Commit | Line | Data |
---|---|---|
c55a77db PH |
1 | /************************************************* |
2 | * fakens - A Fake Nameserver Program * | |
3 | *************************************************/ | |
4 | ||
5 | /* This program exists to support the testing of DNS handling code in Exim. It | |
6 | avoids the need to install special zones in a real nameserver. When Exim is | |
7 | running in its (new) test harness, DNS lookups are first passed to this program | |
8 | instead of to the real resolver. (With a few exceptions - see the discussion in | |
9 | the test suite's README file.) The program is also passed the name of the Exim | |
5f3d0983 HSHR |
10 | spool directory; it expects to find its "zone files" in dnszones relative to |
11 | exim config_main_directory. Note that there is little checking in this program. The fake | |
c55a77db PH |
12 | zone files are assumed to be syntactically valid. |
13 | ||
14 | The zones that are handled are found by scanning the dnszones directory. A file | |
15 | whose name is of the form db.ip4.x is a zone file for .x.in-addr.arpa; a file | |
16 | whose name is of the form db.ip6.x is a zone file for .x.ip6.arpa; a file of | |
17 | the form db.anything.else is a zone file for .anything.else. A file of the form | |
18 | qualify.x.y specifies the domain that is used to qualify single-component | |
19 | names, except for the name "dontqualify". | |
20 | ||
21 | The arguments to the program are: | |
22 | ||
23 | the name of the Exim spool directory | |
24 | the domain name that is being sought | |
25 | the DNS record type that is being sought | |
26 | ||
27 | The output from the program is written to stdout. It is supposed to be in | |
28 | exactly the same format as a traditional namserver response (see RFC 1035) so | |
29 | that Exim can process it as normal. At present, no compression is used. | |
30 | Error messages are written to stderr. | |
31 | ||
32 | The return codes from the program are zero for success, and otherwise the | |
33 | values that are set in h_errno after a failing call to the normal resolver: | |
34 | ||
35 | 1 HOST_NOT_FOUND host not found (authoritative) | |
36 | 2 TRY_AGAIN server failure | |
37 | 3 NO_RECOVERY non-recoverable error | |
38 | 4 NO_DATA valid name, no data of requested type | |
39 | ||
40 | In a real nameserver, TRY_AGAIN is also used for a non-authoritative not found, | |
41 | but it is not used for that here. There is also one extra return code: | |
42 | ||
43 | 5 PASS_ON requests Exim to call res_search() | |
44 | ||
45 | This is used for zones that fakens does not recognize. It is also used if a | |
46 | line in the zone file contains exactly this: | |
47 | ||
48 | PASS ON NOT FOUND | |
49 | ||
50 | and the domain is not found. It converts the the result to PASS_ON instead of | |
4d4c2a9b JH |
51 | HOST_NOT_FOUND. |
52 | ||
846430d9 JH |
53 | Any DNS record line in a zone file can be prefixed with "DELAY=" and |
54 | a number of milliseconds (followed by whitespace). | |
55 | ||
4d4c2a9b JH |
56 | Any DNS record line in a zone file can be prefixed with "DNSSEC" and |
57 | at least one space; if all the records found by a lookup are marked | |
58 | as such then the response will have the "AD" bit set. */ | |
