1 /* 2 * Cryptographic API. 3 * 4 * SHA-256, as specified in 5 * http://csrc.nist.gov/cryptval/shs/sha256-384-512.pdf 6 * 7 * SHA-256 code by Jean-Luc Cooke <jlcooke@certainkey.com>. 8 * 9 * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com> 10 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk> 11 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> 12 * 13 * This program is free software; you can redistribute it and/or modify it 14 * under the terms of the GNU General Public License as published by the Free 15 * Software Foundation; either version 2 of the License, or (at your option) 16 * any later version. 17 * 18 */ 19 #include <linux/init.h> 20 #include <linux/module.h> 21 #include <linux/mm.h> 22 #include <linux/crypto.h> 23 #include <linux/types.h> 24 #include <crypto/sha.h> 25 #include <asm/byteorder.h> 26 27 struct sha256_ctx { 28 u32 count[2]; 29 u32 state[8]; 30 u8 buf[128]; 31 }; 32 33 static inline u32 Ch(u32 x, u32 y, u32 z) 34 { 35 return z ^ (x & (y ^ z)); 36 } 37 38 static inline u32 Maj(u32 x, u32 y, u32 z) 39 { 40 return (x & y) | (z & (x | y)); 41 } 42 43 #define e0(x) (ror32(x, 2) ^ ror32(x,13) ^ ror32(x,22)) 44 #define e1(x) (ror32(x, 6) ^ ror32(x,11) ^ ror32(x,25)) 45 #define s0(x) (ror32(x, 7) ^ ror32(x,18) ^ (x >> 3)) 46 #define s1(x) (ror32(x,17) ^ ror32(x,19) ^ (x >> 10)) 47 48 static inline void LOAD_OP(int I, u32 *W, const u8 *input) 49 { 50 W[I] = __be32_to_cpu( ((__be32*)(input))[I] ); 51 } 52 53 static inline void BLEND_OP(int I, u32 *W) 54 { 55 W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16]; 56 } 57 58 static void sha256_transform(u32 *state, const u8 *input) 59 { 60 u32 a, b, c, d, e, f, g, h, t1, t2; 61 u32 W[64]; 62 int i; 63 64 /* load the input */ 65 for (i = 0; i < 16; i++) 66 LOAD_OP(i, W, input); 67 68 /* now blend */ 69 for (i = 16; i < 64; i++) 70 BLEND_OP(i, W); 71 72 /* load the state into our registers */ 73 a=state[0]; b=state[1]; c=state[2]; d=state[3]; 74 e=state[4]; f=state[5]; g=state[6]; h=state[7]; 75 76 /* now iterate */ 77 t1 = h + e1(e) + Ch(e,f,g) + 0x428a2f98 + W[ 0]; 78 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 79 t1 = g + e1(d) + Ch(d,e,f) + 0x71374491 + W[ 1]; 80 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 81 t1 = f + e1(c) + Ch(c,d,e) + 0xb5c0fbcf + W[ 2]; 82 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 83 t1 = e + e1(b) + Ch(b,c,d) + 0xe9b5dba5 + W[ 3]; 84 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 85 t1 = d + e1(a) + Ch(a,b,c) + 0x3956c25b + W[ 4]; 86 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 87 t1 = c + e1(h) + Ch(h,a,b) + 0x59f111f1 + W[ 5]; 88 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 89 t1 = b + e1(g) + Ch(g,h,a) + 0x923f82a4 + W[ 6]; 90 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 91 t1 = a + e1(f) + Ch(f,g,h) + 0xab1c5ed5 + W[ 7]; 92 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 93 94 t1 = h + e1(e) + Ch(e,f,g) + 0xd807aa98 + W[ 8]; 95 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 96 t1 = g + e1(d) + Ch(d,e,f) + 0x12835b01 + W[ 9]; 97 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 98 t1 = f + e1(c) + Ch(c,d,e) + 0x243185be + W[10]; 99 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 100 t1 = e + e1(b) + Ch(b,c,d) + 0x550c7dc3 + W[11]; 101 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 102 t1 = d + e1(a) + Ch(a,b,c) + 0x72be5d74 + W[12]; 103 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 104 t1 = c + e1(h) + Ch(h,a,b) + 0x80deb1fe + W[13]; 105 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 106 t1 = b + e1(g) + Ch(g,h,a) + 0x9bdc06a7 + W[14]; 107 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 108 t1 = a + e1(f) + Ch(f,g,h) + 0xc19bf174 + W[15]; 109 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 110 111 t1 = h + e1(e) + Ch(e,f,g) + 0xe49b69c1 + W[16]; 112 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 113 t1 = g + e1(d) + Ch(d,e,f) + 0xefbe4786 + W[17]; 114 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 115 t1 = f + e1(c) + Ch(c,d,e) + 0x0fc19dc6 + W[18]; 116 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 117 t1 = e + e1(b) + Ch(b,c,d) + 0x240ca1cc + W[19]; 118 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 119 t1 = d + e1(a) + Ch(a,b,c) + 0x2de92c6f + W[20]; 120 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 121 t1 = c + e1(h) + Ch(h,a,b) + 0x4a7484aa + W[21]; 122 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 123 t1 = b + e1(g) + Ch(g,h,a) + 0x5cb0a9dc + W[22]; 124 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 125 t1 = a + e1(f) + Ch(f,g,h) + 0x76f988da + W[23]; 126 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 127 128 t1 = h + e1(e) + Ch(e,f,g) + 0x983e5152 + W[24]; 129 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 130 t1 = g + e1(d) + Ch(d,e,f) + 0xa831c66d + W[25]; 131 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 132 t1 = f + e1(c) + Ch(c,d,e) + 0xb00327c8 + W[26]; 133 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 134 t1 = e + e1(b) + Ch(b,c,d) + 0xbf597fc7 + W[27]; 135 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 136 t1 = d + e1(a) + Ch(a,b,c) + 0xc6e00bf3 + W[28]; 137 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 138 t1 = c + e1(h) + Ch(h,a,b) + 0xd5a79147 + W[29]; 139 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 140 t1 = b + e1(g) + Ch(g,h,a) + 0x06ca6351 + W[30]; 141 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 142 t1 = a + e1(f) + Ch(f,g,h) + 0x14292967 + W[31]; 143 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 144 145 t1 = h + e1(e) + Ch(e,f,g) + 0x27b70a85 + W[32]; 146 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 147 t1 = g + e1(d) + Ch(d,e,f) + 0x2e1b2138 + W[33]; 148 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 149 t1 = f + e1(c) + Ch(c,d,e) + 0x4d2c6dfc + W[34]; 150 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 151 t1 = e + e1(b) + Ch(b,c,d) + 0x53380d13 + W[35]; 152 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 153 t1 = d + e1(a) + Ch(a,b,c) + 0x650a7354 + W[36]; 154 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 155 t1 = c + e1(h) + Ch(h,a,b) + 0x766a0abb + W[37]; 156 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 157 t1 = b + e1(g) + Ch(g,h,a) + 0x81c2c92e + W[38]; 158 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 159 t1 = a + e1(f) + Ch(f,g,h) + 0x92722c85 + W[39]; 160 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 161 162 t1 = h + e1(e) + Ch(e,f,g) + 0xa2bfe8a1 + W[40]; 163 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 164 t1 = g + e1(d) + Ch(d,e,f) + 0xa81a664b + W[41]; 165 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 166 t1 = f + e1(c) + Ch(c,d,e) + 0xc24b8b70 + W[42]; 167 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 168 t1 = e + e1(b) + Ch(b,c,d) + 0xc76c51a3 + W[43]; 169 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 170 t1 = d + e1(a) + Ch(a,b,c) + 0xd192e819 + W[44]; 171 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 172 t1 = c + e1(h) + Ch(h,a,b) + 0xd6990624 + W[45]; 173 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 174 t1 = b + e1(g) + Ch(g,h,a) + 0xf40e3585 + W[46]; 175 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 176 t1 = a + e1(f) + Ch(f,g,h) + 0x106aa070 + W[47]; 177 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 178 179 t1 = h + e1(e) + Ch(e,f,g) + 0x19a4c116 + W[48]; 180 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 181 t1 = g + e1(d) + Ch(d,e,f) + 0x1e376c08 + W[49]; 182 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 183 t1 = f + e1(c) + Ch(c,d,e) + 0x2748774c + W[50]; 184 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 185 t1 = e + e1(b) + Ch(b,c,d) + 0x34b0bcb5 + W[51]; 186 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 187 t1 = d + e1(a) + Ch(a,b,c) + 0x391c0cb3 + W[52]; 188 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 189 t1 = c + e1(h) + Ch(h,a,b) + 0x4ed8aa4a + W[53]; 190 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 191 t1 = b + e1(g) + Ch(g,h,a) + 0x5b9cca4f + W[54]; 192 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 193 t1 = a + e1(f) + Ch(f,g,h) + 0x682e6ff3 + W[55]; 194 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 195 196 t1 = h + e1(e) + Ch(e,f,g) + 0x748f82ee + W[56]; 197 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 198 t1 = g + e1(d) + Ch(d,e,f) + 0x78a5636f + W[57]; 199 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 200 t1 = f + e1(c) + Ch(c,d,e) + 0x84c87814 + W[58]; 201 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 202 t1 = e + e1(b) + Ch(b,c,d) + 0x8cc70208 + W[59]; 203 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 204 t1 = d + e1(a) + Ch(a,b,c) + 0x90befffa + W[60]; 205 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 206 t1 = c + e1(h) + Ch(h,a,b) + 0xa4506ceb + W[61]; 207 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 208 t1 = b + e1(g) + Ch(g,h,a) + 0xbef9a3f7 + W[62]; 209 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 210 t1 = a + e1(f) + Ch(f,g,h) + 0xc67178f2 + W[63]; 211 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 212 213 state[0] += a; state[1] += b; state[2] += c; state[3] += d; 214 state[4] += e; state[5] += f; state[6] += g; state[7] += h; 215 216 /* clear any sensitive info... */ 217 a = b = c = d = e = f = g = h = t1 = t2 = 0; 218 memset(W, 0, 64 * sizeof(u32)); 219 } 220 221 static void sha256_init(struct crypto_tfm *tfm) 222 { 223 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 224 sctx->state[0] = SHA256_H0; 225 sctx->state[1] = SHA256_H1; 226 sctx->state[2] = SHA256_H2; 227 sctx->state[3] = SHA256_H3; 228 sctx->state[4] = SHA256_H4; 229 sctx->state[5] = SHA256_H5; 230 sctx->state[6] = SHA256_H6; 231 sctx->state[7] = SHA256_H7; 232 sctx->count[0] = sctx->count[1] = 0; 233 } 234 235 static void sha256_update(struct crypto_tfm *tfm, const u8 *data, 236 unsigned int len) 237 { 238 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 239 unsigned int i, index, part_len; 240 241 /* Compute number of bytes mod 128 */ 242 index = (unsigned int)((sctx->count[0] >> 3) & 0x3f); 243 244 /* Update number of bits */ 245 if ((sctx->count[0] += (len << 3)) < (len << 3)) { 246 sctx->count[1]++; 247 sctx->count[1] += (len >> 29); 248 } 249 250 part_len = 64 - index; 251 252 /* Transform as many times as possible. */ 253 if (len >= part_len) { 254 memcpy(&sctx->buf[index], data, part_len); 255 sha256_transform(sctx->state, sctx->buf); 256 257 for (i = part_len; i + 63 < len; i += 64) 258 sha256_transform(sctx->state, &data[i]); 259 index = 0; 260 } else { 261 i = 0; 262 } 263 264 /* Buffer remaining input */ 265 memcpy(&sctx->buf[index], &data[i], len-i); 266 } 267 268 static void sha256_final(struct crypto_tfm *tfm, u8 *out) 269 { 270 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 271 __be32 *dst = (__be32 *)out; 272 __be32 bits[2]; 273 unsigned int index, pad_len; 274 int i; 275 static const u8 padding[64] = { 0x80, }; 276 277 /* Save number of bits */ 278 bits[1] = cpu_to_be32(sctx->count[0]); 279 bits[0] = cpu_to_be32(sctx->count[1]); 280 281 /* Pad out to 56 mod 64. */ 282 index = (sctx->count[0] >> 3) & 0x3f; 283 pad_len = (index < 56) ? (56 - index) : ((64+56) - index); 284 sha256_update(tfm, padding, pad_len); 285 286 /* Append length (before padding) */ 287 sha256_update(tfm, (const u8 *)bits, sizeof(bits)); 288 289 /* Store state in digest */ 290 for (i = 0; i < 8; i++) 291 dst[i] = cpu_to_be32(sctx->state[i]); 292 293 /* Zeroize sensitive information. */ 294 memset(sctx, 0, sizeof(*sctx)); 295 } 296 297 298 static struct crypto_alg alg = { 299 .cra_name = "sha256", 300 .cra_driver_name= "sha256-generic", 301 .cra_flags = CRYPTO_ALG_TYPE_DIGEST, 302 .cra_blocksize = SHA256_BLOCK_SIZE, 303 .cra_ctxsize = sizeof(struct sha256_ctx), 304 .cra_module = THIS_MODULE, 305 .cra_alignmask = 3, 306 .cra_list = LIST_HEAD_INIT(alg.cra_list), 307 .cra_u = { .digest = { 308 .dia_digestsize = SHA256_DIGEST_SIZE, 309 .dia_init = sha256_init, 310 .dia_update = sha256_update, 311 .dia_final = sha256_final } } 312 }; 313 314 static int __init init(void) 315 { 316 return crypto_register_alg(&alg); 317 } 318 319 static void __exit fini(void) 320 { 321 crypto_unregister_alg(&alg); 322 } 323 324 module_init(init); 325 module_exit(fini); 326 327 MODULE_LICENSE("GPL"); 328 MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm"); 329 330 MODULE_ALIAS("sha256"); 331