From 4fc2f55f761d71aae1f145d5aa94ba929cc39676 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 11:34:30 +0200 Subject: Adding upstream version 1.7.3. Signed-off-by: Daniel Baumann --- protozero.cc | 159 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 159 insertions(+) create mode 100644 protozero.cc (limited to 'protozero.cc') diff --git a/protozero.cc b/protozero.cc new file mode 100644 index 0000000..7d13a9c --- /dev/null +++ b/protozero.cc @@ -0,0 +1,159 @@ +/* + * This file is part of PowerDNS or dnsdist. + * Copyright -- PowerDNS.COM B.V. and its contributors + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of version 2 of the GNU General Public License as + * published by the Free Software Foundation. + * + * In addition, for the avoidance of any doubt, permission is granted to + * link this program with OpenSSL and to (re)distribute the binaries + * produced as the result of such linking. + * + * 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. + */ + +#include "protozero.hh" +#include "dnsparser.hh" + +void pdns::ProtoZero::Message::encodeComboAddress(const protozero::pbf_tag_type type, const ComboAddress& ca) +{ + if (ca.sin4.sin_family == AF_INET) { + d_message.add_bytes(type, reinterpret_cast(&ca.sin4.sin_addr.s_addr), sizeof(ca.sin4.sin_addr.s_addr)); + } + else if (ca.sin4.sin_family == AF_INET6) { + d_message.add_bytes(type, reinterpret_cast(&ca.sin6.sin6_addr.s6_addr), sizeof(ca.sin6.sin6_addr.s6_addr)); + } +} + +void pdns::ProtoZero::Message::encodeNetmask(const protozero::pbf_tag_type type, const Netmask& subnet, uint8_t mask) +{ + if (!subnet.empty()) { + ComboAddress ca(subnet.getNetwork()); + ca.truncate(mask); + if (ca.sin4.sin_family == AF_INET) { + d_message.add_bytes(type, reinterpret_cast(&ca.sin4.sin_addr.s_addr), sizeof(ca.sin4.sin_addr.s_addr)); + } + else if (ca.sin4.sin_family == AF_INET6) { + d_message.add_bytes(type, reinterpret_cast(&ca.sin6.sin6_addr.s6_addr), sizeof(ca.sin6.sin6_addr.s6_addr)); + } + } +} + +void pdns::ProtoZero::Message::encodeDNSName(protozero::pbf_writer& pbf, std::string& buffer, const protozero::pbf_tag_type type, const DNSName& name) +{ + // this will append the tag, mark the current position then reserve enough place to write the size + protozero::pbf_writer pbf_name{pbf, type}; + // we append the name to the buffer + name.toString(buffer); + // leaving the block will cause the sub writer to compute how much was written based on the new size and update the size accordingly +} + +void pdns::ProtoZero::Message::setRequest(const boost::uuids::uuid& uniqueId, const ComboAddress& requestor, const ComboAddress& local, const DNSName& qname, uint16_t qtype, uint16_t qclass, uint16_t id, pdns::ProtoZero::Message::TransportProtocol proto, size_t len) +{ + setMessageIdentity(uniqueId); + setSocketFamily(requestor.sin4.sin_family); + setSocketProtocol(proto); + setFrom(requestor); + setTo(local); + setInBytes(len); + setTime(); + setId(id); + setQuestion(qname, qtype, qclass); + setFromPort(requestor.getPort()); + setToPort(local.getPort()); +} + +void pdns::ProtoZero::Message::setResponse(const DNSName& qname, uint16_t qtype, uint16_t qclass) +{ + setType(pdns::ProtoZero::Message::MessageType::DNSResponseType); + setQuestion(qname, qtype, qclass); +} + +void pdns::ProtoZero::Message::addRRsFromPacket(const char* packet, const size_t len, bool includeCNAME) +{ + if (len < sizeof(struct dnsheader)) { + return; + } + + const struct dnsheader* dh = reinterpret_cast(packet); + + if (ntohs(dh->ancount) == 0) { + return; + } + + if (ntohs(dh->qdcount) == 0) { + return; + } + + PacketReader pr(pdns_string_view(packet, len)); + + size_t idx = 0; + DNSName rrname; + uint16_t qdcount = ntohs(dh->qdcount); + uint16_t ancount = ntohs(dh->ancount); + uint16_t rrtype; + uint16_t rrclass; + string blob; + struct dnsrecordheader ah; + + rrname = pr.getName(); + rrtype = pr.get16BitInt(); + rrclass = pr.get16BitInt(); + (void) rrtype; + (void) rrclass; + + /* consume remaining qd if any */ + if (qdcount > 1) { + for(idx = 1; idx < qdcount; idx++) { + rrname = pr.getName(); + rrtype = pr.get16BitInt(); + rrclass = pr.get16BitInt(); + (void) rrtype; + (void) rrclass; + } + } + + /* parse AN */ + for (idx = 0; idx < ancount; idx++) { + rrname = pr.getName(); + pr.getDnsrecordheader(ah); + + if (ah.d_type == QType::A || ah.d_type == QType::AAAA) { + pr.xfrBlob(blob); + + addRR(rrname, ah.d_type, ah.d_class, ah.d_ttl, blob); + + } else if (ah.d_type == QType::CNAME && includeCNAME) { + protozero::pbf_writer pbf_rr{d_response, static_cast(pdns::ProtoZero::Message::ResponseField::rrs)}; + + encodeDNSName(pbf_rr, d_buffer, static_cast(pdns::ProtoZero::Message::RRField::name), rrname); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::type), ah.d_type); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::class_), ah.d_class); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::ttl), ah.d_ttl); + DNSName target; + pr.xfrName(target, true); + encodeDNSName(pbf_rr, d_buffer, static_cast(pdns::ProtoZero::Message::RRField::rdata), target); + } + else { + pr.xfrBlob(blob); + } + } +} + +void pdns::ProtoZero::Message::addRR(const DNSName& name, uint16_t uType, uint16_t uClass, uint32_t uTTL, const std::string& blob) +{ + protozero::pbf_writer pbf_rr{d_response, static_cast(pdns::ProtoZero::Message::ResponseField::rrs)}; + encodeDNSName(pbf_rr, d_buffer, static_cast(pdns::ProtoZero::Message::RRField::name), name); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::type), uType); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::class_), uClass); + pbf_rr.add_uint32(static_cast(pdns::ProtoZero::Message::RRField::ttl), uTTL); + pbf_rr.add_string(static_cast(pdns::ProtoZero::Message::RRField::rdata), blob); +} -- cgit v1.2.3