multicast-ethernet-transport.cpp
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1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
2 /*
3  * Copyright (c) 2014-2019, Regents of the University of California,
4  * Arizona Board of Regents,
5  * Colorado State University,
6  * University Pierre & Marie Curie, Sorbonne University,
7  * Washington University in St. Louis,
8  * Beijing Institute of Technology,
9  * The University of Memphis.
10  *
11  * This file is part of NFD (Named Data Networking Forwarding Daemon).
12  * See AUTHORS.md for complete list of NFD authors and contributors.
13  *
14  * NFD is free software: you can redistribute it and/or modify it under the terms
15  * of the GNU General Public License as published by the Free Software Foundation,
16  * either version 3 of the License, or (at your option) any later version.
17  *
18  * NFD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
19  * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
20  * PURPOSE. See the GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License along with
23  * NFD, e.g., in COPYING.md file. If not, see <http://www.gnu.org/licenses/>.
24  */
25 
27 #include "common/global.hpp"
28 
29 #include <cerrno> // for errno
30 #include <cstring> // for memcpy(), strerror(), strncpy()
31 #include <net/if.h> // for struct ifreq
32 #include <stdio.h> // for snprintf()
33 #include <sys/ioctl.h> // for ioctl()
34 
35 #if defined(__linux__)
36 #include <netpacket/packet.h> // for struct packet_mreq
37 #include <sys/socket.h> // for setsockopt()
38 #endif
39 
40 #ifdef SIOCADDMULTI
41 #if defined(__APPLE__) || defined(__FreeBSD__)
42 #include <net/if_dl.h> // for struct sockaddr_dl
43 #endif
44 #endif
45 
46 namespace nfd {
47 namespace face {
48 
49 NFD_LOG_INIT(MulticastEthernetTransport);
50 
51 MulticastEthernetTransport::MulticastEthernetTransport(const ndn::net::NetworkInterface& localEndpoint,
52  const ethernet::Address& mcastAddress,
53  ndn::nfd::LinkType linkType)
54  : EthernetTransport(localEndpoint, mcastAddress)
55 #if defined(__linux__)
56  , m_interfaceIndex(localEndpoint.getIndex())
57 #endif
58 {
59  this->setLocalUri(FaceUri::fromDev(m_interfaceName));
60  this->setRemoteUri(FaceUri(m_destAddress));
61  this->setScope(ndn::nfd::FACE_SCOPE_NON_LOCAL);
62  this->setPersistency(ndn::nfd::FACE_PERSISTENCY_PERMANENT);
63  this->setLinkType(linkType);
64  this->setMtu(localEndpoint.getMtu());
65 
66  NFD_LOG_FACE_DEBUG("Creating transport");
67 
68  char filter[110];
69  // note #1: we cannot use std::snprintf because it's not available
70  // on some platforms (see #2299)
71  // note #2: "not vlan" must appear last in the filter expression, or the
72  // rest of the filter won't work as intended (see pcap-filter(7))
73  snprintf(filter, sizeof(filter),
74  "(ether proto 0x%x) && (ether dst %s) && (not ether src %s) && (not vlan)",
75  ethernet::ETHERTYPE_NDN,
76  m_destAddress.toString().data(),
77  m_srcAddress.toString().data());
78  m_pcap.setPacketFilter(filter);
79 
80  BOOST_ASSERT(m_destAddress.isMulticast());
81  if (!m_destAddress.isBroadcast())
82  joinMulticastGroup();
83 }
84 
85 void
86 MulticastEthernetTransport::joinMulticastGroup()
87 {
88 #if defined(__linux__)
89  packet_mreq mr{};
90  mr.mr_ifindex = m_interfaceIndex;
91  mr.mr_type = PACKET_MR_MULTICAST;
92  mr.mr_alen = m_destAddress.size();
93  std::memcpy(mr.mr_address, m_destAddress.data(), m_destAddress.size());
94 
95  if (::setsockopt(m_socket.native_handle(), SOL_PACKET,
96  PACKET_ADD_MEMBERSHIP, &mr, sizeof(mr)) == 0)
97  return; // success
98 
99  NFD_LOG_FACE_WARN("setsockopt(PACKET_ADD_MEMBERSHIP) failed: " << std::strerror(errno));
100 #endif
101 
102 #if defined(SIOCADDMULTI)
103  ifreq ifr{};
104  std::strncpy(ifr.ifr_name, m_interfaceName.data(), sizeof(ifr.ifr_name) - 1);
105 
106 #if defined(__APPLE__) || defined(__FreeBSD__)
107  // see bug #2327
108  using boost::asio::ip::udp;
109  udp::socket sock(getGlobalIoService(), udp::v4());
110  int fd = sock.native_handle();
111 
112  // Differences between Linux and the BSDs (including macOS):
113  // o BSD does not have ifr_hwaddr; use ifr_addr instead.
