
493 | pulled out into this separate function, because it is used for system filter | |
494 | files as well as from the redirect router. | |
495 | ||
496 | If the function is given a uid/gid, it runs a subprocess that passes the | |
497 | results back via a pipe. This provides security for things like :include:s in | |
498 | users' .forward files, and "logwrite" calls in users' filter files. A | |
499 | sub-process is NOT used when: | |
500 | ||
501 | . No uid/gid is provided | |
502 | . The input is a string which is not a filter string, and does not contain | |
503 | :include: | |
504 | . The input is a file whose non-existence can be detected in the main | |
505 | process (which is usually running as root). | |
506 | ||
507 | Arguments: | |
508 | rdata redirect data (file + constraints, or data string) | |
509 | options options to pass to the extraction functions, | |
510 | plus ENOTDIR and EACCES handling bits | |
511 | include_directory restrain :include: to this directory | |
efd9a422 MH |
512 | sieve_vacation_directory directory passed to sieve_interpret |
513 | sieve_enotify_mailto_owner passed to sieve_interpret | |
e4a89c47 PH |
514 | sieve_useraddress passed to sieve_interpret |
515 | sieve_subaddress passed to sieve_interpret | |
059ec3d9 PH |
516 | ugid uid/gid to run under - if NULL, no change |
517 | generated where to hang generated addresses, initially NULL | |
518 | error pointer for error message | |
519 | eblockp for skipped syntax errors; NULL if no skipping | |
520 | filtertype set to the type of file: | |
521 | FILTER_FORWARD => traditional .forward file | |
522 | FILTER_EXIM => an Exim filter file | |
523 | FILTER_SIEVE => a Sieve filter file | |
524 | a system filter is always forced to be FILTER_EXIM | |
525 | rname router name for error messages in the format | |
526 | "xxx router" or "system filter" | |
527 | ||
528 | Returns: values from extraction function, or FF_NONEXIST: | |
529 | FF_DELIVERED success, a significant action was taken | |
530 | FF_NOTDELIVERED success, no significant action | |
531 | FF_BLACKHOLE :blackhole: | |
532 | FF_DEFER defer requested | |
533 | FF_FAIL fail requested | |
534 | FF_INCLUDEFAIL some problem with :include: | |
535 | FF_FREEZE freeze requested | |
536 | FF_ERROR there was a problem | |
537 | FF_NONEXIST the file does not exist | |
538 | */ | |
539 | ||
540 | int | |
541 | rda_interpret(redirect_block *rdata, int options, uschar *include_directory, | |
efd9a422 MH |
542 | uschar *sieve_vacation_directory, uschar *sieve_enotify_mailto_owner, |
543 | uschar *sieve_useraddress, uschar *sieve_subaddress, ugid_block *ugid, | |
544 | address_item **generated, uschar **error, error_block **eblockp, | |
545 | int *filtertype, uschar *rname) | |
059ec3d9 PH |
546 | { |
547 | int fd, rc, pfd[2]; | |
548 | int yield, status; | |
549 | BOOL had_disaster = FALSE; | |
550 | pid_t pid; | |
551 | uschar *data; | |
552 | uschar *readerror = US""; | |
553 | void (*oldsignal)(int); | |
554 | ||
f3ebb786 JH |
555 | DEBUG(D_route) debug_printf("rda_interpret (%s): '%s'\n", |
556 | rdata->isfile ? "file" : "string", string_printing(rdata->string)); | |
059ec3d9 PH |
557 | |
558 | /* Do the expansions of the file name or data first, while still privileged. */ | |
559 | ||
f3ebb786 | 560 | if (!(data = expand_string(rdata->string))) |
059ec3d9 | 561 | { |
8768d548 | 562 | if (f.expand_string_forcedfail) return FF_NOTDELIVERED; |
059ec3d9 PH |
563 | *error = string_sprintf("failed to expand \"%s\": %s", rdata->string, |
564 | expand_string_message); | |
