networkd: netdev - reduce chance of race when receiving netdev's ifindex

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

diff --git a/src/network/networkd-netdev.c b/src/network/networkd-netdev.c
index 2d1cef112bd86a52a6316a33b17fd9ae62786795..c0f3df5b66a5d1159ad49415676576e03ed94c5c 100644 (file)
--- a/src/network/networkd-netdev.c
+++ b/src/network/networkd-netdev.c
@@ -28,7 +28,8 @@
 
 static const char* const netdev_kind_table[] = {
         [NETDEV_KIND_BRIDGE] = "bridge",
-        [NETDEV_KIND_BOND] = "bond"
+        [NETDEV_KIND_BOND] = "bond",
+        [NETDEV_KIND_VLAN] = "vlan",
 };
 
 DEFINE_STRING_TABLE_LOOKUP(netdev_kind, NetdevKind);
@@ -97,7 +98,7 @@ static int netdev_enslave_ready(Netdev *netdev, Link* link, sd_rtnl_message_hand
                 return r;
         }
 
-        r = sd_rtnl_message_append_u32(req, IFLA_MASTER, netdev->link->ifindex);
+        r = sd_rtnl_message_append_u32(req, IFLA_MASTER, netdev->ifindex);
         if (r < 0) {
                 log_error_netdev(netdev,
                                  "Could not append IFLA_MASTER attribute: %s",
@@ -139,7 +140,7 @@ static int netdev_enter_ready(Netdev *netdev) {
 
 static int netdev_create_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata) {
         Netdev *netdev = userdata;
-        int r;
+        int r, ifindex;
 
         assert(netdev->state != _NETDEV_STATE_INVALID);
 
@@ -151,16 +152,24 @@ static int netdev_create_handler(sd_rtnl *rtnl, sd_rtnl_message *m, void *userda
                 return 1;
         }
 
+        r = sd_rtnl_message_link_get_ifindex(m, &ifindex);
+        if (r < 0)
+                log_warning_netdev(netdev, "created netdev with unknown ifindex: %s", strerror(-r));
+        else {
+                log_info_netdev(netdev, "created netdev with ifindex %d", ifindex);
+                netdev_set_ifindex(netdev, ifindex);
+        }
+
         return 1;
 }
 
-static int netdev_create(Netdev *netdev) {
+static int netdev_create(Netdev *netdev, Link *link, sd_rtnl_message_handler_t callback) {
         _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *req = NULL;
         const char *kind;
         int r;
 
         assert(netdev);
-        assert(netdev->state == _NETDEV_STATE_INVALID);
+        assert(!(netdev->kind == NETDEV_KIND_VLAN) || (link && callback && netdev->vlanid >= 0));
         assert(netdev->name);
         assert(netdev->manager);
         assert(netdev->manager->rtnl);
@@ -173,6 +182,16 @@ static int netdev_create(Netdev *netdev) {
                 return r;
         }
 
+        if (link) {
+                r = sd_rtnl_message_append_u32(req, IFLA_LINK, link->ifindex);
+                if (r < 0) {
+                        log_error_netdev(netdev,
+                                         "Could not append IFLA_LINK attribute: %s",
+                                         strerror(-r));
+                        return r;
+                }
+        }
+
         r = sd_rtnl_message_append_string(req, IFLA_IFNAME, netdev->name);
         if (r < 0) {
                 log_error_netdev(netdev,
@@ -203,6 +222,32 @@ static int netdev_create(Netdev *netdev) {
                 return r;
         }
 
+        if (netdev->vlanid >= 0) {
+                r = sd_rtnl_message_open_container(req, IFLA_INFO_DATA);
+                if (r < 0) {
+                        log_error_netdev(netdev,
+                                         "Could not open IFLA_INFO_DATA container: %s",
+                                         strerror(-r));
+                        return r;
+                }
+
+                r = sd_rtnl_message_append_u16(req, IFLA_VLAN_ID, netdev->vlanid);
+                if (r < 0) {
+                        log_error_netdev(netdev,
+                                         "Could not append IFLA_VLAN_ID attribute: %s",
+                                         strerror(-r));
+                        return r;
+                }
+
+                r = sd_rtnl_message_close_container(req);
+                if (r < 0) {
+                        log_error_netdev(netdev,
+                                         "Could not close IFLA_INFO_DATA container %s",
+                                         strerror(-r));
+                        return r;
+                }
+        }
+
         r = sd_rtnl_message_close_container(req);
         if (r < 0) {
                 log_error_netdev(netdev,
@@ -211,7 +256,10 @@ static int netdev_create(Netdev *netdev) {
                 return r;
         }
 
