[adns] / src / reply.c

/*
 * 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) {
  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_rd, flg_tc, opcode;
  int rrtype, rrclass, rdlength, rdstart, ownermatched, ownerstart;
  int anstart, nsstart, arstart;
  int currentrrs;
  adns_query qu, nqu;
  dns_rcode rcode;
  adns_status st;
  
  if (dglen<DNS_HDRSIZE) {
    adns__diag(ads,serv,"received datagram too short for message header (%d)",dglen);
    return;
  }
  GET_W(cbyte,id);
  GET_B(cbyte,f1);
  GET_B(cbyte,f2);
  GET_W(cbyte,qdcount);
  GET_W(cbyte,ancount);
  GET_W(cbyte,nscount);
  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 (flg_qr) {
    adns__diag(ads,serv,"server sent us a query, not a response");
    return;
  }
  if (opcode) {
    adns__diag(ads,serv,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
    return;
  }
  if (!qdcount) {
    adns__diag(ads,serv,"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",
	       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))
      continue;
    break;
  }
  assert(qu->cnameoff == -1);
  anstart= qu->querylen;
  if (!qu) {
    adns__debug(ads,serv,"reply not found (id=%02x)",id);
    return;
  }

  LIST_UNLINK(ads->timew,qu);
  /* We're definitely going to do something with this query now */
  
  switch (rcode) {
  case rcode_noerror:
  case rcode_nxdomain:
    break;
  case rcode_formaterror:
    adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)");
    adns__query_fail(ads,qu,adns_s_serverfaulty);
    return;
  case rcode_servfail:
    adns__query_fail(ads,qu,adns_s_servfail);
    return;
  case rcode_notimp:
    adns__warn(ads,serv,qu,"server claims not to implement our query");
    adns__query_fail(ads,qu,adns_s_notimplemented);
    return;
  case rcode_refused:
    adns__warn(ads,serv,qu,"server refused our query");
    adns__query_fail(ads,qu,adns_s_refused);
    return;
  default:
    adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
    adns__query_fail(ads,qu,adns_s_reasonunknown);
    return;
  }

  /* Now, take a look at the answer section, and see if it is complete.
   * If it has any CNAMEs we stuff them in the answer.
   */
  wantedrrs= 0;
  for (rri= 0; rri<ancount; rri++) {
    rrstart= cbyte;
    if (qu->cname_dgram >= 0) {
      st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
		       &rrtype,&rrclass,&rdlength,&rdstart,
		       qu->cname_dgram,qu->cname_dglen,qu->cname_begin, &ownermatched);
    } else {
      st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
		       &rrtype,&rrclass,&rdlength,&rdstart,
		       qu->querymsg,qu->querylen,DNS_HDRSIZE, &ownermatched);
    }
    if (st) adns__query_fail(ads,qu,st);
    if (rrtype == -1) goto x_truncated;

    if (rrclass != DNS_CLASS_IN) {
      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) {
	adns__debug(ads,serv,qu,"ignoring RR with an unexpected owner %s",
		    adns__diag_domain(ads,serv,&qu->vb,qu->flags,
				      dgram,dglen,rrstart,dglen));
      }
      continue;
    }
    if (rrtype == adns_r_cname &&
	(qu->typei->type & adns__rrt_typemask) != adns_r_cname) {
      if (!qu->cname_str) { /* Ignore second and subsequent CNAMEs */
	qu->cname_begin= rdstart;
	qu->cname_dgram= dgram;
	qu->cname_dglen= dglen;
	st= adns__parse_domain(ads,serv,&qu->vb,qu->flags,
			       dgram,dglen, &rdstart,rdstart+rdlength);
	if (!vb.used) goto x_truncated;
	if (st) { adns__query_fail(ads,qu,st); return; }
	qu->answer->cname= adns__savestring(qu);
	if (!qu->answer->cname) return;
	/* 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->vb,qu->flags,
				      dgram,dglen, rdstart,rdstart+rdlength),
		    qu->cname_str);
      }
    } else if (rrtype == (qu->typei->type & adns__rrt_typemask)) {
      wantedrrs++;
    } else {
      adns__debug(ads,serv,qu,"ignoring answer RR with irrelevant type %d",rrtype);
    }
  }

  /* If we got here then the answer section is intact. */
  nsstart= cbyte;

  if (!wantedrrs) {
    /* 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);
      return;
    }

    /* RFC2308: NODATA has _either_ a SOA _or_ _no_ NS records in authority section */
    foundsoa= 0; foundns= 0;
    for (rri= 0; rri<nscount; rri++) {
      rrstart= cbyte;
      st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
		       &rrtype,&rrclass,&rdlength,&rdstart,
		       0,0,0,0);
      if (st) { adns__query_fail(ads,qu,st); return; }
      if (rrtype==-1) goto x_truncated;
      if (rrclass != DNS_CLASS_IN) {
	adns__diag(ads,serv,qu,
		   "ignoring authority RR with wrong class %d (expected IN=%d)",
		   rrclass,DNS_CLASS_IN);
	continue;
      }
      if (rrtype == adns_r_soa_raw) { foundsoa= 1; break; }
      else if (rrtype == adns_r_ns_raw) { foundns= 1; }
    }

    if (foundsoa || !foundns) {
      /* Aha !  A NODATA response, good. */
      adns__query_finish(ads,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 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->cname_dgram == dgram) { cname_recurse(ads,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,qu,"server is not willing to do recursive lookups for us");
      adns__query_fail(ads,qu,adns_s_norecurse);
    } else {
      adns__diag(ads,serv,qu,"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->ans->rrs= adns__alloc_interim(qu,qu->typei->rrsz*wantedrrs);
  if (!qu->ans->rrs) return;

  cbyte= anstart;
  arstart= -1;
  for (rri=0; rri<ancount; rri++) {
    if (qu->cname_dgram >= 0) {
      st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
		       &rrtype,&rrclass,&rdlength,&rdstart,
		       qu->cname_dgram,qu->cname_dglen,qu->cname_begin, &ownermatched);
    } else {
      st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
		       &rrtype,&rrclass,&rdlength,&rdstart,
		       qu->querymsg,qu->querylen,DNS_HDRSIZE, &ownermatched);
    }
    assert(!st); assert(rrtype != -1);
    if (rrclass != DNS_CLASS_IN ||
	rrtype != (qu->typei->type & adns__rrt_typemask) ||
	!ownermatched)
      continue;
    assert(qu->ans->nrrs<wantedrrs);
    st= qu->typei->parse(ads,qu,serv,
			 dgram,dglen, &rdstart,rdstart+rdlength,
			 qu->ans->rrs.bytes+qu->ans->nrrs*quj->typei->rrsz);
    if (st) { adns__query_fail(ads,qu,st); return; }
    if (rdstart==-1) goto x_truncated;
  }

  /* This may have generated some child queries ... */
  if (qu->children.head) {
    qu->state= query_child;
    LIST_LINK_TAIL(ads->childw,qu);
    return;
  }

  adns__query_finish(ads,qu,adns_s_ok);
  return;

