crypto/blake2b_generic.c - SHIFTPHONES/mainline/linux - Gitiles

 // SPDX-License-Identifier: (GPL-2.0-only OR Apache-2.0)
 /*
  * BLAKE2b reference source code package - reference C implementations
  *
  * Copyright 2012, Samuel Neves <sneves@dei.uc.pt>.  You may use this under the
  * terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
  * your option.  The terms of these licenses can be found at:
  *
  * - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
  * - OpenSSL license   : https://www.openssl.org/source/license.html
  * - Apache 2.0        : http://www.apache.org/licenses/LICENSE-2.0
  *
  * More information about the BLAKE2 hash function can be found at
  * https://blake2.net.
  *
  * Note: the original sources have been modified for inclusion in linux kernel
  * in terms of coding style, using generic helpers and simplifications of error
  * handling.
  */

 #include <asm/unaligned.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/bitops.h>
 #include <crypto/internal/hash.h>

 #define BLAKE2B_160_DIGEST_SIZE		(160 / 8)
 #define BLAKE2B_256_DIGEST_SIZE		(256 / 8)
 #define BLAKE2B_384_DIGEST_SIZE		(384 / 8)
 #define BLAKE2B_512_DIGEST_SIZE		(512 / 8)

 enum blake2b_constant {
 	BLAKE2B_BLOCKBYTES    = 128,
 	BLAKE2B_OUTBYTES      = 64,
 	BLAKE2B_KEYBYTES      = 64,
 	BLAKE2B_SALTBYTES     = 16,
 	BLAKE2B_PERSONALBYTES = 16
 };

 struct blake2b_state {
 	u64      h[8];
 	u64      t[2];
 	u64      f[2];
 	u8       buf[BLAKE2B_BLOCKBYTES];
 	size_t   buflen;
 	size_t   outlen;
 	u8       last_node;
 };

 struct blake2b_param {
 	u8 digest_length;			/* 1 */
 	u8 key_length;				/* 2 */
 	u8 fanout;				/* 3 */
 	u8 depth;				/* 4 */
 	__le32 leaf_length;			/* 8 */
 	__le32 node_offset;			/* 12 */
 	__le32 xof_length;			/* 16 */
 	u8 node_depth;				/* 17 */
 	u8 inner_length;			/* 18 */
 	u8 reserved[14];			/* 32 */
 	u8 salt[BLAKE2B_SALTBYTES];		/* 48 */
 	u8 personal[BLAKE2B_PERSONALBYTES];	/* 64 */
 } __packed;

 static const u64 blake2b_IV[8] = {
 	0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL,
 	0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL,
 	0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
 	0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL
 };

 static const u8 blake2b_sigma[12][16] = {
 	{  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15 },
 	{ 14, 10,  4,  8,  9, 15, 13,  6,  1, 12,  0,  2, 11,  7,  5,  3 },
 	{ 11,  8, 12,  0,  5,  2, 15, 13, 10, 14,  3,  6,  7,  1,  9,  4 },
 	{  7,  9,  3,  1, 13, 12, 11, 14,  2,  6,  5, 10,  4,  0, 15,  8 },
 	{  9,  0,  5,  7,  2,  4, 10, 15, 14,  1, 11, 12,  6,  8,  3, 13 },
 	{  2, 12,  6, 10,  0, 11,  8,  3,  4, 13,  7,  5, 15, 14,  1,  9 },
 	{ 12,  5,  1, 15, 14, 13,  4, 10,  0,  7,  6,  3,  9,  2,  8, 11 },
 	{ 13, 11,  7, 14, 12,  1,  3,  9,  5,  0, 15,  4,  8,  6,  2, 10 },
 	{  6, 15, 14,  9, 11,  3,  0,  8, 12,  2, 13,  7,  1,  4, 10,  5 },
 	{ 10,  2,  8,  4,  7,  6,  1,  5, 15, 11,  9, 14,  3, 12, 13,  0 },
 	{  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15 },
 	{ 14, 10,  4,  8,  9, 15, 13,  6,  1, 12,  0,  2, 11,  7,  5,  3 }
 };

 static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen);

 static void blake2b_set_lastnode(struct blake2b_state *S)
 {
 	S->f[1] = (u64)-1;
 }

 static void blake2b_set_lastblock(struct blake2b_state *S)
 {
 	if (S->last_node)
 		blake2b_set_lastnode(S);

 	S->f[0] = (u64)-1;
 }

 static void blake2b_increment_counter(struct blake2b_state *S, const u64 inc)
 {
 	S->t[0] += inc;
 	S->t[1] += (S->t[0] < inc);
 }

 static void blake2b_init0(struct blake2b_state *S)
 {
 	size_t i;

 	memset(S, 0, sizeof(struct blake2b_state));

 	for (i = 0; i < 8; ++i)
 		S->h[i] = blake2b_IV[i];
 }

 /* init xors IV with input parameter block */
 static void blake2b_init_param(struct blake2b_state *S,
 			       const struct blake2b_param *P)
 {
 	const u8 *p = (const u8 *)(P);
 	size_t i;

 	blake2b_init0(S);

 	/* IV XOR ParamBlock */
 	for (i = 0; i < 8; ++i)
 		S->h[i] ^= get_unaligned_le64(p + sizeof(S->h[i]) * i);

 	S->outlen = P->digest_length;
 }

 static void blake2b_init(struct blake2b_state *S, size_t outlen)
 {
 	struct blake2b_param P;

 	P.digest_length = (u8)outlen;
 	P.key_length    = 0;
 	P.fanout        = 1;
 	P.depth         = 1;
 	P.leaf_length   = 0;
 	P.node_offset   = 0;
 	P.xof_length    = 0;
 	P.node_depth    = 0;
 	P.inner_length  = 0;
 	memset(P.reserved, 0, sizeof(P.reserved));
 	memset(P.salt,     0, sizeof(P.salt));
 	memset(P.personal, 0, sizeof(P.personal));
 	blake2b_init_param(S, &P);
 }

 static void blake2b_init_key(struct blake2b_state *S, size_t outlen,
 			     const void *key, size_t keylen)
 {
 	struct blake2b_param P;

 	P.digest_length = (u8)outlen;
 	P.key_length    = (u8)keylen;
 	P.fanout        = 1;
 	P.depth         = 1;
 	P.leaf_length   = 0;
 	P.node_offset   = 0;
 	P.xof_length    = 0;
 	P.node_depth    = 0;
 	P.inner_length  = 0;
 	memset(P.reserved, 0, sizeof(P.reserved));
 	memset(P.salt,     0, sizeof(P.salt));
 	memset(P.personal, 0, sizeof(P.personal));

 	blake2b_init_param(S, &P);

 	{
 		u8 block[BLAKE2B_BLOCKBYTES];

 		memset(block, 0, BLAKE2B_BLOCKBYTES);
 		memcpy(block, key, keylen);
 		blake2b_update(S, block, BLAKE2B_BLOCKBYTES);
 		memzero_explicit(block, BLAKE2B_BLOCKBYTES);
 	}
 }

 #define G(r,i,a,b,c,d)                                  \
 	do {                                            \
 		a = a + b + m[blake2b_sigma[r][2*i+0]]; \
 		d = ror64(d ^ a, 32);                   \
 		c = c + d;                              \
 		b = ror64(b ^ c, 24);                   \
 		a = a + b + m[blake2b_sigma[r][2*i+1]]; \
 		d = ror64(d ^ a, 16);                   \
 		c = c + d;                              \
 		b = ror64(b ^ c, 63);                   \
 	} while (0)

