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059ec3d9 PH |
1 | /************************************************* |
2 | * Exim - an Internet mail transport agent * | |
3 | *************************************************/ | |
4 | ||
3386088d | 5 | /* Copyright (c) University of Cambridge 1995 - 2015 */ |
059ec3d9 PH |
6 | /* See the file NOTICE for conditions of use and distribution. */ |
7 | ||
8 | /* A set of functions to search databases in various formats. An open | |
9 | database is represented by a void * value which is returned from a lookup- | |
10 | specific "open" function. These are now all held in individual modules in the | |
11 | lookups subdirectory and the functions here form a generic interface. | |
12 | ||
13 | Caching is used to improve performance. Open files are cached until a tidyup | |
14 | function is called, and for each file the result of the last lookup is cached. | |
15 | However, if too many files are opened, some of those that are not in use have | |
16 | to be closed. Those open items that use real files are kept on a LRU chain to | |
17 | help with this. | |
18 | ||
19 | All the data is held in permanent store so as to be independent of the stacking | |
20 | pool that is reset from time to time. In fact, we use malloc'd store so that it | |
21 | can be freed when the caches are tidied up. It isn't actually clear whether | |
22 | this is a benefit or not, to be honest. */ | |
23 | ||
24 | #include "exim.h" | |
25 | ||
26 | ||
27 | /* Tree in which to cache open files until tidyup called. */ | |
28 | ||
29 | static tree_node *search_tree = NULL; | |
30 | ||
31 | /* Two-way chain of open databases that use real files. This is maintained in | |
32 | recently-used order for the purposes of closing the least recently used when | |
33 | too many files are open. */ | |
34 | ||
35 | static tree_node *open_top = NULL; | |
36 | static tree_node *open_bot = NULL; | |
37 | ||
38 | /* Count of open databases that use real files */ | |
39 | ||
40 | static int open_filecount = 0; | |
41 | ||
42 | /* Allow us to reset store used for lookups and lookup caching */ | |
43 | ||
f3ebb786 | 44 | static rmark search_reset_point = NULL; |
059ec3d9 PH |
45 | |
46 | ||
47 | ||
48 | /************************************************* | |
49 | * Validate a plain lookup type name * | |
50 | *************************************************/ | |
51 | ||
52 | /* Only those names that are recognized and whose code is included in the | |
53 | binary give an OK response. Use a binary chop search now that the list has got | |
54 | so long. | |
55 | ||
56 | Arguments: | |
57 | name lookup type name - not necessarily zero terminated (e.g. dbm*) | |
58 | len length of the name | |
59 | ||
60 | Returns: +ve => valid lookup name; value is offset in lookup_list | |
61 | -ve => invalid name; message in search_error_message. | |
62 | */ | |
63 | ||
64 | int | |
55414b25 | 65 | search_findtype(const uschar *name, int len) |
059ec3d9 PH |
66 | { |
67 | int bot = 0; | |
68 | int top = lookup_list_count; | |
69 | while (top > bot) | |
70 | { | |
71 | int mid = (top + bot)/2; | |
e6d225ae | 72 | int c = Ustrncmp(name, lookup_list[mid]->name, len); |
059ec3d9 PH |
73 | |
74 | /* If c == 0 we have matched the incoming name with the start of the search | |
75 | type name. However, some search types are substrings of others (e.g. nis and | |
76 | nisplus) so we need to check that the lengths are the same. The length of the | |
77 | type name cannot be shorter (else c would not be 0); if it is not equal it | |
78 | must be longer, and in that case, the incoming name comes before the name we | |
79 | are testing. By leaving c == 0 when the lengths are different, and doing a | |
80 | > 0 test below, this all falls out correctly. */ | |
81 | ||
e6d225ae | 82 | if (c == 0 && Ustrlen(lookup_list[mid]->name) == len) |
059ec3d9 | 83 | { |
e6d225ae | 84 | if (lookup_list[mid]->find != NULL) return mid; |
059ec3d9 PH |
85 | search_error_message = string_sprintf("lookup type \"%.*s\" is not " |
86 | "available (not in the binary - check buildtime LOOKUP configuration)", | |
87 | len, name); | |
88 | return -1; | |
89 | } | |
90 | ||
91 | if (c > 0) bot = mid + 1; else top = mid; | |
92 | } | |
93 | ||
94 | search_error_message = string_sprintf("unknown lookup type \"%.*s\"",len,name); | |
