mdw@git.distorted.org.uk Git - adns/blob - src/setup.c

   1 /*
   2  * setup.c
   3  * - configuration file parsing
   4  * - management of global state
   5  */
   6 /*
   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.)
  13  *
  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)
  17  *  any later version.
  18  *
  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.
  23  *
  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.
  26  */
  27
  28 #include <stdlib.h>
  29 #include <errno.h>
  30 #include <limits.h>
  31 #include <unistd.h>
  32 #include <fcntl.h>
  33
  34 #include <sys/types.h>
  35 #include <netdb.h>
  36 #include <sys/socket.h>
  37 #include <netinet/in.h>
  38 #include <arpa/inet.h>
  39
  40 #include "internal.h"
  41
  42 static void readconfig(adns_state ads, const char *filename, int warnmissing);
  43
  44 static void addserver(adns_state ads, const struct sockaddr *sa, int salen) {
  45   int i;
  46   adns_rr_addr *ss;
  47   char buf[ADNS_ADDR2TEXT_BUFLEN];
  48
  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));
  53       return;
  54     }
  55   }
  56
  57   if (ads->nservers>=MAXSERVERS) {
  58     adns__diag(ads,-1,0,"too many nameservers, ignoring %s",
  59                adns__sockaddr_ntoa(sa, buf));
  60     return;
  61   }
  62
  63   ss= ads->servers+ads->nservers;
  64   assert(salen <= sizeof(ss->addr));
  65   ss->len = salen;
  66   memcpy(&ss->addr, sa, salen);
  67   ads->nservers++;
  68 }
  69
  70 static void freesearchlist(adns_state ads) {
  71   if (ads->nsearchlist) free(*ads->searchlist);
  72   free(ads->searchlist);
  73 }
  74
  75 static void saveerr(adns_state ads, int en) {
  76   if (!ads->configerrno) ads->configerrno= en;
  77 }
  78
  79 static void configparseerr(adns_state ads, const char *fn, int lno,
  80                            const char *fmt, ...) {
  81   va_list al;
  82
  83   saveerr(ads,EINVAL);
  84   if (!ads->logfn || (ads->iflags & adns_if_noerrprint)) return;
  85
  86   if (lno==-1) adns__lprintf(ads,"adns: %s: ",fn);
  87   else adns__lprintf(ads,"adns: %s:%d: ",fn,lno);
  88   va_start(al,fmt);
  89   adns__vlprintf(ads,fmt,al);
  90   va_end(al);
  91   adns__lprintf(ads,"\n");
  92 }
  93
  94 static int nextword(const char **bufp_io, const char **word_r, int *l_r) {
  95   const char *p, *q;
  96
  97   p= *bufp_io;
  98   while (ctype_whitespace(*p)) p++;
  99   if (!*p) return 0;
 100
 101   q= p;
 102   while (*q && !ctype_whitespace(*q)) q++;
 103
 104   *l_r= q-p;
 105   *word_r= p;
 106   *bufp_io= q;
 107
 108   return 1;
 109 }
 110
 111 static void ccf_nameserver(adns_state ads, const char *fn,
 112                            int lno, const char *buf) {
 113   adns_rr_addr a;
 114   char addrbuf[ADNS_ADDR2TEXT_BUFLEN];
 115   int err;
 116
 117   a.len= sizeof(a.addr);
 118   err= adns_text2addr(buf,DNS_PORT, 0, &a.addr.sa,&a.len);
 119   switch (err) {
 120   case 0:
 121     break;
 122   case EINVAL:
 123     configparseerr(ads,fn,lno,"invalid nameserver address `%s'",buf);
 124     return;
 125   default:
 126     configparseerr(ads,fn,lno,"failed to parse nameserver address `%s': %s",
 127                    buf,strerror(err));
 128     return;
 129   }
 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);
 133 }
 134
 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;
 139   int count, tl, l;
 140
 141   if (!buf) return;
 142
 143   bufp= buf;
 144   count= 0;
 145   tl= 0;
 146   while (nextword(&bufp,&word,&l)) { count++; tl += l+1; }
 147
 148   newptrs= malloc(sizeof(char*)*count);
 149   if (!newptrs) { saveerr(ads,errno); return; }
 150
 151   newchars= malloc(tl);
 152   if (!newchars) { saveerr(ads,errno); free(newptrs); return; }
