3 * - configuration file parsing
4 * - management of global state
7 * This file is part of adns, which is Copyright Ian Jackson
8 * and contributors (see the file INSTALL for full details).
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 3, or (at your option)
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software Foundation.
30 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <netinet/in.h>
34 #include <arpa/inet.h>
38 static void readconfig(adns_state ads, const char *filename, int warnmissing);
40 static void addserver(adns_state ads, const struct sockaddr *sa, int salen) {
43 char buf[ADNS_ADDR2TEXT_BUFLEN];
45 for (i=0; i<ads->nservers; i++) {
46 if (adns__sockaddrs_equal(sa, &ads->servers[i].addr.sa)) {
47 adns__debug(ads,-1,0,"duplicate nameserver %s ignored",
48 adns__sockaddr_ntoa(sa, buf));
53 if (ads->nservers>=MAXSERVERS) {
54 adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
55 adns__sockaddr_ntoa(sa, buf));
59 ss= ads->servers+ads->nservers;
60 assert(salen <= sizeof(ss->addr));
62 memcpy(&ss->addr, sa, salen);
66 static void freesearchlist(adns_state ads) {
67 if (ads->nsearchlist) free(*ads->searchlist);
68 free(ads->searchlist);
71 static void saveerr(adns_state ads, int en) {
72 if (!ads->configerrno) ads->configerrno= en;
75 static void configparseerr(adns_state ads, const char *fn, int lno,
76 const char *fmt, ...) {
80 if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
82 if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
83 else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
85 adns__vlprintf(ads,fmt,al);
87 adns__lprintf(ads,"\n");
90 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
94 while (ctype_whitespace(*p)) p++;
98 while (*q && !ctype_whitespace(*q)) q++;
107 static void ccf_nameserver(adns_state ads, const char *fn,
108 int lno, const char *buf) {
110 char addrbuf[ADNS_ADDR2TEXT_BUFLEN];
114 salen= sizeof(a.addr);
115 err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&salen);
121 configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
124 configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
128 adns__debug(ads,-1,0,"using nameserver %s",
129 adns__sockaddr_ntoa(&a.addr.sa, addrbuf));
130 addserver(ads,&a.addr.sa,salen);
133 static void ccf_search(adns_state ads, const char *fn,
134 int lno, const char *buf) {
135 const char *bufp, *word;
136 char *newchars, **newptrs, **pp;
144 while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
147 newptrs= malloc(sizeof(char*)*count);
148 if (!newptrs) { saveerr(ads,errno); return; }
150 newchars= malloc(tl);
151 if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
160 while (nextword(&bufp,&word,&l)) {
162 memcpy(newchars,word,l);
168 ads->nsearchlist= count;
169 ads->searchlist= newptrs;
172 static int gen_pton(const char *text, int want_af, adns_sockaddr *a) {
177 err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
179 if (err) { assert(err == EINVAL); return 0; }
180 if (want_af != AF_UNSPEC && a->sa.sa_family != want_af) return 0;
184 static void ccf_sortlist(adns_state ads, const char *fn,
185 int lno, const char *buf) {
187 char tbuf[200], *slash, *ep;
188 const char *maskwhat;
196 while (nextword(&buf,&word,&l)) {
197 if (ads->nsortlist >= MAXSORTLIST) {
198 adns__diag(ads,-1,0,"too many sortlist entries,"
199 " ignoring %.*s onwards",l,word);
203 if (l >= sizeof(tbuf)) {
204 configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
208 memcpy(tbuf,word,l); tbuf[l]= 0;
209 slash= strchr(tbuf,'/');
210 if (slash) *slash++= 0;
212 sl= &ads->sortlist[ads->nsortlist];
213 if (!gen_pton(tbuf, AF_UNSPEC, &sl->base)) {
214 configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
219 if (slash[strspn(slash, "0123456789")]) {
221 if (!gen_pton(slash, sl->base.sa.sa_family, &sl->mask)) {
222 configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
226 maskwhat = "prefix length";
227 unsigned long prefixlen = strtoul(slash,&ep,10);
228 if (*ep || prefixlen>adns__addr_width(sl->base.sa.sa_family)) {
229 configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
233 sl->mask.sa.sa_family= sl->base.sa.sa_family;
234 adns__prefix_mask(&sl->mask, initial);
237 maskwhat = "implied prefix length";
238 initial= adns__guess_prefix_length(&sl->base);
240 configparseerr(ads,fn,lno, "network address `%s'"