 #define ROUND(r)                                \
 	do {                                    \
 		G(r,0,v[ 0],v[ 4],v[ 8],v[12]); \
 		G(r,1,v[ 1],v[ 5],v[ 9],v[13]); \
 		G(r,2,v[ 2],v[ 6],v[10],v[14]); \
 		G(r,3,v[ 3],v[ 7],v[11],v[15]); \
 		G(r,4,v[ 0],v[ 5],v[10],v[15]); \
 		G(r,5,v[ 1],v[ 6],v[11],v[12]); \
 		G(r,6,v[ 2],v[ 7],v[ 8],v[13]); \
 		G(r,7,v[ 3],v[ 4],v[ 9],v[14]); \
 	} while (0)

 static void blake2b_compress(struct blake2b_state *S,
 			     const u8 block[BLAKE2B_BLOCKBYTES])
 {
 	u64 m[16];
 	u64 v[16];
 	size_t i;

 	for (i = 0; i < 16; ++i)
 		m[i] = get_unaligned_le64(block + i * sizeof(m[i]));

 	for (i = 0; i < 8; ++i)
 		v[i] = S->h[i];

 	v[ 8] = blake2b_IV[0];
 	v[ 9] = blake2b_IV[1];
 	v[10] = blake2b_IV[2];
 	v[11] = blake2b_IV[3];
 	v[12] = blake2b_IV[4] ^ S->t[0];
 	v[13] = blake2b_IV[5] ^ S->t[1];
 	v[14] = blake2b_IV[6] ^ S->f[0];
 	v[15] = blake2b_IV[7] ^ S->f[1];

 	ROUND(0);
 	ROUND(1);
 	ROUND(2);
 	ROUND(3);
 	ROUND(4);
 	ROUND(5);
 	ROUND(6);
 	ROUND(7);
 	ROUND(8);
 	ROUND(9);
 	ROUND(10);
 	ROUND(11);

 	for (i = 0; i < 8; ++i)
 		S->h[i] = S->h[i] ^ v[i] ^ v[i + 8];
 }

 #undef G
 #undef ROUND

 static void blake2b_update(struct blake2b_state *S, const void *pin, size_t inlen)
 {
 	const u8 *in = (const u8 *)pin;

 	if (inlen > 0) {
 		size_t left = S->buflen;
 		size_t fill = BLAKE2B_BLOCKBYTES - left;

 		if (inlen > fill) {
 			S->buflen = 0;
 			/* Fill buffer */
 			memcpy(S->buf + left, in, fill);
 			blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
 			/* Compress */
 			blake2b_compress(S, S->buf);
 			in += fill;
 			inlen -= fill;
 			while (inlen > BLAKE2B_BLOCKBYTES) {
 				blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
 				blake2b_compress(S, in);
 				in += BLAKE2B_BLOCKBYTES;
 				inlen -= BLAKE2B_BLOCKBYTES;
 			}
 		}
 		memcpy(S->buf + S->buflen, in, inlen);
 		S->buflen += inlen;
 	}
 }

 static void blake2b_final(struct blake2b_state *S, void *out, size_t outlen)
 {
 	u8 buffer[BLAKE2B_OUTBYTES] = {0};
 	size_t i;

 	blake2b_increment_counter(S, S->buflen);
 	blake2b_set_lastblock(S);
 	/* Padding */
 	memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen);
 	blake2b_compress(S, S->buf);

 	/* Output full hash to temp buffer */
 	for (i = 0; i < 8; ++i)
 		put_unaligned_le64(S->h[i], buffer + sizeof(S->h[i]) * i);

 	memcpy(out, buffer, S->outlen);
 	memzero_explicit(buffer, sizeof(buffer));
 }

 struct digest_tfm_ctx {
 	u8 key[BLAKE2B_KEYBYTES];
 	unsigned int keylen;
 };

 static int digest_setkey(struct crypto_shash *tfm, const u8 *key,
 			 unsigned int keylen)
 {
 	struct digest_tfm_ctx *mctx = crypto_shash_ctx(tfm);

 	if (keylen == 0 || keylen > BLAKE2B_KEYBYTES) {
 		crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 		return -EINVAL;
 	}

 	memcpy(mctx->key, key, keylen);
 	mctx->keylen = keylen;

 	return 0;
 }

 static int digest_init(struct shash_desc *desc)
 {
 	struct digest_tfm_ctx *mctx = crypto_shash_ctx(desc->tfm);
 	struct blake2b_state *state = shash_desc_ctx(desc);
 	const int digestsize = crypto_shash_digestsize(desc->tfm);

