Commit Graph

186 Commits

Author SHA1 Message Date
David Howells
b072e9bc2f KEYS: Make the key reaper non-reentrant
Make the key reaper non-reentrant by sticking it on the appropriate system work
queue when we queue it.  This will allow it to have global state and drop
locks.  It should probably be non-reentrant already as it may spend a long time
holding the key serial spinlock, and so multiple entrants can spend long
periods of time just sitting there spinning, waiting to get the lock.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:36 +10:00
David Howells
8bc16deabc KEYS: Move the unreferenced key reaper to the keys garbage collector file
Move the unreferenced key reaper function to the keys garbage collector file
as that's a more appropriate place with the dead key link reaper.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:36 +10:00
David Howells
6d528b0822 KEYS: __key_link() should use the RCU deref wrapper for keyring payloads
__key_link() should use the RCU deref wrapper rcu_dereference_locked_keyring()
for accessing keyring payloads rather than calling rcu_dereference_protected()
directly.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:34 +10:00
David Howells
3ecf1b4f34 KEYS: keyctl_get_keyring_ID() should create a session keyring if create flag set
The keyctl call:

	keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1)

should create a session keyring if the process doesn't have one of its own
because the create flag argument is set - rather than subscribing to and
returning the user-session keyring as:

	keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0)

will do.

This can be tested by commenting out pam_keyinit in the /etc/pam.d files and
running the following program a couple of times in a row:

	#include <stdio.h>
	#include <stdlib.h>
	#include <keyutils.h>
	int main(int argc, char *argv[])
	{
		key_serial_t uk, usk, sk, nsk;
		uk  = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0);
		usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0);
		sk  = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0);
		nsk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 1);
		printf("keys: %08x %08x %08x %08x\n", uk, usk, sk, nsk);
		return 0;
	}

Without this patch, I see:

	keys: 3975ddc7 119c0c66 119c0c66 119c0c66
	keys: 3975ddc7 119c0c66 119c0c66 119c0c66

With this patch, I see:

	keys: 2cb4997b 34112878 34112878 17db2ce3
	keys: 2cb4997b 34112878 34112878 39f3c73e

As can be seen, the session keyring starts off the same as the user-session
keyring each time, but with the patch a new session keyring is created when
the create flag is set.

Reported-by: Greg Wettstein <greg@enjellic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Greg Wettstein <greg@enjellic.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:34 +10:00
David Howells
995995378f KEYS: If install_session_keyring() is given a keyring, it should install it
If install_session_keyring() is given a keyring, it should install it rather
than just creating a new one anyway.  This was accidentally broken in:

	commit d84f4f992c
	Author: David Howells <dhowells@redhat.com>
	Date:   Fri Nov 14 10:39:23 2008 +1100
	Subject: CRED: Inaugurate COW credentials

The impact of that commit is that pam_keyinit no longer works correctly if
'force' isn't specified against a login process. This is because:

	keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0)

now always creates a new session keyring and thus the check whether the session
keyring and the user-session keyring are the same is always false.  This leads
pam_keyinit to conclude that a session keyring is installed and it shouldn't be
revoked by pam_keyinit here if 'revoke' is specified.

Any system that specifies 'force' against pam_keyinit in the PAM configuration
files for login methods (login, ssh, su -l, kdm, etc.) is not affected since
that bypasses the broken check and forces the creation of a new session keyring
anyway (for which the revoke flag is not cleared) - and any subsequent call to
pam_keyinit really does have a session keyring already installed, and so the
check works correctly there.

Reverting to the previous behaviour will cause the kernel to subscribe the
process to the user-session keyring as its session keyring if it doesn't have a
session keyring of its own.  pam_keyinit will detect this and install a new
session keyring anyway (and won't clear the revert flag).

