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 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; }
150 newptrs= malloc(sizeof(char*)*count);
151 if (!newptrs) { saveerr(ads,errno); return; }
153 newchars= malloc(tl);
154 if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
158 while (nextword(&bufp,&word,&l)) {
160 memcpy(newchars,word,l);
166 ads->nsearchlist= count;
167 ads->searchlist= newptrs;
170 static int gen_pton(const char *text, int want_af, adns_sockaddr *a) {
175 err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
177 if (err) { assert(err == EINVAL); return 0; }
178 if (want_af != AF_UNSPEC && a->sa.sa_family != want_af) return 0;
182 static void ccf_sortlist(adns_state ads, const char *fn,
183 int lno, const char *buf) {
185 char tbuf[200], *slash, *ep;
186 const char *maskwhat;
194 while (nextword(&buf,&word,&l)) {
195 if (ads->nsortlist >= MAXSORTLIST) {
196 adns__diag(ads,-1,0,"too many sortlist entries,"
197 " ignoring %.*s onwards",l,word);
201 if (l >= sizeof(tbuf)) {
202 configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
206 memcpy(tbuf,word,l); tbuf[l]= 0;
207 slash= strchr(tbuf,'/');
208 if (slash) *slash++= 0;
210 sl= &ads->sortlist[ads->nsortlist];
211 if (!gen_pton(tbuf, AF_UNSPEC, &sl->base)) {
212 configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
217 if (slash[strspn(slash, "0123456789")]) {
219 if (!gen_pton(slash, sl->base.sa.sa_family, &sl->mask)) {
220 configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
224 maskwhat = "prefix length";
225 initial= strtoul(slash,&ep,10);
226 if (*ep || initial>adns__addr_width(sl->base.sa.sa_family)) {
227 configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
230 sl->mask.sa.sa_family= sl->base.sa.sa_family;
231 adns__prefix_mask(&sl->mask, initial);
234 maskwhat = "implied prefix length";
235 initial= adns__guess_prefix_length(&sl->base);
237 configparseerr(ads,fn,lno, "network address `%s'"
238 " in sortlist is not in classed ranges,"
239 " must specify mask explicitly", tbuf);
242 sl->mask.sa.sa_family= sl->base.sa.sa_family;
243 adns__prefix_mask(&sl->mask, initial);
246 if (!adns__addr_matches(sl->base.sa.sa_family,
247 adns__sockaddr_addr(&sl->base.sa),
248 &sl->base,&sl->mask)) {
250 configparseerr(ads,fn,lno, "%s %d in sortlist"
251 " overlaps address `%s'",maskwhat,initial,tbuf);
253 configparseerr(ads,fn,lno, "%s `%s' in sortlist"
254 " overlaps address `%s'",maskwhat,slash,tbuf);
263 static void ccf_options(adns_state ads, const char *fn,
264 int lno, const char *buf) {
265 const char *opt, *word, *endword, *endopt;
272 #define WORD__IS(s,op) ((endword-word) op (sizeof(s)-1) && \
273 !memcmp(word,s,(sizeof(s)-1)))
274 #define WORD_IS(s) (WORD__IS(s,==))
275 #define WORD_STARTS(s) (WORD__IS(s,>=) ? ((word+=sizeof(s)-1)) : 0)
277 while (nextword(&buf,&word,&l)) {
279 endopt=endword=word+l;
280 if (WORD_IS("debug")) {
281 ads->iflags |= adns_if_debug;
284 if (WORD_STARTS("ndots:")) {
285 v= strtoul(word,&ep,10);
286 if (ep==word || ep != endword || v > INT_MAX) {
287 configparseerr(ads,fn,lno,"option `%.*s' malformed"
288 " or has bad value",l,opt);
294 if (WORD_STARTS("adns_checkc:")) {
295 if (WORD_IS("none")) {
296 ads->iflags &= ~adns_if_checkc_freq;
297 ads->iflags |= adns_if_checkc_entex;
298 } else if (WORD_IS("entex")) {
299 ads->iflags &= ~adns_if_checkc_freq;
300 ads->iflags |= adns_if_checkc_entex;
301 } else if (WORD_IS("freq")) {
302 ads->iflags |= adns_if_checkc_freq;
304 configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
305 "(must be none, entex or freq", word);
