Bagaimana cara melihat konten paket kebijakan SELinux

Seperti judulnya, bagaimana cara melihat konten paket kebijakan SELinux? File yang dihasilkan diakhiri dengan .pp. Saya menjalankan pada centos 6, tapi saya kira itu cara yang sama pada distro "semua".

Sebagai contoh

    cp /usr/share/selinux/targeted/cobbler.pp.bz2 ~
    bunzip2 cobbler.pp.bz2 
    MAGIC_SELINUX_CMD cobbler.pp

Modul kebijakan SELinux dibangun dengan langkah-langkah berikut:

1. menghasilkan seperangkat aturan kebijakan: audit2allow
2. menyusun: checkmodule
3. membangun: semodule_package

http://wiki.centos.org/HowTos/SELinux

Dengan asumsi bahwa saya memiliki postgreylocal.tefile dengan konten berikut:

module postgreylocal 1.0;
require {
        type postfix_smtpd_t;
        type postfix_spool_t;
        type initrc_t;
        class sock_file write;
        class unix_stream_socket connectto;
}
#============= postfix_smtpd_t ==============
allow postfix_smtpd_t initrc_t:unix_stream_socket connectto;
allow postfix_smtpd_t postfix_spool_t:sock_file write; 

postgreylocal.pp modul kebijakan akan dibuat dengan:

# checkmodule -M -m -o postgreylocal.mod postgreylocal.te
# semodule_package -m postgreylocal.mod -o postgreylocal.pp 

Untuk membongkar modul kebijakan ini, Anda memerlukan alat yang disebut semodule_unpackage untuk mengekstrak .modfile dan kemudian gunakan dismoduntuk membongkar modul biner ke representasi tekstual.

Di Gentoo saya, paket-paket berikut perlu diinstal:

[I] sys-apps/policycoreutils
     Available versions:  [M]2.0.82 [M](~)2.0.82-r1 [M](~)2.0.85 [M](~)2.1.0 {M}(~)2.1.0-r1
     Installed versions:  2.1.0-r1(05:12:27 PM 10/14/2011)
     Homepage:            http://userspace.selinuxproject.org
     Description:         SELinux core utilities

[I] sys-apps/checkpolicy
     Available versions:  [M]2.0.21 [M](~)2.0.23 {M}(~)2.1.0 {debug}
     Installed versions:  2.1.0(01:27:53 PM 10/14/2011)(-debug)
     Homepage:            http://userspace.selinuxproject.org
     Description:         SELinux policy compiler

[I] sys-libs/libsepol
     Available versions:  [M]2.0.41!t [M](~)2.0.42!t {M}(~)2.1.0!t
     Installed versions:  2.1.0!t(01:25:43 PM 10/14/2011)
     Homepage:            http://userspace.selinuxproject.org
     Description:         SELinux binary policy representation library

Pertama, ekstrak modul dari .ppfile:

# semodule_unpackage postgreylocal.pp postgreylocal.mod

dan kedua, bongkar dengan dismod:

# cd checkpolicy-2.1.0/test/
# ls
dismod.c  dispol.c  Makefile
# make
cc -g -Wall -O2 -pipe -I/usr/include   -c -o dispol.o dispol.c
dispol.c: In function ‘main’:
dispol.c:438:8: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
dispol.c:465:9: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
dispol.c:476:9: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
dispol.c:500:9: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
cc   dispol.o  -lfl -lsepol -lselinux /usr/lib/libsepol.a -L/usr/lib -o dispol
cc -g -Wall -O2 -pipe -I/usr/include   -c -o dismod.o dismod.c
dismod.c: In function ‘main’:
dismod.c:913:8: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
dismod.c:982:9: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
dismod.c: In function ‘link_module’:
dismod.c:787:7: warning: ignoring return value of ‘fgets’, declared with attribute warn_unused_result
cc   dismod.o  -lfl -lsepol -lselinux /usr/lib/libsepol.a -L/usr/lib -o dismod
# ls
dismod  dismod.c  dismod.o  dispol  dispol.c  dispol.o  Makefile

./dismod postgreylocal.pp
Reading policy...
libsepol.policydb_index_others: security:  0 users, 1 roles, 3 types, 0 bools
libsepol.policydb_index_others: security: 0 sens, 0 cats
libsepol.policydb_index_others: security:  2 classes, 0 rules, 0 cond rules
libsepol.policydb_index_others: security:  0 users, 1 roles, 3 types, 0 bools
libsepol.policydb_index_others: security: 0 sens, 0 cats
libsepol.policydb_index_others: security:  2 classes, 0 rules, 0 cond rules
Binary policy module file loaded.
Module name: postgreylocal
Module version: 1.0


Select a command:
1)  display unconditional AVTAB
2)  display conditional AVTAB
3)  display users
4)  display bools
5)  display roles
6)  display types, attributes, and aliases
7)  display role transitions
8)  display role allows
9)  Display policycon
0)  Display initial SIDs

a)  Display avrule requirements
b)  Display avrule declarations
c)  Display policy capabilities
l)  Link in a module
u)  Display the unknown handling setting
F)  Display filename_trans rules

f)  set output file
m)  display menu
q)  quit

Command ('m' for menu):  1
unconditional avtab:
--- begin avrule block ---
decl 1:
  allow [postfix_smtpd_t] [initrc_t] : [unix_stream_socket] { connectto };
  allow [postfix_smtpd_t] [postfix_spool_t] : [sock_file] { write };

Command ('m' for menu):  a
avrule block requirements:
--- begin avrule block ---
decl 1:
commons: <empty>
classes: sock_file{  write } unix_stream_socket{  connectto }
roles  : <empty>
types  : postfix_smtpd_t postfix_spool_t initrc_t
users  : <empty>
bools  : <empty>
levels : <empty>
cats   : <empty>

Command ('m' for menu):  

Apakah Anda mendapat masalah wrong magic number for module package: expected 0xf97cff8f, got 0x39685a42?

File .pp disimpan secara internal dalam format bzip2, jadi Anda harus melakukan bzip2 -cdk policyfile.pp > policyfile.pp.out SEBELUM semodule_unpackage policyfile.pp.out policyfile.mod.