This can be tested by commenting out pam_keyinit in the /etc/pam.d files and
running the following program a couple of times in a row:

	#include <stdio.h>
	#include <stdlib.h>
	#include <keyutils.h>
	int main(int argc, char *argv[])
	{
		key_serial_t uk, usk, sk;
		uk = keyctl_get_keyring_ID(KEY_SPEC_USER_KEYRING, 0);
		usk = keyctl_get_keyring_ID(KEY_SPEC_USER_SESSION_KEYRING, 0);
		sk = keyctl_get_keyring_ID(KEY_SPEC_SESSION_KEYRING, 0);
		printf("keys: %08x %08x %08x\n", uk, usk, sk);
		return 0;
	}

Without the patch, I see:

	keys: 3884e281 24c4dfcf 22825f8e
	keys: 3884e281 24c4dfcf 068772be

With the patch, I see:

	keys: 26be9c83 0e755ce0 0e755ce0
	keys: 26be9c83 0e755ce0 0e755ce0

As can be seen, with the patch, the session keyring is the same as the
user-session keyring each time; without the patch a new session keyring is
generated each time.

Reported-by: Greg Wettstein <greg@enjellic.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Tested-by: Greg Wettstein <greg@enjellic.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-08-23 09:57:33 +10:00
Linus Torvalds
95b6886526 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: (54 commits)
  tpm_nsc: Fix bug when loading multiple TPM drivers
  tpm: Move tpm_tis_reenable_interrupts out of CONFIG_PNP block
  tpm: Fix compilation warning when CONFIG_PNP is not defined
  TOMOYO: Update kernel-doc.
  tpm: Fix a typo
  tpm_tis: Probing function for Intel iTPM bug
  tpm_tis: Fix the probing for interrupts
  tpm_tis: Delay ACPI S3 suspend while the TPM is busy
  tpm_tis: Re-enable interrupts upon (S3) resume
  tpm: Fix display of data in pubek sysfs entry
  tpm_tis: Add timeouts sysfs entry
  tpm: Adjust interface timeouts if they are too small
  tpm: Use interface timeouts returned from the TPM
  tpm_tis: Introduce durations sysfs entry
  tpm: Adjust the durations if they are too small
  tpm: Use durations returned from TPM
  TOMOYO: Enable conditional ACL.
  TOMOYO: Allow using argv[]/envp[] of execve() as conditions.
  TOMOYO: Allow using executable's realpath and symlink's target as conditions.
  TOMOYO: Allow using owner/group etc. of file objects as conditions.
  ...

Fix up trivial conflict in security/tomoyo/realpath.c
2011-07-27 19:26:38 -07:00
Jiri Kosina
b7e9c223be Merge branch 'master' into for-next
Sync with Linus' tree to be able to apply pending patches that
are based on newer code already present upstream.
2011-07-11 14:15:55 +02:00
Michal Hocko
d8bf4ca9ca rcu: treewide: Do not use rcu_read_lock_held when calling rcu_dereference_check
Since ca5ecddf (rcu: define __rcu address space modifier for sparse)
rcu_dereference_check use rcu_read_lock_held as a part of condition
automatically so callers do not have to do that as well.

Signed-off-by: Michal Hocko <mhocko@suse.cz>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-07-08 22:21:58 +02:00
James Morris
5b944a71a1 Merge branch 'linus' into next 2011-06-30 18:43:56 +10:00
Roberto Sassu
79a73d1887 encrypted-keys: add ecryptfs format support
The 'encrypted' key type defines its own payload format which contains a
symmetric key randomly generated that cannot be used directly to mount
an eCryptfs filesystem, because it expects an authentication token
structure.

This patch introduces the new format 'ecryptfs' that allows to store an
authentication token structure inside the encrypted key payload containing
a randomly generated symmetric key, as the same for the format 'default'.

More details about the usage of encrypted keys with the eCryptfs
filesystem can be found in the file 'Documentation/keys-ecryptfs.txt'.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Acked-by: Gianluca Ramunno <ramunno@polito.it>
Acked-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27 09:11:17 -04:00
Roberto Sassu
4e561d388f encrypted-keys: add key format support
This patch introduces a new parameter, called 'format', that defines the
format of data stored by encrypted keys. The 'default' format identifies
encrypted keys containing only the symmetric key, while other formats can
be defined to support additional information. The 'format' parameter is
written in the datablob produced by commands 'keyctl print' or
'keyctl pipe' and is integrity protected by the HMAC.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Acked-by: Gianluca Ramunno <ramunno@polito.it>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27 09:10:45 -04:00
Roberto Sassu
7103dff0e5 encrypted-keys: added additional debug messages
Some debug messages have been added in the function datablob_parse() in
order to better identify errors returned when dealing with 'encrypted'
keys.

