1#!/bin/bash
2#
3# Create a "bank" of tap network devices that can be used by the
4# runqemu script. This script needs to be run as root, and will
5# use the tunctl binary from the build system sysroot. Note: many Linux
6# distros these days still use an older version of tunctl which does not
7# support the group permissions option, hence the need to use the build
8# system provided version.
9#
10# Copyright (C) 2010 Intel Corp.
11#
12# SPDX-License-Identifier: GPL-2.0-only
13#
14
15uid=`id -u`
16gid=`id -g`
17if [ -n "$SUDO_UID" ]; then
18    uid=$SUDO_UID
19fi
20if [ -n "$SUDO_GID" ]; then
21    gid=$SUDO_GID
22fi
23
24usage() {
25	echo "Usage: sudo $0 <uid> <gid> <num> <staging_bindir_native>"
26	echo "Where <uid> is the numeric user id the tap devices will be owned by"
27	echo "Where <gid> is the numeric group id the tap devices will be owned by"
28	echo "<num> is the number of tap devices to create (0 to remove all)"
29	echo "<native-sysroot-basedir> is the path to the build system's native sysroot"
30	echo "For example:"
31	echo "$ bitbake qemu-helper-native"
32	echo "$ sudo $0 $uid $gid 4 tmp/sysroots-components/x86_64/qemu-helper-native/usr/bin"
33	echo ""
34	exit 1
35}
36
37if [ $# -ne 4 ]; then
38	echo "Error: Incorrect number of arguments"
39	usage
40fi
41
42TUID=$1
43GID=$2
44COUNT=$3
45STAGING_BINDIR_NATIVE=$4
46
47TUNCTL=$STAGING_BINDIR_NATIVE/tunctl
48if [[ ! -x "$TUNCTL" || -d "$TUNCTL" ]]; then
49	echo "Error: $TUNCTL is not an executable"
50	usage
51fi
52
53if [ $EUID -ne 0 ]; then
54	echo "Error: This script must be run with root privileges"
55	exit
56fi
57
58SCRIPT_DIR=`dirname $0`
59RUNQEMU_IFUP="$SCRIPT_DIR/runqemu-ifup"
60if [ ! -x "$RUNQEMU_IFUP" ]; then
61	echo "Error: Unable to find the runqemu-ifup script in $SCRIPT_DIR"
62	exit 1
63fi
64
65IFCONFIG=`which ip 2> /dev/null`
66if [ -z "$IFCONFIG" ]; then
67	# Is it ever anywhere else?
68	IFCONFIG=/sbin/ip
69fi
70if [ ! -x "$IFCONFIG" ]; then
71       echo "$IFCONFIG cannot be executed"
72       exit 1
73fi
74
75if [ $COUNT -ge 0 ]; then
76	# Ensure we start with a clean slate
77	for tap in `$IFCONFIG link | grep tap | awk '{ print \$2 }' | sed s/://`; do
78		echo "Note: Destroying pre-existing tap interface $tap..."
79		$TUNCTL -d $tap
80	done
81	rm -f /etc/runqemu-nosudo
82else
83	echo "Error: Incorrect count: $COUNT"
84	exit 1
85fi
86
87if [ $COUNT -gt 0 ]; then
88	echo "Creating $COUNT tap devices for UID: $TUID GID: $GID..."
89	for ((index=0; index < $COUNT; index++)); do
90		echo "Creating tap$index"
91		ifup=`$RUNQEMU_IFUP $TUID $GID $STAGING_BINDIR_NATIVE 2>&1`
92		if [ $? -ne 0 ]; then
93			echo "Error running tunctl: $ifup"
94			exit 1
95		fi
96	done
97
98	echo "Note: For systems running NetworkManager, it's recommended"
99	echo "Note: that the tap devices be set as unmanaged in the"
100	echo "Note: NetworkManager.conf file. Add the following lines to"
101	echo "Note: /etc/NetworkManager/NetworkManager.conf"
102	echo "[keyfile]"
103	echo "unmanaged-devices=interface-name:tap*"
104
105	# The runqemu script will check for this file, and if it exists,
106	# will use the existing bank of tap devices without creating
107	# additional ones via sudo.
108	touch /etc/runqemu-nosudo
109fi
110