lib/crypto/sha256.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * SHA-256, as specified in
  * http://csrc.nist.gov/groups/STM/cavp/documents/shs/sha256-384-512.pdf
  *
  * SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>.
  *
  * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
  * Copyright (c) 2014 Red Hat Inc.
  */

 #include <linux/bitops.h>
 #include <linux/export.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <crypto/sha.h>
 #include <asm/unaligned.h>

 static inline u32 Ch(u32 x, u32 y, u32 z)
 {
 	return z ^ (x & (y ^ z));
 }

 static inline u32 Maj(u32 x, u32 y, u32 z)
 {
 	return (x & y) | (z & (x | y));
 }

 #define e0(x)       (ror32(x, 2) ^ ror32(x, 13) ^ ror32(x, 22))
 #define e1(x)       (ror32(x, 6) ^ ror32(x, 11) ^ ror32(x, 25))
 #define s0(x)       (ror32(x, 7) ^ ror32(x, 18) ^ (x >> 3))
 #define s1(x)       (ror32(x, 17) ^ ror32(x, 19) ^ (x >> 10))

 static inline void LOAD_OP(int I, u32 *W, const u8 *input)
 {
 	W[I] = get_unaligned_be32((__u32 *)input + I);
 }

 static inline void BLEND_OP(int I, u32 *W)
 {
 	W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
 }

 static void sha256_transform(u32 *state, const u8 *input)
 {
 	u32 a, b, c, d, e, f, g, h, t1, t2;
 	u32 W[64];
 	int i;

 	/* load the input */
 	for (i = 0; i < 16; i++)
 		LOAD_OP(i, W, input);

 	/* now blend */
 	for (i = 16; i < 64; i++)
 		BLEND_OP(i, W);

 	/* load the state into our registers */
 	a = state[0];  b = state[1];  c = state[2];  d = state[3];
 	e = state[4];  f = state[5];  g = state[6];  h = state[7];

 	/* now iterate */
 	t1 = h + e1(e) + Ch(e, f, g) + 0x428a2f98 + W[0];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0x71374491 + W[1];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0xb5c0fbcf + W[2];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0xe9b5dba5 + W[3];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x3956c25b + W[4];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0x59f111f1 + W[5];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x923f82a4 + W[6];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0xab1c5ed5 + W[7];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0xd807aa98 + W[8];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0x12835b01 + W[9];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0x243185be + W[10];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0x550c7dc3 + W[11];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x72be5d74 + W[12];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0x80deb1fe + W[13];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x9bdc06a7 + W[14];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0xc19bf174 + W[15];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0xe49b69c1 + W[16];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0xefbe4786 + W[17];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0x0fc19dc6 + W[18];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0x240ca1cc + W[19];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x2de92c6f + W[20];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0x4a7484aa + W[21];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x5cb0a9dc + W[22];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0x76f988da + W[23];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0x983e5152 + W[24];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0xa831c66d + W[25];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0xb00327c8 + W[26];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0xbf597fc7 + W[27];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0xc6e00bf3 + W[28];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0xd5a79147 + W[29];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x06ca6351 + W[30];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0x14292967 + W[31];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0x27b70a85 + W[32];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0x2e1b2138 + W[33];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0x4d2c6dfc + W[34];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0x53380d13 + W[35];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x650a7354 + W[36];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0x766a0abb + W[37];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x81c2c92e + W[38];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0x92722c85 + W[39];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0xa2bfe8a1 + W[40];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0xa81a664b + W[41];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0xc24b8b70 + W[42];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0xc76c51a3 + W[43];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0xd192e819 + W[44];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0xd6990624 + W[45];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0xf40e3585 + W[46];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0x106aa070 + W[47];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0x19a4c116 + W[48];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0x1e376c08 + W[49];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0x2748774c + W[50];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0x34b0bcb5 + W[51];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x391c0cb3 + W[52];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0x4ed8aa4a + W[53];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0x5b9cca4f + W[54];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0x682e6ff3 + W[55];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	t1 = h + e1(e) + Ch(e, f, g) + 0x748f82ee + W[56];
 	t2 = e0(a) + Maj(a, b, c);    d += t1;    h = t1 + t2;
 	t1 = g + e1(d) + Ch(d, e, f) + 0x78a5636f + W[57];
 	t2 = e0(h) + Maj(h, a, b);    c += t1;    g = t1 + t2;
 	t1 = f + e1(c) + Ch(c, d, e) + 0x84c87814 + W[58];
 	t2 = e0(g) + Maj(g, h, a);    b += t1;    f = t1 + t2;
 	t1 = e + e1(b) + Ch(b, c, d) + 0x8cc70208 + W[59];
 	t2 = e0(f) + Maj(f, g, h);    a += t1;    e = t1 + t2;
 	t1 = d + e1(a) + Ch(a, b, c) + 0x90befffa + W[60];
 	t2 = e0(e) + Maj(e, f, g);    h += t1;    d = t1 + t2;
 	t1 = c + e1(h) + Ch(h, a, b) + 0xa4506ceb + W[61];
 	t2 = e0(d) + Maj(d, e, f);    g += t1;    c = t1 + t2;
 	t1 = b + e1(g) + Ch(g, h, a) + 0xbef9a3f7 + W[62];
 	t2 = e0(c) + Maj(c, d, e);    f += t1;    b = t1 + t2;
 	t1 = a + e1(f) + Ch(f, g, h) + 0xc67178f2 + W[63];
 	t2 = e0(b) + Maj(b, c, d);    e += t1;    a = t1 + t2;

