1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3 * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
4 *
5 * This is an implementation of the BLAKE2s hash and PRF functions.
6 *
7 * Information: https://blake2.net/
8 *
9 */
10
11 #include <crypto/blake2s.h>
12 #include <linux/bug.h>
13 #include <linux/export.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18
19 static const u8 blake2s_sigma[10][16] = {
20 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 },
21 { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 },
22 { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 },
23 { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 },
24 { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 },
25 { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 },
26 { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 },
27 { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 },
28 { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 },
29 { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 },
30 };
31
blake2s_increment_counter(struct blake2s_ctx * ctx,u32 inc)32 static inline void blake2s_increment_counter(struct blake2s_ctx *ctx, u32 inc)
33 {
34 ctx->t[0] += inc;
35 ctx->t[1] += (ctx->t[0] < inc);
36 }
37
38 static void __maybe_unused
blake2s_compress_generic(struct blake2s_ctx * ctx,const u8 * data,size_t nblocks,u32 inc)39 blake2s_compress_generic(struct blake2s_ctx *ctx,
40 const u8 *data, size_t nblocks, u32 inc)
41 {
42 u32 m[16];
43 u32 v[16];
44 int i;
45
46 WARN_ON(IS_ENABLED(DEBUG) &&
47 (nblocks > 1 && inc != BLAKE2S_BLOCK_SIZE));
48
49 while (nblocks > 0) {
50 blake2s_increment_counter(ctx, inc);
51 memcpy(m, data, BLAKE2S_BLOCK_SIZE);
52 le32_to_cpu_array(m, ARRAY_SIZE(m));
53 memcpy(v, ctx->h, 32);
54 v[ 8] = BLAKE2S_IV0;
55 v[ 9] = BLAKE2S_IV1;
56 v[10] = BLAKE2S_IV2;
57 v[11] = BLAKE2S_IV3;
58 v[12] = BLAKE2S_IV4 ^ ctx->t[0];
59 v[13] = BLAKE2S_IV5 ^ ctx->t[1];
60 v[14] = BLAKE2S_IV6 ^ ctx->f[0];
61 v[15] = BLAKE2S_IV7 ^ ctx->f[1];
62
63 #define G(r, i, a, b, c, d) do { \
64 a += b + m[blake2s_sigma[r][2 * i + 0]]; \
65 d = ror32(d ^ a, 16); \
66 c += d; \
67 b = ror32(b ^ c, 12); \
68 a += b + m[blake2s_sigma[r][2 * i + 1]]; \
69 d = ror32(d ^ a, 8); \
70 c += d; \
71 b = ror32(b ^ c, 7); \
72 } while (0)
73
74 #define ROUND(r) do { \
75 G(r, 0, v[0], v[ 4], v[ 8], v[12]); \
76 G(r, 1, v[1], v[ 5], v[ 9], v[13]); \
77 G(r, 2, v[2], v[ 6], v[10], v[14]); \
78 G(r, 3, v[3], v[ 7], v[11], v[15]); \
79 G(r, 4, v[0], v[ 5], v[10], v[15]); \
80 G(r, 5, v[1], v[ 6], v[11], v[12]); \
81 G(r, 6, v[2], v[ 7], v[ 8], v[13]); \
82 G(r, 7, v[3], v[ 4], v[ 9], v[14]); \
83 } while (0)
84 ROUND(0);
85 ROUND(1);
86 ROUND(2);
87 ROUND(3);
88 ROUND(4);
89 ROUND(5);
90 ROUND(6);
91 ROUND(7);
92 ROUND(8);
93 ROUND(9);
94
95 #undef G
96 #undef ROUND
97
98 for (i = 0; i < 8; ++i)
99 ctx->h[i] ^= v[i] ^ v[i + 8];
100
101 data += BLAKE2S_BLOCK_SIZE;
102 --nblocks;
103 }
104 }
105
106 #ifdef CONFIG_CRYPTO_LIB_BLAKE2S_ARCH
107 #include "blake2s.h" /* $(SRCARCH)/blake2s.h */
108 #else
109 #define blake2s_compress blake2s_compress_generic
110 #endif
111
blake2s_set_lastblock(struct blake2s_ctx * ctx)112 static inline void blake2s_set_lastblock(struct blake2s_ctx *ctx)
113 {
114 ctx->f[0] = -1;
115 }
116
blake2s_update(struct blake2s_ctx * ctx,const u8 * in,size_t inlen)117 void blake2s_update(struct blake2s_ctx *ctx, const u8 *in, size_t inlen)
118 {
119 const size_t fill = BLAKE2S_BLOCK_SIZE - ctx->buflen;
120
121 if (unlikely(!inlen))
122 return;
123 if (inlen > fill) {
124 memcpy(ctx->buf + ctx->buflen, in, fill);
125 blake2s_compress(ctx, ctx->buf, 1, BLAKE2S_BLOCK_SIZE);
126 ctx->buflen = 0;
127 in += fill;
128 inlen -= fill;
129 }
130 if (inlen > BLAKE2S_BLOCK_SIZE) {
131 const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE);
132
133 blake2s_compress(ctx, in, nblocks - 1, BLAKE2S_BLOCK_SIZE);
134 in += BLAKE2S_BLOCK_SIZE * (nblocks - 1);
135 inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1);
136 }
137 memcpy(ctx->buf + ctx->buflen, in, inlen);
138 ctx->buflen += inlen;
139 }
140 EXPORT_SYMBOL(blake2s_update);
141
blake2s_final(struct blake2s_ctx * ctx,u8 * out)142 void blake2s_final(struct blake2s_ctx *ctx, u8 *out)
143 {
144 WARN_ON(IS_ENABLED(DEBUG) && !out);
145 blake2s_set_lastblock(ctx);
146 memset(ctx->buf + ctx->buflen, 0,
147 BLAKE2S_BLOCK_SIZE - ctx->buflen); /* Padding */
148 blake2s_compress(ctx, ctx->buf, 1, ctx->buflen);
149 cpu_to_le32_array(ctx->h, ARRAY_SIZE(ctx->h));
150 memcpy(out, ctx->h, ctx->outlen);
151 memzero_explicit(ctx, sizeof(*ctx));
152 }
153 EXPORT_SYMBOL(blake2s_final);
154
155 #ifdef blake2s_mod_init_arch
blake2s_mod_init(void)156 static int __init blake2s_mod_init(void)
157 {
158 blake2s_mod_init_arch();
159 return 0;
160 }
161 subsys_initcall(blake2s_mod_init);
162 #endif
163
164 MODULE_DESCRIPTION("BLAKE2s hash function");
165 MODULE_AUTHOR("Jason A. Donenfeld <Jason@zx2c4.com>");
166