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

   1 /*
   2  * query.c
   3  * - overall query management (allocation, completion)
   4  * - per-query memory management
   5  * - query submission and cancellation (user-visible and internal)
   6  */
   7 /*
   8  *  This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
   9  *
  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 2, or (at your option)
  13  *  any later version.
  14  *
  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.
  19  *
  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,
  22  *  Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23  */
  24
  25 #include "internal.h"
  26
  27 #include <stdlib.h>
  28 #include <unistd.h>
  29 #include <errno.h>
  30
  31 #include <sys/time.h>
  32
  33 #include "internal.h"
  34
  35 int adns__internal_submit(adns_state ads, adns_query *query_r,
  36                           adns_rrtype type, vbuf *qumsg_vb, int id,
  37                           adns_queryflags flags, struct timeval now,
  38                           adns_status failstat, const qcontext *ctx) {
  39   adns_query qu;
  40   adns_status stat;
  41   int ol, id, r;
  42   struct timeval now;
  43   const typeinfo *typei;
  44   adns_query qu;
  45
  46   qu= malloc(sizeof(*qu)); if (!qu) goto x_nomemory;
  47   qu->answer= malloc(sizeof(*qu->answer)); if (!qu->answer) goto x_freequ_nomemory;
  48
  49   qu->state= query_udp;
  50   qu->back= qu->next= qu->parent= 0;
  51   LIST_INIT(qu->children);
  52   qu->siblings.next= qu->siblings.back= 0;
  53   qu->allocations= 0;
  54   qu->interim_allocd= 0;
  55   qu->perm_used= 0;
  56
  57   qu->typei= adns__findtype(type);
  58   adns__vbuf_init(&qu->vb);
  59
  60   qu->cname_dgram= 0;
  61   qu->cname_dglen= qu->cname_begin= 0;
  62
  63   qu->id= id;
  64   qu->flags= flags;
  65   qu->udpretries= 0;
  66   qu->udpnextserver= 0;
  67   qu->udpsent= qu->tcpfailed= 0;
  68   timerclear(&qu->timeout);
  69   memcpy(&qu->context,ctx,sizeof(qu->context));
  70   memcpy(qu->owner,owner,ol); qu->owner[ol]= 0;
  71
  72   qu->answer->status= adns_s_ok;
  73   qu->answer->cname= 0;
  74   qu->answer->type= type;
  75   qu->answer->nrrs= 0;
  76   qu->answer->rrs= 0;
  77
  78   if (qu->typei) {
  79     qu->answer->rrsz= qu->rrsz;
  80   } else {
  81     qu->answer->rrsz= -1;
  82     failstat= adns_s_notimplemented;
  83   }
  84
  85   *query_r= qu;
  86
  87   qu->query_dgram= malloc(qumsg_vb->used);
  88   if (!qu->query_dgram) {
  89     adns__query_fail(ads,qu,adns_s_nomemory);
  90     return;
  91   }
  92   memcpy(qu->query_dgram,qumsg_vb->buf,qumsg_vb->used);
  93   qu->vb= *qumsg_vb;
  94   adns__vbuf_init(qumsg_vb);
  95
  96   if (failstat) {
  97     adns__query_fail(ads,qu,failstat);
  98     return;
  99   }
 100   adns__query_udp(ads,qu,now);
 101   adns__autosys(ads,now);
 102
 103   return 0;
 104
 105  x_freequ_nomemory:
 106   free(qu);
 107  x_nomemory:
 108   free(query_dgram);
 109   return adns_s_nomemory;
 110 }
 111
 112 int adns_submit(adns_state ads,
 113                 const char *owner,
 114                 adns_rrtype type,
 115                 adns_queryflags flags,
 116                 void *context,
 117                 adns_query *query_r) {
 118   qcontext ctx;
 119   int id;
 120   vbuf vb;
 121
 122   ctx.ext= context;
 123   r= gettimeofday(&now,0); if (r) return errno;
 124   id= 0;
 125
 126   adns__vbuf_init(&vb);
 127
 128   ol= strlen(owner);
 129   if (ol<=1 || ol>DNS_MAXDOMAIN+1) { stat= adns_s_invaliddomain; goto xit; }
 130
