Commit Graph

63 Commits

Author SHA1 Message Date
Herbert Xu
e73d340db6 crypto: ahash - Add init_tfm/exit_tfm
This patch adds the type-safe init_tfm/exit_tfm functions to the
ahash interface.  This is meant to replace the unsafe cra_init and
cra_exit interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-08-28 16:58:28 +10:00
Ira Weiny
8afa25aa83 crypto: hash - Remove unused async iterators
Revert "crypto: hash - Add real ahash walk interface"
This reverts commit 75ecb231ff.

The callers of the functions in this commit were removed in ab8085c130

Remove these unused calls.

Fixes: ab8085c130 ("crypto: x86 - remove SHA multibuffer routines and mcryptd")
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-08-21 14:47:50 +10:00
Waiman Long
453431a549 mm, treewide: rename kzfree() to kfree_sensitive()
As said by Linus:

  A symmetric naming is only helpful if it implies symmetries in use.
  Otherwise it's actively misleading.

  In "kzalloc()", the z is meaningful and an important part of what the
  caller wants.

  In "kzfree()", the z is actively detrimental, because maybe in the
  future we really _might_ want to use that "memfill(0xdeadbeef)" or
  something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

  git grep -w --name-only kzfree |\
  xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:22 -07:00
Eric Biggers
d4fdc2dfaa crypto: algapi - enforce that all instances have a ->free() method
All instances need to have a ->free() method, but people could forget to
set it and then not notice if the instance is never unregistered.  To
help detect this bug earlier, don't allow an instance without a ->free()
method to be registered, and complain loudly if someone tries to do it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:58 +08:00
Eric Biggers
a24a1fd731 crypto: algapi - remove crypto_template::{alloc,free}()
Now that all templates provide a ->create() method which creates an
instance, installs a strongly-typed ->free() method directly to it, and
registers it, the older ->alloc() and ->free() methods in
'struct crypto_template' are no longer used.  Remove them.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:58 +08:00
Eric Biggers
48fb3e5785 crypto: hash - add support for new way of freeing instances
Add support to shash and ahash for the new way of freeing instances
(already used for skcipher, aead, and akcipher) where a ->free() method
is installed to the instance struct itself.  These methods are more
strongly-typed than crypto_template::free(), which they replace.

This will allow removing support for the old way of freeing instances.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:57 +08:00
Eric Biggers
6d1b41fce0 crypto: ahash - unexport crypto_ahash_type
Now that all the templates that need ahash spawns have been converted to
use crypto_grab_ahash() rather than look up the algorithm directly,
crypto_ahash_type is no longer used outside of ahash.c.  Make it static.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:57 +08:00
Eric Biggers
629f1afc15 crypto: algapi - remove obsoleted instance creation helpers
Remove lots of helper functions that were previously used for
instantiating crypto templates, but are now unused:

- crypto_get_attr_alg() and similar functions looked up an inner
  algorithm directly from a template parameter.  These were replaced
  with getting the algorithm's name, then calling crypto_grab_*().

- crypto_init_spawn2() and similar functions initialized a spawn, given
  an algorithm.  Similarly, these were replaced with crypto_grab_*().

- crypto_alloc_instance() and similar functions allocated an instance
  with a single spawn, given the inner algorithm.  These aren't useful
  anymore since crypto_grab_*() need the instance allocated first.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:57 +08:00
Eric Biggers
84a9c938e5 crypto: ahash - introduce crypto_grab_ahash()
Currently, ahash spawns are initialized by using ahash_attr_alg() or
crypto_find_alg() to look up the ahash algorithm, then calling
crypto_init_ahash_spawn().

This is different from how skcipher, aead, and akcipher spawns are
initialized (they use crypto_grab_*()), and for no good reason.  This
difference introduces unnecessary complexity.

The crypto_grab_*() functions used to have some problems, like not
holding a reference to the algorithm and requiring the caller to
initialize spawn->base.inst.  But those problems are fixed now.

