| 1 | /************************* sha224-256.c ************************/ |
| 2 | /***************** See RFC 6234 for details. *******************/ |
| 3 | /* Copyright (c) 2011 IETF Trust and the persons identified as */ |
| 4 | /* authors of the code. All rights reserved. */ |
| 5 | /* See sha.h for terms of use and redistribution. */ |
| 6 | |
| 7 | /* |
| 8 | * Description: |
| 9 | * This file implements the Secure Hash Algorithms SHA-224 and |
| 10 | * SHA-256 as defined in the U.S. National Institute of Standards |
| 11 | * and Technology Federal Information Processing Standards |
| 12 | * Publication (FIPS PUB) 180-3 published in October 2008 |
| 13 | * and formerly defined in its predecessors, FIPS PUB 180-1 |
| 14 | * and FIP PUB 180-2. |
| 15 | * |
| 16 | * A combined document showing all algorithms is available at |
| 17 | * http://csrc.nist.gov/publications/fips/ |
| 18 | * fips180-3/fips180-3_final.pdf |
| 19 | * |
| 20 | * The SHA-224 and SHA-256 algorithms produce 224-bit and 256-bit |
| 21 | * message digests for a given data stream. It should take about |
| 22 | * 2**n steps to find a message with the same digest as a given |
| 23 | * message and 2**(n/2) to find any two messages with the same |
| 24 | * digest, when n is the digest size in bits. Therefore, this |
| 25 | * algorithm can serve as a means of providing a |
| 26 | * "fingerprint" for a message. |
| 27 | * |
| 28 | * Portability Issues: |
| 29 | * SHA-224 and SHA-256 are defined in terms of 32-bit "words". |
| 30 | * This code uses <stdint.h> (included via "sha.h") to define 32- |
| 31 | * and 8-bit unsigned integer types. If your C compiler does not |
| 32 | * support 32-bit unsigned integers, this code is not |
| 33 | * appropriate. |
| 34 | * |
| 35 | * Caveats: |
| 36 | * SHA-224 and SHA-256 are designed to work with messages less |
| 37 | * than 2^64 bits long. This implementation uses SHA224/256Input() |
| 38 | * to hash the bits that are a multiple of the size of an 8-bit |
| 39 | * octet, and then optionally uses SHA224/256FinalBits() |
| 40 | * to hash the final few bits of the input. |
| 41 | */ |
| 42 | |
| 43 | #include "sha.h" |
| 44 | #include "sha-private.h" |
| 45 | |
| 46 | /* Define the SHA shift, rotate left, and rotate right macros */ |
| 47 | #define SHA256_SHR(bits,word) ((word) >> (bits)) |
| 48 | #define SHA256_ROTL(bits,word) \ |
| 49 | (((word) << (bits)) | ((word) >> (32-(bits)))) |
| 50 | #define SHA256_ROTR(bits,word) \ |
| 51 | (((word) >> (bits)) | ((word) << (32-(bits)))) |
| 52 | |
| 53 | /* Define the SHA SIGMA and sigma macros */ |
| 54 | #define SHA256_SIGMA0(word) \ |
| 55 | (SHA256_ROTR( 2,word) ^ SHA256_ROTR(13,word) ^ SHA256_ROTR(22,word)) |
| 56 | #define SHA256_SIGMA1(word) \ |
| 57 | (SHA256_ROTR( 6,word) ^ SHA256_ROTR(11,word) ^ SHA256_ROTR(25,word)) |
| 58 | #define SHA256_sigma0(word) \ |
| 59 | (SHA256_ROTR( 7,word) ^ SHA256_ROTR(18,word) ^ SHA256_SHR( 3,word)) |
| 60 | #define SHA256_sigma1(word) \ |
| 61 | (SHA256_ROTR(17,word) ^ SHA256_ROTR(19,word) ^ SHA256_SHR(10,word)) |
| 62 | |
| 63 | /* |
| 64 | * Add "length" to the length. |
| 65 | * Set Corrupted when overflow has occurred. |
| 66 | */ |
| 67 | /* addTemp commented out by Nokia, static variables are not thread-safe */ |
| 68 | /* static uint32_t addTemp; */ |
| 69 | /* 'M' appended to Macro name by Nokia */ |
