[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_query qu, adns_queryflags xflags) {
  adns__diag(qu->ads,-1,qu,"cname following not implemented fixme");
  adns__query_fail(qu,adns_s_notimplemented);
}
    
void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
		     int serv, struct timeval now) {
  int cbyte, rrstart, wantedrrs, rri, foundsoa, foundns, cname_here;
  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;
  adns_query qu, nqu;
  dns_rcode rcode;
  adns_status st;
  vbuf tempvb;
  
  if (dglen<DNS_HDRSIZE) {
    adns__diag(ads,serv,0,"received datagram too short for message header (%d)",dglen);
    return;
  }
  cbyte= 0;
  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= (f2&0x0f);

  cname_here= 0;
  
  if (!flg_qr) {
    adns__diag(ads,serv,0,"server sent us a query, not a response");
    return;
  }
  if (opcode) {
    adns__diag(ads,serv,0,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
    return;
  }
  if (!qdcount) {
    adns__diag(ads,serv,0,"server sent reply without quoting our question");
    return;
  } else if (qdcount>1) {
    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->query_dglen) continue;
    if (memcmp(qu->query_dgram+DNS_HDRSIZE,
	       dgram+DNS_HDRSIZE,
	       qu->query_dglen-DNS_HDRSIZE))
      continue;
    break;
  }
  if (!qu) {
    if (ads->iflags & adns_if_debug) {
      adns__vbuf_init(&tempvb);
      adns__debug(ads,serv,0,"reply not found, id %02x, query owner %s",
		  id, adns__diag_domain(ads,serv,0,&tempvb,adns_qf_anyquote,
					dgram,dglen,DNS_HDRSIZE));
      adns__vbuf_free(&tempvb);
    }
    return;
  }
  anstart= qu->query_dglen;

  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(qu,adns_s_serverfaulty);
    return;
  case rcode_servfail:
    adns__query_fail(qu,adns_s_servfail);
    return;
  case rcode_notimp:
    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,qu,"server refused our query");
    adns__query_fail(qu,adns_s_refused);
    return;
  default:
    adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
    adns__query_fail(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;
  cbyte= anstart;
  for (rri= 0; rri<ancount; rri++) {
    rrstart= cbyte;
    st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
		     &rrtype,&rrclass,&rdlength,&rdstart,
		     &ownermatched);
    if (st) { adns__query_fail(qu,st); return; }
    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, &qu->vb,qu->flags,
				      dgram,dglen,rrstart));
      }
      continue;
    }
    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);
	cname_here= 1;
	/* 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,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_fail(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(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,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_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 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 (cname_here) { 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,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);
    }
    return;
  }

  /* Now, we have some RRs which we wanted. */

  qu->answer->rrs.untyped= adns__alloc_interim(qu,qu->typei->rrsz*wantedrrs);
  if (!qu->answer->rrs.untyped) return;

  cbyte= anstart;
  arstart= -1;
  for (rri=0; rri<ancount; rri++) {
    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) ||
	!ownermatched)
      continue;
    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;
    qu->answer->nrrs++;
  }

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

  adns__query_done(qu);
  return;

