meta-google: gbmc-bridge: Rework IP address persistence
This consolidates all of the mechanisms which write out a persistent IP
into a single place. It also transitions to writing a very simple
persistent file instead of systemd style network units.
Change-Id: Ib99d7646178d2c5383cf23b09248bf24544c1d9e
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-lib.sh b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-lib.sh
new file mode 100644
index 0000000..7ccee8e
--- /dev/null
+++ b/meta-google/recipes-google/networking/gbmc-bridge/gbmc-br-lib.sh
@@ -0,0 +1,133 @@
+#!/bin/bash
+# Copyright 2022 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.
+
+[ -n "${gbmc_br_lib_init-}" ] && return
+
+# SC can't find this path during repotest
+# shellcheck disable=SC1091
+source /usr/share/network/lib.sh || exit
+
+# A list of functions which get executed for each configured IP.
+# These are configured by the files included below.
+# Shellcheck does not understand how this gets referenced
+# shellcheck disable=SC2034
+GBMC_BR_LIB_SET_IP_HOOKS=()
+
+gbmc_br_source_dir() {
+ local dir="$1"
+
+ local file
+ while read -r -d $'\0' file; do
+ # SC doesn't like dynamic source loading
+ # shellcheck disable=SC1090
+ source "$file" || return
+ done < <(shopt -s nullglob; for f in "$dir"/*.sh; do printf '%s\0' "$f"; done)
+}
+
+# Load configurations from a known location in the filesystem to populate
+# hooks that are executed after each event.
+gbmc_br_source_dir /usr/share/gbmc-br-lib || exit
+
+gbmc_br_run_hooks() {
+ local -n hookvar="$1"
+ shift
+ local hook
+ for hook in "${hookvar[@]}"; do
+ "$hook" "$@" || return
+ done
+}
+
+gbmc_br_reload() {
+ if [ "$(systemctl is-active systemd-networkd)" != 'inactive' ]; then
+ networkctl reload && networkctl reconfigure gbmcbr
+ fi
+}
+
+gbmc_br_no_ip() {
+ echo "Runtime removing gbmcbr IP" >&2
+ rm -f /run/systemd/network/{00,}-bmc-gbmcbr.network.d/50-public.conf
+ gbmc_br_reload
+}
+
+gbmc_br_reload_ip() {
+ local ip="${1-}"
+
+ if [ -z "$ip" ] && ! ip="$(cat /var/google/gbmc-br-ip 2>/dev/null)"; then
+ echo "Ignoring unconfigured IP" >&2
+ gbmc_br_no_ip
+ return 0
+ fi
+
+ local pfx_bytes=()
+ if ! ip_to_bytes pfx_bytes "$ip"; then
+ echo "Ignoring Invalid IPv6: $ip" >&2
+ gbmc_br_no_ip
+ return 0
+ fi
+
+ local pfx
+ pfx="$(ip_bytes_to_str pfx_bytes)"
+ (( pfx_bytes[9] &= 0xf0 ))
+ local stateless_pfx
+ stateless_pfx="$(ip_bytes_to_str pfx_bytes)"
+ local contents
+ read -r -d '' contents <<EOF
+[Network]
+Address=$pfx/128
+[IPv6Prefix]
+Prefix=$stateless_pfx/80
+PreferredLifetimeSec=60
+ValidLifetimeSec=60
+[IPv6RoutePrefix]
+Route=$pfx/80
+LifetimeSec=60
+[Route]
+Destination=$stateless_pfx/76
+Type=unreachable
+Metric=1024
+EOF
+ echo "Runtime setting gbmcbr IP: $pfx" >&2
+
+ local file
+ for file in /run/systemd/network/{00,}-bmc-gbmcbr.network.d/50-public.conf; do
+ mkdir -p "$(dirname "$file")"
+ printf '%s' "$contents" >"$file"
+ done
+
+ gbmc_br_reload
+}
+
+gbmc_br_set_ip() {
+ local ip="${1-}"
+
+ if [ -n "$ip" ]; then
+ mkdir -p /var/google || return
+ echo "$ip" >/var/google/gbmc-br-ip || return
+ else
+ rm -rf /var/google/gbmc-br-ip
+ fi
+
+ # Remove legacy network configuration
+ rm -rf /etc/systemd/network/{00,}-bmc-gbmcbr.network.d
+
+ gbmc_br_run_hooks GBMC_BR_LIB_SET_IP_HOOKS "$ip" || return
+
+ gbmc_br_reload_ip "$ip"
+}
+
+gbmc_br_lib_init=1
+return 0 2>/dev/null
+echo "gbmc-br-lib is a library, not executed directly" >&2
+exit 1