| 70 | #define SHA224_256AddLengthM(context, length) \ |
| 71 | (addTemp = (context)->Length_Low, (context)->Corrupted = \ |
| 72 | (((context)->Length_Low += (length)) < addTemp) && \ |
| 73 | (++(context)->Length_High == 0) ? shaInputTooLong : \ |
| 74 | (context)->Corrupted ) |
| 75 | |
| 76 | /* Local Function Prototypes */ |
| 77 | static int SHA224_256Reset(SHA256Context *context, uint32_t *H0); |
| 78 | static void SHA224_256ProcessMessageBlock(SHA256Context *context); |
| 79 | static void SHA224_256Finalize(SHA256Context *context, |
| 80 | uint8_t Pad_Byte); |
| 81 | static void SHA224_256PadMessage(SHA256Context *context, |
| 82 | uint8_t Pad_Byte); |
| 83 | static int SHA224_256ResultN(SHA256Context *context, |
| 84 | uint8_t Message_Digest[ ], int HashSize); |
| 85 | |
| 86 | /* Initial Hash Values: FIPS 180-3 section 5.3.2 */ |
| 87 | static uint32_t SHA224_H0[SHA256HashSize/4] = { |
| 88 | 0xC1059ED8, 0x367CD507, 0x3070DD17, 0xF70E5939, |
| 89 | 0xFFC00B31, 0x68581511, 0x64F98FA7, 0xBEFA4FA4 |
| 90 | }; |
| 91 | |
| 92 | /* Initial Hash Values: FIPS 180-3 section 5.3.3 */ |
| 93 | static uint32_t SHA256_H0[SHA256HashSize/4] = { |
| 94 | 0x6A09E667, 0xBB67AE85, 0x3C6EF372, 0xA54FF53A, |
| 95 | 0x510E527F, 0x9B05688C, 0x1F83D9AB, 0x5BE0CD19 |
| 96 | }; |
| 97 | |
| 98 | /* |
| 99 | * SHA224Reset |
| 100 | * |
| 101 | * Description: |
| 102 | * This function will initialize the SHA224Context in preparation |
| 103 | * for computing a new SHA224 message digest. |
| 104 | * |
| 105 | * Parameters: |
| 106 | * context: [in/out] |
| 107 | * The context to reset. |
| 108 | * |
| 109 | * Returns: |
| 110 | * sha Error Code. |
| 111 | */ |
| 112 | int SHA224Reset(SHA224Context *context) |
| 113 | { |
| 114 | return SHA224_256Reset(context, H0: SHA224_H0); |
| 115 | } |
| 116 | |
| 117 | /* |
| 118 | * SHA224Input |
| 119 | * |
| 120 | * Description: |
| 121 | * This function accepts an array of octets as the next portion |
| 122 | * of the message. |
| 123 | * |
| 124 | * Parameters: |
| 125 | * context: [in/out] |
| 126 | * The SHA context to update. |
| 127 | * message_array[ ]: [in] |
| 128 | * An array of octets representing the next portion of |
| 129 | * the message. |
| 130 | * length: [in] |
| 131 | * The length of the message in message_array. |
| 132 | * |
| 133 | * Returns: |
| 134 | * sha Error Code. |
| 135 | * |
| 136 | */ |
| 137 | int SHA224Input(SHA224Context *context, const uint8_t *message_array, |
| 138 | unsigned int length) |
| 139 | { |
| 140 | return SHA256Input(context, bytes: message_array, bytecount: length); |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * SHA224FinalBits |
| 145 | * |
| 146 | * Description: |
| 147 | * This function will add in any final bits of the message. |
| 148 | * |
| 149 | * Parameters: |
| 150 | * context: [in/out] |
| 151 | * The SHA context to update. |
| 152 | * message_bits: [in] |
| 153 | * The final bits of the message, in the upper portion of the |
| 154 | * byte. (Use 0b###00000 instead of 0b00000### to input the |
| 155 | * three bits ###.) |
| 156 | * length: [in] |
| 157 | * The number of bits in message_bits, between 1 and 7. |
| 158 | * |
| 159 | * Returns: |
| 160 | * sha Error Code. |
| 161 | */ |
| 162 | int SHA224FinalBits(SHA224Context *context, |
| 163 | uint8_t message_bits, unsigned int length) |
