xref: /freebsd/sys/cddl/boot/zfs/sha256.c (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /*
27  * Copyright 2013 Saso Kiselkov.  All rights reserved.
28  * Copyright 2015 Toomas Soome <tsoome@me.com>
29  */
30 
31 /*
32  * SHA-256 and SHA-512/256 hashes, as specified in FIPS 180-4, available at:
33  * http://csrc.nist.gov/cryptval
34  *
35  * This is a very compact implementation of SHA-256 and SHA-512/256.
36  * It is designed to be simple and portable, not to be fast.
37  */
38 
39 /*
40  * The literal definitions according to FIPS180-4 would be:
41  *
42  * 	Ch(x, y, z)     (((x) & (y)) ^ ((~(x)) & (z)))
43  * 	Maj(x, y, z)    (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
44  *
45  * We use logical equivalents which require one less op.
46  */
47 #define	Ch(x, y, z)	((z) ^ ((x) & ((y) ^ (z))))
48 #define	Maj(x, y, z)	(((x) & (y)) ^ ((z) & ((x) ^ (y))))
49 #define	ROTR(x, n)	(((x) >> (n)) | ((x) << ((sizeof (x) * NBBY)-(n))))
50 
51 /* SHA-224/256 operations */
52 #define	BIGSIGMA0_256(x)	(ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
53 #define	BIGSIGMA1_256(x)	(ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
54 #define	SIGMA0_256(x)		(ROTR(x, 7) ^ ROTR(x, 18) ^ ((x) >> 3))
55 #define	SIGMA1_256(x)		(ROTR(x, 17) ^ ROTR(x, 19) ^ ((x) >> 10))
56 
57 /* SHA-384/512 operations */
58 #define	BIGSIGMA0_512(x)	(ROTR((x), 28) ^ ROTR((x), 34) ^ ROTR((x), 39))
59 #define	BIGSIGMA1_512(x)	(ROTR((x), 14) ^ ROTR((x), 18) ^ ROTR((x), 41))
60 #define	SIGMA0_512(x)		(ROTR((x), 1) ^ ROTR((x), 8) ^ ((x) >> 7))
61 #define	SIGMA1_512(x)		(ROTR((x), 19) ^ ROTR((x), 61) ^ ((x) >> 6))
62 
63 /* SHA-256 round constants */
64 static const uint32_t SHA256_K[64] = {
65 	0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
66 	0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
67 	0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
68 	0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
69 	0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
70 	0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
71 	0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
72 	0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
73 	0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
74 	0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
75 	0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
76 	0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
77 	0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
78 	0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
79 	0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
80 	0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
81 };
82 
83 /* SHA-512 round constants */
84 static const uint64_t SHA512_K[80] = {
85 	0x428A2F98D728AE22ULL, 0x7137449123EF65CDULL,
86 	0xB5C0FBCFEC4D3B2FULL, 0xE9B5DBA58189DBBCULL,