 	if (mctx->keylen == 0)
 		blake2b_init(state, digestsize);
 	else
 		blake2b_init_key(state, digestsize, mctx->key, mctx->keylen);
 	return 0;
 }

 static int digest_update(struct shash_desc *desc, const u8 *data,
 			 unsigned int length)
 {
 	struct blake2b_state *state = shash_desc_ctx(desc);

 	blake2b_update(state, data, length);
 	return 0;
 }

 static int digest_final(struct shash_desc *desc, u8 *out)
 {
 	struct blake2b_state *state = shash_desc_ctx(desc);
 	const int digestsize = crypto_shash_digestsize(desc->tfm);

 	blake2b_final(state, out, digestsize);
 	return 0;
 }

 static struct shash_alg blake2b_algs[] = {
 	{
 		.base.cra_name		= "blake2b-160",
 		.base.cra_driver_name	= "blake2b-160-generic",
 		.base.cra_priority	= 100,
 		.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.base.cra_blocksize	= BLAKE2B_BLOCKBYTES,
 		.base.cra_ctxsize	= sizeof(struct digest_tfm_ctx),
 		.base.cra_module	= THIS_MODULE,
 		.digestsize		= BLAKE2B_160_DIGEST_SIZE,
 		.setkey			= digest_setkey,
 		.init			= digest_init,
 		.update			= digest_update,
 		.final			= digest_final,
 		.descsize		= sizeof(struct blake2b_state),
 	}, {
 		.base.cra_name		= "blake2b-256",
 		.base.cra_driver_name	= "blake2b-256-generic",
 		.base.cra_priority	= 100,
 		.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.base.cra_blocksize	= BLAKE2B_BLOCKBYTES,
 		.base.cra_ctxsize	= sizeof(struct digest_tfm_ctx),
 		.base.cra_module	= THIS_MODULE,
 		.digestsize		= BLAKE2B_256_DIGEST_SIZE,
 		.setkey			= digest_setkey,
 		.init			= digest_init,
 		.update			= digest_update,
 		.final			= digest_final,
 		.descsize		= sizeof(struct blake2b_state),
 	}, {
 		.base.cra_name		= "blake2b-384",
 		.base.cra_driver_name	= "blake2b-384-generic",
 		.base.cra_priority	= 100,
 		.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.base.cra_blocksize	= BLAKE2B_BLOCKBYTES,
 		.base.cra_ctxsize	= sizeof(struct digest_tfm_ctx),
 		.base.cra_module	= THIS_MODULE,
 		.digestsize		= BLAKE2B_384_DIGEST_SIZE,
 		.setkey			= digest_setkey,
 		.init			= digest_init,
 		.update			= digest_update,
 		.final			= digest_final,
 		.descsize		= sizeof(struct blake2b_state),
 	}, {
 		.base.cra_name		= "blake2b-512",
 		.base.cra_driver_name	= "blake2b-512-generic",
 		.base.cra_priority	= 100,
 		.base.cra_flags		= CRYPTO_ALG_OPTIONAL_KEY,
 		.base.cra_blocksize	= BLAKE2B_BLOCKBYTES,
 		.base.cra_ctxsize	= sizeof(struct digest_tfm_ctx),
 		.base.cra_module	= THIS_MODULE,
 		.digestsize		= BLAKE2B_512_DIGEST_SIZE,
 		.setkey			= digest_setkey,
 		.init			= digest_init,
 		.update			= digest_update,
 		.final			= digest_final,
 		.descsize		= sizeof(struct blake2b_state),
 	}
 };

 static int __init blake2b_mod_init(void)
 {
 	BUILD_BUG_ON(sizeof(struct blake2b_param) != BLAKE2B_OUTBYTES);

 	return crypto_register_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs));
 }

 static void __exit blake2b_mod_fini(void)
 {
 	crypto_unregister_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs));
 }

 subsys_initcall(blake2b_mod_init);
 module_exit(blake2b_mod_fini);

