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 #include "blake2s.h" 11 #include <linux/kernel.h> 12 13 static inline u32 ror32(u32 v, int n) 14 { 15 return (v >> n) | (v << (32 - n)); 16 } 17 18 static inline void le32_to_cpu_array(u32 a[], size_t n) 19 { 20 for (size_t i = 0; i < n; i++) 21 a[i] = le32_to_cpu((__force __le32)a[i]); 22 } 23 24 static inline void cpu_to_le32_array(u32 a[], size_t n) 25 { 26 for (size_t i = 0; i < n; i++) 27 a[i] = (__force u32)cpu_to_le32(a[i]); 28 } 29 30 static const u8 blake2s_sigma[10][16] = { 31 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, 32 { 14, 10, 4, 8, 9, 15, 13, 6, 1, 12, 0, 2, 11, 7, 5, 3 }, 33 { 11, 8, 12, 0, 5, 2, 15, 13, 10, 14, 3, 6, 7, 1, 9, 4 }, 34 { 7, 9, 3, 1, 13, 12, 11, 14, 2, 6, 5, 10, 4, 0, 15, 8 }, 35 { 9, 0, 5, 7, 2, 4, 10, 15, 14, 1, 11, 12, 6, 8, 3, 13 }, 36 { 2, 12, 6, 10, 0, 11, 8, 3, 4, 13, 7, 5, 15, 14, 1, 9 }, 37 { 12, 5, 1, 15, 14, 13, 4, 10, 0, 7, 6, 3, 9, 2, 8, 11 }, 38 { 13, 11, 7, 14, 12, 1, 3, 9, 5, 0, 15, 4, 8, 6, 2, 10 }, 39 { 6, 15, 14, 9, 11, 3, 0, 8, 12, 2, 13, 7, 1, 4, 10, 5 }, 40 { 10, 2, 8, 4, 7, 6, 1, 5, 15, 11, 9, 14, 3, 12, 13, 0 }, 41 }; 42 43 static inline void blake2s_increment_counter(struct blake2s_ctx *ctx, u32 inc) 44 { 45 ctx->t[0] += inc; 46 ctx->t[1] += (ctx->t[0] < inc); 47 } 48 49 static void blake2s_compress(struct blake2s_ctx *ctx, 50 const u8 *data, size_t nblocks, u32 inc) 51 { 52 u32 m[16]; 53 u32 v[16]; 54 int i; 55 56 while (nblocks > 0) { 57 blake2s_increment_counter(ctx, inc); 58 memcpy(m, data, BLAKE2S_BLOCK_SIZE); 59 le32_to_cpu_array(m, ARRAY_SIZE(m)); 60 memcpy(v, ctx->h, 32); 61 v[ 8] = BLAKE2S_IV0; 62 v[ 9] = BLAKE2S_IV1; 63 v[10] = BLAKE2S_IV2; 64 v[11] = BLAKE2S_IV3; 65 v[12] = BLAKE2S_IV4 ^ ctx->t[0]; 66 v[13] = BLAKE2S_IV5 ^ ctx->t[1]; 67 v[14] = BLAKE2S_IV6 ^ ctx->f[0]; 68 v[15] = BLAKE2S_IV7 ^ ctx->f[1]; 69 70 #define G(r, i, a, b, c, d) do { \ 71 a += b + m[blake2s_sigma[r][2 * i + 0]]; \ 72 d = ror32(d ^ a, 16); \ 73 c += d; \ 74 b = ror32(b ^ c, 12); \ 75 a += b + m[blake2s_sigma[r][2 * i + 1]]; \ 76 d = ror32(d ^ a, 8); \ 77 c += d; \ 78 b = ror32(b ^ c, 7); \ 79 } while (0) 80 81 #define ROUND(r) do { \ 82 G(r, 0, v[0], v[ 4], v[ 8], v[12]); \ 83 G(r, 1, v[1], v[ 5], v[ 9], v[13]); \ 84 G(r, 2, v[2], v[ 6], v[10], v[14]); \ 85 G(r, 3, v[3], v[ 7], v[11], v[15]); \ 86 G(r, 4, v[0], v[ 5], v[10], v[15]); \ 87 G(r, 5, v[1], v[ 6], v[11], v[12]); \ 88 G(r, 6, v[2], v[ 7], v[ 8], v[13]); \ 89 G(r, 7, v[3], v[ 4], v[ 9], v[14]); \ 90 } while (0) 91 ROUND(0); 92 ROUND(1); 93 ROUND(2); 94 ROUND(3); 95 ROUND(4); 96 ROUND(5); 97 ROUND(6); 98 ROUND(7); 99 ROUND(8); 100 ROUND(9); 101 102 #undef G 103 #undef ROUND 104 105 for (i = 0; i < 8; ++i) 106 ctx->h[i] ^= v[i] ^ v[i + 8]; 107 108 data += BLAKE2S_BLOCK_SIZE; 109 --nblocks; 110 } 111 } 112 113 static inline void blake2s_set_lastblock(struct blake2s_ctx *ctx) 114 { 115 ctx->f[0] = -1; 116 } 117 118 void blake2s_update(struct blake2s_ctx *ctx, const u8 *in, size_t inlen) 119 { 120 const size_t fill = BLAKE2S_BLOCK_SIZE - ctx->buflen; 121 122 if (unlikely(!inlen)) 123 return; 124 if (inlen > fill) { 125 memcpy(ctx->buf + ctx->buflen, in, fill); 126 blake2s_compress(ctx, ctx->buf, 1, BLAKE2S_BLOCK_SIZE); 127 ctx->buflen = 0; 128 in += fill; 129 inlen -= fill; 130 } 131 if (inlen > BLAKE2S_BLOCK_SIZE) { 132 const size_t nblocks = DIV_ROUND_UP(inlen, BLAKE2S_BLOCK_SIZE); 133 134 blake2s_compress(ctx, in, nblocks - 1, BLAKE2S_BLOCK_SIZE); 135 in += BLAKE2S_BLOCK_SIZE * (nblocks - 1); 136 inlen -= BLAKE2S_BLOCK_SIZE * (nblocks - 1); 137 } 138 memcpy(ctx->buf + ctx->buflen, in, inlen); 139 ctx->buflen += inlen; 140 } 141 142 void blake2s_final(struct blake2s_ctx *ctx, u8 *out) 143 { 144 blake2s_set_lastblock(ctx); 145 memset(ctx->buf + ctx->buflen, 0, 146 BLAKE2S_BLOCK_SIZE - ctx->buflen); /* Padding */ 147 blake2s_compress(ctx, ctx->buf, 1, ctx->buflen); 148 cpu_to_le32_array(ctx->h, ARRAY_SIZE(ctx->h)); 149 memcpy(out, ctx->h, ctx->outlen); 150 memset(ctx, 0, sizeof(*ctx)); 151 } 152