-/**/
+/*
+ * reply.c
+ * - main handling and parsing routine for received datagrams
+ */
+/*
+ * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
#include "internal.h"
-static void cname_recurse(adns_state ads, adns_query qu, adns_queryflags xflags) {
+static void cname_recurse(adns_query qu, adns_queryflags xflags) {
abort(); /* FIXME */
}
void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
int serv, struct timeval now) {
int cbyte, rrstart, wantedrrs, rri, foundsoa, foundns;
- int id, f1, f2, qdcount, ancount, nscount, arcount, flg_ra, flg_tc;
- int rrtype, rrclass, rdlength, rdstart, ownermatched, ownerstart;
+ int id, f1, f2, qdcount, ancount, nscount, arcount;
+ int flg_ra, flg_rd, flg_tc, flg_qr, opcode;
+ int rrtype, rrclass, rdlength, rdstart, ownermatched, l;
int anstart, nsstart, arstart;
- int currentrrs;
adns_query qu, nqu;
dns_rcode rcode;
adns_status st;
-= 0;
if (dglen<DNS_HDRSIZE) {
- adns__diag(ads,serv,"received datagram too short for message header (%d)",dglen);
+ adns__diag(ads,serv,0,"received datagram too short for message header (%d)",dglen);
return;
}
GET_W(cbyte,id);
GET_W(cbyte,arcount);
assert(cbyte == DNS_HDRSIZE);
+ flg_qr= f1&0x80;
+ opcode= (f1&0x78)>>3;
flg_tc= f1&0x20;
+ flg_rd= f1&0x01;
flg_ra= f2&0x80;
+ rcode= (f1&0x0f);
- if (f1&0x80) {
- adns__diag(ads,serv,"server sent us a query, not a response");
+ if (flg_qr) {
+ adns__diag(ads,serv,0,"server sent us a query, not a response");
return;
}
- if (f1&0x70) {
- adns__diag(ads,serv,"server sent us unknown opcode %d (wanted 0=QUERY)",
- (f1>>4)&0x70);
+ if (opcode) {
+ adns__diag(ads,serv,0,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
return;
}
if (!qdcount) {
- adns__diag(ads,serv,"server sent reply without quoting our question");
+ adns__diag(ads,serv,0,"server sent reply without quoting our question");
return;
} else if (qdcount>1) {
- adns__diag(ads,serv,"server claimed to answer %d questions with one message",
+ adns__diag(ads,serv,0,"server claimed to answer %d questions with one message",
qdcount);
return;
}
for (qu= ads->timew.head; qu; qu= nqu) {
nqu= qu->next;
if (qu->id != id) continue;
- if (dglen < qu->querylen) continue;
- if (memcmp(qu->querymsg+DNS_HDRSIZE,dgram+DNS_HDRSIZE,qu->querylen-DNS_HDRSIZE))
+ if (dglen < qu->query_dglen) continue;
+ if (memcmp(qu->query_dgram+DNS_HDRSIZE,
+ dgram+DNS_HDRSIZE,
+ qu->query_dglen-DNS_HDRSIZE))
continue;
break;
}
- assert(qu->cnameoff == -1);
- anstart= qu->querylen;
+ anstart= qu->query_dglen;
if (!qu) {
- adns__debug(ads,serv,"reply not found (id=%02x)",id);
+ adns__debug(ads,serv,0,"reply not found (id=%02x)",id);
return;
}
LIST_UNLINK(ads->timew,qu);
/* We're definitely going to do something with this query now */
- if (!(f1&0x01)) {
- adns__diag(ads,serv,"server thinks we didn't ask for recursive lookup");
- adns__query_fail(ads,qu,adns_s_serverfaulty);
- return;
- }
-
- rcode= (f1&0x0f);
switch (rcode) {
case rcode_noerror:
case rcode_nxdomain:
break;
case rcode_formaterror:
- adns__warn(ads,serv,"server cannot understand our query (Format Error)");
- adns__query_fail(ads,qu,adns_s_serverfaulty);
+ adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)");
+ adns__query_fail(qu,adns_s_serverfaulty);
return;
case rcode_servfail:
- adns__query_fail(ads,qu,adns_s_servfail);
+ adns__query_fail(qu,adns_s_servfail);
return;
case rcode_notimp:
- adns__warn(ads,serv,"server claims not to implement our query");
- adns__query_fail(ads,qu,adns_s_notimplemented);
+ adns__warn(ads,serv,qu,"server claims not to implement our query");
+ adns__query_fail(qu,adns_s_notimplemented);
return;
case rcode_refused:
- adns__warn(ads,serv,"server refused our query");
- adns__query_fail(ads,qu,adns_s_refused);
+ adns__warn(ads,serv,qu,"server refused our query");
+ adns__query_fail(qu,adns_s_refused);
return;
default:
- adns__warn(ads,serv,"server gave unknown response code %d",rcode);
- adns__query_fail(ads,qu,adns_s_reasonunknown);
+ adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
+ adns__query_fail(qu,adns_s_reasonunknown);
return;
}
wantedrrs= 0;
for (rri= 0; rri<ancount; rri++) {
rrstart= cbyte;
- if (qu->cnameoff >= 0) {
- st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
- &rrtype,&rrclass,&rdlength,&rdstart,
