diff options
Diffstat (limited to 'src/lib/dhcp/pkt.cc')
| -rw-r--r-- | src/lib/dhcp/pkt.cc | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/src/lib/dhcp/pkt.cc b/src/lib/dhcp/pkt.cc new file mode 100644 index 0000000..4d214c7 --- /dev/null +++ b/src/lib/dhcp/pkt.cc @@ -0,0 +1,269 @@ +// Copyright (C) 2014-2022 Internet Systems Consortium, Inc. ("ISC") +// +// This Source Code Form is subject to the terms of the Mozilla Public +// License, v. 2.0. If a copy of the MPL was not distributed with this +// file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#include <config.h> +#include <utility> +#include <dhcp/pkt.h> +#include <dhcp/iface_mgr.h> +#include <dhcp/hwaddr.h> +#include <vector> + +namespace isc { +namespace dhcp { + +Pkt::Pkt(uint32_t transid, const isc::asiolink::IOAddress& local_addr, + const isc::asiolink::IOAddress& remote_addr, uint16_t local_port, + uint16_t remote_port) + : transid_(transid), iface_(""), ifindex_(-1), local_addr_(local_addr), + remote_addr_(remote_addr), local_port_(local_port), + remote_port_(remote_port), buffer_out_(0), copy_retrieved_options_(false) { +} + +Pkt::Pkt(const uint8_t* buf, uint32_t len, const isc::asiolink::IOAddress& local_addr, + const isc::asiolink::IOAddress& remote_addr, uint16_t local_port, + uint16_t remote_port) + : transid_(0), iface_(""), ifindex_(-1), local_addr_(local_addr), + remote_addr_(remote_addr), local_port_(local_port), + remote_port_(remote_port), buffer_out_(0), copy_retrieved_options_(false) { + if (len != 0) { + if (buf == NULL) { + isc_throw(InvalidParameter, "data buffer passed to Pkt is NULL"); + } + data_.resize(len); + memcpy(&data_[0], buf, len); + } +} + +void +Pkt::addOption(const OptionPtr& opt) { + options_.insert(std::pair<int, OptionPtr>(opt->getType(), opt)); +} + +OptionPtr +Pkt::getNonCopiedOption(const uint16_t type) const { + const auto& x = options_.find(type); + if (x != options_.end()) { + return (x->second); + } + return (OptionPtr()); +} + +OptionPtr +Pkt::getOption(const uint16_t type) { + const auto& x = options_.find(type); + if (x != options_.end()) { + if (copy_retrieved_options_) { + OptionPtr option_copy = x->second->clone(); + x->second = option_copy; + } + return (x->second); + } + return (OptionPtr()); // NULL +} + +bool +Pkt::delOption(uint16_t type) { + const auto& x = options_.find(type); + if (x != options_.end()) { + options_.erase(x); + return (true); // delete successful + } else { + return (false); // can't find option to be deleted + } +} + +bool +Pkt::inClass(const std::string& client_class) { + return (classes_.contains(client_class)); +} + +void +Pkt::addClass(const std::string& client_class, bool required) { + // Always have ALL first. + if (classes_.empty()) { + classes_.insert("ALL"); + } + ClientClasses& classes = !required ? classes_ : required_classes_; + if (!classes.contains(client_class)) { + classes.insert(client_class); + } +} + +void +Pkt::updateTimestamp() { + timestamp_ = boost::posix_time::microsec_clock::universal_time(); +} + +void Pkt::repack() { + if (!data_.empty()) { + buffer_out_.writeData(&data_[0], data_.size()); + } +} + +void +Pkt::setRemoteHWAddr(const uint8_t htype, const uint8_t hlen, + const std::vector<uint8_t>& hw_addr) { + setHWAddrMember(htype, hlen, hw_addr, remote_hwaddr_); +} + +void +Pkt::setRemoteHWAddr(const HWAddrPtr& hw_addr) { + if (!hw_addr) { + isc_throw(BadValue, "Setting remote HW address to NULL is" + << " forbidden."); + } + remote_hwaddr_ = hw_addr; +} + +void +Pkt::setHWAddrMember(const uint8_t htype, const uint8_t, + const std::vector<uint8_t>& hw_addr, + HWAddrPtr& storage) { + storage.reset(new HWAddr(hw_addr, htype)); +} + +HWAddrPtr +Pkt::getMAC(uint32_t hw_addr_src) { + HWAddrPtr mac; + + /// @todo: Implement an array of method pointers instead of set of ifs + + // Method 1: from raw sockets. + if (hw_addr_src & HWAddr::HWADDR_SOURCE_RAW) { + mac = getRemoteHWAddr(); + if (mac) { + mac->source_ = HWAddr::HWADDR_SOURCE_RAW; + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_RAW) { + // If we're interested only in RAW sockets as source of that info, + // there's no point in trying other options. + return (HWAddrPtr()); + } + } + + // Method 2: From client link-layer address option inserted by a relay + if (hw_addr_src & HWAddr::HWADDR_SOURCE_CLIENT_ADDR_RELAY_OPTION) { + mac = getMACFromIPv6RelayOpt(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_CLIENT_ADDR_RELAY_OPTION) { + // If we're interested only in RFC6939 link layer address as source + // of that info, there's no point in trying other options. + return (HWAddrPtr()); + } + } + + // Method 3: Extracted from DUID-LLT or DUID-LL + if(hw_addr_src & HWAddr::HWADDR_SOURCE_DUID) { + mac = getMACFromDUID(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DUID) { + // If the only source allowed is DUID then we can skip the other + // methods. + return (HWAddrPtr()); + } + } + + // Method 4: Extracted from source IPv6 link-local address + if (hw_addr_src & HWAddr::HWADDR_SOURCE_IPV6_LINK_LOCAL) { + mac = getMACFromSrcLinkLocalAddr(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_IPV6_LINK_LOCAL) { + // If we're interested only in link-local addr as source of that + // info, there's no point in trying other options. + return (HWAddrPtr()); + } + } + + // Method 5: From remote-id option inserted by a relay + if(hw_addr_src & HWAddr::HWADDR_SOURCE_REMOTE_ID) { + mac = getMACFromRemoteIdRelayOption(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_REMOTE_ID) { + // If the only source allowed is remote-id option then we can skip + // the other methods. + return (HWAddrPtr()); + } + } + + // Method 6: From subscriber-id option inserted by a relay + + // Method 7: From docsis options + if (hw_addr_src & HWAddr::HWADDR_SOURCE_DOCSIS_CMTS) { + mac = getMACFromDocsisCMTS(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DOCSIS_CMTS) { + // If we're interested only in CMTS options as a source of that + // info, there's no point in trying other options. + return (HWAddrPtr()); + } + } + + // Method 8: From docsis options + if (hw_addr_src & HWAddr::HWADDR_SOURCE_DOCSIS_MODEM) { + mac = getMACFromDocsisModem(); + if (mac) { + return (mac); + } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DOCSIS_MODEM) { + // If we're interested only in CMTS options as a source of that + // info, there's no point in trying other options. + return (HWAddrPtr()); + } + } + + // Ok, none of the methods were suitable. Return NULL. + return (HWAddrPtr()); +} + +HWAddrPtr +Pkt::getMACFromIPv6(const isc::asiolink::IOAddress& addr) { + HWAddrPtr mac; + + if (addr.isV6LinkLocal()) { + std::vector<uint8_t> bin = addr.toBytes(); + + // Double check that it's of appropriate size + if ((bin.size() == isc::asiolink::V6ADDRESS_LEN) && + // Check that it's link-local (starts with fe80). + (bin[0] == 0xfe) && (bin[1] == 0x80) && + // Check that u bit is set and g is clear. + // See Section 2.5.1 of RFC2373 for details. + ((bin[8] & 3) == 2) && + // And that the IID is of EUI-64 type. + (bin[11] == 0xff) && (bin[12] == 0xfe)) { + + // Remove 8 most significant bytes + bin.erase(bin.begin(), bin.begin() + 8); + + // Ok, we're down to EUI-64 only now: XX:XX:XX:ff:fe:XX:XX:XX + bin.erase(bin.begin() + 3, bin.begin() + 5); + + // MAC-48 to EUI-64 involves inverting u bit (see explanation + // in Section 2.5.1 of RFC2373). We need to revert that. + bin[0] = bin[0] ^ 2; + + // Let's get the interface this packet was received on. + // We need it to get hardware type + IfacePtr iface = IfaceMgr::instance().getIface(iface_); + uint16_t hwtype = 0; // not specified + if (iface) { + hwtype = iface->getHWType(); + } + + mac.reset(new HWAddr(bin, hwtype)); + mac->source_ = HWAddr::HWADDR_SOURCE_IPV6_LINK_LOCAL; + } + } + + return (mac); +} + +} // end of namespace isc::dhcp +} // end of namespace isc |