95 | return -1; | |
96 | } | |
97 | ||
98 | ||
99 | ||
100 | /************************************************* | |
101 | * Validate a full lookup type name * | |
102 | *************************************************/ | |
103 | ||
104 | /* This function recognizes the "partial-" prefix and also terminating * and *@ | |
105 | suffixes. | |
106 | ||
107 | Arguments: | |
108 | name the full lookup type name | |
109 | ptypeptr where to put the partial type | |
110 | after subtraction of 1024 or 2048: | |
111 | negative => no partial matching | |
112 | non-negative => minimum number of non-wild components | |
113 | ptypeaff where to put a pointer to the affix | |
114 | the affix is within name if supplied therein | |
115 | otherwise it's a literal string | |
116 | afflen the length of the affix | |
117 | starflags where to put the SEARCH_STAR and SEARCH_STARAT flags | |
118 | ||
119 | Returns: +ve => valid lookup name; value is offset in lookup_list | |
120 | -ve => invalid name; message in search_error_message. | |
121 | */ | |
122 | ||
123 | int | |
55414b25 | 124 | search_findtype_partial(const uschar *name, int *ptypeptr, const uschar **ptypeaff, |
059ec3d9 PH |
125 | int *afflen, int *starflags) |
126 | { | |
127 | int len, stype; | |
128 | int pv = -1; | |
55414b25 | 129 | const uschar *ss = name; |
059ec3d9 PH |
130 | |
131 | *starflags = 0; | |
132 | *ptypeaff = NULL; | |
133 | ||
134 | /* Check for a partial matching type. It must start with "partial", optionally | |
135 | followed by a sequence of digits. If this is followed by "-", the affix is the | |
136 | default "*." string. Otherwise we expect an affix in parentheses. Affixes are a | |
137 | limited number of characters, not including parens. */ | |
138 | ||
139 | if (Ustrncmp(name, "partial", 7) == 0) | |
140 | { | |
141 | ss += 7; | |
142 | if (isdigit (*ss)) | |
143 | { | |
144 | pv = 0; | |
145 | while (isdigit(*ss)) pv = pv*10 + *ss++ - '0'; | |
146 | } | |
147 | else pv = 2; /* Default number of wild components */ | |
148 | ||
149 | if (*ss == '(') | |
150 | { | |
151 | *ptypeaff = ++ss; | |
152 | while (ispunct(*ss) && *ss != ')') ss++; | |
153 | if (*ss != ')') goto BAD_TYPE; | |
154 | *afflen = ss++ - *ptypeaff; | |
155 | } | |
156 | else if (*ss++ == '-') | |
157 | { | |
158 | *ptypeaff = US "*."; | |
159 | *afflen = 2; | |
160 | } | |
161 | else | |
162 | { | |
163 | BAD_TYPE: | |
164 | search_error_message = string_sprintf("format error in lookup type \"%s\"", | |
165 | name); | |
166 | return -1; | |
167 | } | |
168 | } | |
169 | ||
170 | /* Now we are left with a lookup name, possibly followed by * or *@. */ | |
171 | ||
172 | len = Ustrlen(ss); | |
173 | if (len >= 2 && Ustrncmp(ss + len - 2, "*@", 2) == 0) | |
174 | { | |
175 | *starflags |= SEARCH_STARAT; | |
176 | len -= 2; | |
177 | } | |
178 | else if (len >= 1 && ss[len-1] == '*') | |
179 | { | |
180 | *starflags |= SEARCH_STAR; | |
181 | len--; | |
182 | } | |
183 | ||
184 | /* Check for the individual search type. Only those that are actually in the | |
d7837193 PH |
185 | binary are valid. For query-style types, "partial" and default types are |
186 | erroneous. */ | |
059ec3d9 PH |
187 | |
188 | stype = search_findtype(ss, len); | |
d7837193 | 189 | if (stype >= 0 && mac_islookup(stype, lookup_querystyle)) |
059ec3d9 | 190 | { |
d7837193 PH |
191 | if (pv >= 0) |
192 | { | |
193 | search_error_message = string_sprintf("\"partial\" is not permitted " | |
194 | "for lookup type \"%s\"", ss); | |
195 | return -1; | |
196 | } | |
197 | if ((*starflags & (SEARCH_STAR|SEARCH_STARAT)) != 0) | |
198 | { | |
199 | search_error_message = string_sprintf("defaults using \"*\" or \"*@\" are " | |
200 | "not permitted for lookup type \"%s\"", ss); | |
201 | return -1; | |
202 | } | |
059ec3d9 PH |
203 | } |
204 | ||
059ec3d9 PH |
205 | *ptypeptr = pv; |
206 | return stype; | |
207 | } | |
208 | ||
209 | ||
210 | ||
211 | /************************************************* | |
212 | * Release cached resources * | |
213 | *************************************************/ | |
214 | ||
215 | /* When search_open is called it caches the "file" that it opens in | |
216 | search_tree. The name of the tree node is a concatenation of the search type | |
217 | with the file name. For query-style lookups, the file name is empty. Real files | |
218 | are normally closed only when this tidyup routine is called, typically at the | |
219 | end of sections of code where a number of lookups might occur. However, if too | |
220 | many files are open simultaneously, some get closed beforehand. They can't be | |
221 | removed from the tree. There is also a general tidyup function which is called | |
222 | for the lookup driver, if it exists. | |
223 | ||
224 | First, there is an internal, recursive subroutine. | |
225 | ||
226 | Argument: a pointer to a search_openfile tree node | |
227 | Returns: nothing | |
228 | */ | |
229 | ||
230 | static void | |
231 | tidyup_subtree(tree_node *t) | |
232 | { | |
233 | search_cache *c = (search_cache *)(t->data.ptr); | |
234 | if (t->left != NULL) tidyup_subtree(t->left); | |
235 | if (t->right != NULL) tidyup_subtree(t->right); | |
236 | if (c != NULL && | |
237 | c->handle != NULL && | |
e6d225ae DW |
238 | lookup_list[c->search_type]->close != NULL) |
239 | lookup_list[c->search_type]->close(c->handle); | |
059ec3d9 PH |
240 | } |
241 | ||
242 | ||
243 | /* The external entry point | |
244 | ||
245 | Argument: none | |
246 | Returns: nothing | |
247 | */ | |
248 | ||
249 | void | |
250 | search_tidyup(void) | |
251 | { | |
059ec3d9 PH |
252 | int old_pool = store_pool; |
253 | ||
42c7f0b4 | 254 | DEBUG(D_lookup) debug_printf_indent("search_tidyup called\n"); |
059ec3d9 PH |
255 | |
256 | /* Close individually each cached open file. */ | |
257 | ||
258 | store_pool = POOL_SEARCH; | |
d7978c0f | 259 | if (search_tree) |
059ec3d9 PH |
260 | { |
261 | tidyup_subtree(search_tree); | |
262 | search_tree = NULL; | |
263 | } | |
264 | open_top = open_bot = NULL; | |
265 | open_filecount = 0; | |
266 | ||
267 | /* Call the general tidyup entry for any drivers that have one. */ | |
268 | ||
d7978c0f JH |
269 | for (int i = 0; i < lookup_list_count; i++) if (lookup_list[i]->tidy) |
270 | (lookup_list[i]->tidy)(); | |
059ec3d9 | 271 | |
f3ebb786 | 272 | if (search_reset_point) search_reset_point = store_reset(search_reset_point); |
059ec3d9 PH |
273 | store_pool = old_pool; |
274 | } | |
275 | ||
276 | ||
277 | ||
278 | ||
279 | /************************************************* | |
280 | * Open search database * | |
281 | *************************************************/ | |
282 | ||
283 | /* A mode, and lists of owners and groups, are passed over for checking in | |
284 | the cases where the database is one or more files. Return NULL, with a message | |
285 | pointed to by message, in cases of error. | |
286 | ||
287 | For search types that use a file or files, check up on the mode after | |
288 | opening. It is tempting to do a stat before opening the file, and use it as | |
289 | an existence check. However, doing that opens a small security loophole in | |
290 | that the status could be changed before the file is opened. Can't quite see | |
291 | what problems this might lead to, but you can't be too careful where security | |
292 | is concerned. Fstat() on an open file can normally be expected to succeed, | |
293 | but there are some NFS states where it does not. | |
294 | ||
295 | There are two styles of query: (1) in the "single-key+file" style, a single | |
296 | key string and a file name are given, for example, for linear searches, DBM | |
297 | files, or for NIS. (2) In the "query" style, no "filename" is given; instead | |
298 | just a single query string is passed. This applies to multiple-key lookup | |
299 | types such as NIS+. | |
300 | ||
301 | Before opening, scan the tree of cached files to see if this file is already | |
302 | open for the correct search type. If so, return the saved handle. If not, put | |
303 | the handle in the tree for possible subsequent use. See search_tidyup above for | |
304 | closing all the cached files. | |
305 | ||
306 | A count of open databases which use real files is maintained, and if this | |
307 | gets too large, we have to close a cached file. Its entry remains in the tree, | |
308 | but is marked closed. | |
309 | ||
310 | Arguments: | |
311 | filename the name of the file for single-key+file style lookups, | |
312 | NULL for query-style lookups | |
313 | search_type the type of search required | |
