| /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */ |
| /* |
| * Copyright (c) 2014-2022, Regents of the University of California, |
| * Arizona Board of Regents, |
| * Colorado State University, |
| * University Pierre & Marie Curie, Sorbonne University, |
| * Washington University in St. Louis, |
| * Beijing Institute of Technology, |
| * The University of Memphis. |
| * |
| * This file is part of NFD (Named Data Networking Forwarding Daemon). |
| * See AUTHORS.md for complete list of NFD authors and contributors. |
| * |
| * NFD is free software: you can redistribute it and/or modify it under the terms |
| * of the GNU General Public License as published by the Free Software Foundation, |
| * either version 3 of the License, or (at your option) any later version. |
| * |
| * NFD 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 |
| * NFD, e.g., in COPYING.md file. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include "udp-protocol.hpp" |
| |
| namespace nfd::udp { |
| |
| ssize_t |
| computeMtu(const Endpoint& localEndpoint) |
| { |
| size_t mtu = 0; |
| if (localEndpoint.address().is_v4()) { // IPv4 |
| mtu = std::numeric_limits<uint16_t>::max(); // maximum Total Length |
| mtu -= sizeof(uint32_t) * ((1 << 4) - 1); // maximum Internet Header Length |
| } |
| else { // IPv6 |
| mtu = std::numeric_limits<uint16_t>::max(); // maximum Payload Length |
| } |
| mtu -= sizeof(uint16_t) * 4; // size of UDP header |
| return mtu; |
| } |
| |
| } // namespace nfd::udp |