565 | return FF_ERROR; | |
566 | } | |
567 | rdata->string = data; | |
568 | ||
f3ebb786 | 569 | DEBUG(D_route) debug_printf("expanded: '%s'\n", data); |
059ec3d9 PH |
570 | |
571 | if (rdata->isfile && data[0] != '/') | |
572 | { | |
573 | *error = string_sprintf("\"%s\" is not an absolute path", data); | |
574 | return FF_ERROR; | |
575 | } | |
576 | ||
577 | /* If no uid/gid are supplied, or if we have a data string which does not start | |
578 | with #Exim filter or #Sieve filter, and does not contain :include:, do all the | |
579 | work in this process. Note that for a system filter, we always have a file, so | |
580 | the work is done in this process only if no user is supplied. */ | |
581 | ||
582 | if (!ugid->uid_set || /* Either there's no uid, or */ | |
583 | (!rdata->isfile && /* We've got the data, and */ | |
584 | rda_is_filter(data) == FILTER_FORWARD && /* It's not a filter script, */ | |
585 | Ustrstr(data, ":include:") == NULL)) /* and there's no :include: */ | |
586 | { | |
587 | return rda_extract(rdata, options, include_directory, | |
efd9a422 MH |
588 | sieve_vacation_directory, sieve_enotify_mailto_owner, sieve_useraddress, |
589 | sieve_subaddress, generated, error, eblockp, filtertype); | |
059ec3d9 PH |
590 | } |
591 | ||
592 | /* We need to run the processing code in a sub-process. However, if we can | |
593 | determine the non-existence of a file first, we can decline without having to | |
594 | create the sub-process. */ | |
595 | ||
596 | if (rdata->isfile && rda_exists(data, error) == FILE_NOT_EXIST) | |
597 | return FF_NONEXIST; | |
598 | ||
599 | /* If the file does exist, or we can't tell (non-root mounted NFS directory) | |
600 | we have to create the subprocess to do everything as the given user. The | |
601 | results of processing are passed back via a pipe. */ | |
602 | ||
603 | if (pipe(pfd) != 0) | |
604 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "creation of pipe for filter or " | |
605 | ":include: failed for %s: %s", rname, strerror(errno)); | |
606 | ||
607 | /* Ensure that SIGCHLD is set to SIG_DFL before forking, so that the child | |
608 | process can be waited for. We sometimes get here with it set otherwise. Save | |
af46795e PH |
609 | the old state for resetting on the wait. Ensure that all cached resources are |
610 | freed so that the subprocess starts with a clean slate and doesn't interfere | |
611 | with the parent process. */ | |
059ec3d9 PH |
612 | |
613 | oldsignal = signal(SIGCHLD, SIG_DFL); | |
af46795e PH |
614 | search_tidyup(); |
615 | ||
059ec3d9 PH |
616 | if ((pid = fork()) == 0) |
617 | { | |
618 | header_line *waslast = header_last; /* Save last header */ | |
619 | ||
620 | fd = pfd[pipe_write]; | |
f1e894f3 | 621 | (void)close(pfd[pipe_read]); |
059ec3d9 PH |
622 | exim_setugid(ugid->uid, ugid->gid, FALSE, rname); |
623 | ||
624 | /* Addresses can get rewritten in filters; if we are not root or the exim | |
625 | user (and we probably are not), turn off rewrite logging, because we cannot | |
626 | write to the log now. */ | |
627 | ||
628 | if (ugid->uid != root_uid && ugid->uid != exim_uid) | |
629 | { | |
630 | DEBUG(D_rewrite) debug_printf("turned off address rewrite logging (not " | |
631 | "root or exim in this process)\n"); | |
6c6d6e48 | 632 | BIT_CLEAR(log_selector, log_selector_size, Li_address_rewrite); |
059ec3d9 PH |
633 | } |
634 | ||
635 | /* Now do the business */ | |
636 | ||
637 | yield = rda_extract(rdata, options, include_directory, | |
efd9a422 MH |