241 " in sortlist is not in classed ranges,"
242 " must specify mask explicitly", tbuf);
245 sl->mask.sa.sa_family= sl->base.sa.sa_family;
246 adns__prefix_mask(&sl->mask, initial);
249 if (!adns__addr_matches(sl->base.sa.sa_family,
250 adns__sockaddr_addr(&sl->base.sa),
251 &sl->base,&sl->mask)) {
253 configparseerr(ads,fn,lno, "%s %d in sortlist"
254 " overlaps address `%s'",maskwhat,initial,tbuf);
256 configparseerr(ads,fn,lno, "%s `%s' in sortlist"
257 " overlaps address `%s'",maskwhat,slash,tbuf);
266 static void ccf_options(adns_state ads, const char *fn,
267 int lno, const char *buf) {
268 const char *opt, *word, *endword, *endopt;
275 #define WORD__IS(s,op) ((endword-word) op (sizeof(s)-1) && \
276 !memcmp(word,s,(sizeof(s)-1)))
277 #define WORD_IS(s) (WORD__IS(s,==))
278 #define WORD_STARTS(s) (WORD__IS(s,>=) ? ((word+=sizeof(s)-1)) : 0)
280 while (nextword(&buf,&word,&l)) {
282 endopt=endword=word+l;
283 if (WORD_IS("debug")) {
284 ads->iflags |= adns_if_debug;
287 if (WORD_STARTS("ndots:")) {
288 v= strtoul(word,&ep,10);
289 if (ep==word || ep != endword || v > INT_MAX) {
290 configparseerr(ads,fn,lno,"option `%.*s' malformed"
291 " or has bad value",l,opt);
297 if (WORD_STARTS("adns_checkc:")) {
298 if (WORD_IS("none")) {
299 ads->iflags &= ~adns_if_checkc_freq;
300 ads->iflags |= adns_if_checkc_entex;
301 } else if (WORD_IS("entex")) {
302 ads->iflags &= ~adns_if_checkc_freq;
303 ads->iflags |= adns_if_checkc_entex;
304 } else if (WORD_IS("freq")) {
305 ads->iflags |= adns_if_checkc_freq;
307 configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
308 "(must be none, entex or freq", word);
312 if (WORD_STARTS("adns_af:")) {
313 ads->iflags &= ~adns_if_afmask;
314 if (!WORD_IS("any")) for (;;) {
315 const char *comma= memchr(word,',',endopt-word);
316 endword=comma?comma:endopt;
318 ads->iflags |= adns_if_permit_ipv4;
319 else if (WORD_IS("ipv6"))
320 ads->iflags |= adns_if_permit_ipv6;
322 if (ads->config_report_unknown)
323 adns__diag(ads,-1,0,"%s:%d: "
324 "option adns_af has bad value or entry `%.*s' "
325 "(option must be `any', or list of `ipv4',`ipv6')",
326 fn,lno, (int)(endword-word),word);
334 if (WORD_IS("adns_ignoreunkcfg")) {
335 ads->config_report_unknown=0;
338 if (/* adns's query strategy is not configurable */
339 WORD_STARTS("timeout:") ||
340 WORD_STARTS("attempts:") ||
342 /* adns provides the application with knob for this */
343 WORD_IS("no-check-names") ||
344 /* adns normally does IPv6 if the application wants it; control
345 * this with the adns_af: option if you like */
347 /* adns trusts the resolver anyway */
348 WORD_IS("trust-ad") ||
349 /* adns does not do edns0 and this is not a problem */
352 if (ads->config_report_unknown)
353 adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,opt);
361 static void ccf_clearnss(adns_state ads, const char *fn,
362 int lno, const char *buf) {
366 static void ccf_include(adns_state ads, const char *fn,
367 int lno, const char *buf) {
369 configparseerr(ads,fn,lno,"`include' directive with no filename");
372 readconfig(ads,buf,1);
375 static void ccf_lookup(adns_state ads, const char *fn, int lno,
382 configparseerr(ads,fn,lno,"`lookup' directive with no databases");
386 while (nextword(&buf,&word,&l)) {
387 if (l==4 && !memcmp(word,"bind",4)) {
389 } else if (l==4 && !memcmp(word,"file",4)) {
390 /* ignore this and hope /etc/hosts is not essential */
391 } else if (l==2 && !memcmp(word,"yp",2)) {
392 adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
395 if (ads->config_report_unknown)
396 adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
402 adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
405 static void ccf_ignore(adns_state ads, const char *fn, int lno,
409 static const struct configcommandinfo {
411 void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
412 } configcommandinfos[]= {
413 { "nameserver", ccf_nameserver },
414 { "domain", ccf_search },
415 { "search", ccf_search },
416 { "sortlist", ccf_sortlist },
417 { "options", ccf_options },
418 { "clearnameservers", ccf_clearnss },
419 { "include", ccf_include },
420 { "lookup", ccf_lookup }, /* OpenBSD */
421 { "lwserver", ccf_ignore }, /* BIND9 lwresd */
430 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
431 int lno, char *buf, int buflen) {
432 FILE *file= src_io->file;
440 for (;;) { /* loop over chars */
