[J-u-boot.git] / lib / sha256.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * FIPS-180-2 compliant SHA-256 implementation
 *
 * Copyright (C) 2001-2003  Christophe Devine
 */

#ifndef USE_HOSTCC
#include <common.h>
#include <linux/string.h>
#else
#include <string.h>
#endif /* USE_HOSTCC */
#include <watchdog.h>
#include <u-boot/sha256.h>

const uint8_t sha256_der_prefix[SHA256_DER_LEN] = {
	0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86,
	0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05,
	0x00, 0x04, 0x20
};

/*
 * 32-bit integer manipulation macros (big endian)
 */
#ifndef GET_UINT32_BE
#define GET_UINT32_BE(n,b,i) {				\
	(n) = ( (unsigned long) (b)[(i)    ] << 24 )	\
	    | ( (unsigned long) (b)[(i) + 1] << 16 )	\
	    | ( (unsigned long) (b)[(i) + 2] <<  8 )	\
	    | ( (unsigned long) (b)[(i) + 3]       );	\
}
#endif
#ifndef PUT_UINT32_BE
#define PUT_UINT32_BE(n,b,i) {				\
	(b)[(i)    ] = (unsigned char) ( (n) >> 24 );	\
	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 );	\
	(b)[(i) + 2] = (unsigned char) ( (n) >>  8 );	\
	(b)[(i) + 3] = (unsigned char) ( (n)       );	\
}
#endif

void sha256_starts(sha256_context * ctx)
{
	ctx->total[0] = 0;
	ctx->total[1] = 0;

	ctx->state[0] = 0x6A09E667;
	ctx->state[1] = 0xBB67AE85;
	ctx->state[2] = 0x3C6EF372;
	ctx->state[3] = 0xA54FF53A;
	ctx->state[4] = 0x510E527F;
	ctx->state[5] = 0x9B05688C;
	ctx->state[6] = 0x1F83D9AB;
	ctx->state[7] = 0x5BE0CD19;
}

static void sha256_process(sha256_context *ctx, const uint8_t data[64])
{
	uint32_t temp1, temp2;
	uint32_t W[64];
	uint32_t A, B, C, D, E, F, G, H;

	GET_UINT32_BE(W[0], data, 0);
	GET_UINT32_BE(W[1], data, 4);
	GET_UINT32_BE(W[2], data, 8);
	GET_UINT32_BE(W[3], data, 12);
	GET_UINT32_BE(W[4], data, 16);
	GET_UINT32_BE(W[5], data, 20);
	GET_UINT32_BE(W[6], data, 24);
	GET_UINT32_BE(W[7], data, 28);
	GET_UINT32_BE(W[8], data, 32);
	GET_UINT32_BE(W[9], data, 36);
	GET_UINT32_BE(W[10], data, 40);
	GET_UINT32_BE(W[11], data, 44);
	GET_UINT32_BE(W[12], data, 48);
	GET_UINT32_BE(W[13], data, 52);
	GET_UINT32_BE(W[14], data, 56);
	GET_UINT32_BE(W[15], data, 60);

#define SHR(x,n) ((x & 0xFFFFFFFF) >> n)
#define ROTR(x,n) (SHR(x,n) | (x << (32 - n)))

#define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^ SHR(x, 3))
#define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^ SHR(x,10))

#define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
#define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))

#define F0(x,y,z) ((x & y) | (z & (x | y)))
#define F1(x,y,z) (z ^ (x & (y ^ z)))

#define R(t)					\
(						\
	W[t] = S1(W[t - 2]) + W[t - 7] +	\
		S0(W[t - 15]) + W[t - 16]	\
)

#define P(a,b,c,d,e,f,g,h,x,K) {		\
	temp1 = h + S3(e) + F1(e,f,g) + K + x;	\
	temp2 = S2(a) + F0(a,b,c);		\
	d += temp1; h = temp1 + temp2;		\
}

	A = ctx->state[0];
	B = ctx->state[1];
	C = ctx->state[2];
	D = ctx->state[3];
	E = ctx->state[4];
	F = ctx->state[5];
	G = ctx->state[6];
	H = ctx->state[7];

