Remove the netlink code to get the tun if index.

It only worked for kernel >= 2.6.33. Use if_nametoindex() instead, which made
me include net/if.h in place of linux/if.h. Also, fix the RTM_SETLINK use which
should really be RTM_NEWLINK with correct parameters.

Signed-off-by: Benjamin Cama <benoar@dolka.fr>

diff --git a/l2tpns.c b/l2tpns.c
index c34dc63..5545aed 100644 (file)
--- a/l2tpns.c
+++ b/l2tpns.c
@@ -30,7 +30,7 @@ char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.176 2011/01/20 12:48:40 bodea Exp
 #include <sys/time.h>
 #include <sys/resource.h>
 #include <sys/wait.h>
-#include <linux/if.h>
+#include <net/if.h>
 #include <stddef.h>
 #include <time.h>
 #include <dlfcn.h>
@@ -641,7 +641,6 @@ static char *tun_nl_phase_msg[] = {
 // Set up TUN interface
 static void inittun(void)
 {
-       struct ifinfomsg ifinfo;
        struct ifreq ifr;
 
        memset(&ifr, 0, sizeof(ifr));
@@ -665,41 +664,13 @@ static void inittun(void)
        assert(strlen(ifr.ifr_name) < sizeof(config->tundevice) - 1);
        strncpy(config->tundevice, ifr.ifr_name, sizeof(config->tundevice));
 
+       tunidx = if_nametoindex(config->tundevice);
+       if (tunidx == 0)
        {
-               // get the interface index
-               struct {
-                       struct nlmsghdr nh;
-                       struct ifinfomsg ifinfo;
-               } req;
-               char buf[4096];
-               ssize_t len;
-               struct nlmsghdr *resp_nh;
-
-               req.nh.nlmsg_type = RTM_GETLINK;
-               req.nh.nlmsg_flags = NLM_F_REQUEST;
-               req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifinfo));
-
-               req.ifinfo.ifi_family = AF_UNSPEC; // as the man says
-
-               netlink_addattr(&req.nh, IFLA_IFNAME, config->tundevice, strlen(config->tundevice)+1);
-
-               if(netlink_send(&req.nh) < 0 || (len = netlink_recv(buf, sizeof(buf))) < 0)
-               {
-                       LOG(0, 0, 0, "Error getting tun ifindex: %s\n", strerror(errno));
-                       exit(1);
-               }
-
-               resp_nh = (struct nlmsghdr *)buf;
-               if (!NLMSG_OK (resp_nh, len))
-               {
-                       LOG(0, 0, 0, "Malformed answer getting tun ifindex %ld\n", len);
-                       exit(1);
-               }
-
-               memcpy(&ifinfo, NLMSG_DATA(resp_nh), sizeof(ifinfo));
-               // got index
-               tunidx = ifinfo.ifi_index;
+               LOG(0, 0, 0, "Can't get tun interface index\n");
+               exit(1);
        }
+
        {
                struct {
                        // interface setting
@@ -715,11 +686,12 @@ static void inittun(void)
 
                memset(&req, 0, sizeof(req));
 
-               req.nh.nlmsg_type = RTM_SETLINK;
+               req.nh.nlmsg_type = RTM_NEWLINK;
                req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_MULTI;
                req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.ifmsg.ifinfo));
 
-               req.ifmsg.ifinfo = ifinfo;
+               req.ifmsg.ifinfo.ifi_family = AF_UNSPEC;
+               req.ifmsg.ifinfo.ifi_index = tunidx;
                req.ifmsg.ifinfo.ifi_flags |= IFF_UP; // set interface up
                req.ifmsg.ifinfo.ifi_change = IFF_UP; // only change this flag
 
@@ -742,7 +714,7 @@ static void inittun(void)
                req.ifmsg.ifaddr.ifa_family = AF_INET;
                req.ifmsg.ifaddr.ifa_prefixlen = 32;
                req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE;
-               req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
+               req.ifmsg.ifaddr.ifa_index = tunidx;
 
                if (config->bind_address)
                        ip = config->bind_address;
@@ -766,7 +738,7 @@ static void inittun(void)
                        req.ifmsg.ifaddr.ifa_family = AF_INET6;
                        req.ifmsg.ifaddr.ifa_prefixlen = 64;
                        req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_LINK;
-                       req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
+                       req.ifmsg.ifaddr.ifa_index = tunidx;
 
                        // Link local address is FE80::1
                        memset(&ip6, 0, sizeof(ip6));
@@ -787,7 +759,7 @@ static void inittun(void)
                        req.ifmsg.ifaddr.ifa_family = AF_INET6;
                        req.ifmsg.ifaddr.ifa_prefixlen = 64;
                        req.ifmsg.ifaddr.ifa_scope = RT_SCOPE_UNIVERSE;
-                       req.ifmsg.ifaddr.ifa_index = ifinfo.ifi_index;
+                       req.ifmsg.ifaddr.ifa_index = tunidx;
 
                        // Global address is prefix::1
                        ip6 = config->ipv6_prefix;