- dgram,dglen,qu->cnameoff, &ownermatched);
- } else {
- st= adns__get_rr_temp(ads,qu,serv, dgram,dglen,&cbyte,
- &rrtype,&rrclass,&rdlength,&rdstart,
- qu->querymsg,qu->querylen,DNS_HDRSIZE, &ownermatched);
- }
- if (st) adns__query_fail(ads,qu,st);
+ st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
+ &rrtype,&rrclass,&rdlength,&rdstart,
+ &ownermatched);
+ if (st) adns__query_fail(qu,st);
if (rrtype == -1) goto x_truncated;
if (rrclass != DNS_CLASS_IN) {
- adns__diag(ads,serv,"ignoring answer RR with wrong class %d (expected IN=%d)",
+ adns__diag(ads,serv,qu,"ignoring answer RR with wrong class %d (expected IN=%d)",
rrclass,DNS_CLASS_IN);
continue;
}
if (!ownermatched) {
if (ads->iflags & adns_if_debug) {
- st= adns__get_domain_temp(ads,qu,serv, dgram,dglen,&rrstart,dglen, &ownerstart);
- if (st)
- adns__debug(ads,serv, "ignoring RR with an irrelevant owner"
- " whose format is bad, code %d",st);
- else if (ownerstart>=0)
- adns__debug(ads,serv, "ignoring RR with an irrelevant owner"
- " \"%s\"", qu->ans.buf+ownerstart);
- else
- adns__debug(ads,serv,"ignoring RR with an irrelevant truncated owner");
+ adns__debug(ads,serv,qu,"ignoring RR with an unexpected owner %s",
+ adns__diag_domain(ads,serv,qu, &qu->vb,qu->flags,
+ dgram,dglen,rrstart));
}
continue;
}
- if (qu->cnameoff<0 &&
- (qu->typei->type & adns__rrt_typemask) != adns_r_cname &&
- rrtype == adns_r_cname) { /* Ignore second and subsequent CNAMEs */
- st= adns__get_domain_perm(ads,qu,serv, dgram,dglen,
- &rdstart,rdstart+rdlength,&qu->cnameoff);
- if (st) { adns__query_fail(ads,qu,st); return; }
- if (qu->cnameoff==-1) goto x_truncated;
- /* If we find the answer section truncated after this point we restart
- * the query at the CNAME; if beforehand then we obviously have to use
- * TCP. If there is no truncation we can use the whole answer if
- * it contains the relevant info.
- */
+ if (rrtype == adns_r_cname &&
+ (qu->typei->type & adns__rrt_typemask) != adns_r_cname) {
+ if (!qu->cname_dgram) { /* Ignore second and subsequent CNAMEs */
+ qu->cname_dgram= adns__alloc_mine(qu,dglen);
+ if (!qu->cname_dgram) return;
+ qu->cname_begin= rdstart;
+ qu->cname_dglen= dglen;
+ st= adns__parse_domain(ads,serv,qu, &qu->vb,qu->flags,
+ dgram,dglen, &rdstart,rdstart+rdlength);
+ if (!qu->vb.used) goto x_truncated;
+ if (st) { adns__query_fail(qu,st); return; }
+ l= strlen(qu->vb.buf)+1;
+ qu->answer->cname= adns__alloc_interim(qu,l);
+ if (!qu->answer->cname) return;
+ memcpy(qu->answer->cname,qu->vb.buf,l);
+ /* If we find the answer section truncated after this point we restart
+ * the query at the CNAME; if beforehand then we obviously have to use
+ * TCP. If there is no truncation we can use the whole answer if
+ * it contains the relevant info.
+ */
+ } else {
+ adns__debug(ads,serv,qu,"ignoring duplicate CNAME (%s, as well as %s)",
+ adns__diag_domain(ads,serv,qu, &qu->vb,qu->flags,
+ dgram,dglen,rdstart),
+ qu->answer->cname);
+ }
} else if (rrtype == (qu->typei->type & adns__rrt_typemask)) {
wantedrrs++;
} else {
- adns__debug(ads,serv,"ignoring answer RR with irrelevant type %d",rrtype);
+ adns__debug(ads,serv,qu,"ignoring answer RR with irrelevant type %d",rrtype);
}
}
/* Oops, NODATA or NXDOMAIN or perhaps a referral (which would be a problem) */
if (rcode == rcode_nxdomain) {
- adns__query_finish(ads,qu,adns_s_nxdomain);
+ adns__query_fail(qu,adns_s_nxdomain);
return;
}
foundsoa= 0; foundns= 0;
for (rri= 0; rri<nscount; rri++) {
rrstart= cbyte;
- st= adns__get_rr_temp(ads,qu,serv, dgram,dglen,&cbyte,
- &rrtype,&rrclass, &rdlength,&rdstart, 0,0,0,0);
- if (st) { adns__query_fail(ads,qu,st); return; }
+ st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
+ &rrtype,&rrclass,&rdlength,&rdstart, 0);
+ if (st) { adns__query_fail(qu,st); return; }
if (rrtype==-1) goto x_truncated;
if (rrclass != DNS_CLASS_IN) {
- adns__diag(ads,serv,"ignoring authority RR with wrong class %d (expected IN=%d)",
+ adns__diag(ads,serv,qu,
+ "ignoring authority RR with wrong class %d (expected IN=%d)",
rrclass,DNS_CLASS_IN);
continue;
}
if (foundsoa || !foundns) {
/* Aha ! A NODATA response, good. */
- adns__query_finish(ads,qu,adns_s_nodata);
+ adns__query_fail(qu,adns_s_nodata);
return;
}
/* Now what ? No relevant answers, no SOA, and at least some NS's.