 x_truncated:
  if (!flg_tc) {
    adns__diag(ads,serv,qu,"server sent datagram which points outside itself");
    adns__query_fail(qu,adns_s_serverfaulty);
    return;
  }
  if (qu->cname_dgram) { cname_recurse(qu,adns_qf_usevc); return; }
  adns__reset_cnameonly(qu);
  qu->flags |= adns_qf_usevc;
  adns__query_udp(qu,now);
}
Commit	Line	Data
e576be50	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	*/
4353a5c4	22
	23	#include "internal.h"
	24
3955725c	25	static void cname_recurse(adns_query qu, adns_queryflags xflags) {
ffbda80c	26	adns__diag(qu->ads,-1,qu,"cname following not implemented fixme");
ffbda80c	27	adns__query_fail(qu,adns_s_notimplemented);
b9de380c	28	}
b9de380c	29
98a3f706	30	void adns__procdgram(adns_state ads, const byte *dgram, int dglen,
98a3f706	31	int serv, struct timeval now) {
86e7b8d9	32	int cbyte, rrstart, wantedrrs, rri, foundsoa, foundns, cname_here;
3955725c	33	int id, f1, f2, qdcount, ancount, nscount, arcount;
	34	int flg_ra, flg_rd, flg_tc, flg_qr, opcode;
	35	int rrtype, rrclass, rdlength, rdstart, ownermatched, l;
98a3f706	36	int anstart, nsstart, arstart;
98a3f706	37	adns_query qu, nqu;
98a3f706	38	dns_rcode rcode;
b9de380c	39	adns_status st;
86e7b8d9	40	vbuf tempvb;
ec477b9e	41
98a3f706	42	if (dglen<DNS_HDRSIZE) {
3955725c	43	adns__diag(ads,serv,0,"received datagram too short for message header (%d)",dglen);
ec477b9e	44	return;
ec477b9e	45	}
9557e604	46	cbyte= 0;
b9de380c	47	GET_W(cbyte,id);
	48	GET_B(cbyte,f1);
	49	GET_B(cbyte,f2);
	50	GET_W(cbyte,qdcount);
	51	GET_W(cbyte,ancount);
	52	GET_W(cbyte,nscount);
	53	GET_W(cbyte,arcount);
98a3f706	54	assert(cbyte == DNS_HDRSIZE);
ec477b9e	55
31144a72	56	flg_qr= f1&0x80;
31144a72	57	opcode= (f1&0x78)>>3;
98a3f706	58	flg_tc= f1&0x20;
31144a72	59	flg_rd= f1&0x01;
0ba0614a	60	flg_ra= f2&0x80;
86e7b8d9	61	rcode= (f2&0x0f);
0ba0614a	62
86e7b8d9	63	cname_here= 0;
86e7b8d9	64
9557e604	65	if (!flg_qr) {
3955725c	66	adns__diag(ads,serv,0,"server sent us a query, not a response");
ec477b9e	67	return;
ec477b9e	68	}
31144a72	69	if (opcode) {
3955725c	70	adns__diag(ads,serv,0,"server sent us unknown opcode %d (wanted 0=QUERY)",opcode);
ec477b9e	71	return;
	72	}
	73	if (!qdcount) {
3955725c	74	adns__diag(ads,serv,0,"server sent reply without quoting our question");
ec477b9e	75	return;
ec477b9e	76	} else if (qdcount>1) {
3955725c	77	adns__diag(ads,serv,0,"server claimed to answer %d questions with one message",
ec477b9e	78	qdcount);
	79	return;
	80	}
98a3f706	81	for (qu= ads->timew.head; qu; qu= nqu) {
ec477b9e	82	nqu= qu->next;
ec477b9e	83	if (qu->id != id) continue;
3955725c	84	if (dglen < qu->query_dglen) continue;
	85	if (memcmp(qu->query_dgram+DNS_HDRSIZE,
	86	dgram+DNS_HDRSIZE,
	87	qu->query_dglen-DNS_HDRSIZE))
b9de380c	88	continue;
ec477b9e	89	break;
	90	}
	91	if (!qu) {
86e7b8d9	92	if (ads->iflags & adns_if_debug) {
	93	adns__vbuf_init(&tempvb);
	94	adns__debug(ads,serv,0,"reply not found, id %02x, query owner %s",
	95	id, adns__diag_domain(ads,serv,0,&tempvb,adns_qf_anyquote,
	96	dgram,dglen,DNS_HDRSIZE));
	97	adns__vbuf_free(&tempvb);
	98	}
ec477b9e	99	return;
ec477b9e	100	}
86e7b8d9	101	anstart= qu->query_dglen;
98a3f706	102
	103	LIST_UNLINK(ads->timew,qu);
	104	/* We're definitely going to do something with this query now */
	105
b9de380c	106	switch (rcode) {
	107	case rcode_noerror:
	108	case rcode_nxdomain:
ec477b9e	109	break;
b9de380c	110	case rcode_formaterror:
31144a72	111	adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)");
3955725c	112	adns__query_fail(qu,adns_s_serverfaulty);
ec477b9e	113	return;
