Add vyod-intfwatchd for restoring IPv6 addresses after link flaps.

As bad as it can be, it seems to sort of work.

1 files changed, 159 insertions, 0 deletions

diff --git a/scripts/vyos-intfwatchd b/scripts/vyos-intfwatchd
new file mode 100644
index 00000000..8f9842c2
--- /dev/null
+++ b/scripts/vyos-intfwatchd
@@ -0,0 +1,159 @@
+#!/usr/bin/perl
+#
+# Module: vyos-restore-static-ipv6.pl
+#
+# **** License ****
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 as
+# published by the Free Software Foundation.
+#
+# This program 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.
+#
+# Copyright (C) 2014 VyOS Development Group
+#
+# **** End License ****
+
+use lib "/opt/vyatta/share/perl5";
+use strict;
+use warnings;
+use POSIX;
+use Fcntl;
+use Sys::Syslog;
+use Vyatta::Config;
+use Vyatta::Interface;
+use Data::Dumper;
+
+use constant
+{
+    # Program settings
+    PROGRAM_NAME => "vyos-intfwatchd",
+    PROGRAM_VERSION => "1.0",
+    PID_FILE => "/var/run/vyos-intfwatchd.pid",
+
+    # Program exit codes
+    SUCCESS => 0,
+    ERROR => 1,
+
+    # Subroutine error codes
+    SUB_ERROR => 0,
+    SUB_SUCCESS => 1,
+
+    # Fcntl file lock/unlock constants
+    SET_EXCLUSIVE_LOCK => 2,
+    UNLOCK => 8
+};
+
+sub daemonize
+{
+     syslog("info", "%s", "Starting in daemon mode");
+
+     my $pid = fork();
+     if (!defined($pid))
+     {
+          # Fork failed
+          die "Could not spawn child process: $!, exiting";
+     }
+     elsif ($pid > 0)
+     {
+         # Child has been spawned succefully,
+         # parent should terminate now
+         exit(SUCCESS);
+     }
+     chdir("/");
+     umask(0);
+     setsid();
+
+     # Close standard i/o stream descriptors
+     open STDIN, "/dev/null" or die "Can't read /dev/null: $!";
+     open STDOUT, ">>/dev/null" or die "Can't write to /dev/null: $!";
+     open STDERR, ">>/dev/null" or die "Can't write to /dev/null: $!";
+}
+
+sub writePid
+{
+    my ($pid, $fh) = @_;
+
+    unless (flock($fh, SET_EXCLUSIVE_LOCK))
+    {
+       syslog("err", "%s", "Could not lock PID file: $!");
+       exit(ERROR);
+    }
+
+    print($fh $pid);
+}
+
+sub releasePid
+{
+    my $fh = shift;
+    flock($fh, UNLOCK);
+    close($fh);
+    unlink(PID_FILE);
+}
+
+
+daemonize();
+my $pidFile = PID_FILE;
+unless (open PID_HANDLE, ">$pidFile")
+{
+    syslog("err", "%s", "Could not create PID file: $!");
+    exit(1);
+}
+writePid($$, \*PID_HANDLE);
+
+my $config = new Vyatta::Config();
+
+my $ip_monitor = "ip monitor link";
+unless (open(HANDLE, "$ip_monitor|"))
+{
+    syslog("err", "%s", qq{Could not start IP monitor: $!\n});
+    exit(1);
+}
+
+sub terminate
+{
+        my $error = shift;
+        syslog("notice", "%s", PROGRAM_NAME." is terminating");
+        releasePid(\*PID_HANDLE);
+        exit(0);
+}
+
+$SIG{'INT'} = \&terminateNormally;
+$SIG{'TERM'} = \&terminateNormally;
+$SIG{'KILL'} = sub { exit(0); };
+
+# This solution should be bad enough to be fixed immediately
+# when feasible.
+
+while(<HANDLE>)
+{
+    if( $_ =~ /^[0-9]+:\s(.*)(@.*)\s<.*UP,.*>/ )
+    {
+        print "Event event $1\n";
+        my $intf_name = $1;
+        my $intf = new Vyatta::Interface($intf_name);
+        my $intf_addr_path = $intf->path() . " address";
+
+        # Get IPv6 addresses
+        my @addresses = grep /:/, $config->returnValues($intf_addr_path);
+        print Dumper(@addresses);
+
+        foreach my $address (@addresses)
+        {
+            system("ip address add $address dev $intf_name");
+            if( $? != 0 )
+            {
+                syslog("err", "%s", "Could not add address $address: $!");
+            }
+            else
+            {
+                syslog("notice", "%s", "Restoring address $address on interface $intf_name");
+            }
+        }
+
+        $intf = undef;
+    }
+}
+