So, let's introduce crypto_grab_ahash() so that we can convert all
templates to the same way of initializing their spawns.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09 11:30:55 +08:00
Eric Biggers
c6d633a927 crypto: algapi - make unregistration functions return void
Some of the algorithm unregistration functions return -ENOENT when asked
to unregister a non-registered algorithm, while others always return 0
or always return void.  But no users check the return value, except for
two of the bulk unregistration functions which print a message on error
but still always return 0 to their caller, and crypto_del_alg() which
calls crypto_unregister_instance() which always returns 0.

Since unregistering a non-registered algorithm is always a kernel bug
but there isn't anything callers should do to handle this situation at
runtime, let's simplify things by making all the unregistration
functions return void, and moving the error message into
crypto_unregister_alg() and upgrading it to a WARN().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-20 14:58:35 +08:00
Thomas Gleixner
2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00
Eric Biggers
77568e535a crypto: ahash - fix another early termination in hash walk
Hash algorithms with an alignmask set, e.g. "xcbc(aes-aesni)" and
"michael_mic", fail the improved hash tests because they sometimes
produce the wrong digest.  The bug is that in the case where a
scatterlist element crosses pages, not all the data is actually hashed
because the scatterlist walk terminates too early.  This happens because
the 'nbytes' variable in crypto_hash_walk_done() is assigned the number
of bytes remaining in the page, then later interpreted as the number of
bytes remaining in the scatterlist element.  Fix it.

Fixes: 900a081f69 ("crypto: ahash - Fix early termination in hash walk")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-02-08 15:30:08 +08:00
Eric Biggers
ba7d7433a0 crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
Some algorithms have a ->setkey() method that is not atomic, in the
sense that setting a key can fail after changes were already made to the
tfm context.  In this case, if a key was already set the tfm can end up
in a state that corresponds to neither the old key nor the new key.

It's not feasible to make all ->setkey() methods atomic, especially ones
that have to key multiple sub-tfms.  Therefore, make the crypto API set
CRYPTO_TFM_NEED_KEY if ->setkey() fails and the algorithm requires a
key, to prevent the tfm from being used until a new key is set.

Note: we can't set CRYPTO_TFM_NEED_KEY for OPTIONAL_KEY algorithms, so
->setkey() for those must nevertheless be atomic.  That's fine for now
since only the crc32 and crc32c algorithms set OPTIONAL_KEY, and it's
not intended that OPTIONAL_KEY be used much.

[Cc stable mainly because when introducing the NEED_KEY flag I changed
 AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG
 previously didn't have this problem.  So these "incompletely keyed"
 states became theoretically accessible via AF_ALG -- though, the
 opportunities for causing real mischief seem pretty limited.]

Fixes: 9fa68f6200 ("crypto: hash - prevent using keyed hashes without setting key")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-18 18:40:24 +08:00
Corentin Labbe
f7d76e05d0 crypto: user - fix use_after_free of struct xxx_request
All crypto_stats functions use the struct xxx_request for feeding stats,
but in some case this structure could already be freed.

For fixing this, the needed parameters (len and alg) will be stored
before the request being executed.
Fixes: cac5818c25 ("crypto: user - Implement a generic crypto statistics")
Reported-by: syzbot <syzbot+6939a606a5305e9e9799@syzkaller.appspotmail.com>

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-07 14:15:00 +08:00
Eric Biggers
37db69e0b4 crypto: user - clean up report structure copying
There have been a pretty ridiculous number of issues with initializing
the report structures that are copied to userspace by NETLINK_CRYPTO.
Commit 4473710df1 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME
expansion") replaced some strncpy()s with strlcpy()s, thereby
introducing information leaks.  Later two other people tried to replace
other strncpy()s with strlcpy() too, which would have introduced even
more information leaks:

    - https://lore.kernel.org/patchwork/patch/954991/
    - https://patchwork.kernel.org/patch/10434351/

Commit cac5818c25 ("crypto: user - Implement a generic crypto
statistics") also uses the buggy strlcpy() approach and therefore leaks
uninitialized memory to userspace.  A fix was proposed, but it was
originally incomplete.

