litmus-rt.git/security/keys, branch v2.6.27-rc3

keys: remove unused key_alloc_sem

2008-06-06T18:29:11+00:00

This semaphore doesn't appear to be used, so remove it.

Signed-off-by: Daniel Walker 
Cc: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: explicitly include required slab.h header file.

2008-04-29T15:06:17+00:00

Since these two source files invoke kmalloc(), they should explicitly
include .

Signed-off-by: Robert P. J. Day 
Cc: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: make the keyring quotas controllable through /proc/sys

2008-04-29T15:06:17+00:00

Make the keyring quotas controllable through /proc/sys files:

 (*) /proc/sys/kernel/keys/root_maxkeys
     /proc/sys/kernel/keys/root_maxbytes

     Maximum number of keys that root may have and the maximum total number of
     bytes of data that root may have stored in those keys.

 (*) /proc/sys/kernel/keys/maxkeys
     /proc/sys/kernel/keys/maxbytes

     Maximum number of keys that each non-root user may have and the maximum
     total number of bytes of data that each of those users may have stored in
     their keys.

Also increase the quotas as a number of people have been complaining that it's
not big enough.  I'm not sure that it's big enough now either, but on the
other hand, it can now be set in /etc/sysctl.conf.

Signed-off-by: David Howells 
Cc: 
Cc: 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: don't generate user and user session keyrings unless they're accessed

2008-04-29T15:06:17+00:00

Don't generate the per-UID user and user session keyrings unless they're
explicitly accessed.  This solves a problem during a login process whereby
set*uid() is called before the SELinux PAM module, resulting in the per-UID
keyrings having the wrong security labels.

This also cures the problem of multiple per-UID keyrings sometimes appearing
due to PAM modules (including pam_keyinit) setuiding and causing user_structs
to come into and go out of existence whilst the session keyring pins the user
keyring.  This is achieved by first searching for extant per-UID keyrings
before inventing new ones.

The serial bound argument is also dropped from find_keyring_by_name() as it's
not currently made use of (setting it to 0 disables the feature).

Signed-off-by: David Howells 
Cc: 
Cc: 
Cc: 
Cc: Stephen Smalley 
Cc: James Morris 
Cc: Chris Wright 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: allow clients to set key perms in key_create_or_update()

2008-04-29T15:06:16+00:00

The key_create_or_update() function provided by the keyring code has a default
set of permissions that are always applied to the key when created.  This
might not be desirable to all clients.

Here's a patch that adds a "perm" parameter to the function to address this,
which can be set to KEY_PERM_UNDEF to revert to the current behaviour.

Signed-off-by: Arun Raghavan 
Signed-off-by: David Howells 
Cc: Satyam Sharma 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: switch to proc_create()

2008-04-29T15:06:16+00:00

Signed-off-by: Alexey Dobriyan 
Cc: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: add keyctl function to get a security label

2008-04-29T15:06:16+00:00

Add a keyctl() function to get the security label of a key.

The following is added to Documentation/keys.txt:

 (*) Get the LSM security context attached to a key.

	long keyctl(KEYCTL_GET_SECURITY, key_serial_t key, char *buffer,
		    size_t buflen)

     This function returns a string that represents the LSM security context
     attached to a key in the buffer provided.

     Unless there's an error, it always returns the amount of data it could
     produce, even if that's too big for the buffer, but it won't copy more
     than requested to userspace. If the buffer pointer is NULL then no copy
     will take place.

     A NUL character is included at the end of the string if the buffer is
     sufficiently big.  This is included in the returned count.  If no LSM is
     in force then an empty string will be returned.

     A process must have view permission on the key for this function to be
     successful.

[akpm@linux-foundation.org: declare keyctl_get_security()]
Signed-off-by: David Howells 
Acked-by: Stephen Smalley 
Cc: Paul Moore 
Cc: Chris Wright 
Cc: James Morris 
Cc: Kevin Coffman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: allow the callout data to be passed as a blob rather than a string

2008-04-29T15:06:16+00:00

Allow the callout data to be passed as a blob rather than a string for
internal kernel services that call any request_key_*() interface other than
request_key().  request_key() itself still takes a NUL-terminated string.

The functions that change are:

	request_key_with_auxdata()
	request_key_async()
	request_key_async_with_auxdata()

Signed-off-by: David Howells 
Cc: Paul Moore 
Cc: Chris Wright 
Cc: Stephen Smalley 
Cc: James Morris 
Cc: Kevin Coffman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: check starting keyring as part of search

2008-04-29T15:06:16+00:00

Check the starting keyring as part of the search to (a) see if that is what
we're searching for, and (b) to check it is still valid for searching.

The scenario: User in process A does things that cause things to be created in
its process session keyring.  The user then does an su to another user and
starts a new process, B.  The two processes now share the same process session
keyring.

Process B does an NFS access which results in an upcall to gssd.  When gssd
attempts to instantiate the context key (to be linked into the process session
keyring), it is denied access even though it has an authorization key.

The order of calls is:

   keyctl_instantiate_key()
      lookup_user_key()				    (the default: case)
         search_process_keyrings(current)
	    search_process_keyrings(rka->context)   (recursive call)
	       keyring_search_aux()

keyring_search_aux() verifies the keys and keyrings underneath the top-level
keyring it is given, but that top-level keyring is neither fully validated nor
checked to see if it is the thing being searched for.

This patch changes keyring_search_aux() to:
1) do more validation on the top keyring it is given and
2) check whether that top-level keyring is the thing being searched for

Signed-off-by: Kevin Coffman 
Signed-off-by: David Howells 
Cc: Paul Moore 
Cc: Chris Wright 
Cc: Stephen Smalley 
Cc: James Morris 
Cc: Kevin Coffman 
Cc: Trond Myklebust 
Cc: "J. Bruce Fields" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

keys: increase the payload size when instantiating a key

2008-04-29T15:06:16+00:00

Increase the size of a payload that can be used to instantiate a key in
add_key() and keyctl_instantiate_key().  This permits huge CIFS SPNEGO blobs
to be passed around.  The limit is raised to 1MB.  If kmalloc() can't allocate
a buffer of sufficient size, vmalloc() will be tried instead.

Signed-off-by: David Howells 
Cc: Paul Moore 
Cc: Chris Wright 
Cc: Stephen Smalley 
Cc: James Morris 
Cc: Kevin Coffman 
Cc: Steven French 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds