networkd: run as unpriviliged "systemd-network" user

[elogind.git] / src / network / networkd.c

diff --git a/src/network/networkd.c b/src/network/networkd.c
index 1d43361201222f20b3fc88c077b931254d3423e0..cd7dd3ca0f59ca67db4f9c527b6909bfbb174ab7 100644 (file)
--- a/src/network/networkd.c
+++ b/src/network/networkd.c
@@ -19,13 +19,17 @@
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 ***/
 
+#include "capability.h"
 #include "sd-event.h"
 #include "sd-daemon.h"
 
 #include "networkd.h"
 
 int main(int argc, char *argv[]) {
-        _cleanup_manager_free_ Manager *m;
+        _cleanup_manager_free_ Manager *m = NULL;
+        const char *user = "systemd-network";
+        uid_t uid;
+        gid_t gid;
         int r;
 
         log_set_target(LOG_TARGET_AUTO);
@@ -40,33 +44,83 @@ int main(int argc, char *argv[]) {
                 goto out;
         }
 
-        r = manager_new(&m);
-        if (r < 0)
+        r = get_user_creds(&user, &uid, &gid, NULL, NULL);
+        if (r < 0) {
+                log_error("Cannot resolve user name %s: %s", user, strerror(-r));
                 goto out;
+        }
 
-        r = manager_load_config(m);
+        /* Always create the directories people can create inotify
+         * watches in. */
+        r = mkdir_safe_label("/run/systemd/network", 0755, uid, gid);
         if (r < 0)
-                return EXIT_FAILURE;
+                log_error("Could not create runtime directory: %s",
+                          strerror(-r));
 
-        r = manager_udev_listen(m);
+        r = mkdir_safe_label("/run/systemd/network/links", 0755, uid, gid);
         if (r < 0)
-                goto out;
+                log_error("Could not create runtime directory 'links': %s",
+                          strerror(-r));
 
-        r = manager_udev_enumerate_links(m);
+        r = mkdir_safe_label("/run/systemd/network/leases", 0755, uid, gid);
+        if (r < 0)
+                log_error("Could not create runtime directory 'leases': %s",
+                          strerror(-r));
+
+        r = drop_privileges(uid, gid,
+                            (1ULL << CAP_NET_ADMIN) |
+                            (1ULL << CAP_NET_BIND_SERVICE) |
+                            (1ULL << CAP_NET_BROADCAST) |
+                            (1ULL << CAP_NET_RAW) |
+                            (1ULL << CAP_SYS_MODULE));
         if (r < 0)
                 goto out;
 
+        r = manager_new(&m);
+        if (r < 0) {
+                log_error("Could not create manager: %s", strerror(-r));
+                goto out;
+        }
+
+        r = manager_udev_listen(m);
+        if (r < 0) {
+                log_error("Could not connect to udev: %s", strerror(-r));
+                goto out;
+        }
+
         r = manager_rtnl_listen(m);
-        if (r < 0)
+        if (r < 0) {
+                log_error("Could not connect to rtnl: %s", strerror(-r));
+                goto out;
+        }
+
+        r = manager_bus_listen(m);
+        if (r < 0) {
+                log_error("Could not connect to system bus: %s", strerror(-r));
+                goto out;
+        }
+
+        r = manager_load_config(m);
+        if (r < 0) {
+                log_error("Could not load configuration files: %s", strerror(-r));
                 goto out;
+        }
+
+        r = manager_rtnl_enumerate_links(m);
+        if (r < 0) {
+                log_error("Could not enumerate links: %s", strerror(-r));
+                goto out;
+        }
 
         sd_notify(false,
                   "READY=1\n"
                   "STATUS=Processing requests...");
 
         r = sd_event_loop(m->event);
-        if (r < 0)
+        if (r < 0) {
+                log_error("Event loop failed: %s", strerror(-r));
                 goto out;
+        }
 
 out:
         sd_notify(false,