blob: 437979241fbf0b920aeb809af12a7508f331b953 [file] [log] [blame]
#!/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=${INTERFACE%%[0-9]*}
match="$match, KERNEL==\"$basename*\""
if [ "$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