98a3f706	114	case rcode_servfail:
3955725c	115	adns__query_fail(qu,adns_s_servfail);
ec477b9e	116	return;
b9de380c	117	case rcode_notimp:
31144a72	118	adns__warn(ads,serv,qu,"server claims not to implement our query");
3955725c	119	adns__query_fail(qu,adns_s_notimplemented);
b9de380c	120	return;
b9de380c	121	case rcode_refused:
31144a72	122	adns__warn(ads,serv,qu,"server refused our query");
3955725c	123	adns__query_fail(qu,adns_s_refused);
b9de380c	124	return;
b9de380c	125	default:
31144a72	126	adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode);
3955725c	127	adns__query_fail(qu,adns_s_reasonunknown);
b9de380c	128	return;
	129	}
	130
	131	/* Now, take a look at the answer section, and see if it is complete.
	132	* If it has any CNAMEs we stuff them in the answer.
	133	*/
	134	wantedrrs= 0;
86e7b8d9	135	cbyte= anstart;
b9de380c	136	for (rri= 0; rri<ancount; rri++) {
b9de380c	137	rrstart= cbyte;
3955725c	138	st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
	139	&rrtype,&rrclass,&rdlength,&rdstart,
	140	&ownermatched);
86e7b8d9	141	if (st) { adns__query_fail(qu,st); return; }
0ba0614a	142	if (rrtype == -1) goto x_truncated;
0ba0614a	143
b9de380c	144	if (rrclass != DNS_CLASS_IN) {
31144a72	145	adns__diag(ads,serv,qu,"ignoring answer RR with wrong class %d (expected IN=%d)",
b9de380c	146	rrclass,DNS_CLASS_IN);
	147	continue;
	148	}
0ba0614a	149	if (!ownermatched) {
98a3f706	150	if (ads->iflags & adns_if_debug) {
31144a72	151	adns__debug(ads,serv,qu,"ignoring RR with an unexpected owner %s",
3955725c	152	adns__diag_domain(ads,serv,qu, &qu->vb,qu->flags,
3955725c	153	dgram,dglen,rrstart));
0ba0614a	154	}
b9de380c	155	continue;
b9de380c	156	}
31144a72	157	if (rrtype == adns_r_cname &&
31144a72	158	(qu->typei->type & adns__rrt_typemask) != adns_r_cname) {
3955725c	159	if (!qu->cname_dgram) { /* Ignore second and subsequent CNAMEs */
	160	qu->cname_dgram= adns__alloc_mine(qu,dglen);
	161	if (!qu->cname_dgram) return;
31144a72	162	qu->cname_begin= rdstart;
31144a72	163	qu->cname_dglen= dglen;
3955725c	164	st= adns__parse_domain(ads,serv,qu, &qu->vb,qu->flags,
31144a72	165	dgram,dglen, &rdstart,rdstart+rdlength);
3955725c	166	if (!qu->vb.used) goto x_truncated;
	167	if (st) { adns__query_fail(qu,st); return; }
	168	l= strlen(qu->vb.buf)+1;
	169	qu->answer->cname= adns__alloc_interim(qu,l);
8e5b0abb	170	if (!qu->answer->cname) return;
3955725c	171	memcpy(qu->answer->cname,qu->vb.buf,l);
86e7b8d9	172	cname_here= 1;
31144a72	173	/* If we find the answer section truncated after this point we restart
	174	* the query at the CNAME; if beforehand then we obviously have to use
	175	* TCP. If there is no truncation we can use the whole answer if
	176	* it contains the relevant info.
	177	*/
	178	} else {
	179	adns__debug(ads,serv,qu,"ignoring duplicate CNAME (%s, as well as %s)",
3955725c	180	adns__diag_domain(ads,serv,qu, &qu->vb,qu->flags,
	181	dgram,dglen,rdstart),
	182	qu->answer->cname);
31144a72	183	}
98a3f706	184	} else if (rrtype == (qu->typei->type & adns__rrt_typemask)) {
b9de380c	185	wantedrrs++;
b9de380c	186	} else {
31144a72	187	adns__debug(ads,serv,qu,"ignoring answer RR with irrelevant type %d",rrtype);
b9de380c	188	}
	189	}
	190
	191	/* If we got here then the answer section is intact. */
	192	nsstart= cbyte;
	193
	194	if (!wantedrrs) {
	195	/* Oops, NODATA or NXDOMAIN or perhaps a referral (which would be a problem) */
	196
	197	if (rcode == rcode_nxdomain) {
3955725c	198	adns__query_fail(qu,adns_s_nxdomain);
b9de380c	199	return;
	200	}
	201
	202	/* RFC2308: NODATA has _either_ a SOA _or_ _no_ NS records in authority section */