Changelog from version v4:
- made the debug messages more understandable 

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Acked-by: Gianluca Ramunno <ramunno@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27 09:10:34 -04:00
Roberto Sassu
08fa2aa54e encrypted-keys: fixed valid_master_desc() function description
Valid key type prefixes for the parameter 'key-type' are: 'trusted' and
'user'.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Acked-by: Gianluca Ramunno <ramunno@polito.it>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27 09:08:52 -04:00
Roberto Sassu
f91c2c5cfa encrypted_keys: avoid dumping the master key if the request fails
Do not dump the master key if an error is encountered during the request.

Signed-off-by: Roberto Sassu <roberto.sassu@polito.it>
Acked-by: Gianluca Ramunno <ramunno@polito.it>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
2011-06-27 09:08:39 -04:00
David Howells
b1d7dd80aa KEYS: Fix error handling in construct_key_and_link()
Fix error handling in construct_key_and_link().

If construct_alloc_key() returns an error, it shouldn't pass out through
the normal path as the key_serial() called by the kleave() statement
will oops when it gets an error code in the pointer:

  BUG: unable to handle kernel paging request at ffffffffffffff84
  IP: [<ffffffff8120b401>] request_key_and_link+0x4d7/0x52f
  ..
  Call Trace:
   [<ffffffff8120b52c>] request_key+0x41/0x75
   [<ffffffffa00ed6e8>] cifs_get_spnego_key+0x206/0x226 [cifs]
   [<ffffffffa00eb0c9>] CIFS_SessSetup+0x511/0x1234 [cifs]
   [<ffffffffa00d9799>] cifs_setup_session+0x90/0x1ae [cifs]
   [<ffffffffa00d9c02>] cifs_get_smb_ses+0x34b/0x40f [cifs]
   [<ffffffffa00d9e05>] cifs_mount+0x13f/0x504 [cifs]
   [<ffffffffa00caabb>] cifs_do_mount+0xc4/0x672 [cifs]
   [<ffffffff8113ae8c>] mount_fs+0x69/0x155
   [<ffffffff8114ff0e>] vfs_kern_mount+0x63/0xa0
   [<ffffffff81150be2>] do_kern_mount+0x4d/0xdf
   [<ffffffff81152278>] do_mount+0x63c/0x69f
   [<ffffffff8115255c>] sys_mount+0x88/0xc2
   [<ffffffff814fbdc2>] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-21 18:31:45 -07:00
David Howells
879669961b KEYS/DNS: Fix ____call_usermodehelper() to not lose the session keyring
____call_usermodehelper() now erases any credentials set by the
subprocess_inf::init() function.  The problem is that commit
17f60a7da1 ("capabilites: allow the application of capability limits
to usermode helpers") creates and commits new credentials with
prepare_kernel_cred() after the call to the init() function.  This wipes
all keyrings after umh_keys_init() is called.

The best way to deal with this is to put the init() call just prior to
the commit_creds() call, and pass the cred pointer to init().  That
means that umh_keys_init() and suchlike can modify the credentials
_before_ they are published and potentially in use by the rest of the
system.

This prevents request_key() from working as it is prevented from passing
the session keyring it set up with the authorisation token to
/sbin/request-key, and so the latter can't assume the authority to
instantiate the key.  This causes the in-kernel DNS resolver to fail
with ENOKEY unconditionally.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Eric Paris <eparis@redhat.com>
Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-06-17 09:40:48 -07:00
David Howells
4d67431f80 KEYS: Don't return EAGAIN to keyctl_assume_authority()
Don't return EAGAIN to keyctl_assume_authority() to indicate that a key could
not be found (ENOKEY is only returned if a negative key is found).  Instead
return ENOKEY in both cases.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-06-14 15:03:29 +10:00
Linus Torvalds
e52e713ec3 Merge branch 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs
* 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs:
  Create Documentation/security/, move LSM-, credentials-, and keys-related files from Documentation/   to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/<moved_file>   to Documentation/security/<moved_file>.
2011-05-27 10:25:02 -07:00
Serge E. Hallyn
f7285b5d63 Set cred->user_ns in key_replace_session_keyring
Since this cred was not created with copy_creds(), it needs to get
initialized.  Otherwise use of syscall(__NR_keyctl, KEYCTL_SESSION_TO_PARENT);
can lead to a NULL deref.  Thanks to Robert for finding this.

