/* hash.h — SHA-1 and SHA-256, the throughput-critical primitives.
 *
 * SHA-1 backs BitTorrent v1 (piece hashes + info-hash). SHA-256 backs v2
 * (Merkle leaves + info-hash). SHA-256 has a runtime-dispatched SHA-NI path so
 * a single core verifies well above the 1.25 GB/s the 10 GbE target demands;
 * the portable scalar path is the fallback and the cross-check oracle.
 */
#ifndef NAUT_HASH_H
#define NAUT_HASH_H

#include "naut/common.h"

#define NAUT_SHA1_LEN   20
#define NAUT_SHA256_LEN 32

/* --- SHA-1 ------------------------------------------------------------- */
typedef struct {
    uint32_t h[5];
    uint64_t len;            /* total bytes hashed */
    uint8_t  block[64];
    size_t   used;
} naut_sha1_ctx;

void naut_sha1_init(naut_sha1_ctx *c);
void naut_sha1_update(naut_sha1_ctx *c, const void *data, size_t len);
void naut_sha1_final(naut_sha1_ctx *c, uint8_t out[NAUT_SHA1_LEN]);
void naut_sha1(const void *data, size_t len, uint8_t out[NAUT_SHA1_LEN]);

/* --- SHA-256 ----------------------------------------------------------- */
typedef struct {
    uint32_t h[8];
    uint64_t len;
    uint8_t  block[64];
    size_t   used;
} naut_sha256_ctx;

void naut_sha256_init(naut_sha256_ctx *c);
void naut_sha256_update(naut_sha256_ctx *c, const void *data, size_t len);
void naut_sha256_final(naut_sha256_ctx *c, uint8_t out[NAUT_SHA256_LEN]);
void naut_sha256(const void *data, size_t len, uint8_t out[NAUT_SHA256_LEN]);

/* Which SHA-256 backend was selected at startup ("sha-ni" or "scalar"). */
const char *naut_sha256_backend(void);

#endif /* NAUT_HASH_H */