87 	0x3956C25BF348B538ULL, 0x59F111F1B605D019ULL,
88 	0x923F82A4AF194F9BULL, 0xAB1C5ED5DA6D8118ULL,
89 	0xD807AA98A3030242ULL, 0x12835B0145706FBEULL,
90 	0x243185BE4EE4B28CULL, 0x550C7DC3D5FFB4E2ULL,
91 	0x72BE5D74F27B896FULL, 0x80DEB1FE3B1696B1ULL,
92 	0x9BDC06A725C71235ULL, 0xC19BF174CF692694ULL,
93 	0xE49B69C19EF14AD2ULL, 0xEFBE4786384F25E3ULL,
94 	0x0FC19DC68B8CD5B5ULL, 0x240CA1CC77AC9C65ULL,
95 	0x2DE92C6F592B0275ULL, 0x4A7484AA6EA6E483ULL,
96 	0x5CB0A9DCBD41FBD4ULL, 0x76F988DA831153B5ULL,
97 	0x983E5152EE66DFABULL, 0xA831C66D2DB43210ULL,
98 	0xB00327C898FB213FULL, 0xBF597FC7BEEF0EE4ULL,
99 	0xC6E00BF33DA88FC2ULL, 0xD5A79147930AA725ULL,
100 	0x06CA6351E003826FULL, 0x142929670A0E6E70ULL,
101 	0x27B70A8546D22FFCULL, 0x2E1B21385C26C926ULL,
102 	0x4D2C6DFC5AC42AEDULL, 0x53380D139D95B3DFULL,
103 	0x650A73548BAF63DEULL, 0x766A0ABB3C77B2A8ULL,
104 	0x81C2C92E47EDAEE6ULL, 0x92722C851482353BULL,
105 	0xA2BFE8A14CF10364ULL, 0xA81A664BBC423001ULL,
106 	0xC24B8B70D0F89791ULL, 0xC76C51A30654BE30ULL,
107 	0xD192E819D6EF5218ULL, 0xD69906245565A910ULL,
108 	0xF40E35855771202AULL, 0x106AA07032BBD1B8ULL,
109 	0x19A4C116B8D2D0C8ULL, 0x1E376C085141AB53ULL,
110 	0x2748774CDF8EEB99ULL, 0x34B0BCB5E19B48A8ULL,
111 	0x391C0CB3C5C95A63ULL, 0x4ED8AA4AE3418ACBULL,
112 	0x5B9CCA4F7763E373ULL, 0x682E6FF3D6B2B8A3ULL,
113 	0x748F82EE5DEFB2FCULL, 0x78A5636F43172F60ULL,
114 	0x84C87814A1F0AB72ULL, 0x8CC702081A6439ECULL,
115 	0x90BEFFFA23631E28ULL, 0xA4506CEBDE82BDE9ULL,
116 	0xBEF9A3F7B2C67915ULL, 0xC67178F2E372532BULL,
117 	0xCA273ECEEA26619CULL, 0xD186B8C721C0C207ULL,
118 	0xEADA7DD6CDE0EB1EULL, 0xF57D4F7FEE6ED178ULL,
119 	0x06F067AA72176FBAULL, 0x0A637DC5A2C898A6ULL,
120 	0x113F9804BEF90DAEULL, 0x1B710B35131C471BULL,
121 	0x28DB77F523047D84ULL, 0x32CAAB7B40C72493ULL,
122 	0x3C9EBE0A15C9BEBCULL, 0x431D67C49C100D4CULL,
123 	0x4CC5D4BECB3E42B6ULL, 0x597F299CFC657E2AULL,
124 	0x5FCB6FAB3AD6FAECULL, 0x6C44198C4A475817ULL
125 };
126 
127 static void
128 SHA256Transform(uint32_t *H, const uint8_t *cp)
129 {
130 	uint32_t a, b, c, d, e, f, g, h, t, T1, T2, W[64];
131 
132 	/* copy chunk into the first 16 words of the message schedule */
133 	for (t = 0; t < 16; t++, cp += sizeof (uint32_t))
134 		W[t] = (cp[0] << 24) | (cp[1] << 16) | (cp[2] << 8) | cp[3];
135 
136 	/* extend the first 16 words into the remaining 48 words */
137 	for (t = 16; t < 64; t++)
138 		W[t] = SIGMA1_256(W[t - 2]) + W[t - 7] +
139 		    SIGMA0_256(W[t - 15]) + W[t - 16];
140 
141 	/* init working variables to the current hash value */
142 	a = H[0]; b = H[1]; c = H[2]; d = H[3];
143 	e = H[4]; f = H[5]; g = H[6]; h = H[7];
144 
145 	/* iterate the compression function for all rounds of the hash */
146 	for (t = 0; t < 64; t++) {
147 		T1 = h + BIGSIGMA1_256(e) + Ch(e, f, g) + SHA256_K[t] + W[t];