| 164 | { |
| 165 | return SHA256FinalBits(context, bits: message_bits, bit_count: length); |
| 166 | } |
| 167 | |
| 168 | /* |
| 169 | * SHA224Result |
| 170 | * |
| 171 | * Description: |
| 172 | * This function will return the 224-bit message digest |
| 173 | * into the Message_Digest array provided by the caller. |
| 174 | * NOTE: |
| 175 | * The first octet of hash is stored in the element with index 0, |
| 176 | * the last octet of hash in the element with index 27. |
| 177 | * |
| 178 | * Parameters: |
| 179 | * context: [in/out] |
| 180 | * The context to use to calculate the SHA hash. |
| 181 | * Message_Digest[ ]: [out] |
| 182 | * Where the digest is returned. |
| 183 | * |
| 184 | * Returns: |
| 185 | * sha Error Code. |
| 186 | */ |
| 187 | int SHA224Result(SHA224Context *context, |
| 188 | uint8_t Message_Digest[SHA224HashSize]) |
| 189 | { |
| 190 | return SHA224_256ResultN(context, Message_Digest, HashSize: SHA224HashSize); |
| 191 | } |
| 192 | |
| 193 | /* |
| 194 | * SHA256Reset |
| 195 | * |
| 196 | * Description: |
| 197 | * This function will initialize the SHA256Context in preparation |
| 198 | * for computing a new SHA256 message digest. |
| 199 | * |
| 200 | * Parameters: |
| 201 | * context: [in/out] |
| 202 | * The context to reset. |
| 203 | * |
| 204 | * Returns: |
| 205 | * sha Error Code. |
| 206 | */ |
| 207 | int SHA256Reset(SHA256Context *context) |
| 208 | { |
| 209 | return SHA224_256Reset(context, H0: SHA256_H0); |
| 210 | } |
| 211 | |
| 212 | /* |
| 213 | * SHA256Input |
| 214 | * |
| 215 | * Description: |
| 216 | * This function accepts an array of octets as the next portion |
| 217 | * of the message. |
| 218 | * |
| 219 | * Parameters: |
| 220 | * context: [in/out] |
| 221 | * The SHA context to update. |
| 222 | * message_array[ ]: [in] |
| 223 | * An array of octets representing the next portion of |
| 224 | * the message. |
| 225 | * length: [in] |
| 226 | * The length of the message in message_array. |
| 227 | * |
| 228 | * Returns: |
| 229 | * sha Error Code. |
| 230 | */ |
| 231 | int SHA256Input(SHA256Context *context, const uint8_t *message_array, |
| 232 | unsigned int length) |
| 233 | { |
| 234 | if (!context) return shaNull; |
| 235 | if (!length) return shaSuccess; |
| 236 | if (!message_array) return shaNull; |
| 237 | if (context->Computed) return context->Corrupted = shaStateError; |
| 238 | if (context->Corrupted) return context->Corrupted; |
| 239 | |
| 240 | while (length--) { |
| 241 | context->Message_Block[context->Message_Block_Index++] = |
| 242 | *message_array; |
| 243 | |
| 244 | if ((SHA224_256AddLength(context, length: 8) == shaSuccess) && |
| 245 | (context->Message_Block_Index == SHA256_Message_Block_Size)) |
| 246 | SHA224_256ProcessMessageBlock(context); |
| 247 | |
| 248 | message_array++; |
| 249 | } |
| 250 | |
| 251 | return context->Corrupted; |
| 252 | |
| 253 | } |
| 254 | |
| 255 | /* |
| 256 | * SHA256FinalBits |
| 257 | * |
| 258 | * Description: |
| 259 | * This function will add in any final bits of the message. |
| 260 | * |
| 261 | * Parameters: |
| 262 | * context: [in/out] |
| 263 | * The SHA context to update. |
| 264 | * message_bits: [in] |
| 265 | * The final bits of the message, in the upper portion of the |
| 266 | * byte. (Use 0b###00000 instead of 0b00000### to input the |