638 | sieve_vacation_directory, sieve_enotify_mailto_owner, sieve_useraddress, |
639 | sieve_subaddress, generated, error, eblockp, filtertype); | |
059ec3d9 PH |
640 | |
641 | /* Pass back whether it was a filter, and the return code and any overall | |
642 | error text via the pipe. */ | |
643 | ||
1ac6b2e7 JH |
644 | if ( write(fd, filtertype, sizeof(int)) != sizeof(int) |
645 | || write(fd, &yield, sizeof(int)) != sizeof(int) | |
646 | || rda_write_string(fd, *error) != 0 | |
647 | ) | |
648 | goto bad; | |
059ec3d9 PH |
649 | |
650 | /* Pass back the contents of any syntax error blocks if we have a pointer */ | |
651 | ||
d7978c0f | 652 | if (eblockp) |
059ec3d9 | 653 | { |
d7978c0f | 654 | for (error_block * ep = *eblockp; ep; ep = ep->next) |
1ac6b2e7 JH |
655 | if ( rda_write_string(fd, ep->text1) != 0 |
656 | || rda_write_string(fd, ep->text2) != 0 | |
657 | ) | |
658 | goto bad; | |
659 | if (rda_write_string(fd, NULL) != 0) /* Indicates end of eblocks */ | |
660 | goto bad; | |
059ec3d9 PH |
661 | } |
662 | ||
663 | /* If this is a system filter, we have to pass back the numbers of any | |
664 | original header lines that were removed, and then any header lines that were | |
665 | added but not subsequently removed. */ | |
666 | ||
8768d548 | 667 | if (f.system_filtering) |
059ec3d9 PH |
668 | { |
669 | int i = 0; | |
d7978c0f | 670 | for (header_line * h = header_list; h != waslast->next; i++, h = h->next) |
1ac6b2e7 JH |
671 | if ( h->type == htype_old |
672 | && write(fd, &i, sizeof(i)) != sizeof(i) | |
673 | ) | |
674 | goto bad; | |
675 | ||
059ec3d9 | 676 | i = -1; |
1ac6b2e7 JH |
677 | if (write(fd, &i, sizeof(i)) != sizeof(i)) |
678 | goto bad; | |
059ec3d9 PH |
679 | |
680 | while (waslast != header_last) | |
681 | { | |
682 | waslast = waslast->next; | |
683 | if (waslast->type != htype_old) | |
1ac6b2e7 JH |
684 | if ( rda_write_string(fd, waslast->text) != 0 |
685 | || write(fd, &(waslast->type), sizeof(waslast->type)) | |
686 | != sizeof(waslast->type) | |
687 | ) | |
688 | goto bad; | |
059ec3d9 | 689 | } |
1ac6b2e7 JH |
690 | if (rda_write_string(fd, NULL) != 0) /* Indicates end of added headers */ |
691 | goto bad; | |
059ec3d9 PH |
692 | } |
693 | ||
694 | /* Write the contents of the $n variables */ | |
695 | ||
1ac6b2e7 JH |
696 | if (write(fd, filter_n, sizeof(filter_n)) != sizeof(filter_n)) |
697 | goto bad; | |
059ec3d9 PH |
698 | |
699 | /* If the result was DELIVERED or NOTDELIVERED, we pass back the generated | |
700 | addresses, and their associated information, through the pipe. This is | |
701 | just tedious, but it seems to be the only safe way. We do this also for | |
702 | FAIL and FREEZE, because a filter is allowed to set up deliveries that | |
703 | are honoured before freezing or failing. */ | |
704 | ||
705 | if (yield == FF_DELIVERED || yield == FF_NOTDELIVERED || | |
706 | yield == FF_FAIL || yield == FF_FREEZE) | |
707 | { | |
d7978c0f | 708 | for (address_item * addr = *generated; addr; addr = addr->next) |
059ec3d9 PH |
709 | { |
710 | int reply_options = 0; | |
25beaee4 | 711 | int ig_err = addr->prop.ignore_error ? 1 : 0; |
059ec3d9 | 712 | |
1ac6b2e7 | 713 | if ( rda_write_string(fd, addr->address) != 0 |
7eb0e5d2 JH |
714 | || write(fd, &addr->mode, sizeof(addr->mode)) != sizeof(addr->mode) |
715 | || write(fd, &addr->flags, sizeof(addr->flags)) != sizeof(addr->flags) | |
d43cbe25 | 716 | || rda_write_string(fd, addr->prop.errors_address) != 0 |
25beaee4 | 717 | || write(fd, &ig_err, sizeof(ig_err)) != sizeof(ig_err) |
1ac6b2e7 JH |
718 | ) |
719 | goto bad; | |
