src/libsystemd-network/ipv4ll-network.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright (C) 2014 Axis Communications AB. All rights reserved.
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include "util.h"
  21 #include "ipv4ll-internal.h"
  22
  23 int arp_network_send_raw_socket(int fd, const union sockaddr_union *link,
  24                                         const struct ether_arp *arp) {
  25         assert(arp);
  26         assert(link);
  27         assert(fd >= 0);
  28
  29         if (sendto(fd, arp, sizeof(struct ether_arp), 0, &link->sa, sizeof(link->ll)) < 0)
  30                 return -errno;
  31
  32         return 0;
  33 }
  34
  35 int arp_network_bind_raw_socket(int index, union sockaddr_union *link) {
  36         int s;
  37
  38         assert(index > 0);
  39         assert(link);
  40
  41         s = socket(PF_PACKET, SOCK_DGRAM | SOCK_CLOEXEC | SOCK_NONBLOCK, htons(ETH_P_ARP));
  42         if (s < 0)
  43                 return -errno;
  44
  45         link->ll.sll_family = AF_PACKET;
  46         link->ll.sll_ifindex = index;
  47         link->ll.sll_protocol = htons(ETH_P_ARP);
  48         link->ll.sll_halen = ETH_ALEN;
  49
  50         if (bind(s, &link->sa, sizeof(link->ll)) < 0) {
  51                 close_nointr_nofail(s);
  52                 return -errno;
  53         }
  54
  55         return s;
  56 }