blob: 93d1a4ad2f7d0796cd249fe26184227500cee4da [file] [log] [blame]
# 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 "${gbmc_ncsi_nft_lib-}" ] || return
gbmc_ncsi_nft_init=
gbmc_ncsi_nft_lastip4=
gbmc_ncsi_nft_lastip6=
gbmc_ncsi_nft_update() {
[ -n "$gbmc_ncsi_nft_init" ] || return
printf 'NCSI firewall for IPv4(%s) IPv6(%s)\n' \
"${gbmc_ncsi_nft_lastip4:-(deleted)}" \
"${gbmc_ncsi_nft_lastip6:-(deleted)}" >&2
local contents=
contents+='table inet filter {'$'\n'
contents+=' chain ncsi_input {'$'\n'
local ip4="$gbmc_ncsi_nft_lastip4"
if [ -n "$ip4" ]; then
contents+=" ip daddr $ip4 goto ncsi_legacy_input"$'\n'
fi
local ip6="$gbmc_ncsi_nft_lastip6"
if [ -n "$ip6" ]; then
contents+=" ip6 daddr $ip6/128 goto ncsi_legacy_input"$'\n'
local ip_bytes=()
ip_to_bytes ip_bytes "$ip6"
# If our address has enough spare bits for appending the BMC suffix
# then we add a rule that allows the BMC subnet. That is, we need a /64
# as input.
local i
for (( i = 8; i < 16; i++ )); do
if (( ip_bytes[$i] != 0 )); then
ip_bytes=()
break
fi
done
if (( ${#ip_bytes[@]} != 0 )); then
ip_bytes[8]=0xfd
local pfx="$(ip_bytes_to_str ip_bytes)"
contents+=" ip6 saddr != $pfx/72 ip6 daddr"
contents+=" $pfx/72 goto ncsi_gbmc_br_pub_input"$'\n'
fi
fi
contents+=' }'$'\n'
contents+=' chain ncsi_forward {'$'\n'
if [ -n "$pfx" ]; then
contents+=" ip6 saddr != $pfx/72 ip6 daddr $pfx/72 accept"$'\n'
fi
contents+=' }'$'\n'
contents+='}'$'\n'
local rfile=/run/nftables/40-gbmc-ncsi-in.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_ncsi_nft_hook() {
if [ "$change" = 'init' ]; then
gbmc_ncsi_nft_init=1
gbmc_ncsi_nft_update
elif [ "$change" = 'addr' -a "$intf" = '@NCSI_IF@' -a "$scope" = 'global' ]; then
if [ "$fam" = 'inet6' ]; then
local -n lastip='gbmc_ncsi_nft_lastip6'
else
local -n lastip='gbmc_ncsi_nft_lastip4'
fi
if [ "$action" = 'add' -a "$ip" != "$lastip" ]; then
lastip="$ip"
gbmc_ncsi_nft_update
fi
if [ "$action" = 'del' -a "$ip" = "$lastip" ]; then
lastip=
gbmc_ncsi_nft_update
fi
fi
}
GBMC_IP_MONITOR_HOOKS+=(gbmc_ncsi_nft_hook)
gbmc_ncsi_nft_lib=1