Project.pm: remember users when archiving
[girocco.git] / chrootsetup_linux.sh
blobb888697d4fd8da6676a9248a92c5057915e504fe
1 # chrootsetup_linux.sh
3 # This file SHOULD NOT be executable! It is sourced by jailsetup.sh and
4 # SHOULD NOT be executed directly!
6 # On entry the current directory will be set to the top of the chroot
7 # This script must perform platform-specific chroot setup which includes
8 # creating any dev device entries, setting up proc (if needed), setting
9 # up lib64 (if needed) as well as installing a basic set of whatever libraries
10 # are needed for a chroot to function on this platform.
12 # This script must also define a pull_in_bin function that may be called to
13 # install an executable together with any libraries it depends on into the
14 # chroot.
16 # Finally this script must install a suitable nc.openbsd compatible version of
17 # netcat into the chroot jail that's available as nc.openbsd and which supports
18 # connects to unix sockets.
20 # We are designed to set up the chroot based on binaries from
21 # amd64 Debian lenny; some things may need slight modifications if
22 # being run on a different distribution.
24 chroot_dir="`pwd`"
26 mkdir -p dev proc selinux
27 chown 0:0 proc selinux
28 rm -f lib64
29 ln -s lib lib64
31 # Seed up /dev:
32 rm -f dev/null dev/zero dev/random dev/urandom
33 mknod dev/null c 1 3
34 mknod dev/zero c 1 5
35 mknod dev/random c 1 8
36 mknod dev/urandom c 1 9
37 chmod a+rw dev/null dev/zero dev/random dev/urandom
39 # Extra directories
40 mkdir -p var/run/sshd var/tmp
42 has_files()
44 for _f; do
45 test -f "$_f" || return 1
46 done
47 return 0
50 # Bring in basic libraries:
51 rm -f lib/*
53 # ld.so:
54 [ -d /lib ] && has_files /lib/ld-linux*.so* && cp -p -t lib /lib/ld-linux*.so*
55 [ -d /lib64 ] && has_files /lib64/ld-linux*64.so* && cp -p -t lib /lib64/ld-linux*64.so*
56 has_files lib/ld-linux*.so* || {
57 echo "ERROR: could not find any ld-linux*.so* file" >&2
58 exit 1
61 # Besides '=>' libs, attempt to pick up absolute path libs and create a symlink for upto one level deep
62 extract_libs() {
63 ldd "$1" | grep -v -e linux-gate -e linux-vdso -e ld-linux | awk '{print $1 " " $2 " " $3}' | \
64 while read -r _f1 _f2 _f3; do
65 case "$_f2" in
66 "=>")
67 echo "$_f3"
69 "(0x"*)
70 case "$_f1" in /*.so*)
71 _basedir="$(dirname "$_f1")"
72 _basedir="${_basedir#/}"
73 _basedir="${_basedir#usr/}"
74 case "$_basedir" in
75 lib)
76 echo "$_f1"
78 lib/?*)
79 _basedir="${_basedir#lib/}"
80 case "$_basedir" in */*) :;; *)
81 if [ ! -e "lib/$_basedir" ]; then
82 ln -s . "lib/$_basedir"
84 echo "$_f1"
85 esac
86 esac
87 esac
88 esac
89 done
92 pull_in_lib() {
93 [ -f "$1" ] || return
94 dst="${2%/}/$(basename "$1")"
95 if [ ! -e "$dst" ] || [ "$1" -nt "$dst" ]; then
96 cp -p -t "$2" "$1"
97 for llib in $(extract_libs "$1"); do
98 (pull_in_lib "$llib" lib)
99 done
101 case "$(basename "$1")" in libc.*)
102 # grab libnss_compat.so* from libc location
103 for nlib in "$(dirname "$1")/libnss_compat."so*; do
104 (pull_in_lib "$nlib" "$2")
105 done
106 esac
109 # pull_in_bin takes two arguments:
110 # 1: the full path to a binary to pull in (together with any library dependencies)
111 # 2: the destination directory relative to the current directory to copy it to which
112 # MUST already exist with optional alternate name if the name in the chroot should be different
113 # 3: optional name of binary that if already in $2 and the same as $1 hard link to instead
114 # for example, "pull_in_bin /bin/sh bin" will install the shell into the chroot bin directory
115 # for example, "pull_in_bin /bin/bash bin/sh" will install bash as the chroot bin/sh
116 # IMPORTANT: argument 1 must be a machine binary, NOT a shell script or other interpreted text
117 # IMPORTANT: text scripts can simply be copied in or installed as they don't have libraries to copy
118 # NOTE: it's expected that calling this function on a running chroot may cause temporary disruption
119 # In order to avoid a busy error while replacing binaries we first copy the binary to the
120 # var/tmp directory and then force move it into place after the libs have been brought in.
121 pull_in_bin() {
122 bin="$1"; bdst="$2"
123 if [ -d "${bdst%/}" ]; then
124 bnam="$(basename "$bin")"
125 bdst="${bdst%/}"
126 else
127 bnam="$(basename "$bdst")"
128 bdst="${bdst%/*}"
130 if [ -n "$3" ] && [ "$3" != "$bnam" ] && \
131 [ -r "$bdst/$3" -a -x "$bdst/$3" ] && cmp -s "$bin" "$bdst/$3"; then
132 ln -f "$bdst/$3" "$bdst/$bnam"
133 return 0
135 cp -p -t var/tmp "$bin"
136 # ...and all the dependencies.
137 for lib in $(extract_libs "$bin"); do
138 pull_in_lib "$lib" lib
139 done
140 mv -f "var/tmp/$(basename "$bin")" "$bdst/$bnam"
143 # A catch all that needs to be called after everything's been pulled in
144 chroot_update_permissions() {
145 # Be paranoid
146 [ -n "$chroot_dir" -a "$chroot_dir" != "/" ] || { echo bad '$chroot_dir' >&2; exit 2; }
147 cd "$chroot_dir" || { echo bad '$chroot_dir' >&2; exit 2; }
148 rm -rf var/tmp
149 chown -R 0:0 bin dev lib sbin var
152 # the nc.openbsd compatible utility is available as $var_nc_openbsd_bin
153 pull_in_bin "$var_nc_openbsd_bin" bin/nc.openbsd