From: Michael Tremer <michael.tremer@ipfire.org>
Date: Mon, 30 Mar 2026 14:26:36 +0000 (+0000)
Subject: daemon: Add a handler to fetch a nl80211 socket
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=6b6f72cf3a3013dfb02612b55a71194ecd072f0a;p=telemetry.git

daemon: Add a handler to fetch a nl80211 socket

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

diff --git a/src/daemon/daemon.c b/src/daemon/daemon.c
index 2d116a5..9291997 100644
--- a/src/daemon/daemon.c
+++ b/src/daemon/daemon.c
@@ -27,6 +27,10 @@
 #include <systemd/sd-event.h>
 
 #ifdef HAVE_LIBNL3
+# ifdef HAVE_LIBNL3_GENL
+#  include <netlink/genl/ctrl.h>
+#  include <netlink/genl/genl.h>
+# endif
 # ifdef HAVE_LIBNL3_ROUTE
 #  include <netlink/route/route.h>
 #  include <netlink/socket.h>
@@ -82,11 +86,17 @@ struct td_daemon {
 
 	// Netlink Sockets
 #ifdef HAVE_LIBNL3
-# ifdef HAVE_LIBNL3_ROUTE
 	struct {
+		// 802.11
+# ifdef HAVE_LIBNL3_GENL
+		struct nl_sock* nl80211;
+# endif /* HAVE_LIBNL3_GENL */
+
+		// Route
+# ifdef HAVE_LIBNL3_ROUTE
 		struct nl_sock* route;
-	} nl_sockets;
 # endif /* HAVE_LIBNL3_ROUTE */
+	} nl_sockets;
 #endif /* HAVE_LIBNL3 */
 };
 
@@ -279,6 +289,10 @@ static int td_daemon_setup_udev(td_daemon* self) {
 static void td_daemon_free(td_daemon* self) {
 	// Free Netlink Sockets
 #ifdef HAVE_LIBNL3
+# ifdef HAVE_LIBNL3_GENL
+	if (self->nl_sockets.nl80211)
+		nl_socket_free(self->nl_sockets.nl80211);
+# endif /* HAVE_LIBNL3_GENL */
 # ifdef HAVE_LIBNL3_ROUTE
 	if (self->nl_sockets.route)
 		nl_socket_free(self->nl_sockets.route);
@@ -438,38 +452,75 @@ int td_daemon_flush_source(
 }
 
 #ifdef HAVE_LIBNL3
-# ifdef HAVE_LIBNL3_ROUTE
-struct nl_sock* td_daemon_get_nl_route_socket(td_daemon* self) {
+static struct nl_sock* td_daemon_get_nl_socket(td_daemon* self, int protocol) {
+	struct nl_sock* sock = NULL;
+	int r;
+
+	// Allocate a new socket
+	sock = nl_socket_alloc();
+	if (!sock) {
+		ERROR(self->ctx, "Failed to allocate a new Netlink socket: %m\n");
+		goto ERROR;
+	}
+
+	// Connect the protocol
+	r = nl_connect(sock, protocol);
+	if (r < 0) {
+		ERROR(self->ctx, "Failed to select netlink protocol %d: %s\n",
+				protocol, nl_geterror(r));
+		errno = ENOTSUP;
+		goto ERROR;
+	}
+
+	// Return the socket
+	return sock;
+
+ERROR:
+	if (sock)
+		nl_socket_free(sock);
+
+	return NULL;
+}
+
+# ifdef HAVE_LIBNL3_GENL
+struct nl_sock* td_daemon_get_nl_80211_socket(td_daemon* self) {
+	struct nl_sock* sock = NULL;
 	int r;
 
 	// Create socket if not already done
-	if (!self->nl_sockets.route) {
-		// Allocate a new socket
-		self->nl_sockets.route = nl_socket_alloc();
-		if (!self->nl_sockets.route) {
-			ERROR(self->ctx, "Failed to allocate a new Netlink socket: %m\n");
-			goto ERROR;
-		}
+	if (!self->nl_sockets.nl80211) {
+		sock = td_daemon_get_nl_socket(self, NETLINK_GENERIC);
 
-		// Select routing
-		r = nl_connect(self->nl_sockets.route, NETLINK_ROUTE);
+		// Resolve 802.11
+		r = genl_ctrl_resolve(sock, "nl80211");
 		if (r < 0) {
-			ERROR(self->ctx, "Failed to select routing: %s\n", nl_geterror(r));
+			ERROR(self->ctx, "Failed to resolve nl80211: %s\n", nl_geterror(r));
 			errno = ENOTSUP;
 			goto ERROR;
 		}
+
+		// Store the socket
+		self->nl_sockets.nl80211 = sock;
 	}
 
-	return self->nl_sockets.route;
+	return self->nl_sockets.nl80211;
 
 ERROR:
-	if (self->nl_sockets.route) {
-		nl_socket_free(self->nl_sockets.route);
-		self->nl_sockets.route = NULL;
-	}
+	if (sock)
+		nl_socket_free(sock);
 
 	return NULL;
 }
+# endif /* HAVE_LIBNL3_GENL */
+
+# ifdef HAVE_LIBNL3_ROUTE
+struct nl_sock* td_daemon_get_nl_route_socket(td_daemon* self) {
+	// Create socket if not already done
+	if (!self->nl_sockets.route)
+		self->nl_sockets.route = td_daemon_get_nl_socket(self, NETLINK_ROUTE);
+
+	return self->nl_sockets.route;
+}
 # endif /* HAVE_LIBNL3_ROUTE */
 #endif /* HAVE_LIBNL3 */
 
diff --git a/src/daemon/daemon.h b/src/daemon/daemon.h
index 574af63..64ab376 100644
--- a/src/daemon/daemon.h
+++ b/src/daemon/daemon.h
@@ -59,6 +59,10 @@ int td_daemon_flush_source(
 	td_daemon* self, td_source* source, const char* object);
 
 #ifdef HAVE_LIBNL3
+# ifdef HAVE_LIBNL3_GENL
+struct nl_sock* td_daemon_get_nl_80211_socket(td_daemon* self);
+# endif /* HAVE_LIBNL3_GENL */
+
 # ifdef HAVE_LIBNL3_ROUTE
 struct nl_sock* td_daemon_get_nl_route_socket(td_daemon* self);
 # endif /* HAVE_LIBNL3_ROUTE */