linux-toradex.git/security/keys/user_defined.c, branch v3.10.2

KEYS: Add payload preparsing opportunity prior to key instantiate or update

2012-10-08T03:19:48+00:00

Give the key type the opportunity to preparse the payload prior to the
instantiation and update routines being called.  This is done with the
provision of two new key type operations:

	int (*preparse)(struct key_preparsed_payload *prep);
	void (*free_preparse)(struct key_preparsed_payload *prep);

If the first operation is present, then it is called before key creation (in
the add/update case) or before the key semaphore is taken (in the update and
instantiate cases).  The second operation is called to clean up if the first
was called.

preparse() is given the opportunity to fill in the following structure:

	struct key_preparsed_payload {
		char		*description;
		void		*type_data[2];
		void		*payload;
		const void	*data;
		size_t		datalen;
		size_t		quotalen;
	};

Before the preparser is called, the first three fields will have been cleared,
the payload pointer and size will be stored in data and datalen and the default
quota size from the key_type struct will be stored into quotalen.

The preparser may parse the payload in any way it likes and may store data in
the type_data[] and payload fields for use by the instantiate() and update()
ops.

The preparser may also propose a description for the key by attaching it as a
string to the description field.  This can be used by passing a NULL or ""
description to the add_key() system call or the key_create_or_update()
function.  This cannot work with request_key() as that required the description
to tell the upcall about the key to be created.

This, for example permits keys that store PGP public keys to generate their own
name from the user ID and public key fingerprint in the key.

The instantiate() and update() operations are then modified to look like this:

	int (*instantiate)(struct key *key, struct key_preparsed_payload *prep);
	int (*update)(struct key *key, struct key_preparsed_payload *prep);

and the new payload data is passed in *prep, whether or not it was preparsed.

Signed-off-by: David Howells 
Signed-off-by: Rusty Russell

Merge git://git.samba.org/sfrench/cifs-2.6

2012-01-23T16:59:49+00:00

* git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Rename *UCS* functions to *UTF16*
  [CIFS] ACL and FSCACHE support no longer EXPERIMENTAL
  [CIFS] Fix build break with multiuser patch when LANMAN disabled
  cifs: warn about impending deprecation of legacy MultiuserMount code
  cifs: fetch credentials out of keyring for non-krb5 auth multiuser mounts
  cifs: sanitize username handling
  keys: add a "logon" key type
  cifs: lower default wsize when unix extensions are not used
  cifs: better instrumentation for coalesce_t2
  cifs: integer overflow in parse_dacl()
  cifs: Fix sparse warning when calling cifs_strtoUCS
  CIFS: Add descriptions to the brlock cache functions

keys: fix user_defined key sparse messages

2012-01-19T05:16:29+00:00

Replace the rcu_assign_pointer() calls with rcu_assign_keypointer().

Signed-off-by: Mimi Zohar 
Signed-off-by: David Howells 
Signed-off-by: James Morris

keys: add a "logon" key type

2012-01-18T04:39:40+00:00

For CIFS, we want to be able to store NTLM credentials (aka username
and password) in the keyring. We do not, however want to allow users
to fetch those keys back out of the keyring since that would be a
security risk.

Unfortunately, due to the nuances of key permission bits, it's not
possible to do this. We need to grant search permissions so the kernel
can find these keys, but that also implies permissions to read the
payload.

Resolve this by adding a new key_type. This key type is essentially
the same as key_type_user, but does not define a .read op. This
prevents the payload from ever being visible from userspace. This
key type also vets the description to ensure that it's "qualified"
by checking to ensure that it has a ':' in it that is preceded by
other characters.

Acked-by: David Howells 
Signed-off-by: Jeff Layton 
Signed-off-by: Steve French

KEYS: Fix a NULL pointer deref in the user-defined key type

2011-11-16T00:32:38+00:00

Fix a NULL pointer deref in the user-defined key type whereby updating a
negative key into a fully instantiated key will cause an oops to occur
when the code attempts to free the non-existent old payload.

This results in an oops that looks something like the following:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
  IP: [] __call_rcu+0x11/0x13e
  PGD 3391d067 PUD 3894a067 PMD 0
  Oops: 0002 [#1] SMP
  CPU 1
  Pid: 4354, comm: keyctl Not tainted 3.1.0-fsdevel+ #1140                  /DG965RY
  RIP: 0010:[]  [] __call_rcu+0x11/0x13e
  RSP: 0018:ffff88003d591df8  EFLAGS: 00010246
  RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000006e
  RDX: ffffffff8161d0c0 RSI: 0000000000000000 RDI: 0000000000000000
  RBP: ffff88003d591e18 R08: 0000000000000000 R09: ffffffff8152fa6c
  R10: 0000000000000000 R11: 0000000000000300 R12: ffff88003b8f9538
  R13: ffffffff8161d0c0 R14: ffff88003b8f9d50 R15: ffff88003c69f908
  FS:  00007f97eb18c720(0000) GS:ffff88003bd00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000008 CR3: 000000003d47a000 CR4: 00000000000006e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Process keyctl (pid: 4354, threadinfo ffff88003d590000, task ffff88003c78a040)
  Stack:
   ffff88003e0ffde0 ffff88003b8f9538 0000000000000001 ffff88003b8f9d50
   ffff88003d591e28 ffffffff810860f0 ffff88003d591e68 ffffffff8117bfea
   ffff88003d591e68 ffffffff00000000 ffff88003e0ffde1 ffff88003e0ffde0
  Call Trace:
   [] call_rcu_sched+0x10/0x12
   [] user_update+0x8d/0xa2
   [] key_create_or_update+0x236/0x270
   [] sys_add_key+0x123/0x17e
   [] system_call_fastpath+0x16/0x1b

Signed-off-by: David Howells 
Acked-by: Jeff Layton 
Acked-by: Neil Horman 
Acked-by: Steve Dickson 
Acked-by: James Morris 
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds

Merge branch 'next' into for-linus

2011-05-24T12:55:24+00:00

security,rcu: convert call_rcu(user_update_rcu_disposal) to kfree_rcu()

2011-05-08T05:50:54+00:00

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 
Signed-off-by: Paul E. McKenney 
Acked-by: David Howells 
Reviewed-by: Josh Triplett

KEYS: Improve /proc/keys

2011-03-17T00:59:32+00:00

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 
Signed-off-by: James Morris

KEYS: Add an RCU payload dereference macro

2011-03-08T00:17:11+00:00

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 
Signed-off-by: Mimi Zohar 
Signed-off-by: James Morris

KEYS: Do some style cleanup in the key management code.

2011-01-21T22:59:29+00:00

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 
Signed-off-by: Linus Torvalds