314 | modemask if a real single file is used, this specifies mode bits that | |
315 | must not be set; otherwise it is ignored | |
316 | owners if a real single file is used, this specifies the possible | |
317 | owners of the file; otherwise it is ignored | |
318 | owngroups if a real single file is used, this specifies the possible | |
319 | group owners of the file; otherwise it is ignored | |
320 | ||
321 | Returns: an identifying handle for the open database; | |
322 | this is the pointer to the tree block in the | |
323 | cache of open files; return NULL on open failure, with | |
324 | a message in search_error_message | |
325 | */ | |
326 | ||
327 | void * | |
328 | search_open(uschar *filename, int search_type, int modemask, uid_t *owners, | |
329 | gid_t *owngroups) | |
330 | { | |
331 | void *handle; | |
332 | tree_node *t; | |
333 | search_cache *c; | |
e6d225ae | 334 | lookup_info *lk = lookup_list[search_type]; |
059ec3d9 PH |
335 | uschar keybuffer[256]; |
336 | int old_pool = store_pool; | |
337 | ||
338 | /* Change to the search store pool and remember our reset point */ | |
339 | ||
340 | store_pool = POOL_SEARCH; | |
f3ebb786 | 341 | if (!search_reset_point) search_reset_point = store_mark(); |
059ec3d9 | 342 | |
42c7f0b4 JH |
343 | DEBUG(D_lookup) debug_printf_indent("search_open: %s \"%s\"\n", lk->name, |
344 | filename ? filename : US"NULL"); | |
059ec3d9 PH |
345 | |
346 | /* See if we already have this open for this type of search, and if so, | |
347 | pass back the tree block as the handle. The key for the tree node is the search | |
348 | type plus '0' concatenated with the file name. There may be entries in the tree | |
349 | with closed files if a lot of files have been opened. */ | |
350 | ||
351 | sprintf(CS keybuffer, "%c%.254s", search_type + '0', | |
df04890c | 352 | filename ? filename : US""); |
059ec3d9 | 353 | |
df04890c | 354 | if ((t = tree_search(search_tree, keybuffer))) |
059ec3d9 PH |
355 | { |
356 | c = (search_cache *)(t->data.ptr); | |
df04890c | 357 | if (c->handle) |
059ec3d9 | 358 | { |
42c7f0b4 | 359 | DEBUG(D_lookup) debug_printf_indent(" cached open\n"); |
059ec3d9 PH |
360 | store_pool = old_pool; |
361 | return t; | |
362 | } | |
42c7f0b4 | 363 | DEBUG(D_lookup) debug_printf_indent(" cached closed\n"); |
059ec3d9 PH |
364 | } |
365 | ||
366 | /* Otherwise, we need to open the file or database - each search type has its | |
367 | own code, which is now split off into separately compiled modules. Before doing | |
368 | this, if the search type is one that uses real files, check on the number that | |
369 | we are holding open in the cache. If the limit is reached, close the least | |
370 | recently used one. */ | |
371 | ||
372 | if (lk->type == lookup_absfile && open_filecount >= lookup_open_max) | |
373 | { | |
df04890c | 374 | if (!open_bot) |
059ec3d9 PH |
375 | log_write(0, LOG_MAIN|LOG_PANIC, "too many lookups open, but can't find " |
376 | "one to close"); | |
377 | else | |
378 | { | |
379 | search_cache *c = (search_cache *)(open_bot->data.ptr); | |
42c7f0b4 | 380 | DEBUG(D_lookup) debug_printf_indent("Too many lookup files open\n closing %s\n", |
059ec3d9 | 381 | open_bot->name); |
df04890c | 382 | if ((open_bot = c->up)) |
059ec3d9 PH |
383 | ((search_cache *)(open_bot->data.ptr))->down = NULL; |
384 | else | |
385 | open_top = NULL; | |
e6d225ae | 386 | ((lookup_list[c->search_type])->close)(c->handle); |
059ec3d9 PH |
387 | c->handle = NULL; |
388 | open_filecount--; | |
389 | } | |
390 | } | |
391 | ||
392 | /* If opening is successful, call the file-checking function if there is one, | |
393 | and if all is still well, enter the open database into the tree. */ | |
394 | ||
df04890c | 395 | if (!(handle = (lk->open)(filename, &search_error_message))) |
059ec3d9 PH |
396 | { |
397 | store_pool = old_pool; | |
398 | return NULL; | |
399 | } | |
400 | ||
df04890c JH |
401 | if ( lk->check |
402 | && !lk->check(handle, filename, modemask, owners, owngroups, | |
403 | &search_error_message)) | |
059ec3d9 PH |
404 | { |
405 | lk->close(handle); | |
406 | store_pool = old_pool; | |
407 | return NULL; | |
408 | } | |
409 | ||
410 | /* If this is a search type that uses real files, keep count. */ | |
411 | ||
412 | if (lk->type == lookup_absfile) open_filecount++; | |
413 | ||
