summaryrefslogtreecommitdiff
path: root/Utilities/cmlibrhash/librhash/sha256.c
blob: 21a69aae238e932da9b0348f384ccf284eb470db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
/* sha256.c - an implementation of SHA-256/224 hash functions
 * based on FIPS 180-3 (Federal Information Processing Standart).
 *
 * Copyright (c) 2010, Aleksey Kravchenko <rhash.admin@gmail.com>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE  INCLUDING ALL IMPLIED WARRANTIES OF  MERCHANTABILITY
 * AND FITNESS.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT,  OR CONSEQUENTIAL DAMAGES  OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE,  DATA OR PROFITS,  WHETHER IN AN ACTION OF CONTRACT,  NEGLIGENCE
 * OR OTHER TORTIOUS ACTION,  ARISING OUT OF  OR IN CONNECTION  WITH THE USE  OR
 * PERFORMANCE OF THIS SOFTWARE.
 */

#include <string.h>
#include "byte_order.h"
#include "sha256.h"

/* SHA-224 and SHA-256 constants for 64 rounds. These words represent
 * the first 32 bits of the fractional parts of the cube
 * roots of the first 64 prime numbers. */
static const unsigned rhash_k256[64] = {
	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1,
	0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
	0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786,
	0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147,
	0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
	0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b,
	0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a,
	0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
	0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
};

/* The SHA256/224 functions defined by FIPS 180-3, 4.1.2 */
/* Optimized version of Ch(x,y,z)=((x & y) | (~x & z)) */
#define Ch(x,y,z)  ((z) ^ ((x) & ((y) ^ (z))))
/* Optimized version of Maj(x,y,z)=((x & y) ^ (x & z) ^ (y & z)) */
#define Maj(x,y,z) (((x) & (y)) ^ ((z) & ((x) ^ (y))))

#define Sigma0(x) (ROTR32((x), 2) ^ ROTR32((x), 13) ^ ROTR32((x), 22))
#define Sigma1(x) (ROTR32((x), 6) ^ ROTR32((x), 11) ^ ROTR32((x), 25))
#define sigma0(x) (ROTR32((x), 7) ^ ROTR32((x), 18) ^ ((x) >>  3))
#define sigma1(x) (ROTR32((x),17) ^ ROTR32((x), 19) ^ ((x) >> 10))

/* Recalculate element n-th of circular buffer W using formula
 *   W[n] = sigma1(W[n - 2]) + W[n - 7] + sigma0(W[n - 15]) + W[n - 16]; */
#define RECALCULATE_W(W,n) (W[n] += \
	(sigma1(W[(n - 2) & 15]) + W[(n - 7) & 15] + sigma0(W[(n - 15) & 15])))

#define ROUND(a,b,c,d,e,f,g,h,k,data) { \
	unsigned T1 = h + Sigma1(e) + Ch(e,f,g) + k + (data); \
	d += T1, h = T1 + Sigma0(a) + Maj(a,b,c); }
#define ROUND_1_16(a,b,c,d,e,f,g,h,n) \
	ROUND(a,b,c,d,e,f,g,h, rhash_k256[n], W[n] = be2me_32(block[n]))
#define ROUND_17_64(a,b,c,d,e,f,g,h,n) \
	ROUND(a,b,c,d,e,f,g,h, k[n], RECALCULATE_W(W, n))

/**
 * Initialize context before calculaing hash.
 *
 * @param ctx context to initialize
 */
void rhash_sha256_init(sha256_ctx* ctx)
{
	/* Initial values. These words were obtained by taking the first 32
	 * bits of the fractional parts of the square roots of the first
	 * eight prime numbers. */
	static const unsigned SHA256_H0[8] = {
		0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
		0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
	};

	ctx->length = 0;
	ctx->digest_length = sha256_hash_size;

	/* initialize algorithm state */
	memcpy(ctx->hash, SHA256_H0, sizeof(ctx->hash));
}

/**
 * Initialize context before calculaing hash.
 *
 * @param ctx context to initialize
 */
void rhash_sha224_init(struct sha256_ctx* ctx)
{
	/* Initial values from FIPS 180-3. These words were obtained by taking
	 * bits from 33th to 64th of the fractional parts of the square
	 * roots of ninth through sixteenth prime numbers. */
	static const unsigned SHA224_H0[8] = {
		0xc1059ed8, 0x367cd507, 0x3070dd17, 0xf70e5939,
		0xffc00b31, 0x68581511, 0x64f98fa7, 0xbefa4fa4
	};

	ctx->length = 0;
	ctx->digest_length = sha224_hash_size;

	memcpy(ctx->hash, SHA224_H0, sizeof(ctx->hash));
}

/**
 * The core transformation. Process a 512-bit block.
 *
 * @param hash algorithm state
 * @param block the message block to process
 */
static void rhash_sha256_process_block(unsigned hash[8], unsigned block[16])
{
	unsigned A, B, C, D, E, F, G, H;
	unsigned W[16];
	const unsigned* k;
	int i;

	A = hash[0], B = hash[1], C = hash[2], D = hash[3];
	E = hash[4], F = hash[5], G = hash[6], H = hash[7];

