meta-google: gbmc-bridge: Assign stable addresses from RAs
We want BMCs to be able to discover their machine prefix and assign a
stable IPv6 based on that prefix combined with the MAC of the BMC.
Change-Id: I67b8c56f50ff3a970175abcb81b429ceb1258b69
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-from-ra.sh b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-from-ra.sh
new file mode 100644
index 0000000..9a5586b
--- /dev/null
+++ b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-from-ra.sh
@@ -0,0 +1,92 @@
+# Copyright 2021 Google LLC
+#
+# 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.
+
+[ -z "${gbmc_br_from_ra_lib-}" ] || return
+
+source /usr/share/network/lib.sh || exit
+
+gbmc_br_from_ra_init=
+gbmc_br_from_ra_mac=
+declare -A gbmc_br_from_ra_pfxs=()
+declare -A gbmc_br_from_ra_prev_addrs=()
+
+gbmc_br_from_ra_update() {
+ [ -n "$gbmc_br_from_ra_init" -a -n "$gbmc_br_from_ra_mac" ] || return
+
+ local pfx
+ for pfx in "${!gbmc_br_from_ra_pfxs[@]}"; do
+ local cidr
+ if ! cidr="$(ipv6_pfx_to_cidr "$pfx")"; then
+ unset 'gbmc_br_from_ra_pfxs[$pfx]'
+ continue
+ fi
+ if (( cidr == 80 )); then
+ local sfx
+ if ! sfx="$(mac_to_eui48 "$gbmc_br_from_ra_mac")"; then
+ unset 'gbmc_br_from_ra_pfxs[$pfx]'
+ continue
+ fi
+ local addr
+ addr="$(ipv6_pfx_concat "$pfx" "$sfx")"
+ else
+ continue
+ fi
+ local valid="${gbmc_br_from_ra_pfxs["$pfx"]}"
+ if (( valid > 0 )); then
+ if [ -z "${gbmc_br_from_ra_prev_addrs["$addr"]-}" ]; then
+ echo "gBMC Bridge RA Addr Add: $addr" >&2
+ gbmc_br_from_ra_prev_addrs["$addr"]=1
+ fi
+ ip addr replace "$addr" dev gbmcbr noprefixroute
+ else
+ if [ -n "${gbmc_br_from_ra_prev_addrs["$addr"]-}" ]; then
+ echo "gBMC Bridge RA Addr Del: $addr" >&2
+ unset 'gbmc_br_from_ra_prev_addrs[$addr]'
+ fi
+ ip addr del "$addr" dev gbmcbr
+ unset 'gbmc_br_from_ra_pfxs[$pfx]'
+ fi
+ done
+}
+
+gbmc_br_from_ra_hook() {
+ if [ "$change" = 'init' ]; then
+ gbmc_br_from_ra_init=1
+ gbmc_br_from_ra_update
+ elif [[ "$change" == 'route' && "$route" != *' via '* ]] &&
+ [[ "$route" =~ ^(.* dev gbmcbr proto ra .*)( +expires +([^ ]+)sec).*$ ]]; then
+ pfx="${route%% *}"
+ if [ "$action" = 'add' ]; then
+ gbmc_br_from_ra_pfxs["$pfx"]="${BASH_REMATCH[3]}"
+ gbmc_br_from_ra_update
+ elif [ "$action" = 'del' ]; then
+ gbmc_br_from_ra_pfxs["$pfx"]=0
+ gbmc_br_from_ra_update
+ fi
+ elif [ "$change" = 'link' -a "$intf" = 'gbmcbr' ]; then
+ rdisc6 -m gbmcbr -r 1 -w 100 >/dev/null 2>&1
+ if [ "$action" = 'add' -a "$mac" != "$gbmc_br_from_ra_mac" ]; then
+ gbmc_br_from_ra_mac="$mac"
+ gbmc_br_from_ra_update
+ fi
+ if [ "$action" = 'del' -a "$mac" = "$gbmc_br_from_ra_mac" ]; then
+ gbmc_br_from_ra_mac=
+ gbmc_br_from_ra_update
+ fi
+ fi
+}
+
+GBMC_IP_MONITOR_HOOKS+=(gbmc_br_from_ra_hook)
+
+gbmc_br_from_ra_lib=1