592aa664 |
1 | /* |
2 | * adnsresfilter.c |
3 | * - filter which does resolving, not part of the library |
4 | */ |
5 | /* |
6 | * This file is |
7 | * Copyright (C) 1999 Ian Jackson <ian@davenant.greenend.org.uk> |
8 | * |
9 | * It is part of adns, which is |
10 | * Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk> |
11 | * Copyright (C) 1999 Tony Finch <dot@dotat.at> |
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 | |
2953d358 |
36 | #include <sys/fcntl.h> |
37 | |
592aa664 |
38 | #include "adns.h" |
39 | #include "config.h" |
2953d358 |
40 | #include "dlist.h" |
41 | #include "tvarith.h" |
42 | |
43 | struct outqueuenode { |
44 | struct outqueuenode *next, *back; |
45 | void *buffer; |
46 | char *textp; |
47 | int textlen; |
48 | struct timeval printbefore; |
49 | struct treething *addr; |
50 | }; |
51 | |
41559f53 |
52 | static int bracket, forever; |
53 | static unsigned long timeout=100; |
2953d358 |
54 | static adns_rrtype rrt= adns_r_ptr; |
55 | |
56 | static int outblocked, inputeof; |
57 | static struct { struct outqueuenode *head, *tail; } outqueue; |
58 | static int peroutqueuenode, outqueuelen; |
59 | |
60 | static struct sockaddr_in sa; |
61 | static adns_state ads; |
62 | |
63 | static char addrtextbuf[14]; |
64 | static int cbyte, inbyte, inbuf; |
65 | static unsigned char bytes[4]; |
66 | static struct timeval printbefore; |
67 | |
68 | struct treething { |
69 | unsigned char bytes[4]; |
70 | adns_query qu; |
71 | adns_answer *ans; |
72 | }; |
73 | |
74 | static struct treething *newthing; |
75 | static void *treeroot; |
76 | |
77 | static int nonblock(int fd, int isnonblock) { |
78 | int r; |
79 | |
80 | r= fcntl(fd,F_GETFL); |
81 | if (r==-1) return -1; |
82 | r= fcntl(fd,F_SETFL, isnonblock ? r|O_NONBLOCK : r&~O_NONBLOCK); |
83 | if (r==-1) return -1; |
84 | return 0; |
85 | } |
86 | |
87 | static void quit(int exitstatus) NONRETURNING; |
88 | static void quit(int exitstatus) { |
89 | nonblock(0,0); |
90 | nonblock(1,0); |
91 | exit(exitstatus); |
92 | } |
592aa664 |
93 | |
94 | static void sysfail(const char *what) NONRETURNING; |
95 | static void sysfail(const char *what) { |
96 | fprintf(stderr,"adnsresfilter: system call failed: %s: %s\n",what,strerror(errno)); |
2953d358 |
97 | quit(2); |
98 | } |
99 | |
100 | static void *xmalloc(size_t sz) { |
101 | void *r; |
102 | r= malloc(sz); if (r) return r; |
103 | sysfail("malloc"); |
592aa664 |
104 | } |
105 | |
106 | static void outputerr(void) NONRETURNING; |
107 | static void outputerr(void) { sysfail("write to stdout"); } |
108 | |
109 | static void usage(void) { |
110 | if (printf("usage: adnsresfilter [<options ...>]\n" |
111 | " adnsresfilter -h|--help\n" |
112 | "options: -b|--brackets\n" |
113 | " -w|--wait\n" |
41559f53 |
114 | " -t<timeout>|--timeout <milliseconds>\n" |
592aa664 |
115 | " -u|--unchecked\n") |
116 | == EOF) outputerr(); |
117 | } |
118 | |
119 | static void usageerr(const char *why) NONRETURNING; |
120 | static void usageerr(const char *why) { |
121 | fprintf(stderr,"adnsresfilter: bad usage: %s\n",why); |
122 | usage(); |
2953d358 |
123 | quit(1); |
592aa664 |
124 | } |
125 | |
126 | static void adnsfail(const char *what, int e) NONRETURNING; |
127 | static void adnsfail(const char *what, int e) { |