 131   if (owner[ol-1]=='.' && owner[ol-2]!='\\') { flags &= ~adns_qf_search; ol--; }
 132
 133   stat= adns__mkquery(ads,&vb, &id, owner,ol, typei,flags);
 134
 135  xit:
 136   return adns__internal_submit(ads,query_r, type,&vb,id, flags,now, stat,&ctx);
 137 }
 138
 139 int adns_synchronous(adns_state ads,
 140                      const char *owner,
 141                      adns_rrtype type,
 142                      adns_queryflags flags,
 143                      adns_answer **answer_r) {
 144   adns_query qu;
 145   int r;
 146
 147   r= adns_submit(ads,owner,type,flags,0,&qu);
 148   if (r) return r;
 149
 150   do {
 151     r= adns_wait(ads,&qu,answer_r,0);
 152   } while (r==EINTR);
 153   if (r) adns_cancel(ads,qu);
 154   return r;
 155 }
 156
 157 void adns_cancel(adns_state ads, adns_query query) {
 158   abort(); /* fixme */
 159 }
 160
 161 void *adns__alloc_interim(adns_state ads, adns_query qu, size_t sz) {
 162   allocnode *an;
 163
 164   assert(!qu->final_allocspace);
 165   sz= MEM_ROUND(sz);
 166   an= malloc(MEM_ROUND(MEM_ROUND(sizeof(*an)) + sz));
 167   if (!an) {
 168     adns__query_fail(ads,qu,adns_s_nolocalmem);
 169     return 0;
 170   }
 171   qu->permalloclen += sz;
 172   an->next= qu->allocations;
 173   qu->allocations= an;
 174   return (byte*)an + MEM_ROUND(sizeof(*an));
 175 }
 176
 177 void *adns__alloc_final(adns_query qu, size_t sz) {
 178   /* When we're in the _final stage, we _subtract_ from interim_alloc'd
 179    * each allocation, and use final_allocspace to point to the next free
 180    * bit.
 181    */
 182   void *rp;
 183
 184   sz= MEM_ROUND(sz);
 185   rp= qu->final_allocspace;
 186   assert(rp);
 187   qu->interim_allocd -= sz;
 188   assert(qu->interim_allocd>=0);
 189   qu->final_allocspace= (byte*)rp + sz;
 190   return rp;
 191 }
 192
 193 void adns__reset_cnameonly(adns_state ads, adns_query qu) {
 194   assert(qu->final_allocspace);
 195   qu->answer->nrrs= 0;
 196   qu->answer->rrs= 0;
 197   qu->interim_allocd= qu->answer->cname ? MEM_ROUND(strlen(qu->answer->cname)+1) : 0;
 198 }
 199
 200 static void adns__query_done(adns_state ads, adns_query qu) {
 201   adns_answer *ans;
 202   allocnode *an, *ann;
 203   int i;
 204
 205   qu->answer= ans= realloc(qu->answer,
 206                            MEM_ROUND(MEM_ROUND(sizeof(*ans)) +
 207                                      qu->interim_allocd));
 208   qu->final_allocspace= (byte*)qu->answer + MEM_ROUND(sizeof(*ans));
 209
 210   adns__makefinal_str(qu,&ans->cname);
 211   if (ans->nrrs) {
 212     adns__makefinal_block(qu,&ans->rrs.untyped,ans->rrsz*ans->nrrs);
 213     for (i=0; i<ans->nrrs; i++)
 214       qu->typei->makefinal(ads,qu,ans->rrs.bytes+ans->rrsz*i);
 215   }
 216
 217   for (an= qu->allocations; an; an= ann) { ann= an->next; free(an); }
 218
 219   adns__vbuf_free(&qu->vb);
 220
 221   qu->id= -1;
 222   LIST_LINK_TAIL(ads->output,qu);
 223 }
 224
 225 void adns__query_fail(adns_state ads, adns_query qu, adns_status stat) {
 226   adns__reset_cnameonly(ads,qu);
 227   qu->answer->status= stat;
 228   adns__query_done(ads,qu);
 229 }
 230
 231 void adns__makefinal_str(adns_query qu, char **strp) {
 232   int l;
 233   char *before, *after;
 234
 235   before= *strp;
 236   l= strlen(before)+1;
 237   after= adns__alloc_final(qu,l);
 238   memcpy(after,before,l);
 239   *strp= after;
 240 }
 241
 242 void adns__makefinal_block(adns__query qu, void **blpp, size_t sz) {
 243   void *after;
 244
 245   after= adns__alloc_final(qu,sz);
 246   memcpy(after,*blpp,sz);
 247   *blpp= after;
 248 }
 249