aboutsummaryrefslogtreecommitdiffstats
path: root/share/libmsec.py
blob: eac4831069ea4f8b290f7877acd155c6ef4eb7e8 (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
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
#---------------------------------------------------------------
# Project         : Mandrake Linux
# Module          : share
# File            : libmsec.py
# Version         : $Id$
# Author          : Frederic Lepied
# Created On      : Mon Dec 10 22:52:17 2001
# Purpose         : all access points of the msec utility.
#---------------------------------------------------------------

import ConfigFile
import Config
from Log import *

import os
import grp
import Perms
import gettext
import pwd
import re
import string
import commands

try:
    cat = gettext.Catalog('msec')
    _ = cat.gettext
except IOError:
    _ = str

SUFFIX='.msec'
_interactive=0
_same_level=1

# list of config files

ATALLOW = '/etc/at.allow'
AUTOLOGIN = '/etc/sysconfig/autologin'
BASTILLENOLOGIN = '/etc/bastille-no-login'
CRON = '/etc/cron.d/msec'
CRONALLOW = '/etc/cron.allow'
GDM = '/etc/pam.d/gdm'
GDMCONF = '/etc/X11/gdm/gdm.conf'
HALT = '/etc/security/console.apps/halt'
HOSTCONF = '/etc/host.conf'
HOSTSDENY = '/etc/hosts.deny'
INITTAB = '/etc/inittab'
ISSUE = '/etc/issue'
ISSUENET = '/etc/issue.net'
KDE = '/etc/pam.d/kde'
KDMRC = '/usr/share/config/kdm/kdmrc'
LDSOPRELOAD = '/etc/ld.so.preload'
LILOCONF = '/etc/lilo.conf'
LOGINDEFS = '/etc/login.defs'
MENULST = '/boot/grub/menu.lst'
MSEC = '/etc/sysconfig/msec'
MSECBIN = '/usr/sbin/msec'
MSECCRON = '/etc/cron.hourly/msec'
MSEC_XINIT = '/etc/X11/xinit.d/msec'
PASSWD = '/etc/pam.d/passwd'
POWEROFF = '/etc/security/console.apps/poweroff'
REBOOT = '/etc/security/console.apps/reboot'
SECURETTY = '/etc/securetty'
SECURITYCONF = '/var/lib/msec/security.conf'
SECURITYCRON = '/etc/cron.daily/msec'
SECURITYSH = '/usr/share/msec/security.sh'
SERVER = '/etc/security/msec/server'
SHADOW = '/etc/shadow'
SHUTDOWN = '/etc/security/console.apps/shutdown'
SHUTDOWNALLOW = '/etc/shutdown.allow'
SSHDCONFIG = '/etc/ssh/sshd_config'
STARTX = '/usr/X11R6/bin/startx '
SU = '/etc/pam.d/su'
SYSCTLCONF = '/etc/sysctl.conf'
SYSLOGCONF = '/etc/syslog.conf'
SYSTEM_AUTH = '/etc/pam.d/system-auth'
XDM = '/etc/pam.d/xdm'
XSERVERS = '/etc/X11/xdm/Xservers'

# constants to keep in sync with shadow.py
NONE=0
ALL=1
LOCAL=2

# config files => actions

ConfigFile.add_config_assoc(INITTAB, '/sbin/telinit q')
ConfigFile.add_config_assoc('/etc(?:/rc.d)?/init.d/(.+)', '[ -f /var/lock/subsys/@1 ] && @0 reload')
ConfigFile.add_config_assoc(SYSCTLCONF, '/sbin/sysctl -e -p /etc/sysctl.conf')
ConfigFile.add_config_assoc(SSHDCONFIG, '[ -f /var/lock/subsys/sshd ] && /etc/rc.d/init.d/sshd restart')
ConfigFile.add_config_assoc(LILOCONF, '[ `/usr/sbin/detectloader` = LILO ] && /sbin/lilo')
ConfigFile.add_config_assoc(SYSLOGCONF, '[ -f /var/lock/subsys/syslog ] && service syslog reload')
ConfigFile.add_config_assoc('^/etc/issue$', '/usr/bin/killall mingetty')

#

def changing_level():
    'D'
    global _same_level
    _same_level=0
    
# configuration rules

def set_secure_level(level):
    msec = ConfigFile.get_config_file(MSEC)

    val = msec.get_shell_variable('SECURE_LEVEL')

    if not val or int(val) != level:
        _interactive and log(_('Setting secure level to %s') % level)
        msec.set_shell_variable('SECURE_LEVEL', level)

def get_secure_level():
    'D'
    msec = ConfigFile.get_config_file(MSEC)
    return msec.get_shell_variable('SECURE_LEVEL')

def set_server_level(level):
    _interactive and log(_('Setting server level to %s') % level)
    securityconf = ConfigFile.get_config_file(SECURITYCONF)
    securityconf.set_shell_variable('SERVER_LEVEL', level)

def get_server_level():
    'D'
    securityconf = ConfigFile.get_config_file(SECURITYCONF)
    level = securityconf.get_shell_variable('SERVER_LEVEL')
    if level: return level
    msec = ConfigFile.get_config_file(MSEC)
    return msec.get_shell_variable('SECURE_LEVEL')

def create_server_link():
    '''  If SERVER_LEVEL (or SECURE_LEVEL if absent) is greater than 3
in /etc/security/msec/security.conf, creates the symlink /etc/security/msec/server
to point to /etc/security/msec/server.<SERVER_LEVEL>. The /etc/security/msec/server
is used by chkconfig --add to decide to add a service if it is present in the file
during the installation of packages.'''
    level = get_server_level()
    server = ConfigFile.get_config_file(SERVER)
    if level in ('0', '1', '2', '3'):
        _interactive and log(_('Allowing chkconfig --add from rpm'))
        server.exists() and server.unlink()
    else:
        _interactive and log(_('Restricting chkconfig --add from rpm'))
        server.symlink(SERVER + '.' + str(level))

