user/sven/linux.git/crypto/authenc.c, branch v3.18.75

crypto: include crypto- module prefix in template

2015-01-30T01:40:46Z

commit 4943ba16bbc2db05115707b3ff7b4874e9e3c560 upstream. This adds the module loading prefix "crypto-" to the template lookup as well. For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly includes the "crypto-" prefix at every level, correctly rejecting "vfat": net-pf-38 algif-hash crypto-vfat(blowfish) crypto-vfat(blowfish)-all crypto-vfat Reported-by: Mathias Krause Signed-off-by: Kees Cook Acked-by: Mathias Krause Signed-off-by: Herbert Xu Signed-off-by: Greg Kroah-Hartman

crypto: authenc - Find proper IV address in ablkcipher callback

2013-11-28T14:16:23Z

When performing an asynchronous ablkcipher operation the authenc completion callback routine is invoked, but it does not locate and use the proper IV. The callback routine, crypto_authenc_encrypt_done, is updated to use the same method of calculating the address of the IV as is done in crypto_authenc_encrypt function which sets up the callback. Cc: stable@vger.kernel.org Signed-off-by: Tom Lendacky Signed-off-by: Herbert Xu

crypto: authenc - Export key parsing helper function

2013-10-16T12:56:25Z

AEAD key parsing is duplicated to multiple places in the kernel. Add a common helper function to consolidate that functionality. Cc: Herbert Xu Cc: "David S. Miller" Signed-off-by: Mathias Krause Signed-off-by: Herbert Xu

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

2013-10-07T06:17:06Z

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: use ERR_CAST

2013-02-04T13:16:53Z

Replace PTR_ERR followed by ERR_PTR by ERR_CAST, to be more concise. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // @@ expression err,x; @@ - err = PTR_ERR(x); if (IS_ERR(x)) - return ERR_PTR(err); + return ERR_CAST(x); // Signed-off-by: Julia Lawall Signed-off-by: Herbert Xu

crypto: authenc - Fix crash with zero-length assoc data

2012-09-11T04:05:45Z

The authenc code doesn't deal with zero-length associated data correctly and ends up constructing a zero-length sg entry which causes a crash when it's fed into the crypto system. This patch fixes this by avoiding the code-path that triggers the SG construction if we have no associated data. This isn't the most optimal fix as it means that we'll end up using the fallback code-path even when we could still execute the digest function. However, this isn't a big deal as nobody but the test path would supply zero-length associated data. Reported-by: Romain Francoise Signed-off-by: Herbert Xu Tested-by: Romain Francoise

crypto: Use scatterwalk_crypto_chain

2010-12-02T06:47:16Z

Use scatterwalk_crypto_chain in favor of locally defined chaining functions. Signed-off-by: Steffen Klassert Signed-off-by: Herbert Xu

crypto: Use ERR_CAST

2010-05-26T00:36:51Z

Use ERR_CAST(x) rather than ERR_PTR(PTR_ERR(x)). The former makes more clear what is the purpose of the operation, which otherwise looks like a no-op. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // @@ type T; T x; identifier f; @@ T f (...) { <+... - ERR_PTR(PTR_ERR(x)) + x ...+> } @@ expression x; @@ - ERR_PTR(PTR_ERR(x)) + ERR_CAST(x) // Signed-off-by: Julia Lawall Signed-off-by: Herbert Xu

crypto: authenc - Fix cryptlen calculation

2010-05-20T09:40:31Z

This patch (applied against 2.6.34) fixes the calculation of the length of the ABLKCIPHER decrypt request ("cryptlen") after an asynchronous hash request has been completed in the AUTHENC interface. Signed-off-by: Shikhar Khattar Signed-off-by: Herbert Xu

crypto: authenc - Add EINPROGRESS check

2010-04-26T01:14:05Z

When Steffen originally wrote the authenc async hash patch, he correctly had EINPROGRESS checks in place so that we did not invoke the original completion handler with it. Unfortuantely I told him to remove it before the patch was applied. As only MAY_BACKLOG request completion handlers are required to handle EINPROGRESS completions, those checks are really needed. This patch restores them. Reported-by: Sebastian Andrzej Siewior Signed-off-by: Herbert Xu