 153
 154   bufp= buf;
 155   pp= newptrs;
 156   while (nextword(&bufp,&word,&l)) {
 157     *pp++= newchars;
 158     memcpy(newchars,word,l);
 159     newchars += l;
 160     *newchars++ = 0;
 161   }
 162
 163   freesearchlist(ads);
 164   ads->nsearchlist= count;
 165   ads->searchlist= newptrs;
 166 }
 167
 168 static int gen_pton(const char *text, int want_af, adns_sockaddr *a) {
 169   int err;
 170   int len;
 171
 172   len= sizeof(*a);
 173   err= adns_text2addr(text,0, adns_qf_addrlit_scope_forbid,
 174                       &a->sa, &len);
 175   if (err) { assert(err == EINVAL); return 0; }
 176   if (want_af != AF_UNSPEC && a->sa.sa_family != want_af) return 0;
 177   return 1;
 178 }
 179
 180 static void ccf_sortlist(adns_state ads, const char *fn,
 181                          int lno, const char *buf) {
 182   const char *word;
 183   char tbuf[200], *slash, *ep;
 184   const char *maskwhat;
 185   struct sortlist *sl;
 186   int l;
 187   int initial= -1;
 188
 189   if (!buf) return;
 190
 191   ads->nsortlist= 0;
 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);
 196       return;
 197     }
 198
 199     if (l >= sizeof(tbuf)) {
 200       configparseerr(ads,fn,lno,"sortlist entry `%.*s' too long",l,word);
 201       continue;
 202     }
 203
 204     memcpy(tbuf,word,l); tbuf[l]= 0;
 205     slash= strchr(tbuf,'/');
 206     if (slash) *slash++= 0;
 207
 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);
 211       continue;
 212     }
 213
 214     if (slash) {
 215       if (slash[strspn(slash, "0123456789")]) {
 216         maskwhat = "mask";
 217         if (!gen_pton(slash, sl->base.sa.sa_family, &sl->mask)) {
 218           configparseerr(ads,fn,lno,"invalid mask `%s' in sortlist",slash);
 219           continue;
 220         }
 221       } else {
 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);
 226           continue;
 227         }
 228         sl->mask.sa.sa_family= sl->base.sa.sa_family;
 229         adns__prefix_mask(&sl->mask, initial);
 230       }
 231     } else {
 232       maskwhat = "implied prefix length";
 233       initial= adns__guess_prefix_length(&sl->base);
 234       if (initial < 0) {
 235         configparseerr(ads,fn,lno, "network address `%s'"
 236                        " in sortlist is not in classed ranges,"
 237                        " must specify mask explicitly", tbuf);
 238         continue;
 239       }
 240       sl->mask.sa.sa_family= sl->base.sa.sa_family;
 241       adns__prefix_mask(&sl->mask, initial);
 242     }
 243
 244     if (!adns__addr_matches(sl->base.sa.sa_family,
 245                             adns__sockaddr_addr(&sl->base.sa),
 246                             &sl->base,&sl->mask)) {
 247       if (initial >= 0) {
 248         configparseerr(ads,fn,lno, "%s %d in sortlist"
 249                        " overlaps address `%s'",maskwhat,initial,tbuf);
 250       } else {
 251         configparseerr(ads,fn,lno, "%s `%s' in sortlist"
 252                        " overlaps address `%s'",maskwhat,slash,tbuf);
 253       }
 254       continue;
 255     }
 256
 257     ads->nsortlist++;
 258   }
 259 }
 260
 261 static void ccf_options(adns_state ads, const char *fn,
 262                         int lno, const char *buf) {
 263   const char *opt, *word, *endword, *endopt;
 264   char *ep;
 265   unsigned long v;
 266   int l;
 267
 268   if (!buf) return;
 269
 270 #define WORD__IS(s,op) ((endword-word) op (sizeof(s)-1) && \
 271                           !memcmp(word,s,(sizeof(s)-1)))
 272 #define WORD_IS(s)     (WORD__IS(s,==))
 273 #define WORD_STARTS(s) (WORD__IS(s,>=) ? ((word+=sizeof(s)-1)) : 0)
 274
 275   while (nextword(&buf,&word,&l)) {
 276     opt=word;
