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

   1 /*
   2  * general.c
   3  * - diagnostic functions
   4  * - vbuf handling
   5  */
   6 /*
   7  *  This file is
   8  *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
   9  *
  10  *  It is part of adns, which is
  11  *    Copyright (C) 1997-1999 Ian Jackson <ian@davenant.greenend.org.uk>
  12  *    Copyright (C) 1999 Tony Finch <dot@dotat.at>
  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 2, 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  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 #include <stdlib.h>
  30 #include <unistd.h>
  31
  32 #include <sys/types.h>
  33 #include <sys/socket.h>
  34 #include <netinet/in.h>
  35 #include <arpa/inet.h>
  36
  37 #include "internal.h"
  38
  39 /* Core diagnostic functions */
  40
  41 void adns__vdiag(adns_state ads, const char *pfx, adns_initflags prevent,
  42                  int serv, adns_query qu, const char *fmt, va_list al) {
  43   const char *bef, *aft;
  44   vbuf vb;
  45
  46   if (!ads->diagfile ||
  47       (!(ads->iflags & adns_if_debug) && (!prevent || (ads->iflags & prevent))))
  48     return;
  49
  50   if (ads->iflags & adns_if_logpid) {
  51     fprintf(ads->diagfile,"adns%s [%ld]: ",pfx,(long)getpid());
  52   } else {
  53     fprintf(ads->diagfile,"adns%s: ",pfx);
  54   }
  55
  56   vfprintf(ads->diagfile,fmt,al);
  57
  58   bef= " (";
  59   aft= "\n";
  60
  61   if (qu && qu->query_dgram) {
  62     adns__vbuf_init(&vb);
  63     fprintf(ads->diagfile,"%sQNAME=%s, QTYPE=%s",
  64             bef,
  65             adns__diag_domain(qu->ads,-1,0, &vb,
  66                               qu->query_dgram,qu->query_dglen,DNS_HDRSIZE),
  67             qu->typei ? qu->typei->rrtname : "<unknown>");
  68     if (qu->typei && qu->typei->fmtname)
  69       fprintf(ads->diagfile,"(%s)",qu->typei->fmtname);
  70     bef=", "; aft=")\n";
  71   }
  72
  73   if (serv>=0) {
  74     fprintf(ads->diagfile,"%sNS=%s",bef,inet_ntoa(ads->servers[serv].addr));
  75     bef=", "; aft=")\n";
  76   }
  77
  78   fputs(aft,ads->diagfile);
  79 }
  80
  81 void adns__debug(adns_state ads, int serv, adns_query qu, const char *fmt, ...) {
  82   va_list al;
  83
  84   va_start(al,fmt);
  85   adns__vdiag(ads," debug",0,serv,qu,fmt,al);
  86   va_end(al);
  87 }
  88
  89 void adns__warn(adns_state ads, int serv, adns_query qu, const char *fmt, ...) {
  90   va_list al;
  91
  92   va_start(al,fmt);
  93   adns__vdiag(ads," warning",adns_if_noerrprint|adns_if_noserverwarn,serv,qu,fmt,al);
  94   va_end(al);
  95 }
  96
  97 void adns__diag(adns_state ads, int serv, adns_query qu, const char *fmt, ...) {
  98   va_list al;
  99
 100   va_start(al,fmt);
 101   adns__vdiag(ads,"",adns_if_noerrprint,serv,qu,fmt,al);
 102   va_end(al);
 103 }
 104
 105 /* vbuf functions */
 106
 107 void adns__vbuf_init(vbuf *vb) {
 108   vb->used= vb->avail= 0; vb->buf= 0;
 109 }
 110
 111 int adns__vbuf_ensure(vbuf *vb, int want) {
 112   void *nb;
 113
 114   if (vb->avail >= want) return 1;
 115   nb= realloc(vb->buf,want); if (!nb) return 0;
 116   vb->buf= nb;
 117   vb->avail= want;
 118   return 1;
 119 }
 120
 121 void adns__vbuf_appendq(vbuf *vb, const byte *data, int len) {
 122   memcpy(vb->buf+vb->used,data,len);
 123   vb->used+= len;
 124 }
 125
 126 int adns__vbuf_append(vbuf *vb, const byte *data, int len) {
 127   int newlen;
 128   void *nb;
 129
 130   newlen= vb->used+len;
 131   if (vb->avail < newlen) {
 132     if (newlen<20) newlen= 20;
 133     newlen <<= 1;
 134     nb= realloc(vb->buf,newlen);
 135     if (!nb) { newlen= vb->used+len; nb= realloc(vb->buf,newlen); }
 136     if (!nb) return 0;
 137     vb->buf= nb;
 138     vb->avail= newlen;
 139   }
 140   adns__vbuf_appendq(vb,data,len);
