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<title>user/sven/linux.git/include/crypto/algapi.h, branch v4.0</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v4.0</id>
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<updated>2014-06-20T13:26:04Z</updated>
<entry>
<title>crypto: api - Move crypto_yield() to algapi.h</title>
<updated>2014-06-20T13:26:04Z</updated>
<author>
<name>Marek Vasut</name>
<email>marex@denx.de</email>
</author>
<published>2014-05-26T13:32:05Z</published>
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<id>urn:sha1:bb55a4c100abbb8d2a41e732f6362c575a7094e6</id>
<content type='text'>
It makes no sense for crypto_yield() to be defined in scatterwalk.h ,
move it into algapi.h as it's an internal function to crypto API.

Signed-off-by: Marek Vasut &lt;marex@denx.de&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: allow blkcipher walks over AEAD data</title>
<updated>2014-03-10T12:17:11Z</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2014-03-04T05:28:39Z</published>
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<id>urn:sha1:4f7f1d7cff8f2c170ce0319eb4c01a82c328d34f</id>
<content type='text'>
This adds the function blkcipher_aead_walk_virt_block, which allows the caller
to use the blkcipher walk API to handle the input and output scatterlists.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: remove direct blkcipher_walk dependency on transform</title>
<updated>2014-03-10T12:17:10Z</updated>
<author>
<name>Ard Biesheuvel</name>
<email>ard.biesheuvel@linaro.org</email>
</author>
<published>2014-03-04T05:28:38Z</published>
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<id>urn:sha1:822be00fe67105a90e536df52d1e4d688f34b5b2</id>
<content type='text'>
In order to allow other uses of the blkcipher walk API than the blkcipher
algos themselves, this patch copies some of the transform data members to the
walk struct so the transform is only accessed at walk init time.

Signed-off-by: Ard Biesheuvel &lt;ard.biesheuvel@linaro.org&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks</title>
<updated>2013-10-07T06:17:06Z</updated>
<author>
<name>James Yonan</name>
<email>james@openvpn.net</email>
</author>
<published>2013-09-26T08:20:39Z</published>
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<id>urn:sha1:6bf37e5aa90f18baf5acf4874bca505dd667c37f</id>
<content type='text'>
When comparing MAC hashes, AEAD authentication tags, or other hash
values in the context of authentication or integrity checking, it
is important not to leak timing information to a potential attacker,
i.e. when communication happens over a network.

Bytewise memory comparisons (such as memcmp) are usually optimized so
that they return a nonzero value as soon as a mismatch is found. E.g,
on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch
and up to ~850 cyc for a full match (cold). This early-return behavior
can leak timing information as a side channel, allowing an attacker to
iteratively guess the correct result.

This patch adds a new method crypto_memneq ("memory not equal to each
other") to the crypto API that compares memory areas of the same length
in roughly "constant time" (cache misses could change the timing, but
since they don't reveal information about the content of the strings
being compared, they are effectively benign). Iow, best and worst case
behaviour take the same amount of time to complete (in contrast to
memcmp).

Note that crypto_memneq (unlike memcmp) can only be used to test for
equality or inequality, NOT for lexicographical order. This, however,
is not an issue for its use-cases within the crypto API.

We tried to locate all of the places in the crypto API where memcmp was
being used for authentication or integrity checking, and convert them
over to crypto_memneq.

crypto_memneq is declared noinline, placed in its own source file,
and compiled with optimizations that might increase code size disabled
("Os") because a smart compiler (or LTO) might notice that the return
value is always compared against zero/nonzero, and might then
reintroduce the same early-return optimization that we are trying to
avoid.

Using #pragma or __attribute__ optimization annotations of the code
for disabling optimization was avoided as it seems to be considered
broken or unmaintained for long time in GCC [1]. Therefore, we work
around that by specifying the compile flag for memneq.o directly in
the Makefile. We found that this seems to be most appropriate.

As we use ("Os"), this patch also provides a loop-free "fast-path" for
frequently used 16 byte digests. Similarly to kernel library string
functions, leave an option for future even further optimized architecture
specific assembler implementations.

This was a joint work of James Yonan and Daniel Borkmann. Also thanks
for feedback from Florian Weimer on this and earlier proposals [2].

  [1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html
  [2] https://lkml.org/lkml/2013/2/10/131

Signed-off-by: James Yonan &lt;james@openvpn.net&gt;
Signed-off-by: Daniel Borkmann &lt;dborkman@redhat.com&gt;
Cc: Florian Weimer &lt;fw@deneb.enyo.de&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: Unlink and free instances when deleted</title>
<updated>2011-11-09T04:04:06Z</updated>
<author>
<name>Steffen Klassert</name>
<email>steffen.klassert@secunet.com</email>
</author>
<published>2011-11-08T09:09:17Z</published>
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<id>urn:sha1:ce3fd840f588d85a8c1be651cf90fa1ba1f029e9</id>
<content type='text'>
We leak the crypto instance when we unregister an instance with
crypto_del_alg(). Therefore we introduce crypto_unregister_instance()
to unlink the crypto instance from the template's instances list and
to free the recources of the instance properly.

Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: Add a report function pointer to crypto_type</title>
<updated>2011-10-21T12:24:03Z</updated>
<author>
<name>Steffen Klassert</name>
<email>steffen.klassert@secunet.com</email>
</author>
<published>2011-09-27T05:24:29Z</published>
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<id>urn:sha1:b6aa63c09ba3b150a1030f9c95c7647361e7910e</id>
<content type='text'>
We add a report function pointer to struct crypto_type. This function
pointer is used from the crypto userspace configuration API to report
crypto algorithms to userspace.

Signed-off-by: Steffen Klassert &lt;steffen.klassert@secunet.com&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: skcipher - Add ablkcipher_walk interfaces</title>
<updated>2010-05-19T04:13:07Z</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2010-05-19T04:13:07Z</published>
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<id>urn:sha1:bf06099db18a1244957076e51847c644cfe46808</id>
<content type='text'>
These are akin to the blkcipher_walk helpers.

The main differences in the async variant are:

1) Only physical walking is supported.  We can't hold on to
   kmap mappings across the async operation to support virtual
   ablkcipher_walk operations anyways.

2) Bounce buffers used for async more need to be persistent and
   freed at a later point in time when the async op completes.
   Therefore we maintain a list of writeback buffers and require
   that the ablkcipher_walk user call the 'complete' operation
   so we can copy the bounce buffers out to the real buffers and
   free up the bounce buffer chunks.

These interfaces will be used by the new Niagara2 crypto driver.

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>crypto: hash - Remove legacy hash/digest code</title>
<updated>2009-10-19T03:53:37Z</updated>
<author>
<name>Benjamin Gilbert</name>
<email>bgilbert@cs.cmu.edu</email>
</author>
<published>2009-10-19T03:53:37Z</published>
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<id>urn:sha1:2141b6309b1fce535329c195cb5e5274a4c84ebc</id>
<content type='text'>
6941c3a0 disabled compilation of the legacy digest code but didn't
actually remove it.  Rectify this.  Also, remove the crypto_hash_type
extern declaration from algapi.h now that the struct is gone.

Signed-off-by: Benjamin Gilbert &lt;bgilbert@cs.cmu.edu&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6</title>
<updated>2009-09-11T16:38:37Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2009-09-11T16:38:37Z</published>
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<id>urn:sha1:332a3392188e0ad966543c87b8da2b9d246f301d</id>
<content type='text'>
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (102 commits)
  crypto: sha-s390 - Fix warnings in import function
  crypto: vmac - New hash algorithm for intel_txt support
  crypto: api - Do not displace newly registered algorithms
  crypto: ansi_cprng - Fix module initialization
  crypto: xcbc - Fix alignment calculation of xcbc_tfm_ctx
  crypto: fips - Depend on ansi_cprng
  crypto: blkcipher - Do not use eseqiv on stream ciphers
  crypto: ctr - Use chainiv on raw counter mode
  Revert crypto: fips - Select CPRNG
  crypto: rng - Fix typo
  crypto: talitos - add support for 36 bit addressing
  crypto: talitos - align locks on cache lines
  crypto: talitos - simplify hmac data size calculation
  crypto: mv_cesa - Add support for Orion5X crypto engine
  crypto: cryptd - Add support to access underlaying shash
  crypto: gcm - Use GHASH digest algorithm
  crypto: ghash - Add GHASH digest algorithm for GCM
  crypto: authenc - Convert to ahash
  crypto: api - Fix aligned ctx helper
  crypto: hmac - Prehash ipad/opad
  ...
</content>
</entry>
<entry>
<title>crypto: skcipher - Fix skcipher_dequeue_givcrypt NULL test</title>
<updated>2009-08-29T10:44:04Z</updated>
<author>
<name>Herbert Xu</name>
<email>herbert@gondor.apana.org.au</email>
</author>
<published>2009-08-29T10:44:04Z</published>
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<id>urn:sha1:0c7d400fafaeab6014504a6a6249f01bac7f7db4</id>
<content type='text'>
As struct skcipher_givcrypt_request includes struct crypto_request
at a non-zero offset, testing for NULL after converting the pointer
returned by crypto_dequeue_request does not work.  This can result
in IPsec crashes when the queue is depleted.

This patch fixes it by doing the pointer conversion only when the
return value is non-NULL.  In particular, we create a new function
__crypto_dequeue_request that does the pointer conversion.

Reported-by: Brad Bosch &lt;bradbosch@comcast.net&gt;
Signed-off-by: Herbert Xu &lt;herbert@gondor.apana.org.au&gt;
</content>
</entry>
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