networkd: Add scaffolding to connect to dbus

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/Makefile.am b/Makefile.am
index abba6465a2bb657a0f725c1d53440e6191daebb4..60a1bcde84565e70ce92d53b9f82fa0959db8be2 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -304,6 +304,8 @@ sbin_PROGRAMS += \
        networkd
 
 dist_networkd_SOURCES = \
+       src/networkd/bus.c \
+       src/networkd/bus.h \
        src/networkd/daemon.c \
        src/networkd/daemon.h \
        src/networkd/logging.h \

diff --git a/src/networkd/bus.c b/src/networkd/bus.c
new file mode 100644 (file)
index 0000000..95862d2
--- /dev/null
+++ b/src/networkd/bus.c
@@ -0,0 +1,131 @@
+/*#############################################################################
+#                                                                             #
+# IPFire.org - A linux based firewall                                         #
+# Copyright (C) 2023 IPFire Network Development Team                          #
+#                                                                             #
+# This program is free software: you can redistribute it and/or modify        #
+# it under the terms of the GNU General Public License as published by        #
+# the Free Software Foundation, either version 3 of the License, or           #
+# (at your option) any later version.                                         #
+#                                                                             #
+# This program 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 General Public License for more details.                                #
+#                                                                             #
+# You should have received a copy of the GNU General Public License           #
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
+#                                                                             #
+#############################################################################*/
+
+#include <stdlib.h>
+#include <string.h>
+
+#include <systemd/sd-bus.h>
+#include <systemd/sd-event.h>
+
+#include "bus.h"
+#include "daemon.h"
+#include "logging.h"
+
+static int nw_bus_daemon_reload(sd_bus_message* m, void* data, sd_bus_error* ret_error) {
+       return 1;
+}
+
+static const sd_bus_vtable daemon_vtable[] = {
+        SD_BUS_VTABLE_START(0),
+        SD_BUS_METHOD("Reload", SD_BUS_NO_ARGS, SD_BUS_NO_RESULT,
+               nw_bus_daemon_reload, SD_BUS_VTABLE_UNPRIVILEGED),
+        SD_BUS_VTABLE_END,
+};
+
+int nw_bus_connect(sd_bus* bus, sd_event* loop) {
+       int r;
+
+       // Create a bus object
+       r = sd_bus_new(&bus);
+       if (r < 0) {
+               ERROR("Could not allocate a bus object: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Set description
+       r = sd_bus_set_description(bus, NETWORKD_BUS_DESCRIPTION);
+       if (r < 0) {
+               ERROR("Could not set bus description: %s\n", strerror(-r));
+               return 1;
+       }
+
+       const char* address = secure_getenv("DBUS_SYSTEM_BUS_ADDRESS");
+       if (!address)
+               address = DEFAULT_SYSTEM_BUS_ADDRESS;
+
+       // Set bus address
+       r = sd_bus_set_address(bus, address);
+       if (r < 0) {
+               ERROR("Could not set bus address: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Set bus client
+       r = sd_bus_set_bus_client(bus, 1);
+       if (r < 0) {
+               ERROR("Could not set bus client: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Request some credentials for all messages
+       r = sd_bus_negotiate_creds(bus, 1,
+                       SD_BUS_CREDS_UID|SD_BUS_CREDS_EUID|SD_BUS_CREDS_EFFECTIVE_CAPS);
+       if (r < 0) {
+               ERROR("Could not negotiate creds: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Automatically bind when the socket is available
+       r = sd_bus_set_watch_bind(bus, 1);
+       if (r < 0) {
+               ERROR("Could not watch socket: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Emit a connected signal when we are connected
+       r = sd_bus_set_connected_signal(bus, 1);
+       if (r < 0) {
+               ERROR("Could not enable sending a connect signal: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Connect to the bus
+       r = sd_bus_start(bus);
+       if (r < 0) {
+               ERROR("Could not connect to bus: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Register any functions
+       r = sd_bus_add_object_vtable(bus, NULL,
+               NETWORKD_BUS_OBJECT_PATH, NETWORKD_BUS_INTERFACE_NAME, daemon_vtable, NULL);
+       if (r < 0) {
+               ERROR("Could not add object vtable: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Request interface name
+       // XXX Should this be async?
+       // XXX How do we get the actual error message from dbus?
+       r = sd_bus_request_name(bus, NETWORKD_BUS_INTERFACE_NAME, 0);
+       if (r < 0) {
+               ERROR("Could not request bus name: %s\n", strerror(-r));
+               return 1;
+       }
+
+       // Attach the event loop
+       r = sd_bus_attach_event(bus, loop, 0);
+       if (r < 0) {
+               ERROR("Could not attach bus to event loop: %s\n", strerror(-r));
+               return 1;
+       }
+
+       return 0;
+}

