// Copyright (c) 2014-2022, The Monero Project
//
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//    of conditions and the following disclaimer in the documentation and/or other
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#ifndef HMAC_KECCAK_H
#define HMAC_KECCAK_H

#include "keccak.h"

// HMAC RFC 2104 with Keccak-256 base hash function
//
// B = KECCAK_BLOCKLEN = 136 B
// L = HASH_SIZE = 32 B
//
// Note this is not HMAC-SHA3 as SHA3 and Keccak differs in
// the padding constant.

#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
  KECCAK_CTX inner;
  KECCAK_CTX outer;
} hmac_keccak_state;

void hmac_keccak_init(hmac_keccak_state *S, const uint8_t *_key, size_t keylen);
void hmac_keccak_update(hmac_keccak_state *S, const uint8_t *data, size_t datalen);
void hmac_keccak_finish(hmac_keccak_state *S, uint8_t *digest);
void hmac_keccak_hash(uint8_t *out, const uint8_t *key, size_t keylen, const uint8_t *in, size_t inlen);

#ifdef __cplusplus
}
#endif
#endif //HMAC_KECCAK_H