 277     endopt=endword=word+l;
 278     if (WORD_IS("debug")) {
 279       ads->iflags |= adns_if_debug;
 280       continue;
 281     }
 282     if (WORD_STARTS("ndots:")) {
 283       v= strtoul(word,&ep,10);
 284       if (ep==word || ep != endword || v > INT_MAX) {
 285         configparseerr(ads,fn,lno,"option `%.*s' malformed"
 286                        " or has bad value",l,opt);
 287         continue;
 288       }
 289       ads->searchndots= v;
 290       continue;
 291     }
 292     if (WORD_STARTS("adns_checkc:")) {
 293       if (WORD_IS("none")) {
 294         ads->iflags &= ~adns_if_checkc_freq;
 295         ads->iflags |= adns_if_checkc_entex;
 296       } else if (WORD_IS("entex")) {
 297         ads->iflags &= ~adns_if_checkc_freq;
 298         ads->iflags |= adns_if_checkc_entex;
 299       } else if (WORD_IS("freq")) {
 300         ads->iflags |= adns_if_checkc_freq;
 301       } else {
 302         configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
 303                        "(must be none, entex or freq", word);
 304       }
 305       continue;
 306     }
 307     if (WORD_STARTS("adns_af:")) {
 308       ads->iflags &= ~adns_if_afmask;
 309       if (!WORD_IS("any")) for (;;) {
 310         const char *comma= memchr(word,',',endopt-word);
 311         endword=comma?comma:endopt;
 312         if (WORD_IS("ipv4"))
 313           ads->iflags |= adns_if_permit_ipv4;
 314         else if (WORD_IS("ipv6"))
 315           ads->iflags |= adns_if_permit_ipv6;
 316         else {
 317           configparseerr(ads,fn,lno, "option adns_af has bad value `%.*s' "
 318                          "(must be `any' or list {`ipv4',`ipv6'},...)",
 319                          (int)(endword-word), word);
 320           break;
 321         }
 322         if (!comma) break;
 323         word= comma+1;
 324       }
 325       continue;
 326     }
 327     if (WORD_IS("adns_ignoreunkcfg")) {
 328       ads->config_report_unknown=0;
 329       continue;
 330     }
 331     if (/* adns's query strategy is not configurable */
 332         WORD_STARTS("timeout:") ||
 333         WORD_STARTS("attempts:") ||
 334         WORD_IS("rotate") ||
 335         /* adns provides the application with knob for this */
 336         WORD_IS("no-check-names") ||
 337         /* adns normally does IPv6 if the application wants it; control
 338          * this with the adns_af: option if you like */
 339         WORD_IS("inet6") ||
 340         /* adns does not do edns0 and this is not a problem */
 341         WORD_IS("edns0"))
 342       continue;
 343     if (ads->config_report_unknown)
 344       adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,opt);
 345   }
 346
 347 #undef WORD__IS
 348 #undef WORD_IS
 349 #undef WORD_STARTS
 350 }
 351
 352 static void ccf_clearnss(adns_state ads, const char *fn,
 353                          int lno, const char *buf) {
 354   ads->nservers= 0;
 355 }
 356
 357 static void ccf_include(adns_state ads, const char *fn,
 358                         int lno, const char *buf) {
 359   if (!*buf) {
 360     configparseerr(ads,fn,lno,"`include' directive with no filename");
 361     return;
 362   }
 363   readconfig(ads,buf,1);
 364 }
 365
 366 static void ccf_lookup(adns_state ads, const char *fn, int lno,
 367                        const char *buf) {
 368   int found_bind=0;
 369   const char *word;
 370   int l;
 371
 372   if (!*buf) {
 373     configparseerr(ads,fn,lno,"`lookup' directive with no databases");
 374     return;
 375   }
 376
 377   while (nextword(&buf,&word,&l)) {
 378     if (l==4 && !memcmp(word,"bind",4)) {
 379       found_bind=1;
 380     } else if (l==4 && !memcmp(word,"file",4)) {
