fix for bug 5892

(cherry picked from commit 5ae305002d35de573a34974104f13ebede556715)

3 files changed, 67 insertions, 21 deletions

diff --git a/scripts/bgp/vyatta-bgp.pl b/scripts/bgp/vyatta-bgp.pl
index 86ec1e14..d97a3e69 100755
--- a/scripts/bgp/vyatta-bgp.pl
+++ b/scripts/bgp/vyatta-bgp.pl
@@ -1138,7 +1138,7 @@ my %qcom = (
 );
 
 my ( $pg, $as, $neighbor );
-my ( $main, $peername, $isneighbor, $checkpeergroups, $checksource, $checklocalas );
+my ( $main, $peername, $isneighbor, $checkpeergroups, $checksource, $isIBGPpeer, $checkforibgpasn);
 
 GetOptions(
     "peergroup=s"             => \$pg,
@@ -1148,16 +1148,19 @@ GetOptions(
     "check-neighbor-ip"       => \$isneighbor,
     "check-peer-groups"       => \$checkpeergroups,
     "check-source=s"	      => \$checksource,
-    "check-local-as"          => \$checklocalas,
+    "is-iBGP"		      => \$isIBGPpeer,
+    "check-for-iBGP-ASN=s"    => \$checkforibgpasn,
     "main"                    => \$main,
 );
 
-main()					if ($main);
-check_peergroup_name($peername)	  	if ($peername);
-check_neighbor_ip($neighbor)            if ($isneighbor);
-check_for_peer_groups( $pg, $as )	if ($checkpeergroups);
-check_source($checksource)	        if ($checksource);
-check_local_as($neighbor, $as)          if ($checklocalas);
+main()					    if ($main);
+check_peergroup_name($peername)	  	    if ($peername);
+check_neighbor_ip($neighbor)                if ($isneighbor);
+check_for_peer_groups( $pg, $as )	    if ($checkpeergroups);
+check_source($checksource)	            if ($checksource);
+check_for_iBGP_ASN($as, $checkforibgpasn)   if ($checkforibgpasn);
+is_IBGP_peer($neighbor, $as)          	    if ($isIBGPpeer);
+
 
 exit 0;
 
@@ -1293,23 +1296,67 @@ sub check_remote_as {
 
 }
 
-# Verify that is local-as is used, the peer isn't in a confedration
-sub check_local_as {
+# check to see if this ASN will make a peer an iBGP peer
+sub check_for_iBGP_ASN {
+    my ($as, $testas) = @_;
+    if ("$as" eq "$testas") { exit 1 ; }
+
+    my $config = new Vyatta::Config;
+    $config->setLevel("protocols bgp $as");
+
+    my @neighbors = $config->listNodes('neighbor');
+    foreach $neighbor (@neighbors) {
+      my $remoteas = $config->returnValue("neighbor $neighbor remote-as");
+      if ("$testas" eq "$remoteas") {
+        exit 1;
+      }
+    }
+    
+    return;
+}
+
+# is this peer an iBGP peer?
+sub is_IBGP_peer {
     my ($neighbor, $as) = @_;
     my $config = new Vyatta::Config;
+    my @ibgp_as;
+    my $neighbor_as;
 
     $config->setLevel("protocols bgp $as");
+
+    # find my local ASN for this neighbor
+    # it's either explicitly defined or in the peer-group
+    if ($config->exists("neighbor $neighbor remote-as")) {
+      $neighbor_as = $config->returnValue("neighbor $neighbor remote-as");
+    }
+    elsif ($config->exists("neighbor $neighbor peer-group")) {
+      my $peergroup = $config->returnValue("neighbor $neighbor peer-group");
+      if ($config->exists("peer-group $peergroup remote-as")) {
+        my $peergroup = $config->returnValue("neighbor $neighbor peer-group");
+        $neighbor_as = $config->returnValue("peer-group $peergroup remote-as");
+      }
+    }
+    else {
+      print "Unable to determine primary ASN for neighbor $neighbor\n";
+      exit 1;
+    }
+
+    # now find my possible local ASNs.  Confederation ASNs are first.
     if ($config->exists('parameters confederation peers')) {
-      my @peers = $config->returnValues('parameters confederation peers');
-      my $remoteas = $config->returnValue("neighbor $neighbor remote-as");
-      foreach my $peeras (@peers) {
-        if ("$peeras" eq "$remoteas") {
-          print "local-as can't be set for neighbors in a peer group\n";
-          return 1;
-        }
+      @ibgp_as = $config->returnValues('parameters confederation peers');
+    }
+    
+    # push router local ASN on the stack
+    push @ibgp_as, $as;
+
+    # and compare neighbor local as to possible local ASNs
+    foreach my $localas (@ibgp_as) {
+      if ("$localas" eq "$neighbor_as") {
+        exit 1;
       }
     }
-    return 0;
+
+    return;
 }
 
 # check that value is either an IPV4 address on system or an interface
diff --git a/templates/protocols/bgp/node.tag/neighbor/node.tag/local-as/node.def b/templates/protocols/bgp/node.tag/neighbor/node.tag/local-as/node.def
index a60b9bb1..42fd3cec 100644
--- a/templates/protocols/bgp/node.tag/neighbor/node.tag/local-as/node.def
+++ b/templates/protocols/bgp/node.tag/neighbor/node.tag/local-as/node.def
@@ -4,6 +4,4 @@ help: Local AS number [REQUIRED]
 val_help: u32:1-4294967294; Local AS number
 syntax:expression: $VAR(@) >=1 && $VAR(@) <= 4294967294; "local-as must be between 1 and 4294967294"
 commit:expression: $VAR(@) != $VAR(../../@); "you can't set local-as the same as the router AS"
-commit:expression: $VAR(../remote-as/@) != $VAR(../../@); "local-as can't be set on iBGP peers"
-commit:expression: exec "/opt/vyatta/sbin/vyatta-bgp.pl --check-local-as --neighbor $VAR(../@) --as $VAR(../../@)"
-
+commit:expression: exec "/opt/vyatta/sbin/vyatta-bgp.pl --is-iBGP --neighbor $VAR(../@) --as $VAR(../../@)"; "local-as can't be set on iBGP peers"
diff --git a/templates/protocols/bgp/node.tag/parameters/confederation/peers/node.def b/templates/protocols/bgp/node.tag/parameters/confederation/peers/node.def
index 71c6b0a8..a5d5b671 100644
--- a/templates/protocols/bgp/node.tag/parameters/confederation/peers/node.def
+++ b/templates/protocols/bgp/node.tag/parameters/confederation/peers/node.def
@@ -3,3 +3,4 @@ type: u32
 help: Peer ASs in the BGP confederation
 val_help: u32:1-4294967294; Peer AS number numbers (ex: "435 234")
 syntax:expression: $VAR(@) >= 1 && $VAR(@) <= 4294967294; "confederation AS id must be between 1 and 4294967294"
+commit:expression: exec "/opt/vyatta/sbin/vyatta-bgp.pl --check-for-iBGP-ASN $VAR(@) --as $VAR(../../../@)"; "can't set confederation ASN to $VAR(@).  Delete neighbors with remote-as $VAR(@) first."