c55a77db PH |
59 | |
60 | #include <ctype.h> | |
61 | #include <stdarg.h> | |
62 | #include <stdio.h> | |
e265af1f | 63 | #include <stdlib.h> |
c55a77db PH |
64 | #include <string.h> |
65 | #include <netdb.h> | |
66 | #include <errno.h> | |
9d787f10 | 67 | #include <signal.h> |
c55a77db PH |
68 | #include <arpa/nameser.h> |
69 | #include <sys/types.h> | |
846430d9 | 70 | #include <sys/time.h> |
c55a77db PH |
71 | #include <dirent.h> |
72 | ||
73 | #define FALSE 0 | |
74 | #define TRUE 1 | |
75 | #define PASS_ON 5 | |
76 | ||
77 | typedef int BOOL; | |
78 | typedef unsigned char uschar; | |
79 | ||
80 | #define CS (char *) | |
81 | #define CCS (const char *) | |
82 | #define US (unsigned char *) | |
83 | ||
84 | #define Ustrcat(s,t) strcat(CS(s),CCS(t)) | |
85 | #define Ustrchr(s,n) US strchr(CCS(s),n) | |
86 | #define Ustrcmp(s,t) strcmp(CCS(s),CCS(t)) | |
87 | #define Ustrcpy(s,t) strcpy(CS(s),CCS(t)) | |
88 | #define Ustrlen(s) (int)strlen(CCS(s)) | |
89 | #define Ustrncmp(s,t,n) strncmp(CCS(s),CCS(t),n) | |
90 | #define Ustrncpy(s,t,n) strncpy(CS(s),CCS(t),n) | |
91 | ||
c55a77db PH |
92 | typedef struct zoneitem { |
93 | uschar *zone; | |
94 | uschar *zonefile; | |
95 | } zoneitem; | |
96 | ||
97 | typedef struct tlist { | |
98 | uschar *name; | |
99 | int value; | |
100 | } tlist; | |
101 | ||
102 | /* On some (older?) operating systems, the standard ns_t_xxx definitions are | |
103 | not available, and only the older T_xxx ones exist in nameser.h. If ns_t_a is | |
104 | not defined, assume we are in this state. A really old system might not even | |
105 | know about AAAA and SRV at all. */ | |
106 | ||
107 | #ifndef ns_t_a | |
b4161d10 JH |
108 | # define ns_t_a T_A |
109 | # define ns_t_ns T_NS | |
110 | # define ns_t_cname T_CNAME | |
111 | # define ns_t_soa T_SOA | |
112 | # define ns_t_ptr T_PTR | |
113 | # define ns_t_mx T_MX | |
114 | # define ns_t_txt T_TXT | |
115 | # define ns_t_aaaa T_AAAA | |
116 | # define ns_t_srv T_SRV | |
117 | # define ns_t_tlsa T_TLSA | |
118 | # ifndef T_AAAA | |
119 | # define T_AAAA 28 | |
120 | # endif | |
121 | # ifndef T_SRV | |
122 | # define T_SRV 33 | |
123 | # endif | |
124 | # ifndef T_TLSA | |
125 | # define T_TLSA 52 | |
126 | # endif | |
c55a77db PH |
127 | #endif |
128 | ||
129 | static tlist type_list[] = { | |
130 | { US"A", ns_t_a }, | |
131 | { US"NS", ns_t_ns }, | |
132 | { US"CNAME", ns_t_cname }, | |
d2a2c69b | 133 | { US"SOA", ns_t_soa }, |
c55a77db PH |
134 | { US"PTR", ns_t_ptr }, |
135 | { US"MX", ns_t_mx }, | |
136 | { US"TXT", ns_t_txt }, | |
137 | { US"AAAA", ns_t_aaaa }, | |
138 | { US"SRV", ns_t_srv }, | |
b4161d10 | 139 | { US"TLSA", ns_t_tlsa }, |
c55a77db PH |
140 | { NULL, 0 } |
141 | }; | |
142 | ||
143 | ||
144 | ||
145 | /************************************************* | |
146 | * Get memory and sprintf into it * | |
147 | *************************************************/ | |
148 | ||
149 | /* This is used when building a table of zones and their files. | |
150 | ||
151 | Arguments: | |
152 | format a format string | |
153 | ... arguments | |
154 | ||
155 | Returns: pointer to formatted string | |
156 | */ | |
157 | ||
158 | static uschar * | |
