790cfd2b |
1 | /* |
2 | * adnsresfilter.c |
3 | * - filter which does resolving, not part of the library |
4 | */ |
5 | /* |
6 | * This file is |
cc0f95d0 |
7 | * Copyright (C) 1999-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
790cfd2b |
8 | * |
9 | * It is part of adns, which is |
89435c42 |
10 | * Copyright (C) 1997-2000 Ian Jackson <ian@davenant.greenend.org.uk> |
c6826df6 |
11 | * Copyright (C) 1999-2000 Tony Finch <dot@dotat.at> |
790cfd2b |
12 | * |
13 | * This program is free software; you can redistribute it and/or modify |
14 | * it under the terms of the GNU General Public License as published by |
15 | * the Free Software Foundation; either version 2, or (at your option) |
16 | * any later version. |
17 | * |
18 | * This program is distributed in the hope that it will be useful, |
19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
21 | * GNU General Public License for more details. |
22 | * |
23 | * You should have received a copy of the GNU General Public License |
24 | * along with this program; if not, write to the Free Software Foundation, |
25 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
26 | */ |
27 | |
28 | #include <stdio.h> |
29 | #include <stdlib.h> |
30 | #include <string.h> |
31 | #include <errno.h> |
32 | #include <search.h> |
33 | #include <assert.h> |
34 | #include <ctype.h> |
35 | |
93b54ac1 |
36 | #include <sys/types.h> |
37 | #include <unistd.h> |
8a4e090e |
38 | #include <fcntl.h> |
83e1be2f |
39 | |
790cfd2b |
40 | #include "config.h" |
cc0f95d0 |
41 | #include "adns.h" |
83e1be2f |
42 | #include "dlist.h" |
43 | #include "tvarith.h" |
8a5e5147 |
44 | #include "client.h" |
83e1be2f |
45 | |
ae0da6f3 |
46 | #ifdef ADNS_REGRESS_TEST |
47 | # include "hredirect.h" |
48 | #endif |
49 | |
83e1be2f |
50 | struct outqueuenode { |
51 | struct outqueuenode *next, *back; |
52 | void *buffer; |
53 | char *textp; |
54 | int textlen; |
55 | struct timeval printbefore; |
56 | struct treething *addr; |
57 | }; |
58 | |
a93e4dbf |
59 | static int bracket, forever, address; |
9463e0a6 |
60 | static unsigned long timeout= 1000; |
83e1be2f |
61 | static adns_rrtype rrt= adns_r_ptr; |
ae0da6f3 |
62 | static adns_initflags initflags= 0; |
63 | static const char *config_text; |
83e1be2f |
64 | |
65 | static int outblocked, inputeof; |
66 | static struct { struct outqueuenode *head, *tail; } outqueue; |
67 | static int peroutqueuenode, outqueuelen; |
68 | |
69 | static struct sockaddr_in sa; |
70 | static adns_state ads; |
71 | |
72 | static char addrtextbuf[14]; |
73 | static int cbyte, inbyte, inbuf; |
74 | static unsigned char bytes[4]; |
75 | static struct timeval printbefore; |
76 | |
77 | struct treething { |
78 | unsigned char bytes[4]; |
79 | adns_query qu; |
80 | adns_answer *ans; |
81 | }; |
82 | |
83 | static struct treething *newthing; |
84 | static void *treeroot; |
85 | |
86 | static int nonblock(int fd, int isnonblock) { |
87 | int r; |
88 | |
89 | r= fcntl(fd,F_GETFL); |
90 | if (r==-1) return -1; |
91 | r= fcntl(fd,F_SETFL, isnonblock ? r|O_NONBLOCK : r&~O_NONBLOCK); |
92 | if (r==-1) return -1; |
93 | return 0; |
94 | } |
95 | |
8a5e5147 |
96 | void quitnow(int exitstatus) { |
83e1be2f |
97 | nonblock(0,0); |
