X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Flibsystemd-network%2Fipv4ll-packet.c;fp=src%2Flibsystemd-network%2Fipv4ll-packet.c;h=2b6c73ab4b7ea897089d6ac612cbfae364ecd080;hb=5c1d3fc93d91384bbac29adf01074fa4375317ea;hp=0000000000000000000000000000000000000000;hpb=b6b8adbff4b1a67a2fffc2c225f1b083d9e4a69e;p=elogind.git diff --git a/src/libsystemd-network/ipv4ll-packet.c b/src/libsystemd-network/ipv4ll-packet.c new file mode 100644 index 000000000..2b6c73ab4 --- /dev/null +++ b/src/libsystemd-network/ipv4ll-packet.c @@ -0,0 +1,71 @@ +/*** + 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 . +***/ +#include + +#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; +}