core: Use interface index instead of interface name

Service and network code use only interface indexes. Convert the rest of
the code using interface names to use interface indexes instead. The files
affected are:
   include/resolver.h
   src/connman.h
   src/dnsproxy.c
   src/resolver.c
   src/rtnl.c
   src/service.c
   src/tethering.c

As the network and service code used interface indexes, the interface
name had to be looked up via a SIOCGIFNAME ioctl when needed. If a service
was removed due to the interface and network being taken down, the lookup
wouldn't work. This caused DNS servers to be left behind with broken sockets
since removing the DNS servers was done using the interface name.

1 files changed, 6 insertions, 11 deletions

diff --git a/src/rtnl.c b/src/rtnl.c
index 5f3fe155..915654bc 100644
--- a/src/rtnl.c
+++ b/src/rtnl.c
@@ -611,11 +611,7 @@ static void process_newaddr(unsigned char family, unsigned char prefixlen,
 		 * have now properly configured interface with proper
 		 * autoconfigured address.
 		 */
-		char *interface = connman_inet_ifname(index);
-
-		__connman_resolver_redo_servers(interface);
-
-		g_free(interface);
+		__connman_resolver_redo_servers(index);
 	}
 }
 
@@ -1195,7 +1191,7 @@ static void rtnl_newnduseropt(struct nlmsghdr *hdr)
 	struct in6_addr *servers = NULL;
 	int i, nr_servers = 0;
 	int msglen = msg->nduseropt_opts_len;
-	char *interface;
+	int index;
 
 	DBG("family %d index %d len %d type %d code %d",
 		msg->nduseropt_family, msg->nduseropt_ifindex,
@@ -1207,8 +1203,8 @@ static void rtnl_newnduseropt(struct nlmsghdr *hdr)
 			msg->nduseropt_icmp_code != 0)
 		return;
 
-	interface = connman_inet_ifname(msg->nduseropt_ifindex);
-	if (!interface)
+	index = msg->nduseropt_ifindex;
+	if (index < 0)
 		return;
 
 	for (opt = (void *)&msg[1];
@@ -1229,7 +1225,7 @@ static void rtnl_newnduseropt(struct nlmsghdr *hdr)
 								sizeof(buf)))
 					continue;
 
-				connman_resolver_append_lifetime(interface,
+				connman_resolver_append_lifetime(index,
 							NULL, buf, lifetime);
 			}
 
@@ -1238,13 +1234,12 @@ static void rtnl_newnduseropt(struct nlmsghdr *hdr)
 
 			domains = rtnl_nd_opt_dnssl(opt, &lifetime);
 			for (i = 0; domains != NULL && domains[i] != NULL; i++)
-				connman_resolver_append_lifetime(interface,
+				connman_resolver_append_lifetime(index,
 						domains[i], NULL, lifetime);
 		}
 	}
 
 	g_free(domains);
-	g_free(interface);
 }
 
 static const char *type2string(uint16_t type)