3 * - configuration file parsing
4 * - management of global state
7 * This file is part of adns, which is
8 * Copyright (C) 1997-2000,2003,2006,2014-2016,2020 Ian Jackson
9 * Copyright (C) 2014 Mark Wooding
10 * Copyright (C) 1999-2000,2003,2006 Tony Finch
11 * Copyright (C) 1991 Massachusetts Institute of Technology
12 * (See the file INSTALL for full details.)
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 3, or (at your option)
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, write to the Free Software Foundation.
34 #include <sys/types.h>
36 #include <sys/socket.h>
37 #include <netinet/in.h>
38 #include <arpa/inet.h>
42 static void readconfig(adns_state ads, const char *filename, int warnmissing);
44 static void addserver(adns_state ads, const struct sockaddr *sa, int salen) {
47 char buf[ADNS_ADDR2TEXT_BUFLEN];
49 for (i=0; i<ads->nservers; i++) {
50 if (adns__sockaddrs_equal(sa, &ads->servers[i].addr.sa)) {
51 adns__debug(ads,-1,0,"duplicate nameserver %s ignored",
52 adns__sockaddr_ntoa(sa, buf));
57 if (ads->nservers>=MAXSERVERS) {
58 adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
59 adns__sockaddr_ntoa(sa, buf));
63 ss= ads->servers+ads->nservers;
64 assert(salen <= sizeof(ss->addr));
66 memcpy(&ss->addr, sa, salen);
70 static void freesearchlist(adns_state ads) {
71 if (ads->nsearchlist) free(*ads->searchlist);
72 free(ads->searchlist);
75 static void saveerr(adns_state ads, int en) {
76 if (!ads->configerrno) ads->configerrno= en;
79 static void configparseerr(adns_state ads, const char *fn, int lno,
80 const char *fmt, ...) {
84 if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
86 if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
87 else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
89 adns__vlprintf(ads,fmt,al);
91 adns__lprintf(ads,"\n");
94 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
98 while (ctype_whitespace(*p)) p++;
102 while (*q && !ctype_whitespace(*q)) q++;
111 static void ccf_nameserver(adns_state ads, const char *fn,
112 int lno, const char *buf) {
114 char addrbuf[ADNS_ADDR2TEXT_BUFLEN];
118 salen= sizeof(a.addr);
119 err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&salen);
125 configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
128 configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
132 adns__debug(ads,-1,0,"using nameserver %s",
133 adns__sockaddr_ntoa(&a.addr.sa, addrbuf));
134 addserver(ads,&a.addr.sa,salen);
137 static void ccf_search(adns_state ads, const char *fn,
138 int lno, const char *buf) {
139 const char *bufp, *word;
140 char *newchars, **newptrs, **pp;
148 while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
151 newptrs= malloc(sizeof(char*)*count);
152 if (!newptrs) { saveerr(ads,errno); return; }
154 newchars= malloc(tl);
155 if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
164 while (nextword(&bufp,&word,&l)) {
166 memcpy(newchars,word,l);
172 ads->nsearchlist= count;
173 ads->searchlist= newptrs;
176 static int gen_pton(const char *text, int want_af, adns_sockaddr *a) {
181 err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
183 if (err) { assert(err == EINVAL); return 0; }
184 if (want_af != AF_UNSPEC && a->sa.sa_family != want_af) return 0;
188 static void ccf_sortlist(adns_state ads, const char *fn,
189 int lno, const char *buf) {
191 char tbuf[200], *slash, *ep;
192 const char *maskwhat;
200 while (nextword(&buf,&word,&l)) {
201 if (ads->nsortlist >= MAXSORTLIST) {
202 adns__diag(ads,-1,0,"too many sortlist entries,"
203 " ignoring %.*s onwards",l,word);
207 if (l >= sizeof(tbuf)) {
208 configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
212 memcpy(tbuf,word,l); tbuf[l]= 0;
213 slash= strchr(tbuf,'/');
214 if (slash) *slash++= 0;
216 sl= &ads->sortlist[ads->nsortlist];
217 if (!gen_pton(tbuf, AF_UNSPEC, &sl->base)) {
218 configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
223 if (slash[strspn(slash, "0123456789")]) {
225 if (!gen_pton(slash, sl->base.sa.sa_family, &sl->mask)) {
226 configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
230 maskwhat = "prefix length";
231 unsigned long prefixlen = strtoul(slash,&ep,10);
232 if (*ep || prefixlen>adns__addr_width(sl->base.sa.sa_family)) {
233 configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
237 sl->mask.sa.sa_family= sl->base.sa.sa_family;
238 adns__prefix_mask(&sl->mask, initial);