414 | /* If we found a previously opened entry in the tree, re-use it; otherwise | |
415 | insert a new entry. On re-use, leave any cached lookup data and the lookup | |
416 | count alone. */ | |
417 | ||
df04890c | 418 | if (!t) |
059ec3d9 | 419 | { |
f3ebb786 JH |
420 | t = store_get(sizeof(tree_node) + Ustrlen(keybuffer), FALSE); |
421 | t->data.ptr = c = store_get(sizeof(search_cache), FALSE); | |
059ec3d9 PH |
422 | c->item_cache = NULL; |
423 | Ustrcpy(t->name, keybuffer); | |
424 | tree_insertnode(&search_tree, t); | |
425 | } | |
426 | else c = t->data.ptr; | |
427 | ||
428 | c->handle = handle; | |
429 | c->search_type = search_type; | |
430 | c->up = c->down = NULL; | |
431 | ||
432 | store_pool = old_pool; | |
433 | return t; | |
434 | } | |
435 | ||
436 | ||
437 | ||
438 | ||
439 | ||
440 | /************************************************* | |
441 | * Internal function: Find one item in database * | |
442 | *************************************************/ | |
443 | ||
444 | /* The answer is always put into dynamic store. The last lookup for each handle | |
445 | is cached. | |
446 | ||
447 | Arguments: | |
448 | handle the handle from search_open; points to tree node | |
449 | filename the filename that was handed to search_open, or | |
450 | NULL for query-style searches | |
451 | keystring the keystring for single-key+file lookups, or | |
452 | the querystring for query-style lookups | |
453 | ||
454 | Returns: a pointer to a dynamic string containing the answer, | |
455 | or NULL if the query failed or was deferred; in the | |
456 | latter case, search_find_defer is set TRUE; after an unusual | |
457 | failure, there may be a message in search_error_message. | |
458 | */ | |
459 | ||
460 | static uschar * | |
461 | internal_search_find(void *handle, uschar *filename, uschar *keystring) | |
462 | { | |
0488984d JH |
463 | tree_node * t = (tree_node *)handle; |
464 | search_cache * c = (search_cache *)(t->data.ptr); | |
465 | expiring_data * e = NULL; /* compiler quietening */ | |
466 | uschar * data = NULL; | |
059ec3d9 PH |
467 | int search_type = t->name[0] - '0'; |
468 | int old_pool = store_pool; | |
469 | ||
470 | /* Lookups that return DEFER may not always set an error message. So that | |
471 | the callers don't have to test for NULL, set an empty string. */ | |
472 | ||
473 | search_error_message = US""; | |
8768d548 | 474 | f.search_find_defer = FALSE; |
059ec3d9 | 475 | |
42c7f0b4 | 476 | DEBUG(D_lookup) debug_printf_indent("internal_search_find: file=\"%s\"\n " |
059ec3d9 | 477 | "type=%s key=\"%s\"\n", filename, |
e6d225ae | 478 | lookup_list[search_type]->name, keystring); |
059ec3d9 PH |
479 | |
480 | /* Insurance. If the keystring is empty, just fail. */ | |
481 | ||
482 | if (keystring[0] == 0) return NULL; | |
483 | ||
484 | /* Use the special store pool for search data */ | |
485 | ||
486 | store_pool = POOL_SEARCH; | |
487 | ||
488 | /* Look up the data for the key, unless it is already in the cache for this | |
489 | file. No need to check c->item_cache for NULL, tree_search will do so. */ | |
490 | ||
14b3c5bc JH |
491 | if ( (t = tree_search(c->item_cache, keystring)) |
492 | && (!(e = t->data.ptr)->expiry || e->expiry > time(NULL)) | |
493 | ) | |
494 | { /* Data was in the cache already; set the pointer from the tree node */ | |
7d8d08c4 | 495 | data = e->data.ptr; |
42c7f0b4 | 496 | DEBUG(D_lookup) debug_printf_indent("cached data used for lookup of %s%s%s\n", |
14b3c5bc JH |
497 | keystring, |
498 | filename ? US"\n in " : US"", filename ? filename : US""); | |
499 | } | |
500 | else | |
059ec3d9 | 501 | { |
14b3c5bc | 502 | uint do_cache = UINT_MAX; |
059ec3d9 PH |
503 | int keylength = Ustrlen(keystring); |
504 | ||
505 | DEBUG(D_lookup) | |
506 | { | |
42c7f0b4 JH |
507 | if (t) debug_printf_indent("cached data found but past valid time; "); |
508 | debug_printf_indent("%s lookup required for %s%s%s\n", | |
14b3c5bc JH |
509 | filename ? US"file" : US"database", |
510 | keystring, | |
511 | filename ? US"\n in " : US"", filename ? filename : US""); | |
059ec3d9 PH |
512 | } |
513 | ||
514 | /* Call the code for the different kinds of search. DEFER is handled | |
515 | like FAIL, except that search_find_defer is set so the caller can | |
516 | distinguish if necessary. */ | |
517 | ||