159 | fcopystring(uschar *format, ...) | |
160 | { | |
161 | uschar *yield; | |
162 | char buffer[256]; | |
163 | va_list ap; | |
164 | va_start(ap, format); | |
e265af1f | 165 | vsprintf(buffer, CS format, ap); |
c55a77db PH |
166 | va_end(ap); |
167 | yield = (uschar *)malloc(Ustrlen(buffer) + 1); | |
168 | Ustrcpy(yield, buffer); | |
169 | return yield; | |
170 | } | |
171 | ||
172 | ||
173 | /************************************************* | |
174 | * Pack name into memory * | |
175 | *************************************************/ | |
176 | ||
177 | /* This function packs a domain name into memory according to DNS rules. At | |
178 | present, it doesn't do any compression. | |
179 | ||
180 | Arguments: | |
181 | name the name | |
182 | pk where to put it | |
183 | ||
184 | Returns: the updated value of pk | |
185 | */ | |
186 | ||
187 | static uschar * | |
188 | packname(uschar *name, uschar *pk) | |
189 | { | |
190 | while (*name != 0) | |
191 | { | |
192 | uschar *p = name; | |
193 | while (*p != 0 && *p != '.') p++; | |
194 | *pk++ = (p - name); | |
195 | memmove(pk, name, p - name); | |
196 | pk += p - name; | |
197 | name = (*p == 0)? p : p + 1; | |
198 | } | |
199 | *pk++ = 0; | |
200 | return pk; | |
201 | } | |
202 | ||
36b894a6 JH |
203 | uschar * |
204 | bytefield(uschar ** pp, uschar * pk) | |
205 | { | |
206 | unsigned value = 0; | |
207 | uschar * p = *pp; | |
208 | ||
209 | while (isdigit(*p)) value = value*10 + *p++ - '0'; | |
210 | while (isspace(*p)) p++; | |
211 | *pp = p; | |
212 | *pk++ = value & 255; | |
213 | return pk; | |
214 | } | |
215 | ||
b4161d10 JH |
216 | uschar * |
217 | shortfield(uschar ** pp, uschar * pk) | |
218 | { | |
219 | unsigned value = 0; | |
220 | uschar * p = *pp; | |
221 | ||
222 | while (isdigit(*p)) value = value*10 + *p++ - '0'; | |
223 | while (isspace(*p)) p++; | |
224 | *pp = p; | |
225 | *pk++ = (value >> 8) & 255; | |
226 | *pk++ = value & 255; | |
227 | return pk; | |
228 | } | |
229 | ||
d2a2c69b JH |
230 | uschar * |
231 | longfield(uschar ** pp, uschar * pk) | |
232 | { | |
233 | unsigned long value = 0; | |
234 | uschar * p = *pp; | |
235 | ||
236 | while (isdigit(*p)) value = value*10 + *p++ - '0'; | |
237 | while (isspace(*p)) p++; | |
238 | *pp = p; | |
239 | *pk++ = (value >> 24) & 255; | |
240 | *pk++ = (value >> 16) & 255; | |
241 | *pk++ = (value >> 8) & 255; | |
242 | *pk++ = value & 255; | |
243 | return pk; | |
244 | } | |
245 | ||
c55a77db PH |
246 | |
247 | ||
846430d9 JH |
248 | /*************************************************/ |
249 | ||
250 | static void | |
251 | milliwait(struct itimerval *itval) | |
252 | { | |
253 | sigset_t sigmask; | |
254 | sigset_t old_sigmask; | |
255 | ||
256 | if (itval->it_value.tv_usec < 100 && itval->it_value.tv_sec == 0) | |
257 | return; | |
258 | (void)sigemptyset(&sigmask); /* Empty mask */ | |
259 | (void)sigaddset(&sigmask, SIGALRM); /* Add SIGALRM */ | |
260 | (void)sigprocmask(SIG_BLOCK, &sigmask, &old_sigmask); /* Block SIGALRM */ | |
261 | (void)setitimer(ITIMER_REAL, itval, NULL); /* Start timer */ | |
262 | (void)sigfillset(&sigmask); /* All signals */ | |
263 | (void)sigdelset(&sigmask, SIGALRM); /* Remove SIGALRM */ | |
