Bir SELinux ilke modülü aşağıdaki adımlarla oluşturulur:
- bir dizi politika kuralı oluşturun:
audit2allow
- derlemek:
checkmodule
- inşa etmek:
semodule_package
http://wiki.centos.org/HowTos/SELinux
postgreylocal.te
Belows içerikli bir dosyam olduğu varsayılarak :
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
ilke modülü aşağıdakilerle oluşturulacaktır:
# checkmodule -M -m -o postgreylocal.mod postgreylocal.te
# semodule_package -m postgreylocal.mod -o postgreylocal.pp
Bu ilke modülünü açmak için, dosyayı ayıklamak üzere semodule_unpackage adlı bir araca ihtiyacınız var .mod
ve sonra dismod
ikili modülü metinsel gösterime ayırmak için kullanın .
Gentoo'mda aşağıdaki paketlerin yüklenmesi gerekiyor:
[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
İlk olarak, modülü .pp
dosyadan çıkarın :
# semodule_unpackage postgreylocal.pp postgreylocal.mod
ve ikincisi, ile sökün 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):
sedismod
. Bu birlikte zaten varcheckpolicy
vesemodule_unpack
varsayılan yükleme ile. Btw,semodule_unpackage foo.pp foo.mod foo.fc
sizin aracılığınızla filecontexts dosyasını ayıklayabilirsiniz.