1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
|
#!/bin/sh
# initrd-do - run a command within an initrd
# Copyright (C) 2008 Loïc Minier <lool@dooz.org>
# Copyright (C) 2011 Linaro Limited
#
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
# SOFTWARE IN THE PUBLIC INTEREST, INC. BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
# DEALINGS IN THE SOFTWARE.
#
# Except as contained in this notice, the name of the author shall not be used
# in advertising or otherwise to promote the sale, use or other dealings in
# this Software without prior written authorization from the author.
#
# depends: sudo
set -e
self="$(basename "$0")"
work_dir=""
new_initrd=""
log() {
echo "$*" >&2
}
log_i() {
log "I:" "$@"
}
log_w() {
log "W:" "$@"
}
die() {
log "E:" "$@"
exit 1
}
usage() {
log "Usage: $self --initrd <initrd-file> [-c <command> [<arg> ...]]"
}
getshell() {
if [ -n "$SHELL" ]; then
echo "$SHELL"
return
fi
PASSWD="$(getent passwd $(id -u) | sed -n 's/.*://p')"
if [ -n "$PASSWD" ]; then
echo "$PASSWD"
return
fi
echo "/bin/sh"
}
escape() {
echo "$*" | sed "s/'/'\"'\"'/g; s/.*/'&'/"
}
# unused; use eval
unescape () {
eval "echo" "$*"
}
cleanup() {
if [ -n "$new_initrd" ]; then
rm -f "$new_initrd"
fi
if [ -n "$work_dir" ]; then
rm -rf "$work_dir"
fi
}
trap "cleanup" 0 1 2 3 9 11 13 15
initrd=""
command="$(escape "$(getshell)")"
while [ $# -gt 0 ]; do
case $1 in
--help)
usage
exit 0
;;
-i|--initrd)
shift
initrd="$1"
if ! shift; then
die "Need an initrd file after --initrd"
fi
;;
-c)
shift
if [ $# -le 0 ]; then
die "Need a command after -c"
fi
command=""
while :; do
command="$command $(escape "$1")"
shift
if [ $# -eq 0 ]; then
break
fi
done
break
;;
*)
# clever handling of args: set initrd first if unset, otherwise set
# command
if [ -z "$initrd" ]; then
initrd="$1"
shift
else
command=""
while :; do
command="$command $(escape "$1")"
shift
if [ $# -eq 0 ]; then
break
fi
done
fi
;;
esac
done
if [ -z "$initrd" ]; then
usage
exit 1
fi
work_dir="$(mktemp -dt "$self.XXXXXXXXXX")"
# subshell to not touch cwd as we will nuke it
( cd "$work_dir"
log_i "Unpacking initrd $initrd"
gunzip -c <"$initrd" | cpio -i --quiet
log_i "Running command:" $command
eval $command
)
err=$?
if [ 0 != $err ]; then
log_w "Command exited with $err; aborting"
exit 1
fi
log_i "Generating new initrd"
new_initrd="$(mktemp -t "$self.XXXXXXXXXX")"
# subshell to not touch cwd as we will nuke it
( cd "$work_dir"
find . | cpio -o -H newc -R 0:0 --quiet | gzip -c >"$new_initrd"
)
log_i "Moving new initrd to $initrd"
mv -f "$new_initrd" "$initrd"
|