diff --git a/src/networkd/bus.h b/src/networkd/bus.h
new file mode 100644 (file)
index 0000000..90c1556
--- /dev/null
+++ b/src/networkd/bus.h
@@ -0,0 +1,35 @@
+/*#############################################################################
+#                                                                             #
+# IPFire.org - A linux based firewall                                         #
+# Copyright (C) 2023 IPFire Network Development Team                          #
+#                                                                             #
+# This program is free software: you can redistribute it and/or modify        #
+# it under the terms of the GNU General Public License as published by        #
+# the Free Software Foundation, either version 3 of the License, or           #
+# (at your option) any later version.                                         #
+#                                                                             #
+# This program 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 General Public License for more details.                                #
+#                                                                             #
+# You should have received a copy of the GNU General Public License           #
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
+#                                                                             #
+#############################################################################*/
+
+#ifndef NETWORKD_BUS_H
+#define NETWORKD_BUS_H
+
+#define NETWORKD_BUS_DESCRIPTION               "networkd"
+#define NETWORKD_BUS_OBJECT_PATH               "/org/ipfire/network1"
+#define NETWORKD_BUS_INTERFACE_NAME            "org.ipfire.network1"
+
+#define DEFAULT_SYSTEM_BUS_ADDRESS             "unix:path=/run/dbus/system_bus_socket"
+
+#include <systemd/sd-bus.h>
+#include <systemd/sd-event.h>
+
+int nw_bus_connect(sd_bus* bus, sd_event* loop);
+
+#endif /* NETWORKD_BUS_H */

diff --git a/src/networkd/daemon.c b/src/networkd/daemon.c
index 98fb5bd55835dcc476ab2d25de8054273cdb650b..3aee8caf378c2fecf53cd5ade4fae4e5c610d495 100644 (file)
--- a/src/networkd/daemon.c
+++ b/src/networkd/daemon.c
@@ -22,8 +22,10 @@
 #include <stdlib.h>
 #include <string.h>
 
+#include <systemd/sd-bus.h>
 #include <systemd/sd-event.h>
 
+#include "bus.h"
 #include "daemon.h"
 #include "logging.h"
 
@@ -32,6 +34,9 @@ struct nw_daemon {
 
        // Event Loop
        sd_event* loop;
+
+       // DBus Connection
+       sd_bus* bus;
 };
 
 static int __nw_daemon_terminate(sd_event_source* source, const struct signalfd_siginfo* si,
@@ -105,6 +110,11 @@ static int nw_daemon_setup(struct nw_daemon* daemon) {
        if (r)
                return r;
 
+       // Connect to the system bus
+       r = nw_bus_connect(daemon->bus, daemon->loop);
+       if (r)
+               return r;
+
        return 0;
 }
 
@@ -135,6 +145,8 @@ ERROR:
 }
 
 static void nw_daemon_free(struct nw_daemon* daemon) {
+       if (daemon->bus)
+               sd_bus_unref(daemon->bus);
        if (daemon->loop)
                sd_event_unref(daemon->loop);