264 | (void)sigsuspend(&sigmask); /* Until SIGALRM */ | |
265 | (void)sigprocmask(SIG_SETMASK, &old_sigmask, NULL); /* Restore mask */ | |
266 | } | |
267 | ||
268 | static void | |
269 | millisleep(int msec) | |
270 | { | |
271 | struct itimerval itval; | |
272 | itval.it_interval.tv_sec = 0; | |
273 | itval.it_interval.tv_usec = 0; | |
274 | itval.it_value.tv_sec = msec/1000; | |
275 | itval.it_value.tv_usec = (msec % 1000) * 1000; | |
276 | milliwait(&itval); | |
277 | } | |
278 | ||
279 | ||
c55a77db PH |
280 | /************************************************* |
281 | * Scan file for RRs * | |
282 | *************************************************/ | |
283 | ||
284 | /* This function scans an open "zone file" for appropriate records, and adds | |
285 | any that are found to the output buffer. | |
286 | ||
287 | Arguments: | |
288 | f the input FILE | |
289 | zone the current zone name | |
290 | domain the domain we are looking for | |
291 | qtype the type of RR we want | |
292 | qtypelen the length of qtype | |
293 | pkptr points to the output buffer pointer; this is updated | |
294 | countptr points to the record count; this is updated | |
c55a77db PH |
295 | |
296 | Returns: 0 on success, else HOST_NOT_FOUND or NO_DATA or NO_RECOVERY or | |
297 | PASS_ON - the latter if a "PASS ON NOT FOUND" line is seen | |
298 | */ | |
299 | ||
300 | static int | |
301 | find_records(FILE *f, uschar *zone, uschar *domain, uschar *qtype, | |
4d4c2a9b | 302 | int qtypelen, uschar **pkptr, int *countptr, BOOL * dnssec) |
c55a77db PH |
303 | { |
304 | int yield = HOST_NOT_FOUND; | |
c55a77db PH |
305 | int domainlen = Ustrlen(domain); |
306 | BOOL pass_on_not_found = FALSE; | |
307 | tlist *typeptr; | |
308 | uschar *pk = *pkptr; | |
309 | uschar buffer[256]; | |
310 | uschar rrdomain[256]; | |
75e0e026 | 311 | uschar RRdomain[256]; |
c55a77db PH |
312 | |
313 | /* Decode the required type */ | |
314 | ||
315 | for (typeptr = type_list; typeptr->name != NULL; typeptr++) | |
316 | { if (Ustrcmp(typeptr->name, qtype) == 0) break; } | |
317 | if (typeptr->name == NULL) | |
318 | { | |
319 | fprintf(stderr, "fakens: unknown record type %s\n", qtype); | |
320 | return NO_RECOVERY; | |
321 | } | |
322 | ||
323 | rrdomain[0] = 0; /* No previous domain */ | |
324 | (void)fseek(f, 0, SEEK_SET); /* Start again at the beginning */ | |
325 | ||
b4161d10 | 326 | *dnssec = TRUE; /* cancelled by first nonsecure rec found */ |
4d4c2a9b | 327 | |
c55a77db PH |
328 | /* Scan for RRs */ |
329 | ||
330 | while (fgets(CS buffer, sizeof(buffer), f) != NULL) | |
331 | { | |
332 | uschar *rdlptr; | |
333 | uschar *p, *ep, *pp; | |
334 | BOOL found_cname = FALSE; | |
d2a2c69b | 335 | int i, value; |
c55a77db PH |
336 | int tvalue = typeptr->value; |
337 | int qtlen = qtypelen; | |
4d4c2a9b | 338 | BOOL rr_sec = FALSE; |
846430d9 | 339 | int delay = 0; |
c55a77db PH |
340 | |
341 | p = buffer; | |
342 | while (isspace(*p)) p++; | |
343 | if (*p == 0 || *p == ';') continue; | |
344 | ||
4d4c2a9b | 345 | if (Ustrncmp(p, US"PASS ON NOT FOUND", 17) == 0) |
c55a77db PH |
346 | { |
347 | pass_on_not_found = TRUE; | |
348 | continue; | |
349 | } | |
350 | ||
351 | ep = buffer + Ustrlen(buffer); | |
352 | while (isspace(ep[-1])) ep--; | |