	P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
	P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
	P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
	P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
	P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
	P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
	P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
	P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
	P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
	P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
	P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
	P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
	P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
	P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
	P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
	P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
	P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
	P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
	P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
	P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
	P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
	P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
	P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
	P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
	P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
	P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
	P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
	P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
	P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
	P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
	P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
	P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
	P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
	P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
	P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
	P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
	P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
	P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
	P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
	P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
	P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
	P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
	P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
	P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
	P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
	P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
	P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
	P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
	P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
	P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
	P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
	P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
	P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
	P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
	P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
	P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
	P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
	P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
	P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
	P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
	P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
	P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
	P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
	P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);

	ctx->state[0] += A;
	ctx->state[1] += B;
	ctx->state[2] += C;
	ctx->state[3] += D;
	ctx->state[4] += E;
	ctx->state[5] += F;
	ctx->state[6] += G;
	ctx->state[7] += H;
}

void sha256_update(sha256_context *ctx, const uint8_t *input, uint32_t length)
{
	uint32_t left, fill;

	if (!length)
		return;

	left = ctx->total[0] & 0x3F;
	fill = 64 - left;

	ctx->total[0] += length;
	ctx->total[0] &= 0xFFFFFFFF;

	if (ctx->total[0] < length)
		ctx->total[1]++;

	if (left && length >= fill) {
		memcpy((void *) (ctx->buffer + left), (void *) input, fill);
		sha256_process(ctx, ctx->buffer);
		length -= fill;
		input += fill;
		left = 0;
	}

	while (length >= 64) {
		sha256_process(ctx, input);
		length -= 64;
		input += 64;
	}

	if (length)
		memcpy((void *) (ctx->buffer + left), (void *) input, length);
}

static uint8_t sha256_padding[64] = {
	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	   0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
};

void sha256_finish(sha256_context * ctx, uint8_t digest[32])
{
	uint32_t last, padn;
	uint32_t high, low;
	uint8_t msglen[8];

	high = ((ctx->total[0] >> 29)
		| (ctx->total[1] << 3));
	low = (ctx->total[0] << 3);

	PUT_UINT32_BE(high, msglen, 0);
	PUT_UINT32_BE(low, msglen, 4);

	last = ctx->total[0] & 0x3F;
	padn = (last < 56) ? (56 - last) : (120 - last);

	sha256_update(ctx, sha256_padding, padn);
	sha256_update(ctx, msglen, 8);

	PUT_UINT32_BE(ctx->state[0], digest, 0);
	PUT_UINT32_BE(ctx->state[1], digest, 4);
	PUT_UINT32_BE(ctx->state[2], digest, 8);
	PUT_UINT32_BE(ctx->state[3], digest, 12);
	PUT_UINT32_BE(ctx->state[4], digest, 16);
	PUT_UINT32_BE(ctx->state[5], digest, 20);
	PUT_UINT32_BE(ctx->state[6], digest, 24);
	PUT_UINT32_BE(ctx->state[7], digest, 28);
}

/*
 * Output = SHA-256( input buffer ). Trigger the watchdog every 'chunk_sz'
 * bytes of input processed.
 */
void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
		unsigned char *output, unsigned int chunk_sz)
{
	sha256_context ctx;
#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
	const unsigned char *end;
	unsigned char *curr;
	int chunk;
#endif

	sha256_starts(&ctx);

#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
	curr = (unsigned char *)input;
	end = input + ilen;
	while (curr < end) {
		chunk = end - curr;
		if (chunk > chunk_sz)
			chunk = chunk_sz;
		sha256_update(&ctx, curr, chunk);
		curr += chunk;
		WATCHDOG_RESET();
	}
#else
	sha256_update(&ctx, input, ilen);
#endif

