network: check link state with link_is_ready_to_configure() before configuring DHCP client or friends

Otherwise, DHCP client or friends may started before link-layer properties,
e.g. MAC address, being configured or the link being activated.

src/network/netdev/l2tp-tunnel.c

@@ -292,7 +292,7 @@ static int l2tp_get_local_address(NetDev *netdev, union in_addr_union *ret) {
                 if (r < 0)
                         return r;
 
-                if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+                if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                         return -EBUSY;
         }
 
@@ -346,7 +346,7 @@ static int l2tp_get_local_address(NetDev *netdev, union in_addr_union *ret) {
                 return link_get_l2tp_local_address(link, t, ret);
 
         HASHMAP_FOREACH(link, netdev->manager->links_by_index) {
-                if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+                if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                         continue;
 
                 if (link_get_l2tp_local_address(link, t, ret) >= 0)

src/network/netdev/netdev-util.c

@@ -51,7 +51,7 @@ int link_get_local_address(
                 assert_not_reached();
         }
 
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return -EBUSY;
 
         SET_FOREACH(a, link->addresses) {

src/network/networkd-dhcp-server.c

@@ -539,13 +539,7 @@ static bool dhcp_server_is_ready_to_configure(Link *link) {
 
         assert(link);
 
-        if (!link->network)
-                return false;
-
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
-                return false;
-
-        if (link->set_flags_messages > 0)
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return false;
 
         if (!link_has_carrier(link))

src/network/networkd-dhcp4.c

@@ -1557,7 +1557,7 @@ static int dhcp4_process_request(Request *req, Link *link, void *userdata) {
 
         assert(link);
 
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return 0;
 
         r = dhcp4_configure_duid(link);

src/network/networkd-dhcp6.c

@@ -741,7 +741,7 @@ static int dhcp6_process_request(Request *req, Link *link, void *userdata) {
 
         assert(link);
 
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return 0;
 
         r = dhcp_configure_duid(link, link_get_dhcp6_duid(link));

src/network/networkd-ndisc.c

@@ -1099,7 +1099,7 @@ static int ndisc_process_request(Request *req, Link *link, void *userdata) {
 
         assert(link);
 
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return 0;
 
         r = ndisc_configure(link);

src/network/networkd-radv.c

@@ -549,7 +549,7 @@ static int radv_is_ready_to_configure(Link *link) {
         assert(link);
         assert(link->network);
 
-        if (!IN_SET(link->state, LINK_STATE_CONFIGURING, LINK_STATE_CONFIGURED))
+        if (!link_is_ready_to_configure(link, /* allow_unmanaged = */ false))
                 return false;
 
         if (in6_addr_is_null(&link->ipv6ll_address))