128 | fprintf(stderr,"adnsresfilter: adns call failed: %s: %s\n",what,strerror(e)); |
2953d358 |
129 | quit(2); |
592aa664 |
130 | } |
131 | |
41559f53 |
132 | static void settimeout(const char *arg) { |
133 | char *ep; |
134 | timeout= strtoul(arg,&ep,0); |
135 | if (*ep) usageerr("invalid timeout"); |
592aa664 |
136 | } |
137 | |
2953d358 |
138 | static void parseargs(const char *const *argv) { |
592aa664 |
139 | const char *arg; |
2953d358 |
140 | int c; |
592aa664 |
141 | |
142 | while ((arg= *++argv)) { |
143 | if (arg[0] != '-') usageerr("no non-option arguments are allowed"); |
144 | if (arg[1] == '-') { |
145 | if (!strcmp(arg,"--brackets")) { |
146 | bracket= 1; |
147 | } else if (!strcmp(arg,"--unchecked")) { |
148 | rrt= adns_r_ptr_raw; |
149 | } else if (!strcmp(arg,"--wait")) { |
150 | forever= 1; |
151 | } else if (!strcmp(arg,"--help")) { |
2953d358 |
152 | usage(); quit(0); |
41559f53 |
153 | } else if (!strcmp(arg,"--timeout")) { |
154 | if (!(arg= *++argv)) usageerr("--timeout needs a value"); |
155 | settimeout(arg); |
156 | forever= 0; |
592aa664 |
157 | } else { |
158 | usageerr("unknown long option"); |
159 | } |
160 | } else { |
161 | while ((c= *++arg)) { |
162 | switch (c) { |
163 | case 'b': |
164 | bracket= 1; |
165 | break; |
166 | case 'u': |
167 | rrt= adns_r_ptr_raw; |
168 | break; |
169 | case 'w': |
170 | forever= 1; |
171 | break; |
172 | case 'h': |
41559f53 |
173 | usage(); |
174 | quit(0); |
175 | case 't': |
176 | if (*++arg) settimeout(arg); |
177 | else if ((arg= *++argv)) settimeout(arg); |
178 | else usageerr("-t needs a value"); |
179 | forever= 0; |
180 | arg= "\0"; |
181 | break; |
592aa664 |
182 | default: |
183 | usageerr("unknown short option"); |
184 | } |
185 | } |
186 | } |
187 | } |
2953d358 |
188 | } |
592aa664 |
189 | |
2953d358 |
190 | static void queueoutchar(int c) { |
191 | struct outqueuenode *entry; |
192 | |
193 | entry= outqueue.tail; |
41559f53 |
194 | if (!entry || entry->addr || entry->textlen >= peroutqueuenode) { |
195 | peroutqueuenode= !peroutqueuenode || !entry || entry->addr ? 128 : |
196 | peroutqueuenode >= 1024 ? 4096 : peroutqueuenode<<2; |
2953d358 |
197 | entry= xmalloc(sizeof(*entry)); |
2953d358 |
198 | entry->buffer= xmalloc(peroutqueuenode); |
199 | entry->textp= entry->buffer; |
200 | entry->textlen= 0; |
201 | entry->addr= 0; |
202 | LIST_LINK_TAIL(outqueue,entry); |
203 | outqueuelen++; |
204 | } |
41559f53 |
205 | entry->textp[entry->textlen++]= c; |
2953d358 |
206 | } |
592aa664 |
207 | |
2953d358 |
208 | static void queueoutstr(const char *str, int len) { |
41559f53 |
209 | while (len-- > 0) queueoutchar(*str++); |
2953d358 |
210 | } |
592aa664 |
211 | |
2953d358 |
212 | static void writestdout(struct outqueuenode *entry) { |
213 | int r; |
214 | |
215 | while (entry->textlen) { |
216 | r= write(1, entry->textp, entry->textlen); |
217 | if (r < 0) { |
218 | if (errno == EINTR) continue; |
219 | if (errno == EAGAIN) { outblocked= 1; break; } |
220 | sysfail("write stdout"); |
221 | } |
41559f53 |
222 | assert(r <= entry->textlen); |
2953d358 |
223 | entry->textp += r; |
224 | entry->textlen -= r; |
225 | } |
226 | if (!entry->textlen) { |
227 | LIST_UNLINK(outqueue,entry); |
228 | free(entry->buffer); |
229 | free(entry); |
230 | outqueuelen--; |
231 | } |
232 | } |
233 | |
