src/libsystemd-network/dhcp6-network.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2 /***
   3   Copyright © 2014 Intel Corporation. All rights reserved.
   4 ***/
   5
   6 #include <netinet/in.h>
   7 #include <stdio.h>
   8 #include <string.h>
   9
  10 #include "dhcp6-internal.h"
  11 #include "dhcp6-protocol.h"
  12 #include "fd-util.h"
  13 #include "socket-util.h"
  14
  15 int dhcp6_network_bind_udp_socket(int ifindex, const struct in6_addr *local_address) {
  16         union sockaddr_union src = {
  17                 .in6.sin6_family = AF_INET6,
  18                 .in6.sin6_addr = *ASSERT_PTR(local_address),
  19                 .in6.sin6_port = htobe16(DHCP6_PORT_CLIENT),
  20                 .in6.sin6_scope_id = ifindex,
  21         };
  22         _cleanup_close_ int s = -EBADF;
  23         int r;
  24
  25         assert(ifindex > 0);
  26
  27         s = socket(AF_INET6, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, IPPROTO_UDP);
  28         if (s < 0)
  29                 return -errno;
  30
  31         r = setsockopt_int(s, IPPROTO_IPV6, IPV6_V6ONLY, true);
  32         if (r < 0)
  33                 return r;
  34
  35         r = setsockopt_int(s, IPPROTO_IPV6, IPV6_MULTICAST_LOOP, false);
  36         if (r < 0)
  37                 return r;
  38
  39         r = setsockopt_int(s, SOL_SOCKET, SO_REUSEADDR, true);
  40         if (r < 0)
  41                 return r;
  42
  43         r = setsockopt_int(s, SOL_SOCKET, SO_TIMESTAMP, true);
  44         if (r < 0)
  45                 return r;
  46
  47         r = bind(s, &src.sa, sizeof(src.in6));
  48         if (r < 0)
  49                 return -errno;
  50
  51         return TAKE_FD(s);
  52 }
  53
  54 int dhcp6_network_send_udp_socket(int s, const struct in6_addr *server_address, const void *packet, size_t len) {
  55         union sockaddr_union dest = {
  56                 .in6.sin6_family = AF_INET6,
  57                 .in6.sin6_addr = *ASSERT_PTR(server_address),
  58                 .in6.sin6_port = htobe16(DHCP6_PORT_SERVER),
  59         };
  60
  61         if (sendto(s, packet, len, 0, &dest.sa, sizeof(dest.in6)) < 0)
  62                 return -errno;
  63
  64         return 0;
  65 }