From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 10 Jun 2023 11:29:22 +0000 (+0000)
Subject: networkd: Handle any uevents for links
X-Git-Url: http://git.ipfire.org/?p=people%2Fms%2Fnetwork.git;a=commitdiff_plain;h=40e2c8ca02fae3d175e8d49498a3b3b443b1c6ef

networkd: Handle any uevents for links

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

diff --git a/src/networkd/devmon.c b/src/networkd/devmon.c
index 0a8c26d4..c751985c 100644
--- a/src/networkd/devmon.c
+++ b/src/networkd/devmon.c
@@ -20,8 +20,75 @@
 
 #include <systemd/sd-device.h>
 
+#include "daemon.h"
 #include "devmon.h"
+#include "logging.h"
+
+static int nw_daemon_handle_uevent_net(nw_daemon* daemon,
+		sd_device* device, sd_device_action_t action) {
+	nw_link* link = NULL;
+	int ifindex;
+	int r;
+
+	// Fetch ifindex
+	r = sd_device_get_ifindex(device, &ifindex);
+	if (r < 0) {
+		ERROR("Could not get ifindex from uevent: %s\n", strerror(-r));
+		goto ERROR;
+	}
+
+	// Fetch the link
+	link = nw_daemon_get_link_by_ifindex(daemon, ifindex);
+	if (!link) {
+		DEBUG("Could not fetch link %d, ignoring\n", ifindex);
+		r = 0;
+		goto ERROR;
+	}
+
+	// Let the link handle its uevent
+	r = nw_link_handle_uevent(link, device, action);
+
+ERROR:
+	if (link)
+		nw_link_unref(link);
+
+	return r;
+}
 
 int nw_devmon_handle_uevent(sd_device_monitor* monitor, sd_device* device, void* data) {
+	sd_device_action_t action;
+	const char* subsystem = NULL;
+	int r;
+
+	// Fetch daemon
+	nw_daemon* daemon = (nw_daemon*)data;
+
+	// Fetch action
+	r = sd_device_get_action(device, &action);
+	if (r < 0) {
+		WARNING("Could not get uevent action, ignoring: %s\n", strerror(-r));
+		return r;
+	}
+
+	// Fetch subsystem
+	r = sd_device_get_subsystem(device, &subsystem);
+	if (r < 0) {
+		ERROR("Could not get uevent subsystem, ignoring: %s\n", strerror(-r));
+		return r;
+	}
+
+	// Handle any links
+	if (strcmp(subsystem, "net") == 0) {
+		r = nw_daemon_handle_uevent_net(daemon, device, action);
+
+	} else {
+		DEBUG("Received an uevent for an unhandled subsystem '%s', ignoring\n", subsystem);
+		return 0;
+	}
+
+	// Log if something went wrong
+	if (r < 0)
+		ERROR("Failed processing uevent: %s\n", strerror(-r));
+
 	return 0;
 }
diff --git a/src/networkd/link.c b/src/networkd/link.c
index f172208e..b0d9e865 100644
--- a/src/networkd/link.c
+++ b/src/networkd/link.c
@@ -559,6 +559,25 @@ ERROR:
 	return r;
 }
 
+// uevent
+
+int nw_link_handle_uevent(nw_link* link, sd_device* device, sd_device_action_t action) {
+	// We need to remove or replace the stored device as it is now outdated
+	if (link->device) {
+		sd_device_unref(link->device);
+
+		// If the device has been removed, we remove its reference
+		if (action == SD_DEVICE_REMOVE)
+			link->device = NULL;
+
+		// Otherwise we just store the new one
+		else
+			link->device = sd_device_ref(device);
+	}
+
+	return 0;
+}
+
 // JSON
 
 static int nw_link_device_to_json(nw_link* link, struct json_object* o) {
diff --git a/src/networkd/link.h b/src/networkd/link.h
index 36c7d9dd..c2f7b7e6 100644
--- a/src/networkd/link.h
+++ b/src/networkd/link.h
@@ -23,6 +23,8 @@
 
 #include <linux/if_link.h>
 
+#include <systemd/sd-device.h>
+
 typedef struct nw_link nw_link;
 
 #include "daemon.h"
@@ -46,6 +48,9 @@ int nw_link_process(sd_netlink* rtnl, sd_netlink_message* message, void* data);
 
 int nw_link_destroy(nw_link* link);
 
+// uevent
+int nw_link_handle_uevent(nw_link* link, sd_device* device, sd_device_action_t action);
+
 // JSON
 int nw_link_to_json(nw_link* link, struct json_object* o);