 MODULE_AUTHOR("David Sterba <kdave@kernel.org>");
 MODULE_DESCRIPTION("BLAKE2b generic implementation");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS_CRYPTO("blake2b-160");
 MODULE_ALIAS_CRYPTO("blake2b-160-generic");
 MODULE_ALIAS_CRYPTO("blake2b-256");
 MODULE_ALIAS_CRYPTO("blake2b-256-generic");
 MODULE_ALIAS_CRYPTO("blake2b-384");
 MODULE_ALIAS_CRYPTO("blake2b-384-generic");
 MODULE_ALIAS_CRYPTO("blake2b-512");
 MODULE_ALIAS_CRYPTO("blake2b-512-generic");
	// SPDX-License-Identifier: (GPL-2.0-only OR Apache-2.0)
	/*
	* BLAKE2b reference source code package - reference C implementations
	*
	* Copyright 2012, Samuel Neves <sneves@dei.uc.pt>. You may use this under the
	* terms of the CC0, the OpenSSL Licence, or the Apache Public License 2.0, at
	* your option. The terms of these licenses can be found at:
	*
	* - CC0 1.0 Universal : http://creativecommons.org/publicdomain/zero/1.0
	* - OpenSSL license : https://www.openssl.org/source/license.html
	* - Apache 2.0 : http://www.apache.org/licenses/LICENSE-2.0
	*
	* More information about the BLAKE2 hash function can be found at
	* https://blake2.net.
	*
	* Note: the original sources have been modified for inclusion in linux kernel
	* in terms of coding style, using generic helpers and simplifications of error
	* handling.
	*/

	#include <asm/unaligned.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/kernel.h>
	#include <linux/bitops.h>
	#include <crypto/internal/hash.h>

	#define BLAKE2B_160_DIGEST_SIZE (160 / 8)
	#define BLAKE2B_256_DIGEST_SIZE (256 / 8)
	#define BLAKE2B_384_DIGEST_SIZE (384 / 8)
	#define BLAKE2B_512_DIGEST_SIZE (512 / 8)

	enum blake2b_constant {
	BLAKE2B_BLOCKBYTES = 128,
	BLAKE2B_OUTBYTES = 64,
	BLAKE2B_KEYBYTES = 64,
	BLAKE2B_SALTBYTES = 16,
	BLAKE2B_PERSONALBYTES = 16
	};

	struct blake2b_state {
	u64 h[8];
	u64 t[2];
	u64 f[2];
	u8 buf[BLAKE2B_BLOCKBYTES];
	size_t buflen;
	size_t outlen;
	u8 last_node;
	};

	struct blake2b_param {
	u8 digest_length; /* 1 */
	u8 key_length; /* 2 */
	u8 fanout; /* 3 */
	u8 depth; /* 4 */
	__le32 leaf_length; /* 8 */
	__le32 node_offset; /* 12 */
	__le32 xof_length; /* 16 */
	u8 node_depth; /* 17 */
	u8 inner_length; /* 18 */
	u8 reserved[14]; /* 32 */
	u8 salt[BLAKE2B_SALTBYTES]; /* 48 */
	u8 personal[BLAKE2B_PERSONALBYTES]; /* 64 */
	} __packed;

	static const u64 blake2b_IV[8] = {
	0x6a09e667f3bcc908ULL, 0xbb67ae8584caa73bULL,
	0x3c6ef372fe94f82bULL, 0xa54ff53a5f1d36f1ULL,
	0x510e527fade682d1ULL, 0x9b05688c2b3e6c1fULL,
	0x1f83d9abfb41bd6bULL, 0x5be0cd19137e2179ULL
	};

	static const u8 blake2b_sigma[12][16] = {
	{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
	{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
	{ 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
	{ 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
	{ 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
	{ 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
	{ 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
	{ 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
	{ 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
	{ 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 },
	{ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
	{ 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }
	};

	static void blake2b_update(struct blake2b_state S, const void pin, size_t inlen);

	static void blake2b_set_lastnode(struct blake2b_state *S)
	{
	S->f[1] = (u64)-1;
	}

	static void blake2b_set_lastblock(struct blake2b_state *S)
	{
	if (S->last_node)
	blake2b_set_lastnode(S);