Seeing as how apparently no one can get this right with the current
approach, change all the reporting functions to:

- Start by memsetting the report structure to 0.  This guarantees it's
  always initialized, regardless of what happens later.
- Initialize all strings using strscpy().  This is safe after the
  memset, ensures null termination of long strings, avoids unnecessary
  work, and avoids the -Wstringop-truncation warnings from gcc.
- Use sizeof(var) instead of sizeof(type).  This is more robust against
  copy+paste errors.

For simplicity, also reuse the -EMSGSIZE return value from nla_put().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-09 17:41:39 +08:00
Corentin Labbe
cac5818c25 crypto: user - Implement a generic crypto statistics
This patch implement a generic way to get statistics about all crypto
usages.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-28 12:46:25 +08:00
Kees Cook
b68a7ec1e9 crypto: hash - Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
removes the VLAs in SHASH_DESC_ON_STACK (via crypto_shash_descsize())
by using the maximum allowable size (which is now more clearly captured
in a macro), along with a few other cases. Similar limits are turned into
macros as well.

A review of existing sizes shows that SHA512_DIGEST_SIZE (64) is the
largest digest size and that sizeof(struct sha3_state) (360) is the
largest descriptor size. The corresponding maximums are reduced.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-04 11:35:03 +08:00
Herbert Xu
900a081f69 crypto: ahash - Fix early termination in hash walk
When we have an unaligned SG list entry where there is no leftover
aligned data, the hash walk code will incorrectly return zero as if
the entire SG list has been processed.

This patch fixes it by moving onto the next page instead.

Reported-by: Eli Cooper <elicooper@gmx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-03-31 01:34:19 +08:00
Kamil Konieczny
6f221f7e86 crypto: hash - Require export/import in ahash
Export and import are mandatory in async hash. As drivers were
rewritten, drop empty wrappers and correct init of ahash transformation.

Signed-off-by: Kamil Konieczny <k.konieczny@partner.samsung.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-02-15 23:24:59 +08:00
Eric Biggers
9fa68f6200 crypto: hash - prevent using keyed hashes without setting key
Currently, almost none of the keyed hash algorithms check whether a key
has been set before proceeding.  Some algorithms are okay with this and
will effectively just use a key of all 0's or some other bogus default.
However, others will severely break, as demonstrated using
"hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash
via a (potentially exploitable) stack buffer overflow.

A while ago, this problem was solved for AF_ALG by pairing each hash
transform with a 'has_key' bool.  However, there are still other places
in the kernel where userspace can specify an arbitrary hash algorithm by
name, and the kernel uses it as unkeyed hash without checking whether it
is really unkeyed.  Examples of this include:

    - KEYCTL_DH_COMPUTE, via the KDF extension
    - dm-verity
    - dm-crypt, via the ESSIV support
    - dm-integrity, via the "internal hash" mode with no key given
    - drbd (Distributed Replicated Block Device)

This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no
privileges to call.

Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the
->crt_flags of each hash transform that indicates whether the transform
still needs to be keyed or not.  Then, make the hash init, import, and
digest functions return -ENOKEY if the key is still needed.

The new flag also replaces the 'has_key' bool which algif_hash was
previously using, thereby simplifying the algif_hash implementation.

Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-12 23:03:37 +11:00
Eric Biggers
cd6ed77ad5 crypto: hash - introduce crypto_hash_alg_has_setkey()
Templates that use an shash spawn can use crypto_shash_alg_has_setkey()
to determine whether the underlying algorithm requires a key or not.
But there was no corresponding function for ahash spawns.  Add it.

Note that the new function actually has to support both shash and ahash
algorithms, since the ahash API can be used with either.

Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-12 23:03:09 +11:00
Gilad Ben-Yossef
4e5b0ad582 crypto: remove redundant backlog checks on EBUSY
Now that -EBUSY return code only indicates backlog queueing
we can safely remove the now redundant check for the
CRYPTO_TFM_REQ_MAY_BACKLOG flag when -EBUSY is returned.

Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03 22:11:17 +08:00
Rabin Vincent
6f7473c524 crypto: hash - add crypto_(un)register_ahashes()
There are already helpers to (un)register multiple normal
and AEAD algos.  Add one for ahashes too.