234 | static void replacetextwithname(struct outqueuenode *entry) { |
235 | free(entry->buffer); |
236 | entry->buffer= 0; |
237 | entry->textp= entry->addr->ans->rrs.str[0]; |
238 | entry->textlen= strlen(entry->textp); |
239 | } |
240 | |
241 | static void checkadnsqueries(void) { |
242 | adns_query qu; |
243 | adns_answer *ans; |
244 | void *context; |
245 | struct treething *foundthing; |
246 | int r; |
247 | |
248 | for (;;) { |
249 | qu= 0; context= 0; ans= 0; |
250 | r= adns_check(ads,&qu,&ans,&context); |
251 | if (r == ESRCH || r == EAGAIN) break; |
252 | assert(!r); |
253 | foundthing= context; |
254 | foundthing->ans= ans; |
255 | foundthing->qu= 0; |
256 | } |
257 | } |
258 | |
259 | static void restartbuf(void) { |
260 | if (inbuf>0) queueoutstr(addrtextbuf,inbuf); |
592aa664 |
261 | inbuf= 0; |
2953d358 |
262 | } |
263 | |
41559f53 |
264 | static int comparer(const void *a, const void *b) { |
265 | return memcmp(a,b,4); |
266 | } |
267 | |
2953d358 |
268 | static void procaddr(void) { |
269 | struct treething *foundthing; |
270 | void **searchfound; |
271 | struct outqueuenode *entry; |
272 | int r; |
273 | |
274 | if (!newthing) { |
275 | newthing= xmalloc(sizeof(struct treething)); |
276 | newthing->qu= 0; |
277 | newthing->ans= 0; |
278 | } |
279 | |
280 | memcpy(newthing->bytes,bytes,4); |
281 | searchfound= tsearch(newthing,&treeroot,comparer); |
282 | if (!searchfound) sysfail("tsearch"); |
283 | foundthing= *searchfound; |
284 | |
285 | if (foundthing == newthing) { |
41559f53 |
286 | newthing= 0; |
2953d358 |
287 | memcpy(&sa.sin_addr,bytes,4); |
288 | r= adns_submit_reverse(ads, (const struct sockaddr*)&sa, |
289 | rrt,0,foundthing,&foundthing->qu); |
290 | if (r) adnsfail("submit",r); |
291 | } |
292 | entry= xmalloc(sizeof(*entry)); |
293 | entry->buffer= xmalloc(inbuf); |
294 | entry->textp= entry->buffer; |
295 | memcpy(entry->textp,addrtextbuf,inbuf); |
296 | entry->textlen= inbuf; |
297 | entry->addr= foundthing; |
41559f53 |
298 | entry->printbefore= printbefore; |
2953d358 |
299 | LIST_LINK_TAIL(outqueue,entry); |
300 | outqueuelen++; |
301 | inbuf= 0; |
302 | cbyte= -1; |
303 | } |
304 | |
305 | static void startaddr(void) { |
306 | bytes[cbyte=0]= 0; |
307 | inbyte= 0; |
308 | } |
309 | |
310 | static void readstdin(void) { |
311 | char readbuf[512], *p; |
312 | int r, c, nbyte; |
313 | |
314 | while ((r= read(0,readbuf,sizeof(readbuf))) <= 0) { |
315 | if (r == 0) { inputeof= 1; return; } |
316 | if (r == EAGAIN) return; |
317 | if (r != EINTR) sysfail("read stdin"); |
318 | } |
319 | for (p=readbuf; r>0; r--,p++) { |
41559f53 |
320 | c= *p; |
592aa664 |
321 | if (cbyte==-1 && bracket && c=='[') { |
2953d358 |
322 | addrtextbuf[inbuf++]= c; |
592aa664 |
323 | startaddr(); |
324 | } else if (cbyte==-1 && !bracket && !isalnum(c)) { |
2953d358 |
325 | queueoutchar(c); |
592aa664 |
326 | startaddr(); |
327 | } else if (cbyte>=0 && inbyte<3 && c>='0' && c<='9' && |
328 | (nbyte= bytes[cbyte]*10 + (c-'0')) <= 255) { |
329 | bytes[cbyte]= nbyte; |
2953d358 |
330 | addrtextbuf[inbuf++]= c; |
592aa664 |
331 | inbyte++; |
332 | } else if (cbyte>=0 && cbyte<3 && inbyte>0 && c=='.') { |
333 | bytes[++cbyte]= 0; |
2953d358 |
334 | addrtextbuf[inbuf++]= c; |
592aa664 |
335 | inbyte= 0; |
