[git/git.git] / block-sha1 / sha1.c

/*
 * Based on the Mozilla SHA1 (see mozilla-sha1/sha1.c),
 * optimized to do word accesses rather than byte accesses,
 * and to avoid unnecessary copies into the context array.
 */

#include <string.h>
#include <arpa/inet.h>

#include "sha1.h"

/* Hash one 64-byte block of data */
static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data);

void blk_SHA1_Init(blk_SHA_CTX *ctx)
{
	ctx->lenW = 0;
	ctx->size = 0;

	/* Initialize H with the magic constants (see FIPS180 for constants)
	 */
	ctx->H[0] = 0x67452301;
	ctx->H[1] = 0xefcdab89;
	ctx->H[2] = 0x98badcfe;
	ctx->H[3] = 0x10325476;
	ctx->H[4] = 0xc3d2e1f0;
}


void blk_SHA1_Update(blk_SHA_CTX *ctx, const void *data, unsigned long len)
{
	int lenW = ctx->lenW;

	ctx->size += (unsigned long long) len << 3;

	/* Read the data into W and process blocks as they get full
	 */
	if (lenW) {
		int left = 64 - lenW;
		if (len < left)
			left = len;
		memcpy(lenW + (char *)ctx->W, data, left);
		lenW = (lenW + left) & 63;
		len -= left;
		data += left;
		ctx->lenW = lenW;
		if (lenW)
			return;
		blk_SHA1Block(ctx, ctx->W);
	}
	while (len >= 64) {
		blk_SHA1Block(ctx, data);
		data += 64;
		len -= 64;
	}
	if (len) {
		memcpy(ctx->W, data, len);
		ctx->lenW = len;
	}
}


void blk_SHA1_Final(unsigned char hashout[20], blk_SHA_CTX *ctx)
{
	static const unsigned char pad[64] = { 0x80 };
	unsigned int padlen[2];
	int i;

	/* Pad with a binary 1 (ie 0x80), then zeroes, then length
	 */
	padlen[0] = htonl(ctx->size >> 32);
	padlen[1] = htonl(ctx->size);

	blk_SHA1_Update(ctx, pad, 1+ (63 & (55 - ctx->lenW)));
	blk_SHA1_Update(ctx, padlen, 8);

	/* Output hash
	 */
	for (i = 0; i < 5; i++)
		((unsigned int *)hashout)[i] = htonl(ctx->H[i]);
}

#if defined(__i386__) || defined(__x86_64__)

#define SHA_ASM(op, x, n) ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; })
#define SHA_ROL(x,n)	SHA_ASM("rol", x, n)
#define SHA_ROR(x,n)	SHA_ASM("ror", x, n)

#else

#define SHA_ROT(X,l,r)	(((X) << (l)) | ((X) >> (r)))
#define SHA_ROL(X,n)	SHA_ROT(X,n,32-(n))
#define SHA_ROR(X,n)	SHA_ROT(X,32-(n),n)

#endif

static void blk_SHA1Block(blk_SHA_CTX *ctx, const unsigned int *data)
{
	unsigned int A,B,C,D,E,TEMP;
	unsigned int array[16];

	A = ctx->H[0];
	B = ctx->H[1];
	C = ctx->H[2];
	D = ctx->H[3];
	E = ctx->H[4];

#define T_0_15(t) \
	TEMP = htonl(data[t]); array[t] = TEMP; \
	TEMP += SHA_ROL(A,5) + (((C^D)&B)^D) + E + 0x5a827999; \
	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP; \

	T_0_15( 0); T_0_15( 1); T_0_15( 2); T_0_15( 3); T_0_15( 4);
	T_0_15( 5); T_0_15( 6); T_0_15( 7); T_0_15( 8); T_0_15( 9);
	T_0_15(10); T_0_15(11); T_0_15(12); T_0_15(13); T_0_15(14);
	T_0_15(15);

/* This "rolls" over the 512-bit array */
#define W(x) (array[(x)&15])
#define SHA_XOR(t) \
	TEMP = SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1); W(t) = TEMP;

#define T_16_19(t) \
	SHA_XOR(t); \
	TEMP += SHA_ROL(A,5) + (((C^D)&B)^D) + E + 0x5a827999; \
	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP; \

	T_16_19(16); T_16_19(17); T_16_19(18); T_16_19(19);

#define T_20_39(t) \
	SHA_XOR(t); \
	TEMP += SHA_ROL(A,5) + (B^C^D) + E + 0x6ed9eba1; \
	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;

	T_20_39(20); T_20_39(21); T_20_39(22); T_20_39(23); T_20_39(24);
	T_20_39(25); T_20_39(26); T_20_39(27); T_20_39(28); T_20_39(29);
	T_20_39(30); T_20_39(31); T_20_39(32); T_20_39(33); T_20_39(34);
	T_20_39(35); T_20_39(36); T_20_39(37); T_20_39(38); T_20_39(39);