Signed-off-by: Lars Persson <larper@axis.com>
Signed-off-by: Rabin Vincent <rabinv@axis.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-08-22 14:54:52 +08:00
Herbert Xu
ef0579b64e crypto: ahash - Fix EINPROGRESS notification callback
The ahash API modifies the request's callback function in order
to clean up after itself in some corner cases (unaligned final
and missing finup).

When the request is complete ahash will restore the original
callback and everything is fine.  However, when the request gets
an EBUSY on a full queue, an EINPROGRESS callback is made while
the request is still ongoing.

In this case the ahash API will incorrectly call its own callback.

This patch fixes the problem by creating a temporary request
object on the stack which is used to relay EINPROGRESS back to
the original completion function.

This patch also adds code to preserve the original flags value.

Fixes: ab6bf4e5e5 ("crypto: hash - Fix the pointer voodoo in...")
Cc: <stable@vger.kernel.org>
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-04-10 19:09:18 +08:00
Gideon Israel Dsouza
d8c34b949d crypto: Replaced gcc specific attributes with macros from compiler.h
Continuing from this commit: 52f5684c8e
("kernel: use macros from compiler.h instead of __attribute__((...))")

I submitted 4 total patches. They are part of task I've taken up to
increase compiler portability in the kernel. I've cleaned up the
subsystems under /kernel /mm /block and /security, this patch targets
/crypto.

There is <linux/compiler.h> which provides macros for various gcc specific
constructs. Eg: __weak for __attribute__((weak)). I've cleaned all
instances of gcc specific attributes with the right macros for the crypto
subsystem.

I had to make one additional change into compiler-gcc.h for the case when
one wants to use this: __attribute__((aligned) and not specify an alignment
factor. From the gcc docs, this will result in the largest alignment for
that data type on the target machine so I've named the macro
__aligned_largest. Please advise if another name is more appropriate.

Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-13 00:24:39 +08:00
Herbert Xu
2495cf25f6 crypto: ahash - Add padding in crypto_ahash_extsize
The function crypto_ahash_extsize did not include padding when
computing the tfm context size.  This patch fixes this by using
the generic crypto_alg_extsize helper.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-01 23:45:03 +08:00
Herbert Xu
13f4bb78cf crypto: hash - Fix page length clamping in hash walk
The crypto hash walk code is broken when supplied with an offset
greater than or equal to PAGE_SIZE.  This patch fixes it by adjusting
walk->pg and walk->offset when this happens.

Cc: <stable@vger.kernel.org>
Reported-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-05 14:27:04 +08:00
Herbert Xu
8965450987 crypto: hash - Remove crypto_hash interface
This patch removes all traces of the crypto_hash interface, now
that everyone has switched over to shash or ahash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-02-06 15:33:20 +08:00
Herbert Xu
8d18e34c1f crypto: hash - Add crypto_has_ahash helper
This patch adds the helper crypto_has_ahash which should replace
crypto_has_hash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-25 22:42:13 +08:00
Herbert Xu
a5596d6332 crypto: hash - Add crypto_ahash_has_setkey
This patch adds a way for ahash users to determine whether a key
is required by a crypto_ahash transform.

Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-18 18:16:11 +08:00
Russell King
8996eafdcb crypto: ahash - ensure statesize is non-zero
Unlike shash algorithms, ahash drivers must implement export
and import as their descriptors may contain hardware state and
cannot be exported as is.  Unfortunately some ahash drivers did
not provide them and end up causing crashes with algif_hash.

This patch adds a check to prevent these drivers from registering
ahash algorithms until they are fixed.

Cc: stable@vger.kernel.org
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-13 22:28:10 +08:00
Cristian Stoica
5be4d4c94b crypto: replace scatterwalk_sg_next with sg_next
Modify crypto drivers to use the generic SG helper since
both of them are equivalent and the one from crypto is redundant.

See also:
  468577abe3   reverted in
  b2ab4a57b0

Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-01-26 11:34:22 +11:00
Joshua I. James
b516d51402 crypto: ahash - fixed style error in ahash.c
Fixed style error identified by checkpatch.

