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];
117 a.len= sizeof(a.addr);
118 err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&a.len);
123 configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
126 configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
130 adns__debug(ads,-1,0,"using nameserver %s",
131 adns__sockaddr_ntoa(&a.addr.sa, addrbuf));
132 addserver(ads,&a.addr.sa,a.len);
135 static void ccf_search(adns_state ads, const char *fn,
136 int lno, const char *buf) {
137 const char *bufp, *word;
138 char *newchars, **newptrs, **pp;
146 while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
148 newptrs= malloc(sizeof(char*)*count);
149 if (!newptrs) { saveerr(ads,errno); return; }
151 newchars= malloc(tl);
152 if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
156 while (nextword(&bufp,&word,&l)) {
158 memcpy(newchars,word,l);
164 ads->nsearchlist= count;
165 ads->searchlist= newptrs;
168 static int gen_pton(const char *text, int want_af, adns_sockaddr *a) {
173 err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
175 if (err) { assert(err == EINVAL); return 0; }
176 if (want_af != AF_UNSPEC && a->sa.sa_family != want_af) return 0;
180 static void ccf_sortlist(adns_state ads, const char *fn,
181 int lno, const char *buf) {
183 char tbuf[200], *slash, *ep;
184 const char *maskwhat;
192 while (nextword(&buf,&word,&l)) {
193 if (ads->nsortlist >= MAXSORTLIST) {
194 adns__diag(ads,-1,0,"too many sortlist entries,"
195 " ignoring %.*s onwards",l,word);
199 if (l >= sizeof(tbuf)) {
200 configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
204 memcpy(tbuf,word,l); tbuf[l]= 0;
205 slash= strchr(tbuf,'/');
206 if (slash) *slash++= 0;
208 sl= &ads->sortlist[ads->nsortlist];
209 if (!gen_pton(tbuf, AF_UNSPEC, &sl->base)) {
210 configparseerr(ads,fn,lno,"invalid address `%s' in sortlist",tbuf);
215 if (slash[strspn(slash, "0123456789")]) {
217 if (!gen_pton(slash, sl->base.sa.sa_family, &sl->mask)) {
218 configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
222 maskwhat = "prefix length";
223 initial= strtoul(slash,&ep,10);
224 if (*ep || initial>adns__addr_width(sl->base.sa.sa_family)) {
225 configparseerr(ads,fn,lno,"mask length `%s' invalid",slash);
228 sl->mask.sa.sa_family= sl->base.sa.sa_family;
229 adns__prefix_mask(&sl->mask, initial);
232 maskwhat = "implied prefix length";
233 initial= adns__guess_prefix_length(&sl->base);
235 configparseerr(ads,fn,lno, "network address `%s'"
236 " in sortlist is not in classed ranges,"
237 " must specify mask explicitly", tbuf);
240 sl->mask.sa.sa_family= sl->base.sa.sa_family;
241 adns__prefix_mask(&sl->mask, initial);
244 if (!adns__addr_matches(sl->base.sa.sa_family,
245 adns__sockaddr_addr(&sl->base.sa),
246 &sl->base,&sl->mask)) {
248 configparseerr(ads,fn,lno, "%s %d in sortlist"
249 " overlaps address `%s'",maskwhat,initial,tbuf);
251 configparseerr(ads,fn,lno, "%s `%s' in sortlist"
252 " overlaps address `%s'",maskwhat,slash,tbuf);
261 static void ccf_options(adns_state ads, const char *fn,
262 int lno, const char *buf) {
263 const char *word, *rhs;
270 #define OPTION__IS(s,op) (l op (sizeof(s)-1) && !memcmp(word,s,(sizeof(s)-1)))
271 #define OPTION_IS(s) (OPTION__IS(s,==))
272 #define OPTION_STARTS(s) (OPTION__IS(s,>=) ? ((rhs=word+sizeof(s)-1)) : 0)
274 while (nextword(&buf,&word,&l)) {
275 if (OPTION_IS("debug")) {
276 ads->iflags |= adns_if_debug;
279 if (OPTION_STARTS("ndots:")) {
280 v= strtoul(rhs,&ep,10);
281 if (ep==rhs || ep != word+l || v > INT_MAX) {
282 configparseerr(ads,fn,lno,"option `%.*s' malformed"
283 " or has bad value",l,word);
289 if (OPTION_STARTS("adns_checkc:")) {
290 if (!strcmp(rhs,"none")) {
291 ads->iflags &= ~adns_if_checkc_freq;
292 ads->iflags |= adns_if_checkc_entex;
293 } else if (!strcmp(rhs,"entex")) {
294 ads->iflags &= ~adns_if_checkc_freq;
295 ads->iflags |= adns_if_checkc_entex;
296 } else if (!strcmp(rhs,"freq")) {
297 ads->iflags |= adns_if_checkc_freq;
299 configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
300 "(must be none, entex or freq", rhs);
304 if (OPTION_STARTS("adns_af:")) {
306 ads->iflags &= ~adns_if_afmask;
307 if (strcmp(word,"any")) for (;;) {
308 i= strcspn(word,",");
309 if (i>=4 && !memcmp(word,"ipv4",4))
310 ads->iflags |= adns_if_permit_ipv4;
311 else if (i>=4 && !memcmp(word,"ipv6",4))
312 ads->iflags |= adns_if_permit_ipv6;
314 configparseerr(ads,fn,lno, "option adns_af has bad value `%.*s' "
315 "(must be `any' or list {`ipv4',`ipv6'},...)",
324 adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
332 static void ccf_clearnss(adns_state ads, const char *fn,
333 int lno, const char *buf) {
337 static void ccf_include(adns_state ads, const char *fn,
338 int lno, const char *buf) {
340 configparseerr(ads,fn,lno,"`include' directive with no filename");
