1 files changed, 97 insertions, 0 deletions
diff --git a/zebra/mtu_kvm.c b/zebra/mtu_kvm.c
new file mode 100644
index 000000000..3731dab67
--- /dev/null
+++ b/zebra/mtu_kvm.c
@@ -0,0 +1,97 @@
+/* MTU get using kvm_read.
+ * Copyright (C) 1999 Kunihiro Ishiguro
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.  
+ */
+
+#include <zebra.h>
+
+#include <kvm.h>
+#include <limits.h>
+#include <fcntl.h>
+
+#include "if.h"
+
+/* get interface MTU to use kvm_read */
+void
+if_kvm_get_mtu (struct interface *ifp)
+{
+  kvm_t *kvmd;
+  struct ifnet ifnet;
+  unsigned long ifnetaddr;
+  int len;
+ 
+  char ifname[IFNAMSIZ];
+  char tname[INTERFACE_NAMSIZ + 1];
+  char buf[_POSIX2_LINE_MAX];
+ 
+  struct nlist nl[] = 
+  {
+    {"_ifnet"},
+    {""}
+  };
+
+  ifp->mtu = -1;
+  
+  kvmd = kvm_openfiles (NULL, NULL, NULL, O_RDONLY, buf);
+
+  if (kvmd == NULL) 
+    return ;
+  
+  kvm_nlist(kvmd, nl);
+ 
+  ifnetaddr = nl[0].n_value;
+ 
+  if (kvm_read(kvmd, ifnetaddr, (char *)&ifnetaddr, sizeof ifnetaddr) < 0) 
+    {
+      kvm_close (kvmd);
+      return ;
+    }
+ 
+  while(ifnetaddr != 0) 
+    {
+      if (kvm_read (kvmd, ifnetaddr, (char *)&ifnet, sizeof ifnet) < 0) 
+	{
+	  kvm_close (kvmd);
+	  return ;
+	}
+
+      if (kvm_read (kvmd, (u_long)ifnet.if_name, ifname, IFNAMSIZ) < 0) 
+	{
+	  kvm_close (kvmd);
+	  return ;
+	}
+
+      len = snprintf (tname, INTERFACE_NAMSIZ + 1, 
+		      "%s%d", ifname, ifnet.if_unit);
+
+      if (strncmp (tname, ifp->name, len) == 0)
+	break;
+
+      ifnetaddr = (u_long)ifnet.if_next;
+    }
+
+  kvm_close (kvmd);
+
+  if (ifnetaddr == 0) 
+    {
+      return ;
+    }
+
+  ifp->mtu = ifnet.if_mtu;
+}