But introduced by commit 47a150edc2 ("Cache user_ns in struct cred").

Signed-off-by: Serge E. Hallyn <serge.hallyn@canonical.com>
Reported-by: Robert Święcki <robert@swiecki.net>
Cc: David Howells <dhowells@redhat.com>
Cc: stable@kernel.org (2.6.39)
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-05-26 13:49:19 -07:00
James Morris
434d42cfd0 Merge branch 'next' into for-linus 2011-05-24 22:55:24 +10:00
Randy Dunlap
d410fa4ef9 Create Documentation/security/,
move LSM-, credentials-, and keys-related files from Documentation/
  to Documentation/security/,
add Documentation/security/00-INDEX, and
update all occurrences of Documentation/<moved_file>
  to Documentation/security/<moved_file>.
2011-05-19 15:59:38 -07:00
Lai Jiangshan
3acb458c32 security,rcu: convert call_rcu(user_update_rcu_disposal) to kfree_rcu()
The rcu callback user_update_rcu_disposal() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(user_update_rcu_disposal).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
2011-05-07 22:50:54 -07:00
David Howells
4aab1e896a KEYS: Make request_key() and co. return an error for a negative key
Make request_key() and co. return an error for a negative or rejected key.  If
the key was simply negated, then return ENOKEY, otherwise return the error
with which it was rejected.

Without this patch, the following command returns a key number (with the latest
keyutils):

	[root@andromeda ~]# keyctl request2 user debug:foo rejected @s
	586569904

Trying to print the key merely gets you a permission denied error:

	[root@andromeda ~]# keyctl print 586569904
	keyctl_read_alloc: Permission denied

Doing another request_key() call does get you the error, as long as it hasn't
expired yet:

	[root@andromeda ~]# keyctl request user debug:foo
	request_key: Key was rejected by service

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-17 11:59:49 +11:00
David Howells
78b7280cce KEYS: Improve /proc/keys
Improve /proc/keys by:

 (1) Don't attempt to summarise the payload of a negated key.  It won't have
     one.  To this end, a helper function - key_is_instantiated() has been
     added that allows the caller to find out whether the key is positively
     instantiated (as opposed to being uninstantiated or negatively
     instantiated).

 (2) Do show keys that are negative, expired or revoked rather than hiding
     them.  This requires an override flag (no_state_check) to be passed to
     search_my_process_keyrings() and keyring_search_aux() to suppress this
     check.

     Without this, keys that are possessed by the caller, but only grant
     permissions to the caller if possessed are skipped as the possession check
     fails.

     Keys that are visible due to user, group or other checks are visible with
     or without this patch.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-17 11:59:32 +11:00
David Howells
ee009e4a0d KEYS: Add an iovec version of KEYCTL_INSTANTIATE
Add a keyctl op (KEYCTL_INSTANTIATE_IOV) that is like KEYCTL_INSTANTIATE, but
takes an iovec array and concatenates the data in-kernel into one buffer.
Since the KEYCTL_INSTANTIATE copies the data anyway, this isn't too much of a
problem.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-08 11:17:22 +11:00
David Howells
fdd1b94581 KEYS: Add a new keyctl op to reject a key with a specified error code
Add a new keyctl op to reject a key with a specified error code.  This works
much the same as negating a key, and so keyctl_negate_key() is made a special
case of keyctl_reject_key().  The difference is that keyctl_negate_key()
selects ENOKEY as the error to be reported.