 141   return 1;
 142 }
 143
 144 int adns__vbuf_appendstr(vbuf *vb, const char *data) {
 145   int l;
 146   l= strlen(data);
 147   return adns__vbuf_append(vb,data,l);
 148 }
 149
 150 void adns__vbuf_free(vbuf *vb) {
 151   free(vb->buf);
 152   adns__vbuf_init(vb);
 153 }
 154
 155 /* Additional diagnostic functions */
 156
 157 const char *adns__diag_domain(adns_state ads, int serv, adns_query qu,
 158                               vbuf *vb, const byte *dgram, int dglen, int cbyte) {
 159   adns_status st;
 160
 161   st= adns__parse_domain(ads,serv,qu,vb, pdf_quoteok, dgram,dglen,&cbyte,dglen);
 162   if (st == adns_s_nomemory) {
 163     return "<cannot report domain... out of memory>";
 164   }
 165   if (st) {
 166     vb->used= 0;
 167     if (!(adns__vbuf_appendstr(vb,"<bad format... ") &&
 168           adns__vbuf_appendstr(vb,adns_strerror(st)) &&
 169           adns__vbuf_appendstr(vb,">") &&
 170           adns__vbuf_append(vb,"",1))) {
 171       return "<cannot report bad format... out of memory>";
 172     }
 173   }
 174   if (!vb->used) {
 175     adns__vbuf_appendstr(vb,"<truncated ...>");
 176     adns__vbuf_append(vb,"",1);
 177   }
 178   return vb->buf;
 179 }
 180
 181 adns_status adns_rr_info(adns_rrtype type,
 182                          const char **rrtname_r, const char **fmtname_r,
 183                          int *len_r,
 184                          const void *datap, char **data_r) {
 185   const typeinfo *typei;
 186   vbuf vb;
 187   adns_status st;
 188
 189   typei= adns__findtype(type);
 190   if (!typei) return adns_s_unknownrrtype;
 191
 192   if (rrtname_r) *rrtname_r= typei->rrtname;
 193   if (fmtname_r) *fmtname_r= typei->fmtname;
 194   if (len_r) *len_r= typei->rrsz;
 195
 196   if (!datap) return adns_s_ok;
 197
 198   adns__vbuf_init(&vb);
 199   st= typei->convstring(&vb,datap);
 200   if (st) goto x_freevb;
 201   if (!adns__vbuf_append(&vb,"",1)) { st= adns_s_nomemory; goto x_freevb; }
 202   assert(strlen(vb.buf) == vb.used-1);
 203   *data_r= realloc(vb.buf,vb.used);
 204   if (!*data_r) *data_r= vb.buf;
 205   return adns_s_ok;
 206
 207  x_freevb:
 208   adns__vbuf_free(&vb);
 209   return st;
 210 }
 211
 212
 213 #define SINFO(n,s) { adns_s_##n, #n, s }
 214
 215 static const struct sinfo {
 216   adns_status st;
 217   const char *abbrev;
 218   const char *string;
 219 } sinfos[]= {
 220   SINFO(  ok,                  "OK"                                            ),
 221
 222   SINFO(  nomemory,            "Out of memory"                                 ),
 223   SINFO(  unknownrrtype,       "Query not implemented in DNS library"          ),
 224   SINFO(  systemfail,          "General resolver or system failure"            ),
 225
 226   SINFO(  timeout,             "DNS query timed out"                           ),
 227   SINFO(  allservfail,         "All nameservers failed"                        ),
 228   SINFO(  norecurse,           "Recursion denied by nameserver"                ),
 229   SINFO(  invalidresponse,     "Nameserver sent bad response"                  ),
 230   SINFO(  unknownformat,       "Nameserver used unknown format"                ),
 231
 232   SINFO(  rcodeservfail,       "Nameserver reports failure"                    ),
 233   SINFO(  rcodeformaterror,    "Query not understood by nameserver"            ),
 234   SINFO(  rcodenotimplemented, "Query not implemented by nameserver"           ),
 235   SINFO(  rcoderefused,        "Query refused by nameserver"                   ),
 236   SINFO(  rcodeunknown,        "Nameserver sent unknown response code"         ),
 237
 238   SINFO(  inconsistent,        "Inconsistent resource records in DNS"          ),
 239   SINFO(  prohibitedcname,     "DNS alias found where canonical name wanted"   ),
