Commit Graph

156 Commits

Author SHA1 Message Date
Paul Moore
6c5b3fc014 selinux: Cache NetLabel secattrs in the socket's security struct
Previous work enabled the use of address based NetLabel selectors, which
while highly useful, brought the potential for additional per-packet overhead
when used.  This patch attempts to mitigate some of that overhead by caching
the NetLabel security attribute struct within the SELinux socket security
structure.  This should help eliminate the need to recreate the NetLabel
secattr structure for each packet resulting in less overhead.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
2008-10-10 10:16:33 -04:00
Paul Moore
014ab19a69 selinux: Set socket NetLabel based on connection endpoint
Previous work enabled the use of address based NetLabel selectors, which while
highly useful, brought the potential for additional per-packet overhead when
used.  This patch attempts to solve that by applying NetLabel socket labels
when sockets are connect()'d.  This should alleviate the per-packet NetLabel
labeling for all connected sockets (yes, it even works for connected DGRAM
sockets).

Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
2008-10-10 10:16:33 -04:00
Paul Moore
948bf85c1b netlabel: Add functionality to set the security attributes of a packet
This patch builds upon the new NetLabel address selector functionality by
providing the NetLabel KAPI and CIPSO engine support needed to enable the
new packet-based labeling.  The only new addition to the NetLabel KAPI at
this point is shown below:

 * int netlbl_skbuff_setattr(skb, family, secattr)

... and is designed to be called from a Netfilter hook after the packet's
IP header has been populated such as in the FORWARD or LOCAL_OUT hooks.

This patch also provides the necessary SELinux hooks to support this new
functionality.  Smack support is not currently included due to uncertainty
regarding the permissions needed to expand the Smack network access controls.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Reviewed-by: James Morris <jmorris@namei.org>
2008-10-10 10:16:32 -04:00
Paul Moore
dfaebe9825 selinux: Fix missing calls to netlbl_skbuff_err()
At some point I think I messed up and dropped the calls to netlbl_skbuff_err()
which are necessary for CIPSO to send error notifications to remote systems.
This patch re-introduces the error handling calls into the SELinux code.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
2008-10-10 10:16:31 -04:00
KaiGai Kohei
d9250dea3f SELinux: add boundary support and thread context assignment
The purpose of this patch is to assign per-thread security context
under a constraint. It enables multi-threaded server application
to kick a request handler with its fair security context, and
helps some of userspace object managers to handle user's request.

When we assign a per-thread security context, it must not have wider
permissions than the original one. Because a multi-threaded process
shares a single local memory, an arbitary per-thread security context
also means another thread can easily refer violated information.

The constraint on a per-thread security context requires a new domain
has to be equal or weaker than its original one, when it tries to assign
a per-thread security context.

Bounds relationship between two types is a way to ensure a domain can
never have wider permission than its bounds. We can define it in two
explicit or implicit ways.

The first way is using new TYPEBOUNDS statement. It enables to define
a boundary of types explicitly. The other one expand the concept of
existing named based hierarchy. If we defines a type with "." separated
name like "httpd_t.php", toolchain implicitly set its bounds on "httpd_t".

This feature requires a new policy version.
The 24th version (POLICYDB_VERSION_BOUNDARY) enables to ship them into
kernel space, and the following patch enables to handle it.

Signed-off-by: KaiGai Kohei <kaigai@ak.jp.nec.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-08-29 00:33:33 +10:00
James Morris
089be43e40 Revert "SELinux: allow fstype unknown to policy to use xattrs if present"
This reverts commit 811f379927.

From Eric Paris:

"Please drop this patch for now.  It deadlocks on ntfs-3g.  I need to
rework it to handle fuse filesystems better.  (casey was right)"
2008-07-15 18:32:49 +10:00
Eric Paris
811f379927 SELinux: allow fstype unknown to policy to use xattrs if present
Currently if a FS is mounted for which SELinux policy does not define an
fs_use_* that FS will either be genfs labeled or not labeled at all.
This decision is based on the existence of a genfscon rule in policy and
is irrespective of the capabilities of the filesystem itself.  This
patch allows the kernel to check if the filesystem supports security
xattrs and if so will use those if there is no fs_use_* rule in policy.
An fstype with a no fs_use_* rule but with a genfs rule will use xattrs
if available and will follow the genfs rule.

This can be particularly interesting for things like ecryptfs which
actually overlays a real underlying FS.  If we define excryptfs in
policy to use xattrs we will likely get this wrong at times, so with
this path we just don't need to define it!

Overlay ecryptfs on top of NFS with no xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses genfs_contexts
Overlay ecryptfs on top of ext4 with xattr support:
SELinux: initialized (dev ecryptfs, type ecryptfs), uses xattr

It is also useful as the kernel adds new FS we don't need to add them in
policy if they support xattrs and that is how we want to handle them.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:02:04 +10:00
James Morris
feb2a5b82d SELinux: remove inherit field from inode_security_struct
Remove inherit field from inode_security_struct, per Stephen Smalley:
"Let's just drop inherit altogether - dead field."

Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:01:38 +10:00
Richard Kennedy
fdeb05184b SELinux: reorder inode_security_struct to increase objs/slab on 64bit
reorder inode_security_struct to remove padding on 64 bit builds

size reduced from 72 to 64 bytes increasing objects per slab to 64.

Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:01:37 +10:00
Eric Paris
f526971078 SELinux: keep the code clean formating and syntax
Formatting and syntax changes

whitespace, tabs to spaces, trailing space
put open { on same line as struct def
remove unneeded {} after if statements
change printk("Lu") to printk("llu")
convert asm/uaccess.h to linux/uaacess.h includes
remove unnecessary asm/bug.h includes
convert all users of simple_strtol to strict_strtol

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:01:36 +10:00
Stephen Smalley
12b29f3455 selinux: support deferred mapping of contexts
Introduce SELinux support for deferred mapping of security contexts in
the SID table upon policy reload, and use this support for inode
security contexts when the context is not yet valid under the current
policy.  Only processes with CAP_MAC_ADMIN + mac_admin permission in
policy can set undefined security contexts on inodes.  Inodes with
such undefined contexts are treated as having the unlabeled context
until the context becomes valid upon a policy reload that defines the
context.  Context invalidation upon policy reload also uses this
support to save the context information in the SID table and later
recover it upon a subsequent policy reload that defines the context
again.

This support is to enable package managers and similar programs to set
down file contexts unknown to the system policy at the time the file
is created in order to better support placing loadable policy modules
in packages and to support build systems that need to create images of
different distro releases with different policies w/o requiring all of
the contexts to be defined or legal in the build host policy.

With this patch applied, the following sequence is possible, although
in practice it is recommended that this permission only be allowed to
specific program domains such as the package manager.

