BMC/Intel-BMC/linux.git/include/crypto/algapi.h, branch v4.2

crypto: aead - Convert top level interface to new style

2015-05-13T02:31:53+00:00

This patch converts the top-level aead interface to the new style. All user-level AEAD interface code have been moved into crypto/aead.h. The allocation/free functions have switched over to the new way of allocating tfms. This patch also removes the double indrection on setkey so the indirection now exists only at the alg level. Apart from these there are no user-visible changes. Signed-off-by: Herbert Xu

crypto: api - Add crypto_grab_spawn primitive

2015-05-13T02:31:25+00:00

This patch adds a new primitive crypto_grab_spawn which is meant to replace crypto_init_spawn and crypto_init_spawn2. Under the new scheme the user no longer has to worry about reference counting the alg object before it is subsumed by the spawn. It is pretty much an exact copy of crypto_grab_aead. Prior to calling this function spawn->frontend and spawn->inst must have been set. Signed-off-by: Herbert Xu

crypto: api - Change crypto_unregister_instance argument type

2015-04-03T09:53:32+00:00

This patch makes crypto_unregister_instance take a crypto_instance instead of a crypto_alg. This allows us to remove a duplicate CRYPTO_ALG_INSTANCE check in crypto_unregister_instance. Signed-off-by: Herbert Xu

crypto: api - Move crypto_yield() to algapi.h

2014-06-20T13:26:04+00:00

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 Signed-off-by: Herbert Xu

crypto: allow blkcipher walks over AEAD data

2014-03-10T12:17:11+00:00

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 Signed-off-by: Herbert Xu

crypto: remove direct blkcipher_walk dependency on transform

2014-03-10T12:17:10+00:00

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 Signed-off-by: Herbert Xu

crypto: crypto_memneq - add equality testing of memory regions w/o timing leaks

2013-10-07T06:17:06+00:00

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 Signed-off-by: Daniel Borkmann Cc: Florian Weimer Signed-off-by: Herbert Xu

crypto: Unlink and free instances when deleted

2011-11-09T04:04:06+00:00

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 Signed-off-by: Herbert Xu

crypto: Add a report function pointer to crypto_type

2011-10-21T12:24:03+00:00

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 Signed-off-by: Herbert Xu

crypto: skcipher - Add ablkcipher_walk interfaces

2010-05-19T04:13:07+00:00

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 Signed-off-by: Herbert Xu