#define T_40_59(t) \
	SHA_XOR(t); \
	TEMP += SHA_ROL(A,5) + ((B&C)|(D&(B|C))) + E + 0x8f1bbcdc; \
	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;

	T_40_59(40); T_40_59(41); T_40_59(42); T_40_59(43); T_40_59(44);
	T_40_59(45); T_40_59(46); T_40_59(47); T_40_59(48); T_40_59(49);
	T_40_59(50); T_40_59(51); T_40_59(52); T_40_59(53); T_40_59(54);
	T_40_59(55); T_40_59(56); T_40_59(57); T_40_59(58); T_40_59(59);

#define T_60_79(t) \
	SHA_XOR(t); \
	TEMP += SHA_ROL(A,5) + (B^C^D) + E + 0xca62c1d6; \
	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;

	T_60_79(60); T_60_79(61); T_60_79(62); T_60_79(63); T_60_79(64);
	T_60_79(65); T_60_79(66); T_60_79(67); T_60_79(68); T_60_79(69);
	T_60_79(70); T_60_79(71); T_60_79(72); T_60_79(73); T_60_79(74);
	T_60_79(75); T_60_79(76); T_60_79(77); T_60_79(78); T_60_79(79);

	ctx->H[0] += A;
	ctx->H[1] += B;
	ctx->H[2] += C;
	ctx->H[3] += D;
	ctx->H[4] += E;
}
Commit	Line	Data
d7c208a9 LT	1	/*
	2	* Based on the Mozilla SHA1 (see mozilla-sha1/sha1.c),
	3	* optimized to do word accesses rather than byte accesses,
	4	* and to avoid unnecessary copies into the context array.
	5	*/
	6
	7	#include <string.h>
	8	#include <arpa/inet.h>
	9
	10	#include "sha1.h"
	11
	12	/* Hash one 64-byte block of data */
	13	static void blk_SHA1Block(blk_SHA_CTX ctx, const unsigned int data);
	14
	15	void blk_SHA1_Init(blk_SHA_CTX *ctx)
	16	{
	17	ctx->lenW = 0;
	18	ctx->size = 0;
	19
	20	/* Initialize H with the magic constants (see FIPS180 for constants)
	21	*/
	22	ctx->H[0] = 0x67452301;
	23	ctx->H[1] = 0xefcdab89;
	24	ctx->H[2] = 0x98badcfe;
	25	ctx->H[3] = 0x10325476;
	26	ctx->H[4] = 0xc3d2e1f0;
	27	}
	28
	29
	30	void blk_SHA1_Update(blk_SHA_CTX ctx, const void data, unsigned long len)
	31	{
	32	int lenW = ctx->lenW;
	33
b26a9d50	34	ctx->size += (unsigned long long) len << 3;
d7c208a9 LT	35
	36	/* Read the data into W and process blocks as they get full
	37	*/
	38	if (lenW) {
	39	int left = 64 - lenW;
	40	if (len < left)
	41	left = len;
	42	memcpy(lenW + (char *)ctx->W, data, left);
	43	lenW = (lenW + left) & 63;
	44	len -= left;
	45	data += left;
	46	ctx->lenW = lenW;
	47	if (lenW)
	48	return;
	49	blk_SHA1Block(ctx, ctx->W);
	50	}
	51	while (len >= 64) {
	52	blk_SHA1Block(ctx, data);
	53	data += 64;
	54	len -= 64;
	55	}
	56	if (len) {
	57	memcpy(ctx->W, data, len);
	58	ctx->lenW = len;
	59	}
	60	}
	61
	62
	63	void blk_SHA1_Final(unsigned char hashout[20], blk_SHA_CTX *ctx)
	64	{
	65	static const unsigned char pad[64] = { 0x80 };
	66	unsigned int padlen[2];
	67	int i;
	68
	69	/* Pad with a binary 1 (ie 0x80), then zeroes, then length
	70	*/
b26a9d50 JH	71	padlen[0] = htonl(ctx->size >> 32);
b26a9d50 JH	72	padlen[1] = htonl(ctx->size);
d7c208a9 LT	73
	74	blk_SHA1_Update(ctx, pad, 1+ (63 & (55 - ctx->lenW)));
	75	blk_SHA1_Update(ctx, padlen, 8);
	76
	77	/* Output hash
	78	*/
	79	for (i = 0; i < 5; i++)
	80	((unsigned int *)hashout)[i] = htonl(ctx->H[i]);
	81	}
	82
b8e48a89 LT	83	#if defined(__i386__) \|\| defined(__x86_64__)
b8e48a89 LT	84
fd536d34	85	#define SHA_ASM(op, x, n) ({ unsigned int __res; __asm__(op " %1,%0":"=r" (__res):"i" (n), "0" (x)); __res; })