	S->f[0] = (u64)-1;
	}

	static void blake2b_increment_counter(struct blake2b_state *S, const u64 inc)
	{
	S->t[0] += inc;
	S->t[1] += (S->t[0] < inc);
	}

	static void blake2b_init0(struct blake2b_state *S)
	{
	size_t i;

	memset(S, 0, sizeof(struct blake2b_state));

	for (i = 0; i < 8; ++i)
	S->h[i] = blake2b_IV[i];
	}

	/* init xors IV with input parameter block */
	static void blake2b_init_param(struct blake2b_state *S,
	const struct blake2b_param *P)
	{
	const u8 p = (const u8 )(P);
	size_t i;

	blake2b_init0(S);

	/* IV XOR ParamBlock */
	for (i = 0; i < 8; ++i)
	S->h[i] ^= get_unaligned_le64(p + sizeof(S->h[i]) * i);

	S->outlen = P->digest_length;
	}

	static void blake2b_init(struct blake2b_state *S, size_t outlen)
	{
	struct blake2b_param P;

	P.digest_length = (u8)outlen;
	P.key_length = 0;
	P.fanout = 1;
	P.depth = 1;
	P.leaf_length = 0;
	P.node_offset = 0;
	P.xof_length = 0;
	P.node_depth = 0;
	P.inner_length = 0;
	memset(P.reserved, 0, sizeof(P.reserved));
	memset(P.salt, 0, sizeof(P.salt));
	memset(P.personal, 0, sizeof(P.personal));
	blake2b_init_param(S, &P);
	}

	static void blake2b_init_key(struct blake2b_state *S, size_t outlen,
	const void *key, size_t keylen)
	{
	struct blake2b_param P;

	P.digest_length = (u8)outlen;
	P.key_length = (u8)keylen;
	P.fanout = 1;
	P.depth = 1;
	P.leaf_length = 0;
	P.node_offset = 0;
	P.xof_length = 0;
	P.node_depth = 0;
	P.inner_length = 0;
	memset(P.reserved, 0, sizeof(P.reserved));
	memset(P.salt, 0, sizeof(P.salt));
	memset(P.personal, 0, sizeof(P.personal));

	blake2b_init_param(S, &P);

	{
	u8 block[BLAKE2B_BLOCKBYTES];

	memset(block, 0, BLAKE2B_BLOCKBYTES);
	memcpy(block, key, keylen);
	blake2b_update(S, block, BLAKE2B_BLOCKBYTES);
	memzero_explicit(block, BLAKE2B_BLOCKBYTES);
	}
	}

	#define G(r,i,a,b,c,d) \
	do { \
	a = a + b + m[blake2b_sigma[r][2*i+0]]; \
	d = ror64(d ^ a, 32); \
	c = c + d; \
	b = ror64(b ^ c, 24); \
	a = a + b + m[blake2b_sigma[r][2*i+1]]; \
	d = ror64(d ^ a, 16); \
	c = c + d; \
	b = ror64(b ^ c, 63); \
	} while (0)

	#define ROUND(r) \
	do { \
	G(r,0,v[ 0],v[ 4],v[ 8],v[12]); \
	G(r,1,v[ 1],v[ 5],v[ 9],v[13]); \
	G(r,2,v[ 2],v[ 6],v[10],v[14]); \
	G(r,3,v[ 3],v[ 7],v[11],v[15]); \
	G(r,4,v[ 0],v[ 5],v[10],v[15]); \
	G(r,5,v[ 1],v[ 6],v[11],v[12]); \
	G(r,6,v[ 2],v[ 7],v[ 8],v[13]); \
	G(r,7,v[ 3],v[ 4],v[ 9],v[14]); \
	} while (0)