-        r = sd_rtnl_call_async(netdev->manager->rtnl, req, &netdev_create_handler, netdev, 0, NULL);
+        if (link)
+                r = sd_rtnl_call_async(netdev->manager->rtnl, req, callback, link, 0, NULL);
+        else
+                r = sd_rtnl_call_async(netdev->manager->rtnl, req, &netdev_create_handler, netdev, 0, NULL);
         if (r < 0) {
                 log_error_netdev(netdev,
                                  "Could not send rtnetlink message: %s", strerror(-r));
@@ -226,6 +274,9 @@ static int netdev_create(Netdev *netdev) {
 }
 
 int netdev_enslave(Netdev *netdev, Link *link, sd_rtnl_message_handler_t callback) {
+        if (netdev->kind == NETDEV_KIND_VLAN)
+                return netdev_create(netdev, link, callback);
+
         if (netdev->state == NETDEV_STATE_READY) {
                 netdev_enslave_ready(netdev, link, callback);
         } else {
@@ -245,21 +296,18 @@ int netdev_enslave(Netdev *netdev, Link *link, sd_rtnl_message_handler_t callbac
         return 0;
 }
 
-int netdev_set_link(Manager *m, NetdevKind kind, Link *link) {
-        Netdev *netdev;
-        int r;
-
-        r = netdev_get(m, link->ifname, &netdev);
-        if (r < 0)
-                return r;
-
-        if (netdev->link && netdev->link != link)
-                return -EEXIST;
+int netdev_set_ifindex(Netdev *netdev, int ifindex) {
+        assert(netdev);
+        assert(ifindex > 0);
 
-        if (netdev->kind != kind)
-                return -EINVAL;
+        if (netdev->ifindex > 0) {
+                if (netdev->ifindex == ifindex)
+                        return 0;
+                else
+                        return -EEXIST;
+        }
 
-        netdev->link = link;
+        netdev->ifindex = ifindex;
 
         netdev_enter_ready(netdev);
 
@@ -289,8 +337,9 @@ static int netdev_load_one(Manager *manager, const char *filename) {
         netdev->manager = manager;
         netdev->state = _NETDEV_STATE_INVALID;
         netdev->kind = _NETDEV_KIND_INVALID;
+        netdev->vlanid = -1;
 
-        r = config_parse(NULL, filename, file, "Netdev\0", config_item_perf_lookup,
+        r = config_parse(NULL, filename, file, "Netdev\0VLAN\0", config_item_perf_lookup,
                         (void*) network_gperf_lookup, false, false, netdev);
         if (r < 0) {
                 log_warning("Could not parse config file %s: %s", filename, strerror(-r));
@@ -307,6 +356,11 @@ static int netdev_load_one(Manager *manager, const char *filename) {
                 return 0;
         }
 
+        if (netdev->kind == NETDEV_KIND_VLAN && netdev->vlanid < 0) {
+                log_warning("VLAN without Id configured in %s. Ignoring", filename);
+                return 0;
+        }
+
         netdev->filename = strdup(filename);
         if (!netdev->filename)
                 return log_oom();
@@ -317,9 +371,11 @@ static int netdev_load_one(Manager *manager, const char *filename) {
 
         LIST_HEAD_INIT(netdev->callbacks);
 
-        r = netdev_create(netdev);
-        if (r < 0)
-                return r;
+        if (netdev->kind != NETDEV_KIND_VLAN) {
+                r = netdev_create(netdev, NULL, NULL);
+                if (r < 0)
+                        return r;
+        }
 
         netdev = NULL;