* Looks like a referral. Just one last chance ... if we came across
- * a CNAME then perhaps we should do our own CNAME lookup.
+ * a CNAME in this datagram then we should probably do our own CNAME
+ * lookup now in the hope that we won't get a referral again.
*/
- if (qu->cnameoff != -1) { cname_recurse(ads,qu,0); return; }
+ if (qu->cname_dgram == dgram) { cname_recurse(qu,0); return; }
/* Bloody hell, I thought we asked for recursion ? */
+ if (flg_rd) {
+ adns__diag(ads,serv,qu,"server thinks we didn't ask for recursive lookup");
+ }
if (!flg_ra) {
- adns__diag(ads,serv,"server is not willing to do recursive lookups for us");
- adns__query_fail(ads,qu,adns_s_norecurse);
- return;
+ adns__diag(ads,serv,qu,"server is not willing to do recursive lookups for us");
+ adns__query_fail(qu,adns_s_norecurse);
+ } else {
+ adns__diag(ads,serv,qu,"server claims to do recursion, but gave us a referral");
+ adns__query_fail(qu,adns_s_serverfaulty);
}
- adns__diag(ads,serv,"server claims to do recursion, but gave us a referral");
- adns__query_fail(ads,qu,adns_s_serverfaulty);
return;
}
/* Now, we have some RRs which we wanted. */
- qu->rrsoff= adns__vbuf_malloc(&qu->ans,qu->typei->rrsz*wantedrrs);
- if (qu->rrsoff == -1) adns__query_fail(ads,qu,adns_s_nolocalmem);
+ qu->answer->rrs.untyped= adns__alloc_interim(qu,qu->typei->rrsz*wantedrrs);
+ if (!qu->answer->rrs.untyped) return;
cbyte= anstart;
- currentrrs= 0;
arstart= -1;
for (rri=0; rri<ancount; rri++) {
- st= adns__get_rr_temp(ads,qu,serv, dgram,dglen,&cbyte,
- &rrtype,&rrclass, &rdlength,&rdstart, 0,0,0,0);
+ st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
+ &rrtype,&rrclass,&rdlength,&rdstart,
+ &ownermatched);
assert(!st); assert(rrtype != -1);
if (rrclass != DNS_CLASS_IN ||
- rrtype != (qu->typei->type & adns__rrt_typemask))
+ rrtype != (qu->typei->type & adns__rrt_typemask) ||
+ !ownermatched)
continue;
- assert(currentrrs<wantedrrs);
- st= qu->typei->get_fn(ads,qu,serv, dgram,dglen, &rdstart,rdstart+rdlength,
- nsstart,arcount,&arstart, qu->rrsoff,¤trrs);
- if (st) { adns__query_fail(ads,qu,st); return; }
- if (currentrrs==-1) goto x_truncated;
+ assert(qu->answer->nrrs<wantedrrs);
+ st= qu->typei->parse(qu,serv,
+ dgram,dglen, rdstart,rdstart+rdlength,
+ qu->answer->rrs.bytes+qu->answer->nrrs*qu->typei->rrsz);
+ if (st) { adns__query_fail(qu,st); return; }
+ if (rdstart==-1) goto x_truncated;
}
/* This may have generated some child queries ... */
return;
}
- adns__query_finish(ads,qu,adns_s_ok);
+ adns__query_done(qu);
return;
-x_truncated:
+ x_truncated:
if (!flg_tc) {
- adns__diag(ads,serv,"server sent datagram which points outside itself");
- adns__query_fail(ads,qu,adns_s_serverfaulty);
+ adns__diag(ads,serv,qu,"server sent datagram which points outside itself");
+ adns__query_fail(qu,adns_s_serverfaulty);
return;
}
- if (qu->cnameoff != -1) { cname_recurse(ads,qu,adns_qf_usevc); return; }
- qu->cnameoff= -1;
- qu->rrsoff= -1;
- ans= (adns_answer*)qu->ans.buf;
- ans->nrrs= 0;
- qu->ans.used= sizeof(adns_answer);
+ if (qu->cname_dgram) { cname_recurse(qu,adns_qf_usevc); return; }
+ adns__reset_cnameonly(qu);
qu->flags |= adns_qf_usevc;
- adns__query_udp(ads,qu,now);
+ adns__query_udp(qu,now);
}
~ianmdlvl / adns.git / blobdiff