Typically the key would be rejected with EKEYEXPIRED, EKEYREVOKED or
EKEYREJECTED, but this is not mandatory.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-08 11:17:18 +11:00
David Howells
b9fffa3877 KEYS: Add a key type op to permit the key description to be vetted
Add a key type operation to permit the key type to vet the description of a new
key that key_alloc() is about to allocate.  The operation may reject the
description if it wishes with an error of its choosing.  If it does this, the
key will not be allocated.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-08 11:17:15 +11:00
David Howells
633e804e89 KEYS: Add an RCU payload dereference macro
Add an RCU payload dereference macro as this seems to be a common piece of code
amongst key types that use RCU referenced payloads.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-03-08 11:17:11 +11:00
David Howells
ceb73c1204 KEYS: Fix __key_link_end() quota fixup on error
Fix __key_link_end()'s attempt to fix up the quota if an error occurs.

There are two erroneous cases: Firstly, we always decrease the quota if
the preallocated replacement keyring needs cleaning up, irrespective of
whether or not we should (we may have replaced a pointer rather than
adding another pointer).

Secondly, we never clean up the quota if we added a pointer without the
keyring storage being extended (we allocate multiple pointers at a time,
even if we're not going to use them all immediately).

We handle this by setting the bottom bit of the preallocation pointer in
__key_link_begin() to indicate that the quota needs fixing up, which is
then passed to __key_link() (which clears the whole thing) and
__key_link_end().

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-26 08:58:20 +10:00
Jesper Juhl
5403110943 trusted keys: Fix a memory leak in trusted_update().
One failure path in security/keys/trusted.c::trusted_update() does
not free 'new_p' while the others do. This patch makes sure we also free
it in the remaining path (if datablob_parse() returns different from
Opt_update).

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-24 10:59:58 +11:00
Mimi Zohar
b970344934 encrypted-keys: rename encrypted_defined files to encrypted
Rename encrypted_defined.c and encrypted_defined.h files to encrypted.c and
encrypted.h, respectively. Based on request from David Howells.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-24 10:27:57 +11:00
Mimi Zohar
4b174b6d28 trusted-keys: rename trusted_defined files to trusted
Rename trusted_defined.c and trusted_defined.h files to trusted.c and
trusted.h, respectively. Based on request from David Howells.

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-24 10:14:22 +11:00
David Howells
973c9f4f49 KEYS: Fix up comments in key management code
Fix up comments in the key management code.  No functional changes.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-21 14:59:30 -08:00
David Howells
a8b17ed019 KEYS: Do some style cleanup in the key management code.
Do a bit of a style clean up in the key management code.  No functional
changes.

Done using:

  perl -p -i -e 's!^/[*]*/\n!!' security/keys/*.c
  perl -p -i -e 's!} /[*] end [a-z0-9_]*[(][)] [*]/\n!}\n!' security/keys/*.c
  sed -i -s -e ": next" -e N -e 's/^\n[}]$/}/' -e t -e P -e 's/^.*\n//' -e "b next" security/keys/*.c

To remove /*****/ lines, remove comments on the closing brace of a
function to name the function and remove blank lines before the closing
brace of a function.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-21 14:59:29 -08:00
Tetsuo Handa
154a96bfcd trusted-keys: avoid scattring va_end()
We can avoid scattering va_end() within the

  va_start();
  for (;;) {

  }
  va_end();

loop, assuming that crypto_shash_init()/crypto_shash_update() return 0 on
success and negative value otherwise.

Make TSS_authhmac()/TSS_checkhmac1()/TSS_checkhmac2() similar to TSS_rawhmac()
by removing "va_end()/goto" from the loop.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-19 09:53:59 +11:00
Tetsuo Handa
0e7491f685 trusted-keys: check for NULL before using it
TSS_rawhmac() checks for data != NULL before using it.
We should do the same thing for TSS_authhmac().

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-19 09:53:56 +11:00
Tetsuo Handa
35576eab39 trusted-keys: another free memory bugfix
TSS_rawhmac() forgot to call va_end()/kfree() when data == NULL and
forgot to call va_end() when crypto_shash_update() < 0.
Fix these bugs by escaping from the loop using "break"
(rather than "return"/"goto") in order to make sure that
va_end()/kfree() are always called.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-19 09:53:53 +11:00
Mimi Zohar
40c1001792 trusted-keys: free memory bugfix
Add missing kfree(td) in tpm_seal() before the return, freeing
td on error paths as well.

Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Safford <safford@watson.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <jmorris@namei.org>
2011-01-14 10:27:46 +11:00
James Morris
d2e7ad1922 Merge branch 'master' into next
Conflicts:
	security/smack/smack_lsm.c

Verified and added fix by Stephen Rothwell <sfr@canb.auug.org.au>
Ok'd by Casey Schaufler <casey@schaufler-ca.com>

Signed-off-by: James Morris <jmorris@namei.org>
2011-01-10 09:46:24 +11:00
David Howells
3fc5e98d8c KEYS: Don't call up_write() if __key_link_begin() returns an error
In construct_alloc_key(), up_write() is called in the error path if
__key_link_begin() fails, but this is incorrect as __key_link_begin() only
returns with the nominated keyring locked if it returns successfully.

Without this patch, you might see the following in dmesg:

	=====================================
	[ BUG: bad unlock balance detected! ]
	-------------------------------------
	mount.cifs/5769 is trying to release lock (&key->sem) at:
	[<ffffffff81201159>] request_key_and_link+0x263/0x3fc
	but there are no more locks to release!

	other info that might help us debug this:
	3 locks held by mount.cifs/5769:
	 #0:  (&type->s_umount_key#41/1){+.+.+.}, at: [<ffffffff81131321>] sget+0x278/0x3e7
	 #1:  (&ret_buf->session_mutex){+.+.+.}, at: [<ffffffffa0258e59>] cifs_get_smb_ses+0x35a/0x443 [cifs]
	 #2:  (root_key_user.cons_lock){+.+.+.}, at: [<ffffffff81201000>] request_key_and_link+0x10a/0x3fc

	stack backtrace:
	Pid: 5769, comm: mount.cifs Not tainted 2.6.37-rc6+ #1
	Call Trace:
	 [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc
	 [<ffffffff81081601>] print_unlock_inbalance_bug+0xca/0xd5
	 [<ffffffff81083248>] lock_release_non_nested+0xc1/0x263
	 [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc
	 [<ffffffff81201159>] ? request_key_and_link+0x263/0x3fc
	 [<ffffffff81083567>] lock_release+0x17d/0x1a4
	 [<ffffffff81073f45>] up_write+0x23/0x3b
	 [<ffffffff81201159>] request_key_and_link+0x263/0x3fc
	 [<ffffffffa026fe9e>] ? cifs_get_spnego_key+0x61/0x21f [cifs]
	 [<ffffffff812013c5>] request_key+0x41/0x74
	 [<ffffffffa027003d>] cifs_get_spnego_key+0x200/0x21f [cifs]
	 [<ffffffffa026e296>] CIFS_SessSetup+0x55d/0x1273 [cifs]
	 [<ffffffffa02589e1>] cifs_setup_session+0x90/0x1ae [cifs]
	 [<ffffffffa0258e7e>] cifs_get_smb_ses+0x37f/0x443 [cifs]
	 [<ffffffffa025a9e3>] cifs_mount+0x1aa1/0x23f3 [cifs]
	 [<ffffffff8111fd94>] ? alloc_debug_processing+0xdb/0x120
	 [<ffffffffa027002c>] ? cifs_get_spnego_key+0x1ef/0x21f [cifs]
	 [<ffffffffa024cc71>] cifs_do_mount+0x165/0x2b3 [cifs]
	 [<ffffffff81130e72>] vfs_kern_mount+0xaf/0x1dc
	 [<ffffffff81131007>] do_kern_mount+0x4d/0xef
	 [<ffffffff811483b9>] do_mount+0x6f4/0x733
	 [<ffffffff8114861f>] sys_mount+0x88/0xc2
	 [<ffffffff8100ac42>] system_call_fastpath+0x16/0x1b

Reported-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-and-Tested-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-12-23 15:31:48 -08:00
Mimi Zohar
3b1826cebe encrypted-keys: style and other cleanup
Cleanup based on David Howells suggestions:
- use static const char arrays instead of #define
- rename init_sdesc to alloc_sdesc
- convert 'unsigned int' definitions to 'size_t'
- revert remaining 'const unsigned int' definitions to 'unsigned int'

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-12-15 12:14:34 +05:30
Mimi Zohar
1f35065a9e encrypted-keys: verify datablob size before converting to binary
Verify the hex ascii datablob length is correct before converting the IV,
encrypted data, and HMAC to binary.