114  // o While macOS seems to accept both AF_LINK and AF_UNSPEC as the address
115  // family, FreeBSD explicitly requires AF_LINK, so we have to use AF_LINK
116  // and sockaddr_dl instead of the generic sockaddr structure.
117  // o BSD's sockaddr (and sockaddr_dl in particular) contains an additional
118  // field, sa_len (sdl_len), which must be set to the total length of the
119  // structure, including the length field itself.
120  // o We do not specify the interface name, thus sdl_nlen is left at 0 and
121  // LLADDR is effectively the same as sdl_data.
122 
123  sockaddr_dl* sdl = reinterpret_cast<sockaddr_dl*>(&ifr.ifr_addr);
124  sdl->sdl_len = sizeof(ifr.ifr_addr);
125  sdl->sdl_family = AF_LINK;
126  sdl->sdl_alen = m_destAddress.size();
127  std::memcpy(LLADDR(sdl), m_destAddress.data(), m_destAddress.size());
128 
129  static_assert(sizeof(ifr.ifr_addr) >= offsetof(sockaddr_dl, sdl_data) + ethernet::ADDR_LEN,
130  "ifr_addr in struct ifreq is too small on this platform");
131 #else
132  int fd = m_socket.native_handle();
133 
134  ifr.ifr_hwaddr.sa_family = AF_UNSPEC;
135  std::memcpy(ifr.ifr_hwaddr.sa_data, m_destAddress.data(), m_destAddress.size());
136 
137  static_assert(sizeof(ifr.ifr_hwaddr.sa_data) >= ethernet::ADDR_LEN,
138  "ifr_hwaddr in struct ifreq is too small on this platform");
139 #endif
140 
141  if (::ioctl(fd, SIOCADDMULTI, &ifr) == 0)
142  return; // success
143 
144  NFD_LOG_FACE_WARN("ioctl(SIOCADDMULTI) failed: " << std::strerror(errno));
145 #endif
146 
147  NDN_THROW(Error("Failed to join multicast group"));
148 }
149 
150 } // namespace face
151 } // namespace nfd
void setLocalUri(const FaceUri &uri)
Definition: transport.hpp:394
void setScope(ndn::nfd::FaceScope scope)
Definition: transport.hpp:418
boost::asio::posix::stream_descriptor m_socket
void setMtu(ssize_t mtu)
Definition: transport.hpp:448
#define NFD_LOG_FACE_DEBUG(msg)
Log a message at DEBUG level.
#define NFD_LOG_FACE_WARN(msg)
Log a message at WARN level.
Base class for Ethernet-based Transports.
MulticastEthernetTransport(const ndn::net::NetworkInterface &localEndpoint, const ethernet::Address &mcastAddress, ndn::nfd::LinkType linkType)
Creates an Ethernet-based transport for multicast communication.
Copyright (c) 2014-2015, Regents of the University of California, Arizona Board of Regents...
Definition: algorithm.hpp:32
void setLinkType(ndn::nfd::LinkType linkType)
Definition: transport.hpp:436
void setPersistency(ndn::nfd::FacePersistency newPersistency)
changes face persistency setting
Definition: transport.cpp:150
#define NFD_LOG_INIT(name)
Definition: logger.hpp:31
void setRemoteUri(const FaceUri &uri)
Definition: transport.hpp:406
void setPacketFilter(const char *filter) const
Install a BPF filter on the receiving socket.
boost::asio::io_service & getGlobalIoService()
Returns the global io_service instance for the calling thread.
Definition: global.cpp:36