059ec3d9 | 720 | |
7eb0e5d2 | 721 | if (addr->pipe_expandn) |
d7978c0f | 722 | for (uschar ** pp = addr->pipe_expandn; *pp; pp++) |
1ac6b2e7 JH |
723 | if (rda_write_string(fd, *pp) != 0) |
724 | goto bad; | |
1ac6b2e7 JH |
725 | if (rda_write_string(fd, NULL) != 0) |
726 | goto bad; | |
059ec3d9 | 727 | |
7eb0e5d2 | 728 | if (!addr->reply) |
1ac6b2e7 JH |
729 | { |
730 | if (write(fd, &reply_options, sizeof(int)) != sizeof(int)) /* 0 means no reply */ | |
731 | goto bad; | |
732 | } | |
059ec3d9 PH |
733 | else |
734 | { | |
735 | reply_options |= REPLY_EXISTS; | |
736 | if (addr->reply->file_expand) reply_options |= REPLY_EXPAND; | |
737 | if (addr->reply->return_message) reply_options |= REPLY_RETURN; | |
1ac6b2e7 JH |
738 | if ( write(fd, &reply_options, sizeof(int)) != sizeof(int) |
739 | || write(fd, &(addr->reply->expand_forbid), sizeof(int)) | |
740 | != sizeof(int) | |
741 | || write(fd, &(addr->reply->once_repeat), sizeof(time_t)) | |
742 | != sizeof(time_t) | |
743 | || rda_write_string(fd, addr->reply->to) != 0 | |
744 | || rda_write_string(fd, addr->reply->cc) != 0 | |
745 | || rda_write_string(fd, addr->reply->bcc) != 0 | |
746 | || rda_write_string(fd, addr->reply->from) != 0 | |
747 | || rda_write_string(fd, addr->reply->reply_to) != 0 | |
748 | || rda_write_string(fd, addr->reply->subject) != 0 | |
749 | || rda_write_string(fd, addr->reply->headers) != 0 | |
750 | || rda_write_string(fd, addr->reply->text) != 0 | |
751 | || rda_write_string(fd, addr->reply->file) != 0 | |
752 | || rda_write_string(fd, addr->reply->logfile) != 0 | |
753 | || rda_write_string(fd, addr->reply->oncelog) != 0 | |
754 | ) | |
755 | goto bad; | |
059ec3d9 PH |
756 | } |
757 | } | |
758 | ||
1ac6b2e7 JH |
759 | if (rda_write_string(fd, NULL) != 0) /* Marks end of addresses */ |
760 | goto bad; | |
059ec3d9 PH |
761 | } |
762 | ||
af46795e PH |
763 | /* OK, this process is now done. Free any cached resources. Must use _exit() |
764 | and not exit() !! */ | |
059ec3d9 | 765 | |
1ac6b2e7 | 766 | out: |
f1e894f3 | 767 | (void)close(fd); |
af46795e | 768 | search_tidyup(); |
f3ebb786 | 769 | exim_underbar_exit(0); |
1ac6b2e7 JH |
770 | |
771 | bad: | |
772 | DEBUG(D_rewrite) debug_printf("rda_interpret: failed write to pipe\n"); | |
773 | goto out; | |
059ec3d9 PH |
774 | } |
775 | ||
776 | /* Back in the main process: panic if the fork did not succeed. */ | |
777 | ||
778 | if (pid < 0) | |
779 | log_write(0, LOG_MAIN|LOG_PANIC_DIE, "fork failed for %s", rname); | |
780 | ||
781 | /* Read the pipe to get the data from the filter/forward. Our copy of the | |
782 | writing end must be closed first, as otherwise read() won't return zero on an | |
783 | empty pipe. Afterwards, close the reading end. */ | |
784 | ||
f1e894f3 | 785 | (void)close(pfd[pipe_write]); |
059ec3d9 PH |
786 | |
787 | /* Read initial data, including yield and contents of *error */ | |
788 | ||
789 | fd = pfd[pipe_read]; | |
790 | if (read(fd, filtertype, sizeof(int)) != sizeof(int) || | |
791 | read(fd, &yield, sizeof(int)) != sizeof(int) || | |
792 | !rda_read_string(fd, error)) goto DISASTER; | |
793 | ||
059ec3d9 PH |
794 | /* Read the contents of any syntax error blocks if we have a pointer */ |
795 | ||
8cfd0f7b | 796 | if (eblockp) |
059ec3d9 | 797 | { |
059ec3d9 | 798 | error_block *e; |
d7978c0f | 799 | for (error_block ** p = eblockp; ; p = &e->next) |
059ec3d9 | 800 | { |
8cfd0f7b | 801 | uschar *s; |
059ec3d9 | 802 | if (!rda_read_string(fd, &s)) goto DISASTER; |
8cfd0f7b | 803 | if (!s) break; |