# rmdir baz
# rm bar
# touch bar
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument
# cat setundefined.te
policy_module(setundefined, 1.0)
require {
	type unconfined_t;
	type unlabeled_t;
}
files_type(unlabeled_t)
allow unconfined_t self:capability2 mac_admin;
# make -f /usr/share/selinux/devel/Makefile setundefined.pp
# semodule -i setundefined.pp
# chcon -t foo_exec_t bar # foo_exec_t is not yet defined
# mkdir -Z system_u:object_r:foo_exec_t baz
# ls -Zd bar baz
-rw-r--r--  root root system_u:object_r:unlabeled_t    bar
drwxr-xr-x  root root system_u:object_r:unlabeled_t    baz
# cat foo.te
policy_module(foo, 1.0)
type foo_exec_t;
files_type(foo_exec_t)
# make -f /usr/share/selinux/devel/Makefile foo.pp
# semodule -i foo.pp # defines foo_exec_t
# ls -Zd bar baz
-rw-r--r--  root root user_u:object_r:foo_exec_t       bar
drwxr-xr-x  root root system_u:object_r:foo_exec_t    baz
# semodule -r foo
# ls -Zd bar baz
-rw-r--r--  root root system_u:object_r:unlabeled_t    bar
drwxr-xr-x  root root system_u:object_r:unlabeled_t    baz
# semodule -i foo.pp
# ls -Zd bar baz
-rw-r--r--  root root user_u:object_r:foo_exec_t       bar
drwxr-xr-x  root root system_u:object_r:foo_exec_t    baz
# semodule -r setundefined foo
# chcon -t foo_exec_t bar # no longer defined and not allowed
chcon: failed to change context of `bar' to `system_u:object_r:foo_exec_t': Invalid argument
# rmdir baz
# mkdir -Z system_u:object_r:foo_exec_t baz
mkdir: failed to set default file creation context to `system_u:object_r:foo_exec_t': Invalid argument

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-07-14 15:01:34 +10:00
David Howells
7bf570dc8d Security: Make secctx_to_secid() take const secdata
Make secctx_to_secid() take constant secdata.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 13:22:56 -07:00
David Howells
8f0cfa52a1 xattr: add missing consts to function arguments
Add missing consts to xattr function arguments.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Andreas Gruenbacher <agruen@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-29 08:06:06 -07:00
Eric Paris
b19d8eae99 SELinux: selinux/include/security.h whitespace, syntax, and other cleanups
This patch changes selinux/include/security.h to fix whitespace and syntax issues.  Things that
are fixed may include (does not not have to include)

whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-28 09:29:01 +10:00
Eric Paris
a936b79bdf SELinux: objsec.h whitespace, syntax, and other cleanups
This patch changes objsec.h to fix whitespace and syntax issues.  Things that
are fixed may include (does not not have to include)

whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-28 09:29:00 +10:00
Eric Paris
cc03766aaf SELinux: netlabel.h whitespace, syntax, and other cleanups
This patch changes netlabel.h to fix whitespace and syntax issues.  Things that
are fixed may include (does not not have to include)

spaces used instead of tabs

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-28 09:28:59 +10:00
Eric Paris
e392febedb SELinux: avc_ss.h whitespace, syntax, and other cleanups
This patch changes avc_ss.h to fix whitespace and syntax issues.  Things that
are fixed may include (does not not have to include)

whitespace at end of lines
spaces followed by tabs
spaces used instead of tabs
spacing around parenthesis
location of { around structs and else clauses
location of * in pointer declarations
removal of initialization of static data to keep it in the right section
useless {} in if statemetns
useless checking for NULL before kfree
fixing of the indentation depth of switch statements
no assignments in if statements
and any number of other things I forgot to mention

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-28 09:28:58 +10:00
Linus Torvalds
3925e6fc1f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  security: fix up documentation for security_module_enable
  Security: Introduce security= boot parameter
  Audit: Final renamings and cleanup
  SELinux: use new audit hooks, remove redundant exports
  Audit: internally use the new LSM audit hooks
  LSM/Audit: Introduce generic Audit LSM hooks
  SELinux: remove redundant exports
  Netlink: Use generic LSM hook
  Audit: use new LSM hooks instead of SELinux exports
  SELinux: setup new inode/ipc getsecid hooks
  LSM: Introduce inode_getsecid and ipc_getsecid hooks
2008-04-18 18:18:30 -07:00
Linus Torvalds
334d094504 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6.26: (1090 commits)
  [NET]: Fix and allocate less memory for ->priv'less netdevices
  [IPV6]: Fix dangling references on error in fib6_add().
  [NETLABEL]: Fix NULL deref in netlbl_unlabel_staticlist_gen() if ifindex not found
  [PKT_SCHED]: Fix datalen check in tcf_simp_init().
  [INET]: Uninline the __inet_inherit_port call.
  [INET]: Drop the inet_inherit_port() call.
  SCTP: Initialize partial_bytes_acked to 0, when all of the data is acked.
  [netdrvr] forcedeth: internal simplifications; changelog removal
  phylib: factor out get_phy_id from within get_phy_device
  PHY: add BCM5464 support to broadcom PHY driver
  cxgb3: Fix __must_check warning with dev_dbg.
  tc35815: Statistics cleanup
  natsemi: fix MMIO for PPC 44x platforms
  [TIPC]: Cleanup of TIPC reference table code
  [TIPC]: Optimized initialization of TIPC reference table
  [TIPC]: Remove inlining of reference table locking routines
  e1000: convert uint16_t style integers to u16
  ixgb: convert uint16_t style integers to u16
  sb1000.c: make const arrays static
  sb1000.c: stop inlining largish static functions
  ...
2008-04-18 18:02:35 -07:00
Ahmed S. Darwish
04305e4aff Audit: Final renamings and cleanup
Rename the se_str and se_rule audit fields elements to
lsm_str and lsm_rule to avoid confusion.

Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Ahmed S. Darwish <darwish.07@gmail.com>
Acked-by: James Morris <jmorris@namei.org>
2008-04-19 09:59:43 +10:00
James Morris
27cc2a6e57 SELinux: add netport.[ch]
Thank you, git.

Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:17 +10:00
Paul Moore
3e11217263 SELinux: Add network port SID cache
Much like we added a network node cache, this patch adds a network port
cache. The design is taken almost completely from the network node cache
which in turn was taken from the network interface cache.  The basic idea is
to cache entries in a hash table based on protocol/port information.  The
hash function only takes the port number into account since the number of
different protocols in use at any one time is expected to be relatively
small.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:16 +10:00
Eric Paris
832cbd9aa1 SELinux: turn mount options strings into defines
Convert the strings used for mount options into #defines rather than
retyping the string throughout the SELinux code.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:13 +10:00
Eric Paris
64dbf07474 selinux: introduce permissive types
Introduce the concept of a permissive type.  A new ebitmap is introduced to
the policy database which indicates if a given type has the permissive bit
set or not.  This bit is tested for the scontext of any denial.  The bit is
meaningless on types which only appear as the target of a decision and never
the source.  A domain running with a permissive type will be allowed to
perform any action similarly to when the system is globally set permissive.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:11 +10:00
Roland McGrath
0356357c51 selinux: remove ptrace_sid
This changes checks related to ptrace to get rid of the ptrace_sid tracking.
It's good to disentangle the security model from the ptrace implementation
internals.  It's sufficient to check against the SID of the ptracer at the
time a tracee attempts a transition.

Signed-off-by: Roland McGrath <roland@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:10 +10:00
Eric Paris
b0c636b999 SELinux: create new open permission
Adds a new open permission inside SELinux when 'opening' a file.  The idea
is that opening a file and reading/writing to that file are not the same
thing.  Its different if a program had its stdout redirected to /tmp/output
than if the program tried to directly open /tmp/output. This should allow
policy writers to more liberally give read/write permissions across the
policy while still blocking many design and programing flaws SELinux is so
good at catching today.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Reviewed-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:06 +10:00
James Morris
98e9894650 SELinux: remove unused backpointers from security objects
Remove unused backpoiters from security objects.

Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:04 +10:00
Paul Moore
f74af6e816 SELinux: Correct the NetLabel locking for the sk_security_struct
The RCU/spinlock locking approach for the nlbl_state in the sk_security_struct
was almost certainly overkill.  This patch removes both the RCU and spinlock
locking, relying on the existing socket locks to handle the case of multiple
writers.  This change also makes several code reductions possible.