	static void blake2b_compress(struct blake2b_state *S,
	const u8 block[BLAKE2B_BLOCKBYTES])
	{
	u64 m[16];
	u64 v[16];
	size_t i;

	for (i = 0; i < 16; ++i)
	m[i] = get_unaligned_le64(block + i * sizeof(m[i]));

	for (i = 0; i < 8; ++i)
	v[i] = S->h[i];

	v[ 8] = blake2b_IV[0];
	v[ 9] = blake2b_IV[1];
	v[10] = blake2b_IV[2];
	v[11] = blake2b_IV[3];
	v[12] = blake2b_IV[4] ^ S->t[0];
	v[13] = blake2b_IV[5] ^ S->t[1];
	v[14] = blake2b_IV[6] ^ S->f[0];
	v[15] = blake2b_IV[7] ^ S->f[1];

	ROUND(0);
	ROUND(1);
	ROUND(2);
	ROUND(3);
	ROUND(4);
	ROUND(5);
	ROUND(6);
	ROUND(7);
	ROUND(8);
	ROUND(9);
	ROUND(10);
	ROUND(11);

	for (i = 0; i < 8; ++i)
	S->h[i] = S->h[i] ^ v[i] ^ v[i + 8];
	}

	#undef G
	#undef ROUND

	static void blake2b_update(struct blake2b_state S, const void pin, size_t inlen)
	{
	const u8 in = (const u8 )pin;

	if (inlen > 0) {
	size_t left = S->buflen;
	size_t fill = BLAKE2B_BLOCKBYTES - left;

	if (inlen > fill) {
	S->buflen = 0;
	/* Fill buffer */
	memcpy(S->buf + left, in, fill);
	blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
	/* Compress */
	blake2b_compress(S, S->buf);
	in += fill;
	inlen -= fill;
	while (inlen > BLAKE2B_BLOCKBYTES) {
	blake2b_increment_counter(S, BLAKE2B_BLOCKBYTES);
	blake2b_compress(S, in);
	in += BLAKE2B_BLOCKBYTES;
	inlen -= BLAKE2B_BLOCKBYTES;
	}
	}
	memcpy(S->buf + S->buflen, in, inlen);
	S->buflen += inlen;
	}
	}

	static void blake2b_final(struct blake2b_state S, void out, size_t outlen)
	{
	u8 buffer[BLAKE2B_OUTBYTES] = {0};
	size_t i;

	blake2b_increment_counter(S, S->buflen);
	blake2b_set_lastblock(S);
	/* Padding */
	memset(S->buf + S->buflen, 0, BLAKE2B_BLOCKBYTES - S->buflen);
	blake2b_compress(S, S->buf);

	/* Output full hash to temp buffer */
	for (i = 0; i < 8; ++i)
	put_unaligned_le64(S->h[i], buffer + sizeof(S->h[i]) * i);

	memcpy(out, buffer, S->outlen);
	memzero_explicit(buffer, sizeof(buffer));
	}

	struct digest_tfm_ctx {
	u8 key[BLAKE2B_KEYBYTES];
	unsigned int keylen;
	};

	static int digest_setkey(struct crypto_shash tfm, const u8 key,
	unsigned int keylen)
	{
	struct digest_tfm_ctx *mctx = crypto_shash_ctx(tfm);

	if (keylen == 0 \|\| keylen > BLAKE2B_KEYBYTES) {
	crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
	return -EINVAL;
	}

	memcpy(mctx->key, key, keylen);
	mctx->keylen = keylen;

	return 0;
	}

	static int digest_init(struct shash_desc *desc)
	{
	struct digest_tfm_ctx *mctx = crypto_shash_ctx(desc->tfm);
	struct blake2b_state *state = shash_desc_ctx(desc);
	const int digestsize = crypto_shash_digestsize(desc->tfm);

	if (mctx->keylen == 0)
	blake2b_init(state, digestsize);
	else
	blake2b_init_key(state, digestsize, mctx->key, mctx->keylen);
	return 0;
	}

	static int digest_update(struct shash_desc desc, const u8 data,
	unsigned int length)
	{
	struct blake2b_state *state = shash_desc_ctx(desc);