WARNING: Missing a blank line after declarations
+               unsigned int unaligned = alignmask + 1 - (offset & alignmask);
+               if (nbytes > unaligned)

Signed-off-by: Joshua I. James <joshua@cybercrimetech.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-12-22 23:02:36 +11:00
Tim Chen
6d9529c586 crypto: hash - initialize entry len for null input in crypto hash sg list walk
For the special case when we have a null input string, we want
to initialize the entry len to 0 for the hash/ahash walk, so
cyrpto_hash_walk_last will return the correct result indicating
that we have completed the scatter list walk.  Otherwise we may
keep walking the sg list and access bogus memory address.

Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25 20:27:16 +08:00
Herbert Xu
75ecb231ff crypto: hash - Add real ahash walk interface
Although the existing hash walk interface has already been used
by a number of ahash crypto drivers, it turns out that none of
them were really asynchronous.  They were all essentially polling
for completion.

That's why nobody has noticed until now that the walk interface
couldn't work with a real asynchronous driver since the memory
is mapped using kmap_atomic.

As we now have a use-case for a real ahash implementation on x86,
this patch creates a minimal ahash walk interface.  Basically it
just calls kmap instead of kmap_atomic and does away with the
crypto_yield call.  Real ahash crypto drivers don't need to yield
since by definition they won't be hogging the CPU.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-05-21 20:56:12 +08:00
Marek Vasut
d4a7a0fbe9 crypto: hash - Simplify the ahash_finup implementation
The ahash_def_finup() can make use of the request save/restore functions,
thus make it so. This simplifies the code a little and unifies the code
paths.

Note that the same remark about free()ing the req->priv applies here, the
req->priv can only be free()'d after the original request was restored.

Finally, squash a bug in the invocation of completion in the ASYNC path.
In both ahash_def_finup_done{1,2}, the function areq->base.complete(X, err);
was called with X=areq->base.data . This is incorrect , as X=&areq->base
is the correct value. By analysis of the data structures, we see the areq is
of type 'struct ahash_request' , areq->base is of type 'struct crypto_async_request'
and areq->base.completion is of type crypto_completion_t, which is defined in
include/linux/crypto.h as:

  typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err);

This is one lead that the X should be &areq->base . Next up, we can inspect
other code which calls the completion callback to give us kind-of statistical
idea of how this callback is used. We can try:

  $ git grep base\.complete\( drivers/crypto/

Finally, by inspecting ahash_request_set_callback() implementation defined
in include/crypto/hash.h , we observe that the .data entry of 'struct
crypto_async_request' is intended for arbitrary data, not for completion
argument.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-21 21:54:22 +08:00
Marek Vasut
1ffc9fbd1e crypto: hash - Pull out the functions to save/restore request
The functions to save original request within a newly adjusted request
and it's counterpart to restore the original request can be re-used by
more code in the crypto/ahash.c file. Pull these functions out from the
code so they're available.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-21 21:54:21 +08:00
Marek Vasut
ab6bf4e5e5 crypto: hash - Fix the pointer voodoo in unaligned ahash
Add documentation for the pointer voodoo that is happening in crypto/ahash.c
in ahash_op_unaligned(). This code is quite confusing, so add a beefy chunk
of documentation.

Moreover, make sure the mangled request is completely restored after finishing
this unaligned operation. This means restoring all of .result, .base.data
and .base.complete .

Also, remove the crypto_completion_t complete = ... line present in the
ahash_op_unaligned_done() function. This type actually declares a function
pointer, which is very confusing.