 381       /* ignore this and hope /etc/hosts is not essential */
 382     } else if (l==2 && !memcmp(word,"yp",2)) {
 383       adns__diag(ads,-1,0,"%s:%d: yp lookups not supported by adns", fn,lno);
 384       found_bind=-1;
 385     } else {
 386       if (ads->config_report_unknown)
 387         adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
 388                    fn,lno, l,word);
 389       found_bind=-1;
 390     }
 391   }
 392   if (!found_bind)
 393     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 394 }
 395
 396 static void ccf_ignore(adns_state ads, const char *fn, int lno,
 397                        const char *buf) {
 398 }
 399
 400 static const struct configcommandinfo {
 401   const char *name;
 402   void (*fn)(adns_state ads, const char *fn, int lno, const char *buf);
 403 } configcommandinfos[]= {
 404   { "nameserver",        ccf_nameserver  },
 405   { "domain",            ccf_search      },
 406   { "search",            ccf_search      },
 407   { "sortlist",          ccf_sortlist    },
 408   { "options",           ccf_options     },
 409   { "clearnameservers",  ccf_clearnss    },
 410   { "include",           ccf_include     },
 411   { "lookup",            ccf_lookup      }, /* OpenBSD */
 412   { "lwserver",          ccf_ignore      }, /* BIND9 lwresd */
 413   {  0                                   }
 414 };
 415
 416 typedef union {
 417   FILE *file;
 418   const char *text;
 419 } getline_ctx;
 420
 421 static int gl_file(adns_state ads, getline_ctx *src_io, const char *filename,
 422                    int lno, char *buf, int buflen) {
 423   FILE *file= src_io->file;
 424   int c, i;
 425   char *p;
 426
 427   p= buf;
 428   buflen--;
 429   i= 0;
 430
 431   for (;;) { /* loop over chars */
 432     if (i == buflen) {
 433       adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 434       goto x_badline;
 435     }
 436     c= getc(file);
 437     if (!c) {
 438       adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
 439       goto x_badline;
 440     } else if (c == '\n') {
 441       break;
 442     } else if (c == EOF) {
 443       if (ferror(file)) {
 444         saveerr(ads,errno);
 445         adns__diag(ads,-1,0,"%s:%d: read error: %s",
 446                    filename,lno,strerror(errno));
 447         return -1;
 448       }
 449       if (!i) return -1;
 450       break;
 451     } else {
 452       *p++= c;
 453       i++;
 454     }
 455   }
 456
 457   *p++= 0;
 458   return i;
 459
 460  x_badline:
 461   saveerr(ads,EINVAL);
 462   while ((c= getc(file)) != EOF && c != '\n');
 463   return -2;
 464 }
 465
 466 static int gl_text(adns_state ads, getline_ctx *src_io, const char *filename,
 467                    int lno, char *buf, int buflen) {
 468   const char *cp= src_io->text;
 469   int l;
 470
 471   if (!cp || !*cp) return -1;
 472
 473   if (*cp == ';' || *cp == '\n') cp++;
 474   l= strcspn(cp,";\n");
 475   src_io->text = cp+l;
 476
 477   if (l >= buflen) {
 478     adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 479     saveerr(ads,EINVAL);
 480     return -2;
 481   }
 482
 483   memcpy(buf,cp,l);
 484   buf[l]= 0;
 485   return l;
 486 }
 487
 488 static void readconfiggeneric(adns_state ads, const char *filename,
 489                               int (*getline)(adns_state ads, getline_ctx*,
 490                                              const char *filename, int lno,
 491                                              char *buf, int buflen),
 492                               /* Returns >=0 for success, -1 for EOF or error
 493                                * (error will have been reported), or -2 for
 494                                * bad line was encountered, try again.