353 | *ep = 0; | |
354 | ||
355 | p = buffer; | |
846430d9 | 356 | for (;;) |
1fb7660f JH |
357 | { |
358 | if (Ustrncmp(p, US"DNSSEC ", 7) == 0) /* tagged as secure */ | |
359 | { | |
360 | rr_sec = TRUE; | |
361 | p += 7; | |
362 | } | |
363 | else if (Ustrncmp(p, US"DELAY=", 6) == 0) /* delay before response */ | |
364 | { | |
365 | for (p += 6; *p >= '0' && *p <= '9'; p++) delay = delay*10 + *p - '0'; | |
366 | while (isspace(*p)) p++; | |
367 | } | |
368 | else | |
369 | break; | |
370 | } | |
4d4c2a9b | 371 | |
c55a77db PH |
372 | if (!isspace(*p)) |
373 | { | |
374 | uschar *pp = rrdomain; | |
75e0e026 PH |
375 | uschar *PP = RRdomain; |
376 | while (!isspace(*p)) | |
377 | { | |
378 | *pp++ = tolower(*p); | |
379 | *PP++ = *p++; | |
380 | } | |
381 | if (pp[-1] != '.') | |
382 | { | |
383 | Ustrcpy(pp, zone); | |
384 | Ustrcpy(PP, zone); | |
385 | } | |
386 | else | |
387 | { | |
388 | pp[-1] = 0; | |
389 | PP[-1] = 0; | |
390 | } | |
c55a77db PH |
391 | } |
392 | ||
393 | /* Compare domain names; first check for a wildcard */ | |
394 | ||
395 | if (rrdomain[0] == '*') | |
396 | { | |
397 | int restlen = Ustrlen(rrdomain) - 1; | |
398 | if (domainlen > restlen && | |
399 | Ustrcmp(domain + domainlen - restlen, rrdomain + 1) != 0) continue; | |
400 | } | |
401 | ||
402 | /* Not a wildcard RR */ | |
403 | ||
404 | else if (Ustrcmp(domain, rrdomain) != 0) continue; | |
405 | ||
406 | /* The domain matches */ | |
407 | ||
408 | if (yield == HOST_NOT_FOUND) yield = NO_DATA; | |
409 | ||
410 | /* Compare RR types; a CNAME record is always returned */ | |
411 | ||
412 | while (isspace(*p)) p++; | |
413 | ||
414 | if (Ustrncmp(p, "CNAME", 5) == 0) | |
415 | { | |
416 | tvalue = ns_t_cname; | |
417 | qtlen = 5; | |
418 | found_cname = TRUE; | |
419 | } | |
420 | else if (Ustrncmp(p, qtype, qtypelen) != 0 || !isspace(p[qtypelen])) continue; | |
421 | ||
422 | /* Found a relevant record */ | |
423 | ||
846430d9 JH |
424 | if (delay) |
425 | millisleep(delay); | |
426 | ||
4d4c2a9b JH |
427 | if (!rr_sec) |
428 | *dnssec = FALSE; /* cancel AD return */ | |
429 | ||
c55a77db PH |
430 | yield = 0; |
431 | *countptr = *countptr + 1; | |
432 | ||
433 | p += qtlen; | |
434 | while (isspace(*p)) p++; | |
435 | ||
75e0e026 PH |
436 | /* For a wildcard record, use the search name; otherwise use the record's |
437 | name in its original case because it might contain upper case letters. */ | |
438 | ||
439 | pk = packname((rrdomain[0] == '*')? domain : RRdomain, pk); | |
c55a77db PH |
440 | *pk++ = (tvalue >> 8) & 255; |
441 | *pk++ = (tvalue) & 255; | |
442 | *pk++ = 0; | |
443 | *pk++ = 1; /* class = IN */ | |
444 | ||
445 | pk += 4; /* TTL field; don't care */ | |
446 | ||
447 | rdlptr = pk; /* remember rdlength field */ | |
448 | pk += 2; | |
449 | ||
450 | /* The rest of the data depends on the type */ | |
451 | ||
452 | switch (tvalue) | |
453 | { | |
d2a2c69b JH |
454 | case ns_t_soa: |
455 | p = strtok(p, " "); | |
456 | ep = p + strlen(p); | |
457 | if (ep[-1] != '.') sprintf(CS ep, "%s.", zone); | |
458 | pk = packname(p, pk); /* primary ns */ | |
459 | p = strtok(NULL, " "); | |
460 | pk = packname(p , pk); /* responsible mailbox */ | |
