networkd: add a basic network daemon

This daemon listens for and configures network devices tagged with
'systemd-networkd'. By default, no devices are tagged so this daemon
can safely run in parallel with existing network daemons/scripts.

Networks are configured in /etc/systemd/network/*.network. The first .network
file that matches a given link is applied. The matching logic is similar to
the one for .link files, but additionally supports matching on interface name.

The mid-term aim is to provide an alternative to ad-hoc scripts currently used
in initrd's and for wired setups that don't change much (e.g., as seen on
servers/and some embedded systems).

Currently, static addresses and a gateway can be configured.

Example .network file:

[Match]
Name=wlp2s0

[Network]
Description=My Network
Gateway=192.168.1.1
Address=192.168.1.23/24
Address=fe80::9aee:94ff:fe3f:c618/64

1 files changed, 119 insertions, 0 deletions

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
new file mode 100644
index 0000000000..486d4de2c7
--- /dev/null
+++ b/src/network/networkd-link.c
@@ -0,0 +1,119 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 Tom Gundersen <teg@jklm.no>
+
+  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/ether.h>
+#include <linux/if.h>
+
+#include "networkd.h"
+#include "libudev-private.h"
+#include "util.h"
+
+int link_new(Manager *manager, struct udev_device *device, Link **ret) {
+        _cleanup_link_free_ Link *link = NULL;
+        uint64_t ifindex;
+        int r;
+
+        assert(device);
+        assert(ret);
+
+        link = new0(Link, 1);
+        if (!link)
+                return -ENOMEM;
+
+        ifindex = udev_device_get_ifindex(device);
+        if (ifindex <= 0)
+                return -EINVAL;
+
+        link->ifindex = ifindex;
+        link->manager = manager;
+
+        r = hashmap_put(manager->links, &ifindex, link);
+        if (r < 0)
+                return r;
+
+        *ret = link;
+        link = NULL;
+
+        return 0;
+}
+
+void link_free(Link *link) {
+        if (!link)
+                return;
+
+        network_free(link->network);
+
+        hashmap_remove(link->manager->links, link);
+
+        free(link);
+}
+
+int link_add(Manager *m, struct udev_device *device) {
+        Link *link;
+        Network *network;
+        int r;
+        uint64_t ifindex;
+
+        assert(m);
+        assert(device);
+
+        ifindex = udev_device_get_ifindex(device);
+        link = hashmap_get(m->links, &ifindex);
+        if (link)
+                return 0;
+
+        r = link_new(m, device, &link);
+        if (r < 0) {
+                log_error("could not create link: %s", strerror(-r));
+                return r;
+        }
+
+        r = network_get(m, device, &network);
+        if (r < 0)
+                return r == -ENOENT ? 0 : r;
+
+        r = network_apply(m, network, link);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+int link_up(Manager *manager, Link *link) {
+        _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
+        int r;
+
+        r = sd_rtnl_message_link_new(RTM_NEWLINK, link->ifindex, 0, IFF_UP, &req);
+        if (r < 0) {
+                log_error("Could not allocate RTM_NEWLINK message");
+                return r;
+        }
+
+        r = sd_rtnl_send_with_reply_and_block(manager->rtnl, req, 0, NULL);
+        if (r < 0) {
+                log_error("Could not UP link: %s", strerror(-r));
+                return r;
+        }
+
+        log_info("Link is UP");
+
+        return 0;
+}