1 files changed, 104 insertions, 0 deletions
diff --git a/src/etc/dhcp/dhclient-exit-hooks.d/01-vyos-cleanup b/src/etc/dhcp/dhclient-exit-hooks.d/01-vyos-cleanup
new file mode 100644
index 000000000..b768e1ae5
--- /dev/null
+++ b/src/etc/dhcp/dhclient-exit-hooks.d/01-vyos-cleanup
@@ -0,0 +1,104 @@
+##
+## VyOS cleanup
+##
+# NOTE: here we use 'ip' wrapper, therefore a route will be actually deleted via /usr/sbin/ip or vtysh, according to the system state
+hostsd_client="/usr/bin/vyos-hostsd-client"
+hostsd_changes=
+
+if [[ $reason =~ (EXPIRE|FAIL|RELEASE|STOP) ]]; then
+    # delete search domains and nameservers via vyos-hostsd
+    logmsg info "Deleting search domains with tag \"dhcp-$interface\" via vyos-hostsd-client"
+    $hostsd_client --delete-search-domains --tag "dhcp-$interface"
+    logmsg info "Deleting nameservers with tag \"dhcp-${interface}\" via vyos-hostsd-client"
+    $hostsd_client --delete-name-servers --tag "dhcp-${interface}"
+    hostsd_changes=y
+
+    # try to delete default ip route 
+    for router in $old_routers; do
+        # check if we are bound to a VRF
+        local vrf_name=$(basename /sys/class/net/${interface}/upper_* | sed -e 's/upper_//')
+        if [ -n $vrf_name ]; then
+            vrf="vrf $vrf_name"
+        fi
+
+        logmsg info "Deleting default route: via $router dev ${interface} ${vrf}"
+        ip -4 route del default via $router dev ${interface} ${vrf}
+    done
+
+    # delete rfc3442 routes
+    if [ -n "$old_rfc3442_classless_static_routes" ]; then
+        set -- $old_rfc3442_classless_static_routes
+        while [ $# -gt 0 ]; do
+            net_length=$1
+            via_arg=''
+            case $net_length in
+                32|31|30|29|28|27|26|25)
+                    if [ $# -lt 9 ]; then
+                        return 1
+                    fi
+                    net_address="${2}.${3}.${4}.${5}"
+                    gateway="${6}.${7}.${8}.${9}"
+                    shift 9
+                    ;;
+                24|23|22|21|20|19|18|17)
+                    if [ $# -lt 8 ]; then
+                        return 1
+                    fi
+                    net_address="${2}.${3}.${4}.0"
+                    gateway="${5}.${6}.${7}.${8}"
+                    shift 8
+                    ;;
+                16|15|14|13|12|11|10|9)
+                    if [ $# -lt 7 ]; then
+                        return 1
+                    fi
+                    net_address="${2}.${3}.0.0"
+                    gateway="${4}.${5}.${6}.${7}"
+                    shift 7
+                    ;;
+                8|7|6|5|4|3|2|1)
+                    if [ $# -lt 6 ]; then
+                        return 1
+                    fi
+                    net_address="${2}.0.0.0"
+                    gateway="${3}.${4}.${5}.${6}"
+                    shift 6
+                    ;;
+                0)  # default route
+                    if [ $# -lt 5 ]; then
+                        return 1
+                    fi
+                    net_address="0.0.0.0"
+                    gateway="${2}.${3}.${4}.${5}"
+                    shift 5
+                    ;;
+                *)  # error
+                    return 1
+                    ;;
+            esac
+            # take care of link-local routes
+            if [ "${gateway}" != '0.0.0.0' ]; then
+                via_arg="via ${gateway}"
+            fi
+            # delete route (ip detects host routes automatically)
+            ip -4 route del "${net_address}/${net_length}" \
+                ${via_arg} dev "${interface}" >/dev/null 2>&1
+        done
+    fi
+fi
+
+if [[ $reason =~ (EXPIRE6|RELEASE6|STOP6) ]]; then
+    # delete search domains and nameservers via vyos-hostsd
+    logmsg info "Deleting search domains with tag \"dhcpv6-$interface\" via vyos-hostsd-client"
+    $hostsd_client --delete-search-domains --tag "dhcpv6-$interface"
+    logmsg info "Deleting nameservers with tag \"dhcpv6-${interface}\" via vyos-hostsd-client"
+    $hostsd_client --delete-name-servers --tag "dhcpv6-${interface}"
+    hostsd_changes=y
+fi
+
+if [ $hostsd_changes ]; then
+    logmsg info "Applying changes via vyos-hostsd-client"
+    $hostsd_client --apply
+else
+    logmsg info "No changes to apply via vyos-hostsd-client"
+fi