	/* Compute SHA using alternate Method: FIPS 180-3 6.1.3 */
	ROUND_1_16(A, B, C, D, E, F, G, H, 0);
	ROUND_1_16(H, A, B, C, D, E, F, G, 1);
	ROUND_1_16(G, H, A, B, C, D, E, F, 2);
	ROUND_1_16(F, G, H, A, B, C, D, E, 3);
	ROUND_1_16(E, F, G, H, A, B, C, D, 4);
	ROUND_1_16(D, E, F, G, H, A, B, C, 5);
	ROUND_1_16(C, D, E, F, G, H, A, B, 6);
	ROUND_1_16(B, C, D, E, F, G, H, A, 7);
	ROUND_1_16(A, B, C, D, E, F, G, H, 8);
	ROUND_1_16(H, A, B, C, D, E, F, G, 9);
	ROUND_1_16(G, H, A, B, C, D, E, F, 10);
	ROUND_1_16(F, G, H, A, B, C, D, E, 11);
	ROUND_1_16(E, F, G, H, A, B, C, D, 12);
	ROUND_1_16(D, E, F, G, H, A, B, C, 13);
	ROUND_1_16(C, D, E, F, G, H, A, B, 14);
	ROUND_1_16(B, C, D, E, F, G, H, A, 15);

	for (i = 16, k = &rhash_k256[16]; i < 64; i += 16, k += 16) {
		ROUND_17_64(A, B, C, D, E, F, G, H,  0);
		ROUND_17_64(H, A, B, C, D, E, F, G,  1);
		ROUND_17_64(G, H, A, B, C, D, E, F,  2);
		ROUND_17_64(F, G, H, A, B, C, D, E,  3);
		ROUND_17_64(E, F, G, H, A, B, C, D,  4);
		ROUND_17_64(D, E, F, G, H, A, B, C,  5);
		ROUND_17_64(C, D, E, F, G, H, A, B,  6);
		ROUND_17_64(B, C, D, E, F, G, H, A,  7);
		ROUND_17_64(A, B, C, D, E, F, G, H,  8);
		ROUND_17_64(H, A, B, C, D, E, F, G,  9);
		ROUND_17_64(G, H, A, B, C, D, E, F, 10);
		ROUND_17_64(F, G, H, A, B, C, D, E, 11);
		ROUND_17_64(E, F, G, H, A, B, C, D, 12);
		ROUND_17_64(D, E, F, G, H, A, B, C, 13);
		ROUND_17_64(C, D, E, F, G, H, A, B, 14);
		ROUND_17_64(B, C, D, E, F, G, H, A, 15);
	}

	hash[0] += A, hash[1] += B, hash[2] += C, hash[3] += D;
	hash[4] += E, hash[5] += F, hash[6] += G, hash[7] += H;
}

/**
 * Calculate message hash.
 * Can be called repeatedly with chunks of the message to be hashed.
 *
 * @param ctx the algorithm context containing current hashing state
 * @param msg message chunk
 * @param size length of the message chunk
 */
void rhash_sha256_update(sha256_ctx* ctx, const unsigned char* msg, size_t size)
{
	size_t index = (size_t)ctx->length & 63;
	ctx->length += size;

	/* fill partial block */
	if (index) {
		size_t left = sha256_block_size - index;
		memcpy((char*)ctx->message + index, msg, (size < left ? size : left));
		if (size < left) return;

		/* process partial block */
		rhash_sha256_process_block(ctx->hash, (unsigned*)ctx->message);
		msg  += left;
		size -= left;
	}
	while (size >= sha256_block_size) {
		unsigned* aligned_message_block;
		if (IS_ALIGNED_32(msg)) {
			/* the most common case is processing of an already aligned message
			without copying it */
			aligned_message_block = (unsigned*)msg;
		} else {
			memcpy(ctx->message, msg, sha256_block_size);
			aligned_message_block = (unsigned*)ctx->message;
		}

		rhash_sha256_process_block(ctx->hash, aligned_message_block);
		msg  += sha256_block_size;
		size -= sha256_block_size;
	}
	if (size) {
		memcpy(ctx->message, msg, size); /* save leftovers */
	}
}

/**
 * Store calculated hash into the given array.
 *
 * @param ctx the algorithm context containing current hashing state
 * @param result calculated hash in binary form
 */
void rhash_sha256_final(sha256_ctx* ctx, unsigned char* result)
{
	size_t index = ((unsigned)ctx->length & 63) >> 2;
	unsigned shift = ((unsigned)ctx->length & 3) * 8;

	/* pad message and run for last block */

	/* append the byte 0x80 to the message */
	ctx->message[index]   &= le2me_32(~(0xFFFFFFFFu << shift));
	ctx->message[index++] ^= le2me_32(0x80u << shift);

	/* if no room left in the message to store 64-bit message length */
	if (index > 14) {
		/* then fill the rest with zeros and process it */
		while (index < 16) {
			ctx->message[index++] = 0;
		}
		rhash_sha256_process_block(ctx->hash, ctx->message);
		index = 0;
	}
	while (index < 14) {
		ctx->message[index++] = 0;
	}
	ctx->message[14] = be2me_32( (unsigned)(ctx->length >> 29) );
	ctx->message[15] = be2me_32( (unsigned)(ctx->length << 3) );
	rhash_sha256_process_block(ctx->hash, ctx->message);

	if (result) be32_copy(result, 0, ctx->hash, ctx->digest_length);
}