0ba0614a	203	foundsoa= 0; foundns= 0;
b9de380c	204	for (rri= 0; rri<nscount; rri++) {
0ba0614a	205	rrstart= cbyte;
3955725c	206	st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
	207	&rrtype,&rrclass,&rdlength,&rdstart, 0);
	208	if (st) { adns__query_fail(qu,st); return; }
0ba0614a	209	if (rrtype==-1) goto x_truncated;
0ba0614a	210	if (rrclass != DNS_CLASS_IN) {
31144a72	211	adns__diag(ads,serv,qu,
31144a72	212	"ignoring authority RR with wrong class %d (expected IN=%d)",
0ba0614a	213	rrclass,DNS_CLASS_IN);
	214	continue;
	215	}
	216	if (rrtype == adns_r_soa_raw) { foundsoa= 1; break; }
	217	else if (rrtype == adns_r_ns_raw) { foundns= 1; }
b9de380c	218	}
0ba0614a	219
	220	if (foundsoa \|\| !foundns) {
	221	/* Aha ! A NODATA response, good. */
3955725c	222	adns__query_fail(qu,adns_s_nodata);
0ba0614a	223	return;
	224	}
	225
	226	/* Now what ? No relevant answers, no SOA, and at least some NS's.
	227	* Looks like a referral. Just one last chance ... if we came across
31144a72	228	* a CNAME in this datagram then we should probably do our own CNAME
31144a72	229	* lookup now in the hope that we won't get a referral again.
0ba0614a	230	*/
86e7b8d9	231	if (cname_here) { cname_recurse(qu,0); return; }
0ba0614a	232
0ba0614a	233	/* Bloody hell, I thought we asked for recursion ? */
31144a72	234	if (flg_rd) {
	235	adns__diag(ads,serv,qu,"server thinks we didn't ask for recursive lookup");
	236	}
0ba0614a	237	if (!flg_ra) {
31144a72	238	adns__diag(ads,serv,qu,"server is not willing to do recursive lookups for us");
3955725c	239	adns__query_fail(qu,adns_s_norecurse);
31144a72	240	} else {
31144a72	241	adns__diag(ads,serv,qu,"server claims to do recursion, but gave us a referral");
3955725c	242	adns__query_fail(qu,adns_s_serverfaulty);
0ba0614a	243	}
b9de380c	244	return;
	245	}
	246
0ba0614a	247	/* Now, we have some RRs which we wanted. */
b9de380c	248
3955725c	249	qu->answer->rrs.untyped= adns__alloc_interim(qu,qu->typei->rrsz*wantedrrs);
3955725c	250	if (!qu->answer->rrs.untyped) return;
98a3f706	251
98a3f706	252	cbyte= anstart;
98a3f706	253	arstart= -1;
98a3f706	254	for (rri=0; rri<ancount; rri++) {
3955725c	255	st= adns__findrr(qu,serv, dgram,dglen,&cbyte,
	256	&rrtype,&rrclass,&rdlength,&rdstart,
	257	&ownermatched);
98a3f706	258	assert(!st); assert(rrtype != -1);
98a3f706	259	if (rrclass != DNS_CLASS_IN \|\|
31144a72	260	rrtype != (qu->typei->type & adns__rrt_typemask) \|\|
31144a72	261	!ownermatched)
98a3f706	262	continue;
3955725c	263	assert(qu->answer->nrrs<wantedrrs);
	264	st= qu->typei->parse(qu,serv,
	265	dgram,dglen, rdstart,rdstart+rdlength,
	266	qu->answer->rrs.bytes+qu->answer->nrrs*qu->typei->rrsz);
	267	if (st) { adns__query_fail(qu,st); return; }
31144a72	268	if (rdstart==-1) goto x_truncated;
86e7b8d9	269	qu->answer->nrrs++;
98a3f706	270	}
b9de380c	271
98a3f706	272	/* This may have generated some child queries ... */
	273	if (qu->children.head) {
	274	qu->state= query_child;
	275	LIST_LINK_TAIL(ads->childw,qu);
	276	return;
b9de380c	277	}
ec477b9e	278
3955725c	279	adns__query_done(qu);
98a3f706	280	return;
0ba0614a	281
e576be50	282	x_truncated:
98a3f706	283	if (!flg_tc) {
31144a72	284	adns__diag(ads,serv,qu,"server sent datagram which points outside itself");
3955725c	285	adns__query_fail(qu,adns_s_serverfaulty);
98a3f706	286	return;
98a3f706	287	}
3955725c	288	if (qu->cname_dgram) { cname_recurse(qu,adns_qf_usevc); return; }
3955725c	289	adns__reset_cnameonly(qu);
98a3f706	290	qu->flags \|= adns_qf_usevc;
3955725c	291	adns__query_udp(qu,now);
98a3f706	292	}