aboutsummaryrefslogtreecommitdiffstats
path: root/iurt_root_command
blob: 9db34047cee1cbb47f58651e4ea13d8b0e58e302 (plain)
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
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
#!/usr/bin/perl
#
# Copyright (C) 2006 Mandriva
# 
# Author: Florent Villard <warly@mandriva.com>
#
# 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, 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, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
# run commands which needs root privilege
#
use lib '/usr/local/lib/perl/iurt/lib';

use strict;
my $program_name = 'iurt_root_command';
use Mkcd::Commandline qw(parseCommandLine usage);
use MDK::Common qw(if_);
use File::NCopy qw(copy);
use Iurt::Util qw(plog_init plog);
use Cwd 'realpath';
use File::Path qw(make_path);

my $arg = @ARGV;
my (@params, %run);
$run{program_name} = $program_name;

my %authorized_modules = ('unionfs' => 1);
my %authorized_rw_bindmounts = ( map { $_ => 1 } qw(/proc /dev/pts /var/cache/icecream) );

$run{todo} = [];
@params = ( 
    #    [ "one letter option", "long name option", "number of args (-X means ´at least X´)", "help text", "function to call", "log info"]
    #
    # no_rsync, config_help and copy_srpm kept for compatibility reasons
    #
    [ "", $program_name, 0, "[--verbose <level>] 
		    [--modprobe <module>] 
		    [--mkdir [--parents] <dir1> <dir2> ... <dirn>]", 
    "$program_name is a perl script to execute commands which need root privilege, it helps probram which needs occasional root privileges for some commands.", 
    sub { $arg or usage($program_name, \@params) }, "Running $program_name" ],

    [ "", "cp", [
    ["", "cp", -1, "[-r] <file1> <file2> ... <filen> <dest>", "copy the files to dest",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting cp command arguments"], 
        ["r", "recursive", 0, "",  
        "Also copy directories and subdirectories",  
        sub { my ($tmp) = @_; $tmp->[0]{recursive} = 1; 1 }, "Set the recursive flag"], 
    ], "[-r] <file1> <file2> ... <filen> <dest>", 
    "Copy files", 
    \&cp, "Copying files" ],

   [ "", "ln", [
   ["", "ln", 2, "<file1> <file2>", "link file1 to file2",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting ln command arguments"], 
    ], "<file1> <file2>", 
    "Link files", 
    \&ln, "Linking files" ],

    [ "", "mkdir", [
    ["", "mkdir", -1, "[--parents] <dir1> <dir2> ... <dirn>", "mkdir create the given path",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting auto mode arguments"], 
        ["p", "parents", 0, "",  
        "Also create needed parents directories",  
        sub { my ($tmp) = @_; $tmp->[0]{parents} = 1; 1 }, "Set the parents flag"], 
    ], "[--parents] <dir1> <dir2> ... <dirn>", 
    "mkdir create the given path", 
    \&mkdir, "Creating the path" ],

    [ "", "rm", [
    ["", "rm", -1, "[-r] <file1> <file2> ... <filen>", "remove the provided files",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting rm command arguments"], 
        ["r", "recursive", 0, "",  
        "Also create needed parents directories",  
        sub { my ($tmp) = @_; $tmp->[0]{recursive} = 1; 1 }, "Set the recursive flag"], 
    ], "[-r] <file1> <file2> ... <filen>", 
    "Remove files", 
    \&rm, "Removing files" ],

    [ "v", "verbose", 1, "<verbose level>", 
    "modprobe try to modprobe the given module if authorized.", 
    sub { $run{verbose} = $_[0]; 1 }, "Setting verbose level" ],
    
    [ "", "modprobe", 1, "<module>", 
    "modprobe try to modprobe the given module if authorized.", 
    \&modprobe, "Modprobing" ],

    [ "", "tar", [
    ["", "tar", 2, "<file> <directory>", "tar directory into file",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting tar command arguments"], 
    ], "<file> <directory>", 
    "Create tarball", 
    \&tar, "Create tarball" ],

    [ "", "untar", [
    ["", "untar", -1, "<file> <directory> [files]", "untar file into directory (optionally selecting files only)",
        sub {    
            my ($tmp, @arg) = @_; 
            $tmp->[0] ||= {}; 
            push @$tmp, @arg; 
            1;
        }, "Setting untar command arguments"], 
    ], "<file> <directory> [files]", 
    "Uncompress tarball", 
    \&untar, "Uncompress tarball" ],

    [ "", "bindmount", 2, "<source> <dest>", 
    "bind mount source on dest", 
    \&bindmount, "Bind mounting" ],

    [ "", "umount", 1, "<directory>", 
    "umount the given directory", 
    \&umount, "Unmounting" ],