309 if (WORD_STARTS("adns_af:")) {
310 ads->iflags &= ~adns_if_afmask;
311 if (!WORD_IS("any")) for (;;) {
312 const char *comma= memchr(word,',',endopt-word);
313 endword=comma?comma:endopt;
315 ads->iflags |= adns_if_permit_ipv4;
316 else if (WORD_IS("ipv6"))
317 ads->iflags |= adns_if_permit_ipv6;
319 if (ads->config_report_unknown)
320 adns__diag(ads,-1,0,"%s:%d: "
321 "option adns_af has bad value or entry `%.*s' "
322 "(option must be `any', or list of `ipv4',`ipv6')",
323 fn,lno, (int)(endword-word),word);
331 if (WORD_IS("adns_ignoreunkcfg")) {
332 ads->config_report_unknown=0;
335 if (/* adns's query strategy is not configurable */
336 WORD_STARTS("timeout:") ||
337 WORD_STARTS("attempts:") ||
339 /* adns provides the application with knob for this */
340 WORD_IS("no-check-names") ||
341 /* adns normally does IPv6 if the application wants it; control
342 * this with the adns_af: option if you like */
344 /* adns does not do edns0 and this is not a problem */
347 if (ads->config_report_unknown)
348 adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,opt);
356 static void ccf_clearnss(adns_state ads, const char *fn,
357 int lno, const char *buf) {
361 static void ccf_include(adns_state ads, const char *fn,
362 int lno, const char *buf) {
364 configparseerr(ads,fn,lno,"`include' directive with no filename");
367 readconfig(ads,buf,1);
370 static void ccf_lookup(adns_state ads, const char *fn, int lno,
377 configparseerr(ads,fn,lno,"`lookup' directive with no databases");
381 while (nextword(&buf,&word,&l)) {
382 if (l==4 && !memcmp(word,"bind",4)) {
384 } else if (l==4 && !memcmp(word,"file",4)) {
385 /* ignore this and hope /etc/hosts is not essential */
386 } else if (l==2 && !memcmp(word,"yp",2)) {
387 adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
390 if (ads->config_report_unknown)
391 adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
397 adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
400 static void ccf_ignore(adns_state ads, const char *fn, int lno,
404 static const struct configcommandinfo {
406 void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
407 } configcommandinfos[]= {
408 { "nameserver", ccf_nameserver },
409 { "domain", ccf_search },
410 { "search", ccf_search },
411 { "sortlist", ccf_sortlist },
412 { "options", ccf_options },
413 { "clearnameservers", ccf_clearnss },
414 { "include", ccf_include },
415 { "lookup", ccf_lookup }, /* OpenBSD */
416 { "lwserver", ccf_ignore }, /* BIND9 lwresd */
425 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
426 int lno, char *buf, int buflen) {
427 FILE *file= src_io->file;
435 for (;;) { /* loop over chars */
437 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
442 adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
444 } else if (c == '\n') {
446 } else if (c == EOF) {
449 adns__diag(ads,-1,0,"%s:%d: read error: %s",
450 filename,lno,strerror(errno));
466 while ((c= getc(file)) != EOF && c != '\n');
470 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
471 int lno, char *buf, int buflen) {
472 const char *cp= src_io->text;
475 if (!cp || !*cp) return -1;
477 if (*cp == ';' || *cp == '\n') cp++;
478 l= strcspn(cp,";\n");
482 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
492 static void readconfiggeneric(adns_state ads, const char *filename,
493 int (*getline)(adns_state ads, getline_ctx*,
494 const char *filename, int lno,
495 char *buf, int buflen),
496 /* Returns >=0 for success, -1 for EOF or error
497 * (error will have been reported), or -2 for
498 * bad line was encountered, try again.
