linux-toradex.git/Documentation/keys.txt, branch v2.6.19-rc2

Documentation: remove duplicated words

2006-10-03T20:57:56+00:00

Remove many duplicated words under Documentation/ and do other small
cleanups.

Examples:
        "and and" --> "and"
        "in in" --> "in"
        "the the" --> "the"
        "the the" --> "to the"
        ...

Signed-off-by: Paolo Ornati 
Signed-off-by: Adrian Bunk

Fix typos in Documentation/: 'H'-'M'

2006-10-03T20:50:39+00:00

This patch fixes typos in various Documentation txts. The patch addresses
some words starting with the letters 'H'-'M'.

Signed-off-by: Matt LaPlante 
Acked-by: Randy Dunlap 
Signed-off-by: Adrian Bunk

Fix some typos in Documentation/: 'A'

2006-10-03T20:45:33+00:00

This patch fixes typos in various Documentation txts.
This patch addresses some words starting with the letter 'A'.

Signed-off-by: Matt LaPlante 
Acked-by: Randy Dunlap 
Acked-by: Alan Cox 
Signed-off-by: Adrian Bunk

[PATCH] Keys: Allow in-kernel key requestor to pass auxiliary data to upcaller

2006-06-29T17:26:20+00:00

The proposed NFS key type uses its own method of passing key requests to
userspace (upcalling) rather than invoking /sbin/request-key.  This is
because the responsible userspace daemon should already be running and will
be contacted through rpc_pipefs.

This patch permits the NFS filesystem to pass auxiliary data to the upcall
operation (struct key_type::request_key) so that the upcaller can use a
pre-existing communications channel more easily.

Signed-off-by: David Howells 
Acked-By: Kevin Coffman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] keys: add a way to store the appropriate context for newly-created keys

2006-06-26T16:58:18+00:00

Add a /proc//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 
Signed-off-by: James Morris 
Signed-off-by: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] keys: restrict contents of /proc/keys to Viewable keys

2006-06-26T16:58:18+00:00

Restrict /proc/keys such that only those keys to which the current task is
granted View permission are presented.

The documentation is also updated to reflect these changes.

Signed-off-by: Michael LeMay 
Signed-off-by: James Morris 
Signed-off-by: David Howells 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] Keys: Fix race between two instantiators of a key

2006-06-22T22:05:56+00:00

Add a revocation notification method to the key type and calls it whilst
the key's semaphore is still write-locked after setting the revocation
flag.

The patch then uses this to maintain a reference on the task_struct of the
process that calls request_key() for as long as the authorisation key
remains unrevoked.

This fixes a potential race between two processes both of which have
assumed the authority to instantiate a key (one may have forked the other
for example).  The problem is that there's no locking around the check for
revocation of the auth key and the use of the task_struct it points to, nor
does the auth key keep a reference on the task_struct.

Access to the "context" pointer in the auth key must thenceforth be done
with the auth key semaphore held.  The revocation method is called with the
target key semaphore held write-locked and the search of the context
process's keyrings is done with the auth key semaphore read-locked.

The check for the revocation state of the auth key just prior to searching
it is done after the auth key is read-locked for the search.  This ensures
that the auth key can't be revoked between the check and the search.

The revocation notification method is added so that the context task_struct
can be released as soon as instantiation happens rather than waiting for
the auth key to be destroyed, thus avoiding the unnecessary pinning of the
requesting process.

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

[PATCH] selinux: add hooks for key subsystem

2006-06-22T22:05:55+00:00

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 
Signed-off-by: David Howells 
Signed-off-by: James Morris 
Acked-by: Chris Wright 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] keys: Permit running process to instantiate keys

2006-01-09T04:13:53+00:00

Make it possible for a running process (such as gssapid) to be able to
instantiate a key, as was requested by Trond Myklebust for NFS4.

The patch makes the following changes:

 (1) A new, optional key type method has been added. This permits a key type
     to intercept requests at the point /sbin/request-key is about to be
     spawned and do something else with them - passing them over the
     rpc_pipefs files or netlink sockets for instance.

     The uninstantiated key, the authorisation key and the intended operation
     name are passed to the method.

 (2) The callout_info is no longer passed as an argument to /sbin/request-key
     to prevent unauthorised viewing of this data using ps or by looking in
     /proc/pid/cmdline.

     This means that the old /sbin/request-key program will not work with the
     patched kernel as it will expect to see an extra argument that is no
     longer there.

     A revised keyutils package will be made available tomorrow.

 (3) The callout_info is now attached to the authorisation key. Reading this
     key will retrieve the information.

 (4) A new field has been added to the task_struct. This holds the
     authorisation key currently active for a thread. Searches now look here
     for the caller's set of keys rather than looking for an auth key in the
     lowest level of the session keyring.

     This permits a thread to be servicing multiple requests at once and to
     switch between them. Note that this is per-thread, not per-process, and
     so is usable in multithreaded programs.

     The setting of this field is inherited across fork and exec.

 (5) A new keyctl function (KEYCTL_ASSUME_AUTHORITY) has been added that
     permits a thread to assume the authority to deal with an uninstantiated
     key. Assumption is only permitted if the authorisation key associated
     with the uninstantiated key is somewhere in the thread's keyrings.

     This function can also clear the assumption.

 (6) A new magic key specifier has been added to refer to the currently
     assumed authorisation key (KEY_SPEC_REQKEY_AUTH_KEY).

 (7) Instantiation will only proceed if the appropriate authorisation key is
     assumed first. The assumed authorisation key is discarded if
     instantiation is successful.

 (8) key_validate() is moved from the file of request_key functions to the
     file of permissions functions.

 (9) The documentation is updated.

From: 

    Build fix.

Signed-off-by: David Howells 
Cc: Trond Myklebust 
Cc: Alexander Zangerl 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] keys: Discard duplicate keys from a keyring on link

2006-01-09T04:13:53+00:00

Cause any links within a keyring to keys that match a key to be linked into
that keyring to be discarded as a link to the new key is added.  The match is
contingent on the type and description strings being the same.

This permits requests, adds and searches to displace negative, expired,
revoked and dead keys easily.  After some discussion it was concluded that
duplicate valid keys should probably be discarded also as they would otherwise
hide the new key.

Since request_key() is intended to be the primary method by which keys are
added to a keyring, duplicate valid keys wouldn't be an issue there as that
function would return an existing match in preference to creating a new key.

Signed-off-by: David Howells 
Cc: Trond Myklebust 
Cc: Alexander Zangerl 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds