[radvd] Build radvd from source; Patch so as not to treat out-of-range MTU as an error

.gitignore

@@ -54,6 +54,9 @@ src/python-click/*
 !src/python-click/Makefile
 src/python3/*
 !src/python3/Makefile
+src/radvd/*
+!src/radvd/Makefile
+!src/radvd/patch/
 src/redis/*
 !src/redis/Makefile
 src/snmpd/*

dockers/docker-router-advertiser/Dockerfile.j2

@@ -9,9 +9,6 @@ ENV DEBIAN_FRONTEND=noninteractive
 # Update apt's cache of available packages
 RUN apt-get update
 
-# Install radvd Debian package
-RUN apt-get -y install radvd
-
 {% if docker_router_advertiser_debs.strip() -%}
 # Copy built Debian packages
 {%- for deb in docker_router_advertiser_debs.split(' ') %}

rules/docker-router-advertiser.mk

@@ -2,7 +2,7 @@
 
 DOCKER_ROUTER_ADVERTISER = docker-router-advertiser.gz
 $(DOCKER_ROUTER_ADVERTISER)_PATH = $(DOCKERS_PATH)/docker-router-advertiser
-$(DOCKER_ROUTER_ADVERTISER)_DEPENDS += $(REDIS_TOOLS)
+$(DOCKER_ROUTER_ADVERTISER)_DEPENDS += $(RADVD) $(REDIS_TOOLS)
 $(DOCKER_ROUTER_ADVERTISER)_LOAD_DOCKERS = $(DOCKER_CONFIG_ENGINE_STRETCH)
 SONIC_DOCKER_IMAGES += $(DOCKER_ROUTER_ADVERTISER)
 SONIC_INSTALL_DOCKER_IMAGES += $(DOCKER_ROUTER_ADVERTISER)

rules/radvd.mk

@@ -0,0 +1,10 @@
+# radvd package
+
+RADVD_VERSION = 2.17-2~bpo9+1
+
+export RADVD_VERSION
+
+RADVD = radvd_$(RADVD_VERSION)_amd64.deb
+$(RADVD)_SRC_PATH = $(SRC_PATH)/radvd
+SONIC_MAKE_DEBS += $(RADVD)
+SONIC_STRETCH_DEBS += $(RADVD)

src/radvd/Makefile

@@ -0,0 +1,31 @@
+.ONESHELL:
+SHELL = /bin/bash
+.SHELLFLAGS += -e
+
+MAIN_TARGET = radvd_$(RADVD_VERSION)_amd64.deb
+
+$(addprefix $(DEST)/, $(MAIN_TARGET)): $(DEST)/% :
+	# Remove any stale files
+	rm -rf ./radvd
+
+	# Clone radvd repo
+	git clone https://salsa.debian.org/debian/radvd.git
+	pushd ./radvd
+
+	# Reset HEAD to the commit of the proper tag
+	# NOTE: Using "git checkout <tag_name>" here detaches our HEAD,
+	# which stg doesn't like, so we use this method instead
+	# NOTE 1: For some reason, tags in the Debian radvd repo are prefixed with "1%"
+	# NOTE 2: "~" in version string is replaced by "_" in branch name
+	git reset --hard debian/1\%$(subst ~,_,$(RADVD_VERSION))
+
+	# Apply patches
+	stg init
+	stg import -s ../patch/series
+
+	# Build source and Debian packages
+	dpkg-buildpackage -rfakeroot -b -us -uc -j$(SONIC_CONFIG_MAKE_JOBS)
+	popd
+
+	# Move the newly-built .deb package to the destination directory
+	mv $* $(DEST)/

src/radvd/patch/0001-Don-t-treat-out-of-range-MTU-as-an-error.patch

@@ -0,0 +1,33 @@
+From 45c15407f11de8b1064b77212727e5234f3ef1e8 Mon Sep 17 00:00:00 2001
+From: Joe LeVeque <jolevequ@microsoft.com>
+Date: Sat, 16 Feb 2019 02:59:10 +0000
+Subject: [PATCH] Don't treat out-of-range MTU as an error
+
+---
+ interface.c | 9 +++++++--
+ 1 file changed, 7 insertions(+), 2 deletions(-)
+
+diff --git a/interface.c b/interface.c
+index 512f2bd..0dc19f4 100644
+--- a/interface.c
++++ b/interface.c
+@@ -200,9 +200,14 @@ int check_iface(struct Interface *iface)
+
+ 	if ((iface->AdvLinkMTU != 0) && ((iface->AdvLinkMTU < MIN_AdvLinkMTU) ||
+ 					 (iface->sllao.if_maxmtu != -1 && (iface->AdvLinkMTU > iface->sllao.if_maxmtu)))) {
+-		flog(LOG_ERR, "AdvLinkMTU for %s (%u) must be zero or between %u and %u", iface->props.name, iface->AdvLinkMTU,
++		// FIXME: Temporary workaround for SONiC. Currently, when interfaces are added
++		// or removed from VLANs, the kernel sets the MTU size for the VLAN to the
++		// default value of 1500. Here, we prevent radvd from treating a larger value
++		// in its configuration as an error. Instead of logging an error and setting
++		// res to -1, we simply log a warning and continue on. Once the aforementioned
++		// behavior is addressed, this patch should be removed.
++		flog(LOG_WARNING, "AdvLinkMTU for %s (%u) must be zero or between %u and %u", iface->props.name, iface->AdvLinkMTU,
+ 		     MIN_AdvLinkMTU, iface->sllao.if_maxmtu);
+-		res = -1;
+ 	}
+
+ 	if (iface->ra_header_info.AdvReachableTime > MAX_AdvReachableTime) {
+-- 
+2.17.1
+

src/radvd/patch/series

@@ -0,0 +1,2 @@
+# This series applies on GIT commit 413616c1b6a05f07f07f3ee6af0cf25a3215fe1a
+0001-Don-t-treat-out-of-range-MTU-as-an-error.patch