# helper function for set_root_umask and set_user_umask
def set_umask(variable, umask, msg):
    'D'
    msec = ConfigFile.get_config_file(MSEC)
    
    if msec.exists():
        val = msec.get_shell_variable(variable)
    else:
        val = None

    # don't lower security when not changing security level
    if _same_level:
        if val:
            octal = int(umask, 8) | int(val, 8)
            umask = '0%o' % octal
                
    if val != umask:
        _interactive and log(_('Setting %s umask to %s') % (msg, umask))
        msec.set_shell_variable(variable, umask)
    
def set_root_umask(umask):
    '''  Set the root umask.'''
    set_umask('UMASK_ROOT', umask, 'root')

def set_user_umask(umask):
    '''  Set the user umask.'''
    set_umask('UMASK_USER', umask, 'users')

# the listen_tcp argument is kept for backward compatibility
def allow_x_connections(arg, listen_tcp=None):
    '''  Allow/Forbid X connections. First arg specifies what is done
on the client side: ALL (all connections are allowed), LOCAL (only
local connection) and NONE (no connection).'''
    
    msec = ConfigFile.get_config_file(MSEC_XINIT)

    val = msec.exists() and msec.get_match('/usr/X11R6/bin/xhost\s*\+\s*([^#]*)')

    if val:
        if val == '':
            val = ALL
        elif val == 'localhost':
            val = LOCAL
        else:
            val = NONE
    else:
        val = NONE
        
    # don't lower security when not changing security level
    if _same_level:
        if val == NONE or (val == LOCAL and arg == ALL):
            return
        
    if arg == ALL:
        if val != arg:
            _interactive and log(_('Allowing users to connect X server from everywhere'))
            msec.exists() and msec.replace_line_matching('/usr/X11R6/bin/xhost', '/usr/X11R6/bin/xhost +', 1)

    elif arg == LOCAL:
        if val != arg:
            _interactive and log(_('Allowing users to connect X server from localhost'))
            msec.exists() and msec.replace_line_matching('/usr/X11R6/bin/xhost', '/usr/X11R6/bin/xhost + localhost', 1)
        
    elif arg == NONE:
        if val != arg:
            _interactive and log(_('Restricting X server connection to the console user'))
            msec.exists() and msec.remove_line_matching('/usr/X11R6/bin/xhost', 1)
        
    else:
        error(_('invalid allow_x_connections arg: %s') % arg)
        return

STARTX_REGEXP = '(\s*clientargs=".*) -nolisten tcp(.*")'
XSERVERS_REGEXP = '(\s*[^#]+/usr/X11R6/bin/X .*) -nolisten tcp(.*)'
GDMCONF_REGEXP = '(\s*command=.*/X.*?) -nolisten tcp(.*)$'
def allow_xserver_to_listen(arg):
    ''' The argument specifies if clients are authorized to connect
to the X server on the tcp port 6000 or not.'''
    
    startx = ConfigFile.get_config_file(STARTX)
    xservers = ConfigFile.get_config_file(XSERVERS)
    gdmconf = ConfigFile.get_config_file(GDMCONF)

    val_startx = startx.exists() and startx.get_match(STARTX_REGEXP)
    val_xservers = xservers.exists() and xservers.get_match(XSERVERS_REGEXP)
    val_gdmconf = gdmconf.exists() and gdmconf.get_match(GDMCONF_REGEXP)
    
    # don't lower security when not changing security level
    if _same_level:
        if val_startx and val_xservers and val_gdmconf:
            return
        
    if arg:
        if val_startx or val_xservers or val_gdmconf:
            _interactive and log(_('Allowing the X server to listen to tcp connections'))
            if not (_same_level and val_startx):
                startx.exists() and startx.replace_line_matching(STARTX_REGEXP, '@1@2')
            if not (_same_level and val_xservers):
                xservers.exists() and xservers.replace_line_matching(XSERVERS_REGEXP, '@1@2', 0, 1)
            if not (_same_level and val_gdmconf):
                gdmconf.exists() and gdmconf. replace_line_matching(GDMCONF_REGEXP, '@1@2', 0, 1)
    else:
        if not val_startx or not val_xservers or not val_gdmconf:
            _interactive and log(_('Forbidding the X server to listen to tcp connection'))
            startx.exists() and startx.replace_line_matching('clientargs="(.*?)( -nolisten tcp)?"', 'clientargs="@1 -nolisten tcp"')
            xservers.exists() and xservers.replace_line_matching('(\s*[^#]+/usr/X11R6/bin/X .*?)( -nolisten tcp)?$', '@1 -nolisten tcp', 0, 1)
            gdmconf.exists() and gdmconf. replace_line_matching('(\s*command=.*/X.*?)( -nolisten tcp)?$', '@1 -nolisten tcp', 0, 1)

def set_shell_timeout(val):
    '''  Set the shell timeout. A value of zero means no timeout.'''