f3ebb786 | 804 | e = store_get(sizeof(error_block), FALSE); |
059ec3d9 PH |
805 | e->next = NULL; |
806 | e->text1 = s; | |
807 | if (!rda_read_string(fd, &s)) goto DISASTER; | |
808 | e->text2 = s; | |
809 | *p = e; | |
059ec3d9 PH |
810 | } |
811 | } | |
812 | ||
813 | /* If this is a system filter, read the identify of any original header lines | |
814 | that were removed, and then read data for any new ones that were added. */ | |
815 | ||
8768d548 | 816 | if (f.system_filtering) |
059ec3d9 PH |
817 | { |
818 | int hn = 0; | |
819 | header_line *h = header_list; | |
820 | ||
821 | for (;;) | |
822 | { | |
823 | int n; | |
824 | if (read(fd, &n, sizeof(int)) != sizeof(int)) goto DISASTER; | |
825 | if (n < 0) break; | |
826 | while (hn < n) | |
827 | { | |
828 | hn++; | |
8cfd0f7b | 829 | if (!(h = h->next)) goto DISASTER_NO_HEADER; |
059ec3d9 PH |
830 | } |
831 | h->type = htype_old; | |
832 | } | |
833 | ||
834 | for (;;) | |
835 | { | |
836 | uschar *s; | |
837 | int type; | |
838 | if (!rda_read_string(fd, &s)) goto DISASTER; | |
8cfd0f7b | 839 | if (!s) break; |
059ec3d9 PH |
840 | if (read(fd, &type, sizeof(type)) != sizeof(type)) goto DISASTER; |
841 | header_add(type, "%s", s); | |
842 | } | |
843 | } | |
844 | ||
845 | /* Read the values of the $n variables */ | |
846 | ||
847 | if (read(fd, filter_n, sizeof(filter_n)) != sizeof(filter_n)) goto DISASTER; | |
848 | ||
849 | /* If the yield is DELIVERED, NOTDELIVERED, FAIL, or FREEZE there may follow | |
850 | addresses and data to go with them. Keep them in the same order in the | |
851 | generated chain. */ | |
852 | ||
853 | if (yield == FF_DELIVERED || yield == FF_NOTDELIVERED || | |
854 | yield == FF_FAIL || yield == FF_FREEZE) | |
855 | { | |
856 | address_item **nextp = generated; | |
857 | ||
858 | for (;;) | |
859 | { | |
860 | int i, reply_options; | |
861 | address_item *addr; | |
862 | uschar *recipient; | |
863 | uschar *expandn[EXPAND_MAXN + 2]; | |
864 | ||
865 | /* First string is the address; NULL => end of addresses */ | |
866 | ||
867 | if (!rda_read_string(fd, &recipient)) goto DISASTER; | |
f3ebb786 | 868 | if (!recipient) break; |
059ec3d9 PH |
869 | |
870 | /* Hang on the end of the chain */ | |
871 | ||
872 | addr = deliver_make_addr(recipient, FALSE); | |
873 | *nextp = addr; | |
874 | nextp = &(addr->next); | |
875 | ||
876 | /* Next comes the mode and the flags fields */ | |
877 | ||
25beaee4 MK |
878 | if ( read(fd, &addr->mode, sizeof(addr->mode)) != sizeof(addr->mode) |
879 | || read(fd, &addr->flags, sizeof(addr->flags)) != sizeof(addr->flags) | |
880 | || !rda_read_string(fd, &addr->prop.errors_address) | |
881 | || read(fd, &i, sizeof(i)) != sizeof(i) | |
882 | ) | |
883 | goto DISASTER; | |
884 | addr->prop.ignore_error = (i != 0); | |
059ec3d9 PH |
885 | |
886 | /* Next comes a possible setting for $thisaddress and any numerical | |
887 | variables for pipe expansion, terminated by a NULL string. The maximum | |
888 | number of numericals is EXPAND_MAXN. Note that we put filter_thisaddress | |
889 | into the zeroth item in the vector - this is sorted out inside the pipe | |
890 | transport. */ | |
891 | ||
892 | for (i = 0; i < EXPAND_MAXN + 1; i++) | |
893 | { | |
894 | uschar *temp; | |
895 | if (!rda_read_string(fd, &temp)) goto DISASTER; | |
896 | if (i == 0) filter_thisaddress = temp; /* Just in case */ | |
897 | expandn[i] = temp; | |
898 | if (temp == NULL) break; | |
899 | } | |
900 | ||
901 | if (i > 0) | |
902 | { | |
f3ebb786 | 903 | addr->pipe_expandn = store_get((i+1) * sizeof(uschar *), FALSE); |
