diff options
-rw-r--r-- | lib/kernel/src/inet_dns.erl | 34 |
1 files changed, 22 insertions, 12 deletions
diff --git a/lib/kernel/src/inet_dns.erl b/lib/kernel/src/inet_dns.erl index 669a361c9d..20a9c8055f 100644 --- a/lib/kernel/src/inet_dns.erl +++ b/lib/kernel/src/inet_dns.erl @@ -129,27 +129,33 @@ do_decode(<<Id:16, RA:1,PR:1,_:2,Rcode:4, QdCount:16,AnCount:16,NsCount:16,ArCount:16, QdBuf/binary>>=Buffer) -> - {AnBuf,QdList} = decode_query_section(QdBuf,QdCount,Buffer), - {NsBuf,AnList} = decode_rr_section(AnBuf,AnCount,Buffer), - {ArBuf,NsList} = decode_rr_section(NsBuf,NsCount,Buffer), - {Rest,ArList} = decode_rr_section(ArBuf,ArCount,Buffer), + {AnBuf,QdList,QdTC} = decode_query_section(QdBuf,QdCount,Buffer), + {NsBuf,AnList,AnTC} = decode_rr_section(AnBuf,AnCount,Buffer), + {ArBuf,NsList,NsTC} = decode_rr_section(NsBuf,NsCount,Buffer), + {Rest,ArList,ArTC} = decode_rr_section(ArBuf,ArCount,Buffer), case Rest of <<>> -> + HdrTC = decode_boolean(TC), DnsHdr = #dns_header{id=Id, qr=decode_boolean(QR), opcode=decode_opcode(Opcode), aa=decode_boolean(AA), - tc=decode_boolean(TC), + tc=HdrTC, rd=decode_boolean(RD), ra=decode_boolean(RA), pr=decode_boolean(PR), rcode=Rcode}, - #dns_rec{header=DnsHdr, - qdlist=QdList, - anlist=AnList, - nslist=NsList, - arlist=ArList}; + case QdTC or AnTC or NsTC or ArTC of + true when not HdrTC -> + throw(?DECODE_ERROR); + _ -> + #dns_rec{header=DnsHdr, + qdlist=QdList, + anlist=AnList, + nslist=NsList, + arlist=ArList} + end; _ -> %% Garbage data after DNS message throw(?DECODE_ERROR) @@ -161,8 +167,10 @@ do_decode(_) -> decode_query_section(Bin, N, Buffer) -> decode_query_section(Bin, N, Buffer, []). +decode_query_section(<<>>=Rest, N, _Buffer, Qs) -> + {Rest,reverse(Qs),N =/= 0}; decode_query_section(Rest, 0, _Buffer, Qs) -> - {Rest,reverse(Qs)}; + {Rest,reverse(Qs),false}; decode_query_section(Bin, N, Buffer, Qs) -> case decode_name(Bin, Buffer) of {<<Type:16,Class:16,Rest/binary>>,Name} -> @@ -179,8 +187,10 @@ decode_query_section(Bin, N, Buffer, Qs) -> decode_rr_section(Bin, N, Buffer) -> decode_rr_section(Bin, N, Buffer, []). +decode_rr_section(<<>>=Rest, N, _Buffer, RRs) -> + {Rest,reverse(RRs),N =/= 0}; decode_rr_section(Rest, 0, _Buffer, RRs) -> - {Rest,reverse(RRs)}; + {Rest,reverse(RRs),false}; decode_rr_section(Bin, N, Buffer, RRs) -> case decode_name(Bin, Buffer) of {<<T:16/unsigned,C:16/unsigned,TTL:4/binary, |