meta-google: gbmc-bridge: Recognize public addresses internally
We want to be able to categorize public addresses being used for
internal traffic, and allow them to access internal services.
Change-Id: I1f4b8eaa329954f330c3052c0c789b8e5e3b4662
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/networking/gbmc-bridge.bb b/meta-google/recipes-google/networking/gbmc-bridge.bb
index 80a42bd..6c51a28 100644
--- a/meta-google/recipes-google/networking/gbmc-bridge.bb
+++ b/meta-google/recipes-google/networking/gbmc-bridge.bb
@@ -18,6 +18,7 @@
file://gbmc-br-from-ra.sh \
file://gbmc-br-ensure-ra.sh \
file://gbmc-br-ensure-ra.service \
+ file://gbmc-br-nft.sh \
"
FILES_${PN}_append = " \
@@ -89,6 +90,7 @@
install -d -m0755 "$mondir"
install -m0644 ${WORKDIR}/gbmc-br-ula.sh "$mondir"/
install -m0644 ${WORKDIR}/gbmc-br-from-ra.sh "$mondir"/
+ install -m0644 ${WORKDIR}/gbmc-br-nft.sh "$mondir"/
install -d -m0755 ${D}${libexecdir}
install -m0755 ${WORKDIR}/gbmc-br-ensure-ra.sh ${D}${libexecdir}/
diff --git a/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-nft.sh b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-nft.sh
new file mode 100644
index 0000000..2099185
--- /dev/null
+++ b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-nft.sh
@@ -0,0 +1,63 @@
+# 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 "${gbmc_br_nft_lib-}" ] || return
+
+gbmc_br_nft_init=
+gbmc_br_nft_pfx=
+
+gbmc_br_nft_update() {
+ printf 'gBMC Bridge input firewall for %s\n' \
+ "${gbmc_br_nft_pfx:-(deleted)}" >&2
+
+ local contents=
+ contents+='table inet filter {'$'\n'
+ contents+=' chain gbmc_br_int_input {'$'\n'
+ if [ -n "${gbmc_br_nft_pfx-}" ]; then
+ contents+=" ip6 saddr $gbmc_br_nft_pfx"
+ contents+=" ip6 daddr $gbmc_br_nft_pfx accept"$'\n'
+ fi
+ contents+=' }'$'\n'
+ contents+='}'$'\n'
+
+ local rfile=/run/nftables/40-gbmc-br-int.rules
+ mkdir -p -m 755 "$(dirname "$rfile")"
+ printf '%s' "$contents" >"$rfile"
+
+ echo 'Restarting nftables' >&2
+ systemctl reset-failed nftables
+ systemctl --no-block restart nftables
+}
+
+gbmc_br_nft_hook() {
+ if [ "$change" = 'init' ]; then
+ gbmc_br_nft_init=1
+ gbmc_br_nft_update
+ # Match only global IP addresses on the bridge that match the BMC prefix
+ # (<mpfx>:fdxx:). So 2002:af4:3480:2248:fd02:6345:3069:9186 would become
+ # a 2002:af4:3480:2248:fd00/72 rule.
+ elif [ "$change" = 'addr' -a "$intf" = 'gbmcbr' -a "$scope" = 'global' ] &&
+ [[ "$fam" == 'inet6' && "$ip" =~ ^(([^:]+:){4}fd)[^:]{2}:.*$ ]] &&
+ [[ "$flags" != *tentative* ]]; then
+ pfx="${BASH_REMATCH[1]}00::/72"
+ if [ "$action" = "add" -a "$pfx" != "$gbmc_br_nft_pfx" ]; then
+ gbmc_br_nft_pfx="$pfx"
+ gbmc_br_nft_update
+ fi
+ fi
+}
+
+GBMC_IP_MONITOR_HOOKS+=(gbmc_br_nft_hook)
+
+gbmc_br_nft_lib=1