udev: link-config - let udevd set the ifname

6 files changed, 62 insertions, 29 deletions

diff --git a/src/libsystemd-rtnl/rtnl-util.c b/src/libsystemd-rtnl/rtnl-util.c
index bf6bf27bb4..93804bb744 100644
--- a/src/libsystemd-rtnl/rtnl-util.c
+++ b/src/libsystemd-rtnl/rtnl-util.c
@@ -25,25 +25,43 @@
 
 #include "rtnl-util.h"
 
-int rtnl_set_link_properties(sd_rtnl *rtnl, int ifindex, const char *name, const struct ether_addr *mac, unsigned mtu) {
-        _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *message;
-        bool need_update = false;
+int rtnl_set_link_name(sd_rtnl *rtnl, int ifindex, const char *name) {
+        _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *message = NULL;
         int r;
 
         assert(rtnl);
         assert(ifindex > 0);
+        assert(name);
 
         r = sd_rtnl_message_link_new(RTM_NEWLINK, ifindex, 0, 0, &message);
         if (r < 0)
                 return r;
 
-        if (name) {
-                r = sd_rtnl_message_append(message, IFLA_IFNAME, name);
-                if (r < 0)
-                        return r;
+        r = sd_rtnl_message_append(message, IFLA_IFNAME, name);
+        if (r < 0)
+                return r;
 
-                need_update = true;
-        }
+        r = sd_rtnl_send_with_reply_and_block(rtnl, message, 0, NULL);
+        if (r < 0)
+                return r;
+
+        return 0;
+}
+
+int rtnl_set_link_properties(sd_rtnl *rtnl, int ifindex, const struct ether_addr *mac, unsigned mtu) {
+        _cleanup_sd_rtnl_message_unref_ sd_rtnl_message *message = NULL;
+        bool need_update = false;
+        int r;
+
+        assert(rtnl);
+        assert(ifindex > 0);
+
+        if (!mac && mtu == 0)
+                return 0;
+
+        r = sd_rtnl_message_link_new(RTM_NEWLINK, ifindex, 0, 0, &message);
+        if (r < 0)
+                return r;
 
         if (mac) {
                 r = sd_rtnl_message_append(message, IFLA_ADDRESS, mac);
diff --git a/src/libsystemd-rtnl/rtnl-util.h b/src/libsystemd-rtnl/rtnl-util.h
index dd8300b827..a6ac4b62c9 100644
--- a/src/libsystemd-rtnl/rtnl-util.h
+++ b/src/libsystemd-rtnl/rtnl-util.h
@@ -23,4 +23,5 @@
 
 #include "sd-rtnl.h"
 
-int rtnl_set_link_properties(sd_rtnl *rtnl, int ifindex, const char *name, const struct ether_addr *mac, unsigned mtu);
+int rtnl_set_link_name(sd_rtnl *rtnl, int ifindex, const char *name);
+int rtnl_set_link_properties(sd_rtnl *rtnl, int ifindex, const struct ether_addr *mac, unsigned mtu);
diff --git a/src/udev/net/link-config.c b/src/udev/net/link-config.c
index cf966bfe37..80f8b16f54 100644
--- a/src/udev/net/link-config.c
+++ b/src/udev/net/link-config.c
@@ -280,8 +280,10 @@ static bool enable_name_policy(void) {
         }
 
         FOREACH_WORD_QUOTED(w, l, line, state)
-                if (strneq(w, "net.ifnames=0", l))
+                if (strneq(w, "net.ifnames=0", l)) {
+                        log_info("Link name policy disabled on kernel commandline, ignoring.");
                         return false;
+                }
 
         return true;
 }
@@ -365,40 +367,45 @@ static int get_mac(struct udev_device *device, bool want_random, struct ether_ad
         return 0;
 }
 
-int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_device *device) {
-        const char *name;
+int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_device *device, const char **name) {
+        const char *old_name;
         const char *new_name = NULL;
         struct ether_addr generated_mac;
         struct ether_addr *mac = NULL;
         int r, ifindex;
 
+        assert(ctx);
+        assert(config);
+        assert(device);
+        assert(name);
+
         r = link_config_ctx_connect(ctx);
         if (r < 0)
                 return r;
 
-        name = udev_device_get_sysname(device);
-        if (!name)
+        old_name = udev_device_get_sysname(device);
+        if (!old_name)
                 return -EINVAL;
 
-        log_info("Configuring %s", name);
+        log_info("Configuring %s", old_name);
 
         if (config->description) {
                 r = udev_device_set_sysattr_value(device, "ifalias",
                                                   config->description);
                 if (r < 0)
                         log_warning("Could not set description of %s to '%s': %s",
-                                    name, config->description, strerror(-r));
+                                    old_name, config->description, strerror(-r));
         }
 