e6d225ae | 518 | if (lookup_list[search_type]->find(c->handle, filename, keystring, keylength, |
059ec3d9 | 519 | &data, &search_error_message, &do_cache) == DEFER) |
8768d548 | 520 | f.search_find_defer = TRUE; |
059ec3d9 PH |
521 | |
522 | /* A record that has been found is now in data, which is either NULL | |
523 | or points to a bit of dynamic store. Cache the result of the lookup if | |
524 | caching is permitted. Lookups can disable caching, when they did something | |
525 | that changes their data. The mysql and pgsql lookups do this when an | |
526 | UPDATE/INSERT query was executed. */ | |
527 | ||
528 | else if (do_cache) | |
529 | { | |
530 | int len = keylength + 1; | |
14b3c5bc JH |
531 | |
532 | if (t) /* Previous, out-of-date cache entry. Update with the */ | |
533 | { /* new result and forget the old one */ | |
534 | e->expiry = do_cache == UINT_MAX ? 0 : time(NULL)+do_cache; | |
7d8d08c4 | 535 | e->data.ptr = data; |
14b3c5bc JH |
536 | } |
537 | else | |
538 | { | |
f3ebb786 | 539 | e = store_get(sizeof(expiring_data) + sizeof(tree_node) + len, is_tainted(keystring)); |
14b3c5bc | 540 | e->expiry = do_cache == UINT_MAX ? 0 : time(NULL)+do_cache; |
7d8d08c4 | 541 | e->data.ptr = data; |
98b98887 | 542 | t = (tree_node *)(e+1); |
14b3c5bc JH |
543 | memcpy(t->name, keystring, len); |
544 | t->data.ptr = e; | |
545 | tree_insertnode(&c->item_cache, t); | |
546 | } | |
059ec3d9 PH |
547 | } |
548 | ||
549 | /* If caching was disabled, empty the cache tree. We just set the cache | |
550 | pointer to NULL here, because we cannot release the store at this stage. */ | |
551 | ||
552 | else | |
553 | { | |
42c7f0b4 | 554 | DEBUG(D_lookup) debug_printf_indent("lookup forced cache cleanup\n"); |
059ec3d9 PH |
555 | c->item_cache = NULL; |
556 | } | |
557 | } | |
558 | ||
059ec3d9 PH |
559 | DEBUG(D_lookup) |
560 | { | |
14b3c5bc | 561 | if (data) |
42c7f0b4 | 562 | debug_printf_indent("lookup yielded: %s\n", data); |
8768d548 | 563 | else if (f.search_find_defer) |
42c7f0b4 JH |
564 | debug_printf_indent("lookup deferred: %s\n", search_error_message); |
565 | else debug_printf_indent("lookup failed\n"); | |
059ec3d9 PH |
566 | } |
567 | ||
568 | /* Return it in new dynamic store in the regular pool */ | |
569 | ||
570 | store_pool = old_pool; | |
14b3c5bc | 571 | return data ? string_copy(data) : NULL; |
059ec3d9 PH |
572 | } |
573 | ||
574 | ||
575 | ||
576 | ||
577 | /************************************************* | |
578 | * Find one item in database, possibly wildcarded * | |
579 | *************************************************/ | |
580 | ||
581 | /* This function calls the internal function above; once only if there | |
582 | is no partial matching, but repeatedly when partial matching is requested. | |
583 | ||
584 | Arguments: | |
585 | handle the handle from search_open | |
586 | filename the filename that was handed to search_open, or | |
587 | NULL for query-style searches | |
588 | keystring the keystring for single-key+file lookups, or | |
589 | the querystring for query-style lookups | |
590 | partial -1 means no partial matching; | |
591 | otherwise it's the minimum number of components; | |
592 | affix the affix string for partial matching | |
593 | affixlen the length of the affix string | |
594 | starflags SEARCH_STAR and SEARCH_STARAT flags | |
595 | expand_setup pointer to offset for setting up expansion strings; | |
596 | don't do any if < 0 | |
597 | ||
598 | Returns: a pointer to a dynamic string containing the answer, | |
599 | or NULL if the query failed or was deferred; in the | |
600 | latter case, search_find_defer is set TRUE | |
601 | */ | |
602 | ||
603 | uschar * | |
604 | search_find(void *handle, uschar *filename, uschar *keystring, int partial, | |
55414b25 | 605 | const uschar *affix, int affixlen, int starflags, int *expand_setup) |
059ec3d9 PH |
606 | { |
607 | tree_node *t = (tree_node *)handle; | |
608 | BOOL set_null_wild = FALSE; | |
609 | uschar *yield; | |
610 | ||
611 | DEBUG(D_lookup) | |
612 | { | |
613 | if (partial < 0) affixlen = 99; /* So that "NULL" prints */ | |
42c7f0b4 | 614 | debug_printf_indent("search_find: file=\"%s\"\n key=\"%s\" " |
059ec3d9 PH |
615 | "partial=%d affix=%.*s starflags=%x\n", |
616 | (filename == NULL)? US"NULL" : filename, | |
617 | keystring, partial, affixlen, affix, starflags); | |