148 		T2 = BIGSIGMA0_256(a) + Maj(a, b, c);
149 		h = g; g = f; f = e; e = d + T1;
150 		d = c; c = b; b = a; a = T1 + T2;
151 	}
152 
153 	/* add the compressed chunk to the current hash value */
154 	H[0] += a; H[1] += b; H[2] += c; H[3] += d;
155 	H[4] += e; H[5] += f; H[6] += g; H[7] += h;
156 }
157 
158 static void
159 SHA512Transform(uint64_t *H, const uint8_t *cp)
160 {
161 	uint64_t a, b, c, d, e, f, g, h, t, T1, T2, W[80];
162 
163 	/* copy chunk into the first 16 words of the message schedule */
164 	for (t = 0; t < 16; t++, cp += sizeof (uint64_t))
165 		W[t] = ((uint64_t)cp[0] << 56) | ((uint64_t)cp[1] << 48) |
166 		    ((uint64_t)cp[2] << 40) | ((uint64_t)cp[3] << 32) |
167 		    ((uint64_t)cp[4] << 24) | ((uint64_t)cp[5] << 16) |
168 		    ((uint64_t)cp[6] << 8) | (uint64_t)cp[7];
169 
170 	/* extend the first 16 words into the remaining 64 words */
171 	for (t = 16; t < 80; t++)
172 		W[t] = SIGMA1_512(W[t - 2]) + W[t - 7] +
173 		    SIGMA0_512(W[t - 15]) + W[t - 16];
174 
175 	/* init working variables to the current hash value */
176 	a = H[0]; b = H[1]; c = H[2]; d = H[3];
177 	e = H[4]; f = H[5]; g = H[6]; h = H[7];
178 
179 	/* iterate the compression function for all rounds of the hash */
180 	for (t = 0; t < 80; t++) {
181 		T1 = h + BIGSIGMA1_512(e) + Ch(e, f, g) + SHA512_K[t] + W[t];
182 		T2 = BIGSIGMA0_512(a) + Maj(a, b, c);
183 		h = g; g = f; f = e; e = d + T1;
184 		d = c; c = b; b = a; a = T1 + T2;
185 	}
186 
187 	/* add the compressed chunk to the current hash value */
188 	H[0] += a; H[1] += b; H[2] += c; H[3] += d;
189 	H[4] += e; H[5] += f; H[6] += g; H[7] += h;
190 }
191 
192 /*
193  * Implements the SHA-224 and SHA-256 hash algos - to select between them
194  * pass the appropriate initial values of 'H' and truncate the last 32 bits
195  * in case of SHA-224.
196  */
197 static void
198 SHA256(uint32_t *H, const void *buf, uint64_t size, zio_cksum_t *zcp)
199 {
200 	uint8_t pad[128];
201 	unsigned padsize = size & 63;
202 	unsigned i, k;
203 
204 	/* process all blocks up to the last one */
205 	for (i = 0; i < size - padsize; i += 64)
206 		SHA256Transform(H, (const uint8_t *)buf + i);
207 
208 	/* process the last block and padding */
209 	for (k = 0; k < padsize; k++)
210 		pad[k] = ((const uint8_t *)buf)[k + i];
211 
212 	for (pad[padsize++] = 0x80; (padsize & 63) != 56; padsize++)
213 		pad[padsize] = 0;
214 
215 	for (i = 0; i < 8; i++)
216 		pad[padsize++] = (size << 3) >> (56 - 8 * i);
217 
218 	for (i = 0; i < padsize; i += 64)
219 		SHA256Transform(H, pad + i);
220 
221 	ZIO_SET_CHECKSUM(zcp,
222 	    (uint64_t)H[0] << 32 | H[1],
223 	    (uint64_t)H[2] << 32 | H[3],
224 	    (uint64_t)H[4] << 32 | H[5],
225 	    (uint64_t)H[6] << 32 | H[7]);
226 }
227 
228 /*
229  * encode 64bit data in big-endian format.
