From 3cd01b932e1c85394272ae64fae67ebeda92fb00 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 13 Apr 2024 23:11:59 +0200 Subject: Adding upstream version 1.8.3. Signed-off-by: Daniel Baumann --- xpf.cc | 118 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 118 insertions(+) create mode 100644 xpf.cc (limited to 'xpf.cc') diff --git a/xpf.cc b/xpf.cc new file mode 100644 index 0000000..2db6aaf --- /dev/null +++ b/xpf.cc @@ -0,0 +1,118 @@ +/* + * 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 "xpf.hh" + +std::string generateXPFPayload(bool tcp, const ComboAddress& source, const ComboAddress& destination) +{ + if (source.sin4.sin_family != destination.sin4.sin_family) { + throw std::runtime_error("The XPF destination and source addresses must be of the same family"); + } + + std::string ret; + const uint8_t version = source.isIPv4() ? 4 : 6; + const uint8_t protocol = tcp ? 6 : 17; + const size_t addrSize = source.isIPv4() ? sizeof(source.sin4.sin_addr.s_addr) : sizeof(source.sin6.sin6_addr.s6_addr); + const uint16_t sourcePort = source.sin4.sin_port; + const uint16_t destinationPort = destination.sin4.sin_port; + + ret.reserve(sizeof(version) + sizeof(protocol) + (addrSize * 2) + sizeof(sourcePort) + sizeof(destinationPort)); + + ret.append(reinterpret_cast(&version), sizeof(version)); + ret.append(reinterpret_cast(&protocol), sizeof(protocol)); + + // We already established source and destination sin_family equivalence + if (source.isIPv4()) { + assert(addrSize == sizeof(source.sin4.sin_addr.s_addr)); + ret.append(reinterpret_cast(&source.sin4.sin_addr.s_addr), addrSize); + assert(addrSize == sizeof(destination.sin4.sin_addr.s_addr)); + ret.append(reinterpret_cast(&destination.sin4.sin_addr.s_addr), addrSize); + } + else { + assert(addrSize == sizeof(source.sin6.sin6_addr.s6_addr)); + ret.append(reinterpret_cast(&source.sin6.sin6_addr.s6_addr), addrSize); + assert(addrSize == sizeof(destination.sin6.sin6_addr.s6_addr)); + ret.append(reinterpret_cast(&destination.sin6.sin6_addr.s6_addr), addrSize); + } + + ret.append(reinterpret_cast(&sourcePort), sizeof(sourcePort)); + ret.append(reinterpret_cast(&destinationPort), sizeof(destinationPort)); + + return ret; +} + +bool parseXPFPayload(const char* payload, size_t len, ComboAddress& source, ComboAddress* destination) +{ + static const size_t addr4Size = sizeof(source.sin4.sin_addr.s_addr); + static const size_t addr6Size = sizeof(source.sin6.sin6_addr.s6_addr); + uint8_t version; + uint8_t protocol; + uint16_t sourcePort; + uint16_t destinationPort; + + if (len != (sizeof(version) + sizeof(protocol) + (addr4Size * 2) + sizeof(sourcePort) + sizeof(destinationPort)) && + len != (sizeof(version) + sizeof(protocol) + (addr6Size * 2) + sizeof(sourcePort) + sizeof(destinationPort))) { + return false; + } + + size_t pos = 0; + + memcpy(&version, payload + pos, sizeof(version)); + pos += sizeof(version); + + if (version != 4 && version != 6) { + return false; + } + + memcpy(&protocol, payload + pos, sizeof(protocol)); + pos += sizeof(protocol); + + if (protocol != 6 && protocol != 17) { + return false; + } + + const size_t addrSize = version == 4 ? sizeof(source.sin4.sin_addr.s_addr) : sizeof(source.sin6.sin6_addr.s6_addr); + if (len - pos != ((addrSize * 2) + sizeof(sourcePort) + sizeof(destinationPort))) { + return false; + } + + source = makeComboAddressFromRaw(version, payload + pos, addrSize); + pos += addrSize; + if (destination != nullptr) { + *destination = makeComboAddressFromRaw(version, payload + pos, addrSize); + } + pos += addrSize; + + memcpy(&sourcePort, payload + pos, sizeof(sourcePort)); + pos += sizeof(sourcePort); + source.sin4.sin_port = sourcePort; + + memcpy(&destinationPort, payload + pos, sizeof(destinationPort)); + pos += sizeof(destinationPort); + (void) pos; + + if (destination != nullptr) { + destination->sin4.sin_port = destinationPort; + } + + return true; +} -- cgit v1.2.3