-        r = ethtool_set_speed(ctx->ethtool_fd, name, config->speed, config->duplex);
+        r = ethtool_set_speed(ctx->ethtool_fd, old_name, config->speed, config->duplex);
         if (r < 0)
                 log_warning("Could not set speed or duplex of %s to %u Mbytes (%s): %s",
-                             name, config->speed, duplex_to_string(config->duplex), strerror(-r));
+                             old_name, config->speed, duplex_to_string(config->duplex), strerror(-r));
 
-        r = ethtool_set_wol(ctx->ethtool_fd, name, config->wol);
+        r = ethtool_set_wol(ctx->ethtool_fd, old_name, config->wol);
         if (r < 0)
                 log_warning("Could not set WakeOnLan of %s to %s: %s",
-                            name, wol_to_string(config->wol), strerror(-r));
+                            old_name, wol_to_string(config->wol), strerror(-r));
 
         ifindex = udev_device_get_ifindex(device);
         if (ifindex <= 0) {
@@ -429,9 +436,12 @@ int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_dev
                 }
         }
 
-        if (!new_name && config->name) {
-                new_name = config->name;
-        }
+        if (new_name)
+                *name = new_name; /* a name was set by a policy */
+        else if (config->name)
+                *name = config->name; /* a name was set manually in the config */
+        else
+                *name = NULL;
 
         switch (config->mac_policy) {
                 case MACPOLICY_PERSISTENT:
@@ -454,9 +464,9 @@ int link_config_apply(link_config_ctx *ctx, link_config *config, struct udev_dev
                         mac = config->mac;
         }
 
-        r = rtnl_set_link_properties(ctx->rtnl, ifindex, new_name, mac, config->mtu);
+        r = rtnl_set_link_properties(ctx->rtnl, ifindex, mac, config->mtu);
         if (r < 0) {
-                log_warning("Could not set Name, MACAddress or MTU on %s: %s", name, strerror(-r));
+                log_warning("Could not set MACAddress or MTU on %s: %s", old_name, strerror(-r));
                 return r;
         }
 
diff --git a/src/udev/net/link-config.h b/src/udev/net/link-config.h
index f5dee5a274..b3ee81fdaa 100644
--- a/src/udev/net/link-config.h
+++ b/src/udev/net/link-config.h
@@ -74,7 +74,7 @@ int link_config_load(link_config_ctx *ctx);
 bool link_config_should_reload(link_config_ctx *ctx);
 
 int link_config_get(link_config_ctx *ctx, struct udev_device *device, struct link_config **ret);
-int link_config_apply(link_config_ctx *ctx, struct link_config *config, struct udev_device *device);
+int link_config_apply(link_config_ctx *ctx, struct link_config *config, struct udev_device *device, const char **name);
 
 const char *name_policy_to_string(NamePolicy p) _const_;
 NamePolicy name_policy_from_string(const char *p) _pure_;
diff --git a/src/udev/udev-builtin-net_setup_link.c b/src/udev/udev-builtin-net_setup_link.c
index 6a98b802b2..e6ffa53400 100644
--- a/src/udev/udev-builtin-net_setup_link.c
+++ b/src/udev/udev-builtin-net_setup_link.c
@@ -26,6 +26,7 @@
 link_config_ctx *ctx;
 
 static int builtin_net_setup_link(struct udev_device *dev, int argc, char **argv, bool test) {
+        const char *name;
         link_config *link;
         int r;
 
@@ -45,12 +46,15 @@ static int builtin_net_setup_link(struct udev_device *dev, int argc, char **argv
                 }
         }
 
-        r = link_config_apply(ctx, link, dev);
+        r = link_config_apply(ctx, link, dev, &name);
         if (r < 0) {
                 log_error("Could not apply link config to %s", udev_device_get_sysname(dev));
                 return EXIT_FAILURE;
         }
 
+        if (name)
+                udev_builtin_add_property(dev, test, "ID_NET_NAME", name);
+
         return EXIT_SUCCESS;
 }
 
diff --git a/src/udev/udev-event.c b/src/udev/udev-event.c
index bdf3a386c9..1242db9ef3 100644
--- a/src/udev/udev-event.c
+++ b/src/udev/udev-event.c
@@ -764,7 +764,7 @@ static int rename_netif(struct udev_event *event)
         if (r < 0)
                 return r;
 
-        r = rtnl_set_link_properties(rtnl, udev_device_get_ifindex(dev), name, NULL, 0);
+        r = rtnl_set_link_name(rtnl, udev_device_get_ifindex(dev), name);
         if (r < 0)
                 log_error("error changing net interface name %s to %s: %s",
                           oldname, name, strerror(-r));