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4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
22 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
26 #include <sys/zfs_context.h>
28 #include <sys/zio_checksum.h>
31 * SHA-256 checksum, as specified in FIPS 180-3, available at:
32 * http://csrc.nist.gov/publications/PubsFIPS.html
34 * This is a very compact implementation of SHA-256.
35 * It is designed to be simple and portable, not to be fast.
39 * The literal definitions of Ch() and Maj() according to FIPS 180-3 are:
41 * Ch(x, y, z) (x & y) ^ (~x & z)
42 * Maj(x, y, z) (x & y) ^ (x & z) ^ (y & z)
44 * We use equivalent logical reductions here that require one less op.
46 #define Ch(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
47 #define Maj(x, y, z) (((x) & (y)) ^ ((z) & ((x) ^ (y))))
48 #define Rot32(x, s) (((x) >> s) | ((x) << (32 - s)))
49 #define SIGMA0(x) (Rot32(x, 2) ^ Rot32(x, 13) ^ Rot32(x, 22))
50 #define SIGMA1(x) (Rot32(x, 6) ^ Rot32(x, 11) ^ Rot32(x, 25))
51 #define sigma0(x) (Rot32(x, 7) ^ Rot32(x, 18) ^ ((x) >> 3))
52 #define sigma1(x) (Rot32(x, 17) ^ Rot32(x, 19) ^ ((x) >> 10))
54 static const uint32_t SHA256_K
[64] = {
55 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
56 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
57 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
58 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
59 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
60 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
61 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
62 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
63 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
64 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
65 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
66 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
67 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
68 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
69 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
70 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
74 SHA256Transform(uint32_t *H
, const uint8_t *cp
)
76 uint32_t a
, b
, c
, d
, e
, f
, g
, h
, t
, T1
, T2
, W
[64];
78 for (t
= 0; t
< 16; t
++, cp
+= 4)
79 W
[t
] = (cp
[0] << 24) | (cp
[1] << 16) | (cp
[2] << 8) | cp
[3];
81 for (t
= 16; t
< 64; t
++)
82 W
[t
] = sigma1(W
[t
- 2]) + W
[t
- 7] +
83 sigma0(W
[t
- 15]) + W
[t
- 16];
85 a
= H
[0]; b
= H
[1]; c
= H
[2]; d
= H
[3];
86 e
= H
[4]; f
= H
[5]; g
= H
[6]; h
= H
[7];
88 for (t
= 0; t
< 64; t
++) {
89 T1
= h
+ SIGMA1(e
) + Ch(e
, f
, g
) + SHA256_K
[t
] + W
[t
];
90 T2
= SIGMA0(a
) + Maj(a
, b
, c
);
91 h
= g
; g
= f
; f
= e
; e
= d
+ T1
;
92 d
= c
; c
= b
; b
= a
; a
= T1
+ T2
;
95 H
[0] += a
; H
[1] += b
; H
[2] += c
; H
[3] += d
;
96 H
[4] += e
; H
[5] += f
; H
[6] += g
; H
[7] += h
;
100 zio_checksum_SHA256(const void *buf
, uint64_t size
, zio_cksum_t
*zcp
)
102 uint32_t H
[8] = { 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
103 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 };
107 for (i
= 0; i
< (size
& ~63ULL); i
+= 64)
108 SHA256Transform(H
, (uint8_t *)buf
+ i
);
110 for (padsize
= 0; i
< size
; i
++)
111 pad
[padsize
++] = *((uint8_t *)buf
+ i
);
113 for (pad
[padsize
++] = 0x80; (padsize
& 63) != 56; padsize
++)
116 for (i
= 56; i
>= 0; i
-= 8)
117 pad
[padsize
++] = (size
<< 3) >> i
;
119 for (i
= 0; i
< padsize
; i
+= 64)
120 SHA256Transform(H
, pad
+ i
);
122 ZIO_SET_CHECKSUM(zcp
,
123 (uint64_t)H
[0] << 32 | H
[1],
124 (uint64_t)H
[2] << 32 | H
[3],
125 (uint64_t)H
[4] << 32 | H
[5],
126 (uint64_t)H
[6] << 32 | H
[7]);