618 | } | |
619 | ||
620 | /* Arrange to put this database at the top of the LRU chain if it is a type | |
621 | that opens real files. */ | |
622 | ||
df04890c JH |
623 | if ( open_top != (tree_node *)handle |
624 | && lookup_list[t->name[0]-'0']->type == lookup_absfile) | |
059ec3d9 PH |
625 | { |
626 | search_cache *c = (search_cache *)(t->data.ptr); | |
627 | tree_node *up = c->up; | |
628 | tree_node *down = c->down; | |
629 | ||
630 | /* Cut it out of the list. A newly opened file will a NULL up pointer. | |
631 | Otherwise there will be a non-NULL up pointer, since we checked above that | |
632 | this block isn't already at the top of the list. */ | |
633 | ||
df04890c | 634 | if (up) |
059ec3d9 PH |
635 | { |
636 | ((search_cache *)(up->data.ptr))->down = down; | |
df04890c | 637 | if (down) |
059ec3d9 | 638 | ((search_cache *)(down->data.ptr))->up = up; |
df04890c JH |
639 | else |
640 | open_bot = up; | |
059ec3d9 PH |
641 | } |
642 | ||
643 | /* Now put it at the head of the list. */ | |
644 | ||
645 | c->up = NULL; | |
646 | c->down = open_top; | |
df04890c JH |
647 | if (!open_top) open_bot = t; |
648 | else ((search_cache *)(open_top->data.ptr))->up = t; | |
059ec3d9 PH |
649 | open_top = t; |
650 | } | |
651 | ||
652 | DEBUG(D_lookup) | |
653 | { | |
42c7f0b4 JH |
654 | debug_printf_indent("LRU list:\n"); |
655 | for (tree_node *t = open_top; t; ) | |
059ec3d9 PH |
656 | { |
657 | search_cache *c = (search_cache *)(t->data.ptr); | |
42c7f0b4 JH |
658 | debug_printf_indent(" %s\n", t->name); |
659 | if (t == open_bot) debug_printf_indent(" End\n"); | |
059ec3d9 PH |
660 | t = c->down; |
661 | } | |
662 | } | |
663 | ||
664 | /* First of all, try to match the key string verbatim. If matched a complete | |
665 | entry but could have been partial, flag to set up variables. */ | |
666 | ||
667 | yield = internal_search_find(handle, filename, keystring); | |
8768d548 | 668 | if (f.search_find_defer) return NULL; |
df04890c JH |
669 | |
670 | if (yield) { if (partial >= 0) set_null_wild = TRUE; } | |
059ec3d9 PH |
671 | |
672 | /* Not matched a complete entry; handle partial lookups, but only if the full | |
673 | search didn't defer. Don't use string_sprintf() to construct the initial key, | |
674 | just in case the original key is too long for the string_sprintf() buffer (it | |
675 | *has* happened!). The case of a zero-length affix has to be treated specially. | |
676 | */ | |
677 | ||
678 | else if (partial >= 0) | |
679 | { | |
680 | int len = Ustrlen(keystring); | |
681 | uschar *keystring2; | |
682 | ||
683 | /* Try with the affix on the front, except for a zero-length affix */ | |
684 | ||
685 | if (affixlen == 0) keystring2 = keystring; else | |
686 | { | |
f3ebb786 JH |
687 | keystring2 = store_get(len + affixlen + 1, |
688 | is_tainted(keystring) || is_tainted(affix)); | |
059ec3d9 PH |
689 | Ustrncpy(keystring2, affix, affixlen); |
690 | Ustrcpy(keystring2 + affixlen, keystring); | |
42c7f0b4 | 691 | DEBUG(D_lookup) debug_printf_indent("trying partial match %s\n", keystring2); |
059ec3d9 | 692 | yield = internal_search_find(handle, filename, keystring2); |
8768d548 | 693 | if (f.search_find_defer) return NULL; |
059ec3d9 PH |
694 | } |
695 | ||
696 | /* The key in its entirety did not match a wild entry; try chopping off | |
697 | leading components. */ | |
698 | ||
699 | if (yield == NULL) | |
700 | { | |
701 | int dotcount = 0; | |
702 | uschar *keystring3 = keystring2 + affixlen; | |
703 | uschar *s = keystring3; | |
704 | while (*s != 0) if (*s++ == '.') dotcount++; | |
705 | ||
706 | while (dotcount-- >= partial) | |
707 | { | |
708 | while (*keystring3 != 0 && *keystring3 != '.') keystring3++; | |
709 | ||
710 | /* If we get right to the end of the string (which will be the last time | |
711 | through this loop), we've failed if the affix is null. Otherwise do one | |
712 | last lookup for the affix itself, but if it is longer than 1 character, | |
713 | remove the last character if it is ".". */ | |
714 | ||
715 | if (*keystring3 == 0) | |
716 | { | |
717 | if (affixlen < 1) break; | |
718 | if (affixlen > 1 && affix[affixlen-1] == '.') affixlen--; | |
719 | Ustrncpy(keystring2, affix, affixlen); | |
720 | keystring2[affixlen] = 0; | |
721 | keystring3 = keystring2; | |
722 | } | |
723 | else | |
724 | { | |