Less locking, less code - it's a Good Thing.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-18 20:26:03 +10:00
David S. Miller
1e42198609 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2008-04-17 23:56:30 -07:00
Paul Moore
03e1ad7b5d LSM: Make the Labeled IPsec hooks more stack friendly
The xfrm_get_policy() and xfrm_add_pol_expire() put some rather large structs
on the stack to work around the LSM API.  This patch attempts to fix that
problem by changing the LSM API to require only the relevant "security"
pointers instead of the entire SPD entry; we do this for all of the
security_xfrm_policy*() functions to keep things consistent.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2008-04-12 19:07:52 -07:00
Stephen Smalley
869ab5147e SELinux: more GFP_NOFS fixups to prevent selinux from re-entering the fs code
More cases where SELinux must not re-enter the fs code. Called from the
d_instantiate security hook.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-04-08 08:30:14 +10:00
Eric Paris
e000752989 LSM/SELinux: Interfaces to allow FS to control mount options
Introduce new LSM interfaces to allow an FS to deal with their own mount
options.  This includes a new string parsing function exported from the
LSM that an FS can use to get a security data blob and a new security
data blob.  This is particularly useful for an FS which uses binary
mount data, like NFS, which does not pass strings into the vfs to be
handled by the loaded LSM.  Also fix a BUG() in both SELinux and SMACK
when dealing with binary mount data.  If the binary mount data is less
than one page the copy_page() in security_sb_copy_data() can cause an
illegal page fault and boom.  Remove all NFSisms from the SELinux code
since they were broken by past NFS changes.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-03-06 08:40:53 +11:00
Jan Blunck
44707fdf59 d_path: Use struct path in struct avc_audit_data
audit_log_d_path() is a d_path() wrapper that is used by the audit code.  To
use a struct path in audit_log_d_path() I need to embed it into struct
avc_audit_data.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Jan Blunck <jblunck@suse.de>
Acked-by: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14 21:17:08 -08:00
Stephen Smalley
b68e418c44 selinux: support 64-bit capabilities
Fix SELinux to handle 64-bit capabilities correctly, and to catch
future extensions of capabilities beyond 64 bits to ensure that SELinux
is properly updated.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-02-11 20:30:02 +11:00
Paul Moore
394c675397 SELinux: Remove security_get_policycaps()
The security_get_policycaps() functions has a couple of bugs in it and it
isn't currently used by any in-tree code, so get rid of it and all of it's
bugginess.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@localhost.localdomain>
2008-02-06 21:40:59 +08:00
Paul Moore
5dbe1eb0cf SELinux: Allow NetLabel to directly cache SIDs
Now that the SELinux NetLabel "base SID" is always the netmsg initial SID we
can do a big optimization - caching the SID and not just the MLS attributes.
This not only saves a lot of per-packet memory allocations and copies but it
has a nice side effect of removing a chunk of code.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:27 +11:00
Paul Moore
d621d35e57 SELinux: Enable dynamic enable/disable of the network access checks
This patch introduces a mechanism for checking when labeled IPsec or SECMARK
are in use by keeping introducing a configuration reference counter for each
subsystem.  In the case of labeled IPsec, whenever a labeled SA or SPD entry
is created the labeled IPsec/XFRM reference count is increased and when the
entry is removed it is decreased.  In the case of SECMARK, when a SECMARK
target is created the reference count is increased and later decreased when the
target is removed.  These reference counters allow SELinux to quickly determine
if either of these subsystems are enabled.

NetLabel already has a similar mechanism which provides the netlbl_enabled()
function.

This patch also renames the selinux_relabel_packet_permission() function to
selinux_secmark_relabel_packet_permission() as the original name and
description were misleading in that they referenced a single packet label which
is not the case.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:26 +11:00
Paul Moore
220deb966e SELinux: Better integration between peer labeling subsystems
Rework the handling of network peer labels so that the different peer labeling
subsystems work better together.  This includes moving both subsystems to a
single "peer" object class which involves not only changes to the permission
checks but an improved method of consolidating multiple packet peer labels.
As part of this work the inbound packet permission check code has been heavily
modified to handle both the old and new behavior in as sane a fashion as
possible.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:25 +11:00
Paul Moore
f67f4f315f SELinux: Add a new peer class and permissions to the Flask definitions
Add additional Flask definitions to support the new "peer" object class and
additional permissions to the netif, node, and packet object classes.  Also,
bring the kernel Flask definitions up to date with the Fedora SELinux policies
by adding the "flow_in" and "flow_out" permissions to the "packet" class.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:24 +11:00
Paul Moore
3bb56b25db SELinux: Add a capabilities bitmap to SELinux policy version 22
Add a new policy capabilities bitmap to SELinux policy version 22.  This bitmap
will enable the security server to query the policy to determine which features
it supports.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:23 +11:00
Paul Moore
224dfbd81e SELinux: Add a network node caching mechanism similar to the sel_netif_*() functions
This patch adds a SELinux IP address/node SID caching mechanism similar to the
sel_netif_*() functions.  The node SID queries in the SELinux hooks files are
also modified to take advantage of this new functionality.  In addition, remove
the address length information from the sk_buff parsing routines as it is
redundant since we already have the address family.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:23 +11:00
Paul Moore
da5645a28a SELinux: Only store the network interface's ifindex
Instead of storing the packet's network interface name store the ifindex.  This
allows us to defer the need to lookup the net_device structure until the audit
record is generated meaning that in the majority of cases we never need to
bother with this at all.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:22 +11:00
Paul Moore
e8bfdb9d0d SELinux: Convert the netif code to use ifindex values
The current SELinux netif code requires the caller have a valid net_device
struct pointer to lookup network interface information.  However, we don't
always have a valid net_device pointer so convert the netif code to use
the ifindex values we always have as part of the sk_buff.  This patch also
removes the default message SID from the network interface record, it is
not being used and therefore is "dead code".

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:21 +11:00
Paul Moore
75e22910cf NetLabel: Add IP address family information to the netlbl_skbuff_getattr() function
In order to do any sort of IP header inspection of incoming packets we need to
know which address family, AF_INET/AF_INET6/etc., it belongs to and since the
sk_buff structure does not store this information we need to pass along the
address family separate from the packet itself.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-30 08:17:20 +11:00
Eric Paris
c9180a57a9 Security: add get, set, and cloning of superblock security information
Adds security_get_sb_mnt_opts, security_set_sb_mnt_opts, and
security_clont_sb_mnt_opts to the LSM and to SELinux.  This will allow
filesystems to directly own and control all of their mount options if they
so choose.  This interface deals only with option identifiers and strings so
it should generic enough for any LSM which may come in the future.

Filesystems which pass text mount data around in the kernel (almost all of
them) need not currently make use of this interface when dealing with
SELinux since it will still parse those strings as it always has.  I assume
future LSM's would do the same.  NFS is the primary FS which does not use
text mount data and thus must make use of this interface.

An LSM would need to implement these functions only if they had mount time
options, such as selinux has context= or fscontext=.  If the LSM has no
mount time options they could simply not implement and let the dummy ops
take care of things.

An LSM other than SELinux would need to define new option numbers in
security.h and any FS which decides to own there own security options would
need to be patched to use this new interface for every possible LSM.  This
is because it was stated to me very clearly that LSM's should not attempt to
understand FS mount data and the burdon to understand security should be in
the FS which owns the options.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen D. Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2008-01-25 11:29:46 +11:00
Eric Paris
3f12070e27 SELinux: policy selectable handling of unknown classes and perms
Allow policy to select, in much the same way as it selects MLS support, how
the kernel should handle access decisions which contain either unknown
classes or unknown permissions in known classes.  The three choices for the
policy flags are

0 - Deny unknown security access. (default)
2 - reject loading policy if it does not contain all definitions
4 - allow unknown security access

The policy's choice is exported through 2 booleans in
selinuxfs.  /selinux/deny_unknown and /selinux/reject_unknown.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-10-17 08:59:33 +10:00
Yuichi Nakamura
788e7dd4c2 SELinux: Improve read/write performance
It reduces the selinux overhead on read/write by only revalidating
permissions in selinux_file_permission if the task or inode labels have
changed or the policy has changed since the open-time check.  A new LSM
hook, security_dentry_open, is added to capture the necessary state at open
time to allow this optimization.