 495                                */
 496                               getline_ctx gl_ctx) {
 497   char linebuf[2000], *p, *q;
 498   int lno, l, dirl;
 499   const struct configcommandinfo *ccip;
 500
 501   for (lno=1;
 502        (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
 503        lno++) {
 504     if (l == -2) continue;
 505     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 506     linebuf[l]= 0;
 507     p= linebuf;
 508     while (ctype_whitespace(*p)) p++;
 509     if (*p == '#' || *p == ';' || !*p) continue;
 510     q= p;
 511     while (*q && !ctype_whitespace(*q)) q++;
 512     dirl= q-p;
 513     for (ccip=configcommandinfos;
 514          ccip->name &&
 515            !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
 516          ccip++);
 517     if (!ccip->name) {
 518       if (ads->config_report_unknown)
 519         adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
 520                    filename,lno,(int)(q-p),p);
 521       continue;
 522     }
 523     while (ctype_whitespace(*q)) q++;
 524     ccip->fn(ads,filename,lno,q);
 525   }
 526 }
 527
 528 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 529   const char *value;
 530
 531   value= getenv(envvar);
 532   if (!value) adns__debug(ads,-1,0,"environment variable %s not set",envvar);
 533   else adns__debug(ads,-1,0,"environment variable %s"
 534                    " set to `%s'",envvar,value);
 535   return value;
 536 }
 537
 538 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
 539   getline_ctx gl_ctx;
 540
 541   gl_ctx.file= fopen(filename,"r");
 542   if (!gl_ctx.file) {
 543     if (errno == ENOENT) {
 544       if (warnmissing)
 545         adns__debug(ads,-1,0, "configuration file"
 546                     " `%s' does not exist",filename);
 547       return;
 548     }
 549     saveerr(ads,errno);
 550     adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
 551                filename,strerror(errno));
 552     return;
 553   }
 554
 555   readconfiggeneric(ads,filename,gl_file,gl_ctx);
 556
 557   fclose(gl_ctx.file);
 558 }
 559
 560 static void readconfigtext(adns_state ads, const char *text,
 561                            const char *showname) {
 562   getline_ctx gl_ctx;
 563
 564   gl_ctx.text= text;
 565   readconfiggeneric(ads,showname,gl_text,gl_ctx);
 566 }
 567
 568 static void readconfigenv(adns_state ads, const char *envvar) {
 569   const char *filename;
 570
 571   if (ads->iflags & adns_if_noenv) {
 572     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 573     return;
 574   }
 575   filename= instrum_getenv(ads,envvar);
 576   if (filename) readconfig(ads,filename,1);
 577 }
 578
 579 static void readconfigenvtext(adns_state ads, const char *envvar) {
 580   const char *textdata;
 581
 582   if (ads->iflags & adns_if_noenv) {
 583     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 584     return;
 585   }
 586   textdata= instrum_getenv(ads,envvar);
 587   if (textdata) readconfigtext(ads,textdata,envvar);
 588 }
 589
 590
 591 int adns__setnonblock(adns_state ads, int fd) {
 592   int r;
 593
 594   r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
 595   r |= O_NONBLOCK;
 596   r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
 597   return 0;
 598 }
 599
 600 static int init_begin(adns_state *ads_r, adns_initflags flags,
 601                       adns_logcallbackfn *logfn, void *logfndata) {
 602   adns_state ads;
 603   pid_t pid;
 604
 605   if (flags & ~(adns_initflags)(0x4fff))
 606     /* 0x4000 is reserved for `harmless' future expansion */
 607     return ENOSYS;
 608
 609   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 610
 611   ads->iflags= flags;
 612   ads->logfn= logfn;
 613   ads->logfndata= logfndata;
