diff options
Diffstat (limited to 'udev/write_net_rules')
| -rwxr-xr-x | udev/write_net_rules | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/udev/write_net_rules b/udev/write_net_rules new file mode 100755 index 0000000..f7c7761 --- /dev/null +++ b/udev/write_net_rules @@ -0,0 +1,140 @@ +#!/bin/sh -e + +# This script is run to create persistent network device naming rules +# based on properties of the device. +# If the interface needs to be renamed, INTERFACE_NEW=<name> will be printed +# on stdout to allow udev to IMPORT it. + +# variables used to communicate: +# MATCHADDR MAC address used for the match +# MATCHID bus_id used for the match +# MATCHDEVID dev_id used for the match +# MATCHDRV driver name used for the match +# MATCHIFTYPE interface type match +# COMMENT comment to add to the generated rule +# INTERFACE_NAME requested name supplied by external tool +# INTERFACE_NEW new interface name returned by rule writer + +# Copyright (C) 2006 Marco d'Itri <md@Linux.IT> +# Copyright (C) 2007 Kay Sievers <kay.sievers@vrfy.org> +# +# This program is free software: you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation, either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see <http://www.gnu.org/licenses/>. + +# debug, if UDEV_LOG=<debug> +if [ -n "$UDEV_LOG" ]; then + if [ "$UDEV_LOG" -ge 7 ]; then + set -x + fi +fi + +RULES_FILE='/etc/udev/rules.d/70-persistent-net.rules' + +. /lib/udev/rule_generator.functions + +interface_name_taken() { + local value="$(find_all_rules 'NAME=' $INTERFACE)" + if [ "$value" ]; then + return 0 + else + return 1 + fi +} + +find_next_available() { + raw_find_next_available "$(find_all_rules 'NAME=' "$1")" +} + +write_rule() { + local match="$1" + local name="$2" + local comment="$3" + + { + if [ "$PRINT_HEADER" ]; then + PRINT_HEADER= + echo "# This file was automatically generated by the $0" + echo "# program, run by the persistent-net-generator.rules rules file." + echo "#" + echo "# You can modify it, as long as you keep each rule on a single" + echo "# line, and change only the value of the NAME= key." + fi + + echo "" + [ "$comment" ] && echo "# $comment" + echo "SUBSYSTEM==\"net\", ACTION==\"add\"$match, NAME=\"$name\"" + } >> $RULES_FILE +} + +if [ -z "$INTERFACE" ]; then + echo "missing \$INTERFACE" >&2 + exit 1 +fi + +# Prevent concurrent processes from modifying the file at the same time. +lock_rules_file + +# Check if the rules file is writeable. +choose_rules_file + +# the DRIVERS key is needed to not match bridges and VLAN sub-interfaces +if [ "$MATCHADDR" ]; then + match="$match, DRIVERS==\"?*\", ATTR{address}==\"$MATCHADDR\"" +fi + +if [ "$MATCHDRV" ]; then + match="$match, DRIVERS==\"$MATCHDRV\"" +fi + +if [ "$MATCHDEVID" ]; then + match="$match, ATTR{dev_id}==\"$MATCHDEVID\"" +fi + +if [ "$MATCHID" ]; then + match="$match, KERNELS==\"$MATCHID\"" +fi + +if [ "$MATCHIFTYPE" ]; then + match="$match, ATTR{type}==\"$MATCHIFTYPE\"" +fi + +if [ -z "$match" ]; then + echo "missing valid match" >&2 + unlock_rules_file + exit 1 +fi + +basename=${INTERFACE%%[0-9]*} + +if [ "$INTERFACE_NAME" ]; then + # external tools may request a custom name + COMMENT="$COMMENT (custom name provided by external tool)" + if [ "$INTERFACE_NAME" != "$INTERFACE" ]; then + INTERFACE=$INTERFACE_NAME; + echo "INTERFACE_NEW=$INTERFACE" + fi +else + # if a rule using the current name already exists, find a new name + if interface_name_taken; then + INTERFACE="$basename$(find_next_available "$basename[0-9]*")" + # prevent INTERFACE from being "eth" instead of "eth0" + [ "$INTERFACE" = "${INTERFACE%%[ \[\]0-9]*}" ] && INTERFACE=${INTERFACE}0 + echo "INTERFACE_NEW=$INTERFACE" + fi +fi + +write_rule "$match" "$INTERFACE" "$COMMENT" + +unlock_rules_file + +exit 0 |