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- #ifndef PQCLEAN_SPHINCSSHAKE256128FSIMPLE_AVX2_HASH_STATE_H
- #define PQCLEAN_SPHINCSSHAKE256128FSIMPLE_AVX2_HASH_STATE_H
-
- /**
- * Defines the type of the hash function state.
- *
- * Don't be fooled into thinking this instance of SPHINCS+ isn't stateless!
- *
- * From Section 7.2.2 from the SPHINCS+ round-2 specification:
- *
- * Each of the instances of the tweakable hash function take PK.seed as its
- * first input, which is constant for a given key pair – and, thus, across
- * a single signature. This leads to a lot of redundant computation. To remedy
- * this, we pad PK.seed to the length of a full 64-byte SHA-256 input block.
- * Because of the Merkle-Damgård construction that underlies SHA-256, this
- * allows for reuse of the intermediate SHA-256 state after the initial call to
- * the compression function which improves performance.
- *
- * We pass this hash state around in functions, because otherwise we need to
- * have a global variable.
- *
- * SHAKE256 does not need this state. Because this implementation is generated
- * from a shared code base, we still need to specify some hash_state as it is
- * still passed around. We chose to use an `int` as a placeholder for this
- * purpose.
- */
-
- typedef int hash_state;
-
- #endif
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