461 | *(p += strlen(p)) = ' '; | |
462 | while (isspace(*p)) p++; | |
463 | pk = longfield(&p, pk); /* serial */ | |
464 | pk = longfield(&p, pk); /* refresh */ | |
465 | pk = longfield(&p, pk); /* retry */ | |
466 | pk = longfield(&p, pk); /* expire */ | |
467 | pk = longfield(&p, pk); /* minimum */ | |
468 | break; | |
c55a77db PH |
469 | |
470 | case ns_t_a: | |
d2a2c69b JH |
471 | for (i = 0; i < 4; i++) |
472 | { | |
473 | value = 0; | |
474 | while (isdigit(*p)) value = value*10 + *p++ - '0'; | |
475 | *pk++ = value; | |
476 | p++; | |
477 | } | |
478 | break; | |
c55a77db PH |
479 | |
480 | /* The only occurrence of a double colon is for ::1 */ | |
481 | case ns_t_aaaa: | |
d2a2c69b JH |
482 | if (Ustrcmp(p, "::1") == 0) |
483 | { | |
484 | memset(pk, 0, 15); | |
485 | pk += 15; | |
486 | *pk++ = 1; | |
487 | } | |
488 | else for (i = 0; i < 8; i++) | |
489 | { | |
490 | value = 0; | |
491 | while (isxdigit(*p)) | |
492 | { | |
493 | value = value * 16 + toupper(*p) - (isdigit(*p)? '0' : '7'); | |
494 | p++; | |
495 | } | |
496 | *pk++ = (value >> 8) & 255; | |
497 | *pk++ = value & 255; | |
498 | p++; | |
499 | } | |
500 | break; | |
c55a77db PH |
501 | |
502 | case ns_t_mx: | |
d2a2c69b JH |
503 | pk = shortfield(&p, pk); |
504 | if (ep[-1] != '.') sprintf(CS ep, "%s.", zone); | |
505 | pk = packname(p, pk); | |
506 | break; | |
c55a77db PH |
507 | |
508 | case ns_t_txt: | |
d2a2c69b JH |
509 | pp = pk++; |
510 | if (*p == '"') p++; /* Should always be the case */ | |
511 | while (*p != 0 && *p != '"') *pk++ = *p++; | |
512 | *pp = pk - pp - 1; | |
513 | break; | |
c55a77db | 514 | |
b4161d10 | 515 | case ns_t_tlsa: |
d2a2c69b JH |
516 | pk = bytefield(&p, pk); /* usage */ |
517 | pk = bytefield(&p, pk); /* selector */ | |
518 | pk = bytefield(&p, pk); /* match type */ | |
519 | while (isxdigit(*p)) | |
b4161d10 JH |
520 | { |
521 | value = toupper(*p) - (isdigit(*p) ? '0' : '7') << 4; | |
522 | if (isxdigit(*++p)) | |
523 | { | |
524 | value |= toupper(*p) - (isdigit(*p) ? '0' : '7'); | |
525 | p++; | |
526 | } | |
527 | *pk++ = value & 255; | |
528 | } | |
529 | ||
d2a2c69b | 530 | break; |
b4161d10 | 531 | |
c55a77db | 532 | case ns_t_srv: |
d2a2c69b JH |
533 | for (i = 0; i < 3; i++) |
534 | { | |
535 | value = 0; | |
536 | while (isdigit(*p)) value = value*10 + *p++ - '0'; | |
537 | while (isspace(*p)) p++; | |
538 | *pk++ = (value >> 8) & 255; | |
539 | *pk++ = value & 255; | |
540 | } | |
c55a77db PH |
541 | |
542 | /* Fall through */ | |
543 | ||
544 | case ns_t_cname: | |
545 | case ns_t_ns: | |
546 | case ns_t_ptr: | |
d2a2c69b JH |
547 | if (ep[-1] != '.') sprintf(CS ep, "%s.", zone); |
548 | pk = packname(p, pk); | |
549 | break; | |
c55a77db PH |
550 | } |
551 | ||
552 | /* Fill in the length, and we are done with this RR */ | |
553 | ||
554 | rdlptr[0] = ((pk - rdlptr - 2) >> 8) & 255; | |
555 | rdlptr[1] = (pk -rdlptr - 2) & 255; | |
c55a77db PH |
556 | } |
557 | ||
558 | *pkptr = pk; | |
559 | return (yield == HOST_NOT_FOUND && pass_on_not_found)? PASS_ON : yield; | |
560 | } | |
561 | ||
562 | ||
846430d9 JH |
563 | static void |
564 | alarmfn(int sig) | |
565 | { | |
566 | } | |
c55a77db PH |
567 | |
568 | /************************************************* | |
