From 815df2959a76e4a19f5882e40402b9bbca9e70be Mon Sep 17 00:00:00 2001 From: Ghanan Gowripalan Date: Wed, 15 Jan 2020 16:43:36 -0800 Subject: Solicit IPv6 routers when a NIC becomes enabled as a host This change adds support to send NDP Router Solicitation messages when a NIC becomes enabled as a host, as per RFC 4861 section 6.3.7. Note, Router Solicitations will only be sent when the stack has forwarding disabled. Tests: Unittests to make sure that the initial Router Solicitations are sent as configured. The tests also validate the sent Router Solicitations' fields. PiperOrigin-RevId: 289964095 --- pkg/tcpip/header/ndp_router_solicit.go | 36 ++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 pkg/tcpip/header/ndp_router_solicit.go (limited to 'pkg/tcpip/header/ndp_router_solicit.go') diff --git a/pkg/tcpip/header/ndp_router_solicit.go b/pkg/tcpip/header/ndp_router_solicit.go new file mode 100644 index 000000000..9e67ba95d --- /dev/null +++ b/pkg/tcpip/header/ndp_router_solicit.go @@ -0,0 +1,36 @@ +// Copyright 2019 The gVisor Authors. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +package header + +// NDPRouterSolicit is an NDP Router Solicitation message. It will only contain +// the body of an ICMPv6 packet. +// +// See RFC 4861 section 4.1 for more details. +type NDPRouterSolicit []byte + +const ( + // NDPRSMinimumSize is the minimum size of a valid NDP Router + // Solicitation message (body of an ICMPv6 packet). + NDPRSMinimumSize = 4 + + // ndpRSOptionsOffset is the start of the NDP options in an + // NDPRouterSolicit. + ndpRSOptionsOffset = 4 +) + +// Options returns an NDPOptions of the the options body. +func (b NDPRouterSolicit) Options() NDPOptions { + return NDPOptions(b[ndpRSOptionsOffset:]) +} -- cgit v1.2.3