summaryrefslogtreecommitdiff
path: root/src/libsystemd-network/ipv4ll-packet.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/libsystemd-network/ipv4ll-packet.c')
-rw-r--r--src/libsystemd-network/ipv4ll-packet.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/src/libsystemd-network/ipv4ll-packet.c b/src/libsystemd-network/ipv4ll-packet.c
new file mode 100644
index 0000000000..2b6c73ab4b
--- /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 <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;
+}