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authordavidovski <david@davidovski.xyz>2022-03-14 00:14:26 +0000
committerdavidovski <david@davidovski.xyz>2022-03-14 00:14:26 +0000
commitdffbbe56d3f9f17da0244f75b352b87bc0e244df (patch)
treef9472179419c592a4fd42048270da0913f5e6024 /udev/write_net_rules
parentbfdef0f304e13766423aaabd1022c888e3193ff6 (diff)
added udev
Diffstat (limited to 'udev/write_net_rules')
-rwxr-xr-xudev/write_net_rules140
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