569 | * Entry point and main program * | |
570 | *************************************************/ | |
571 | ||
572 | int | |
573 | main(int argc, char **argv) | |
574 | { | |
575 | FILE *f; | |
576 | DIR *d; | |
75e0e026 | 577 | int domlen, qtypelen; |
c55a77db PH |
578 | int yield, count; |
579 | int i; | |
580 | int zonecount = 0; | |
c55a77db | 581 | struct dirent *de; |
c55a77db PH |
582 | zoneitem zones[32]; |
583 | uschar *qualify = NULL; | |
584 | uschar *p, *zone; | |
585 | uschar *zonefile = NULL; | |
586 | uschar domain[256]; | |
587 | uschar buffer[256]; | |
588 | uschar qtype[12]; | |
1fb7660f | 589 | uschar packet[2048 * 32 + 32]; |
c55a77db | 590 | uschar *pk = packet; |
4d4c2a9b | 591 | BOOL dnssec; |
c55a77db | 592 | |
846430d9 JH |
593 | signal(SIGALRM, alarmfn); |
594 | ||
c55a77db PH |
595 | if (argc != 4) |
596 | { | |
597 | fprintf(stderr, "fakens: expected 3 arguments, received %d\n", argc-1); | |
598 | return NO_RECOVERY; | |
599 | } | |
600 | ||
601 | /* Find the zones */ | |
602 | ||
5f3d0983 | 603 | (void)sprintf(CS buffer, "%s/dnszones", argv[1]); |
c55a77db PH |
604 | |
605 | d = opendir(CCS buffer); | |
606 | if (d == NULL) | |
607 | { | |
608 | fprintf(stderr, "fakens: failed to opendir %s: %s\n", buffer, | |
609 | strerror(errno)); | |
610 | return NO_RECOVERY; | |
611 | } | |
612 | ||
613 | while ((de = readdir(d)) != NULL) | |
614 | { | |
e265af1f | 615 | uschar *name = US de->d_name; |
c55a77db PH |
616 | if (Ustrncmp(name, "qualify.", 8) == 0) |
617 | { | |
e265af1f | 618 | qualify = fcopystring(US "%s", name + 7); |
c55a77db PH |
619 | continue; |
620 | } | |
621 | if (Ustrncmp(name, "db.", 3) != 0) continue; | |
622 | if (Ustrncmp(name + 3, "ip4.", 4) == 0) | |
e265af1f | 623 | zones[zonecount].zone = fcopystring(US "%s.in-addr.arpa", name + 6); |
c55a77db | 624 | else if (Ustrncmp(name + 3, "ip6.", 4) == 0) |
e265af1f | 625 | zones[zonecount].zone = fcopystring(US "%s.ip6.arpa", name + 6); |
c55a77db | 626 | else |
e265af1f JH |
627 | zones[zonecount].zone = fcopystring(US "%s", name + 2); |
628 | zones[zonecount++].zonefile = fcopystring(US "%s", name); | |
c55a77db PH |
629 | } |
630 | (void)closedir(d); | |
631 | ||
632 | /* Get the RR type and upper case it, and check that we recognize it. */ | |
633 | ||
634 | Ustrncpy(qtype, argv[3], sizeof(qtype)); | |
635 | qtypelen = Ustrlen(qtype); | |
636 | for (p = qtype; *p != 0; p++) *p = toupper(*p); | |
637 | ||
1fb7660f JH |
638 | /* Find the domain, lower case it, deal with any specials, |
639 | check that it is in a zone that we handle, | |
c55a77db PH |
640 | and set up the zone file name. The zone names in the table all start with a |
641 | dot. */ | |
642 | ||
643 | domlen = Ustrlen(argv[2]); | |
644 | if (argv[2][domlen-1] == '.') domlen--; | |
645 | Ustrncpy(domain, argv[2], domlen); | |
646 | domain[domlen] = 0; | |
647 | for (i = 0; i < domlen; i++) domain[i] = tolower(domain[i]); | |
648 | ||
1fb7660f JH |
649 | if (Ustrcmp(domain, "manyhome.test.ex") == 0 && Ustrcmp(qtype, "A") == 0) |
650 | { | |
651 | uschar *pk = packet + 12; | |
652 | uschar *rdlptr; | |
653 | int i, j; | |
654 | ||
655 | memset(packet, 0, 12); | |
656 | ||