    msec = ConfigFile.get_config_file(MSEC)

    if msec.exists():
        old = msec.get_shell_variable('TMOUT')
        if old != None:
            old = int(old)
    else:
        old = None
        
    # don't lower security when not changing security level
    if _same_level:
        if old != None and old > val:
            return

    if old != val:
        _interactive and log(_('Setting shell timeout to %s') % val)
        msec.set_shell_variable('TMOUT', val)

def set_shell_history_size(size):
    '''  Set shell commands history size. A value of -1 means unlimited.'''
    msec = ConfigFile.get_config_file(MSEC)

    if msec.exists():
        val = msec.get_shell_variable('HISTFILESIZE')
    else:
        val = None
        
    # don't lower security when not changing security level
    if _same_level:
        if val != None:
            val = int(val)
            if size == -1 or val < size:
                return
            
    if size >= 0:
        if val != size:
            _interactive and log(_('Setting shell history size to %s') % size)
            msec.set_shell_variable('HISTFILESIZE', size)
    else:
        if val != None:
            _interactive and log(_('Removing limit on shell history size'))
            msec.remove_line_matching('^HISTFILESIZE=')
        
def allow_reboot(arg):
    '''  Allow/Forbid reboot by the console user.'''
    shutdownallow = ConfigFile.get_config_file(SHUTDOWNALLOW)
    sysctlconf = ConfigFile.get_config_file(SYSCTLCONF)
    kdmrc = ConfigFile.get_config_file(KDMRC)
    gdmconf = ConfigFile.get_config_file(GDMCONF)
    
    val_shutdownallow = shutdownallow.exists()
    val_sysctlconf = sysctlconf.exists() and sysctlconf.get_shell_variable('kernel.sysrq')
    num = 0
    val = {}
    for f in [SHUTDOWN, POWEROFF, REBOOT, HALT]:
        val[f] = ConfigFile.get_config_file(f).exists()
        if val[f]:
            num = num + 1
    val_kdmrc = kdmrc.exists() and kdmrc.get_shell_variable('AllowShutdown')
    val_gdmconf = gdmconf.exists() and gdmconf.get_shell_variable('SystemMenu')

    # don't lower security when not changing security level
    if _same_level:
        if val_shutdownallow and val_sysctlconf == '0' and num == 0 and val_kdmrc == 'None' and val_gdmconf == 'false':
            return
        
    if arg:
        _interactive and log(_('Allowing reboot to the console user'))
        if not (_same_level and val_shutdownallow):
            shutdownallow.exists() and shutdownallow.move(SUFFIX)
        for f in [SHUTDOWN, POWEROFF, REBOOT, HALT]:
            cfg = ConfigFile.get_config_file(f)
            if not (_same_level and not val[f]):
                cfg.exists() or cfg.touch()
        if not (_same_level and val_sysctlconf == '0'):
            sysctlconf.set_shell_variable('kernel.sysrq', 1)
        if not (_same_level and val_kdmrc == 'None'):
            kdmrc.exists() and kdmrc.set_shell_variable('AllowShutdown', 'All', 'X-:\*-Greeter', '^\s*$')
        if not (_same_level and val_gdmconf == 'false'):
            gdmconf.exists() and gdmconf.set_shell_variable('SystemMenu', 'true', '\[greeter\]', '^\s*$')
    else:
        _interactive and log(_('Forbidding reboot to the console user'))
        ConfigFile.get_config_file(SHUTDOWNALLOW, SUFFIX).touch()
        for f in [SHUTDOWN, POWEROFF, REBOOT, HALT]:
            ConfigFile.get_config_file(f).unlink()
        sysctlconf.set_shell_variable('kernel.sysrq', 0)
        kdmrc.exists() and kdmrc.set_shell_variable('AllowShutdown', 'None', 'X-:\*-Greeter', '^\s*$')
        gdmconf.exists() and gdmconf.set_shell_variable('SystemMenu', 'false', '\[greeter\]', '^\s*$')
    
def allow_user_list(arg):
    '''  Allow/Forbid the list of users on the system on display managers (kdm and gdm).'''
    kdmrc = ConfigFile.get_config_file(KDMRC)
    gdmconf = ConfigFile.get_config_file(GDMCONF)
    
    oldval_kdmrc = kdmrc.exists() and kdmrc.get_shell_variable('ShowUsers')
    oldval_gdmconf = gdmconf.exists() and gdmconf.get_shell_variable('Browser')
    
    if arg:
        msg = 'Allowing the listing of users in display managers'
        val_kdmrc = 'All'
        val_gdmconf = 'true'
    else:
        msg = 'Disabling the listing of users in display managers'
        val_kdmrc = 'None'
        val_gdmconf = 'false'

    # don't lower security when not changing security level
    if _same_level:
        if oldval_kdmrc == 'None' and oldval_gdmconf == 'false':
            return
        if oldval_kdmrc == 'None':
            val_kdmrc = 'None'
        if oldval_gdmconf == 'false':
            val_gdmconf = 'false'
    
    if (gdmconf.exists() and oldval_gdmconf != val_gdmconf) or (kdmrc.exists() and oldval_kdmrc != val_kdmrc):
        _interactive and log(_(msg))
        oldval_kdmrc != val_gdmconf and kdmrc.exists() and kdmrc.set_shell_variable('ShowUsers', val_kdmrc)
        oldval_gdmconf != val_gdmconf and gdmconf.exists() and gdmconf.set_shell_variable('Browser', val_gdmconf)

