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 *word, *rhs;
 264   char *ep;
 265   unsigned long v;
 266   int i,l;
 267
 268   if (!buf) return;
 269
 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)
 273
 274   while (nextword(&buf,&word,&l)) {
 275     if (OPTION_IS("debug")) {
 276       ads->iflags |= adns_if_debug;
 277       continue;
 278     }
 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);
 284         continue;
 285       }
 286       ads->searchndots= v;
 287       continue;
 288     }
 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;
 298       } else {
 299         configparseerr(ads,fn,lno, "option adns_checkc has bad value `%s' "
 300                        "(must be none, entex or freq", rhs);
 301       }
 302       continue;
 303     }
 304     if (OPTION_STARTS("adns_af:")) {
 305       word= rhs;
 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;
 313         else {
 314           configparseerr(ads,fn,lno, "option adns_af has bad value `%.*s' "
 315                          "(must be `any' or list {`ipv4',`ipv6'},...)",
 316                          i, word);
 317           break;
 318         }
 319         if (!word[i]) break;
 320         word= word + i + 1;
 321       }
 322       continue;
 323     }
 324     adns__diag(ads,-1,0,"%s:%d: unknown option `%.*s'", fn,lno, l,word);
 325   }
 326
 327 #undef OPTION__IS
 328 #undef OPTION_IS
 329 #undef OPTION_STARTS
 330 }
 331
 332 static void ccf_clearnss(adns_state ads, const char *fn,
 333                          int lno, const char *buf) {
 334   ads->nservers= 0;
 335 }
 336
 337 static void ccf_include(adns_state ads, const char *fn,
 338                         int lno, const char *buf) {
 339   if (!*buf) {
 340     configparseerr(ads,fn,lno,"`include' directive with no filename");
 341     return;
 342   }
 343   readconfig(ads,buf,1);
 344 }
 345
 346 static void ccf_lookup(adns_state ads, const char *fn, int lno,
 347                        const char *buf) {
 348   int found_bind=0;
 349   const char *word;
 350   int l;
 351
 352   if (!*buf) {
 353     configparseerr(ads,fn,lno,"`lookup' directive with no databases");
 354     return;
 355   }
 356
 357   while (nextword(&buf,&word,&l)) {
 358     if (l==4 && !memcmp(word,"bind",4)) {
 359       found_bind=1;
 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);
 364       found_bind=-1;
 365     } else {
 366       adns__diag(ads,-1,0,"%s:%d: unknown `lookup' database `%.*s'",
 367                  fn,lno, l,word);
 368       found_bind=-1;
 369     }
 370   }
 371   if (!found_bind)
 372     adns__diag(ads,-1,0,"%s:%d: `lookup' specified, but not `bind'", fn,lno);
 373 }
 374
 375 static const struct configcommandinfo {
 376   const char *name;
 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 */
 387   {  0                                   }
 388 };
 389
 390 typedef union {
 391   FILE *file;
 392   const char *text;
 393 } getline_ctx;
 394
 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;
 398   int c, i;
 399   char *p;
 400
 401   p= buf;
 402   buflen--;
 403   i= 0;
 404
 405   for (;;) { /* loop over chars */
 406     if (i == buflen) {
 407       adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 408       goto x_badline;
 409     }
 410     c= getc(file);
 411     if (!c) {
 412       adns__diag(ads,-1,0,"%s:%d: line contains nul, ignored",filename,lno);
 413       goto x_badline;
 414     } else if (c == '\n') {
 415       break;
 416     } else if (c == EOF) {
 417       if (ferror(file)) {
 418         saveerr(ads,errno);
 419         adns__diag(ads,-1,0,"%s:%d: read error: %s",
 420                    filename,lno,strerror(errno));
 421         return -1;
 422       }
 423       if (!i) return -1;
 424       break;
 425     } else {
 426       *p++= c;
 427       i++;
 428     }
 429   }
 430
 431   *p++= 0;
 432   return i;
 433
 434  x_badline:
 435   saveerr(ads,EINVAL);
 436   while ((c= getc(file)) != EOF && c != '\n');
 437   return -2;
 438 }
 439
 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;
 443   int l;
 444
 445   if (!cp || !*cp) return -1;
 446
 447   if (*cp == ';' || *cp == '\n') cp++;
 448   l= strcspn(cp,";\n");
 449   src_io->text = cp+l;
 450
 451   if (l >= buflen) {
 452     adns__diag(ads,-1,0,"%s:%d: line too long, ignored",filename,lno);
 453     saveerr(ads,EINVAL);
 454     return -2;
 455   }
 456
 457   memcpy(buf,cp,l);
 458   buf[l]= 0;
 459   return l;
 460 }
 461
 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.