343 readconfig(ads,buf,1);
346 static void ccf_lookup(adns_state ads, const char *fn, int lno,
353 configparseerr(ads,fn,lno,"`lookup' directive with no databases");
357 while (nextword(&buf,&word,&l)) {
358 if (l==4 && !memcmp(word,"bind",4)) {
360 } else if (l==4 && !memcmp(word,"file",4)) {
361 /* ignore this and hope /etc/hosts is not essential */
362 } else if (l==2 && !memcmp(word,"yp",2)) {
363 adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
366 adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
372 adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
375 static const struct configcommandinfo {
377 void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
378 } configcommandinfos[]= {
379 { "nameserver", ccf_nameserver },
380 { "domain", ccf_search },
381 { "search", ccf_search },
382 { "sortlist", ccf_sortlist },
383 { "options", ccf_options },
384 { "clearnameservers", ccf_clearnss },
385 { "include", ccf_include },
386 { "lookup", ccf_lookup }, /* OpenBSD */
395 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
396 int lno, char *buf, int buflen) {
397 FILE *file= src_io->file;
405 for (;;) { /* loop over chars */
407 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
412 adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
414 } else if (c == '\n') {
416 } else if (c == EOF) {
419 adns__diag(ads,-1,0,"%s:%d: read error: %s",
420 filename,lno,strerror(errno));
436 while ((c= getc(file)) != EOF && c != '\n');
440 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
441 int lno, char *buf, int buflen) {
442 const char *cp= src_io->text;
445 if (!cp || !*cp) return -1;
447 if (*cp == ';' || *cp == '\n') cp++;
448 l= strcspn(cp,";\n");
452 adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
462 static void readconfiggeneric(adns_state ads, const char *filename,
463 int (*getline)(adns_state ads, getline_ctx*,
464 const char *filename, int lno,
465 char *buf, int buflen),
466 /* Returns >=0 for success, -1 for EOF or error
467 * (error will have been reported), or -2 for
468 * bad line was encountered, try again.
470 getline_ctx gl_ctx) {
471 char linebuf[2000], *p, *q;
473 const struct configcommandinfo *ccip;
476 (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
478 if (l == -2) continue;
479 while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
482 while (ctype_whitespace(*p)) p++;
483 if (*p == '#' || *p == ';' || !*p) continue;
485 while (*q && !ctype_whitespace(*q)) q++;
487 for (ccip=configcommandinfos;
489 !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
492 adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
493 filename,lno,(int)(q-p),p);
496 while (ctype_whitespace(*q)) q++;
497 ccip->fn(ads,filename,lno,q);
501 static const char *instrum_getenv(adns_state ads, const char *envvar) {
504 value= getenv(envvar);
505 if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
506 else adns__debug(ads,-1,0,"environment variable %s"
507 " set to `%s'",envvar,value);
511 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
514 gl_ctx.file= fopen(filename,"r");
516 if (errno == ENOENT) {
518 adns__debug(ads,-1,0, "configuration file"
519 " `%s' does not exist",filename);
523 adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
524 filename,strerror(errno));
528 readconfiggeneric(ads,filename,gl_file,gl_ctx);
533 static void readconfigtext(adns_state ads, const char *text,
534 const char *showname) {
538 readconfiggeneric(ads,showname,gl_text,gl_ctx);
541 static void readconfigenv(adns_state ads, const char *envvar) {
542 const char *filename;
544 if (ads->iflags & adns_if_noenv) {
545 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
548 filename= instrum_getenv(ads,envvar);
549 if (filename) readconfig(ads,filename,1);
552 static void readconfigenvtext(adns_state ads, const char *envvar) {
553 const char *textdata;
555 if (ads->iflags & adns_if_noenv) {
556 adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
559 textdata= instrum_getenv(ads,envvar);
560 if (textdata) readconfigtext(ads,textdata,envvar);
564 int adns__setnonblock(adns_state ads, int fd) {
567 r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
569 r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
573 static int init_begin(adns_state *ads_r, adns_initflags flags,
574 adns_logcallbackfn *logfn, void *logfndata) {
578 if (flags & ~(adns_initflags)(0x4fff))
579 /* 0x4000 is reserved for `harmless' future expansion */
582 ads= malloc(sizeof(*ads)); if (!ads) return errno;
586 ads->logfndata= logfndata;
588 LIST_INIT(ads->udpw);
589 LIST_INIT(ads->tcpw);
590 LIST_INIT(ads->childw);
591 LIST_INIT(ads->output);
592 LIST_INIT(ads->intdone);
597 adns__vbuf_init(&ads->tcpsend);
598 adns__vbuf_init(&ads->tcprecv);
599 ads->tcprecv_skip= 0;
600 ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
