garnet/bin/mdns/service/mdns_interface_transceiver_v6.cc

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "garnet/bin/mdns/service/mdns_interface_transceiver_v6.h"

#include <arpa/inet.h>
#include <errno.h>
#include <sys/socket.h>

#include "garnet/bin/mdns/service/mdns_addresses.h"
#include "src/lib/fxl/logging.h"

namespace mdns {

MdnsInterfaceTransceiverV6::MdnsInterfaceTransceiverV6(inet::IpAddress address,
                                                       const std::string& name,
                                                       uint32_t index)
    : MdnsInterfaceTransceiver(address, name, index) {}

MdnsInterfaceTransceiverV6::~MdnsInterfaceTransceiverV6() {}

int MdnsInterfaceTransceiverV6::SetOptionDisableMulticastLoop() {
  char param = 0;
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_MULTICAST_LOOP,
                          &param, sizeof(param));
  if (result < 0) {
    if (errno == ENOPROTOOPT) {
      FXL_LOG(WARNING) << "NET-291 IPV6_MULTICAST_LOOP not supported "
                          "(ENOPROTOOPT), continuing anyway";
      result = 0;
    } else {
      FXL_LOG(ERROR) << "Failed to set socket option IPV6_MULTICAST_LOOP, "
                     << strerror(errno);
    }
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SetOptionJoinMulticastGroup() {
  ipv6_mreq param;
  param.ipv6mr_multiaddr =
      MdnsAddresses::V6Multicast(mdns_port()).as_sockaddr_in6().sin6_addr;
  param.ipv6mr_interface = index();
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_JOIN_GROUP,
                          &param, sizeof(param));
  if (result < 0) {
    if (errno == ENODEV) {
      FXL_LOG(WARNING) << "NET-2180 IPV6_JOIN_GROUP returned ENODEV, mDNS will "
                          "not communicate via IPV6";
    } else {
      FXL_LOG(ERROR) << "Failed to set socket option IPV6_JOIN_GROUP, "
                     << strerror(errno);
    }
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SetOptionOutboundInterface() {
  uint32_t index = this->index();
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_MULTICAST_IF,
                          &index, sizeof(index));
  if (result < 0) {
    if (errno == EOPNOTSUPP) {
      FXL_LOG(WARNING) << "NET-1901 IPV6_MULTICAST_IF not supported "
                          "(EOPNOTSUPP), continuing anyway";
      result = 0;
    } else {
      FXL_LOG(ERROR) << "Failed to set socket option IPV6_MULTICAST_IF, "
                     << strerror(errno);
    }
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SetOptionUnicastTtl() {
  int param = kTimeToLive_;
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_UNICAST_HOPS,
                          &param, sizeof(param));
  if (result < 0) {
    FXL_LOG(ERROR) << "Failed to set socket option IPV6_UNICAST_HOPS, "
                   << strerror(errno);
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SetOptionMulticastTtl() {
  int param = kTimeToLive_;
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_MULTICAST_HOPS,
                          &param, sizeof(param));
  if (result < 0) {
    FXL_LOG(ERROR) << "Failed to set socket option IPV6_MULTICAST_HOPS, "
                   << strerror(errno);
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SetOptionFamilySpecific() {
  // Set hop limit.
  int param = 1;
  int result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_HOPLIMIT,
                          &param, sizeof(param));
  if (result < 0) {
    FXL_LOG(ERROR) << "Failed to set socket option IPV6_HOPLIMIT, "
                   << strerror(errno);
    return result;
  }

  // Receive V6 packets only.
  param = 1;
  result = setsockopt(socket_fd().get(), IPPROTO_IPV6, IPV6_V6ONLY, &param,
                      sizeof(param));
  if (result < 0) {
    FXL_LOG(ERROR) << "Failed to set socket option IPV6_V6ONLY, "
                   << strerror(errno);
    return false;
  }

  return result;
}

int MdnsInterfaceTransceiverV6::Bind() {
  int result =
      bind(socket_fd().get(), MdnsAddresses::V6Bind(mdns_port()).as_sockaddr(),
           MdnsAddresses::V6Bind(mdns_port()).socklen());
  if (result < 0) {
    FXL_LOG(ERROR) << "Failed to bind socket to V6 address, "
                   << strerror(errno);
  }

  return result;
}

int MdnsInterfaceTransceiverV6::SendTo(const void* buffer, size_t size,
                                       const inet::SocketAddress& address) {
  if (address == MdnsAddresses::V4Multicast(mdns_port())) {
    return sendto(socket_fd().get(), buffer, size, 0,
                  MdnsAddresses::V6Multicast(mdns_port()).as_sockaddr(),
                  MdnsAddresses::V6Multicast(mdns_port()).socklen());
  }

  return sendto(socket_fd().get(), buffer, size, 0, address.as_sockaddr(),
                address.socklen());
}

}  // namespace mdns