Reported-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-12-15 12:14:32 +05:30
Mimi Zohar
1bdbb4024c trusted-keys: kzalloc and other cleanup
Cleanup based on David Howells suggestions:
- replace kzalloc, where possible, with kmalloc
- revert 'const unsigned int' definitions to 'unsigned int'

Signed-off-by: David Safford <safford@watson.ibm.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-12-15 12:14:27 +05:30
Mimi Zohar
bc5e0af0b3 trusted-keys: additional TSS return code and other error handling
Previously not all TSS return codes were tested, as they were all eventually
caught by the TPM. Now all returns are tested and handled immediately.

This patch also fixes memory leaks in error and non-error paths.

Signed-off-by: David Safford <safford@watson.ibm.com>
Acked-by: Mimi Zohar <zohar@us.ibm.com>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Serge E. Hallyn <serge@hallyn.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-12-15 12:14:25 +05:30
Mimi Zohar
93ae86e759 keys: add missing include file for trusted and encrypted keys
This patch fixes the linux-next powerpc build errors as reported by
Stephen Rothwell.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Tested-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-11-30 09:20:27 +11:00
Mimi Zohar
7e70cb4978 keys: add new key-type encrypted
Define a new kernel key-type called 'encrypted'. Encrypted keys are kernel
generated random numbers, which are encrypted/decrypted with a 'trusted'
symmetric key. Encrypted keys are created/encrypted/decrypted in the kernel.
Userspace only ever sees/stores encrypted blobs.

Changelog:
- bug fix: replaced master-key rcu based locking with semaphore
  (reported by David Howells)
- Removed memset of crypto_shash_digest() digest output
- Replaced verification of 'key-type:key-desc' using strcspn(), with
  one based on string constants.
- Moved documentation to Documentation/keys-trusted-encrypted.txt
- Replace hash with shash (based on comments by David Howells)
- Make lengths/counts size_t where possible (based on comments by David Howells)
  Could not convert most lengths, as crypto expects 'unsigned int'
  (size_t: on 32 bit is defined as unsigned int, but on 64 bit is unsigned long)
- Add 'const' where possible (based on comments by David Howells)
- allocate derived_buf dynamically to support arbitrary length master key
  (fixed by Roberto Sassu)
- wait until late_initcall for crypto libraries to be registered
- cleanup security/Kconfig
- Add missing 'update' keyword (reported/fixed by Roberto Sassu)
- Free epayload on failure to create key (reported/fixed by Roberto Sassu)
- Increase the data size limit (requested by Roberto Sassu)
- Crypto return codes are always 0 on success and negative on failure,
  remove unnecessary tests.
- Replaced kzalloc() with kmalloc()

Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: David Safford <safford@watson.ibm.com>
Reviewed-by: Roberto Sassu <roberto.sassu@polito.it>
Signed-off-by: James Morris <jmorris@namei.org>
2010-11-29 08:55:29 +11:00
Mimi Zohar
d00a1c72f7 keys: add new trusted key-type
Define a new kernel key-type called 'trusted'.  Trusted keys are random
number symmetric keys, generated and RSA-sealed by the TPM.  The TPM
only unseals the keys, if the boot PCRs and other criteria match.
Userspace can only ever see encrypted blobs.

Based on suggestions by Jason Gunthorpe, several new options have been
added to support additional usages.

The new options are:
migratable=  designates that the key may/may not ever be updated
             (resealed under a new key, new pcrinfo or new auth.)

pcrlock=n    extends the designated PCR 'n' with a random value,
             so that a key sealed to that PCR may not be unsealed
             again until after a reboot.

keyhandle=   specifies the sealing/unsealing key handle.

keyauth=     specifies the sealing/unsealing key auth.

blobauth=    specifies the sealed data auth.