    [ "", "useradd", 3, "<directory> <username> [uid]", 
    "Add user in given chroot", 
    \&useradd, "Useradd" ],

    [ "", "urpmi", [
    ["", "urpmi", -1, "urpmi options", "run urpmi with urpmi options (should have chroot options)",
        sub {    
            my ($tmp, @arg) = @_; 
            push @$tmp, @arg; 
            1;
        }, "Setting urpmi options"], 
    ], "urpmi options", 
    "Run urpmi in chroot", 
    \&urpmi, "Run urpmi in chroot" ],
);

my %commands_with_more_args = (
    "--urpmi" => [ \&urpmi, "urpmi" ],
    "--urpmi-addmedia" => [ \&urpmi_addmedia, "urpmi.addmedia" ],
    "--chroot" => [ \&run_chroot, "chroot" ],
);

open(my $LOG, ">&STDERR");
$run{LOG} = sub { print $LOG @_ };

plog_init($program_name, $LOG, $run{verbose});
#plog_init($program_name, $LOG, 7, 1);

my $todo;

# (blino) do not use mkcd to parse complicated command lines with unhandled options
# I fail to make mkcd not parse arguments after -- on command line
if (my $command = $commands_with_more_args{$ARGV[0]}) {
    my (undef, @options) = @ARGV;
    $todo = [ [ $command->[0], \@options, $command->[1] ] ];
} else {
    $todo = parseCommandLine($program_name, \@ARGV, \@params);
    @ARGV and usage($program_name, \@params, "@ARGV, too many arguments");
}

my $ok = 1;
foreach my $t (@$todo)  {
    plog('DEBUG', $t->[2]);
    my $ok2 = &{$t->[0]}(\%run, @{$t->[1]});
    $ok2 or plog("ERROR: $t->[2]");
    $ok &&= $ok2;
}
plog('DEBUG', "Success!") if $ok;
exit !$ok;

sub modprobe {
    my ($_run, $module) = @_;
    if (!$authorized_modules{$module}) {
	plog("ERROR: unauthorized module $module");
	return 0;
    }
    open my $modules, '/proc/modules';
    while (my $m = <$modules>) {
	if ($m =~ /unionfs/) {
	    return 1;
	}
    }
    system("/sbin/depmod", "-a");
    !system("/sbin/modprobe", "-f", $module);
}

sub mkdir {
    my ($_run, $opt, @dir) = @_;
    foreach my $path (@dir) {
	-d $path and next;
	if ($path =~ m,/dev|/proc|/root|/var, && $path !~ /chroot|unionfs/) {
	    plog('FAIL', "ERROR: $path creation forbidden");
	}
	if ($opt->{parents}) {
	    make_path($path);
	} else {
	    mkdir $path;
	}
    }
    1;
}

sub rm {
    my ($_run, $opt, @files) = @_;
    my $ok = 1;
    my $done;
    my $unauthorized = "^(/etc|/root|/dev|/var|/lib|/usr)";

    foreach my $f (@files) {
	if (-d $f) {
	    if (!$opt->{recursive}) {
		plog('WARN', "can't remove directories without the -r option");
		$ok = 0;
	    } else {
		if ($f =~ m,$unauthorized,) {
		    plog('FAIL', "removal of $f forbidden");
		    $ok = 0;
		} else {
		    system('rm', '-rf', $f);
		    plog('DEBUG', "removing $f");
		    $done = 1;
		}
	    }
	} else {
	    if ($f =~ m,/$unauthorized,) {
		plog("removal of $f forbidden");
		$ok = 0;
	    } else {
		# CM: The original regexp was /\*?/, which doesn't seem to be
		#     what we want. Check if we can always glob instead of
		#     testing, or if glob expansion is needed at all

		if ($f =~ /[*?]/) {
		    foreach my $file (glob $f) {
			if ($f =~ m,$unauthorized,) {
			    plog('FAIL', "removal of $f forbidden");
			    $ok = 0;
			} else {
			    unlink $file;
			    $done = 1;
			    plog('DEBUG', "removing $file");
			}
		    }
		} else {
		    unlink $f;
		    $done = 1;
		    plog('DEBUG', "removing $f");
		}
	    }
	}
    }
    if (!$done) { plog('DEBUG', "nothing deleted") }
    $ok;
}