442 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
447 adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
449 } else if (c == '\n') {
451 } else if (c == EOF) {
454 adns__diag(ads,-1,0,"%s:%d: read error: %s",
455 filename,lno,strerror(errno));
471 while ((c= getc(file)) != EOF && c != '\n');
475 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
476 int lno, char *buf, int buflen) {
477 const char *cp= src_io->text;
480 if (!cp || !*cp) return -1;
482 if (*cp == ';' || *cp == '\n') cp++;
483 l= strcspn(cp,";\n");
487 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
497 static void readconfiggeneric(adns_state ads, const char *filename,
498 int (*getline)(adns_state ads, getline_ctx*,
499 const char *filename, int lno,
500 char *buf, int buflen),
501 /* Returns >=0 for success, -1 for EOF or error
502 * (error will have been reported), or -2 for
503 * bad line was encountered, try again.
505 getline_ctx gl_ctx) {
506 char linebuf[2000], *p, *q;
508 const struct configcommandinfo *ccip;
511 (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
513 if (l == -2) continue;
514 while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
517 while (ctype_whitespace(*p)) p++;
518 if (*p == '#' || *p == ';' || !*p) continue;
520 while (*q && !ctype_whitespace(*q)) q++;
522 for (ccip=configcommandinfos;
524 !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
527 if (ads->config_report_unknown)
528 adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
529 filename,lno,(int)(q-p),p);
532 while (ctype_whitespace(*q)) q++;
533 ccip->fn(ads,filename,lno,q);
537 static const char *instrum_getenv(adns_state ads, const char *envvar) {
540 value= getenv(envvar);
541 if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
542 else adns__debug(ads,-1,0,"environment variable %s"
543 " set to `%s'",envvar,value);
547 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
550 gl_ctx.file= fopen(filename,"r");
552 if (errno == ENOENT) {
554 adns__debug(ads,-1,0, "configuration file"
555 " `%s' does not exist",filename);
559 adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
560 filename,strerror(errno));
564 readconfiggeneric(ads,filename,gl_file,gl_ctx);
569 static void readconfigtext(adns_state ads, const char *text,
570 const char *showname) {
574 readconfiggeneric(ads,showname,gl_text,gl_ctx);
577 static void readconfigenv(adns_state ads, const char *envvar) {
578 const char *filename;
580 if (ads->iflags & adns_if_noenv) {
581 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
584 filename= instrum_getenv(ads,envvar);
585 if (filename) readconfig(ads,filename,1);
588 static void readconfigenvtext(adns_state ads, const char *envvar) {
589 const char *textdata;
591 if (ads->iflags & adns_if_noenv) {
592 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
595 textdata= instrum_getenv(ads,envvar);
596 if (textdata) readconfigtext(ads,textdata,envvar);
600 int adns__setnonblock(adns_state ads, int fd) {
603 r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
605 r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
609 static int init_begin(adns_state *ads_r, adns_initflags flags,
610 adns_logcallbackfn *logfn, void *logfndata) {
614 if (flags & ~(adns_initflags)(0x4fff))
615 /* 0x4000 is reserved for `harmless' future expansion */
618 ads= malloc(sizeof(*ads)); if (!ads) return errno;
622 ads->logfndata= logfndata;
624 LIST_INIT(ads->udpw);
625 LIST_INIT(ads->tcpw);
626 LIST_INIT(ads->childw);
627 LIST_INIT(ads->output);
628 LIST_INIT(ads->intdone);
633 adns__vbuf_init(&ads->tcpsend);
634 adns__vbuf_init(&ads->tcprecv);
635 ads->tcprecv_skip= 0;
636 ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
638 ads->tcpstate= server_disconnected;
639 timerclear(&ads->tcptimeout);
641 ads->config_report_unknown=1;
644 ads->rand48xsubi[0]= pid;
645 ads->rand48xsubi[1]= (unsigned long)pid >> 16;
646 ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
652 static int init_finish(adns_state ads) {
653 struct sockaddr_in sin;
654 struct protoent *proto;
655 struct udpsocket *udp;
659 if (!ads->nservers) {
660 if (ads->logfn && ads->iflags & adns_if_debug)
661 adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
662 memset(&sin, 0, sizeof(sin));
663 sin.sin_family = AF_INET;
664 sin.sin_port = htons(DNS_PORT);