500 getline_ctx gl_ctx) {
501 char linebuf[2000], *p, *q;
503 const struct configcommandinfo *ccip;
506 (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
508 if (l == -2) continue;
509 while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
512 while (ctype_whitespace(*p)) p++;
513 if (*p == '#' || *p == ';' || !*p) continue;
515 while (*q && !ctype_whitespace(*q)) q++;
517 for (ccip=configcommandinfos;
519 !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
522 if (ads->config_report_unknown)
523 adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
524 filename,lno,(int)(q-p),p);
527 while (ctype_whitespace(*q)) q++;
528 ccip->fn(ads,filename,lno,q);
532 static const char *instrum_getenv(adns_state ads, const char *envvar) {
535 value= getenv(envvar);
536 if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
537 else adns__debug(ads,-1,0,"environment variable %s"
538 " set to `%s'",envvar,value);
542 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
545 gl_ctx.file= fopen(filename,"r");
547 if (errno == ENOENT) {
549 adns__debug(ads,-1,0, "configuration file"
550 " `%s' does not exist",filename);
554 adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
555 filename,strerror(errno));
559 readconfiggeneric(ads,filename,gl_file,gl_ctx);
564 static void readconfigtext(adns_state ads, const char *text,
565 const char *showname) {
569 readconfiggeneric(ads,showname,gl_text,gl_ctx);
572 static void readconfigenv(adns_state ads, const char *envvar) {
573 const char *filename;
575 if (ads->iflags & adns_if_noenv) {
576 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
579 filename= instrum_getenv(ads,envvar);
580 if (filename) readconfig(ads,filename,1);
583 static void readconfigenvtext(adns_state ads, const char *envvar) {
584 const char *textdata;
586 if (ads->iflags & adns_if_noenv) {
587 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
590 textdata= instrum_getenv(ads,envvar);
591 if (textdata) readconfigtext(ads,textdata,envvar);
595 int adns__setnonblock(adns_state ads, int fd) {
598 r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
600 r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
604 static int init_begin(adns_state *ads_r, adns_initflags flags,
605 adns_logcallbackfn *logfn, void *logfndata) {
609 if (flags & ~(adns_initflags)(0x4fff))
610 /* 0x4000 is reserved for `harmless' future expansion */
613 ads= malloc(sizeof(*ads)); if (!ads) return errno;
617 ads->logfndata= logfndata;
619 LIST_INIT(ads->udpw);
620 LIST_INIT(ads->tcpw);
621 LIST_INIT(ads->childw);
622 LIST_INIT(ads->output);
623 LIST_INIT(ads->intdone);
628 adns__vbuf_init(&ads->tcpsend);
629 adns__vbuf_init(&ads->tcprecv);
630 ads->tcprecv_skip= 0;
631 ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
633 ads->tcpstate= server_disconnected;
634 timerclear(&ads->tcptimeout);
636 ads->config_report_unknown=1;
639 ads->rand48xsubi[0]= pid;
640 ads->rand48xsubi[1]= (unsigned long)pid >> 16;
641 ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
647 static int init_finish(adns_state ads) {
648 struct sockaddr_in sin;
649 struct protoent *proto;
650 struct udpsocket *udp;
654 if (!ads->nservers) {
655 if (ads->logfn && ads->iflags & adns_if_debug)
656 adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
657 memset(&sin, 0, sizeof(sin));
658 sin.sin_family = AF_INET;
659 sin.sin_port = htons(DNS_PORT);
660 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
661 addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
664 proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
666 for (i=0; i<ads->nservers; i++) {
667 if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
669 assert(ads->nudpsockets < MAXUDP);
670 udp= &ads->udpsockets[ads->nudpsockets];
671 udp->af= ads->servers[i].addr.sa.sa_family;
