include/u-boot/sha256.h

#ifndef _SHA256_H
#define _SHA256_H

#define SHA256_SUM_LEN	32
#define SHA256_DER_LEN	19

extern const uint8_t sha256_der_prefix[];

/* Reset watchdog each time we process this many bytes */
#define CHUNKSZ_SHA256	(64 * 1024)

#ifdef CONFIG_AML_HW_SHA2

#define SHA224_DIGEST_SIZE	28

#define SHA256_DIGEST_SIZE	32
#define SHA256_BLOCK_SIZE	64

/* SHA2 context */
typedef struct {
	uint32_t h[8];
	uint32_t tot_len;
	uint32_t len;
	uint32_t digest_len;
	uint8_t block[2 * SHA256_BLOCK_SIZE];
	uint8_t buf[SHA256_DIGEST_SIZE];  /* Used to store the final digest. */
	uint8_t tmp[12]; // temp sha bits counter saved here by hw.
} sha2_ctx, sha256_context;

#else

/* SHA256 context */
typedef struct {
	uint32_t total[2];
	uint32_t state[8];
	uint8_t final_digest[32];
	uint8_t buffer[64];
} sha256_context;

#endif  /* CONFIG_AML_HW_SHA2 */

void sha256_starts(sha256_context * ctx);
void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length);
void sha256_finish(sha256_context * ctx, uint8_t digest[SHA256_SUM_LEN]);

/* Same as sha256_finish(), but returns the digest as a pointer a buffer
 * internal to the context object. This signature makes it easy to plug
 * into libavb (CONFIG_LIBAVB_PREFER_HOST_SHA256=y).
 *
 * Users call *either* sha256_finish() or sha256_final(), not both, after
 * sha256_starts() and sha256_update() calls.
 */
uint8_t *sha256_final(sha256_context * ctx);

void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
		unsigned char *output, unsigned int chunk_sz);

#endif /* _SHA256_H */