1 files changed, 81 insertions, 0 deletions
diff --git a/zebra/if_linkdetect.c b/zebra/if_linkdetect.c
new file mode 100644
index 00000000..9ae7c6a6
--- /dev/null
+++ b/zebra/if_linkdetect.c
@@ -0,0 +1,81 @@
+/* Interface link state tracking
+ * Copyright (C) 2008 Stephen Hemminger
+ *
+ * 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 "log.h"
+#include "privs.h"
+
+#include "log.h"
+#include "privs.h"
+#include "prefix.h"
+
+#include "zebra/interface.h"
+
+extern struct zebra_privs_t zserv_privs;
+
+static int
+linkdetect (const char *name, int onoff)
+{
+  FILE *fp;
+  int save_errno;
+  char proc_name[128];
+
+  snprintf(proc_name, sizeof(proc_name)-1, 
+	   "/proc/sys/net/ipv4/conf/%s/link_detect", name);
+  
+  if ( zserv_privs.change(ZPRIVS_RAISE) )
+    zlog_err ("Can't raise privileges, %s", safe_strerror (errno) );
+
+  fp = fopen (proc_name, "w");
+  save_errno = errno;
+  if (!fp)
+    {
+      if ( zserv_privs.change(ZPRIVS_LOWER) )
+	zlog_err ("Can't lower privileges, %s", safe_strerror (errno));
+
+      zlog_info("Can't %s link-detect, %s:%s",
+		onoff ? "enable" : "disable",
+		proc_name, safe_strerror(save_errno));
+      return -1;
+    }
+  else
+    {
+      fprintf (fp, "%d\n", onoff);
+      fclose (fp);
+
+      if ( zserv_privs.change(ZPRIVS_LOWER) )
+	zlog_err ("Can't lower privileges, %s", safe_strerror (errno));
+
+      return onoff;
+    }
+}
+
+int
+if_linkdetect_on (const char *name)
+{
+  return linkdetect (name, 1);
+}
+
+int
+if_linkdetect_off (const char *name)
+{
+  return linkdetect (name, 1);
+}