(see http://marc.info/?l=selinux&m=118972995207740&w=2)

Signed-off-by: Yuichi Nakamura<ynakam@hitachisoft.jp>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-10-17 08:59:31 +10:00
Eric Paris
ed03218951 security: Protection for exploiting null dereference using mmap
Add a new security check on mmap operations to see if the user is attempting
to mmap to low area of the address space.  The amount of space protected is
indicated by the new proc tunable /proc/sys/vm/mmap_min_addr and defaults to
0, preserving existing behavior.

This patch uses a new SELinux security class "memprotect."  Policy already
contains a number of allow rules like a_t self:process * (unconfined_t being
one of them) which mean that putting this check in the process class (its
best current fit) would make it useless as all user processes, which we also
want to protect against, would be allowed. By taking the memprotect name of
the new class it will also make it possible for us to move some of the other
memory protect permissions out of 'process' and into the new class next time
we bump the policy version number (which I also think is a good future idea)

Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-07-11 22:52:29 -04:00
Stephen Smalley
2c3c05dbcb SELinux: allow preemption between transition permission checks
In security_get_user_sids, move the transition permission checks
outside of the section holding the policy rdlock, and use the AVC to
perform the checks, calling cond_resched after each one.  These
changes should allow preemption between the individual checks and
enable caching of the results.  It may however increase the overall
time spent in the function in some cases, particularly in the cache
miss case.

The long term fix will be to take much of this logic to userspace by
exporting additional state via selinuxfs, and ultimately deprecating
and eliminating this interface from the kernel.

Tested-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-07-11 22:52:25 -04:00
Christopher J. PeBenito
e47c8fc582 selinux: add selinuxfs structure for object class discovery
The structure is as follows (relative to selinuxfs root):

/class/file/index
/class/file/perms/read
/class/file/perms/write
...

Each class is allocated 33 inodes, 1 for the class index and 32 for
permissions.  Relative to SEL_CLASS_INO_OFFSET, the inode of the index file
DIV 33 is the class number.  The inode of the permission file % 33 is the
index of the permission for that class.

Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-07-11 22:52:20 -04:00
Christopher J. PeBenito
55fcf09b3f selinux: add support for querying object classes and permissions from the running policy
Add support to the SELinux security server for obtaining a list of classes,
and for obtaining a list of permissions for a specified class.

Signed-off-by: Christopher J. PeBenito <cpebenito@tresys.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-07-11 22:52:15 -04:00
James Carter
f0ee2e467f selinux: export initial SID contexts via selinuxfs
Make the initial SID contexts accessible to userspace via selinuxfs.
An initial use of this support will be to make the unlabeled context
available to libselinux for use for invalidated userspace SIDs.

Signed-off-by: James Carter <jwcart2@tycho.nsa.gov>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:36:00 -04:00
Stephen Smalley
a764ae4b07 selinux: remove userland security class and permission definitions
Remove userland security class and permission definitions from the kernel
as the kernel only needs to use and validate its own class and permission
definitions and userland definitions may change.

Signed-off-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:35:58 -04:00
Paul Moore
4f6a993f96 SELinux: move security_skb_extlbl_sid() out of the security server
As suggested, move the security_skb_extlbl_sid() function out of the security
server and into the SELinux hooks file.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:35:56 -04:00
Paul Moore
c60475bf35 SELinux: rename selinux_netlabel.h to netlabel.h
In the beginning I named the file selinux_netlabel.h to avoid potential
namespace colisions.  However, over time I have realized that there are several
other similar cases of multiple header files with the same name so I'm changing
the name to something which better fits with existing naming conventions.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:35:50 -04:00
Paul Moore
5778eabd9c SELinux: extract the NetLabel SELinux support from the security server
Up until this patch the functions which have provided NetLabel support to
SELinux have been integrated into the SELinux security server, which for
various reasons is not really ideal.  This patch makes an effort to extract as
much of the NetLabel support from the security server as possibile and move it
into it's own file within the SELinux directory structure.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2007-04-26 01:35:48 -04:00
Venkat Yekkirala
342a0cff0a [SELINUX]: Fix 2.6.20-rc6 build when no xfrm
This patch is an incremental fix to the flow_cache_genid
patch for selinux that breaks the build of 2.6.20-rc6 when
xfrm is not configured.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-01-26 19:03:48 -08:00
Al Viro
87fcd70d98 [PATCH] selinux endianness annotations
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-12-04 19:32:44 -08:00
James Morris
bb22f58087 Compile fix for "peer secid consolidation for external network labeling"
Use a forward declaration instead of dragging in skbuff.h and
related junk.

Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:24:16 -08:00
Paul Moore
3de4bab5b9 SELinux: peer secid consolidation for external network labeling
Now that labeled IPsec makes use of the peer_sid field in the
sk_security_struct we can remove a lot of the special cases between labeled
IPsec and NetLabel.  In addition, create a new function,
security_skb_extlbl_sid(), which we can use in several places to get the
security context of the packet's external label which allows us to further
simplify the code in a few places.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:24:14 -08:00
Paul Moore
9f2ad66509 NetLabel: SELinux cleanups
This patch does a lot of cleanup in the SELinux NetLabel support code.  A
summary of the changes include:

* Use RCU locking for the NetLabel state variable in the skk_security_struct
  instead of using the inode_security_struct mutex.
* Remove unnecessary parameters in selinux_netlbl_socket_post_create().
* Rename selinux_netlbl_sk_clone_security() to
  selinux_netlbl_sk_security_clone() to better fit the other NetLabel
  sk_security functions.
* Improvements to selinux_netlbl_inode_permission() to help reduce the cost of
  the common case.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:24:13 -08:00
James Morris
2ee92d46c6 [SELinux]: Add support for DCCP
This patch implements SELinux kernel support for DCCP
(http://linux-net.osdl.org/index.php/DCCP), which is similar in
operation to TCP in terms of connected state between peers.

The SELinux support for DCCP is thus modeled on existing handling of
TCP.

A new DCCP socket class is introduced, to allow protocol
differentation.  The permissions for this class inherit all of the
socket permissions, as well as the current TCP permissions (node_bind,
name_bind etc). IPv4 and IPv6 are supported, although labeled
networking is not, at this stage.

Patches for SELinux userspace are at:
http://people.redhat.com/jmorris/selinux/dccp/user/

I've performed some basic testing, and it seems to be working as
expected.  Adding policy support is similar to TCP, the only real
difference being that it's a different protocol.

Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02 21:22:24 -08:00
Venkat Yekkirala
67f83cbf08 SELinux: Fix SA selection semantics
Fix the selection of an SA for an outgoing packet to be at the same
context as the originating socket/flow. This eliminates the SELinux
policy's ability to use/sendto SAs with contexts other than the socket's.

With this patch applied, the SELinux policy will require one or more of the
following for a socket to be able to communicate with/without SAs:

1. To enable a socket to communicate without using labeled-IPSec SAs:

allow socket_t unlabeled_t:association { sendto recvfrom }

2. To enable a socket to communicate with labeled-IPSec SAs:

allow socket_t self:association { sendto };
allow socket_t peer_sa_t:association { recvfrom };

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:21:34 -08:00
Venkat Yekkirala
6b877699c6 SELinux: Return correct context for SO_PEERSEC
Fix SO_PEERSEC for tcp sockets to return the security context of
the peer (as represented by the SA from the peer) as opposed to the
SA used by the local/source socket.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:21:33 -08:00
Venkat Yekkirala
c1a856c964 SELinux: Various xfrm labeling fixes
Since the upstreaming of the mlsxfrm modification a few months back,
testing has resulted in the identification of the following issues/bugs that
are resolved in this patch set.

