1#!/bin/bash
2# Copyright 2022 Google LLC
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#      http://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15
16[ -n "${gbmc_br_lib_init-}" ] && return
17
18# shellcheck source=meta-google/recipes-google/networking/network-sh/lib.sh
19source /usr/share/network/lib.sh || exit
20# shellcheck source=meta-google/recipes-google/networking/gbmc-net-common/gbmc-net-lib.sh
21source /usr/share/gbmc-net-lib.sh || exit
22
23# A list of functions which get executed for each configured IP.
24# These are configured by the files included below.
25# Shellcheck does not understand how this gets referenced
26# shellcheck disable=SC2034
27GBMC_BR_LIB_SET_IP_HOOKS=()
28
29gbmc_br_source_dir() {
30  local dir="$1"
31
32  local file
33  while read -r -d $'\0' file; do
34    # SC doesn't like dynamic source loading
35    # shellcheck disable=SC1090
36    source "$file" || return
37  done < <(shopt -s nullglob; for f in "$dir"/*.sh; do printf '%s\0' "$f"; done)
38}
39
40# Load configurations from a known location in the filesystem to populate
41# hooks that are executed after each event.
42gbmc_br_source_dir /usr/share/gbmc-br-lib || exit
43
44gbmc_br_run_hooks() {
45  local -n hookvar="$1"
46  shift
47  local hook
48  for hook in "${hookvar[@]}"; do
49    "$hook" "$@" || return
50  done
51}
52
53gbmc_br_no_ip() {
54  echo "Runtime removing gbmcbr IP" >&2
55  rm -f /run/systemd/network/{00,}-bmc-gbmcbr.network.d/50-public.conf
56  gbmc_net_networkd_reload gbmcbr
57}
58
59gbmc_br_reload_ip() {
60  local ip="${1-}"
61
62  if [ -z "$ip" ] && ! ip="$(cat /var/google/gbmc-br-ip 2>/dev/null)"; then
63    echo "Ignoring unconfigured IP" >&2
64    gbmc_br_no_ip
65    return 0
66  fi
67
68  # Remove legacy network configuration
69  rm -rf /etc/systemd/network/{00,}-bmc-gbmcbr.network.d
70
71  local pfx_bytes=()
72  if ! ip_to_bytes pfx_bytes "$ip"; then
73    echo "Ignoring Invalid IPv6: $ip" >&2
74    gbmc_br_no_ip
75    return 0
76  fi
77
78  local pfx
79  pfx="$(ip_bytes_to_str pfx_bytes)"
80  (( pfx_bytes[9] &= 0xf0 ))
81  local stateless_pfx
82  stateless_pfx="$(ip_bytes_to_str pfx_bytes)"
83  local contents
84  read -r -d '' contents <<EOF
85[Network]
86Address=$pfx/128
87[IPv6Prefix]
88Prefix=$stateless_pfx/80
89PreferredLifetimeSec=120
90ValidLifetimeSec=120
91[IPv6RoutePrefix]
92Route=$pfx/80
93LifetimeSec=120
94[Route]
95Destination=$stateless_pfx/76
96Type=unreachable
97Metric=1024
98EOF
99  echo "Runtime setting gbmcbr IP: $pfx" >&2
100
101  local file
102  for file in /run/systemd/network/{00,}-bmc-gbmcbr.network.d/50-public.conf; do
103    mkdir -p "$(dirname "$file")"
104    printf '%s' "$contents" >"$file"
105  done
106
107  gbmc_net_networkd_reload gbmcbr
108}
109
110gbmc_br_set_ip() {
111  local ip="${1-}"
112  local old_ip=
113  if [ -n "$ip" ]; then
114    old_ip="$(cat /var/google/gbmc-br-ip 2>/dev/null)"
115    [ "$old_ip" == "$ip" ] && return
116    mkdir -p /var/google || return
117    echo "$ip" >/var/google/gbmc-br-ip || return
118  else
119    [ ! -f "/var/google/gbmc-br-ip" ] && return
120    rm -rf /var/google/gbmc-br-ip
121  fi
122
123  gbmc_br_run_hooks GBMC_BR_LIB_SET_IP_HOOKS "$ip" || return
124
125  gbmc_br_reload_ip "$ip"
126}
127
128gbmc_br_lib_init=1
129