/*** This file is part of systemd. Copyright (C) 2014 Axis Communications AB. All rights reserved. systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd 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 Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include <arpa/inet.h> #include "util.h" #include "ipv4ll-internal.h" void arp_packet_init(struct ether_arp *arp) { assert(arp); memzero(arp, sizeof(struct ether_arp)); /* Header */ arp->ea_hdr.ar_hrd = htons(ARPHRD_ETHER); /* HTYPE */ arp->ea_hdr.ar_pro = htons(ETHERTYPE_IP); /* PTYPE */ arp->ea_hdr.ar_hln = ETH_ALEN; /* HLEN */ arp->ea_hdr.ar_pln = sizeof arp->arp_spa; /* PLEN */ arp->ea_hdr.ar_op = htons(ARPOP_REQUEST); /* REQUEST */ } void arp_packet_probe(struct ether_arp *arp, be32_t pa, const struct ether_addr *ha) { assert(ha); arp_packet_init(arp); memcpy(arp->arp_sha, ha, ETH_ALEN); memcpy(arp->arp_tpa, &pa, sizeof(pa)); } void arp_packet_announcement(struct ether_arp *arp, be32_t pa, const struct ether_addr *ha) { assert(ha); arp_packet_init(arp); memcpy(arp->arp_sha, ha, ETH_ALEN); memcpy(arp->arp_tpa, &pa, sizeof(pa)); memcpy(arp->arp_spa, &pa, sizeof(pa)); } int arp_packet_verify_headers(struct ether_arp *arp) { assert(arp); if (arp->ea_hdr.ar_hrd != htons(ARPHRD_ETHER)) { log_ipv4ll(NULL, "ignoring packet: header is not ARPHRD_ETHER"); return -EINVAL; } if (arp->ea_hdr.ar_pro != htons(ETHERTYPE_IP)) { log_ipv4ll(NULL, "ignoring packet: protocol is not ETHERTYPE_IP"); return -EINVAL; } if (arp->ea_hdr.ar_op != htons(ARPOP_REQUEST) && arp->ea_hdr.ar_op != htons(ARPOP_REPLY)) { log_ipv4ll(NULL, "ignoring packet: operation is not ARPOP_REQUEST or ARPOP_REPLY"); return -EINVAL; } return 0; }