 614   ads->configerrno= 0;
 615   LIST_INIT(ads->udpw);
 616   LIST_INIT(ads->tcpw);
 617   LIST_INIT(ads->childw);
 618   LIST_INIT(ads->output);
 619   LIST_INIT(ads->intdone);
 620   ads->forallnext= 0;
 621   ads->nextid= 0x311f;
 622   ads->nudpsockets= 0;
 623   ads->tcpsocket= -1;
 624   adns__vbuf_init(&ads->tcpsend);
 625   adns__vbuf_init(&ads->tcprecv);
 626   ads->tcprecv_skip= 0;
 627   ads->nservers= ads->nsortlist= ads->nsearchlist= ads->tcpserver= 0;
 628   ads->searchndots= 1;
 629   ads->tcpstate= server_disconnected;
 630   timerclear(&ads->tcptimeout);
 631   ads->searchlist= 0;
 632   ads->config_report_unknown=1;
 633
 634   pid= getpid();
 635   ads->rand48xsubi[0]= pid;
 636   ads->rand48xsubi[1]= (unsigned long)pid >> 16;
 637   ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
 638
 639   *ads_r= ads;
 640   return 0;
 641 }
 642
 643 static int init_finish(adns_state ads) {
 644   struct sockaddr_in sin;
 645   struct protoent *proto;
 646   struct udpsocket *udp;
 647   int i;
 648   int r;
 649
 650   if (!ads->nservers) {
 651     if (ads->logfn && ads->iflags & adns_if_debug)
 652       adns__lprintf(ads,"adns: no nameservers, using IPv4 localhost\n");
 653     memset(&sin, 0, sizeof(sin));
 654     sin.sin_family = AF_INET;
 655     sin.sin_port = htons(DNS_PORT);
 656     sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 657     addserver(ads,(struct sockaddr *)&sin, sizeof(sin));
 658   }
 659
 660   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 661   ads->nudpsockets= 0;
 662   for (i=0; i<ads->nservers; i++) {
 663     if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
 664       continue;
 665     assert(ads->nudpsockets < MAXUDP);
 666     udp= &ads->udpsockets[ads->nudpsockets];
 667     udp->af= ads->servers[i].addr.sa.sa_family;
 668     udp->fd= socket(udp->af,SOCK_DGRAM,proto->p_proto);
 669     if (udp->fd < 0) { r= errno; goto x_free; }
 670     ads->nudpsockets++;
 671     r= adns__setnonblock(ads,udp->fd);
 672     if (r) { r= errno; goto x_closeudp; }
 673   }
 674
 675   return 0;
 676
 677  x_closeudp:
 678   for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
 679  x_free:
 680   free(ads);
 681   return r;
 682 }
 683
 684 static void init_abort(adns_state ads) {
 685   if (ads->nsearchlist) {
 686     free(ads->searchlist[0]);
 687     free(ads->searchlist);
 688   }
 689   free(ads);
 690 }
 691
 692 static void logfn_file(adns_state ads, void *logfndata,
 693                        const char *fmt, va_list al) {
 694   vfprintf(logfndata,fmt,al);
 695 }
 696
 697 static int init_files(adns_state *ads_r, adns_initflags flags,
 698                       adns_logcallbackfn *logfn, void *logfndata) {
 699   adns_state ads;
 700   const char *res_options, *adns_res_options;
 701   int r;
 702
 703   r= init_begin(&ads, flags, logfn, logfndata);
 704   if (r) return r;
 705
 706   res_options= instrum_getenv(ads,"RES_OPTIONS");
 707   adns_res_options= instrum_getenv(ads,"ADNS_RES_OPTIONS");
 708   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 709   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 710
 711   readconfig(ads,"/etc/resolv.conf",1);
 712   readconfig(ads,"/etc/resolv-adns.conf",0);
 713   readconfigenv(ads,"RES_CONF");
 714   readconfigenv(ads,"ADNS_RES_CONF");
 715
 716   readconfigenvtext(ads,"RES_CONF_TEXT");
 717   readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
 718
 719   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 720   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 721
 722   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 723   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 724
 725   if (ads->configerrno && ads->configerrno != EINVAL) {