def allow_root_login(arg):
    '''  Allow/Forbid direct root login.'''
    securetty = ConfigFile.get_config_file(SECURETTY)
    kde = ConfigFile.get_config_file(KDE)
    gdm = ConfigFile.get_config_file(GDM)
    xdm = ConfigFile.get_config_file(XDM)

    val = {}
    val[kde] = kde.exists() and kde.get_match('auth required /lib/security/pam_listfile.so onerr=succeed item=user sense=deny file=/etc/bastille-no-login')
    val[gdm] = gdm.exists() and gdm.get_match('auth required /lib/security/pam_listfile.so onerr=succeed item=user sense=deny file=/etc/bastille-no-login')
    val[xdm] = xdm.exists() and xdm.get_match('auth required /lib/security/pam_listfile.so onerr=succeed item=user sense=deny file=/etc/bastille-no-login')
    num = 0
    for n in range(1, 7):
        s = 'tty' + str(n)
        if securetty.get_match(s):
            num = num + 1
            val[s] = 1
        else:
            val[s] = 0
        s = 'vc/' + str(n)
        if securetty.get_match(s):
            num = num + 1
            val[s] = 1
        else:
            val[s] = 0
    
    # don't lower security when not changing security level
    if _same_level:
        if (not kde.exists() or val[kde]) and (not gdm.exists() or val[gdm]) and (not xdm.exists() or val[xdm]) and num == 12:
            return

    if arg:
        if val[kde] or val[gdm] or val[xdm] or num != 12:
            _interactive and log(_('Allowing direct root login'))
        
            for cnf in (kde, gdm, xdm):
                if not (_same_level and val[cnf]):
                    cnf.exists() and cnf.remove_line_matching('^auth\s*required\s*/lib/security/pam_listfile.so.*bastille-no-login', 1)
        
            for n in range(1, 7):
                s = 'tty' + str(n)
                if not (_same_level and not val[s]):
                    securetty.replace_line_matching(s, s, 1)
                s = 'vc/' + str(n)
                if not (_same_level and not val[s]):
                    securetty.replace_line_matching(s, s, 1)
    else:
        if (kde.exists() and not val_kde) or (gdm.exists() and not val_gdm) or (xdm.exists() and not val_xdm) or num > 0:
            _interactive and log(_('Forbidding direct root login'))
        
            bastillenologin = ConfigFile.get_config_file(BASTILLENOLOGIN)
            bastillenologin.replace_line_matching('^\s*root', 'root', 1)
        
            for cnf in (kde, gdm, xdm):
                cnf.exists() and (cnf.replace_line_matching('^auth\s*required\s*/lib/security/pam_listfile.so.*bastille-no-login', 'auth required /lib/security/pam_listfile.so onerr=succeed item=user sense=deny file=/etc/bastille-no-login') or \
                                  cnf.insert_at(0, 'auth required /lib/security/pam_listfile.so onerr=succeed item=user sense=deny file=/etc/bastille-no-login'))
        
            securetty.remove_line_matching('.+', 1)

def allow_remote_root_login(arg):
    '''  Allow/Forbid remote root login.'''
    sshd_config = ConfigFile.get_config_file(SSHDCONFIG)

    if sshd_config.exists():
        val = sshd_config.get_match('^\s*PermitRootLogin\s+(no|yes)', '@1')
    else:
        val = None

    # don't lower security when not changing security level
    if _same_level:
        if val == 'no':
            return

    val = (val == 'yes')

    if arg:
        if val != arg:
            _interactive and log(_('Allowing remote root login'))
            sshd_config.exists() and sshd_config.replace_line_matching('^\s*PermitRootLogin\s+(no|yes)',
                                                                       'PermitRootLogin yes', 1)
    else:
        if val != arg:
            _interactive and log(_('Forbidding remote root login'))
            sshd_config.exists() and sshd_config.replace_line_matching('^\s*PermitRootLogin\s+(no|yes)',
                                                                       'PermitRootLogin no', 1)

def enable_pam_wheel_for_su(arg):
    '''   Enabling su only from members of the wheel group or allow su from any user.'''
    su = ConfigFile.get_config_file(SU)

    val = su.exists() and su.get_match('^auth\s+required\s+/lib/security/pam_wheel.so\s+use_uid\s*$')
    
    # don't lower security when not changing security level
    if _same_level:
        if val:
            return

    if arg:
        if not val:
            _interactive and log(_('Allowing su only from wheel group members'))
            try:
                ent = grp.getgrnam('wheel')
            except KeyError:
                error(_('no wheel group'))
                return
            members = ent[3]
            if members == [] or members == ['root']:
                _interactive and error(_('wheel group is empty'))
                return
            su.exists() and (su.replace_line_matching('^auth\s+required\s+/lib/security/pam_wheel.so\s+use_uid\s*$',
                                                      'auth       required     /lib/security/pam_wheel.so use_uid') or \
                             su.insert_after('^auth\s+required',
                                             'auth       required     /lib/security/pam_wheel.so use_uid'))
    else:
        if val:
            _interactive and log(_('Allowing su for all'))
            su.exists() and su.remove_line_matching('^auth\s+required\s+/lib/security/pam_wheel.so\s+use_uid\s*$')
    
def allow_issues(arg):
    '''  If \\fIarg\\fP = ALL allow /etc/issue and /etc/issue.net to exist. If \\fIarg\\fP = NONE no issues are
allowed else only /etc/issue is allowed.'''
    issue = ConfigFile.get_config_file(ISSUE, SUFFIX)
    issuenet = ConfigFile.get_config_file(ISSUENET, SUFFIX)

    val = issue.exists(1)
    valnet = issuenet.exists(1)

