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 <asm/scatterlist.h> 25 #include <asm/byteorder.h> 26 27 #define SHA256_DIGEST_SIZE 32 28 #define SHA256_HMAC_BLOCK_SIZE 64 29 30 struct sha256_ctx { 31 u32 count[2]; 32 u32 state[8]; 33 u8 buf[128]; 34 }; 35 36 static inline u32 Ch(u32 x, u32 y, u32 z) 37 { 38 return z ^ (x & (y ^ z)); 39 } 40 41 static inline u32 Maj(u32 x, u32 y, u32 z) 42 { 43 return (x & y) | (z & (x | y)); 44 } 45 46 #define e0(x) (ror32(x, 2) ^ ror32(x,13) ^ ror32(x,22)) 47 #define e1(x) (ror32(x, 6) ^ ror32(x,11) ^ ror32(x,25)) 48 #define s0(x) (ror32(x, 7) ^ ror32(x,18) ^ (x >> 3)) 49 #define s1(x) (ror32(x,17) ^ ror32(x,19) ^ (x >> 10)) 50 51 #define H0 0x6a09e667 52 #define H1 0xbb67ae85 53 #define H2 0x3c6ef372 54 #define H3 0xa54ff53a 55 #define H4 0x510e527f 56 #define H5 0x9b05688c 57 #define H6 0x1f83d9ab 58 #define H7 0x5be0cd19 59 60 static inline void LOAD_OP(int I, u32 *W, const u8 *input) 61 { 62 W[I] = __be32_to_cpu( ((__be32*)(input))[I] ); 63 } 64 65 static inline void BLEND_OP(int I, u32 *W) 66 { 67 W[I] = s1(W[I-2]) + W[I-7] + s0(W[I-15]) + W[I-16]; 68 } 69 70 static void sha256_transform(u32 *state, const u8 *input) 71 { 72 u32 a, b, c, d, e, f, g, h, t1, t2; 73 u32 W[64]; 74 int i; 75 76 /* load the input */ 77 for (i = 0; i < 16; i++) 78 LOAD_OP(i, W, input); 79 80 /* now blend */ 81 for (i = 16; i < 64; i++) 82 BLEND_OP(i, W); 83 84 /* load the state into our registers */ 85 a=state[0]; b=state[1]; c=state[2]; d=state[3]; 86 e=state[4]; f=state[5]; g=state[6]; h=state[7]; 87 88 /* now iterate */ 89 t1 = h + e1(e) + Ch(e,f,g) + 0x428a2f98 + W[ 0]; 90 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 91 t1 = g + e1(d) + Ch(d,e,f) + 0x71374491 + W[ 1]; 92 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 93 t1 = f + e1(c) + Ch(c,d,e) + 0xb5c0fbcf + W[ 2]; 94 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 95 t1 = e + e1(b) + Ch(b,c,d) + 0xe9b5dba5 + W[ 3]; 96 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 97 t1 = d + e1(a) + Ch(a,b,c) + 0x3956c25b + W[ 4]; 98 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 99 t1 = c + e1(h) + Ch(h,a,b) + 0x59f111f1 + W[ 5]; 100 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 101 t1 = b + e1(g) + Ch(g,h,a) + 0x923f82a4 + W[ 6]; 102 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 103 t1 = a + e1(f) + Ch(f,g,h) + 0xab1c5ed5 + W[ 7]; 104 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 105 106 t1 = h + e1(e) + Ch(e,f,g) + 0xd807aa98 + W[ 8]; 107 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 108 t1 = g + e1(d) + Ch(d,e,f) + 0x12835b01 + W[ 9]; 109 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 110 t1 = f + e1(c) + Ch(c,d,e) + 0x243185be + W[10]; 111 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 112 t1 = e + e1(b) + Ch(b,c,d) + 0x550c7dc3 + W[11]; 113 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 114 t1 = d + e1(a) + Ch(a,b,c) + 0x72be5d74 + W[12]; 115 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 116 t1 = c + e1(h) + Ch(h,a,b) + 0x80deb1fe + W[13]; 117 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 118 t1 = b + e1(g) + Ch(g,h,a) + 0x9bdc06a7 + W[14]; 119 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 120 t1 = a + e1(f) + Ch(f,g,h) + 0xc19bf174 + W[15]; 121 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 122 123 t1 = h + e1(e) + Ch(e,f,g) + 0xe49b69c1 + W[16]; 124 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 125 t1 = g + e1(d) + Ch(d,e,f) + 0xefbe4786 + W[17]; 126 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 127 t1 = f + e1(c) + Ch(c,d,e) + 0x0fc19dc6 + W[18]; 128 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 129 t1 = e + e1(b) + Ch(b,c,d) + 0x240ca1cc + W[19]; 130 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 131 t1 = d + e1(a) + Ch(a,b,c) + 0x2de92c6f + W[20]; 132 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 133 t1 = c + e1(h) + Ch(h,a,b) + 0x4a7484aa + W[21]; 