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2018-11-20crypto: poly1305 - add Poly1305 core APIEric Biggers
Expose a low-level Poly1305 API which implements the ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305 MAC and supports block-aligned inputs only. This is needed for Adiantum hashing, which builds an εA∆U hash function from NH and a polynomial evaluation in GF(2^{130}-5); this polynomial evaluation is identical to the one the Poly1305 MAC does. However, the crypto_shash Poly1305 API isn't very appropriate for this because its calling convention assumes it is used as a MAC, with a 32-byte "one-time key" provided for every digest. But by design, in Adiantum hashing the performance of the polynomial evaluation isn't nearly as critical as NH. So it suffices to just have some C helper functions. Thus, this patch adds such functions. Acked-by: Martin Willi <martin@strongswan.org> Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-20crypto: poly1305 - use structures for key and accumulatorEric Biggers
In preparation for exposing a low-level Poly1305 API which implements the ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305 MAC and supports block-aligned inputs only, create structures poly1305_key and poly1305_state which hold the limbs of the Poly1305 "r" key and accumulator, respectively. These structures could actually have the same type (e.g. poly1305_val), but different types are preferable, to prevent misuse. Acked-by: Martin Willi <martin@strongswan.org> Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09crypto: shash - remove useless setting of type flagsEric Biggers
Many shash algorithms set .cra_flags = CRYPTO_ALG_TYPE_SHASH. But this is redundant with the C structure type ('struct shash_alg'), and crypto_register_shash() already sets the type flag automatically, clearing any type flag that was already there. Apparently the useless assignment has just been copy+pasted around. So, remove the useless assignment from all the shash algorithms. This patch shouldn't change any actual behavior. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-12crypto: poly1305 - remove ->setkey() methodEric Biggers
Since Poly1305 requires a nonce per invocation, the Linux kernel implementations of Poly1305 don't use the crypto API's keying mechanism and instead expect the key and nonce as the first 32 bytes of the data. But ->setkey() is still defined as a stub returning an error code. This prevents Poly1305 from being used through AF_ALG and will also break it completely once we start enforcing that all crypto API users (not just AF_ALG) call ->setkey() if present. Fix it by removing crypto_poly1305_setkey(), leaving ->setkey as NULL. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-05crypto: poly1305 - remove cra_alignmaskEric Biggers
Now that nothing in poly1305-generic assumes any special alignment, remove the cra_alignmask so that the crypto API does not have to unnecessarily align the buffers. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-05crypto: poly1305 - use unaligned access macros to output digestEric Biggers
Currently the only part of poly1305-generic which is assuming special alignment is the part where the final digest is written. Switch this over to the unaligned access macros so that we'll be able to remove the cra_alignmask. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-13crypto: poly1305 - Use unaligned access where requiredJason A. Donenfeld
By using the unaligned access helpers, we drastically improve performance on small MIPS routers that have to go through the exception fix-up handler for these unaligned accesses. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Reviewed-by: Eric Biggers <ebiggers@google.com> Acked-by: Martin Willi <martin@strongswan.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-07-17crypto: poly1305 - Export common Poly1305 helpersMartin Willi
As architecture specific drivers need a software fallback, export Poly1305 init/update/final functions together with some helpers in a header file. Signed-off-by: Martin Willi <martin@strongswan.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-17crypto: poly1305 - Pass key as first two message blocks to each desc_ctxMartin Willi
The Poly1305 authenticator requires a unique key for each generated tag. This implies that we can't set the key per tfm, as multiple users set individual keys. Instead we pass a desc specific key as the first two blocks of the message to authenticate in update(). Signed-off-by: Martin Willi <martin@strongswan.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-04crypto: poly1305 - Add a generic Poly1305 authenticator implementationMartin Willi
Poly1305 is a fast message authenticator designed by Daniel J. Bernstein. It is further defined in RFC7539 as a building block for the ChaCha20-Poly1305 AEAD for use in IETF protocols. This is a portable C implementation of the algorithm without architecture specific optimizations, based on public domain code by Daniel J. Bernstein and Andrew Moon. Signed-off-by: Martin Willi <martin@strongswan.org> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>