b8e48a89 LT	86	#define SHA_ROL(x,n) SHA_ASM("rol", x, n)
	87	#define SHA_ROR(x,n) SHA_ASM("ror", x, n)
	88
	89	#else
	90
fd536d34	91	#define SHA_ROT(X,l,r) (((X) << (l)) \| ((X) >> (r)))
b8e48a89 LT	92	#define SHA_ROL(X,n) SHA_ROT(X,n,32-(n))
	93	#define SHA_ROR(X,n) SHA_ROT(X,32-(n),n)
	94
	95	#endif
d7c208a9 LT	96
	97	static void blk_SHA1Block(blk_SHA_CTX ctx, const unsigned int data)
	98	{
d7c208a9	99	unsigned int A,B,C,D,E,TEMP;
7b5075fc	100	unsigned int array[16];
d7c208a9	101
d7c208a9 LT	102	A = ctx->H[0];
	103	B = ctx->H[1];
	104	C = ctx->H[2];
	105	D = ctx->H[3];
	106	E = ctx->H[4];
	107
139e3456	108	#define T_0_15(t) \
7b5075fc LT	109	TEMP = htonl(data[t]); array[t] = TEMP; \
7b5075fc LT	110	TEMP += SHA_ROL(A,5) + (((C^D)&B)^D) + E + 0x5a827999; \
139e3456 LT	111	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP; \
	112
	113	T_0_15( 0); T_0_15( 1); T_0_15( 2); T_0_15( 3); T_0_15( 4);
	114	T_0_15( 5); T_0_15( 6); T_0_15( 7); T_0_15( 8); T_0_15( 9);
	115	T_0_15(10); T_0_15(11); T_0_15(12); T_0_15(13); T_0_15(14);
	116	T_0_15(15);
	117
7b5075fc LT	118	/* This "rolls" over the 512-bit array */
	119	#define W(x) (array[(x)&15])
	120	#define SHA_XOR(t) \
	121	TEMP = SHA_ROL(W(t+13) ^ W(t+8) ^ W(t+2) ^ W(t), 1); W(t) = TEMP;
139e3456 LT	122
139e3456 LT	123	#define T_16_19(t) \
7b5075fc LT	124	SHA_XOR(t); \
	125	TEMP += SHA_ROL(A,5) + (((C^D)&B)^D) + E + 0x5a827999; \
	126	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP; \
d7c208a9	127
139e3456	128	T_16_19(16); T_16_19(17); T_16_19(18); T_16_19(19);
d7c208a9 LT	129
d7c208a9 LT	130	#define T_20_39(t) \
7b5075fc LT	131	SHA_XOR(t); \
7b5075fc LT	132	TEMP += SHA_ROL(A,5) + (B^C^D) + E + 0x6ed9eba1; \
b8e48a89	133	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;
d7c208a9 LT	134
	135	T_20_39(20); T_20_39(21); T_20_39(22); T_20_39(23); T_20_39(24);
	136	T_20_39(25); T_20_39(26); T_20_39(27); T_20_39(28); T_20_39(29);
	137	T_20_39(30); T_20_39(31); T_20_39(32); T_20_39(33); T_20_39(34);
	138	T_20_39(35); T_20_39(36); T_20_39(37); T_20_39(38); T_20_39(39);
	139
	140	#define T_40_59(t) \
7b5075fc LT	141	SHA_XOR(t); \
7b5075fc LT	142	TEMP += SHA_ROL(A,5) + ((B&C)\|(D&(B\|C))) + E + 0x8f1bbcdc; \
b8e48a89	143	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;
d7c208a9 LT	144
	145	T_40_59(40); T_40_59(41); T_40_59(42); T_40_59(43); T_40_59(44);
	146	T_40_59(45); T_40_59(46); T_40_59(47); T_40_59(48); T_40_59(49);
	147	T_40_59(50); T_40_59(51); T_40_59(52); T_40_59(53); T_40_59(54);
	148	T_40_59(55); T_40_59(56); T_40_59(57); T_40_59(58); T_40_59(59);
	149
	150	#define T_60_79(t) \
7b5075fc LT	151	SHA_XOR(t); \
7b5075fc LT	152	TEMP += SHA_ROL(A,5) + (B^C^D) + E + 0xca62c1d6; \
b8e48a89	153	E = D; D = C; C = SHA_ROR(B, 2); B = A; A = TEMP;
d7c208a9 LT	154
	155	T_60_79(60); T_60_79(61); T_60_79(62); T_60_79(63); T_60_79(64);
	156	T_60_79(65); T_60_79(66); T_60_79(67); T_60_79(68); T_60_79(69);
	157	T_60_79(70); T_60_79(71); T_60_79(72); T_60_79(73); T_60_79(74);
	158	T_60_79(75); T_60_79(76); T_60_79(77); T_60_79(78); T_60_79(79);
	159
	160	ctx->H[0] += A;
	161	ctx->H[1] += B;
	162	ctx->H[2] += C;
	163	ctx->H[3] += D;
	164	ctx->H[4] += E;
	165	}