98 | nonblock(1,0); |
99 | exit(exitstatus); |
100 | } |
790cfd2b |
101 | |
102 | static void sysfail(const char *what) NONRETURNING; |
103 | static void sysfail(const char *what) { |
104 | fprintf(stderr,"adnsresfilter: system call failed: %s: %s\n",what,strerror(errno)); |
8a5e5147 |
105 | quitnow(2); |
83e1be2f |
106 | } |
107 | |
108 | static void *xmalloc(size_t sz) { |
109 | void *r; |
110 | r= malloc(sz); if (r) return r; |
111 | sysfail("malloc"); |
790cfd2b |
112 | } |
113 | |
114 | static void outputerr(void) NONRETURNING; |
115 | static void outputerr(void) { sysfail("write to stdout"); } |
116 | |
117 | static void usage(void) { |
118 | if (printf("usage: adnsresfilter [<options ...>]\n" |
8a5e5147 |
119 | " adnsresfilter -h|--help | --version\n" |
3d89679a |
120 | "options: -t<milliseconds>|--timeout <milliseconds>\n" |
121 | " -w|--wait (always wait for queries to time out or fail)\n" |
122 | " -b|--brackets (require [...] around IP addresses)\n" |
123 | " -a|--address (always include [address] in output)\n" |
124 | " -u|--unchecked (do not forward map for checking)\n" |
ae0da6f3 |
125 | " --config <text> (use this instead of resolv.conf)\n" |
126 | " --debug (turn on adns resolver debugging)\n" |
3d89679a |
127 | "Timeout is the maximum amount to delay any particular bit of output for.\n" |
ae0da6f3 |
128 | "Lookups will go on in the background. Default timeout = 1000 (ms).\n") |
790cfd2b |
129 | == EOF) outputerr(); |
d024926c |
130 | if (fflush(stdout)) sysfail("flush stdout"); |
790cfd2b |
131 | } |
132 | |
133 | static void usageerr(const char *why) NONRETURNING; |
134 | static void usageerr(const char *why) { |
135 | fprintf(stderr,"adnsresfilter: bad usage: %s\n",why); |
136 | usage(); |
8a5e5147 |
137 | quitnow(1); |
790cfd2b |
138 | } |
139 | |
140 | static void adnsfail(const char *what, int e) NONRETURNING; |
141 | static void adnsfail(const char *what, int e) { |
142 | fprintf(stderr,"adnsresfilter: adns call failed: %s: %s\n",what,strerror(e)); |
8a5e5147 |
143 | quitnow(2); |
790cfd2b |
144 | } |
145 | |
7ba81901 |
146 | static void settimeout(const char *arg) { |
147 | char *ep; |
148 | timeout= strtoul(arg,&ep,0); |
149 | if (*ep) usageerr("invalid timeout"); |
790cfd2b |
150 | } |
151 | |
83e1be2f |
152 | static void parseargs(const char *const *argv) { |
790cfd2b |
153 | const char *arg; |
83e1be2f |
154 | int c; |
790cfd2b |
155 | |
156 | while ((arg= *++argv)) { |
157 | if (arg[0] != '-') usageerr("no non-option arguments are allowed"); |
158 | if (arg[1] == '-') { |
ae0da6f3 |
159 | if (!strcmp(arg,"--timeout")) { |
160 | if (!(arg= *++argv)) usageerr("--timeout needs a value"); |
161 | settimeout(arg); |
162 | forever= 0; |
790cfd2b |
163 | } else if (!strcmp(arg,"--wait")) { |
164 | forever= 1; |
ae0da6f3 |
165 | } else if (!strcmp(arg,"--brackets")) { |
166 | bracket= 1; |
a93e4dbf |
167 | } else if (!strcmp(arg,"--address")) { |
168 | address= 1; |
ae0da6f3 |
169 | } else if (!strcmp(arg,"--unchecked")) { |
170 | rrt= adns_r_ptr_raw; |
171 | } else if (!strcmp(arg,"--config")) { |
172 | if (!(arg= *++argv)) usageerr("--config needs a value"); |
173 | config_text= arg; |
174 | } else if (!strcmp(arg,"--debug")) { |