 	state[0] += a; state[1] += b; state[2] += c; state[3] += d;
 	state[4] += e; state[5] += f; state[6] += g; state[7] += h;

 	/* clear any sensitive info... */
 	a = b = c = d = e = f = g = h = t1 = t2 = 0;
 	memzero_explicit(W, 64 * sizeof(u32));
 }

 void sha256_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
 {
 	unsigned int partial, done;
 	const u8 *src;

 	partial = sctx->count & 0x3f;
 	sctx->count += len;
 	done = 0;
 	src = data;

 	if ((partial + len) > 63) {
 		if (partial) {
 			done = -partial;
 			memcpy(sctx->buf + partial, data, done + 64);
 			src = sctx->buf;
 		}

 		do {
 			sha256_transform(sctx->state, src);
 			done += 64;
 			src = data + done;
 		} while (done + 63 < len);

 		partial = 0;
 	}
 	memcpy(sctx->buf + partial, src, len - done);
 }
 EXPORT_SYMBOL(sha256_update);

 void sha224_update(struct sha256_state *sctx, const u8 *data, unsigned int len)
 {
 	sha256_update(sctx, data, len);
 }
 EXPORT_SYMBOL(sha224_update);

 static void __sha256_final(struct sha256_state *sctx, u8 *out, int digest_words)
 {
 	__be32 *dst = (__be32 *)out;
 	__be64 bits;
 	unsigned int index, pad_len;
 	int i;
 	static const u8 padding[64] = { 0x80, };

 	/* Save number of bits */
 	bits = cpu_to_be64(sctx->count << 3);

 	/* Pad out to 56 mod 64. */
 	index = sctx->count & 0x3f;
 	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
 	sha256_update(sctx, padding, pad_len);

 	/* Append length (before padding) */
 	sha256_update(sctx, (const u8 *)&bits, sizeof(bits));

 	/* Store state in digest */
 	for (i = 0; i < digest_words; i++)
 		put_unaligned_be32(sctx->state[i], &dst[i]);

 	/* Zeroize sensitive information. */
 	memset(sctx, 0, sizeof(*sctx));
 }

 void sha256_final(struct sha256_state *sctx, u8 *out)
 {
 	__sha256_final(sctx, out, 8);
 }
 EXPORT_SYMBOL(sha256_final);

 void sha224_final(struct sha256_state *sctx, u8 *out)
 {
 	__sha256_final(sctx, out, 7);
 }
 EXPORT_SYMBOL(sha224_final);

 void sha256(const u8 *data, unsigned int len, u8 *out)
 {
 	struct sha256_state sctx;

 	sha256_init(&sctx);
 	sha256_update(&sctx, data, len);
 	sha256_final(&sctx, out);
 }
 EXPORT_SYMBOL(sha256);