230  */
231 static void
232 Encode64(uint8_t *output, uint64_t *input, size_t len)
233 {
234 	size_t i, j;
235 	for (i = 0, j = 0; j < len; i++, j += 8) {
236 		output[j]	= (input[i] >> 56) & 0xff;
237 		output[j + 1]	= (input[i] >> 48) & 0xff;
238 		output[j + 2]	= (input[i] >> 40) & 0xff;
239 		output[j + 3]	= (input[i] >> 32) & 0xff;
240 		output[j + 4]	= (input[i] >> 24) & 0xff;
241 		output[j + 5]	= (input[i] >> 16) & 0xff;
242 		output[j + 6]	= (input[i] >>  8) & 0xff;
243 		output[j + 7]	= input[i] & 0xff;
244 	}
245 }
246 
247 /*
248  * Implements the SHA-384, SHA-512 and SHA-512/t hash algos - to select
249  * between them pass the appropriate initial values for 'H'. The output
250  * of this function is truncated to the first 256 bits that fit into 'zcp'.
251  */
252 static void
253 SHA512(uint64_t *H, const void *buf, uint64_t size, zio_cksum_t *zcp)
254 {
255 	uint64_t	c64[2];
256 	uint8_t		pad[256];
257 	unsigned	padsize = size & 127;
258 	unsigned	i, k;
259 
260 	/* process all blocks up to the last one */
261 	for (i = 0; i < size - padsize; i += 128)
262 		SHA512Transform(H, (const uint8_t *)buf + i);
263 
264 	/* process the last block and padding */
265 	for (k = 0; k < padsize; k++)
266 		pad[k] = ((const uint8_t *)buf)[k + i];
267 
268 	if (padsize < 112) {
269 		for (pad[padsize++] = 0x80; padsize < 112; padsize++)
270 			pad[padsize] = 0;
271 	} else {
272 		for (pad[padsize++] = 0x80; padsize < 240; padsize++)
273 			pad[padsize] = 0;
274 	}
275 
276 	c64[0] = 0;
277 	c64[1] = size << 3;
278 	Encode64(pad+padsize, c64, sizeof (c64));
279 	padsize += sizeof (c64);
280 
281 	for (i = 0; i < padsize; i += 128)
282 		SHA512Transform(H, pad + i);
283 
284 	/* truncate the output to the first 256 bits which fit into 'zcp' */
285 	Encode64((uint8_t *)zcp, H, sizeof (uint64_t) * 4);
286 }
287 
288 static void
289 zio_checksum_SHA256(const void *buf, uint64_t size,
290     const void *ctx_template __unused, zio_cksum_t *zcp)
291 {
292 	/* SHA-256 as per FIPS 180-4. */
293 	uint32_t	H[] = {
294 		0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
295 		0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19
296 	};
297 	SHA256(H, buf, size, zcp);
298 }
299 
300 static void
301 zio_checksum_SHA512_native(const void *buf, uint64_t size,
302     const void *ctx_template __unused, zio_cksum_t *zcp)
303 {
304 	/* SHA-512/256 as per FIPS 180-4. */
305 	uint64_t	H[] = {
306 		0x22312194FC2BF72CULL, 0x9F555FA3C84C64C2ULL,
307 		0x2393B86B6F53B151ULL, 0x963877195940EABDULL,
308 		0x96283EE2A88EFFE3ULL, 0xBE5E1E2553863992ULL,
309 		0x2B0199FC2C85B8AAULL, 0x0EB72DDC81C52CA2ULL
310 	};
311 	SHA512(H, buf, size, zcp);
312 }
313 
314 static void
315 zio_checksum_SHA512_byteswap(const void *buf, uint64_t size,
316     const void *ctx_template, zio_cksum_t *zcp)
317 {
318 	zio_cksum_t	tmp;
319 
320 	zio_checksum_SHA512_native(buf, size, ctx_template, &tmp);
321 	zcp->zc_word[0] = BSWAP_64(tmp.zc_word[0]);
322 	zcp->zc_word[1] = BSWAP_64(tmp.zc_word[1]);
323 	zcp->zc_word[2] = BSWAP_64(tmp.zc_word[2]);
324 	zcp->zc_word[3] = BSWAP_64(tmp.zc_word[3]);
325 }
326