sd-network: IPv4 link-local support [v2]

Implements IPv4LL with respect to RFC 3927
(http://tools.ietf.org/rfc/rfc3927.txt) and integrates it
with networkd. Majority of the IPv4LL state machine is
taken from avahi (http://avahi.org/) project's autoip.

IPv4LL can be enabled by IPv4LL=yes under [Network]
section of .network file.

IPv4LL works independent of DHCP but if DHCP lease is
aquired, then LL address will be dropped.

[tomegun: removed a trailing newline and a compiler warning]

1 files changed, 38 insertions, 0 deletions

diff --git a/src/libsystemd-network/ipv4ll-internal.h b/src/libsystemd-network/ipv4ll-internal.h
new file mode 100644
index 0000000000..fe5ef8e2b8
--- /dev/null
+++ b/src/libsystemd-network/ipv4ll-internal.h
@@ -0,0 +1,38 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+  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 <netinet/if_ether.h>
+
+#include "sparse-endian.h"
+#include "socket-util.h"
+
+int arp_network_bind_raw_socket(int index, union sockaddr_union *link);
+int arp_network_send_raw_socket(int fd, const union sockaddr_union *link,
+                                        const struct ether_arp *arp);
+
+void arp_packet_init(struct ether_arp *arp);
+void arp_packet_probe(struct ether_arp *arp, be32_t pa, const struct ether_addr *ha);
+void arp_packet_announcement(struct ether_arp *arp, be32_t pa, const struct ether_addr *ha);
+int arp_packet_verify_headers(struct ether_arp *arp);
+
+#define log_ipv4ll(ll, fmt, ...) log_meta(LOG_DEBUG, __FILE__, __LINE__, __func__, "IPv4LL: " fmt, ##__VA_ARGS__)