1. Fix the security context used in the IKE negotiation to be the context
   of the socket as opposed to the context of the SPD rule.

2. Fix SO_PEERSEC for tcp sockets to return the security context of
   the peer as opposed to the source.

3. Fix the selection of an SA for an outgoing packet to be at the same
   context as the originating socket/flow.

The following would be the result of applying this patchset:

- SO_PEERSEC will now correctly return the peer's context.

- IKE deamons will receive the context of the source socket/flow
  as opposed to the SPD rule's context so that the negotiated SA
  will be at the same context as the source socket/flow.

- The SELinux policy will require one or more of the
  following for a socket to be able to communicate with/without SAs:

  1. To enable a socket to communicate without using labeled-IPSec SAs:

     allow socket_t unlabeled_t:association { sendto recvfrom }

  2. To enable a socket to communicate with labeled-IPSec SAs:

     allow socket_t self:association { sendto };
     allow socket_t peer_sa_t:association { recvfrom };

This Patch: Pass correct security context to IKE for use in negotiation

Fix the security context passed to IKE for use in negotiation to be the
context of the socket as opposed to the context of the SPD rule so that
the SA carries the label of the originating socket/flow.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-12-02 21:21:31 -08:00
Chad Sellers
5c45899879 SELinux: export object class and permission definitions
Moves the definition of the 3 structs containing object class and
permission definitions from avc.c to avc_ss.h so that the security
server can access them for validation on policy load. This also adds
a new struct type, defined_classes_perms_t, suitable for allowing the
security server to access these data structures from the avc.

Signed-off-by: Chad Sellers <csellers@tresys.com>
Acked-by:  Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
2006-11-28 12:04:36 -05:00
Paul Moore
f8687afefc [NetLabel]: protect the CIPSOv4 socket option from setsockopt()
This patch makes two changes to protect applications from either removing or
tampering with the CIPSOv4 IP option on a socket.  The first is the requirement
that applications have the CAP_NET_RAW capability to set an IPOPT_CIPSO option
on a socket; this prevents untrusted applications from setting their own
CIPSOv4 security attributes on the packets they send.  The second change is to
SELinux and it prevents applications from setting any IPv4 options when there
is an IPOPT_CIPSO option already present on the socket; this prevents
applications from removing CIPSOv4 security attributes from the packets they
send.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-10-30 15:24:49 -08:00
Venkat Yekkirala
5b368e61c2 IPsec: correct semantics for SELinux policy matching
Currently when an IPSec policy rule doesn't specify a security
context, it is assumed to be "unlabeled" by SELinux, and so
the IPSec policy rule fails to match to a flow that it would
otherwise match to, unless one has explicitly added an SELinux
policy rule allowing the flow to "polmatch" to the "unlabeled"
IPSec policy rules. In the absence of such an explicitly added
SELinux policy rule, the IPSec policy rule fails to match and
so the packet(s) flow in clear text without the otherwise applicable
xfrm(s) applied.

The above SELinux behavior violates the SELinux security notion of
"deny by default" which should actually translate to "encrypt by
default" in the above case.

This was first reported by Evgeniy Polyakov and the way James Morris
was seeing the problem was when connecting via IPsec to a
confined service on an SELinux box (vsftpd), which did not have the
appropriate SELinux policy permissions to send packets via IPsec.

With this patch applied, SELinux "polmatching" of flows Vs. IPSec
policy rules will only come into play when there's a explicit context
specified for the IPSec policy rule (which also means there's corresponding
SELinux policy allowing appropriate domains/flows to polmatch to this context).

Secondly, when a security module is loaded (in this case, SELinux), the
security_xfrm_policy_lookup() hook can return errors other than access denied,
such as -EINVAL.  We were not handling that correctly, and in fact
inverting the return logic and propagating a false "ok" back up to
xfrm_lookup(), which then allowed packets to pass as if they were not
associated with an xfrm policy.

The solution for this is to first ensure that errno values are
correctly propagated all the way back up through the various call chains
from security_xfrm_policy_lookup(), and handled correctly.

Then, flow_cache_lookup() is modified, so that if the policy resolver
fails (typically a permission denied via the security module), the flow
cache entry is killed rather than having a null policy assigned (which
indicates that the packet can pass freely).  This also forces any future
lookups for the same flow to consult the security module (e.g. SELinux)
for current security policy (rather than, say, caching the error on the
flow cache entry).

This patch: Fix the selinux side of things.

This makes sure SELinux polmatching of flow contexts to IPSec policy
rules comes into play only when an explicit context is associated
with the IPSec policy rule.

Also, this no longer defaults the context of a socket policy to
the context of the socket since the "no explicit context" case
is now handled properly.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: James Morris <jmorris@namei.org>
2006-10-11 23:59:37 -07:00
Eric Paris
bc7e982b84 [PATCH] SELinux: convert sbsec semaphore to a mutex
This patch converts the semaphore in the superblock security struct to a
mutex.  No locking changes or other code changes are done.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:53 -07:00
Eric Paris
2397074172 [PATCH] SELinux: change isec semaphore to a mutex
This patch converts the remaining isec->sem into a mutex.  Very similar
locking is provided as before only in the faster smaller mutex rather than a
semaphore.  An out_unlock path is introduced rather than the conditional
unlocking found in the original code.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:53 -07:00
Darrel Goeddel
f3f8771420 [PATCH] selinux: add support for range transitions on object classes
Introduces support for policy version 21.  This version of the binary
kernel policy allows for defining range transitions on security classes
other than the process security class.  As always, backwards compatibility
for older formats is retained.  The security class is read in as specified
when using the new format, while the "process" security class is assumed
when using an older policy format.

Signed-off-by: Darrel Goeddel <dgoeddel@trustedcs.com>
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Stephen Smalley
016b9bdb81 [PATCH] selinux: enable configuration of max policy version
Enable configuration of SELinux maximum supported policy version to support
legacy userland (init) that does not gracefully handle kernels that support
newer policy versions two or more beyond the installed policy, as in FC3
and FC4.

[bunk@stusta.de: improve Kconfig help text]
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Eric Paris <eparis@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:52 -07:00
Paul Moore
7a0e1d6022 [NetLabel]: add some missing #includes to various header files
Add some missing include files to the NetLabel related header files.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:18:39 -07:00
Paul Moore
e448e93130 [NetLabel]: uninline selinux_netlbl_inode_permission()
Uninline the selinux_netlbl_inode_permission() at the request of
Andrew Morton.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:18:38 -07:00
Paul Moore
99f59ed073 [NetLabel]: Correctly initialize the NetLabel fields.
Fix a problem where the NetLabel specific fields of the sk_security_struct
structure were not being initialized early enough in some cases.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:18:34 -07:00
Venkat Yekkirala
7420ed23a4 [NetLabel]: SELinux support
Add NetLabel support to the SELinux LSM and modify the
socket_post_create() LSM hook to return an error code.  The most
significant part of this patch is the addition of NetLabel hooks into
the following SELinux LSM hooks:

 * selinux_file_permission()
 * selinux_socket_sendmsg()
 * selinux_socket_post_create()
 * selinux_socket_sock_rcv_skb()
 * selinux_socket_getpeersec_stream()
 * selinux_socket_getpeersec_dgram()
 * selinux_sock_graft()
 * selinux_inet_conn_request()

The basic reasoning behind this patch is that outgoing packets are
"NetLabel'd" by labeling their socket and the NetLabel security
attributes are checked via the additional hook in
selinux_socket_sock_rcv_skb().  NetLabel itself is only a labeling
mechanism, similar to filesystem extended attributes, it is up to the
SELinux enforcement mechanism to perform the actual access checks.

In addition to the changes outlined above this patch also includes
some changes to the extended bitmap (ebitmap) and multi-level security
(mls) code to import and export SELinux TE/MLS attributes into and out
of NetLabel.

Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:36 -07:00
Venkat Yekkirala
a51c64f1e5 [MLSXFRM]: Fix build with SECURITY_NETWORK_XFRM disabled.
The following patch will fix the build problem (encountered by Andrew
Morton) when SECURITY_NETWORK_XFRM is not enabled.

As compared to git-net-selinux_xfrm_decode_session-build-fix.patch in
-mm, this patch sets the return parameter sid to SECSID_NULL in
selinux_xfrm_decode_session() and handles this value in the caller
selinux_inet_conn_request() appropriately.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:30 -07:00
Venkat Yekkirala
cb969f072b [MLSXFRM]: Default labeling of socket specific IPSec policies
This defaults the label of socket-specific IPSec policies to be the
same as the socket they are set on.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:28 -07:00
Venkat Yekkirala
beb8d13bed [MLSXFRM]: Add flow labeling
This labels the flows that could utilize IPSec xfrms at the points the
flows are defined so that IPSec policy and SAs at the right label can
be used.

The following protos are currently not handled, but they should
continue to be able to use single-labeled IPSec like they currently
do.

ipmr
ip_gre
ipip
igmp
sit
sctp
ip6_tunnel (IPv6 over IPv6 tunnel device)
decnet

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:27 -07:00
Venkat Yekkirala
e0d1caa7b0 [MLSXFRM]: Flow based matching of xfrm policy and state
This implements a seemless mechanism for xfrm policy selection and
state matching based on the flow sid. This also includes the necessary
SELinux enforcement pieces.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:24 -07:00
Venkat Yekkirala
892c141e62 [MLSXFRM]: Add security sid to sock
This adds security for IP sockets at the sock level. Security at the
sock level is needed to enforce the SELinux security policy for
security associations even when a sock is orphaned (such as in the TCP
LAST_ACK state).

This will also be used to enforce SELinux controls over data arriving
at or leaving a child socket while it's still waiting to be accepted.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:22 -07:00
Venkat Yekkirala
08554d6b33 [MLSXFRM]: Define new SELinux service routine
This defines a routine that combines the Type Enforcement portion of
one sid with the MLS portion from the other sid to arrive at a new
sid. This would be used to define a sid for a security association
that is to be negotiated by IKE as well as for determing the sid for
open requests and connection-oriented child sockets.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:21 -07:00
Venkat Yekkirala
51bd39860f [MLSXFRM]: Granular IPSec associations for use in MLS environments
The current approach to labeling Security Associations for SELinux
purposes uses a one-to-one mapping between xfrm policy rules and
security associations.

This doesn't address the needs of real world MLS (Multi-level System,
traditional Bell-LaPadula) environments where a single xfrm policy
rule (pertaining to a range, classified to secret for example) might
need to map to multiple Security Associations (one each for
classified, secret, top secret and all the compartments applicable to
these security levels).

This patch set addresses the above problem by allowing for the mapping
of a single xfrm policy rule to multiple security associations, with
each association used in the security context it is defined for. It
also includes the security context to be used in IKE negotiation in
the acquire messages sent to the IKE daemon so that a unique SA can be
negotiated for each unique security context. A couple of bug fixes are
also included; checks to make sure the SAs used by a packet match
policy (security context-wise) on the inbound and also that the bundle
used for the outbound matches the security context of the flow. This
patch set also makes the use of the SELinux sid in flow cache lookups
seemless by including the sid in the flow key itself. Also, open
requests as well as connection-oriented child sockets are labeled
automatically to be at the same level as the peer to allow for use of
appropriately labeled IPSec associations.

Description of changes:

A "sid" member has been added to the flow cache key resulting in the
sid being available at all needed locations and the flow cache lookups
automatically using the sid. The flow sid is derived from the socket
on the outbound and the SAs (unlabeled where an SA was not used) on
the inbound.

Outbound case:
1. Find policy for the socket.

2. OLD: Find an SA that matches the policy.
 NEW: Find an SA that matches BOTH the policy and the flow/socket.
   This is necessary since not every SA that matches the policy
   can be used for the flow/socket. Consider policy range Secret-TS,
   and SAs each for Secret and TS. We don't want a TS socket to
   use the Secret SA. Hence the additional check for the SA Vs. flow/socket.

3. NEW: When looking thru bundles for a policy, make sure the
        flow/socket can use the bundle. If a bundle is not found,
        create one, calling for IKE if necessary. If using IKE,
        include the security context in the acquire message to the IKE
        daemon.

Inbound case:
1. OLD: Find policy for the socket.
 NEW: Find policy for the incoming packet based on the sid of the
      SA(s) it used or the unlabeled sid if no SAs were
      used. (Consider a case where a socket is "authorized" for two
      policies (unclassified-confidential, secret-top_secret). If the
      packet has come in using a secret SA, we really ought to be
      using the latter policy (secret-top_secret).)

2. OLD: BUG: No check to see if the SAs used by the packet agree with
             the policy sec_ctx-wise.

             (It was indicated in selinux_xfrm_sock_rcv_skb() that
              this was being accomplished by
              (x->id.spi == tmpl->id.spi || !tmpl->id.spi) in xfrm_state_ok,
	      but it turns out tmpl->id.spi
              would normally be zero (unless xfrm policy rules specify one
              at the template level, which they usually don't).
 NEW: The socket is checked for access to the SAs used (based on the
      sid of the SAs) in selinux_xfrm_sock_rcv_skb().

Forward case:
 This would be Step 1 from the Inbound case, followed by Steps 2 and 3
from the Outbound case.

Outstanding items/issues:

- Timewait acknowledgements and such are generated in the
  current/upstream implementation using a NULL socket resulting in the
  any_socket sid (SYSTEM_HIGH) to be used. This problem is not addressed
  by this patch set.

This patch: Add new flask definitions to SELinux

Adds a new avperm "polmatch" to arbitrate flow/state access to a xfrm
policy rule.

Signed-off-by: Venkat Yekkirala <vyekkirala@TrustedCS.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 14:53:20 -07:00
Eric Paris
c312feb293 [PATCH] SELinux: decouple fscontext/context mount options
Remove the conflict between fscontext and context mount options.  If
context= is specified without fscontext it will operate just as before, if
both are specified we will use mount point labeling and all inodes will get
the label specified by context=.  The superblock will be labeled with the
label of fscontext=, thus affecting operations which check the superblock
security context, such as associate permissions.

Signed-off-by: Eric Paris <eparis@parisplace.org>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-07-10 13:24:13 -07:00
Eric Paris
42c3e03ef6 [PATCH] SELinux: Add sockcreate node to procattr API
Below is a patch to add a new /proc/self/attr/sockcreate A process may write a
context into this interface and all subsequent sockets created will be labeled
with that context.  This is the same idea as the fscreate interface where a
process can specify the label of a file about to be created.  At this time one
envisioned user of this will be xinetd.  It will be able to better label
sockets for the actual services.  At this time all sockets take the label of
the creating process, so all xinitd sockets would just be labeled the same.

I tested this by creating a tcp sender and listener.  The sender was able to
write to this new proc file and then create sockets with the specified label.
I am able to be sure the new label was used since the avc denial messages
kicked out by the kernel included both the new security permission
setsockcreate and all the socket denials were for the new label, not the label
of the running process.

Signed-off-by: Eric Paris <eparis@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:26 -07:00
Michael LeMay
4eb582cf1f [PATCH] keys: add a way to store the appropriate context for newly-created keys
Add a /proc/<pid>/attr/keycreate entry that stores the appropriate context for
newly-created keys.  Modify the selinux_key_alloc hook to make use of the new
entry.  Update the flask headers to include a new "setkeycreate" permission
for processes.  Update the flask headers to include a new "create" permission
for keys.  Use the create permission to restrict which SIDs each task can
assign to newly-created keys.  Add a new parameter to the security hook
"security_key_alloc" to indicate whether it is being invoked by the kernel, or
from userspace.  If it is being invoked by the kernel, the security hook
should never fail.  Update the documentation to reflect these changes.

Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-26 09:58:18 -07:00
Michael LeMay
d720024e94 [PATCH] selinux: add hooks for key subsystem
Introduce SELinux hooks to support the access key retention subsystem
within the kernel.  Incorporate new flask headers from a modified version
of the SELinux reference policy, with support for the new security class
representing retained keys.  Extend the "key_alloc" security hook with a
task parameter representing the intended ownership context for the key
being allocated.  Attach security information to root's default keyrings
within the SELinux initialization routine.

Has passed David's testsuite.

Signed-off-by: Michael LeMay <mdlemay@epoch.ncsc.mil>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
Acked-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-22 15:05:55 -07:00
James Morris
4e5ab4cb85 [SECMARK]: Add new packet controls to SELinux
Add new per-packet access controls to SELinux, replacing the old
packet controls.

Packets are labeled with the iptables SECMARK and CONNSECMARK targets,
then security policy for the packets is enforced with these controls.

To allow for a smooth transition to the new controls, the old code is
still present, but not active by default.  To restore previous
behavior, the old controls may be activated at runtime by writing a
'1' to /selinux/compat_net, and also via the kernel boot parameter
selinux_compat_net.  Switching between the network control models
requires the security load_policy permission.  The old controls will
probably eventually be removed and any continued use is discouraged.

With this patch, the new secmark controls for SElinux are disabled by
default, so existing behavior is entirely preserved, and the user is
not affected at all.

It also provides a config option to enable the secmark controls by
default (which can always be overridden at boot and runtime).  It is
also noted in the kconfig help that the user will need updated
userspace if enabling secmark controls for SELinux and that they'll
probably need the SECMARK and CONNMARK targets, and conntrack protocol
helpers, although such decisions are beyond the scope of kernel
configuration.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:30:05 -07:00
James Morris
29a395eac4 [SECMARK]: Add new flask definitions to SELinux
Secmark implements a new scheme for adding security markings to
packets via iptables, as well as changes to SELinux to use these
markings for security policy enforcement.  The rationale for this
scheme is explained and discussed in detail in the original threads:

 http://thread.gmane.org/gmane.linux.network/34927/
 http://thread.gmane.org/gmane.linux.network/35244/

Examples of policy and rulesets, as well as a full archive of patches
for iptables and SELinux userland, may be found at:

http://people.redhat.com/jmorris/selinux/secmark/

The code has been tested with various compilation options and in
several scenarios, including with 'complicated' protocols such as FTP
and also with the new generic conntrack code with IPv6 connection
tracking.

This patch:

Add support for a new object class ('packet'), and associated
permissions ('send', 'recv', 'relabelto').  These are used to enforce
security policy for network packets labeled with SECMARK, and for
adding labeling rules.

Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:53 -07:00
Christopher J. PeBenito
3e3ff15e6d [SELINUX]: add security class for appletalk sockets
Add a security class for appletalk sockets so that they can be
distinguished in SELinux policy.  Please apply.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:51 -07:00
Catherine Zhang
c8c05a8eec [LSM-IPsec]: SELinux Authorize
This patch contains a fix for the previous patch that adds security
contexts to IPsec policies and security associations.  In the previous
patch, no authorization (besides the check for write permissions to
SAD and SPD) is required to delete IPsec policies and security
assocations with security contexts.  Thus a user authorized to change
SAD and SPD can bypass the IPsec policy authorization by simply
deleteing policies with security contexts.  To fix this security hole,
an additional authorization check is added for removing security
policies and security associations with security contexts.

Note that if no security context is supplied on add or present on
policy to be deleted, the SELinux module allows the change
unconditionally.  The hook is called on deletion when no context is
present, which we may want to change.  At present, I left it up to the
module.

LSM changes:

The patch adds two new LSM hooks: xfrm_policy_delete and
xfrm_state_delete.  The new hooks are necessary to authorize deletion
of IPsec policies that have security contexts.  The existing hooks
xfrm_policy_free and xfrm_state_free lack the context to do the
authorization, so I decided to split authorization of deletion and
memory management of security data, as is typical in the LSM
interface.

Use:

The new delete hooks are checked when xfrm_policy or xfrm_state are
deleted by either the xfrm_user interface (xfrm_get_policy,
xfrm_del_sa) or the pfkey interface (pfkey_spddelete, pfkey_delete).

SELinux changes:

The new policy_delete and state_delete functions are added.

Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com>
Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17 21:29:45 -07:00
Stephen Smalley
30d55280b8 [PATCH] selinux: Clear selinux_enabled flag upon runtime disable.
Clear selinux_enabled flag upon runtime disable of SELinux by userspace,
and make sure it is defined even if selinux= boot parameter support is
not enabled in configuration.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Tested-by: Jon Smirl <jonsmirl@gmail.com>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-03 10:08:11 -07:00
Catherine Zhang
e6f507196c [SELINUX]: selinux_socket_getpeer_{stream,dgram} fixup
Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
2006-03-20 22:49:00 -08:00
Catherine Zhang
2c7946a7bf [SECURITY]: TCP/UDP getpeersec
This patch implements an application of the LSM-IPSec networking
controls whereby an application can determine the label of the
security association its TCP or UDP sockets are currently connected to
via getsockopt and the auxiliary data mechanism of recvmsg.

Patch purpose:

This patch enables a security-aware application to retrieve the
security context of an IPSec security association a particular TCP or
UDP socket is using.  The application can then use this security
context to determine the security context for processing on behalf of
the peer at the other end of this connection.  In the case of UDP, the
security context is for each individual packet.  An example
application is the inetd daemon, which could be modified to start
daemons running at security contexts dependent on the remote client.

Patch design approach:

- Design for TCP
The patch enables the SELinux LSM to set the peer security context for
a socket based on the security context of the IPSec security
association.  The application may retrieve this context using
getsockopt.  When called, the kernel determines if the socket is a
connected (TCP_ESTABLISHED) TCP socket and, if so, uses the dst_entry
cache on the socket to retrieve the security associations.  If a
security association has a security context, the context string is
returned, as for UNIX domain sockets.

- Design for UDP
Unlike TCP, UDP is connectionless.  This requires a somewhat different
API to retrieve the peer security context.  With TCP, the peer
security context stays the same throughout the connection, thus it can
be retrieved at any time between when the connection is established
and when it is torn down.  With UDP, each read/write can have
different peer and thus the security context might change every time.
As a result the security context retrieval must be done TOGETHER with
the packet retrieval.

The solution is to build upon the existing Unix domain socket API for
retrieving user credentials.  Linux offers the API for obtaining user
credentials via ancillary messages (i.e., out of band/control messages
that are bundled together with a normal message).

Patch implementation details:

- Implementation for TCP
The security context can be retrieved by applications using getsockopt
with the existing SO_PEERSEC flag.  As an example (ignoring error
checking):

getsockopt(sockfd, SOL_SOCKET, SO_PEERSEC, optbuf, &optlen);
printf("Socket peer context is: %s\n", optbuf);

The SELinux function, selinux_socket_getpeersec, is extended to check
for labeled security associations for connected (TCP_ESTABLISHED ==
sk->sk_state) TCP sockets only.  If so, the socket has a dst_cache of
struct dst_entry values that may refer to security associations.  If
these have security associations with security contexts, the security
context is returned.

getsockopt returns a buffer that contains a security context string or
the buffer is unmodified.

- Implementation for UDP
To retrieve the security context, the application first indicates to
the kernel such desire by setting the IP_PASSSEC option via
getsockopt.  Then the application retrieves the security context using
the auxiliary data mechanism.