	blake2b_update(state, data, length);
	return 0;
	}

	static int digest_final(struct shash_desc desc, u8 out)
	{
	struct blake2b_state *state = shash_desc_ctx(desc);
	const int digestsize = crypto_shash_digestsize(desc->tfm);

	blake2b_final(state, out, digestsize);
	return 0;
	}

	static struct shash_alg blake2b_algs[] = {
	{
	.base.cra_name = "blake2b-160",
	.base.cra_driver_name = "blake2b-160-generic",
	.base.cra_priority = 100,
	.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
	.base.cra_blocksize = BLAKE2B_BLOCKBYTES,
	.base.cra_ctxsize = sizeof(struct digest_tfm_ctx),
	.base.cra_module = THIS_MODULE,
	.digestsize = BLAKE2B_160_DIGEST_SIZE,
	.setkey = digest_setkey,
	.init = digest_init,
	.update = digest_update,
	.final = digest_final,
	.descsize = sizeof(struct blake2b_state),
	}, {
	.base.cra_name = "blake2b-256",
	.base.cra_driver_name = "blake2b-256-generic",
	.base.cra_priority = 100,
	.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
	.base.cra_blocksize = BLAKE2B_BLOCKBYTES,
	.base.cra_ctxsize = sizeof(struct digest_tfm_ctx),
	.base.cra_module = THIS_MODULE,
	.digestsize = BLAKE2B_256_DIGEST_SIZE,
	.setkey = digest_setkey,
	.init = digest_init,
	.update = digest_update,
	.final = digest_final,
	.descsize = sizeof(struct blake2b_state),
	}, {
	.base.cra_name = "blake2b-384",
	.base.cra_driver_name = "blake2b-384-generic",
	.base.cra_priority = 100,
	.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
	.base.cra_blocksize = BLAKE2B_BLOCKBYTES,
	.base.cra_ctxsize = sizeof(struct digest_tfm_ctx),
	.base.cra_module = THIS_MODULE,
	.digestsize = BLAKE2B_384_DIGEST_SIZE,
	.setkey = digest_setkey,
	.init = digest_init,
	.update = digest_update,
	.final = digest_final,
	.descsize = sizeof(struct blake2b_state),
	}, {
	.base.cra_name = "blake2b-512",
	.base.cra_driver_name = "blake2b-512-generic",
	.base.cra_priority = 100,
	.base.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
	.base.cra_blocksize = BLAKE2B_BLOCKBYTES,
	.base.cra_ctxsize = sizeof(struct digest_tfm_ctx),
	.base.cra_module = THIS_MODULE,
	.digestsize = BLAKE2B_512_DIGEST_SIZE,
	.setkey = digest_setkey,
	.init = digest_init,
	.update = digest_update,
	.final = digest_final,
	.descsize = sizeof(struct blake2b_state),
	}
	};

	static int __init blake2b_mod_init(void)
	{
	BUILD_BUG_ON(sizeof(struct blake2b_param) != BLAKE2B_OUTBYTES);

	return crypto_register_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs));
	}

	static void __exit blake2b_mod_fini(void)
	{
	crypto_unregister_shashes(blake2b_algs, ARRAY_SIZE(blake2b_algs));
	}

	subsys_initcall(blake2b_mod_init);
	module_exit(blake2b_mod_fini);

	MODULE_AUTHOR("David Sterba <kdave@kernel.org>");
	MODULE_DESCRIPTION("BLAKE2b generic implementation");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS_CRYPTO("blake2b-160");
	MODULE_ALIAS_CRYPTO("blake2b-160-generic");
	MODULE_ALIAS_CRYPTO("blake2b-256");
	MODULE_ALIAS_CRYPTO("blake2b-256-generic");
	MODULE_ALIAS_CRYPTO("blake2b-384");
	MODULE_ALIAS_CRYPTO("blake2b-384-generic");
	MODULE_ALIAS_CRYPTO("blake2b-512");
	MODULE_ALIAS_CRYPTO("blake2b-512-generic");