 x_truncated:
  if (!flg_tc) {
    adns__diag(ads,serv,qu,"server sent datagram which points outside itself");
    adns__query_fail(ads,qu,adns_s_serverfaulty);
    return;
  }
  if (qu->cname_dgram) { cname_recurse(ads,qu,adns_qf_usevc); return; }
  adns__reset_cnameonly(ads,qu);
  qu->flags |= adns_qf_usevc;
  adns__query_udp(ads,qu,now);
}
Commit	Line	Data
98db6da3	1	/*
	2	* reply.c
	3	* - main handling and parsing routine for received datagrams
	4	*/
	5	/*
	6	* This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License as published by
	10	* the Free Software Foundation; either version 2, or (at your option)
	11	* any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software Foundation,
	20	* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
	21	*/
d05cc330	22
	23	#include "internal.h"
	24
5c596e4d	25	static void cname_recurse(adns_state ads, adns_query qu, adns_queryflags xflags) {
5c596e4d	26	abort(); /* FIXME */
54ed1d64	27	}
54ed1d64	28
5c596e4d	29	void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
	30	int serv, struct timeval now) {
	31	int cbyte, rrstart, wantedrrs, rri, foundsoa, foundns;
7f702335	32	int id, f1, f2, qdcount, ancount, nscount, arcount, flg_ra, flg_rd, flg_tc, opcode;
5c596e4d	33	int rrtype, rrclass, rdlength, rdstart, ownermatched, ownerstart;
	34	int anstart, nsstart, arstart;
	35	int currentrrs;
	36	adns_query qu, nqu;
	37	dns_rcode rcode;
54ed1d64	38	adns_status st;
168e26fe	39
5c596e4d	40	if (dglen<DNS_HDRSIZE) {
5c596e4d	41	adns__diag(ads,serv,"received datagram too short for message header (%d)",dglen);
168e26fe	42	return;
168e26fe	43	}
54ed1d64	44	GET_W(cbyte,id);
	45	GET_B(cbyte,f1);
	46	GET_B(cbyte,f2);
	47	GET_W(cbyte,qdcount);
	48	GET_W(cbyte,ancount);
	49	GET_W(cbyte,nscount);
	50	GET_W(cbyte,arcount);
5c596e4d	51	assert(cbyte == DNS_HDRSIZE);
168e26fe	52
7f702335	53	flg_qr= f1&0x80;
7f702335	54	opcode= (f1&0x78)>>3;
5c596e4d	55	flg_tc= f1&0x20;
7f702335	56	flg_rd= f1&0x01;
8312a1c2	57	flg_ra= f2&0x80;
7f702335	58	rcode= (f1&0x0f);
8312a1c2	59
7f702335	60	if (flg_qr) {
168e26fe	61	adns__diag(ads,serv,"server sent us a query, not a response");
	62	return;
	63	}
7f702335	64	if (opcode) {
7f702335	65	adns__diag(ads,serv,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
168e26fe	66	return;
	67	}
	68	if (!qdcount) {
	69	adns__diag(ads,serv,"server sent reply without quoting our question");
	70	return;
	71	} else if (qdcount>1) {
	72	adns__diag(ads,serv,"server claimed to answer %d questions with one message",
	73	qdcount);
	74	return;
	75	}
5c596e4d	76	for (qu= ads->timew.head; qu; qu= nqu) {
168e26fe	77	nqu= qu->next;
168e26fe	78	if (qu->id != id) continue;
5c596e4d	79	if (dglen < qu->querylen) continue;
5c596e4d	80	if (memcmp(qu->querymsg+DNS_HDRSIZE,dgram+DNS_HDRSIZE,qu->querylen-DNS_HDRSIZE))
54ed1d64	81	continue;
168e26fe	82	break;
168e26fe	83	}
5c596e4d	84	assert(qu->cnameoff == -1);
54ed1d64	85	anstart= qu->querylen;
168e26fe	86	if (!qu) {
	87	adns__debug(ads,serv,"reply not found (id=%02x)",id);
	88	return;
	89	}
5c596e4d	90
	91	LIST_UNLINK(ads->timew,qu);
	92	/* We're definitely going to do something with this query now */
	93
54ed1d64	94	switch (rcode) {
	95	case rcode_noerror:
	96	case rcode_nxdomain:
168e26fe	97	break;
54ed1d64	98	case rcode_formaterror:
7f702335	99	adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)");
168e26fe	100	adns__query_fail(ads,qu,adns_s_serverfaulty);
168e26fe	101	return;
5c596e4d	102	case rcode_servfail:
5c596e4d	103	adns__query_fail(ads,qu,adns_s_servfail);
168e26fe	104	return;
54ed1d64	105	case rcode_notimp:
7f702335	106	adns__warn(ads,serv,qu,"server claims not to implement our query");