602 ads->tcpstate= server_disconnected;
603 timerclear(&ads->tcptimeout);
607 ads->rand48xsubi[0]= pid;
608 ads->rand48xsubi[1]= (unsigned long)pid >> 16;
609 ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
615 static int init_finish(adns_state ads) {
616 struct sockaddr_in sin;
617 struct protoent *proto;
618 struct udpsocket *udp;
622 if (!ads->nservers) {
623 if (ads->logfn && ads->iflags & adns_if_debug)
624 adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
625 memset(&sin, 0, sizeof(sin));
626 sin.sin_family = AF_INET;
627 sin.sin_port = htons(DNS_PORT);
628 sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
629 addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
632 proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
634 for (i=0; i<ads->nservers; i++) {
635 if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
637 assert(ads->nudpsockets < MAXUDP);
638 udp= &ads->udpsockets[ads->nudpsockets];
639 udp->af= ads->servers[i].addr.sa.sa_family;
640 udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
641 if (udp->fd < 0) { r= errno; goto x_free; }
643 r= adns__setnonblock(ads,udp->fd);
644 if (r) { r= errno; goto x_closeudp; }
650 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
656 static void init_abort(adns_state ads) {
657 if (ads->nsearchlist) {
658 free(ads->searchlist[0]);
659 free(ads->searchlist);
664 static void logfn_file(adns_state ads, void *logfndata,
665 const char *fmt, va_list al) {
666 vfprintf(logfndata,fmt,al);
669 static int init_files(adns_state *ads_r, adns_initflags flags,
670 adns_logcallbackfn *logfn, void *logfndata) {
672 const char *res_options, *adns_res_options;
675 r= init_begin(&ads, flags, logfn, logfndata);
678 res_options= instrum_getenv(ads,"RES_OPTIONS");
679 adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
680 ccf_options(ads,"RES_OPTIONS",-1,res_options);
681 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
683 readconfig(ads,"/etc/resolv.conf",1);
684 readconfig(ads,"/etc/resolv-adns.conf",0);
685 readconfigenv(ads,"RES_CONF");
686 readconfigenv(ads,"ADNS_RES_CONF");
688 readconfigenvtext(ads,"RES_CONF_TEXT");
689 readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
691 ccf_options(ads,"RES_OPTIONS",-1,res_options);
692 ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
694 ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
695 ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
697 if (ads->configerrno && ads->configerrno != EINVAL) {
706 adns__consistency(ads,0,cc_entex);
711 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
712 return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
715 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
716 adns_logcallbackfn *logfn, void *logfndata,
717 const char *configtext) {
721 r= init_begin(&ads, flags, logfn, logfndata);
724 readconfigtext(ads,configtext,"<supplied configuration text>");
725 if (ads->configerrno) {
731 r= init_finish(ads); if (r) return r;
732 adns__consistency(ads,0,cc_entex);
737 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
738 FILE *diagfile, const char *configtext) {
739 return init_strcfg(ads_r, flags,
740 diagfile ? logfn_file : 0, diagfile,
744 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
745 const char *configtext /*0=>use default config files*/,
746 adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
747 void *logfndata /*0 with logfn==0 => discard*/) {
748 if (!logfn && logfndata)
751 return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
753 return init_files(newstate_r, flags, logfn, logfndata);
756 void adns_finish(adns_state ads) {
758 adns__consistency(ads,0,cc_entex);
760 if (ads->udpw.head) adns__cancel(ads->udpw.head);
761 else if (ads->tcpw.head) adns__cancel(ads->tcpw.head);
762 else if (ads->childw.head) adns__cancel(ads->childw.head);
763 else if (ads->output.head) adns__cancel(ads->output.head);
764 else if (ads->intdone.head) adns__cancel(ads->output.head);
767 for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
768 if (ads->tcpsocket >= 0) close(ads->tcpsocket);
769 adns__vbuf_free(&ads->tcpsend);
770 adns__vbuf_free(&ads->tcprecv);
775 void adns_forallqueries_begin(adns_state ads) {
776 adns__consistency(ads,0,cc_entex);
778 ads->udpw.head ? ads->udpw.head :
779 ads->tcpw.head ? ads->tcpw.head :
780 ads->childw.head ? ads->childw.head :
784 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
787 adns__consistency(ads,0,cc_entex);
788 nqu= ads->forallnext;
794 } else if (qu == ads->udpw.tail) {
796 ads->tcpw.head ? ads->tcpw.head :
797 ads->childw.head ? ads->childw.head :
799 } else if (qu == ads->tcpw.tail) {
801 ads->childw.head ? ads->childw.head :
803 } else if (qu == ads->childw.tail) {
804 nqu= ads->output.head;
808 if (!qu->parent) break;
810 ads->forallnext= nqu;
811 if (context_r) *context_r= qu->ctx.ext;