725 | keystring3 -= affixlen - 1; | |
726 | if (affixlen > 0) Ustrncpy(keystring3, affix, affixlen); | |
727 | } | |
728 | ||
42c7f0b4 | 729 | DEBUG(D_lookup) debug_printf_indent("trying partial match %s\n", keystring3); |
059ec3d9 | 730 | yield = internal_search_find(handle, filename, keystring3); |
8768d548 | 731 | if (f.search_find_defer) return NULL; |
df04890c | 732 | if (yield) |
059ec3d9 PH |
733 | { |
734 | /* First variable is the wild part; second is the fixed part. Take care | |
735 | to get it right when keystring3 is just "*". */ | |
736 | ||
df04890c | 737 | if (expand_setup && *expand_setup >= 0) |
059ec3d9 PH |
738 | { |
739 | int fixedlength = Ustrlen(keystring3) - affixlen; | |
740 | int wildlength = Ustrlen(keystring) - fixedlength - 1; | |
741 | *expand_setup += 1; | |
742 | expand_nstring[*expand_setup] = keystring; | |
743 | expand_nlength[*expand_setup] = wildlength; | |
744 | *expand_setup += 1; | |
745 | expand_nstring[*expand_setup] = keystring + wildlength + 1; | |
746 | expand_nlength[*expand_setup] = (fixedlength < 0)? 0 : fixedlength; | |
747 | } | |
748 | break; | |
749 | } | |
750 | keystring3 += affixlen; | |
751 | } | |
752 | } | |
753 | ||
754 | else set_null_wild = TRUE; /* Matched a wild entry without any wild part */ | |
755 | } | |
756 | ||
757 | /* If nothing has been matched, but the option to look for "*@" is set, try | |
4c04137d | 758 | replacing everything to the left of @ by *. After a match, the wild part |
059ec3d9 PH |
759 | is set to the string to the left of the @. */ |
760 | ||
df04890c | 761 | if (!yield && starflags & SEARCH_STARAT) |
059ec3d9 PH |
762 | { |
763 | uschar *atat = Ustrrchr(keystring, '@'); | |
764 | if (atat != NULL && atat > keystring) | |
765 | { | |
766 | int savechar; | |
767 | savechar = *(--atat); | |
768 | *atat = '*'; | |
769 | ||
42c7f0b4 | 770 | DEBUG(D_lookup) debug_printf_indent("trying default match %s\n", atat); |
059ec3d9 PH |
771 | yield = internal_search_find(handle, filename, atat); |
772 | *atat = savechar; | |
8768d548 | 773 | if (f.search_find_defer) return NULL; |
059ec3d9 | 774 | |
df04890c | 775 | if (yield && expand_setup && *expand_setup >= 0) |
059ec3d9 PH |
776 | { |
777 | *expand_setup += 1; | |
778 | expand_nstring[*expand_setup] = keystring; | |
779 | expand_nlength[*expand_setup] = atat - keystring + 1; | |
780 | *expand_setup += 1; | |
781 | expand_nstring[*expand_setup] = keystring; | |
782 | expand_nlength[*expand_setup] = 0; | |
783 | } | |
784 | } | |
785 | } | |
786 | ||
787 | /* If we still haven't matched anything, and the option to look for "*" is set, | |
788 | try that. If we do match, the first variable (the wild part) is the whole key, | |
789 | and the second is empty. */ | |
790 | ||
df04890c | 791 | if (!yield && starflags & (SEARCH_STAR|SEARCH_STARAT)) |
059ec3d9 | 792 | { |
42c7f0b4 | 793 | DEBUG(D_lookup) debug_printf_indent("trying to match *\n"); |
059ec3d9 | 794 | yield = internal_search_find(handle, filename, US"*"); |
df04890c | 795 | if (yield && expand_setup && *expand_setup >= 0) |
059ec3d9 PH |
796 | { |
797 | *expand_setup += 1; | |
798 | expand_nstring[*expand_setup] = keystring; | |
799 | expand_nlength[*expand_setup] = Ustrlen(keystring); | |
800 | *expand_setup += 1; | |
801 | expand_nstring[*expand_setup] = keystring; | |
802 | expand_nlength[*expand_setup] = 0; | |
803 | } | |
804 | } | |
805 | ||
806 | /* If this was a potentially partial lookup, and we matched either a | |
807 | complete non-wild domain entry, or we matched a wild-carded entry without | |
808 | chopping off any of the domain components, set up the expansion variables | |
809 | (if required) so that the first one is empty, and the second one is the | |
810 | fixed part of the domain. The set_null_wild flag is set only when yield is not | |
811 | NULL. */ | |
812 | ||
df04890c | 813 | if (set_null_wild && expand_setup && *expand_setup >= 0) |
059ec3d9 PH |
814 | { |
815 | *expand_setup += 1; | |
816 | expand_nstring[*expand_setup] = keystring; | |
817 | expand_nlength[*expand_setup] = 0; | |
818 | *expand_setup += 1; | |
819 | expand_nstring[*expand_setup] = keystring; | |
820 | expand_nlength[*expand_setup] = Ustrlen(keystring); | |
821 | } | |
822 | ||
823 | return yield; | |
824 | } | |
825 | ||
826 | /* End of search.c */ |