3 # Copyright (C) 2006 Marco d'Itri <md@Linux.IT>
4 # Copyright (C) 2007 Kay Sievers <kay.sievers@vrfy.org>
6 # This program is free software; you can redistribute it and/or modify it
7 # under the terms of the GNU General Public License as published by the
8 # Free Software Foundation version 2 of the License.
10 # This script is run to create persistent network device naming rules
11 # based on properties of the device.
12 # If the interface needs to be renamed, INTERFACE_NEW=<name> will be printed
13 # on stdout to allow udev to IMPORT it.
15 # variables used to communicate:
16 # MATCHADDR MAC address used for the match
17 # MATCHID bus_id used for the match
18 # MATCHDRV driver name used for the match
19 # MATCHIFTYPE interface type match
20 # COMMENT comment to add to the generated rule
21 # INTERFACE_NAME requested name supplied by external tool
22 # INTERFACE_NEW new interface name returned by rule writer
24 RULES_FILE='/etc/udev/rules.d/70-persistent-net.rules'
26 . /lib/udev/rule_generator.functions
28 interface_name_taken() {
29 local value="$(find_all_rules 'NAME=' $INTERFACE)"
37 find_next_available() {
38 raw_find_next_available "$(find_all_rules 'NAME=' "$1")"
47 if [ "$PRINT_HEADER" ]; then
49 echo "# This file was automatically generated by the $0"
50 echo "# program run by the persistent-net-generator.rules rules file."
52 echo "# You can modify it, as long as you keep each rule on a single line."
56 [ "$comment" ] && echo "# $comment"
57 echo "SUBSYSTEM==\"net\", ACTION==\"add\"$match, NAME=\"$name\""
61 if [ -z "$INTERFACE" ]; then
62 echo "missing \$INTERFACE" >&2
66 # Prevent concurrent processes from modifying the file at the same time.
69 # Check if the rules file is writeable.
72 # the DRIVERS key is needed to not match bridges and VLAN sub-interfaces
73 if [ "$MATCHADDR" ]; then
74 match="$match, DRIVERS==\"?*\", ATTR{address}==\"$MATCHADDR\""
77 if [ "$MATCHDRV" ]; then
78 match="$match, DRIVERS==\"$MATCHDRV\""
81 if [ "$MATCHID" ]; then
82 match="$match, KERNELS==\"$MATCHID\""
85 if [ "$MATCHIFTYPE" ]; then
86 match="$match, ATTR{type}==\"$MATCHIFTYPE\""
89 if [ -z "$match" ]; then
90 echo "missing valid match" >&2
94 if [ "$INTERFACE_NAME" ]; then
95 # external tools may request a custom name
96 COMMENT="$COMMENT (custom name provided by external tool)"
97 if [ "$INTERFACE_NAME" != "$INTERFACE" ]; then
98 INTERFACE=$INTERFACE_NAME;
99 echo "INTERFACE_NEW=$INTERFACE"
102 # if a rule using the current name already exists, find a new name
103 basename=${INTERFACE%%[0-9]*}
104 if interface_name_taken; then
105 INTERFACE="$basename$(find_next_available "$basename[0-9]*")"
106 echo "INTERFACE_NEW=$INTERFACE"
110 write_rule "$match" "$INTERFACE" "$COMMENT"