	sha256_finish(&ctx, output);
}
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
b571afde JCPV	2	/*
	3	* FIPS-180-2 compliant SHA-256 implementation
	4	*
	5	* Copyright (C) 2001-2003 Christophe Devine
b571afde JCPV	6	*/
	7
	8	#ifndef USE_HOSTCC
	9	#include <common.h>
822ef00e AB	10	#include <linux/string.h>
	11	#else
	12	#include <string.h>
b571afde JCPV	13	#endif /* USE_HOSTCC */
b571afde JCPV	14	#include <watchdog.h>
2b9912e6	15	#include <u-boot/sha256.h>
b571afde	16
da29f299 AD	17	const uint8_t sha256_der_prefix[SHA256_DER_LEN] = {
	18	0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86,
	19	0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05,
	20	0x00, 0x04, 0x20
	21	};
	22
b571afde JCPV	23	/*
	24	* 32-bit integer manipulation macros (big endian)
	25	*/
	26	#ifndef GET_UINT32_BE
	27	#define GET_UINT32_BE(n,b,i) { \
	28	(n) = ( (unsigned long) (b)[(i) ] << 24 ) \
	29	\| ( (unsigned long) (b)[(i) + 1] << 16 ) \
	30	\| ( (unsigned long) (b)[(i) + 2] << 8 ) \
	31	\| ( (unsigned long) (b)[(i) + 3] ); \
	32	}
	33	#endif
	34	#ifndef PUT_UINT32_BE
	35	#define PUT_UINT32_BE(n,b,i) { \
	36	(b)[(i) ] = (unsigned char) ( (n) >> 24 ); \
	37	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 ); \
	38	(b)[(i) + 2] = (unsigned char) ( (n) >> 8 ); \
	39	(b)[(i) + 3] = (unsigned char) ( (n) ); \
	40	}
	41	#endif
	42
	43	void sha256_starts(sha256_context * ctx)
	44	{
	45	ctx->total[0] = 0;
	46	ctx->total[1] = 0;
	47
	48	ctx->state[0] = 0x6A09E667;
	49	ctx->state[1] = 0xBB67AE85;
	50	ctx->state[2] = 0x3C6EF372;
	51	ctx->state[3] = 0xA54FF53A;
	52	ctx->state[4] = 0x510E527F;
	53	ctx->state[5] = 0x9B05688C;
	54	ctx->state[6] = 0x1F83D9AB;
	55	ctx->state[7] = 0x5BE0CD19;
	56	}
	57
ec7381fb	58	static void sha256_process(sha256_context *ctx, const uint8_t data[64])
b571afde JCPV	59	{
	60	uint32_t temp1, temp2;
	61	uint32_t W[64];
	62	uint32_t A, B, C, D, E, F, G, H;
	63
	64	GET_UINT32_BE(W[0], data, 0);
	65	GET_UINT32_BE(W[1], data, 4);
	66	GET_UINT32_BE(W[2], data, 8);
	67	GET_UINT32_BE(W[3], data, 12);
	68	GET_UINT32_BE(W[4], data, 16);
	69	GET_UINT32_BE(W[5], data, 20);
	70	GET_UINT32_BE(W[6], data, 24);
	71	GET_UINT32_BE(W[7], data, 28);
	72	GET_UINT32_BE(W[8], data, 32);
	73	GET_UINT32_BE(W[9], data, 36);
	74	GET_UINT32_BE(W[10], data, 40);
	75	GET_UINT32_BE(W[11], data, 44);
	76	GET_UINT32_BE(W[12], data, 48);
	77	GET_UINT32_BE(W[13], data, 52);
	78	GET_UINT32_BE(W[14], data, 56);
	79	GET_UINT32_BE(W[15], data, 60);
	80
	81	#define SHR(x,n) ((x & 0xFFFFFFFF) >> n)
	82	#define ROTR(x,n) (SHR(x,n) \| (x << (32 - n)))
	83
	84	#define S0(x) (ROTR(x, 7) ^ ROTR(x,18) ^ SHR(x, 3))
	85	#define S1(x) (ROTR(x,17) ^ ROTR(x,19) ^ SHR(x,10))
	86
	87	#define S2(x) (ROTR(x, 2) ^ ROTR(x,13) ^ ROTR(x,22))
	88	#define S3(x) (ROTR(x, 6) ^ ROTR(x,11) ^ ROTR(x,25))
	89
	90	#define F0(x,y,z) ((x & y) \| (z & (x \| y)))
	91	#define F1(x,y,z) (z ^ (x & (y ^ z)))
	92
	93	#define R(t) \
	94	( \
	95	W[t] = S1(W[t - 2]) + W[t - 7] + \
	96	S0(W[t - 15]) + W[t - 16] \
	97	)
	98
	99	#define P(a,b,c,d,e,f,g,h,x,K) { \
	100	temp1 = h + S3(e) + F1(e,f,g) + K + x; \
	101	temp2 = S2(a) + F0(a,b,c); \
	102	d += temp1; h = temp1 + temp2; \
	103	}
	104
	105	A = ctx->state[0];
	106	B = ctx->state[1];
