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, 169 insertions, 0 deletions

diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
new file mode 100644
index 0000000000..9a7106e834
--- /dev/null
+++ b/src/network/networkd-address.c
@@ -0,0 +1,169 @@
+/*-*- 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 <net/if.h>
+
+#include "networkd.h"
+
+#include "utf8.h"
+#include "util.h"
+#include "conf-parser.h"
+#include "net-util.h"
+
+int address_new(Network *network, Address **ret) {
+        _cleanup_address_free_ Address *address = NULL;
+
+        address = new0(Address, 1);
+        if (!address)
+                return -ENOMEM;
+
+        address->network = network;
+
+        LIST_PREPEND(addresses, network->addresses, address);
+
+        *ret = address;
+        address = NULL;
+
+        return 0;
+}
+
+void address_free(Address *address) {
+        if (!address)
+                return;
+
+        LIST_REMOVE(addresses, address->network->addresses, address);
+
+        free(address->label);
+        free(address);
+}
+
+int address_configure(Manager *manager, Address *address, Link *link) {
+        _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
+        int r;
+
+        r = sd_rtnl_message_addr_new(RTM_NEWADDR, link->ifindex,
+                        address->family, address->prefixlen,
+                        IFA_F_PERMANENT, RT_SCOPE_UNIVERSE, &req);
+        if (r < 0) {
+                log_error("Could not allocate RTM_NEWADDR message: %s",
+                          strerror(-r));
+                return r;
+        }
+
+        r = sd_rtnl_message_append(req, IFA_LOCAL, &address->in_addr);
+        if (r < 0) {
+                log_error("Could not append IFA_LOCAL attribute: %s",
+                          strerror(-r));
+                return r;
+        }
+
+        if (address->family == AF_INET) {
+                struct in_addr broadcast;
+
+                broadcast.s_addr = address->in_addr.in.s_addr |
+                                   htonl(0xfffffffflu >> address->prefixlen);
+
+                r = sd_rtnl_message_append(req, IFA_BROADCAST, &broadcast);
+                if (r < 0) {
+                        log_error("Could not append IFA_BROADCAST attribute: %s",
+                                  strerror(-r));
+                        return r;
+                }
+        }
+
+        if (address->label) {
+                r = sd_rtnl_message_append(req, IFA_LABEL, address->label);
+                if (r < 0) {
+                        log_error("Could not append IFA_LABEL attribute: %s",
+                                  strerror(-r));
+                        return r;
+                }
+        }
+
+        r = sd_rtnl_send_with_reply_and_block(manager->rtnl, req, 0, NULL);
+        if (r < 0) {
+                log_error("Could not configure address: %s", strerror(-r));
+                return r != -EEXIST ? r : 0;
+        }
+
+        log_info("Configured interface address");
+
+        return 0;
+}
+
+int config_parse_address(const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *section,
+                const char *lvalue,
+                int ltype,
+                const char *rvalue,
+                void *data,
+                void *userdata) {
+        _cleanup_address_free_ Address *n = NULL;
+        _cleanup_free_ char *address = NULL;
+        const char *e;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        r = address_new(userdata, &n);
+        if (r < 0)
+                return r;
+
+        /* Address=address/prefixlen */
+
+        /* prefixlen */
+        e = strchr(rvalue, '/');
+        if (e) {
+                unsigned i;
+                r = safe_atou(e + 1, &i);
+                if (r < 0) {
+                        log_syntax(unit, LOG_ERR, filename, line, EINVAL,
+                                   "Interface prefix length is invalid, "
+                                   "ignoring assignment: %s", e + 1);
+                        return 0;
+                }
+
+                n->prefixlen = (unsigned char) i;
+                address = strndup(rvalue, e - rvalue);
+                if (!address)
+                        return log_oom();
+        } else {
+                address = strdup(rvalue);
+                if (!address)
+                        return log_oom();
+        }
+
+        r = net_parse_inaddr(address, &n->family, &n->in_addr);
+        if (r < 0) {
+                log_syntax(unit, LOG_ERR, filename, line, EINVAL,
+                           "Address is invalid, ignoring assignment: %s", address);
+                return 0;
+        }
+
+        n = NULL;
+
+        return 0;
+}