    # don't lower security when not changing security level
    if _same_level:
        if not val and not valnet:
            return
        if arg == ALL and not valnet:
            return

    if arg == ALL:
        if not (val and valnet):
            _interactive and log(_('Allowing network pre-login messages'))    
            issue.exists() and issue.get_lines()
            issuenet.exists() and issuenet.get_lines()
    else:
        if arg == NONE:
            if val:
                _interactive and log(_('Disabling pre-login message'))
                issue.exists(1) and issue.move(SUFFIX) and issue.modified()
        else:
            if not val:
                _interactive and log(_('Allowing pre-login message'))
                issue.exists() and issue.get_lines()
        if valnet:
            _interactive and log(_('Disabling network pre-login message'))
            issuenet.exists(1) and issuenet.move(SUFFIX)

def allow_autologin(arg):
    '''  Allow/Forbid autologin.'''
    autologin = ConfigFile.get_config_file(AUTOLOGIN)

    if autologin.exists():
        val = autologin.get_shell_variable('AUTOLOGIN')
    else:
        val = None
        
    # don't lower security when not changing security level
    if _same_level:
        if val == 'no':
            return

    if arg:
        if val != 'yes':
            _interactive and log(_('Allowing autologin'))
            autologin.exists() and autologin.set_shell_variable('AUTOLOGIN', 'yes')
    else:
        if val != 'no':
            _interactive and log(_('Forbidding autologin'))
            autologin.exists() and autologin.set_shell_variable('AUTOLOGIN', 'no')

def password_loader(value):
    'D'
    _interactive and log(_('Activating password in boot loader'))
    liloconf = ConfigFile.get_config_file(LILOCONF)
    liloconf.exists() and (liloconf.replace_line_matching('^password=', 'password="' + value + '"', 0, 1) or \
                           liloconf.insert_after('^boot=', 'password="' + value + '"')) and \
                           Perms.chmod(liloconf.path, 0600)
    # TODO encrypt password in grub
    menulst = ConfigFile.get_config_file(MENULST)
    menulst.exists() and (menulst.replace_line_matching('^password\s', 'password "' + value + '"') or \
                          menulst.insert_at(0, 'password "' + value + '"')) and \
                          Perms.chmod(menulst.path, 0600)
    # TODO add yaboot support
        
def nopassword_loader():
    'D'
    _interactive and log(_('Removing password in boot loader'))
    liloconf = ConfigFile.get_config_file(LILOCONF)
    liloconf.exists() and liloconf.remove_line_matching('^password=', 1)
    menulst = ConfigFile.get_config_file(MENULST)
    menulst.exists() and menulst.remove_line_matching('^password\s')

def enable_console_log(arg, expr='*.*', dev='tty12'):
    '''  Enable/Disable syslog reports to console 12. \\fIexpr\\fP is the
expression describing what to log (see syslog.conf(5) for more details) and
dev the device to report the log.'''
    
    syslogconf = ConfigFile.get_config_file(SYSLOGCONF)

    if syslogconf.exists():
        val = syslogconf.get_match('\s*[^#]+/dev/([^ ]+)', '@1')
    else:
        val = None

    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
        
    if arg:
        if dev != val:
            _interactive and log(_('Enabling log on console'))
            syslogconf.exists() and syslogconf.replace_line_matching('\s*[^#]+/dev/', expr + ' /dev/' + dev, 1)
    else:
        if val != None:
            _interactive and log(_('Disabling log on console'))
            syslogconf.exists() and syslogconf.remove_line_matching('\s*[^#]+/dev/')

CRON_ENTRY = '*/1 * * * *    root    /usr/share/msec/promisc_check.sh'
CRON_REGEX = '[^#]+/usr/share/msec/promisc_check.sh'

def enable_promisc_check(arg):
    '''  Activate/Disable ethernet cards promiscuity check.'''
    cron = ConfigFile.get_config_file(CRON)
    
    val = cron.exists() and cron.get_match(CRON_REGEX)
    
    # don't lower security when not changing security level
    if _same_level:
        if val == CRON_ENTRY:
            return
        
    if arg:
        if val != CRON_ENTRY:
            _interactive and log(_('Activating periodic promiscuity check'))
            cron.replace_line_matching(CRON_REGEX, CRON_ENTRY, 1)
    else:
        if val:
            _interactive and log(_('Disabling periodic promiscuity check'))
            cron.remove_line_matching('[^#]+/usr/share/msec/promisc_check.sh')

def enable_security_check(arg):
    '''   Activate/Disable daily security check.'''
    cron = ConfigFile.get_config_file(CRON)
    cron.remove_line_matching('[^#]+/usr/share/msec/security.sh')

    securitycron = ConfigFile.get_config_file(SECURITYCRON)

    val = securitycron.exists()
    
    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
        
    if arg:
        if not val:
            _interactive and log(_('Activating daily security check'))
            securitycron.symlink(SECURITYSH)
    else:
        if val:
            _interactive and log(_('Disabling daily security check'))
            securitycron.unlink()