	107	C = ctx->state[2];
	108	D = ctx->state[3];
	109	E = ctx->state[4];
	110	F = ctx->state[5];
	111	G = ctx->state[6];
	112	H = ctx->state[7];
	113
	114	P(A, B, C, D, E, F, G, H, W[0], 0x428A2F98);
	115	P(H, A, B, C, D, E, F, G, W[1], 0x71374491);
	116	P(G, H, A, B, C, D, E, F, W[2], 0xB5C0FBCF);
	117	P(F, G, H, A, B, C, D, E, W[3], 0xE9B5DBA5);
	118	P(E, F, G, H, A, B, C, D, W[4], 0x3956C25B);
	119	P(D, E, F, G, H, A, B, C, W[5], 0x59F111F1);
	120	P(C, D, E, F, G, H, A, B, W[6], 0x923F82A4);
	121	P(B, C, D, E, F, G, H, A, W[7], 0xAB1C5ED5);
	122	P(A, B, C, D, E, F, G, H, W[8], 0xD807AA98);
123	P(H, A, B, C, D, E, F, G, W[9], 0x12835B01);
124	P(G, H, A, B, C, D, E, F, W[10], 0x243185BE);
125	P(F, G, H, A, B, C, D, E, W[11], 0x550C7DC3);
126	P(E, F, G, H, A, B, C, D, W[12], 0x72BE5D74);
127	P(D, E, F, G, H, A, B, C, W[13], 0x80DEB1FE);
128	P(C, D, E, F, G, H, A, B, W[14], 0x9BDC06A7);
129	P(B, C, D, E, F, G, H, A, W[15], 0xC19BF174);
130	P(A, B, C, D, E, F, G, H, R(16), 0xE49B69C1);
131	P(H, A, B, C, D, E, F, G, R(17), 0xEFBE4786);
132	P(G, H, A, B, C, D, E, F, R(18), 0x0FC19DC6);
133	P(F, G, H, A, B, C, D, E, R(19), 0x240CA1CC);
134	P(E, F, G, H, A, B, C, D, R(20), 0x2DE92C6F);
135	P(D, E, F, G, H, A, B, C, R(21), 0x4A7484AA);
136	P(C, D, E, F, G, H, A, B, R(22), 0x5CB0A9DC);
137	P(B, C, D, E, F, G, H, A, R(23), 0x76F988DA);
138	P(A, B, C, D, E, F, G, H, R(24), 0x983E5152);
139	P(H, A, B, C, D, E, F, G, R(25), 0xA831C66D);
140	P(G, H, A, B, C, D, E, F, R(26), 0xB00327C8);
141	P(F, G, H, A, B, C, D, E, R(27), 0xBF597FC7);
142	P(E, F, G, H, A, B, C, D, R(28), 0xC6E00BF3);
143	P(D, E, F, G, H, A, B, C, R(29), 0xD5A79147);
144	P(C, D, E, F, G, H, A, B, R(30), 0x06CA6351);
145	P(B, C, D, E, F, G, H, A, R(31), 0x14292967);
146	P(A, B, C, D, E, F, G, H, R(32), 0x27B70A85);
147	P(H, A, B, C, D, E, F, G, R(33), 0x2E1B2138);
148	P(G, H, A, B, C, D, E, F, R(34), 0x4D2C6DFC);
149	P(F, G, H, A, B, C, D, E, R(35), 0x53380D13);
150	P(E, F, G, H, A, B, C, D, R(36), 0x650A7354);
151	P(D, E, F, G, H, A, B, C, R(37), 0x766A0ABB);
152	P(C, D, E, F, G, H, A, B, R(38), 0x81C2C92E);
153	P(B, C, D, E, F, G, H, A, R(39), 0x92722C85);
154	P(A, B, C, D, E, F, G, H, R(40), 0xA2BFE8A1);
155	P(H, A, B, C, D, E, F, G, R(41), 0xA81A664B);
156	P(G, H, A, B, C, D, E, F, R(42), 0xC24B8B70);
157	P(F, G, H, A, B, C, D, E, R(43), 0xC76C51A3);
158	P(E, F, G, H, A, B, C, D, R(44), 0xD192E819);
159	P(D, E, F, G, H, A, B, C, R(45), 0xD6990624);
160	P(C, D, E, F, G, H, A, B, R(46), 0xF40E3585);
161	P(B, C, D, E, F, G, H, A, R(47), 0x106AA070);
162	P(A, B, C, D, E, F, G, H, R(48), 0x19A4C116);
163	P(H, A, B, C, D, E, F, G, R(49), 0x1E376C08);
164	P(G, H, A, B, C, D, E, F, R(50), 0x2748774C);
165	P(F, G, H, A, B, C, D, E, R(51), 0x34B0BCB5);
166	P(E, F, G, H, A, B, C, D, R(52), 0x391C0CB3);
167	P(D, E, F, G, H, A, B, C, R(53), 0x4ED8AA4A);
168	P(C, D, E, F, G, H, A, B, R(54), 0x5B9CCA4F);
169	P(B, C, D, E, F, G, H, A, R(55), 0x682E6FF3);
170	P(A, B, C, D, E, F, G, H, R(56), 0x748F82EE);
171	P(H, A, B, C, D, E, F, G, R(57), 0x78A5636F);
172	P(G, H, A, B, C, D, E, F, R(58), 0x84C87814);
173	P(F, G, H, A, B, C, D, E, R(59), 0x8CC70208);
174	P(E, F, G, H, A, B, C, D, R(60), 0x90BEFFFA);
175	P(D, E, F, G, H, A, B, C, R(61), 0xA4506CEB);