059ec3d9 PH |
904 | addr->pipe_expandn[i] = NULL; |
905 | while (--i >= 0) addr->pipe_expandn[i] = expandn[i]; | |
906 | } | |
907 | ||
908 | /* Then an int containing reply options; zero => no reply data. */ | |
909 | ||
910 | if (read(fd, &reply_options, sizeof(int)) != sizeof(int)) goto DISASTER; | |
911 | if ((reply_options & REPLY_EXISTS) != 0) | |
912 | { | |
f3ebb786 | 913 | addr->reply = store_get(sizeof(reply_item), FALSE); |
059ec3d9 PH |
914 | |
915 | addr->reply->file_expand = (reply_options & REPLY_EXPAND) != 0; | |
916 | addr->reply->return_message = (reply_options & REPLY_RETURN) != 0; | |
917 | ||
918 | if (read(fd,&(addr->reply->expand_forbid),sizeof(int)) != | |
919 | sizeof(int) || | |
920 | read(fd,&(addr->reply->once_repeat),sizeof(time_t)) != | |
921 | sizeof(time_t) || | |
922 | !rda_read_string(fd, &(addr->reply->to)) || | |
923 | !rda_read_string(fd, &(addr->reply->cc)) || | |
924 | !rda_read_string(fd, &(addr->reply->bcc)) || | |
925 | !rda_read_string(fd, &(addr->reply->from)) || | |
926 | !rda_read_string(fd, &(addr->reply->reply_to)) || | |
927 | !rda_read_string(fd, &(addr->reply->subject)) || | |
928 | !rda_read_string(fd, &(addr->reply->headers)) || | |
929 | !rda_read_string(fd, &(addr->reply->text)) || | |
930 | !rda_read_string(fd, &(addr->reply->file)) || | |
931 | !rda_read_string(fd, &(addr->reply->logfile)) || | |
932 | !rda_read_string(fd, &(addr->reply->oncelog))) | |
933 | goto DISASTER; | |
934 | } | |
935 | } | |
936 | } | |
937 | ||
938 | /* All data has been transferred from the sub-process. Reap it, close the | |
939 | reading end of the pipe, and we are done. */ | |
940 | ||
941 | WAIT_EXIT: | |
942 | while ((rc = wait(&status)) != pid) | |
943 | { | |
944 | if (rc < 0 && errno == ECHILD) /* Process has vanished */ | |
945 | { | |
946 | log_write(0, LOG_MAIN, "redirection process %d vanished unexpectedly", pid); | |
947 | goto FINAL_EXIT; | |
948 | } | |
949 | } | |
950 | ||
1921d2ea PH |
951 | DEBUG(D_route) |
952 | debug_printf("rda_interpret: subprocess yield=%d error=%s\n", yield, *error); | |
953 | ||
059ec3d9 PH |
954 | if (had_disaster) |
955 | { | |
956 | *error = string_sprintf("internal problem in %s: failure to transfer " | |
957 | "data from subprocess: status=%04x%s%s%s", rname, | |
958 | status, readerror, | |
959 | (*error == NULL)? US"" : US": error=", | |
960 | (*error == NULL)? US"" : *error); | |
961 | log_write(0, LOG_MAIN|LOG_PANIC, "%s", *error); | |
962 | } | |
963 | else if (status != 0) | |
964 | { | |
965 | log_write(0, LOG_MAIN|LOG_PANIC, "internal problem in %s: unexpected status " | |
966 | "%04x from redirect subprocess (but data correctly received)", rname, | |
967 | status); | |
968 | } | |
969 | ||
970 | FINAL_EXIT: | |
f1e894f3 | 971 | (void)close(fd); |
059ec3d9 PH |
972 | signal(SIGCHLD, oldsignal); /* restore */ |
973 | return yield; | |
974 | ||
975 | ||
976 | /* Come here if the data indicates removal of a header that we can't find */ | |
977 | ||
978 | DISASTER_NO_HEADER: | |
979 | readerror = US" readerror=bad header identifier"; | |
980 | had_disaster = TRUE; | |
981 | yield = FF_ERROR; | |
982 | goto WAIT_EXIT; | |
983 | ||
984 | /* Come here is there's a shambles in transferring the data over the pipe. The | |
985 | value of errno should still be set. */ | |
986 | ||
987 | DISASTER: | |
988 | readerror = string_sprintf(" readerror='%s'", strerror(errno)); | |
989 | had_disaster = TRUE; | |
990 | yield = FF_ERROR; | |
991 | goto WAIT_EXIT; | |
992 | } | |
993 | ||
994 | /* End of rda.c */ |