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Diffstat (limited to 'nettle.texinfo')
| -rw-r--r-- | nettle.texinfo | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/nettle.texinfo b/nettle.texinfo index 5eb5752d..2df85e77 100644 --- a/nettle.texinfo +++ b/nettle.texinfo @@ -834,6 +834,28 @@ octets of the digest are written. This function also resets the context. @end deftypefun +@subsubsection @acronym{SHAKE-256} +@cindex SHAKE + +In addition to those SHA-3 hash functions, Nettle also provides a SHA-3 +extendable-output function (XOF), SHAKE-256. Unlike SHA-3 hash functions, +SHAKE can produce an output digest of any desired length. + +To use SHAKE256, the context struct, init and update functions are the +same as for SHA3-256. To get a SHAKE256 digest, the following function +is used instead of @code{sha3_256_digest}. For an output size of +@code{SHA3_256_DIGEST_SIZE}, security is equivalent to SHA3-256 (but the +digest is different). Increasing output size further does not increase +security in terms of collision or preimage resistance. It can be seen as +a built in pseudorandomness generator. + +@deftypefun void sha3_256_shake (struct shake256_ctx *@var{ctx}, size_t @var{length}, uint8_t *@var{digest}) +Performs final processing and produces a SHAKE256 digest, writing it +to @var{digest}. @var{length} can be of arbitrary size. + +This function also resets the context. +@end deftypefun + @node Legacy hash functions, nettle_hash abstraction, Recommended hash functions, Hash functions @comment node-name, next, previous, up @subsection Legacy hash functions |