2005-04-16 18:20:36 -04:00
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#
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# Security configuration
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#
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menu "Security options"
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config KEYS
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bool "Enable access key retention support"
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help
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This option provides support for retaining authentication tokens and
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access keys in the kernel.
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It also includes provision of methods by which such keys might be
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associated with a process so that network filesystems, encryption
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support and the like can find them.
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Furthermore, a special type of key is available that acts as keyring:
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a searchable sequence of keys. Each process is equipped with access
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to five standard keyrings: UID-specific, GID-specific, session,
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process and thread.
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If you are unsure as to whether this is required, answer N.
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config KEYS_DEBUG_PROC_KEYS
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2006-06-26 03:24:56 -04:00
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bool "Enable the /proc/keys file by which keys may be viewed"
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2005-04-16 18:20:36 -04:00
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depends on KEYS
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help
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2006-06-26 03:24:56 -04:00
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This option turns on support for the /proc/keys file - through which
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can be listed all the keys on the system that are viewable by the
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reading process.
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2005-04-16 18:20:36 -04:00
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2006-06-26 03:24:56 -04:00
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The only keys included in the list are those that grant View
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permission to the reading process whether or not it possesses them.
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Note that LSM security checks are still performed, and may further
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filter out keys that the current process is not authorised to view.
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Only key attributes are listed here; key payloads are not included in
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the resulting table.
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If you are unsure as to whether this is required, answer N.
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2005-04-16 18:20:36 -04:00
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config SECURITY
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bool "Enable different security models"
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2005-08-22 12:20:50 -04:00
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depends on SYSFS
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2005-04-16 18:20:36 -04:00
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help
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This allows you to choose different security modules to be
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configured into your kernel.
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If this option is not selected, the default Linux security
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model will be used.
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If you are unsure how to answer this question, answer N.
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config SECURITY_NETWORK
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bool "Socket and Networking Security Hooks"
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depends on SECURITY
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help
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This enables the socket and networking security hooks.
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If enabled, a security module can use these hooks to
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implement socket and networking access controls.
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If you are unsure how to answer this question, answer N.
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[LSM-IPSec]: Security association restriction.
This patch series implements per packet access control via the
extension of the Linux Security Modules (LSM) interface by hooks in
the XFRM and pfkey subsystems that leverage IPSec security
associations to label packets. Extensions to the SELinux LSM are
included that leverage the patch for this purpose.
This patch implements the changes necessary to the XFRM subsystem,
pfkey interface, ipv4/ipv6, and xfrm_user interface to restrict a
socket to use only authorized security associations (or no security
association) to send/receive network packets.
Patch purpose:
The patch is designed to enable access control per packets based on
the strongly authenticated IPSec security association. Such access
controls augment the existing ones based on network interface and IP
address. The former are very coarse-grained, and the latter can be
spoofed. By using IPSec, the system can control access to remote
hosts based on cryptographic keys generated using the IPSec mechanism.
This enables access control on a per-machine basis or per-application
if the remote machine is running the same mechanism and trusted to
enforce the access control policy.
Patch design approach:
The overall approach is that policy (xfrm_policy) entries set by
user-level programs (e.g., setkey for ipsec-tools) are extended with a
security context that is used at policy selection time in the XFRM
subsystem to restrict the sockets that can send/receive packets via
security associations (xfrm_states) that are built from those
policies.
A presentation available at
www.selinux-symposium.org/2005/presentations/session2/2-3-jaeger.pdf
from the SELinux symposium describes the overall approach.
Patch implementation details:
On output, the policy retrieved (via xfrm_policy_lookup or
xfrm_sk_policy_lookup) must be authorized for the security context of
the socket and the same security context is required for resultant
security association (retrieved or negotiated via racoon in
ipsec-tools). This is enforced in xfrm_state_find.
On input, the policy retrieved must also be authorized for the socket
(at __xfrm_policy_check), and the security context of the policy must
also match the security association being used.
The patch has virtually no impact on packets that do not use IPSec.
The existing Netfilter (outgoing) and LSM rcv_skb hooks are used as
before.
Also, if IPSec is used without security contexts, the impact is
minimal. The LSM must allow such policies to be selected for the
combination of socket and remote machine, but subsequent IPSec
processing proceeds as in the original case.
Testing:
The pfkey interface is tested using the ipsec-tools. ipsec-tools have
been modified (a separate ipsec-tools patch is available for version
0.5) that supports assignment of xfrm_policy entries and security
associations with security contexts via setkey and the negotiation
using the security contexts via racoon.
The xfrm_user interface is tested via ad hoc programs that set
security contexts. These programs are also available from me, and
contain programs for setting, getting, and deleting policy for testing
this interface. Testing of sa functions was done by tracing kernel
behavior.
Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-14 02:12:27 -05:00
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config SECURITY_NETWORK_XFRM
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bool "XFRM (IPSec) Networking Security Hooks"
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depends on XFRM && SECURITY_NETWORK
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help
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This enables the XFRM (IPSec) networking security hooks.