241 maskwhat = "implied prefix length";
242 initial= adns__guess_prefix_length(&sl->base);
244 configparseerr(ads,fn,lno, "network address `%s'"
245 " in sortlist is not in classed ranges,"
246 " must specify mask explicitly", tbuf);
249 sl->mask.sa.sa_family= sl->base.sa.sa_family;
250 adns__prefix_mask(&sl->mask, initial);
253 if (!adns__addr_matches(sl->base.sa.sa_family,
254 adns__sockaddr_addr(&sl->base.sa),
255 &sl->base,&sl->mask)) {
257 configparseerr(ads,fn,lno, "%s %d in sortlist"
258 " overlaps address `%s'",maskwhat,initial,tbuf);
260 configparseerr(ads,fn,lno, "%s `%s' in sortlist"
261 " overlaps address `%s'",maskwhat,slash,tbuf);
270 static void ccf_options(adns_state ads, const char *fn,
271 int lno, const char *buf) {
272 const char *opt, *word, *endword, *endopt;
279 #define WORD__IS(s,op) ((endword-word) op (sizeof(s)-1) && \
280 !memcmp(word,s,(sizeof(s)-1)))
281 #define WORD_IS(s) (WORD__IS(s,==))
282 #define WORD_STARTS(s) (WORD__IS(s,>=) ? ((word+=sizeof(s)-1)) : 0)
284 while (nextword(&buf,&word,&l)) {
286 endopt=endword=word+l;
287 if (WORD_IS("debug")) {
288 ads->iflags |= adns_if_debug;
291 if (WORD_STARTS("ndots:")) {
292 v= strtoul(word,&ep,10);
293 if (ep==word || ep != endword || v > INT_MAX) {
294 configparseerr(ads,fn,lno,"option `%.*s' malformed"
295 " or has bad value",l,opt);
301 if (WORD_STARTS("adns_checkc:")) {
302 if (WORD_IS("none")) {
303 ads->iflags &= ~adns_if_checkc_freq;
304 ads->iflags |= adns_if_checkc_entex;
305 } else if (WORD_IS("entex")) {
306 ads->iflags &= ~adns_if_checkc_freq;
307 ads->iflags |= adns_if_checkc_entex;
308 } else if (WORD_IS("freq")) {
309 ads->iflags |= adns_if_checkc_freq;
311 configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
312 "(must be none, entex or freq", word);
316 if (WORD_STARTS("adns_af:")) {
317 ads->iflags &= ~adns_if_afmask;
318 if (!WORD_IS("any")) for (;;) {
319 const char *comma= memchr(word,',',endopt-word);
320 endword=comma?comma:endopt;
322 ads->iflags |= adns_if_permit_ipv4;
323 else if (WORD_IS("ipv6"))
324 ads->iflags |= adns_if_permit_ipv6;
326 if (ads->config_report_unknown)
327 adns__diag(ads,-1,0,"%s:%d: "
328 "option adns_af has bad value or entry `%.*s' "
329 "(option must be `any', or list of `ipv4',`ipv6')",
330 fn,lno, (int)(endword-word),word);
338 if (WORD_IS("adns_ignoreunkcfg")) {
339 ads->config_report_unknown=0;
342 if (/* adns's query strategy is not configurable */
343 WORD_STARTS("timeout:") ||
344 WORD_STARTS("attempts:") ||
346 /* adns provides the application with knob for this */
347 WORD_IS("no-check-names") ||
348 /* adns normally does IPv6 if the application wants it; control
349 * this with the adns_af: option if you like */
351 /* adns does not do edns0 and this is not a problem */
354 if (ads->config_report_unknown)
355 adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,opt);
363 static void ccf_clearnss(adns_state ads, const char *fn,
364 int lno, const char *buf) {
368 static void ccf_include(adns_state ads, const char *fn,
369 int lno, const char *buf) {
371 configparseerr(ads,fn,lno,"`include' directive with no filename");
374 readconfig(ads,buf,1);
377 static void ccf_lookup(adns_state ads, const char *fn, int lno,
384 configparseerr(ads,fn,lno,"`lookup' directive with no databases");
388 while (nextword(&buf,&word,&l)) {
389 if (l==4 && !memcmp(word,"bind",4)) {
391 } else if (l==4 && !memcmp(word,"file",4)) {
392 /* ignore this and hope /etc/hosts is not essential */
393 } else if (l==2 && !memcmp(word,"yp",2)) {
394 adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
397 if (ads->config_report_unknown)
398 adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
404 adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
407 static void ccf_ignore(adns_state ads, const char *fn, int lno,
411 static const struct configcommandinfo {
413 void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
414 } configcommandinfos[]= {
415 { "nameserver", ccf_nameserver },
416 { "domain", ccf_search },
417 { "search", ccf_search },
418 { "sortlist", ccf_sortlist },
419 { "options", ccf_options },
420 { "clearnameservers", ccf_clearnss },
421 { "include", ccf_include },
422 { "lookup", ccf_lookup }, /* OpenBSD */
423 { "lwserver", ccf_ignore }, /* BIND9 lwresd */
432 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
433 int lno, char *buf, int buflen) {
