udevd: get netlink socket from systemd

1 files changed, 81 insertions, 17 deletions

diff --git a/udev/udevd.c b/udev/udevd.c
index dbb1e16004..b30a27bf71 100644
--- a/udev/udevd.c
+++ b/udev/udevd.c
@@ -1099,6 +1099,42 @@ static int convert_db(struct udev *udev)
 	return 0;
 }
 
+static int systemd_fds(struct udev *udev, int *rctrl, int *rnetlink)
+{
+	int ctrl = -1, netlink = -1;
+	int fd, n;
+
+	n = sd_listen_fds(true);
+	if (n <= 0)
+		return -1;
+
+	for (fd = SD_LISTEN_FDS_START; fd < n + SD_LISTEN_FDS_START; fd++) {
+		if (sd_is_socket(fd, AF_LOCAL, SOCK_SEQPACKET, -1)) {
+			if (ctrl >= 0)
+				return -1;
+			ctrl = fd;
+			continue;
+		}
+
+		if (sd_is_socket(fd, AF_NETLINK, SOCK_RAW, -1)) {
+			if (netlink >= 0)
+				return -1;
+			netlink = fd;
+			continue;
+		}
+
+		return -1;
+	}
+
+	if (ctrl < 0 || netlink < 0)
+		return -1;
+
+	info(udev, "ctrl=%i netlink=%i\n", ctrl, netlink);
+	*rctrl = ctrl;
+	*rnetlink = netlink;
+	return 0;
+}
+
 int main(int argc, char *argv[])
 {
 	struct udev *udev;
@@ -1277,34 +1313,57 @@ int main(int argc, char *argv[])
 		}
 	}
 
-	/* udevadm control socket */
-	if (sd_listen_fds(true) == 1 && sd_is_socket(SD_LISTEN_FDS_START, AF_LOCAL, SOCK_SEQPACKET, -1))
-		udev_ctrl = udev_ctrl_new_from_fd(udev, SD_LISTEN_FDS_START);
-	else
+	if (systemd_fds(udev, &fd_ctrl, &fd_netlink) >= 0) {
+		/* get control and netlink socket from from systemd */
+		udev_ctrl = udev_ctrl_new_from_socket_fd(udev, UDEV_CTRL_SOCK_PATH, fd_ctrl);
+		if (udev_ctrl == NULL) {
+			err(udev, "error taking over udev control socket");
+			rc = 1;
+			goto exit;
+		}
+
+		monitor = udev_monitor_new_from_netlink_fd(udev, "kernel", fd_netlink);
+		if (monitor == NULL) {
+			err(udev, "error taking over netlink socket\n");
+			rc = 3;
+			goto exit;
+		}
+	} else {
+		/* open control and netlink socket */
 		udev_ctrl = udev_ctrl_new_from_socket(udev, UDEV_CTRL_SOCK_PATH);
-	if (udev_ctrl == NULL) {
-		fprintf(stderr, "error initializing udev control socket");
-		err(udev, "error initializing udev control socket");
-		rc = 1;
+		if (udev_ctrl == NULL) {
+			fprintf(stderr, "error initializing udev control socket");
+			err(udev, "error initializing udev control socket");
+			rc = 1;
+			goto exit;
+		}
+		fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
+
+		monitor = udev_monitor_new_from_netlink(udev, "kernel");
+		if (monitor == NULL) {
+			fprintf(stderr, "error initializing netlink socket\n");
+			err(udev, "error initializing netlink socket\n");
+			rc = 3;
+			goto exit;
+		}
+		fd_netlink = udev_monitor_get_fd(monitor);
+	}
+
+	if (udev_monitor_enable_receiving(monitor) < 0) {
+		fprintf(stderr, "error binding netlink socket\n");
+		err(udev, "error binding netlink socket\n");
+		rc = 3;
 		goto exit;
 	}
+
 	if (udev_ctrl_enable_receiving(udev_ctrl) < 0) {
 		fprintf(stderr, "error binding udev control socket\n");
 		err(udev, "error binding udev control socket\n");
 		rc = 1;
 		goto exit;
 	}
-	fd_ctrl = udev_ctrl_get_fd(udev_ctrl);
 
-	monitor = udev_monitor_new_from_netlink(udev, "kernel");
-	if (monitor == NULL || udev_monitor_enable_receiving(monitor) < 0) {
-		fprintf(stderr, "error initializing netlink socket\n");
-		err(udev, "error initializing netlink socket\n");
-		rc = 3;
-		goto exit;
-	}
 	udev_monitor_set_receive_buffer_size(monitor, 128*1024*1024);
-	fd_netlink = udev_monitor_get_fd(monitor);
 
 	if (daemonize) {
 		pid_t pid;
@@ -1428,18 +1487,23 @@ int main(int argc, char *argv[])
 	memset(&ep_ctrl, 0, sizeof(struct epoll_event));
 	ep_ctrl.events = EPOLLIN;
 	ep_ctrl.data.fd = fd_ctrl;
+
 	memset(&ep_inotify, 0, sizeof(struct epoll_event));
 	ep_inotify.events = EPOLLIN;
 	ep_inotify.data.fd = fd_inotify;
+
 	memset(&ep_signal, 0, sizeof(struct epoll_event));
 	ep_signal.events = EPOLLIN;
 	ep_signal.data.fd = fd_signal;
+
 	memset(&ep_netlink, 0, sizeof(struct epoll_event));
 	ep_netlink.events = EPOLLIN;
 	ep_netlink.data.fd = fd_netlink;
+
 	memset(&ep_worker, 0, sizeof(struct epoll_event));
 	ep_worker.events = EPOLLIN;
 	ep_worker.data.fd = fd_worker;
+
 	fd_ep = epoll_create1(EPOLL_CLOEXEC);
 	if (fd_ep < 0) {
 		err(udev, "error creating epoll fd: %m\n");