657 | for (i = 104; i <= 111; i++) for (j = 0; j <= 255; j++) | |
658 | { | |
659 | pk = packname(domain, pk); | |
660 | *pk++ = (ns_t_a >> 8) & 255; | |
661 | *pk++ = (ns_t_a) & 255; | |
662 | *pk++ = 0; | |
663 | *pk++ = 1; /* class = IN */ | |
664 | pk += 4; /* TTL field; don't care */ | |
665 | rdlptr = pk; /* remember rdlength field */ | |
666 | pk += 2; | |
667 | ||
668 | *pk++ = 10; *pk++ = 250; *pk++ = i; *pk++ = j; | |
669 | ||
670 | rdlptr[0] = ((pk - rdlptr - 2) >> 8) & 255; | |
671 | rdlptr[1] = (pk - rdlptr - 2) & 255; | |
672 | } | |
673 | ||
674 | packet[6] = (2048 >> 8) & 255; | |
675 | packet[7] = 2048 & 255; | |
676 | packet[10] = 0; | |
677 | packet[11] = 0; | |
678 | ||
679 | (void)fwrite(packet, 1, pk - packet, stdout); | |
680 | return 0; | |
681 | } | |
682 | ||
683 | ||
c55a77db PH |
684 | if (Ustrchr(domain, '.') == NULL && qualify != NULL && |
685 | Ustrcmp(domain, "dontqualify") != 0) | |
686 | { | |
687 | Ustrcat(domain, qualify); | |
688 | domlen += Ustrlen(qualify); | |
689 | } | |
690 | ||
691 | for (i = 0; i < zonecount; i++) | |
692 | { | |
693 | int zlen; | |
694 | zone = zones[i].zone; | |
695 | zlen = Ustrlen(zone); | |
696 | if (Ustrcmp(domain, zone+1) == 0 || (domlen >= zlen && | |
697 | Ustrcmp(domain + domlen - zlen, zone) == 0)) | |
698 | { | |
699 | zonefile = zones[i].zonefile; | |
700 | break; | |
701 | } | |
702 | } | |
703 | ||
704 | if (zonefile == NULL) | |
705 | { | |
706 | fprintf(stderr, "fakens: query not in faked zone: domain is: %s\n", domain); | |
707 | return PASS_ON; | |
708 | } | |
709 | ||
5f3d0983 | 710 | (void)sprintf(CS buffer, "%s/dnszones/%s", argv[1], zonefile); |
c55a77db PH |
711 | |
712 | /* Initialize the start of the response packet. We don't have to fake up | |
713 | everything, because we know that Exim will look only at the answer and | |
714 | additional section parts. */ | |
715 | ||
716 | memset(packet, 0, 12); | |
717 | pk += 12; | |
718 | ||
719 | /* Open the zone file. */ | |
720 | ||
42ec9880 | 721 | f = fopen(CS buffer, "r"); |
c55a77db PH |
722 | if (f == NULL) |
723 | { | |
724 | fprintf(stderr, "fakens: failed to open %s: %s\n", buffer, strerror(errno)); | |
725 | return NO_RECOVERY; | |
726 | } | |
727 | ||
728 | /* Find the records we want, and add them to the result. */ | |
729 | ||
730 | count = 0; | |
4d4c2a9b | 731 | yield = find_records(f, zone, domain, qtype, qtypelen, &pk, &count, &dnssec); |
c55a77db PH |
732 | if (yield == NO_RECOVERY) goto END_OFF; |
733 | ||
734 | packet[6] = (count >> 8) & 255; | |
735 | packet[7] = count & 255; | |
736 | ||
75e0e026 PH |
737 | /* There is no need to return any additional records because Exim no longer |
738 | (from release 4.61) makes any use of them. */ | |
c55a77db | 739 | |
75e0e026 PH |
740 | packet[10] = 0; |
741 | packet[11] = 0; | |
c55a77db | 742 | |
4d4c2a9b JH |
743 | if (dnssec) |
744 | ((HEADER *)packet)->ad = 1; | |
745 | ||
c55a77db PH |
746 | /* Close the zone file, write the result, and return. */ |
747 | ||
748 | END_OFF: | |
749 | (void)fclose(f); | |
750 | (void)fwrite(packet, 1, pk - packet, stdout); | |
751 | return yield; | |
752 | } | |
753 | ||
4d4c2a9b JH |
754 | /* vi: aw ai sw=2 |
755 | */ | |
c55a77db | 756 | /* End of fakens.c */ |