434 FILE *file= src_io->file;
442 for (;;) { /* loop over chars */
444 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
449 adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
451 } else if (c == '\n') {
453 } else if (c == EOF) {
456 adns__diag(ads,-1,0,"%s:%d: read error: %s",
457 filename,lno,strerror(errno));
473 while ((c= getc(file)) != EOF && c != '\n');
477 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
478 int lno, char *buf, int buflen) {
479 const char *cp= src_io->text;
482 if (!cp || !*cp) return -1;
484 if (*cp == ';' || *cp == '\n') cp++;
485 l= strcspn(cp,";\n");
489 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
499 static void readconfiggeneric(adns_state ads, const char *filename,
500 int (*getline)(adns_state ads, getline_ctx*,
501 const char *filename, int lno,
502 char *buf, int buflen),
503 /* Returns >=0 for success, -1 for EOF or error
504 * (error will have been reported), or -2 for
505 * bad line was encountered, try again.
507 getline_ctx gl_ctx) {
508 char linebuf[2000], *p, *q;
510 const struct configcommandinfo *ccip;
513 (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
515 if (l == -2) continue;
516 while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
519 while (ctype_whitespace(*p)) p++;
520 if (*p == '#' || *p == ';' || !*p) continue;
522 while (*q && !ctype_whitespace(*q)) q++;
524 for (ccip=configcommandinfos;
526 !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
529 if (ads->config_report_unknown)
530 adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
531 filename,lno,(int)(q-p),p);
534 while (ctype_whitespace(*q)) q++;
535 ccip->fn(ads,filename,lno,q);
539 static const char *instrum_getenv(adns_state ads, const char *envvar) {
542 value= getenv(envvar);
543 if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
544 else adns__debug(ads,-1,0,"environment variable %s"
545 " set to `%s'",envvar,value);
549 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
552 gl_ctx.file= fopen(filename,"r");
554 if (errno == ENOENT) {
556 adns__debug(ads,-1,0, "configuration file"
557 " `%s' does not exist",filename);
561 adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
562 filename,strerror(errno));
566 readconfiggeneric(ads,filename,gl_file,gl_ctx);
571 static void readconfigtext(adns_state ads, const char *text,
572 const char *showname) {
576 readconfiggeneric(ads,showname,gl_text,gl_ctx);
579 static void readconfigenv(adns_state ads, const char *envvar) {
580 const char *filename;
582 if (ads->iflags & adns_if_noenv) {
583 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
586 filename= instrum_getenv(ads,envvar);
587 if (filename) readconfig(ads,filename,1);
590 static void readconfigenvtext(adns_state ads, const char *envvar) {
591 const char *textdata;
593 if (ads->iflags & adns_if_noenv) {
594 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
597 textdata= instrum_getenv(ads,envvar);
598 if (textdata) readconfigtext(ads,textdata,envvar);
602 int adns__setnonblock(adns_state ads, int fd) {
605 r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
607 r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
611 static int init_begin(adns_state *ads_r, adns_initflags flags,
612 adns_logcallbackfn *logfn, void *logfndata) {
616 if (flags & ~(adns_initflags)(0x4fff))
617 /* 0x4000 is reserved for `harmless' future expansion */
620 ads= malloc(sizeof(*ads)); if (!ads) return errno;
624 ads->logfndata= logfndata;
626 LIST_INIT(ads->udpw);
627 LIST_INIT(ads->tcpw);
628 LIST_INIT(ads->childw);
629 LIST_INIT(ads->output);
630 LIST_INIT(ads->intdone);
635 adns__vbuf_init(&ads->tcpsend);
636 adns__vbuf_init(&ads->tcprecv);
637 ads->tcprecv_skip= 0;
638 ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
640 ads->tcpstate= server_disconnected;
641 timerclear(&ads->tcptimeout);
643 ads->config_report_unknown=1;
646 ads->rand48xsubi[0]= pid;
647 ads->rand48xsubi[1]= (unsigned long)pid >> 16;
648 ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
654 static int init_finish(adns_state ads) {
655 struct sockaddr_in sin;
656 struct protoent *proto;
657 struct udpsocket *udp;
661 if (!ads->nservers) {
662 if (ads->logfn && ads->iflags & adns_if_debug)
663 adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
664 memset(&sin, 0, sizeof(sin));
665 sin.sin_family = AF_INET;
666 sin.sin_port = htons(DNS_PORT);