Finally, yet very important nonetheless, make sure the req->priv is free()'d
only after the original request is restored in ahash_op_unaligned_done().
The req->priv data must not be free()'d before that in ahash_op_unaligned_finish(),
since we would be accessing previously free()'d data in ahash_op_unaligned_done()
and cause corruption.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-03-21 21:54:20 +08:00
Marek Vasut
1d9a394b97 crypto: ahash - Fully restore ahash request before completing
When finishing the ahash request, the ahash_op_unaligned_done() will
call complete() on the request. Yet, this will not call the correct
complete callback. The correct complete callback was previously stored
in the requests' private data, as seen in ahash_op_unaligned(). This
patch restores the correct complete callback and .data field of the
request before calling complete() on it.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fabio Estevam <fabio.estevam@freescale.com>
Cc: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-01-05 20:49:51 +08:00
Mathias Krause
9a5467bf7b crypto: user - fix info leaks in report API
Three errors resulting in kernel memory disclosure:

1/ The structures used for the netlink based crypto algorithm report API
are located on the stack. As snprintf() does not fill the remainder of
the buffer with null bytes, those stack bytes will be disclosed to users
of the API. Switch to strncpy() to fix this.

2/ crypto_report_one() does not initialize all field of struct
crypto_user_alg. Fix this to fix the heap info leak.

3/ For the module name we should copy only as many bytes as
module_name() returns -- not as much as the destination buffer could
hold. But the current code does not and therefore copies random data
from behind the end of the module name, as the module name is always
shorter than CRYPTO_MAX_ALG_NAME.

Also switch to use strncpy() to copy the algorithm's name and
driver_name. They are strings, after all.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-02-19 20:27:03 +08:00
David S. Miller
6662df33f8 crypto: Stop using NLA_PUT*().
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-04-02 04:33:42 -04:00
Cong Wang
f0dfc0b0b7 crypto: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:16 +08:00
Herbert Xu
3acc84739d crypto: algapi - Fix build problem with NET disabled
The report functions use NLA_PUT so we need to ensure that NET
is enabled.

Reported-by: Luis Henriques <henrix@camandro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-11-11 06:57:06 +08:00
Steffen Klassert
6238cbaec4 crypto: Add userspace report for ahash type algorithms
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-21 14:24:04 +02:00
Szilveszter Ördög
23a75eee07 crypto: hash - Fix handling of small unaligned buffers
If a scatterwalk chain contains an entry with an unaligned offset then
hash_walk_next() will cut off the next step at the next alignment point.

However, if the entry ends before the next alignment point then we a loop,
which leads to a kernel oops.

Fix this by checking whether the next aligment point is before the end of the
current entry.

Signed-off-by: Szilveszter Ördög <slipszi@gmail.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-08-06 09:26:38 +08:00
Szilveszter Ördög
cbb9bf65ae crypto: hash - Fix handling of unaligned buffers
The correct way to calculate the start of the aligned part of an
unaligned buffer is:

  offset = ALIGN(offset, alignmask + 1);

However, crypto_hash_walk_done() has:

  offset += alignmask - 1;
  offset = ALIGN(offset, alignmask + 1);

which actually skips a whole block unless offset % (alignmask + 1) == 1.

This patch fixes the problem.

Signed-off-by: Szilveszter Ördög <slipszi@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-03-03 08:03:23 +08:00
Steffen Klassert
5befbd5a7e crypto: ahash - Use GFP_KERNEL on allocation if the request can sleep
ahash_op_unaligned() and ahash_def_finup() allocate memory atomically,
regardless whether the request can sleep or not. This patch changes
this to use GFP_KERNEL if the request can sleep.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-24 13:56:31 +08:00
Herbert Xu
a70c522520 crypto: ahash - Fix setkey crash
When the alignment check was made unconditional for ahash we
may end up crashing on shash algorithms because we're always
calling alg->setkey instead of tfm->setkey.

This patch fixes it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-15 20:39:05 +08:00
Herbert Xu
66f6ce5e52 crypto: ahash - Add unaligned handling and default operations
This patch exports the finup operation where available and adds
a default finup operation for ahash.  The operations final, finup
and digest also will now deal with unaligned result pointers by
copying it.  Finally export/import operations are will now be
exported too.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-15 12:40:40 +08:00
Herbert Xu
093900c2b9 crypto: ahash - Use GFP_KERNEL in unaligned setkey
We currently use GFP_ATOMIC in the unaligned setkey function
to allocate the temporary aligned buffer.  Since setkey must
be called in a sleepable context, we can use GFP_KERNEL instead.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-14 21:48:35 +08:00