336 | } else if (cbyte==3 && inbyte>0 && bracket && c==']') { |
2953d358 |
337 | addrtextbuf[inbuf++]= c; |
592aa664 |
338 | procaddr(); |
339 | } else if (cbyte==3 && inbyte>0 && !bracket && !isalnum(c)) { |
340 | procaddr(); |
2953d358 |
341 | queueoutchar(c); |
592aa664 |
342 | startaddr(); |
343 | } else { |
344 | restartbuf(); |
2953d358 |
345 | queueoutchar(c); |
592aa664 |
346 | cbyte= -1; |
347 | if (!bracket && !isalnum(c)) startaddr(); |
348 | } |
349 | } |
592aa664 |
350 | if (cbyte==3 && inbyte>0 && !bracket) procaddr(); |
2953d358 |
351 | } |
352 | |
353 | static void startup(void) { |
354 | int r; |
355 | |
2953d358 |
356 | if (nonblock(0,1)) sysfail("set stdin to nonblocking mode"); |
357 | if (nonblock(1,1)) sysfail("set stdout to nonblocking mode"); |
358 | memset(&sa,0,sizeof(sa)); |
359 | sa.sin_family= AF_INET; |
360 | r= adns_init(&ads,0,0); if (r) adnsfail("init",r); |
361 | cbyte= -1; |
362 | inbyte= -1; |
363 | inbuf= 0; |
364 | if (!bracket) startaddr(); |
365 | } |
366 | |
367 | int main(int argc, const char *const *argv) { |
368 | int r, maxfd; |
369 | fd_set readfds, writefds, exceptfds; |
370 | struct outqueuenode *entry; |
371 | struct timeval *tv, tvbuf, now; |
372 | |
373 | parseargs(argv); |
374 | startup(); |
375 | |
376 | while (!inputeof || outqueue.head) { |
377 | maxfd= 2; |
378 | tv= 0; |
379 | FD_ZERO(&readfds); FD_ZERO(&writefds); FD_ZERO(&exceptfds); |
380 | if ((entry= outqueue.head) && !outblocked) { |
381 | if (!entry->addr) { |
382 | writestdout(entry); |
383 | continue; |
41559f53 |
384 | } |
385 | if (entry->addr->ans) { |
2953d358 |
386 | if (entry->addr->ans->nrrs) |
387 | replacetextwithname(entry); |
388 | entry->addr= 0; |
389 | continue; |
390 | } |
391 | r= gettimeofday(&now,0); if (r) sysfail("gettimeofday"); |
392 | if (forever) { |
393 | tv= 0; |
394 | } else if (!timercmp(&now,&entry->printbefore,<)) { |
395 | entry->addr= 0; |
396 | continue; |
397 | } else { |
41559f53 |
398 | tvbuf.tv_sec= entry->printbefore.tv_sec - now.tv_sec - 1; |
399 | tvbuf.tv_usec= entry->printbefore.tv_usec - now.tv_usec + 1000000; |
2953d358 |
400 | tvbuf.tv_sec += tvbuf.tv_usec / 1000000; |
401 | tvbuf.tv_usec %= 1000000; |
402 | tv= &tvbuf; |
403 | } |
404 | adns_beforeselect(ads,&maxfd,&readfds,&writefds,&exceptfds, |
405 | &tv,&tvbuf,&now); |
406 | } |
407 | if (outblocked) FD_SET(1,&writefds); |
41559f53 |
408 | if (!inputeof && outqueuelen<1024) FD_SET(0,&readfds); |
2953d358 |
409 | |
410 | r= select(maxfd,&readfds,&writefds,&exceptfds,tv); |
411 | if (r < 0) { if (r == EINTR) continue; else sysfail("select"); } |
412 | |
413 | r= gettimeofday(&now,0); if (r) sysfail("gettimeofday"); |
414 | adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,&now); |
415 | checkadnsqueries(); |
416 | |
417 | if (FD_ISSET(0,&readfds)) { |
418 | if (!forever) { |
419 | printbefore= now; |
420 | timevaladd(&printbefore,timeout); |
421 | } |
422 | readstdin(); |
423 | } else if (FD_ISSET(1,&writefds)) { |
424 | outblocked= 0; |
425 | } |
426 | } |
2953d358 |
427 | if (nonblock(0,0)) sysfail("un-nonblock stdin"); |
428 | if (nonblock(1,0)) sysfail("un-nonblock stdout"); |
41559f53 |
429 | if (ferror(stdin) || fclose(stdin)) sysfail("read stdin"); |
430 | if (fclose(stdout)) sysfail("close stdout"); |
592aa664 |
431 | exit(0); |
432 | } |