176	P(C, D, E, F, G, H, A, B, R(62), 0xBEF9A3F7);
177	P(B, C, D, E, F, G, H, A, R(63), 0xC67178F2);
178
179	ctx->state[0] += A;
180	ctx->state[1] += B;
181	ctx->state[2] += C;
182	ctx->state[3] += D;
183	ctx->state[4] += E;
184	ctx->state[5] += F;
185	ctx->state[6] += G;
186	ctx->state[7] += H;
187	}
188
ec7381fb	189	void sha256_update(sha256_context ctx, const uint8_t input, uint32_t length)
b571afde JCPV	190	{
	191	uint32_t left, fill;
	192
	193	if (!length)
	194	return;
	195
	196	left = ctx->total[0] & 0x3F;
	197	fill = 64 - left;
	198
	199	ctx->total[0] += length;
	200	ctx->total[0] &= 0xFFFFFFFF;
	201
	202	if (ctx->total[0] < length)
	203	ctx->total[1]++;
	204
	205	if (left && length >= fill) {
	206	memcpy((void ) (ctx->buffer + left), (void ) input, fill);
	207	sha256_process(ctx, ctx->buffer);
	208	length -= fill;
	209	input += fill;
	210	left = 0;
	211	}
	212
	213	while (length >= 64) {
	214	sha256_process(ctx, input);
	215	length -= 64;
	216	input += 64;
	217	}
	218
	219	if (length)
	220	memcpy((void ) (ctx->buffer + left), (void ) input, length);
	221	}
	222
	223	static uint8_t sha256_padding[64] = {
	224	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	225	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	226	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	227	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
	228	};
	229
	230	void sha256_finish(sha256_context * ctx, uint8_t digest[32])
	231	{
	232	uint32_t last, padn;
	233	uint32_t high, low;
	234	uint8_t msglen[8];
	235
	236	high = ((ctx->total[0] >> 29)
	237	\| (ctx->total[1] << 3));
	238	low = (ctx->total[0] << 3);
	239
	240	PUT_UINT32_BE(high, msglen, 0);
	241	PUT_UINT32_BE(low, msglen, 4);
	242
	243	last = ctx->total[0] & 0x3F;
	244	padn = (last < 56) ? (56 - last) : (120 - last);
	245
	246	sha256_update(ctx, sha256_padding, padn);
	247	sha256_update(ctx, msglen, 8);
	248
	249	PUT_UINT32_BE(ctx->state[0], digest, 0);
	250	PUT_UINT32_BE(ctx->state[1], digest, 4);
	251	PUT_UINT32_BE(ctx->state[2], digest, 8);
	252	PUT_UINT32_BE(ctx->state[3], digest, 12);
	253	PUT_UINT32_BE(ctx->state[4], digest, 16);
254	PUT_UINT32_BE(ctx->state[5], digest, 20);
255	PUT_UINT32_BE(ctx->state[6], digest, 24);
256	PUT_UINT32_BE(ctx->state[7], digest, 28);
257	}
ec7381fb SG	258
	259	/*
	260	* Output = SHA-256( input buffer ). Trigger the watchdog every 'chunk_sz'
	261	* bytes of input processed.
	262	*/
	263	void sha256_csum_wd(const unsigned char *input, unsigned int ilen,
	264	unsigned char *output, unsigned int chunk_sz)
	265	{
	266	sha256_context ctx;
	267	#if defined(CONFIG_HW_WATCHDOG) \|\| defined(CONFIG_WATCHDOG)
2842c1c2 HS	268	const unsigned char *end;
2842c1c2 HS	269	unsigned char *curr;
ec7381fb SG	270	int chunk;
	271	#endif
	272
	273	sha256_starts(&ctx);
	274
	275	#if defined(CONFIG_HW_WATCHDOG) \|\| defined(CONFIG_WATCHDOG)
2842c1c2	276	curr = (unsigned char *)input;
ec7381fb SG	277	end = input + ilen;
	278	while (curr < end) {
	279	chunk = end - curr;
	280	if (chunk > chunk_sz)
	281	chunk = chunk_sz;
	282	sha256_update(&ctx, curr, chunk);
	283	curr += chunk;
	284	WATCHDOG_RESET();
	285	}
	286	#else
	287	sha256_update(&ctx, input, ilen);
	288	#endif
	289
	290	sha256_finish(&ctx, output);
	291	}