 469                                */
 470                               getline_ctx gl_ctx) {
 471   char linebuf[2000], *p, *q;
 472   int lno, l, dirl;
 473   const struct configcommandinfo *ccip;
 474
 475   for (lno=1;
 476        (l= getline(ads,&gl_ctx, filename,lno, linebuf,sizeof(linebuf))) != -1;
 477        lno++) {
 478     if (l == -2) continue;
 479     while (l>0 && ctype_whitespace(linebuf[l-1])) l--;
 480     linebuf[l]= 0;
 481     p= linebuf;
 482     while (ctype_whitespace(*p)) p++;
 483     if (*p == '#' || *p == ';' || !*p) continue;
 484     q= p;
 485     while (*q && !ctype_whitespace(*q)) q++;
 486     dirl= q-p;
 487     for (ccip=configcommandinfos;
 488          ccip->name &&
 489            !(strlen(ccip->name)==dirl && !memcmp(ccip->name,p,q-p));
 490          ccip++);
 491     if (!ccip->name) {
 492       adns__diag(ads,-1,0,"%s:%d: unknown configuration directive `%.*s'",
 493                  filename,lno,(int)(q-p),p);
 494       continue;
 495     }
 496     while (ctype_whitespace(*q)) q++;
 497     ccip->fn(ads,filename,lno,q);
 498   }
 499 }
 500
 501 static const char *instrum_getenv(adns_state ads, const char *envvar) {
 502   const char *value;
 503
 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);
 508   return value;
 509 }
 510
 511 static void readconfig(adns_state ads, const char *filename, int warnmissing) {
 512   getline_ctx gl_ctx;
 513
 514   gl_ctx.file= fopen(filename,"r");
 515   if (!gl_ctx.file) {
 516     if (errno == ENOENT) {
 517       if (warnmissing)
 518         adns__debug(ads,-1,0, "configuration file"
 519                     " `%s' does not exist",filename);
 520       return;
 521     }
 522     saveerr(ads,errno);
 523     adns__diag(ads,-1,0,"cannot open configuration file `%s': %s",
 524                filename,strerror(errno));
 525     return;
 526   }
 527
 528   readconfiggeneric(ads,filename,gl_file,gl_ctx);
 529
 530   fclose(gl_ctx.file);
 531 }
 532
 533 static void readconfigtext(adns_state ads, const char *text,
 534                            const char *showname) {
 535   getline_ctx gl_ctx;
 536
 537   gl_ctx.text= text;
 538   readconfiggeneric(ads,showname,gl_text,gl_ctx);
 539 }
 540
 541 static void readconfigenv(adns_state ads, const char *envvar) {
 542   const char *filename;
 543
 544   if (ads->iflags & adns_if_noenv) {
 545     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 546     return;
 547   }
 548   filename= instrum_getenv(ads,envvar);
 549   if (filename) readconfig(ads,filename,1);
 550 }
 551
 552 static void readconfigenvtext(adns_state ads, const char *envvar) {
 553   const char *textdata;
 554
 555   if (ads->iflags & adns_if_noenv) {
 556     adns__debug(ads,-1,0,"not checking environment variable `%s'",envvar);
 557     return;
 558   }
 559   textdata= instrum_getenv(ads,envvar);
 560   if (textdata) readconfigtext(ads,textdata,envvar);
 561 }
 562
 563
 564 int adns__setnonblock(adns_state ads, int fd) {
 565   int r;
 566
 567   r= fcntl(fd,F_GETFL,0); if (r<0) return errno;
 568   r |= O_NONBLOCK;
 569   r= fcntl(fd,F_SETFL,r); if (r<0) return errno;
 570   return 0;
 571 }
 572
 573 static int init_begin(adns_state *ads_r, adns_initflags flags,
 574                       adns_logcallbackfn *logfn, void *logfndata) {
 575   adns_state ads;
 576   pid_t pid;
 577
 578   if (flags & ~(adns_initflags)(0x4fff))
 579     /* 0x4000 is reserved for `harmless' future expansion */
 580     return ENOSYS;
 581
 582   ads= malloc(sizeof(*ads)); if (!ads) return errno;
 583
 584   ads->iflags= flags;
 585   ads->logfn= logfn;
 586   ads->logfndata= logfndata;
 587   ads->configerrno= 0;
 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);
 593   ads->forallnext= 0;
 594   ads->nextid= 0x311f;
 595   ads->nudpsockets= 0;
 596   ads->tcpsocket= -1;
 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;
 601   ads->searchndots= 1;
 602   ads->tcpstate= server_disconnected;
 603   timerclear(&ads->tcptimeout);
 604   ads->searchlist= 0;
 605
 606   pid= getpid();
 607   ads->rand48xsubi[0]= pid;
 608   ads->rand48xsubi[1]= (unsigned long)pid >> 16;
 609   ads->rand48xsubi[2]= pid ^ ((unsigned long)pid >> 16);
 610
 611   *ads_r= ads;
 612   return 0;
 613 }
 614
 615 static int init_finish(adns_state ads) {
 616   struct sockaddr_in sin;
 617   struct protoent *proto;
 618   struct udpsocket *udp;
 619   int i;
 620   int r;
 621
 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));
 630   }
 631
 632   proto= getprotobyname("udp"); if (!proto) { r= ENOPROTOOPT; goto x_free; }