665 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
666 addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
669 proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
671 for (i=0; i<ads->nservers; i++) {
672 if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
674 assert(ads->nudpsockets < MAXUDP);
675 udp= &ads->udpsockets[ads->nudpsockets];
676 udp->af= ads->servers[i].addr.sa.sa_family;
677 udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
678 if (udp->fd < 0) { r= errno; goto x_free; }
680 r= adns__setnonblock(ads,udp->fd);
681 if (r) { r= errno; goto x_closeudp; }
687 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
693 static void init_abort(adns_state ads) {
694 if (ads->nsearchlist) {
695 free(ads->searchlist[0]);
696 free(ads->searchlist);
701 static void logfn_file(adns_state ads, void *logfndata,
702 const char *fmt, va_list al) {
703 vfprintf(logfndata,fmt,al);
706 static int init_files(adns_state *ads_r, adns_initflags flags,
707 adns_logcallbackfn *logfn, void *logfndata) {
709 const char *res_options, *adns_res_options;
712 r= init_begin(&ads, flags, logfn, logfndata);
715 res_options= instrum_getenv(ads,"RES_OPTIONS");
716 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
717 ccf_options(ads,"RES_OPTIONS",-1,res_options);
718 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
720 readconfig(ads,"/etc/resolv.conf",1);
721 readconfig(ads,"/etc/resolv-adns.conf",0);
722 readconfigenv(ads,"RES_CONF");
723 readconfigenv(ads,"ADNS_RES_CONF");
725 readconfigenvtext(ads,"RES_CONF_TEXT");
726 readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
728 ccf_options(ads,"RES_OPTIONS",-1,res_options);
729 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
731 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
732 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
734 if (ads->configerrno && ads->configerrno != EINVAL) {
743 adns__consistency(ads,0,cc_exit);
748 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
749 return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
752 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
753 adns_logcallbackfn *logfn, void *logfndata,
754 const char *configtext) {
758 r= init_begin(&ads, flags, logfn, logfndata);
761 readconfigtext(ads,configtext,"<supplied configuration text>");
762 if (ads->configerrno) {
768 r= init_finish(ads); if (r) return r;
769 adns__consistency(ads,0,cc_exit);
774 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
775 FILE *diagfile, const char *configtext) {
776 return init_strcfg(ads_r, flags,
777 diagfile ? logfn_file : 0, diagfile,
781 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
782 const char *configtext /*0=>use default config files*/,
783 adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
784 void *logfndata /*0 with logfn==0 => discard*/) {
785 if (!logfn && logfndata)
788 return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
790 return init_files(newstate_r, flags, logfn, logfndata);
793 static void cancel_all(adns_query qu) {
794 if (!qu->parent) adns__cancel(qu);
795 else cancel_all(qu->parent);
798 void adns_finish(adns_state ads) {
800 adns__consistency(ads,0,cc_enter);
802 if (ads->udpw.head) cancel_all(ads->udpw.head);
803 else if (ads->tcpw.head) cancel_all(ads->tcpw.head);
804 else if (ads->childw.head) cancel_all(ads->childw.head);
805 else if (ads->output.head) cancel_all(ads->output.head);
806 else if (ads->intdone.head) cancel_all(ads->output.head);
809 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
810 if (ads->tcpsocket >= 0) close(ads->tcpsocket);
811 adns__vbuf_free(&ads->tcpsend);
812 adns__vbuf_free(&ads->tcprecv);
817 void adns_forallqueries_begin(adns_state ads) {
818 adns__consistency(ads,0,cc_enter);
820 ads->udpw.head ? ads->udpw.head :
821 ads->tcpw.head ? ads->tcpw.head :
822 ads->childw.head ? ads->childw.head :
826 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
829 adns__consistency(ads,0,cc_enter);
830 nqu= ads->forallnext;
836 } else if (qu == ads->udpw.tail) {
838 ads->tcpw.head ? ads->tcpw.head :
839 ads->childw.head ? ads->childw.head :
841 } else if (qu == ads->tcpw.tail) {
843 ads->childw.head ? ads->childw.head :
845 } else if (qu == ads->childw.tail) {
846 nqu= ads->output.head;
850 if (!qu->parent) break;
852 ads->forallnext= nqu;
853 if (context_r) *context_r= qu->ctx.ext;