1 files changed, 131 insertions, 2 deletions

diff --git a/libc/inet/if_index.c b/libc/inet/if_index.c
index dfddbc0d4..40e46d538 100644
--- a/libc/inet/if_index.c
+++ b/libc/inet/if_index.c
@@ -36,6 +36,8 @@
 #include <sys/ioctl.h>
 #include <libc-internal.h>
 
+#include "netlinkaccess.h"
+
 extern int __opensock(void) attribute_hidden;
 
 unsigned int
@@ -78,7 +80,9 @@ if_freenameindex (struct if_nameindex *ifn)
     }
   free (ifn);
 }
+hidden_strong_alias(if_freenameindex,__if_freenameindex)
 
+#if !__ASSUME_NETLINK_SUPPORT
 struct if_nameindex *
 if_nameindex (void)
 {
@@ -157,6 +161,131 @@ if_nameindex (void)
   return idx;
 #endif
 }
+#else
+struct if_nameindex *
+if_nameindex (void)
+{
+  unsigned int nifs = 0;
+  struct netlink_handle nh = { 0, 0, 0, NULL, NULL };
+  struct if_nameindex *idx = NULL;
+  struct netlink_res *nlp;
+
+  if (__netlink_open (&nh) < 0)
+    return NULL;
+
+
+  /* Tell the kernel that we wish to get a list of all
+     active interfaces.  Collect all data for every interface.  */
+  if (__netlink_request (&nh, RTM_GETLINK) < 0)
+    goto exit_free;
+
+  /* Count the interfaces.  */
+  for (nlp = nh.nlm_list; nlp; nlp = nlp->next)
+    {
+      struct nlmsghdr *nlh;
+      size_t size = nlp->size;
+
+      if (nlp->nlh == NULL)
+	continue;
+
+      /* Walk through all entries we got from the kernel and look, which
+         message type they contain.  */
+      for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size))
+	{
+	  /* Check if the message is what we want.  */
+	  if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq)
+	    continue;
+
+	  if (nlh->nlmsg_type == NLMSG_DONE)
+	    break;		/* ok */
+
+	  if (nlh->nlmsg_type == RTM_NEWLINK)
+	    ++nifs;
+	}
+    }
+
+  idx = malloc ((nifs + 1) * sizeof (struct if_nameindex));
+  if (idx == NULL)
+    {
+    nomem:
+      __set_errno (ENOBUFS);
+      goto exit_free;
+    }
+
+  /* Add the interfaces.  */
+  nifs = 0;
+  for (nlp = nh.nlm_list; nlp; nlp = nlp->next)
+    {
+      struct nlmsghdr *nlh;
+      size_t size = nlp->size;
+
+      if (nlp->nlh == NULL)
+	continue;
+
+      /* Walk through all entries we got from the kernel and look, which
+         message type they contain.  */
+      for (nlh = nlp->nlh; NLMSG_OK (nlh, size); nlh = NLMSG_NEXT (nlh, size))
+	{
+	  /* Check if the message is what we want.  */
+	  if ((pid_t) nlh->nlmsg_pid != nh.pid || nlh->nlmsg_seq != nlp->seq)
+	    continue;
+
+	  if (nlh->nlmsg_type == NLMSG_DONE)
+	    break;		/* ok */
+
+	  if (nlh->nlmsg_type == RTM_NEWLINK)
+	    {
+	      struct ifinfomsg *ifim = (struct ifinfomsg *) NLMSG_DATA (nlh);
+	      struct rtattr *rta = IFLA_RTA (ifim);
+	      size_t rtasize = IFLA_PAYLOAD (nlh);
+
+	      idx[nifs].if_index = ifim->ifi_index;
+
+	      while (RTA_OK (rta, rtasize))
+		{
+		  char *rta_data = RTA_DATA (rta);
+		  size_t rta_payload = RTA_PAYLOAD (rta);
+
+		  if (rta->rta_type == IFLA_IFNAME)
+		    {
+		      idx[nifs].if_name = __strndup (rta_data, rta_payload);
+		      if (idx[nifs].if_name == NULL)
+			{
+			  idx[nifs].if_index = 0;
+			  __if_freenameindex (idx);
+			  idx = NULL;
+			  goto nomem;
+			}
+		      break;
+		    }
+
+		  rta = RTA_NEXT (rta, rtasize);
+		}
+
+	      ++nifs;
+	    }
+	}
+    }
+
+  idx[nifs].if_index = 0;
+  idx[nifs].if_name = NULL;
+
+ exit_free:
+  __netlink_free_handle (&nh);
+  __netlink_close (&nh);
+
+  return idx;
+}
+#endif
+hidden_strong_alias(if_nameindex,__if_nameindex)
+
+#if 0
+struct if_nameindex *
+if_nameindex (void)
+{
+  return (if_nameindex_netlink () != NULL ? : if_nameindex_ioctl ());
+}
+#endif
 
 char *
 if_indextoname (unsigned int ifindex, char *ifname)
@@ -194,7 +323,7 @@ if_indextoname (unsigned int ifindex, char *ifname)
   struct if_nameindex *p;
   char *result = NULL;
 
-  idx = if_nameindex();
+  idx = __if_nameindex();
 
   if (idx != NULL)
     {
@@ -205,7 +334,7 @@ if_indextoname (unsigned int ifindex, char *ifname)
 	    break;
 	  }
 
-      if_freenameindex (idx);
+      __if_freenameindex (idx);
 
       if (result == NULL)
 	__set_errno (ENXIO);