Implementation of a kernel reserved locality for trusted keys will be
investigated for a possible future extension.

Changelog:
- Updated and added examples to Documentation/keys-trusted-encrypted.txt
- Moved generic TPM constants to include/linux/tpm_command.h
  (David Howell's suggestion.)
- trusted_defined.c: replaced kzalloc with kmalloc, added pcrlock failure
  error handling, added const qualifiers where appropriate.
- moved to late_initcall
- updated from hash to shash (suggestion by David Howells)
- reduced worst stack usage (tpm_seal) from 530 to 312 bytes
- moved documentation to Documentation directory (suggestion by David Howells)
- all the other code cleanups suggested by David Howells
- Add pcrlock CAP_SYS_ADMIN dependency (based on comment by Jason Gunthorpe)
- New options: migratable, pcrlock, keyhandle, keyauth, blobauth (based on
  discussions with Jason Gunthorpe)
- Free payload on failure to create key(reported/fixed by Roberto Sassu)
- Updated Kconfig and other descriptions (based on Serge Hallyn's suggestion)
- Replaced kzalloc() with kmalloc() (reported by Serge Hallyn)

Signed-off-by: David Safford <safford@watson.ibm.com>
Signed-off-by: Mimi Zohar <zohar@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>
2010-11-29 08:55:25 +11:00
Andi Kleen
27d6379894 Fix install_process_keyring error handling
Fix an incorrect error check that returns 1 for error instead of the
expected error code.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-10-28 09:02:15 -07:00
David Howells
3d96406c7d KEYS: Fix bug in keyctl_session_to_parent() if parent has no session keyring
Fix a bug in keyctl_session_to_parent() whereby it tries to check the ownership
of the parent process's session keyring whether or not the parent has a session
keyring [CVE-2010-2960].

This results in the following oops:

  BUG: unable to handle kernel NULL pointer dereference at 00000000000000a0
  IP: [<ffffffff811ae4dd>] keyctl_session_to_parent+0x251/0x443
  ...
  Call Trace:
   [<ffffffff811ae2f3>] ? keyctl_session_to_parent+0x67/0x443
   [<ffffffff8109d286>] ? __do_fault+0x24b/0x3d0
   [<ffffffff811af98c>] sys_keyctl+0xb4/0xb8
   [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b

if the parent process has no session keyring.

If the system is using pam_keyinit then it mostly protected against this as all
processes derived from a login will have inherited the session keyring created
by pam_keyinit during the log in procedure.

To test this, pam_keyinit calls need to be commented out in /etc/pam.d/.

Reported-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Tavis Ormandy <taviso@cmpxchg8b.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10 07:30:00 -07:00
David Howells
9d1ac65a96 KEYS: Fix RCU no-lock warning in keyctl_session_to_parent()
There's an protected access to the parent process's credentials in the middle
of keyctl_session_to_parent().  This results in the following RCU warning:

  ===================================================
  [ INFO: suspicious rcu_dereference_check() usage. ]
  ---------------------------------------------------
  security/keys/keyctl.c:1291 invoked rcu_dereference_check() without protection!

  other info that might help us debug this:

  rcu_scheduler_active = 1, debug_locks = 0
  1 lock held by keyctl-session-/2137:
   #0:  (tasklist_lock){.+.+..}, at: [<ffffffff811ae2ec>] keyctl_session_to_parent+0x60/0x236

  stack backtrace:
  Pid: 2137, comm: keyctl-session- Not tainted 2.6.36-rc2-cachefs+ #1
  Call Trace:
   [<ffffffff8105606a>] lockdep_rcu_dereference+0xaa/0xb3
   [<ffffffff811ae379>] keyctl_session_to_parent+0xed/0x236
   [<ffffffff811af77e>] sys_keyctl+0xb4/0xb6
   [<ffffffff81001eab>] system_call_fastpath+0x16/0x1b

The code should take the RCU read lock to make sure the parents credentials
don't go away, even though it's holding a spinlock and has IRQ disabled.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-09-10 07:30:00 -07:00