Ignore unreachable exclude routes

Otherwise a malformed ip route command is executed.

Signed-off-by: Thomas Bregolin <tbregolin@cloudflare.com>

diff --git a/vpnc-script b/vpnc-script
index 6b5c0d2c3e47308093b06e896fa5a1699e7c9e4d..53ed7308cf332ab7cb08284f3e721617fbc1a661 100755 (executable)
--- a/vpnc-script
+++ b/vpnc-script
@@ -316,7 +316,12 @@ if [ -n "$IPROUTE" ]; then
                NETWORK="$1"
                NETMASK="$2"
                NETMASKLEN="$3"
-               $IPROUTE route add `$IPROUTE route get "$NETWORK" | fix_ip_get_output "/$NETMASKLEN"`
+               ARGS=`$IPROUTE route get "$NETWORK" 2>/dev/null | fix_ip_get_output "/$NETMASKLEN"`
+               if [ -z "$ARGS" ]; then
+                       echo "ignoring non-forwardable exclude route $NETWORK/$NETMASKLEN" >&2
+                       return
+               fi
+               $IPROUTE route add $ARGS
                $IPROUTE route flush cache 2>/dev/null
        }
 
@@ -371,7 +376,12 @@ if [ -n "$IPROUTE" ]; then
                # (keep traffic separate from VPN tunnel)
                NETWORK="$1"
                NETMASKLEN="$2"
-               $IPROUTE -6 route add `$IPROUTE route get "$NETWORK" | fix_ip_get_output "/$NETMASKLEN"`
+               ARGS=`$IPROUTE route get "$NETWORK" 2>/dev/null | fix_ip_get_output "/$NETMASKLEN"`
+               if [ -z "$ARGS" ]; then
+                       echo "ignoring non-forwardable exclude route $NETWORK/$NETMASKLEN" >&2
+                       return
+               fi
+               $IPROUTE -6 route add $ARGS
                $IPROUTE route flush cache 2>/dev/null
        }
 
@@ -457,8 +467,10 @@ else # use route command
                NETWORK="$1"
                NETMASK="$2"
                NETMASKLEN="$3"
+               DEFAULTGW="${DEFAULTGW:-`get_default_gw`}"
                if [ -z "$DEFAULTGW" ]; then
-                       DEFAULTGW="`get_default_gw`"
+                       echo "ignoring non-forwardable exclude route $NETWORK/$NETMASKLEN" >&2
+                       return
                fi
                # Add explicit route to keep traffic for this target separate
                # from tunnel. FIXME: We use default gateway - this is our best
@@ -533,10 +545,15 @@ else # use route command
        set_ipv6_exclude_route() {
                NETWORK="$1"
                NETMASK="$2"
+               IPV6DEFAULTGW="${IPV6DEFAULTGW:-`get_ipv6_default_gw`}"
+               if [ -z "$IPV6DEFAULTGW" ]; then
+                       echo "ignoring non-forwardable exclude route $NETWORK/$NETMASKLEN" >&2
+                       return
+               fi
                # Add explicit route to keep traffic for this target separate
                # from tunnel. FIXME: We use default gateway - this is our best
                # guess in absence of "ip" command to query effective route.
-               route add $route_syntax_inet6_net "$NETWORK/$NETMASK" "`get_ipv6_default_gw`" $route_syntax_interface
+               route add $route_syntax_inet6_net "$NETWORK/$NETMASK" "$IPV6DEFAULTGW" $route_syntax_interface
                :
        }