175 | initflags |= adns_if_debug; |
790cfd2b |
176 | } else if (!strcmp(arg,"--help")) { |
8a5e5147 |
177 | usage(); quitnow(0); |
178 | } else if (!strcmp(arg,"--version")) { |
179 | VERSION_PRINT_QUIT("adnsresfilter"); quitnow(0); |
790cfd2b |
180 | } else { |
181 | usageerr("unknown long option"); |
182 | } |
183 | } else { |
184 | while ((c= *++arg)) { |
185 | switch (c) { |
ae0da6f3 |
186 | case 't': |
187 | if (*++arg) settimeout(arg); |
188 | else if ((arg= *++argv)) settimeout(arg); |
189 | else usageerr("-t needs a value"); |
190 | forever= 0; |
191 | arg= "\0"; |
790cfd2b |
192 | break; |
193 | case 'w': |
194 | forever= 1; |
195 | break; |
ae0da6f3 |
196 | case 'b': |
197 | bracket= 1; |
198 | break; |
a93e4dbf |
199 | case 'a': |
200 | address= 1; |
201 | break; |
ae0da6f3 |
202 | case 'u': |
203 | rrt= adns_r_ptr_raw; |
204 | break; |
790cfd2b |
205 | case 'h': |
7ba81901 |
206 | usage(); |
8a5e5147 |
207 | quitnow(0); |
790cfd2b |
208 | default: |
209 | usageerr("unknown short option"); |
210 | } |
211 | } |
212 | } |
213 | } |
83e1be2f |
214 | } |
790cfd2b |
215 | |
83e1be2f |
216 | static void queueoutchar(int c) { |
217 | struct outqueuenode *entry; |
218 | |
219 | entry= outqueue.tail; |
7ba81901 |
220 | if (!entry || entry->addr || entry->textlen >= peroutqueuenode) { |
221 | peroutqueuenode= !peroutqueuenode || !entry || entry->addr ? 128 : |
222 | peroutqueuenode >= 1024 ? 4096 : peroutqueuenode<<2; |
83e1be2f |
223 | entry= xmalloc(sizeof(*entry)); |
83e1be2f |
224 | entry->buffer= xmalloc(peroutqueuenode); |
225 | entry->textp= entry->buffer; |
226 | entry->textlen= 0; |
227 | entry->addr= 0; |
228 | LIST_LINK_TAIL(outqueue,entry); |
229 | outqueuelen++; |
230 | } |
7ba81901 |
231 | entry->textp[entry->textlen++]= c; |
83e1be2f |
232 | } |
790cfd2b |
233 | |
83e1be2f |
234 | static void queueoutstr(const char *str, int len) { |
7ba81901 |
235 | while (len-- > 0) queueoutchar(*str++); |
83e1be2f |
236 | } |
790cfd2b |
237 | |
83e1be2f |
238 | static void writestdout(struct outqueuenode *entry) { |
239 | int r; |
240 | |
241 | while (entry->textlen) { |
242 | r= write(1, entry->textp, entry->textlen); |
243 | if (r < 0) { |
244 | if (errno == EINTR) continue; |
245 | if (errno == EAGAIN) { outblocked= 1; break; } |
246 | sysfail("write stdout"); |
247 | } |
7ba81901 |
248 | assert(r <= entry->textlen); |
83e1be2f |
249 | entry->textp += r; |
250 | entry->textlen -= r; |
251 | } |
252 | if (!entry->textlen) { |
253 | LIST_UNLINK(outqueue,entry); |
254 | free(entry->buffer); |
255 | free(entry); |
256 | outqueuelen--; |
257 | } |
258 | } |
259 | |
260 | static void replacetextwithname(struct outqueuenode *entry) { |
a93e4dbf |
261 | char *name, *newbuf; |
262 | int namelen, newlen; |
263 | |
264 | name= entry->addr->ans->rrs.str[0]; |
265 | namelen= strlen(name); |
266 | if (!address) { |
267 | free(entry->buffer); |
268 | entry->buffer= 0; |
269 | entry->textp= name; |
270 | entry->textlen= namelen; |
271 | } else { |
272 | newlen= entry->textlen + namelen + (bracket ? 0 : 2); |
273 | newbuf= xmalloc(newlen + 1); |
274 | sprintf(newbuf, bracket ? "%s%.*s" : "%s[%.*s]", name, entry->textlen, entry->textp); |
275 | free(entry->buffer); |
276 | entry->buffer= entry->textp= newbuf; |
277 | entry->textlen= newlen; |
278 | } |
83e1be2f |
279 | } |
280 | |
281 | static void checkadnsqueries(void) { |
282 | adns_query qu; |
283 | adns_answer *ans; |
284 | void *context; |
285 | struct treething *foundthing; |
286 | int r; |
287 | |
288 | for (;;) { |
289 | qu= 0; context= 0; ans= 0; |
290 | r= adns_check(ads,&qu,&ans,&context); |
291 | if (r == ESRCH || r == EAGAIN) break; |
292 | assert(!r); |
293 | foundthing= context; |
294 | foundthing->ans= ans; |
295 | foundthing->qu= 0; |
296 | } |
297 | } |
298 | |
299 | static void restartbuf(void) { |
300 | if (inbuf>0) queueoutstr(addrtextbuf,inbuf); |
790cfd2b |
301 | inbuf= 0; |
83e1be2f |
302 | } |
303 | |
7ba81901 |
304 | static int comparer(const void *a, const void *b) { |
305 | return memcmp(a,b,4); |
306 | } |
307 | |
83e1be2f |
308 | static void procaddr(void) { |
309 | struct treething *foundthing; |
310 | void **searchfound; |
311 | struct outqueuenode *entry; |
312 | int r; |
313 | |
314 | if (!newthing) { |
315 | newthing= xmalloc(sizeof(struct treething)); |
316 | newthing->qu= 0; |
317 | newthing->ans= 0; |
318 | } |
319 | |
320 | memcpy(newthing->bytes,bytes,4); |
321 | searchfound= tsearch(newthing,&treeroot,comparer); |
322 | if (!searchfound) sysfail("tsearch"); |
323 | foundthing= *searchfound; |
324 | |
325 | if (foundthing == newthing) { |
7ba81901 |
326 | newthing= 0; |
83e1be2f |
327 | memcpy(&sa.sin_addr,bytes,4); |
328 | r= adns_submit_reverse(ads, (const struct sockaddr*)&sa, |
329 | rrt,0,foundthing,&foundthing->qu); |
330 | if (r) adnsfail("submit",r); |
331 | } |
332 | entry= xmalloc(sizeof(*entry)); |
333 | entry->buffer= xmalloc(inbuf); |
334 | entry->textp= entry->buffer; |
335 | memcpy(entry->textp,addrtextbuf,inbuf); |
336 | entry->textlen= inbuf; |
337 | entry->addr= foundthing; |
7ba81901 |
338 | entry->printbefore= printbefore; |
83e1be2f |
339 | LIST_LINK_TAIL(outqueue,entry); |
340 | outqueuelen++; |
341 | inbuf= 0; |
342 | cbyte= -1; |
343 | } |
344 | |
345 | static void startaddr(void) { |
346 | bytes[cbyte=0]= 0; |
347 | inbyte= 0; |
348 | } |
349 | |
350 | static void readstdin(void) { |
351 | char readbuf[512], *p; |
352 | int r, c, nbyte; |
353 | |
354 | while ((r= read(0,readbuf,sizeof(readbuf))) <= 0) { |
355 | if (r == 0) { inputeof= 1; return; } |
356 | if (r == EAGAIN) return; |
357 | if (r != EINTR) sysfail("read stdin"); |
358 | } |
359 | for (p=readbuf; r>0; r--,p++) { |
7ba81901 |
360 | c= *p; |
790cfd2b |
361 | if (cbyte==-1 && bracket && c=='[') { |
83e1be2f |
362 | addrtextbuf[inbuf++]= c; |
790cfd2b |
363 | startaddr(); |
364 | } else if (cbyte==-1 && !bracket && !isalnum(c)) { |
83e1be2f |
365 | queueoutchar(c); |
790cfd2b |
366 | startaddr(); |
367 | } else if (cbyte>=0 && inbyte<3 && c>='0' && c<='9' && |
368 | (nbyte= bytes[cbyte]*10 + (c-'0')) <= 255) { |
369 | bytes[cbyte]= nbyte; |
83e1be2f |
370 | addrtextbuf[inbuf++]= c; |
790cfd2b |
371 | inbyte++; |
372 | } else if (cbyte>=0 && cbyte<3 && inbyte>0 && c=='.') { |
373 | bytes[++cbyte]= 0; |
83e1be2f |
374 | addrtextbuf[inbuf++]= c; |
790cfd2b |
375 | inbyte= 0; |
376 | } else if (cbyte==3 && inbyte>0 && bracket && c==']') { |
83e1be2f |