 633   ads->nudpsockets= 0;
 634   for (i=0; i<ads->nservers; i++) {
 635     if (adns__udpsocket_by_af(ads, ads->servers[i].addr.sa.sa_family))
 636       continue;
 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; }
 642     ads->nudpsockets++;
 643     r= adns__setnonblock(ads,udp->fd);
 644     if (r) { r= errno; goto x_closeudp; }
 645   }
 646
 647   return 0;
 648
 649  x_closeudp:
 650   for (i=0; i<ads->nudpsockets; i++) close(ads->udpsockets[i].fd);
 651  x_free:
 652   free(ads);
 653   return r;
 654 }
 655
 656 static void init_abort(adns_state ads) {
 657   if (ads->nsearchlist) {
 658     free(ads->searchlist[0]);
 659     free(ads->searchlist);
 660   }
 661   free(ads);
 662 }
 663
 664 static void logfn_file(adns_state ads, void *logfndata,
 665                        const char *fmt, va_list al) {
 666   vfprintf(logfndata,fmt,al);
 667 }
 668
 669 static int init_files(adns_state *ads_r, adns_initflags flags,
 670                       adns_logcallbackfn *logfn, void *logfndata) {
 671   adns_state ads;
 672   const char *res_options, *adns_res_options;
 673   int r;
 674
 675   r= init_begin(&ads, flags, logfn, logfndata);
 676   if (r) return r;
 677
 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);
 682
 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");
 687
 688   readconfigenvtext(ads,"RES_CONF_TEXT");
 689   readconfigenvtext(ads,"ADNS_RES_CONF_TEXT");
 690
 691   ccf_options(ads,"RES_OPTIONS",-1,res_options);
 692   ccf_options(ads,"ADNS_RES_OPTIONS",-1,adns_res_options);
 693
 694   ccf_search(ads,"LOCALDOMAIN",-1,instrum_getenv(ads,"LOCALDOMAIN"));
 695   ccf_search(ads,"ADNS_LOCALDOMAIN",-1,instrum_getenv(ads,"ADNS_LOCALDOMAIN"));
 696
 697   if (ads->configerrno && ads->configerrno != EINVAL) {
 698     r= ads->configerrno;
 699     init_abort(ads);
 700     return r;
 701   }
 702
 703   r= init_finish(ads);
 704   if (r) return r;
 705
 706   adns__consistency(ads,0,cc_entex);
 707   *ads_r= ads;
 708   return 0;
 709 }
 710
 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);
 713 }
 714
 715 static int init_strcfg(adns_state *ads_r, adns_initflags flags,
 716                        adns_logcallbackfn *logfn, void *logfndata,
 717                        const char *configtext) {
 718   adns_state ads;
 719   int r;
 720
 721   r= init_begin(&ads, flags, logfn, logfndata);
 722   if (r) return r;
 723
 724   readconfigtext(ads,configtext,"<supplied configuration text>");
 725   if (ads->configerrno) {
 726     r= ads->configerrno;
 727     init_abort(ads);
 728     return r;
 729   }
 730
 731   r= init_finish(ads);  if (r) return r;
 732   adns__consistency(ads,0,cc_entex);
 733   *ads_r= ads;
 734   return 0;
 735 }
 736
 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,
 741                      configtext);
 742 }
 743
 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)
 749     logfn= logfn_file;
 750   if (configtext)
 751     return init_strcfg(newstate_r, flags, logfn, logfndata, configtext);
 752   else
 753     return init_files(newstate_r, flags, logfn, logfndata);
 754 }
 755
 756 void adns_finish(adns_state ads) {
 757   int i;
 758   adns__consistency(ads,0,cc_entex);
 759   for (;;) {
 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);
 765     else break;
 766   }
 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);
 771   freesearchlist(ads);
 772   free(ads);
 773 }
 774
 775 void adns_forallqueries_begin(adns_state ads) {
 776   adns__consistency(ads,0,cc_entex);
 777   ads->forallnext=
 778     ads->udpw.head ? ads->udpw.head :
 779     ads->tcpw.head ? ads->tcpw.head :
 780     ads->childw.head ? ads->childw.head :
 781     ads->output.head;
 782 }
 783
 784 adns_query adns_forallqueries_next(adns_state ads, void **context_r) {
 785   adns_query qu, nqu;
 786
 787   adns__consistency(ads,0,cc_entex);
 788   nqu= ads->forallnext;
 789   for (;;) {
 790     qu= nqu;
 791     if (!qu) return 0;
 792     if (qu->next) {
 793       nqu= qu->next;
 794     } else if (qu == ads->udpw.tail) {
 795       nqu=
 796         ads->tcpw.head ? ads->tcpw.head :
 797         ads->childw.head ? ads->childw.head :
 798         ads->output.head;
 799     } else if (qu == ads->tcpw.tail) {
 800       nqu=
 801         ads->childw.head ? ads->childw.head :
 802         ads->output.head;
 803     } else if (qu == ads->childw.tail) {
 804       nqu= ads->output.head;
 805     } else {
 806       nqu= 0;
 807     }
 808     if (!qu->parent) break;
 809   }
 810   ads->forallnext= nqu;
 811   if (context_r) *context_r= qu->ctx.ext;
 812   return qu;
 813 }