 726     r= ads->configerrno;
 727     init_abort(ads);
 728     return r;
 729   }
 730
 731   r= init_finish(ads);
 732   if (r) return r;
 733
 734   adns__consistency(ads,0,cc_entex);
 735   *ads_r= ads;
 736   return 0;
 737 }
 738
 739 int adns_init(adns_state *ads_r, adns_initflags flags, FILE *diagfile) {
 740   return init_files(ads_r, flags, logfn_file, diagfile ? diagfile : stderr);
 741 }
 742
 743 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
 744                        adns_logcallbackfn *logfn, void *logfndata,
 745                        const char *configtext) {
 746   adns_state ads;
 747   int r;
 748
 749   r= init_begin(&ads, flags, logfn, logfndata);
 750   if (r) return r;
 751
 752   readconfigtext(ads,configtext,"<supplied configuration text>");
 753   if (ads->configerrno) {
 754     r= ads->configerrno;
 755     init_abort(ads);
 756     return r;
 757   }
 758
 759   r= init_finish(ads);  if (r) return r;
 760   adns__consistency(ads,0,cc_entex);
 761   *ads_r= ads;
 762   return 0;
 763 }
 764
 765 int adns_init_strcfg(adns_state *ads_r, adns_initflags flags,
 766                      FILE *diagfile, const char *configtext) {
 767   return init_strcfg(ads_r, flags,
 768                      diagfile ? logfn_file : 0, diagfile,
 769                      configtext);
 770 }
 771
 772 int adns_init_logfn(adns_state *newstate_r, adns_initflags flags,
 773                     const char *configtext /*0=>use default config files*/,
 774                     adns_logcallbackfn *logfn /*0=>logfndata is a FILE* */,
 775                     void *logfndata /*0 with logfn==0 => discard*/) {
 776   if (!logfn && logfndata)
 777     logfn= logfn_file;
 778   if (configtext)
 779     return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
 780   else
 781     return init_files(newstate_r, flags, logfn, logfndata);
 782 }
 783
 784 void adns_finish(adns_state ads) {
 785   int i;
 786   adns__consistency(ads,0,cc_entex);
 787   for (;;) {
 788     if (ads->udpw.head) adns__cancel(ads->udpw.head);
 789     else if (ads->tcpw.head) adns__cancel(ads->tcpw.head);
 790     else if (ads->childw.head) adns__cancel(ads->childw.head);
 791     else if (ads->output.head) adns__cancel(ads->output.head);
 792     else if (ads->intdone.head) adns__cancel(ads->output.head);
 793     else break;
 794   }
 795   for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
 796   if (ads->tcpsocket >= 0) close(ads->tcpsocket);
 797   adns__vbuf_free(&ads->tcpsend);
 798   adns__vbuf_free(&ads->tcprecv);
 799   freesearchlist(ads);
 800   free(ads);
 801 }
 802
 803 void adns_forallqueries_begin(adns_state ads) {
 804   adns__consistency(ads,0,cc_entex);
 805   ads->forallnext=
 806     ads->udpw.head ? ads->udpw.head :
 807     ads->tcpw.head ? ads->tcpw.head :
 808     ads->childw.head ? ads->childw.head :
 809     ads->output.head;
 810 }
 811
 812 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
 813   adns_query qu, nqu;
 814
 815   adns__consistency(ads,0,cc_entex);
 816   nqu= ads->forallnext;
 817   for (;;) {
 818     qu= nqu;
 819     if (!qu) return 0;
 820     if (qu->next) {
 821       nqu= qu->next;
 822     } else if (qu == ads->udpw.tail) {
 823       nqu=
 824         ads->tcpw.head ? ads->tcpw.head :
 825         ads->childw.head ? ads->childw.head :
 826         ads->output.head;
 827     } else if (qu == ads->tcpw.tail) {
 828       nqu=
 829         ads->childw.head ? ads->childw.head :
 830         ads->output.head;
 831     } else if (qu == ads->childw.tail) {
 832       nqu= ads->output.head;
 833     } else {
 834       nqu= 0;
 835     }
 836     if (!qu->parent) break;
 837   }
 838   ads->forallnext= nqu;
 839   if (context_r) *context_r= qu->ctx.ext;
 840   return qu;
 841 }