ALL_REGEXP = '^ALL:ALL:DENY'
ALL_LOCAL_REGEXP = '^ALL:ALL EXCEPT 127\.0\.0\.1:DENY'
def authorize_services(arg):
    '''  Authorize all services controlled by tcp_wrappers (see hosts.deny(5)) if \\fIarg\\fP = ALL. Only local ones
if \\fIarg\\fP = LOCAL and none if \\fIarg\\fP = NONE. To authorize the services you need, use /etc/hosts.allow
(see hosts.allow(5)).'''
    hostsdeny = ConfigFile.get_config_file(HOSTSDENY)
    
    if hostsdeny.exists():
        if hostsdeny.get_match(ALL_REGEXP):
            val = NONE
        elif hostsdeny.get_match(ALL_LOCAL_REGEXP):
            val = LOCAL
        else:
            val = ALL
    else:
        val = ALL
        
    # don't lower security when not changing security level
    if _same_level:
        if val == NONE or (val == LOCAL and arg == ALL):
            return
        
    if arg == ALL:
        if arg != val:
            _interactive and log(_('Authorizing all services'))
            hostsdeny.remove_line_matching(ALL_REGEXP, 1)
            hostsdeny.remove_line_matching(ALL_LOCAL_REGEXP, 1)
    elif arg == NONE:
        if arg != val:
            _interactive and log(_('Disabling all services'))
            hostsdeny.remove_line_matching('^ALL:ALL EXCEPT 127\.0\.0\.1:DENY', 1)
            hostsdeny.replace_line_matching('^ALL:ALL:DENY', 'ALL:ALL:DENY', 1)
    elif arg == LOCAL:
        if arg != val:
            _interactive and log(_('Disabling non local services'))
            hostsdeny.remove_line_matching(ALL_REGEXP, 1)
            hostsdeny.replace_line_matching(ALL_LOCAL_REGEXP, 'ALL:ALL EXCEPT 127.0.0.1:DENY', 1)
    else:
        error(_('authorize_services invalid argument: %s') % arg)

# helper function for enable_ip_spoofing_protection, accept_icmp_echo, accept_broadcasted_icmp_echo,
# accept_bogus_error_responses and enable_log_strange_packets.
def set_zero_one_variable(file, variable, value, secure_value, one_msg, zero_msg):
    'D'
    f = ConfigFile.get_config_file(file)

    if f.exists():
        val = int(f.get_shell_variable(variable))
    else:
        val = None
        
    # don't lower security when not changing security level
    if _same_level:
        if val == secure_value:
            return
    
    if value != val:
        if value:
            msg = _(one_msg)
        else:
            msg = _(zero_msg)
        
        _interactive and log(msg)
        f.set_shell_variable(variable, value)

# the alert argument is kept for backward compatibility
def enable_ip_spoofing_protection(arg, alert=1):
    '''  Enable/Disable IP spoofing protection.'''
    set_zero_one_variable(SYSCTLCONF, 'net.ipv4.conf.all.rp_filter', arg, 1, 'Enabling ip spoofing protection', 'Disabling ip spoofing protection')

def enable_dns_spoofing_protection(arg, alert=1):
    ''' Enable/Disable name resolution spoofing protection.  If
\\fIalert\\fP is true, also reports to syslog.'''
    hostconf = ConfigFile.get_config_file(HOSTCONF)

    val = hostconf.exists() and hostconf.get_match('nospoof\s+on')
    
    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
        
    if arg:
        if not val:
            _interactive and log(_('Enabling name resolution spoofing protection'))
            hostconf.replace_line_matching('nospoof', 'nospoof on', 1)
            hostconf.replace_line_matching('spoofalert', 'spoofalert on', (alert != 0))
    else:
        if val:
            _interactive and log(_('Disabling name resolution spoofing protection'))
            hostconf.remove_line_matching('nospoof')
            hostconf.remove_line_matching('spoofalert')

def accept_icmp_echo(arg):
    '''   Accept/Refuse icmp echo.'''
    set_zero_one_variable(SYSCTLCONF, 'net.ipv4.icmp_echo_ignore_all', not arg, 1, 'Accepting icmp echo', 'Ignoring icmp echo')
    
def accept_broadcasted_icmp_echo(arg):
    '''   Accept/Refuse broadcasted icmp echo.'''
    set_zero_one_variable(SYSCTLCONF, 'net.ipv4.icmp_echo_ignore_broadcasts', not arg, 1, 'Accepting broadcasted icmp echo', 'Ignoring broadcasted icmp echo')
    
def accept_bogus_error_responses(arg):
    '''  Accept/Refuse bogus IPv4 error messages.'''
    set_zero_one_variable(SYSCTLCONF, 'net.ipv4.icmp_ignore_bogus_error_responses', not arg, 1, 'Accepting bogus icmp error responses', 'Ignoring bogus icmp error responses')
    
def enable_log_strange_packets(arg):
    '''  Enable/Disable the logging of IPv4 strange packets.'''
    set_zero_one_variable(SYSCTLCONF, 'net.ipv4.conf.all.log_martians', arg, 1, 'Enabling logging of strange packets', 'Disabling logging of strange packets')

def enable_libsafe(arg):
    '''  Enable/Disable libsafe if libsafe is found on the system.'''

    ldsopreload = ConfigFile.get_config_file(LDSOPRELOAD)

    val = ldsopreload.exists() and ldsopreload.get_match('/lib/libsafe.so.2')

    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
    
    if arg:
        if not val:
            if os.path.exists(Config.get_config('root', '') + '/lib/libsafe.so.2'):
                _interactive and log(_('Enabling libsafe'))
                ldsopreload.replace_line_matching('[^#]*libsafe', '/lib/libsafe.so.2', 1)
    else:
        if val:
            _interactive and log(_('Disabling libsafe'))
            ldsopreload.remove_line_matching('[^#]*libsafe')        

