1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * GRUB -- GRand Unified Bootloader
4 * Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
5 */
6 /*
7 * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
8 * Use is subject to license terms.
9 */
10
11 #include <common.h>
12 #include <malloc.h>
13 #include <linux/stat.h>
14 #include <linux/time.h>
15 #include <linux/ctype.h>
16 #include <asm/byteorder.h>
17 #include "zfs_common.h"
18
19 #include <zfs/zfs.h>
20 #include <zfs/zio.h>
21 #include <zfs/dnode.h>
22 #include <zfs/uberblock_impl.h>
23 #include <zfs/vdev_impl.h>
24 #include <zfs/zio_checksum.h>
25 #include <zfs/zap_impl.h>
26 #include <zfs/zap_leaf.h>
27 #include <zfs/zfs_znode.h>
28 #include <zfs/dmu.h>
29 #include <zfs/dmu_objset.h>
30 #include <zfs/dsl_dir.h>
31 #include <zfs/dsl_dataset.h>
32
33 /*
34 * SHA-256 checksum, as specified in FIPS 180-2, available at:
35 * http://csrc.nist.gov/cryptval
36 *
37 * This is a very compact implementation of SHA-256.
38 * It is designed to be simple and portable, not to be fast.
39 */
40
41 /*
42 * The literal definitions according to FIPS180-2 would be:
43 *
44 * Ch(x, y, z) (((x) & (y)) ^ ((~(x)) & (z)))
45 * Maj(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
46 *
47 * We use logical equivalents which require one less op.
48 */
49 #define Ch(x, y, z) ((z) ^ ((x) & ((y) ^ (z))))
50 #define Maj(x, y, z) (((x) & (y)) ^ ((z) & ((x) ^ (y))))
51 #define Rot32(x, s) (((x) >> s) | ((x) << (32 - s)))
52 #define SIGMA0(x) (Rot32(x, 2) ^ Rot32(x, 13) ^ Rot32(x, 22))
53 #define SIGMA1(x) (Rot32(x, 6) ^ Rot32(x, 11) ^ Rot32(x, 25))
54 #define sigma0(x) (Rot32(x, 7) ^ Rot32(x, 18) ^ ((x) >> 3))
55 #define sigma1(x) (Rot32(x, 17) ^ Rot32(x, 19) ^ ((x) >> 10))
56
57 static const uint32_t SHA256_K[64] = {
58 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
59 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5,
60 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3,
61 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174,
62 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc,
63 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da,
64 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7,
65 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967,
66 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13,
67 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85,
68 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3,
69 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070,
70 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5,
71 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3,
72 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208,
73 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2
74 };
75
76 static void
SHA256Transform(uint32_t * H,const uint8_t * cp)77 SHA256Transform(uint32_t *H, const uint8_t *cp)
78 {
79 uint32_t a, b, c, d, e, f, g, h, t, T1, T2, W[64];
80
81 for (t = 0; t < 16; t++, cp += 4)
82 W[t] = (cp[0] << 24) | (cp[1] << 16) | (cp[2] << 8) | cp[3];
83
84 for (t = 16; t < 64; t++)
85 W[t] = sigma1(W[t - 2]) + W[t - 7] +
86 sigma0(W[t - 15]) + W[t - 16];
87
88 a = H[0]; b = H[1]; c = H[2]; d = H[3];
89 e = H[4]; f = H[5]; g = H[6]; h = H[7];
90
91 for (t = 0; t < 64; t++) {
92 T1 = h + SIGMA1(e) + Ch(e, f, g) + SHA256_K[t] + W[t];
93 T2 = SIGMA0(a) + Maj(a, b, c);
94 h = g; g = f; f = e; e = d + T1;
95 d = c; c = b; b = a; a = T1 + T2;
96 }
97
98 H[0] += a; H[1] += b; H[2] += c; H[3] += d;
99 H[4] += e; H[5] += f; H[6] += g; H[7] += h;
100 }
101
102 void
zio_checksum_SHA256(const void * buf,uint64_t size,zfs_endian_t endian,zio_cksum_t * zcp)103 zio_checksum_SHA256(const void *buf, uint64_t size,
104 zfs_endian_t endian, zio_cksum_t *zcp)
105 {
106 uint32_t H[8] = { 0x6a09e667, 0xbb67ae85, 0x3c6ef372, 0xa54ff53a,
107 0x510e527f, 0x9b05688c, 0x1f83d9ab, 0x5be0cd19 };
108 uint8_t pad[128];
109 unsigned padsize = size & 63;
110 unsigned i;
111
112 for (i = 0; i < size - padsize; i += 64)
113 SHA256Transform(H, (uint8_t *)buf + i);
114
115 for (i = 0; i < padsize; i++)
116 pad[i] = ((uint8_t *)buf)[i];
117
118 for (pad[padsize++] = 0x80; (padsize & 63) != 56; padsize++)
119 pad[padsize] = 0;
120
121 for (i = 0; i < 8; i++)
122 pad[padsize++] = (size << 3) >> (56 - 8 * i);
123
124 for (i = 0; i < padsize; i += 64)
125 SHA256Transform(H, pad + i);
126
127 zcp->zc_word[0] = cpu_to_zfs64((uint64_t)H[0] << 32 | H[1],
128 endian);
129 zcp->zc_word[1] = cpu_to_zfs64((uint64_t)H[2] << 32 | H[3],
130 endian);
131 zcp->zc_word[2] = cpu_to_zfs64((uint64_t)H[4] << 32 | H[5],
132 endian);
133 zcp->zc_word[3] = cpu_to_zfs64((uint64_t)H[6] << 32 | H[7],
134 endian);
135 }
136