54ed1d64	107	adns__query_fail(ads,qu,adns_s_notimplemented);
	108	return;
	109	case rcode_refused:
7f702335	110	adns__warn(ads,serv,qu,"server refused our query");
54ed1d64	111	adns__query_fail(ads,qu,adns_s_refused);
	112	return;
	113	default:
7f702335	114	adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
54ed1d64	115	adns__query_fail(ads,qu,adns_s_reasonunknown);
	116	return;
	117	}
	118
	119	/* Now, take a look at the answer section, and see if it is complete.
	120	* If it has any CNAMEs we stuff them in the answer.
	121	*/
	122	wantedrrs= 0;
	123	for (rri= 0; rri<ancount; rri++) {
	124	rrstart= cbyte;
7f702335	125	if (qu->cname_dgram >= 0) {
403fa0e0	126	st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
403fa0e0	127	&rrtype,&rrclass,&rdlength,&rdstart,
7f702335	128	qu->cname_dgram,qu->cname_dglen,qu->cname_begin, &ownermatched);
8312a1c2	129	} else {
7f702335	130	st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
	131	&rrtype,&rrclass,&rdlength,&rdstart,
	132	qu->querymsg,qu->querylen,DNS_HDRSIZE, &ownermatched);
8312a1c2	133	}
54ed1d64	134	if (st) adns__query_fail(ads,qu,st);
8312a1c2	135	if (rrtype == -1) goto x_truncated;
8312a1c2	136
54ed1d64	137	if (rrclass != DNS_CLASS_IN) {
7f702335	138	adns__diag(ads,serv,qu,"ignoring answer RR with wrong class %d (expected IN=%d)",
54ed1d64	139	rrclass,DNS_CLASS_IN);
	140	continue;
	141	}
8312a1c2	142	if (!ownermatched) {
5c596e4d	143	if (ads->iflags & adns_if_debug) {
7f702335	144	adns__debug(ads,serv,qu,"ignoring RR with an unexpected owner %s",
965c9782	145	adns__diag_domain(ads,serv,&qu->vb,qu->flags,
7f702335	146	dgram,dglen,rrstart,dglen));
8312a1c2	147	}
54ed1d64	148	continue;
54ed1d64	149	}
7f702335	150	if (rrtype == adns_r_cname &&
	151	(qu->typei->type & adns__rrt_typemask) != adns_r_cname) {
	152	if (!qu->cname_str) { /* Ignore second and subsequent CNAMEs */
	153	qu->cname_begin= rdstart;
	154	qu->cname_dgram= dgram;
	155	qu->cname_dglen= dglen;
965c9782	156	st= adns__parse_domain(ads,serv,&qu->vb,qu->flags,
7f702335	157	dgram,dglen, &rdstart,rdstart+rdlength);
	158	if (!vb.used) goto x_truncated;
	159	if (st) { adns__query_fail(ads,qu,st); return; }
965c9782	160	qu->answer->cname= adns__savestring(qu);
965c9782	161	if (!qu->answer->cname) return;
7f702335	162	/* If we find the answer section truncated after this point we restart
	163	* the query at the CNAME; if beforehand then we obviously have to use
	164	* TCP. If there is no truncation we can use the whole answer if
	165	* it contains the relevant info.
	166	*/
	167	} else {
	168	adns__debug(ads,serv,qu,"ignoring duplicate CNAME (%s, as well as %s)",
965c9782	169	adns__diag_domain(ads,serv,&qu->vb,qu->flags,
7f702335	170	dgram,dglen, rdstart,rdstart+rdlength),
	171	qu->cname_str);
	172	}
5c596e4d	173	} else if (rrtype == (qu->typei->type & adns__rrt_typemask)) {
54ed1d64	174	wantedrrs++;
54ed1d64	175	} else {
7f702335	176	adns__debug(ads,serv,qu,"ignoring answer RR with irrelevant type %d",rrtype);
54ed1d64	177	}
	178	}
	179
	180	/* If we got here then the answer section is intact. */
	181	nsstart= cbyte;
	182
	183	if (!wantedrrs) {
	184	/* Oops, NODATA or NXDOMAIN or perhaps a referral (which would be a problem) */
	185
	186	if (rcode == rcode_nxdomain) {
8312a1c2	187	adns__query_finish(ads,qu,adns_s_nxdomain);
54ed1d64	188	return;
	189	}
	190
	191	/* RFC2308: NODATA has _either_ a SOA _or_ _no_ NS records in authority section */
8312a1c2	192	foundsoa= 0; foundns= 0;
54ed1d64	193	for (rri= 0; rri<nscount; rri++) {
8312a1c2	194	rrstart= cbyte;
7f702335	195	st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