LENGTH_REGEXP = '^(password\s+required\s+/lib/security/pam_cracklib.so.*?)\sminlen=([0-9]+)\s(.*)'
NDIGITS_REGEXP = '^(password\s+required\s+/lib/security/pam_cracklib.so.*?)\sdcredit=([0-9]+)\s(.*)'
UCREDIT_REGEXP = '^(password\s+required\s+/lib/security/pam_cracklib.so.*?)\sucredit=([0-9]+)\s(.*)'

def password_length(length, ndigits=0, nupper=0):
    '''  Set the password minimum length and minimum number of digit and minimum number of capitalized letters.'''
    
    passwd = ConfigFile.get_config_file(PASSWD)

    if passwd.exists():
        val_length  = passwd.get_match(LENGTH_REGEXP, '@2')
        if val_length:
            val_length = int(val_length)

        val_ndigits = passwd.get_match(NDIGITS_REGEXP, '@2')
        if val_ndigits:
            val_ndigits = int(val_ndigits)

        val_ucredit = passwd.get_match(UCREDIT_REGEXP, '@2')
        if val_ucredit:
            val_ucredit = int(val_ucredit)
            
    # don't lower security when not changing security level
    if _same_level:
        if val_length > length and val_ndigits > ndigits and val_ucredit > nupper:
            return
        
        if val_length > length:
            length = val_length
            
        if val_ndigits > ndigits:
            ndigits = val_ndigits

        if val_ucredit > nupper:
            nupper = val_ucredit

    if passwd.exists() and (val_length != length or val_ndigits != ndigits or val_ucredit != nupper):
        _interactive and log(_('Setting minimum password length %d') % length)
        (passwd.replace_line_matching(LENGTH_REGEXP,
                                      '@1 minlen=%s @3' % length) or \
         passwd.replace_line_matching('^password\s+required\s+/lib/security/pam_cracklib.so.*',
                                      '@0 minlen=%s ' % length))
    
        (passwd.replace_line_matching(NDIGITS_REGEXP,
                                      '@1 dcredit=%s @3' % ndigits) or \
         passwd.replace_line_matching('^password\s+required\s+/lib/security/pam_cracklib.so.*',
                                      '@0 dcredit=%s ' % ndigits))
    
        (passwd.replace_line_matching(UCREDIT_REGEXP,
                                      '@1 ucredit=%s @3' % nupper) or \
         passwd.replace_line_matching('^password\s+required\s+/lib/security/pam_cracklib.so.*',
                                      '@0 ucredit=%s ' % nupper))

PASSWORD_REGEXP = '^\s*auth\s+sufficient\s+/lib/security/pam_permit.so'
def enable_password(arg):
    '''  Use password to authenticate users.'''
    system_auth = ConfigFile.get_config_file(SYSTEM_AUTH)

    val = system_auth.exists() and system_auth.get_match(PASSWORD_REGEXP)
    
    # don't lower security when not changing security level
    if _same_level:
        if not val:
            return
        
    if arg:
        if val:
            _interactive and log(_('Using password to authenticate users'))
            system_auth.remove_line_matching(PASSWORD_REGEXP)
    else:
        if not val:
            _interactive and log(_('Don\'t use password to authenticate users'))
            system_auth.replace_line_matching(PASSWORD_REGEXP, 'auth        sufficient    /lib/security/pam_permit.so') or \
            system_auth.insert_before('auth\s+sufficient', 'auth        sufficient    /lib/security/pam_permit.so')

SULOGIN_REGEXP = '~~:S:wait:/sbin/sulogin'
def enable_sulogin(arg):
    '''   Enable/Disable sulogin(8) in single user level.'''
    inittab = ConfigFile.get_config_file(INITTAB)

    val = inittab.exists() and inittab.get_match(SULOGIN_REGEXP)
    
    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
        
    if arg:
        if not val:
            _interactive and log(_('Enabling sulogin in single user runlevel'))
            inittab.replace_line_matching('[^#]+:S:', '~~:S:wait:/sbin/sulogin', 1)
    else:
        if val:
            _interactive and log(_('Disabling sulogin in single user runlevel'))
            inittab.remove_line_matching('~~:S:wait:/sbin/sulogin')

def enable_msec_cron(arg):
    '''  Enable/Disable msec hourly security check.'''
    mseccron = ConfigFile.get_config_file(MSECCRON)

    val = mseccron.exists()
    
    # don't lower security when not changing security level
    if _same_level:
        if val:
            return
        
    if arg:
        if arg != val:
            _interactive and log(_('Enabling msec periodic runs'))
            mseccron.symlink(MSECBIN)
    else:
        if arg != val:
            _interactive and log(_('Disabling msec periodic runs'))
            mseccron.unlink()

def enable_at_crontab(arg):
    '''  Enable/Disable crontab and at for users. Put allowed users in /etc/cron.allow and /etc/at.allow
(see man at(1) and crontab(1)).'''
    cronallow = ConfigFile.get_config_file(CRONALLOW)
    atallow = ConfigFile.get_config_file(ATALLOW)

    val_cronallow = cronallow.exists() and cronallow.get_match('root')
    val_atallow = atallow.exists() and atallow.get_match('root')
    