 240   SINFO(  answerdomaininvalid, "Found syntactically invalid domain name"       ),
 241   SINFO(  answerdomaintoolong, "Found overly-long domain name"                 ),
 242   SINFO(  invaliddata,         "Found invalid DNS data"                        ),
 243
 244   SINFO(  querydomainwrong,    "Domain invalid for particular DNS query type"  ),
 245   SINFO(  querydomaininvalid,  "Domain name is syntactically invalid"          ),
 246   SINFO(  querydomaintoolong,  "Domain name is too long"                       ),
 247
 248   SINFO(  nxdomain,            "No such domain"                                ),
 249   SINFO(  nodata,              "No such data"                                  )
 250 };
 251
 252 static int si_compar(const void *key, const void *elem) {
 253   const adns_status *st= key;
 254   const struct sinfo *si= elem;
 255
 256   return *st < si->st ? -1 : *st > si->st ? 1 : 0;
 257 }
 258
 259 static const struct sinfo *findsinfo(adns_status st) {
 260   return bsearch(&st,sinfos,sizeof(sinfos)/sizeof(*sinfos),sizeof(*sinfos),si_compar);
 261 }
 262
 263 const char *adns_strerror(adns_status st) {
 264   const struct sinfo *si;
 265
 266   si= findsinfo(st);
 267   return si->string;
 268 }
 269
 270 const char *adns_errabbrev(adns_status st) {
 271   const struct sinfo *si;
 272
 273   si= findsinfo(st);
 274   return si->abbrev;
 275 }
 276
 277
 278 #define STINFO(max) { adns_s_max_##max, #max }
 279
 280 static const struct stinfo {
 281   adns_status stmax;
 282   const char *abbrev;
 283 } stinfos[]= {
 284   { adns_s_ok, "ok" },
 285   STINFO(  localfail   ),
 286   STINFO(  remotefail  ),
 287   STINFO(  tempfail    ),
 288   STINFO(  misconfig   ),
 289   STINFO(  misquery    ),
 290   STINFO(  permfail    )
 291 };
 292
 293 static int sti_compar(const void *key, const void *elem) {
 294   const adns_status *st= key;
 295   const struct stinfo *sti= elem;
 296
 297   adns_status here, min, max;
 298
 299   here= *st;
 300   min= (sti==stinfos) ? 0 : sti[-1].stmax+1;
 301   max= sti->stmax;
 302
 303   return here < min  ? -1 : here > max ? 1 : 0;
 304 }
 305
 306 const char *adns_errtypeabbrev(adns_status st) {
 307   const struct stinfo *sti;
 308
 309   sti= bsearch(&st,stinfos,sizeof(stinfos)/sizeof(*stinfos),sizeof(*stinfos),sti_compar);
 310   return sti->abbrev;
 311 }
 312
 313
 314 void adns__isort(void *array, int nobjs, int sz, void *tempbuf,
 315                  int (*needswap)(void *context, const void *a, const void *b),
 316                  void *context) {
 317   byte *data= array;
 318   int i, place;
 319
 320   for (i=0; i<nobjs; i++) {
 321     for (place= i;
 322          place>0 && needswap(context, data + (place-1)*sz, data + i*sz);
 323          place--);
 324     if (place != i) {
 325       memcpy(tempbuf, data + i*sz, sz);
 326       memmove(data + (place+1)*sz, data + place*sz, (i-place)*sz);
 327       memcpy(data + place*sz, tempbuf, sz);
 328     }
 329   }
 330 }
 331
 332 /* SIGPIPE protection. */
 333
 334 void adns__sigpipe_protect(adns_state ads) {
 335   sigset_t toblock;
 336   struct sigaction sa;
 337   int r;
 338
 339   if (ads->iflags & adns_if_nosigpipe) return;
 340
 341   sigfillset(&toblock);
 342   sigdelset(&toblock,SIGPIPE);
 343
 344   sa.sa_handler= SIG_IGN;
 345   sigfillset(&sa.sa_mask);
 346   sa.sa_flags= 0;
 347
 348   r= sigprocmask(SIG_SETMASK,&toblock,&ads->stdsigmask); assert(!r);
 349   r= sigaction(SIGPIPE,&sa,&ads->stdsigpipe); assert(!r);
 350 }
 351
 352 void adns__sigpipe_unprotect(adns_state ads) {
 353   int r;
 354
 355   if (ads->iflags & adns_if_nosigpipe) return;
 356
 357   r= sigaction(SIGPIPE,&ads->stdsigpipe,0); assert(!r);
 358   r= sigprocmask(SIG_SETMASK,&ads->stdsigmask,0); assert(!r);
 359 }