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2 lsm capabilities module, 3 lsm apparmor module, 8 apparmor – IBM Novell 10 SP1 EAL4 User Manual

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LSM adds a general security system call that simply invokes the sys_security hook. This system call

and hook permits security modules to implement new system calls for security-aware applications.

5.7.2 LSM capabilities module

The LSM kernel patch moves most of the existing POSIX.1e capabilities logic into an optional security
module stored in the file security/capability.c. This change allows users who do not want to use

capabilities to omit this code entirely from their kernel, instead using the dummy module for traditional super
user logic or any other module that they desire.
The capabilities logic for computing process capabilities on execve and set*uid, checking capabilities for a
particular process, saving and checking capabilities for netlink messages, and handling the capget and
capset system calls, have been moved into the capabilities module.

5.7.3 LSM AppArmor module

SLES includes AppArmor, which is an add-on security module. AppArmor provides application containment
functionality. AppArmor is described in the next section. For more information about AppArmor, see

http://www.novell.com/linux/security/apparmor/

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5.8 AppArmor

The AppArmor logical subsystem consists of

The AppArmor access control functions, provided by the AppArmor LSM module. The AppArmor
LSM modules provides security functions that implement additional access control checks when
subjects access objects.

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Figure 5-76: LSM hook architecture