    # don't lower security when not changing security level
    if _same_level:
        if val_cronallow and val_atallow:
            return

    if arg:
        if val_cronallow or val_atallow:
            _interactive and log(_('Enabling crontab and at'))
            if not (_same_level and val_cronallow):
                cronallow.exists() and cronallow.move(SUFFIX)
            if not (_same_level and val_atallow):
                atallow.exists() and atallow.move(SUFFIX)
    else:
        if not val_cronallow or not val_atallow:
            _interactive and log(_('Disabling crontab and at'))
            cronallow.replace_line_matching('root', 'root', 1)
            atallow.replace_line_matching('root', 'root', 1)

maximum_regex = re.compile('^Maximum:\s*([0-9]+|-1)', re.MULTILINE)
inactive_regex = re.compile('^Inactive:\s*(-?[0-9]+)', re.MULTILINE)
no_aging_list = []

def no_password_aging_for(name):
    '''D Add the name as an exception to the handling of password aging by msec.'''
    no_aging_list.append(name)
    
# TODO FL Sat Dec 29 20:18:20 2001
# replace chage calls and /etc/shadow parsing by a python API to the shadow functions.
def password_aging(max, inactive=-1):
    '''  Set password aging to \\fImax\\fP days and delay to change to \\fIinactive\\fP.'''
    uid_min = 500
    _interactive and log(_('Setting password maximum aging for new user to %d') % max)
    logindefs = ConfigFile.get_config_file(LOGINDEFS)
    if logindefs.exists():
        logindefs.replace_line_matching('^\s*PASS_MAX_DAYS', 'PASS_MAX_DAYS ' + str(max), 1)
        uid_min = logindefs.get_match('^\s*UID_MIN\s+([0-9]+)', '@1')
        if uid_min:
            uid_min = int(uid_min)
    shadow = ConfigFile.get_config_file(SHADOW)
    if shadow.exists():
        _interactive and log(_('Setting password maximum aging for root and users with id greater than %d to %d and delay to %d days') % (uid_min, max, inactive))
        for line in shadow.get_lines():
            field = string.split(line, ':')
            if len(field) < 2:
                continue
            name = field[0]
            password = field[1]
            if name in no_aging_list:
                _interactive and log(_('User %s in password aging exception list') % (name,))
                continue
            try:
                entry = pwd.getpwnam(name)
            except KeyError:
                error(_('User %s in shadow but not in passwd file') % name)
                continue
            if (len(password) > 0 and password[0] != '!') and password != '*' and password != 'x' and (entry[2] >= uid_min or entry[2] == 0):
                cmd = '/usr/bin/chage -l %s' % entry[0]
                ret = commands.getstatusoutput(cmd)
                _interactive and log(_('got current maximum password aging for user %s with command \'%s\'') % (entry[0], cmd))
                if ret[0] == 0:
                    res = maximum_regex.search(ret[1])
                    res2 = inactive_regex.search(ret[1])
                    if res and res2:
                        current_max = int(res.group(1))
                        current_inactive = int(res2.group(1))
                        new_max = max
                        new_inactive = inactive
                        # don't lower security when not changing security level
                        if _same_level:
                            if current_max < max and current_inactive < inactive:
                                continue
                            if current_max < max:
                                new_max = current_max
                            if current_inactive < inactive:
                                new_inactive = current_inactive
                        if new_max != current_max or current_inactive != new_inactive:
                            cmd = '/usr/bin/chage -M %d -I %d %s' % (new_max, new_inactive, entry[0])
                            ret = commands.getstatusoutput(cmd)
                            log(_('changed maximum password aging for user %s with command %s') % (entry[0], cmd))
                            if ret[0] != 0:
                                error(ret[1])
                    else:
                        error(_('unable to parse chage output'))
                else:
                    error(_('unable to run chage: %s') % ret[1])

def set_security_conf(var, value):
    '''1 Set the variable \\fIvar\\fP to the value \\fIvalue\\fP in /var/lib/msec/security.conf.
The best way to override the default setting is to use create /etc/security/msec/security.conf
with the value you want.

The following variables are currentrly recognized by msec:

CHECK_UNOWNED if set to yes, report unowned files.

CHECK_SHADOW if set to yes, check empty password in /etc/shadow.

CHECK_SUID_MD5 if set to yes, verify checksum of the suid/sgid files.

CHECK_SECURITY if set to yes, run the daily security checks.

CHECK_PASSWD if set to yes, check for empty password, or a password while it should be in /etc/shadow or other users with id 0.

SYSLOG_WARN if set to yes, report check result to syslog.

CHECK_SUID_ROOT if set to yes, check additions/removals of suid root files.

CHECK_PERMS if set to yes, check permissions of files in the users' home.

CHKROOTKIT_CHECK if set to yes, run chkrootkit checks.

CHECK_PROMISC if set to yes, check if the network devices are in promiscuous mode.

RPM_CHECK if set to yes, run some checks against the rpm database.

TTY_WARN if set to yes, reports check result to tty.

CHECK_WRITEABLE if set to yes, check files/directories writable by everybody.

MAIL_WARN if set to yes, report check result by mail.

MAIL_USER if set, send the mail report to this email address else send it to root.

CHECK_OPEN_PORT if set to yes, check open ports.

CHECK_SUID_GROUP if set to yes, check additions/removals of sgid files.
'''
    securityconf = ConfigFile.get_config_file(SECURITYCONF)
    securityconf.set_shell_variable(var, value)

# various

def set_interactive(v):
    "D"
    
    global _interactive
    
    _interactive = v

# libmsec.py ends here