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If enabled, a security module can use these hooks to
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implement per-packet access controls based on labels
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derived from IPSec policy. Non-IPSec communications are
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designated as unlabelled, and only sockets authorized
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to communicate unlabelled data can send without using
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IPSec.
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If you are unsure how to answer this question, answer N.
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2005-04-16 18:20:36 -04:00
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config SECURITY_CAPABILITIES
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2007-10-17 02:31:32 -04:00
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bool "Default Linux Capabilities"
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2005-04-16 18:20:36 -04:00
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depends on SECURITY
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2008-01-29 08:04:43 -05:00
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default y
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2005-04-16 18:20:36 -04:00
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help
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This enables the "default" Linux capabilities functionality.
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If you are unsure how to answer this question, answer Y.
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Implement file posix capabilities
Implement file posix capabilities. This allows programs to be given a
subset of root's powers regardless of who runs them, without having to use
setuid and giving the binary all of root's powers.
This version works with Kaigai Kohei's userspace tools, found at
http://www.kaigai.gr.jp/index.php. For more information on how to use this
patch, Chris Friedhoff has posted a nice page at
http://www.friedhoff.org/fscaps.html.
Changelog:
Nov 27:
Incorporate fixes from Andrew Morton
(security-introduce-file-caps-tweaks and
security-introduce-file-caps-warning-fix)
Fix Kconfig dependency.
Fix change signaling behavior when file caps are not compiled in.
Nov 13:
Integrate comments from Alexey: Remove CONFIG_ ifdef from
capability.h, and use %zd for printing a size_t.
Nov 13:
Fix endianness warnings by sparse as suggested by Alexey
Dobriyan.
Nov 09:
Address warnings of unused variables at cap_bprm_set_security
when file capabilities are disabled, and simultaneously clean
up the code a little, by pulling the new code into a helper
function.
Nov 08:
For pointers to required userspace tools and how to use
them, see http://www.friedhoff.org/fscaps.html.
Nov 07:
Fix the calculation of the highest bit checked in
check_cap_sanity().
Nov 07:
Allow file caps to be enabled without CONFIG_SECURITY, since
capabilities are the default.
Hook cap_task_setscheduler when !CONFIG_SECURITY.
Move capable(TASK_KILL) to end of cap_task_kill to reduce
audit messages.
Nov 05:
Add secondary calls in selinux/hooks.c to task_setioprio and
task_setscheduler so that selinux and capabilities with file
cap support can be stacked.
Sep 05:
As Seth Arnold points out, uid checks are out of place
for capability code.
Sep 01:
Define task_setscheduler, task_setioprio, cap_task_kill, and
task_setnice to make sure a user cannot affect a process in which
they called a program with some fscaps.
One remaining question is the note under task_setscheduler: are we
ok with CAP_SYS_NICE being sufficient to confine a process to a
cpuset?
It is a semantic change, as without fsccaps, attach_task doesn't
allow CAP_SYS_NICE to override the uid equivalence check. But since
it uses security_task_setscheduler, which elsewhere is used where
CAP_SYS_NICE can be used to override the uid equivalence check,
fixing it might be tough.
task_setscheduler
note: this also controls cpuset:attach_task. Are we ok with
CAP_SYS_NICE being used to confine to a cpuset?
task_setioprio
task_setnice
sys_setpriority uses this (through set_one_prio) for another
process. Need same checks as setrlimit
Aug 21:
Updated secureexec implementation to reflect the fact that
euid and uid might be the same and nonzero, but the process
might still have elevated caps.
Aug 15:
Handle endianness of xattrs.
Enforce capability version match between kernel and disk.
Enforce that no bits beyond the known max capability are
set, else return -EPERM.
With this extra processing, it may be worth reconsidering
doing all the work at bprm_set_security rather than
d_instantiate.
Aug 10:
Always call getxattr at bprm_set_security, rather than
caching it at d_instantiate.
[morgan@kernel.org: file-caps clean up for linux/capability.h]
[bunk@kernel.org: unexport cap_inode_killpriv]
Signed-off-by: Serge E. Hallyn <serue@us.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Andrew Morgan <morgan@kernel.org>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 02:31:36 -04:00
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config SECURITY_FILE_CAPABILITIES
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bool "File POSIX Capabilities (EXPERIMENTAL)"
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depends on (SECURITY=n || SECURITY_CAPABILITIES!=n) && EXPERIMENTAL
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default n
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help
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This enables filesystem capabilities, allowing you to give
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binaries a subset of root's powers without using setuid 0.
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If in doubt, answer N.
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2005-04-16 18:20:36 -04:00
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config SECURITY_ROOTPLUG
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bool "Root Plug Support"
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depends on USB=y && SECURITY
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2005-04-16 18:20:36 -04:00
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help
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This is a sample LSM module that should only be used as such.
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It prevents any programs running with egid == 0 if a specific
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USB device is not present in the system.
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See <http://www.linuxjournal.com/article.php?sid=6279> for
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more information about this module.
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If you are unsure how to answer this question, answer N.
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source security/selinux/Kconfig
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endmenu
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