X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=adns.git;a=blobdiff_plain;f=src%2Freply.c;h=ab7c8ff4aadbc37c6cdb589baf43b49aa384cc88;hp=673196e20c55f9b376dec593e840c4559618871d;hb=c3ca23bb1821f820dfa889dc006599b5df8af32f;hpb=ffbda80c54147d112c125f208f6611daf09358b3 diff --git a/src/reply.c b/src/reply.c index 673196e..ab7c8ff 100644 --- a/src/reply.c +++ b/src/reply.c @@ -3,7 +3,7 @@ * - main handling and parsing routine for received datagrams */ /* - * This file is part of adns, which is Copyright (C) 1997, 1998 Ian Jackson + * This file is part of adns, which is Copyright (C) 1997-1999 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 @@ -20,24 +20,27 @@ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -#include "internal.h" +#include +#include -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); -} +#include "internal.h" 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 rrtype, rrclass, rdlength, rdstart; int anstart, nsstart, arstart; + int ownermatched, l, nrrs; + unsigned long ttl, soattl; + const typeinfo *typei; adns_query qu, nqu; dns_rcode rcode; adns_status st; vbuf tempvb; + byte *newquery, *rrsdata; + parseinfo pai; if (dglen>3; - flg_tc= f1&0x20; + flg_tc= f1&0x02; flg_rd= f1&0x01; flg_ra= f2&0x80; rcode= (f2&0x0f); @@ -92,13 +95,13 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, 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)); + id, adns__diag_domain(ads,serv,0,&tempvb,dgram,dglen,DNS_HDRSIZE)); adns__vbuf_free(&tempvb); } return; } anstart= qu->query_dglen; + arstart= -1; LIST_UNLINK(ads->timew,qu); /* We're definitely going to do something with this query now */ @@ -109,22 +112,22 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, break; case rcode_formaterror: adns__warn(ads,serv,qu,"server cannot understand our query (Format Error)"); - adns__query_fail(qu,adns_s_serverfaulty); + adns__query_fail(qu,adns_s_rcodeformaterror); return; case rcode_servfail: - adns__query_fail(qu,adns_s_servfail); + adns__query_fail(qu,adns_s_rcodeservfail); return; case rcode_notimp: adns__warn(ads,serv,qu,"server claims not to implement our query"); - adns__query_fail(qu,adns_s_notimplemented); + adns__query_fail(qu,adns_s_rcodenotimplemented); return; case rcode_refused: adns__warn(ads,serv,qu,"server refused our query"); - adns__query_fail(qu,adns_s_refused); + adns__query_fail(qu,adns_s_rcoderefused); return; default: adns__warn(ads,serv,qu,"server gave unknown response code %d",rcode); - adns__query_fail(qu,adns_s_reasonunknown); + adns__query_fail(qu,adns_s_rcodeunknown); return; } @@ -136,7 +139,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, for (rri= 0; rriiflags & 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)); + adns__diag_domain(ads,serv,qu, &qu->vb, 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; + if (qu->flags & adns_qf_cname_forbid) { + adns__query_fail(qu,adns_s_prohibitedcname); + return; + } else if (!qu->cname_dgram) { /* Ignore second and subsequent CNAMEs */ qu->cname_begin= rdstart; qu->cname_dglen= dglen; - st= adns__parse_domain(ads,serv,qu, &qu->vb,qu->flags, + st= adns__parse_domain(ads,serv,qu, &qu->vb, + qu->flags & adns_qf_quoteok_cname ? pdf_quoteok : 0, 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; + if (!qu->answer->cname) { adns__query_fail(qu,adns_s_nomemory); return; } + + qu->cname_dgram= adns__alloc_mine(qu,dglen); + memcpy(qu->cname_dgram,dgram,dglen); + memcpy(qu->answer->cname,qu->vb.buf,l); cname_here= 1; + adns__update_expires(qu,ttl,now); /* 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 @@ -177,8 +186,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, */ } 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), + adns__diag_domain(ads,serv,qu, &qu->vb, dgram,dglen,rdstart), qu->answer->cname); } } else if (rrtype == (qu->typei->type & adns__rrt_typemask)) { @@ -188,23 +196,22 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, } } - /* If we got here then the answer section is intact. */ + /* We defer handling truncated responses here, in case there was a CNAME + * which we could use. + */ + if (flg_tc) goto x_truncated; + 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; + foundsoa= 0; soattl= 0; foundns= 0; for (rri= 0; rriflags & adns_qf_search) { + adns__search_next(ads,qu,now); + } else { + adns__query_fail(qu,adns_s_nxdomain); + } + return; + } if (foundsoa || !foundns) { /* Aha ! A NODATA response, good. */ + adns__update_expires(qu,soattl,now); adns__query_fail(qu,adns_s_nodata); return; } @@ -228,7 +248,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, * 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; } + if (cname_here) goto x_restartquery; /* Bloody hell, I thought we asked for recursion ? */ if (flg_rd) { @@ -239,7 +259,7 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, 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__query_fail(qu,adns_s_invalidresponse); } return; } @@ -247,27 +267,39 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, /* 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; + if (!qu->answer->rrs.untyped) { adns__query_fail(qu,adns_s_nomemory); return; } + typei= qu->typei; cbyte= anstart; - arstart= -1; - for (rri=0; rrianswer->rrs.bytes; + + pai.ads= qu->ads; + pai.qu= qu; + pai.serv= serv; + pai.dgram= dgram; + pai.dglen= dglen; + pai.nsstart= nsstart; + pai.nscount= nscount; + pai.arcount= arcount; + pai.now= now; + + for (rri=0, nrrs=0; rritypei->type & adns__rrt_typemask) || !ownermatched) continue; - assert(qu->answer->nrrstypei->parse(qu,serv, - dgram,dglen, rdstart,rdstart+rdlength, - qu->answer->rrs.bytes+qu->answer->nrrs*qu->typei->rrsz); + adns__update_expires(qu,ttl,now); + st= typei->parse(&pai, rdstart,rdstart+rdlength, rrsdata+nrrs*typei->rrsz); if (st) { adns__query_fail(qu,st); return; } if (rdstart==-1) goto x_truncated; - qu->answer->nrrs++; + nrrs++; } + assert(nrrs==wantedrrs); + qu->answer->nrrs= nrrs; /* This may have generated some child queries ... */ if (qu->children.head) { @@ -280,13 +312,30 @@ void adns__procdgram(adns_state ads, const byte *dgram, int dglen, 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); + adns__query_fail(qu,adns_s_invalidresponse); return; } - if (qu->cname_dgram) { cname_recurse(qu,adns_qf_usevc); return; } - adns__reset_cnameonly(qu); qu->flags |= adns_qf_usevc; + + x_restartquery: + + if (qu->cname_dgram) { + st= adns__mkquery_frdgram(qu->ads,&qu->vb,&qu->id, + qu->cname_dgram, qu->cname_dglen, qu->cname_begin, + qu->typei->type, qu->flags); + if (st) { adns__query_fail(qu,st); return; } + + newquery= realloc(qu->query_dgram,qu->vb.used); + if (!newquery) { adns__query_fail(qu,adns_s_nomemory); return; } + + qu->query_dgram= newquery; + qu->query_dglen= qu->vb.used; + memcpy(newquery,qu->vb.buf,qu->vb.used); + } + + adns__reset_cnameonly(qu); adns__query_udp(qu,now); }