134 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 135 t1 = b + e1(g) + Ch(g,h,a) + 0x5cb0a9dc + W[22]; 136 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 137 t1 = a + e1(f) + Ch(f,g,h) + 0x76f988da + W[23]; 138 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 139 140 t1 = h + e1(e) + Ch(e,f,g) + 0x983e5152 + W[24]; 141 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 142 t1 = g + e1(d) + Ch(d,e,f) + 0xa831c66d + W[25]; 143 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 144 t1 = f + e1(c) + Ch(c,d,e) + 0xb00327c8 + W[26]; 145 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 146 t1 = e + e1(b) + Ch(b,c,d) + 0xbf597fc7 + W[27]; 147 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 148 t1 = d + e1(a) + Ch(a,b,c) + 0xc6e00bf3 + W[28]; 149 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 150 t1 = c + e1(h) + Ch(h,a,b) + 0xd5a79147 + W[29]; 151 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 152 t1 = b + e1(g) + Ch(g,h,a) + 0x06ca6351 + W[30]; 153 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 154 t1 = a + e1(f) + Ch(f,g,h) + 0x14292967 + W[31]; 155 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 156 157 t1 = h + e1(e) + Ch(e,f,g) + 0x27b70a85 + W[32]; 158 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 159 t1 = g + e1(d) + Ch(d,e,f) + 0x2e1b2138 + W[33]; 160 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 161 t1 = f + e1(c) + Ch(c,d,e) + 0x4d2c6dfc + W[34]; 162 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 163 t1 = e + e1(b) + Ch(b,c,d) + 0x53380d13 + W[35]; 164 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 165 t1 = d + e1(a) + Ch(a,b,c) + 0x650a7354 + W[36]; 166 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 167 t1 = c + e1(h) + Ch(h,a,b) + 0x766a0abb + W[37]; 168 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 169 t1 = b + e1(g) + Ch(g,h,a) + 0x81c2c92e + W[38]; 170 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 171 t1 = a + e1(f) + Ch(f,g,h) + 0x92722c85 + W[39]; 172 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 173 174 t1 = h + e1(e) + Ch(e,f,g) + 0xa2bfe8a1 + W[40]; 175 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 176 t1 = g + e1(d) + Ch(d,e,f) + 0xa81a664b + W[41]; 177 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 178 t1 = f + e1(c) + Ch(c,d,e) + 0xc24b8b70 + W[42]; 179 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 180 t1 = e + e1(b) + Ch(b,c,d) + 0xc76c51a3 + W[43]; 181 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 182 t1 = d + e1(a) + Ch(a,b,c) + 0xd192e819 + W[44]; 183 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 184 t1 = c + e1(h) + Ch(h,a,b) + 0xd6990624 + W[45]; 185 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 186 t1 = b + e1(g) + Ch(g,h,a) + 0xf40e3585 + W[46]; 187 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 188 t1 = a + e1(f) + Ch(f,g,h) + 0x106aa070 + W[47]; 189 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 190 191 t1 = h + e1(e) + Ch(e,f,g) + 0x19a4c116 + W[48]; 192 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 193 t1 = g + e1(d) + Ch(d,e,f) + 0x1e376c08 + W[49]; 194 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 195 t1 = f + e1(c) + Ch(c,d,e) + 0x2748774c + W[50]; 196 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 197 t1 = e + e1(b) + Ch(b,c,d) + 0x34b0bcb5 + W[51]; 198 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 199 t1 = d + e1(a) + Ch(a,b,c) + 0x391c0cb3 + W[52]; 200 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 201 t1 = c + e1(h) + Ch(h,a,b) + 0x4ed8aa4a + W[53]; 202 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 203 t1 = b + e1(g) + Ch(g,h,a) + 0x5b9cca4f + W[54]; 204 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 205 t1 = a + e1(f) + Ch(f,g,h) + 0x682e6ff3 + W[55]; 206 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 207 208 t1 = h + e1(e) + Ch(e,f,g) + 0x748f82ee + W[56]; 209 t2 = e0(a) + Maj(a,b,c); d+=t1; h=t1+t2; 