377 | addrtextbuf[inbuf++]= c; |
790cfd2b |
378 | procaddr(); |
379 | } else if (cbyte==3 && inbyte>0 && !bracket && !isalnum(c)) { |
380 | procaddr(); |
83e1be2f |
381 | queueoutchar(c); |
790cfd2b |
382 | startaddr(); |
383 | } else { |
384 | restartbuf(); |
83e1be2f |
385 | queueoutchar(c); |
790cfd2b |
386 | cbyte= -1; |
387 | if (!bracket && !isalnum(c)) startaddr(); |
388 | } |
389 | } |
83e1be2f |
390 | } |
391 | |
392 | static void startup(void) { |
393 | int r; |
394 | |
83e1be2f |
395 | if (nonblock(0,1)) sysfail("set stdin to nonblocking mode"); |
396 | if (nonblock(1,1)) sysfail("set stdout to nonblocking mode"); |
397 | memset(&sa,0,sizeof(sa)); |
398 | sa.sin_family= AF_INET; |
ae0da6f3 |
399 | if (config_text) { |
400 | r= adns_init_strcfg(&ads,initflags,stderr,config_text); |
401 | } else { |
402 | r= adns_init(&ads,initflags,0); |
403 | } |
404 | if (r) adnsfail("init",r); |
83e1be2f |
405 | cbyte= -1; |
406 | inbyte= -1; |
407 | inbuf= 0; |
408 | if (!bracket) startaddr(); |
409 | } |
410 | |
411 | int main(int argc, const char *const *argv) { |
412 | int r, maxfd; |
413 | fd_set readfds, writefds, exceptfds; |
414 | struct outqueuenode *entry; |
415 | struct timeval *tv, tvbuf, now; |
416 | |
417 | parseargs(argv); |
418 | startup(); |
419 | |
420 | while (!inputeof || outqueue.head) { |
421 | maxfd= 2; |
422 | tv= 0; |
423 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
424 | if ((entry= outqueue.head) && !outblocked) { |
425 | if (!entry->addr) { |
426 | writestdout(entry); |
427 | continue; |
7ba81901 |
428 | } |
429 | if (entry->addr->ans) { |
83e1be2f |
430 | if (entry->addr->ans->nrrs) |
431 | replacetextwithname(entry); |
432 | entry->addr= 0; |
433 | continue; |
434 | } |
435 | r= gettimeofday(&now,0); if (r) sysfail("gettimeofday"); |
436 | if (forever) { |
437 | tv= 0; |
438 | } else if (!timercmp(&now,&entry->printbefore,<)) { |
439 | entry->addr= 0; |
440 | continue; |
441 | } else { |
7ba81901 |
442 | tvbuf.tv_sec= entry->printbefore.tv_sec - now.tv_sec - 1; |
443 | tvbuf.tv_usec= entry->printbefore.tv_usec - now.tv_usec + 1000000; |
83e1be2f |
444 | tvbuf.tv_sec += tvbuf.tv_usec / 1000000; |
445 | tvbuf.tv_usec %= 1000000; |
446 | tv= &tvbuf; |
447 | } |
448 | adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds, |
449 | &tv,&tvbuf,&now); |
450 | } |
451 | if (outblocked) FD_SET(1,&writefds); |
7ba81901 |
452 | if (!inputeof && outqueuelen<1024) FD_SET(0,&readfds); |
83e1be2f |
453 | |
454 | r= select(maxfd,&readfds,&writefds,&exceptfds,tv); |
455 | if (r < 0) { if (r == EINTR) continue; else sysfail("select"); } |
456 | |
457 | r= gettimeofday(&now,0); if (r) sysfail("gettimeofday"); |
458 | adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,&now); |
459 | checkadnsqueries(); |
460 | |
461 | if (FD_ISSET(0,&readfds)) { |
462 | if (!forever) { |
463 | printbefore= now; |
464 | timevaladd(&printbefore,timeout); |
465 | } |
466 | readstdin(); |
467 | } else if (FD_ISSET(1,&writefds)) { |
468 | outblocked= 0; |
469 | } |
470 | } |
83e1be2f |
471 | if (nonblock(0,0)) sysfail("un-nonblock stdin"); |
472 | if (nonblock(1,0)) sysfail("un-nonblock stdout"); |
d024926c |
473 | adns_finish(ads); |
790cfd2b |
474 | exit(0); |
475 | } |