 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* SHA-256, as specified in
	* http://csrc.nist.gov/groups/STM/cavp/documents/shs/sha256-384-512.pdf
	*
	* SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>.
	*
	* Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
	* Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
	* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
	* Copyright (c) 2014 Red Hat Inc.
	*/

	#include <linux/bitops.h>
	#include <linux/export.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <crypto/sha.h>
	#include <asm/unaligned.h>

	static inline u32 Ch(u32 x, u32 y, u32 z)
	{
	return z ^ (x & (y ^ z));
	}

	static inline u32 Maj(u32 x, u32 y, u32 z)
	{
	return (x & y) \| (z & (x \| y));
	}

	#define e0(x) (ror32(x, 2) ^ ror32(x, 13) ^ ror32(x, 22))
	#define e1(x) (ror32(x, 6) ^ ror32(x, 11) ^ ror32(x, 25))
	#define s0(x) (ror32(x, 7) ^ ror32(x, 18) ^ (x >> 3))
	#define s1(x) (ror32(x, 17) ^ ror32(x, 19) ^ (x >> 10))

	static inline void LOAD_OP(int I, u32 W, const u8 input)
	{
	W[I] = get_unaligned_be32((__u32 *)input + I);
	}

	static inline void BLEND_OP(int I, u32 *W)
	{
	W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16];
	}

	static void sha256_transform(u32 state, const u8 input)
	{
	u32 a, b, c, d, e, f, g, h, t1, t2;
	u32 W[64];
	int i;

	/* load the input */
	for (i = 0; i < 16; i++)
	LOAD_OP(i, W, input);

	/* now blend */
	for (i = 16; i < 64; i++)
	BLEND_OP(i, W);

	/* load the state into our registers */
	a = state[0]; b = state[1]; c = state[2]; d = state[3];
	e = state[4]; f = state[5]; g = state[6]; h = state[7];

	/* now iterate */
	t1 = h + e1(e) + Ch(e, f, g) + 0x428a2f98 + W[0];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0x71374491 + W[1];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0xb5c0fbcf + W[2];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0xe9b5dba5 + W[3];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x3956c25b + W[4];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0x59f111f1 + W[5];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x923f82a4 + W[6];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0xab1c5ed5 + W[7];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0xd807aa98 + W[8];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0x12835b01 + W[9];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0x243185be + W[10];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0x550c7dc3 + W[11];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x72be5d74 + W[12];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0x80deb1fe + W[13];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x9bdc06a7 + W[14];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0xc19bf174 + W[15];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0xe49b69c1 + W[16];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0xefbe4786 + W[17];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0x0fc19dc6 + W[18];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0x240ca1cc + W[19];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x2de92c6f + W[20];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0x4a7484aa + W[21];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x5cb0a9dc + W[22];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0x76f988da + W[23];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0x983e5152 + W[24];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0xa831c66d + W[25];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0xb00327c8 + W[26];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0xbf597fc7 + W[27];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0xc6e00bf3 + W[28];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0xd5a79147 + W[29];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x06ca6351 + W[30];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0x14292967 + W[31];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0x27b70a85 + W[32];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0x2e1b2138 + W[33];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0x4d2c6dfc + W[34];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0x53380d13 + W[35];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x650a7354 + W[36];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0x766a0abb + W[37];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x81c2c92e + W[38];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0x92722c85 + W[39];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0xa2bfe8a1 + W[40];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0xa81a664b + W[41];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0xc24b8b70 + W[42];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0xc76c51a3 + W[43];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0xd192e819 + W[44];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0xd6990624 + W[45];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0xf40e3585 + W[46];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0x106aa070 + W[47];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0x19a4c116 + W[48];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0x1e376c08 + W[49];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0x2748774c + W[50];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0x34b0bcb5 + W[51];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x391c0cb3 + W[52];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0x4ed8aa4a + W[53];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0x5b9cca4f + W[54];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0x682e6ff3 + W[55];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	t1 = h + e1(e) + Ch(e, f, g) + 0x748f82ee + W[56];
	t2 = e0(a) + Maj(a, b, c); d += t1; h = t1 + t2;
	t1 = g + e1(d) + Ch(d, e, f) + 0x78a5636f + W[57];
	t2 = e0(h) + Maj(h, a, b); c += t1; g = t1 + t2;
	t1 = f + e1(c) + Ch(c, d, e) + 0x84c87814 + W[58];
	t2 = e0(g) + Maj(g, h, a); b += t1; f = t1 + t2;
	t1 = e + e1(b) + Ch(b, c, d) + 0x8cc70208 + W[59];
	t2 = e0(f) + Maj(f, g, h); a += t1; e = t1 + t2;
	t1 = d + e1(a) + Ch(a, b, c) + 0x90befffa + W[60];
	t2 = e0(e) + Maj(e, f, g); h += t1; d = t1 + t2;
	t1 = c + e1(h) + Ch(h, a, b) + 0xa4506ceb + W[61];
	t2 = e0(d) + Maj(d, e, f); g += t1; c = t1 + t2;
	t1 = b + e1(g) + Ch(g, h, a) + 0xbef9a3f7 + W[62];
	t2 = e0(c) + Maj(c, d, e); f += t1; b = t1 + t2;
	t1 = a + e1(f) + Ch(f, g, h) + 0xc67178f2 + W[63];
	t2 = e0(b) + Maj(b, c, d); e += t1; a = t1 + t2;