sub cp {
    my ($_run, $opt, @files) = @_;
    my $ok = 1;
    my $done;
    my $dest = pop @files;
    my $unauthorized = "^(/etc|/root|/dev|/var|/lib|/usr)";
    if ($dest =~ /$unauthorized/ || $dest eq '/') {
	plog('FAIL', "copying to $dest forbidden");
	return;
    }	
    foreach my $f (@files) {
	if (-d $f) {
	    if (!$opt->{recursive}) {
		plog('WARN', "can't copy directories without the -r option");
		$ok = 0;
	    } else {
		system('cp', '-raf', $f);
		plog('DEBUG', "copying $f -> $dest");
		$done = 1;
	    }
	} else {
	    if ($f =~ /\*?/) {
		foreach my $file (glob $f) {
		    if (copy $file, $dest) {
			$done = 1;
			plog('DEBUG', "copying $file -> $dest");
		    } else {
			$ok = 0;
			plog('FAIL', "copying $file to $dest failed ($!)");
		    }
		}
	    } else {
		if (copy $f, $dest) {
		    $done = 1;
		    plog('DEBUG', "copying $f -> $dest");
		} else {
		    $ok = 0;
		    plog('FAIL', "copying $f to $dest failed ($!)");
		}
	    }
	}
    }
    if (!$done) { plog('DEBUG', "nothing copied") }
    $ok;
}

sub ln {
    my ($_run, $_opt, $file1, $file2) = @_;
    my $unauthorized = "^(/etc|/root|/dev|/var|/lib|/usr)";
    if ($file2 =~ /$unauthorized/ || $file2 eq '/') {
	plog('FAIL', "linking to $file2 forbidden");
	return;
    }	
    link $file1, $file2;
}

sub check_path_authorized {
    my ($path) = @_;
    if (!$ENV{SUDO_USER}) {
	plog('FAIL', "must be run from sudo");
	return;
    }
    my $authorized = (getpwnam($ENV{SUDO_USER}))[7];
    if (!$authorized) {
	plog('FAIL', "can't find home for $ENV{SUDO_USER}");
	return;
    }

    #- check authorization for canonicalized path (with .. and symlinks resolved)
    my $realpath = realpath($path);
    if ($realpath !~ /^\Q$authorized\E/) {
	plog('FAIL', "$path forbidden");
	return;
    }

    1;
}

sub tar {
    my ($_run, $_opt, $file, $dir) = @_;
    if (!$file || !$dir) {
	plog('FAIL', "tar: missing arguments");
	return;	
    }
    check_path_authorized($file) && check_path_authorized($dir) or return;
    return !system('tar', 'caf', $file, '-C', $dir, '.');
}

sub untar {
    my ($_run, $_opt, $file, $dir, @o_files) = @_;
    if (!$file || !$dir) {
	plog('FAIL', "untar: missing arguments");
	return;	
    }
    check_path_authorized($file) && check_path_authorized($dir) or return;
    if (grep { /^-/ } @o_files) {
	plog('FAIL', "untar: options forbidden");
	return;	
    }
    make_path($dir);
    return !system('tar', 'xf', $file, '-C', $dir, @o_files);
}

sub bindmount {
    my ($_run, $source, $dest) = @_;
    check_path_authorized($dest) or return;
    system("mount", "--bind", $source, $dest) == 0 or return;
    if (!$authorized_rw_bindmounts{$source}) {
        system("mount", "-o", "remount,ro", $dest) == 0 or return;
    }
    return 1;
}

sub umount {
    my ($_run, $dir) = @_;
    check_path_authorized($dir) or return;
    return !system("umount", $dir);
}

sub useradd {
    my ($_run, $dir, $username, $o_uid) = @_;
    check_path_authorized($dir) or return;
    return system('chroot', $dir, 'useradd', if_($o_uid, '-o', '--uid', $o_uid), $username) == 0
      || system('chroot', $dir, 'id', $username) == 0;
}

sub check_urpmi_chroot_options {
    my ($options) = @_;

    # get all --something options
    my %optvals;
    my $current_opt;
    foreach (@$options) {
        if (/^--/) {
            $current_opt = $_;
        } else {
            if ($current_opt) {
                $optvals{$current_opt} = $_;
            }
            undef $current_opt;
        }
    }

    # check that urpmi is rooted and using allowed chroot paths
    my $is_rooted = 0;
    foreach (qw(--root --urpmi-root)) {
        if ($optvals{$_}) {
            check_path_authorized($optvals{$_}) or return;
            $is_rooted = 1;
        }
    }
    if (!$is_rooted) {
	plog('FAIL', "urpmi commands must be rooted");
	return;	
    }

    return 1;
}

sub urpmi {
    my ($_run, @options) = @_;
    return check_urpmi_chroot_options(\@options) && !system('urpmi', @options);
}

sub urpmi_addmedia {
	my ($_run, @options) = @_;
	return check_urpmi_chroot_options(\@options) && !system('urpmi.addmedia', @options);
}

sub run_chroot {
    my ($_run, $dir, @options) = @_;
    if (!$dir) {
	plog('FAIL', "chroot: need directory argument");
	return;	
    }
    check_path_authorized($dir) or return;

    return !system("chroot", $dir, @options);
}