An example server application for UDP should look like this:

toggle = 1;
toggle_len = sizeof(toggle);

setsockopt(sockfd, SOL_IP, IP_PASSSEC, &toggle, &toggle_len);
recvmsg(sockfd, &msg_hdr, 0);
if (msg_hdr.msg_controllen > sizeof(struct cmsghdr)) {
    cmsg_hdr = CMSG_FIRSTHDR(&msg_hdr);
    if (cmsg_hdr->cmsg_len <= CMSG_LEN(sizeof(scontext)) &&
        cmsg_hdr->cmsg_level == SOL_IP &&
        cmsg_hdr->cmsg_type == SCM_SECURITY) {
        memcpy(&scontext, CMSG_DATA(cmsg_hdr), sizeof(scontext));
    }
}

ip_setsockopt is enhanced with a new socket option IP_PASSSEC to allow
a server socket to receive security context of the peer.  A new
ancillary message type SCM_SECURITY.

When the packet is received we get the security context from the
sec_path pointer which is contained in the sk_buff, and copy it to the
ancillary message space.  An additional LSM hook,
selinux_socket_getpeersec_udp, is defined to retrieve the security
context from the SELinux space.  The existing function,
selinux_socket_getpeersec does not suit our purpose, because the
security context is copied directly to user space, rather than to
kernel space.

Testing:

We have tested the patch by setting up TCP and UDP connections between
applications on two machines using the IPSec policies that result in
labeled security associations being built.  For TCP, we can then
extract the peer security context using getsockopt on either end.  For
UDP, the receiving end can retrieve the security context using the
auxiliary data mechanism of recvmsg.

Signed-off-by: Catherine Zhang <cxzhang@watson.ibm.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20 22:41:23 -08:00
Stephen Smalley
9ac49d2213 [PATCH] selinux: remove security struct magic number fields and tests
Remove the SELinux security structure magic number fields and tests, along
with some unnecessary tests for NULL security pointers.  These fields and
tests are leftovers from the early attempts to support SELinux as a
loadable module during LSM development.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Acked-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-02-01 08:53:19 -08:00
Trent Jaeger
5f8ac64b15 [LSM-IPSec]: Corrections to LSM-IPSec Nethooks
This patch contains two corrections to the LSM-IPsec Nethooks patches
previously applied.  

(1) free a security context on a failed insert via xfrm_user 
interface in xfrm_add_policy.  Memory leak.

(2) change the authorization of the allocation of a security context
in a xfrm_policy or xfrm_state from both relabelfrom and relabelto 
to setcontext.

Signed-off-by: Trent Jaeger <tjaeger@cse.psu.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-06 13:22:39 -08:00
Trent Jaeger
d28d1e0801 [LSM-IPSec]: Per-packet access control.
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 SELinux LSM to
create, deallocate, and use security contexts for policies
(xfrm_policy) and security associations (xfrm_state) that enable
control of a socket's ability to send and receive packets.

Patch purpose:

The patch is designed to enable the SELinux LSM to implement access
control on individual packets based on the strongly authenticated
IPSec security association.  Such access controls augment the existing
ones in SELinux based on network interface and IP address.  The former
are very coarse-grained, and the latter can be spoofed.  By using
IPSec, the SELinux 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 patch's main function is to authorize a socket's access to a IPSec
policy based on their security contexts.  Since the communication is
implemented by a security association, the patch ensures that the
security association's negotiated and used have the same security
context.  The patch enables allocation and deallocation of such
security contexts for policies and security associations.  It also
enables copying of the security context when policies are cloned.
Lastly, the patch ensures that packets that are sent without using a
IPSec security assocation with a security context are allowed to be
sent in that manner.

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:

The function which authorizes a socket to perform a requested
operation (send/receive) on a IPSec policy (xfrm_policy) is
selinux_xfrm_policy_lookup.  The Netfilter and rcv_skb hooks ensure
that if a IPSec SA with a securit y association has not been used,
then the socket is allowed to send or receive the packet,
respectively.

The patch implements SELinux function for allocating security contexts
when policies (xfrm_policy) are created via the pfkey or xfrm_user
interfaces via selinux_xfrm_policy_alloc.  When a security association
is built, SELinux allocates the security context designated by the
XFRM subsystem which is based on that of the authorized policy via
selinux_xfrm_state_alloc.

When a xfrm_policy is cloned, the security context of that policy, if
any, is copied to the clone via selinux_xfrm_policy_clone.

When a xfrm_policy or xfrm_state is freed, its security context, if
any is also freed at selinux_xfrm_policy_free or
selinux_xfrm_state_free.

Testing:

The SELinux authorization function is tested using ipsec-tools.  We
created policies and security associations with particular security
contexts and added SELinux access control policy entries to verify the
authorization decision.  We also made sure that packets for which no
security context was supplied (which either did or did not use
security associations) were authorized using an unlabelled context.

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>
2006-01-03 13:10:25 -08:00
Stephen Smalley
a74574aafe [PATCH] Remove security_inode_post_create/mkdir/symlink/mknod hooks
This patch removes the inode_post_create/mkdir/mknod/symlink LSM hooks as
they are obsoleted by the new inode_init_security hook that enables atomic
inode security labeling.

If anyone sees any reason to retain these hooks, please speak now.  Also,
is anyone using the post_rename/link hooks; if not, those could also be
removed.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:28 -07:00
Stephen Smalley
5e41ff9e06 [PATCH] security: enable atomic inode security labeling
The following patch set enables atomic security labeling of newly created
inodes by altering the fs code to invoke a new LSM hook to obtain the security
attribute to apply to a newly created inode and to set up the incore inode
security state during the inode creation transaction.  This parallels the
existing processing for setting ACLs on newly created inodes.  Otherwise, it
is possible for new inodes to be accessed by another thread via the dcache
prior to complete security setup (presently handled by the
post_create/mkdir/...  LSM hooks in the VFS) and a newly created inode may be
left unlabeled on the disk in the event of a crash.  SELinux presently works
around the issue by ensuring that the incore inode security label is
initialized to a special SID that is inaccessible to unprivileged processes
(in accordance with policy), thereby preventing inappropriate access but
potentially causing false denials on legitimate accesses.  A simple test
program demonstrates such false denials on SELinux, and the patch solves the
problem.  Similar such false denials have been encountered in real
applications.

This patch defines a new inode_init_security LSM hook to obtain the security
attribute to apply to a newly created inode and to set up the incore inode
security state for it, and adds a corresponding hook function implementation
to SELinux.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-09 13:57:27 -07:00
Stephen Smalley
782ebb992e [PATCH] selinux: Reduce memory use by avtab
This patch improves memory use by SELinux by both reducing the avtab node
size and reducing the number of avtab nodes.  The memory savings are
substantial, e.g.  on a 64-bit system after boot, James Morris reported the
following data for the targeted and strict policies:

            #objs  objsize   kernmem
Targeted:
  Before:  237888       40     9.1MB
  After:    19968       24     468KB

Strict:
  Before:  571680       40   21.81MB
  After:   221052       24    5.06MB

The improvement in memory use comes at a cost in the speed of security
server computations of access vectors, but these computations are only
required on AVC cache misses, and performance measurements by James Morris
using a number of benchmarks have shown that the change does not cause any
significant degradation.

Note that a rebuilt policy via an updated policy toolchain
(libsepol/checkpolicy) is required in order to gain the full benefits of
this patch, although some memory savings benefits are immediately applied
even to older policies (in particular, the reduction in avtab node size).
Sources for the updated toolchain are presently available from the
sourceforge CVS tree (http://sourceforge.net/cvs/?group_id=21266), and
tarballs are available from http://www.flux.utah.edu/~sds.

Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05 00:05:50 -07:00