667 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
668 addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
671 proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
673 for (i=0; i<ads->nservers; i++) {
674 if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
676 assert(ads->nudpsockets < MAXUDP);
677 udp= &ads->udpsockets[ads->nudpsockets];
678 udp->af= ads->servers[i].addr.sa.sa_family;
679 udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
680 if (udp->fd < 0) { r= errno; goto x_free; }
682 r= adns__setnonblock(ads,udp->fd);
683 if (r) { r= errno; goto x_closeudp; }
689 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
695 static void init_abort(adns_state ads) {
696 if (ads->nsearchlist) {
697 free(ads->searchlist[0]);
698 free(ads->searchlist);
703 static void logfn_file(adns_state ads, void *logfndata,
704 const char *fmt, va_list al) {
705 vfprintf(logfndata,fmt,al);
708 static int init_files(adns_state *ads_r, adns_initflags flags,
709 adns_logcallbackfn *logfn, void *logfndata) {
711 const char *res_options, *adns_res_options;
714 r= init_begin(&ads, flags, logfn, logfndata);
717 res_options= instrum_getenv(ads,"RES_OPTIONS");
718 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
719 ccf_options(ads,"RES_OPTIONS",-1,res_options);
720 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
722 readconfig(ads,"/etc/resolv.conf",1);
723 readconfig(ads,"/etc/resolv-adns.conf",0);
724 readconfigenv(ads,"RES_CONF");
725 readconfigenv(ads,"ADNS_RES_CONF");
727 readconfigenvtext(ads,"RES_CONF_TEXT");
728 readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
730 ccf_options(ads,"RES_OPTIONS",-1,res_options);
731 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
733 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
734 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
736 if (ads->configerrno && ads->configerrno != EINVAL) {
745 adns__consistency(ads,0,cc_exit);
750 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
751 return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
754 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
755 adns_logcallbackfn *logfn, void *logfndata,
756 const char *configtext) {
760 r= init_begin(&ads, flags, logfn, logfndata);
763 readconfigtext(ads,configtext,"<supplied configuration text>");
764 if (ads->configerrno) {
770 r= init_finish(ads); if (r) return r;
771 adns__consistency(ads,0,cc_exit);
776 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
777 FILE *diagfile, const char *configtext) {
778 return init_strcfg(ads_r, flags,
779 diagfile ? logfn_file : 0, diagfile,
783 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
784 const char *configtext /*0=>use default config files*/,
785 adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
786 void *logfndata /*0 with logfn==0 => discard*/) {
787 if (!logfn && logfndata)
790 return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
792 return init_files(newstate_r, flags, logfn, logfndata);
795 static void cancel_all(adns_query qu) {
796 if (!qu->parent) adns__cancel(qu);
797 else cancel_all(qu->parent);
800 void adns_finish(adns_state ads) {
802 adns__consistency(ads,0,cc_enter);
804 if (ads->udpw.head) cancel_all(ads->udpw.head);
805 else if (ads->tcpw.head) cancel_all(ads->tcpw.head);
806 else if (ads->childw.head) cancel_all(ads->childw.head);
807 else if (ads->output.head) cancel_all(ads->output.head);
808 else if (ads->intdone.head) cancel_all(ads->output.head);
811 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
812 if (ads->tcpsocket >= 0) close(ads->tcpsocket);
813 adns__vbuf_free(&ads->tcpsend);
814 adns__vbuf_free(&ads->tcprecv);
819 void adns_forallqueries_begin(adns_state ads) {
820 adns__consistency(ads,0,cc_enter);
822 ads->udpw.head ? ads->udpw.head :
823 ads->tcpw.head ? ads->tcpw.head :
824 ads->childw.head ? ads->childw.head :
828 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
831 adns__consistency(ads,0,cc_enter);
832 nqu= ads->forallnext;
838 } else if (qu == ads->udpw.tail) {
840 ads->tcpw.head ? ads->tcpw.head :
841 ads->childw.head ? ads->childw.head :
843 } else if (qu == ads->tcpw.tail) {
845 ads->childw.head ? ads->childw.head :
847 } else if (qu == ads->childw.tail) {
848 nqu= ads->output.head;
852 if (!qu->parent) break;
854 ads->forallnext= nqu;
855 if (context_r) *context_r= qu->ctx.ext;