210 t1 = g + e1(d) + Ch(d,e,f) + 0x78a5636f + W[57]; 211 t2 = e0(h) + Maj(h,a,b); c+=t1; g=t1+t2; 212 t1 = f + e1(c) + Ch(c,d,e) + 0x84c87814 + W[58]; 213 t2 = e0(g) + Maj(g,h,a); b+=t1; f=t1+t2; 214 t1 = e + e1(b) + Ch(b,c,d) + 0x8cc70208 + W[59]; 215 t2 = e0(f) + Maj(f,g,h); a+=t1; e=t1+t2; 216 t1 = d + e1(a) + Ch(a,b,c) + 0x90befffa + W[60]; 217 t2 = e0(e) + Maj(e,f,g); h+=t1; d=t1+t2; 218 t1 = c + e1(h) + Ch(h,a,b) + 0xa4506ceb + W[61]; 219 t2 = e0(d) + Maj(d,e,f); g+=t1; c=t1+t2; 220 t1 = b + e1(g) + Ch(g,h,a) + 0xbef9a3f7 + W[62]; 221 t2 = e0(c) + Maj(c,d,e); f+=t1; b=t1+t2; 222 t1 = a + e1(f) + Ch(f,g,h) + 0xc67178f2 + W[63]; 223 t2 = e0(b) + Maj(b,c,d); e+=t1; a=t1+t2; 224 225 state[0] += a; state[1] += b; state[2] += c; state[3] += d; 226 state[4] += e; state[5] += f; state[6] += g; state[7] += h; 227 228 /* clear any sensitive info... */ 229 a = b = c = d = e = f = g = h = t1 = t2 = 0; 230 memset(W, 0, 64 * sizeof(u32)); 231 } 232 233 static void sha256_init(struct crypto_tfm *tfm) 234 { 235 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 236 sctx->state[0] = H0; 237 sctx->state[1] = H1; 238 sctx->state[2] = H2; 239 sctx->state[3] = H3; 240 sctx->state[4] = H4; 241 sctx->state[5] = H5; 242 sctx->state[6] = H6; 243 sctx->state[7] = H7; 244 sctx->count[0] = sctx->count[1] = 0; 245 } 246 247 static void sha256_update(struct crypto_tfm *tfm, const u8 *data, 248 unsigned int len) 249 { 250 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 251 unsigned int i, index, part_len; 252 253 /* Compute number of bytes mod 128 */ 254 index = (unsigned int)((sctx->count[0] >> 3) & 0x3f); 255 256 /* Update number of bits */ 257 if ((sctx->count[0] += (len << 3)) < (len << 3)) { 258 sctx->count[1]++; 259 sctx->count[1] += (len >> 29); 260 } 261 262 part_len = 64 - index; 263 264 /* Transform as many times as possible. */ 265 if (len >= part_len) { 266 memcpy(&sctx->buf[index], data, part_len); 267 sha256_transform(sctx->state, sctx->buf); 268 269 for (i = part_len; i + 63 < len; i += 64) 270 sha256_transform(sctx->state, &data[i]); 271 index = 0; 272 } else { 273 i = 0; 274 } 275 276 /* Buffer remaining input */ 277 memcpy(&sctx->buf[index], &data[i], len-i); 278 } 279 280 static void sha256_final(struct crypto_tfm *tfm, u8 *out) 281 { 282 struct sha256_ctx *sctx = crypto_tfm_ctx(tfm); 283 __be32 *dst = (__be32 *)out; 284 __be32 bits[2]; 285 unsigned int index, pad_len; 286 int i; 287 static const u8 padding[64] = { 0x80, }; 288 289 /* Save number of bits */ 290 bits[1] = cpu_to_be32(sctx->count[0]); 291 bits[0] = cpu_to_be32(sctx->count[1]); 292 293 /* Pad out to 56 mod 64. */ 294 index = (sctx->count[0] >> 3) & 0x3f; 295 pad_len = (index < 56) ? (56 - index) : ((64+56) - index); 296 sha256_update(tfm, padding, pad_len); 297 298 /* Append length (before padding) */ 299 sha256_update(tfm, (const u8 *)bits, sizeof(bits)); 300 301 /* Store state in digest */ 302 for (i = 0; i < 8; i++) 303 dst[i] = cpu_to_be32(sctx->state[i]); 304 305 /* Zeroize sensitive information. */ 306 memset(sctx, 0, sizeof(*sctx)); 307 } 308 309 310 static struct crypto_alg alg = { 311 .cra_name = "sha256", 312 .cra_driver_name= "sha256-generic", 313 .cra_flags = CRYPTO_ALG_TYPE_DIGEST, 314 .cra_blocksize = SHA256_HMAC_BLOCK_SIZE, 315 .cra_ctxsize = sizeof(struct sha256_ctx), 316 .cra_module = THIS_MODULE, 317 .cra_alignmask = 3, 318 .cra_list = LIST_HEAD_INIT(alg.cra_list), 319 .cra_u = { .digest = { 320 .dia_digestsize = SHA256_DIGEST_SIZE, 321 .dia_init = sha256_init, 322 .dia_update = sha256_update, 323 .dia_final = sha256_final } } 324 }; 325 326 static int __init init(void) 327 { 328 return crypto_register_alg(&alg); 329 } 330 331 static void __exit fini(void) 332 { 333 crypto_unregister_alg(&alg); 334 } 335 336 module_init(init); 337 module_exit(fini); 338 339 MODULE_LICENSE("GPL"); 340 MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm"); 341 342 MODULE_ALIAS("sha256-generic"); 343