	196	&rrtype,&rrclass,&rdlength,&rdstart,
	197	0,0,0,0);
5c596e4d	198	if (st) { adns__query_fail(ads,qu,st); return; }
8312a1c2	199	if (rrtype==-1) goto x_truncated;
8312a1c2	200	if (rrclass != DNS_CLASS_IN) {
7f702335	201	adns__diag(ads,serv,qu,
7f702335	202	"ignoring authority RR with wrong class %d (expected IN=%d)",
8312a1c2	203	rrclass,DNS_CLASS_IN);
	204	continue;
	205	}
	206	if (rrtype == adns_r_soa_raw) { foundsoa= 1; break; }
	207	else if (rrtype == adns_r_ns_raw) { foundns= 1; }
54ed1d64	208	}
8312a1c2	209
	210	if (foundsoa \|\| !foundns) {
	211	/* Aha ! A NODATA response, good. */
	212	adns__query_finish(ads,qu,adns_s_nodata);
	213	return;
	214	}
	215
	216	/* Now what ? No relevant answers, no SOA, and at least some NS's.
	217	* Looks like a referral. Just one last chance ... if we came across
7f702335	218	* a CNAME in this datagram then we should probably do our own CNAME
7f702335	219	* lookup now in the hope that we won't get a referral again.
8312a1c2	220	*/
7f702335	221	if (qu->cname_dgram == dgram) { cname_recurse(ads,qu,0); return; }
8312a1c2	222
8312a1c2	223	/* Bloody hell, I thought we asked for recursion ? */
7f702335	224	if (flg_rd) {
	225	adns__diag(ads,serv,qu,"server thinks we didn't ask for recursive lookup");
	226	}
8312a1c2	227	if (!flg_ra) {
7f702335	228	adns__diag(ads,serv,qu,"server is not willing to do recursive lookups for us");
8312a1c2	229	adns__query_fail(ads,qu,adns_s_norecurse);
7f702335	230	} else {
	231	adns__diag(ads,serv,qu,"server claims to do recursion, but gave us a referral");
	232	adns__query_fail(ads,qu,adns_s_serverfaulty);
8312a1c2	233	}
54ed1d64	234	return;
	235	}
	236
8312a1c2	237	/* Now, we have some RRs which we wanted. */
54ed1d64	238
965c9782	239	qu->ans->rrs= adns__alloc_interim(qu,qu->typei->rrsz*wantedrrs);
965c9782	240	if (!qu->ans->rrs) return;
5c596e4d	241
5c596e4d	242	cbyte= anstart;
5c596e4d	243	arstart= -1;
5c596e4d	244	for (rri=0; rri<ancount; rri++) {
7f702335	245	if (qu->cname_dgram >= 0) {
	246	st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
	247	&rrtype,&rrclass,&rdlength,&rdstart,
	248	qu->cname_dgram,qu->cname_dglen,qu->cname_begin, &ownermatched);
	249	} else {
	250	st= adns__findrr(ads,serv, dgram,dglen,&cbyte,
	251	&rrtype,&rrclass,&rdlength,&rdstart,
	252	qu->querymsg,qu->querylen,DNS_HDRSIZE, &ownermatched);
	253	}
5c596e4d	254	assert(!st); assert(rrtype != -1);
5c596e4d	255	if (rrclass != DNS_CLASS_IN \|\|
7f702335	256	rrtype != (qu->typei->type & adns__rrt_typemask) \|\|
7f702335	257	!ownermatched)
5c596e4d	258	continue;
965c9782	259	assert(qu->ans->nrrs<wantedrrs);
965c9782	260	st= qu->typei->parse(ads,qu,serv,
7f702335	261	dgram,dglen, &rdstart,rdstart+rdlength,
965c9782	262	qu->ans->rrs.bytes+qu->ans->nrrs*quj->typei->rrsz);
5c596e4d	263	if (st) { adns__query_fail(ads,qu,st); return; }
7f702335	264	if (rdstart==-1) goto x_truncated;
5c596e4d	265	}
54ed1d64	266
5c596e4d	267	/* This may have generated some child queries ... */
	268	if (qu->children.head) {
	269	qu->state= query_child;
	270	LIST_LINK_TAIL(ads->childw,qu);
	271	return;
54ed1d64	272	}
168e26fe	273
5c596e4d	274	adns__query_finish(ads,qu,adns_s_ok);
5c596e4d	275	return;
8312a1c2	276
98db6da3	277	x_truncated:
5c596e4d	278	if (!flg_tc) {
7f702335	279	adns__diag(ads,serv,qu,"server sent datagram which points outside itself");
5c596e4d	280	adns__query_fail(ads,qu,adns_s_serverfaulty);
	281	return;
	282	}
7f702335	283	if (qu->cname_dgram) { cname_recurse(ads,qu,adns_qf_usevc); return; }
965c9782	284	adns__reset_cnameonly(ads,qu);
5c596e4d	285	qu->flags \|= adns_qf_usevc;
	286	adns__query_udp(ads,qu,now);
	287	}