interface, system: clean up netns functionality

Use struct device pointer as parameter instead of bare ifname allows
for some simplication and again removing system_ifname_resolve()
function introduced in commit d93126d.

Fixes: d93126d ("interface: allow renaming interface when moving to jail netns")
Signed-off-by: Daniel Golle <daniel@makrotopia.org>

interface.c

@@ -1171,7 +1171,7 @@ interface_start_jail(const char *jail, const pid_t netns_pid)
 		if (!iface->jail || strcmp(iface->jail, jail))
 			continue;
 
-		system_link_netns_move(iface->ifname, netns_fd, iface->jail_ifname);
+		system_link_netns_move(iface->main_dev.dev, netns_fd, iface->jail_ifname);
 	}
 
 	close(netns_fd);
@@ -1248,7 +1248,7 @@ interface_stop_jail(const char *jail, const pid_t netns_pid)
 
 		interface_do_reload(iface);
 		interface_set_down(iface);
-		system_link_netns_move(iface->ifname, root_netns, orig_ifname);
+		system_link_netns_move(iface->main_dev.dev, root_netns, orig_ifname);
 	}
 
 	close(root_netns);

system-dummy.c

@@ -54,9 +54,9 @@ int system_bridge_delif(struct device *bridge, struct device *dev)
 	return 0;
 }
 
-int system_link_netns_move(const char *ifname, int netns_fd, const char *target_ifname)
+int system_link_netns_move(struct device *dev, int netns_fd, const char *target_ifname)
 {
-	D(SYSTEM, "ip link dev %s name %s netns %d\n", ifname, target_ifname, netns_fd);
+	D(SYSTEM, "ip link set %s name %s netns %d\n", dev->ifname, target_ifname, netns_fd);
 	return 0;
 }
 

system-linux.c

@@ -843,21 +843,16 @@ int system_bridge_delif(struct device *bridge, struct device *dev)
 	return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF, NULL);
 }
 
-static int system_ifname_resolve(const char *ifname)
+int system_if_resolve(struct device *dev)
 {
 	struct ifreq ifr;
-	strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name) - 1);
+	strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name) - 1);
 	if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
 		return ifr.ifr_ifindex;
 	else
 		return 0;
 }
 
-int system_if_resolve(struct device *dev)
-{
-	return system_ifname_resolve(dev->ifname);
-}
-
 static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
 {
 	struct ifreq ifr;
@@ -1251,14 +1246,17 @@ nla_put_failure:
 	return -ENOMEM;
 }
 
-int system_link_netns_move(const char *ifname, int netns_fd, const char *target_ifname)
+int system_link_netns_move(struct device *dev, int netns_fd, const char *target_ifname)
 {
 	struct nl_msg *msg;
 	struct ifinfomsg iim = {
 		.ifi_family = AF_UNSPEC,
 	};
 
-	iim.ifi_index = system_ifname_resolve(ifname);
+	if (!dev)
+		return -1;
+
+	iim.ifi_index = system_if_resolve(dev);
 	msg = nlmsg_alloc_simple(RTM_NEWLINK, NLM_F_REQUEST);
 
 	if (!msg)

system.h

@@ -243,7 +243,7 @@ void system_fd_set_cloexec(int fd);
 
 int system_update_ipv6_mtu(struct device *dev, int mtu);
 
-int system_link_netns_move(const char *ifname, const pid_t target_ns, const char *target_ifname);
+int system_link_netns_move(struct device *dev, const pid_t target_ns, const char *target_ifname);
 int system_netns_open(const pid_t target_ns);
 int system_netns_set(int netns_fd);