	state[0] += a; state[1] += b; state[2] += c; state[3] += d;
	state[4] += e; state[5] += f; state[6] += g; state[7] += h;

	/* clear any sensitive info... */
	a = b = c = d = e = f = g = h = t1 = t2 = 0;
	memzero_explicit(W, 64 * sizeof(u32));
	}

	void sha256_update(struct sha256_state sctx, const u8 data, unsigned int len)
	{
	unsigned int partial, done;
	const u8 *src;

	partial = sctx->count & 0x3f;
	sctx->count += len;
	done = 0;
	src = data;

	if ((partial + len) > 63) {
	if (partial) {
	done = -partial;
	memcpy(sctx->buf + partial, data, done + 64);
	src = sctx->buf;
	}

	do {
	sha256_transform(sctx->state, src);
	done += 64;
	src = data + done;
	} while (done + 63 < len);

	partial = 0;
	}
	memcpy(sctx->buf + partial, src, len - done);
	}
	EXPORT_SYMBOL(sha256_update);

	void sha224_update(struct sha256_state sctx, const u8 data, unsigned int len)
	{
	sha256_update(sctx, data, len);
	}
	EXPORT_SYMBOL(sha224_update);

	static void __sha256_final(struct sha256_state sctx, u8 out, int digest_words)
	{
	__be32 dst = (__be32 )out;
	__be64 bits;
	unsigned int index, pad_len;
	int i;
	static const u8 padding[64] = { 0x80, };

	/* Save number of bits */
	bits = cpu_to_be64(sctx->count << 3);

	/* Pad out to 56 mod 64. */
	index = sctx->count & 0x3f;
	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
	sha256_update(sctx, padding, pad_len);

	/* Append length (before padding) */
	sha256_update(sctx, (const u8 *)&bits, sizeof(bits));

	/* Store state in digest */
	for (i = 0; i < digest_words; i++)
	put_unaligned_be32(sctx->state[i], &dst[i]);

	/* Zeroize sensitive information. */
	memset(sctx, 0, sizeof(*sctx));
	}

	void sha256_final(struct sha256_state sctx, u8 out)
	{
	__sha256_final(sctx, out, 8);
	}
	EXPORT_SYMBOL(sha256_final);

	void sha224_final(struct sha256_state sctx, u8 out)
	{
	__sha256_final(sctx, out, 7);
	}
	EXPORT_SYMBOL(sha224_final);

	void sha256(const u8 data, unsigned int len, u8 out)
	{
	struct sha256_state sctx;

	sha256_init(&sctx);
	sha256_update(&sctx, data, len);
	sha256_final(&sctx, out);
	}
	EXPORT_SYMBOL(sha256);

	MODULE_LICENSE("GPL");