672 udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
673 if (udp->fd < 0) { r= errno; goto x_free; }
675 r= adns__setnonblock(ads,udp->fd);
676 if (r) { r= errno; goto x_closeudp; }
682 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
688 static void init_abort(adns_state ads) {
689 if (ads->nsearchlist) {
690 free(ads->searchlist[0]);
691 free(ads->searchlist);
696 static void logfn_file(adns_state ads, void *logfndata,
697 const char *fmt, va_list al) {
698 vfprintf(logfndata,fmt,al);
701 static int init_files(adns_state *ads_r, adns_initflags flags,
702 adns_logcallbackfn *logfn, void *logfndata) {
704 const char *res_options, *adns_res_options;
707 r= init_begin(&ads, flags, logfn, logfndata);
710 res_options= instrum_getenv(ads,"RES_OPTIONS");
711 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
712 ccf_options(ads,"RES_OPTIONS",-1,res_options);
713 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
715 readconfig(ads,"/etc/resolv.conf",1);
716 readconfig(ads,"/etc/resolv-adns.conf",0);
717 readconfigenv(ads,"RES_CONF");
718 readconfigenv(ads,"ADNS_RES_CONF");
720 readconfigenvtext(ads,"RES_CONF_TEXT");
721 readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
723 ccf_options(ads,"RES_OPTIONS",-1,res_options);
724 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
726 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
727 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
729 if (ads->configerrno && ads->configerrno != EINVAL) {
738 adns__consistency(ads,0,cc_entex);
743 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
744 return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
747 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
748 adns_logcallbackfn *logfn, void *logfndata,
749 const char *configtext) {
753 r= init_begin(&ads, flags, logfn, logfndata);
756 readconfigtext(ads,configtext,"<supplied configuration text>");
757 if (ads->configerrno) {
763 r= init_finish(ads); if (r) return r;
764 adns__consistency(ads,0,cc_entex);
769 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
770 FILE *diagfile, const char *configtext) {
771 return init_strcfg(ads_r, flags,
772 diagfile ? logfn_file : 0, diagfile,
776 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
777 const char *configtext /*0=>use default config files*/,
778 adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
779 void *logfndata /*0 with logfn==0 => discard*/) {
780 if (!logfn && logfndata)
783 return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
785 return init_files(newstate_r, flags, logfn, logfndata);
788 void adns_finish(adns_state ads) {
790 adns__consistency(ads,0,cc_entex);
792 if (ads->udpw.head) adns__cancel(ads->udpw.head);
793 else if (ads->tcpw.head) adns__cancel(ads->tcpw.head);
794 else if (ads->childw.head) adns__cancel(ads->childw.head);
795 else if (ads->output.head) adns__cancel(ads->output.head);
796 else if (ads->intdone.head) adns__cancel(ads->output.head);
799 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
800 if (ads->tcpsocket >= 0) close(ads->tcpsocket);
801 adns__vbuf_free(&ads->tcpsend);
802 adns__vbuf_free(&ads->tcprecv);
807 void adns_forallqueries_begin(adns_state ads) {
808 adns__consistency(ads,0,cc_entex);
810 ads->udpw.head ? ads->udpw.head :
811 ads->tcpw.head ? ads->tcpw.head :
812 ads->childw.head ? ads->childw.head :
816 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
819 adns__consistency(ads,0,cc_entex);
820 nqu= ads->forallnext;
826 } else if (qu == ads->udpw.tail) {
828 ads->tcpw.head ? ads->tcpw.head :
829 ads->childw.head ? ads->childw.head :
831 } else if (qu == ads->tcpw.tail) {
833 ads->childw.head ? ads->childw.head :
835 } else if (qu == ads->childw.tail) {
836 nqu= ads->output.head;
840 if (!qu->parent) break;
842 ads->forallnext= nqu;
843 if (context_r) *context_r= qu->ctx.ext;