| 267 | * three bits ###.) |
| 268 | * length: [in] |
| 269 | * The number of bits in message_bits, between 1 and 7. |
| 270 | * |
| 271 | * Returns: |
| 272 | * sha Error Code. |
| 273 | */ |
| 274 | int SHA256FinalBits(SHA256Context *context, |
| 275 | uint8_t message_bits, unsigned int length) |
| 276 | { |
| 277 | static uint8_t masks[8] = { |
| 278 | /* 0 0b00000000 */ 0x00, /* 1 0b10000000 */ 0x80, |
| 279 | /* 2 0b11000000 */ 0xC0, /* 3 0b11100000 */ 0xE0, |
| 280 | /* 4 0b11110000 */ 0xF0, /* 5 0b11111000 */ 0xF8, |
| 281 | /* 6 0b11111100 */ 0xFC, /* 7 0b11111110 */ 0xFE |
| 282 | }; |
| 283 | static uint8_t markbit[8] = { |
| 284 | /* 0 0b10000000 */ 0x80, /* 1 0b01000000 */ 0x40, |
| 285 | /* 2 0b00100000 */ 0x20, /* 3 0b00010000 */ 0x10, |
| 286 | /* 4 0b00001000 */ 0x08, /* 5 0b00000100 */ 0x04, |
| 287 | /* 6 0b00000010 */ 0x02, /* 7 0b00000001 */ 0x01 |
| 288 | }; |
| 289 | |
| 290 | if (!context) return shaNull; |
| 291 | if (!length) return shaSuccess; |
| 292 | if (context->Corrupted) return context->Corrupted; |
| 293 | if (context->Computed) return context->Corrupted = shaStateError; |
| 294 | if (length >= 8) return context->Corrupted = shaBadParam; |
| 295 | |
| 296 | SHA224_256AddLength(context, length); |
| 297 | SHA224_256Finalize(context, Pad_Byte: (uint8_t) |
| 298 | ((message_bits & masks[length]) | markbit[length])); |
| 299 | |
| 300 | return context->Corrupted; |
| 301 | } |
| 302 | |
| 303 | /* |
| 304 | * SHA256Result |
| 305 | * |
| 306 | * Description: |
| 307 | * This function will return the 256-bit message digest |
| 308 | * into the Message_Digest array provided by the caller. |
| 309 | * NOTE: |
| 310 | * The first octet of hash is stored in the element with index 0, |
| 311 | * the last octet of hash in the element with index 31. |
| 312 | * |
| 313 | * Parameters: |
| 314 | * context: [in/out] |
| 315 | * The context to use to calculate the SHA hash. |
| 316 | * Message_Digest[ ]: [out] |
| 317 | * Where the digest is returned. |
| 318 | * |
| 319 | * Returns: |
| 320 | * sha Error Code. |
| 321 | */ |
| 322 | int SHA256Result(SHA256Context *context, |
| 323 | uint8_t Message_Digest[SHA256HashSize]) |
| 324 | { |
| 325 | return SHA224_256ResultN(context, Message_Digest, HashSize: SHA256HashSize); |
| 326 | } |
| 327 | |
| 328 | /* |
| 329 | * SHA224_256Reset |
| 330 | * |
| 331 | * Description: |
| 332 | * This helper function will initialize the SHA256Context in |
| 333 | * preparation for computing a new SHA-224 or SHA-256 message digest. |
| 334 | * |
| 335 | * Parameters: |
| 336 | * context: [in/out] |
| 337 | * The context to reset. |
| 338 | * H0[ ]: [in] |
| 339 | * The initial hash value array to use. |
| 340 | * |
| 341 | * Returns: |
| 342 | * sha Error Code. |
| 343 | */ |
| 344 | static int SHA224_256Reset(SHA256Context *context, uint32_t *H0) |
| 345 | { |
| 346 | if (!context) return shaNull; |
| 347 | |
| 348 | context->Length_High = context->Length_Low = 0; |
| 349 | context->Message_Block_Index = 0; |
| 350 | |
| 351 | context->Intermediate_Hash[0] = H0[0]; |
| 352 | context->Intermediate_Hash[1] = H0[1]; |
| 353 | context->Intermediate_Hash[2] = H0[2]; |
| 354 | context->Intermediate_Hash[3] = H0[3]; |
| 355 | context->Intermediate_Hash[4] = H0[4]; |
| 356 | context->Intermediate_Hash[5] = H0[5]; |
| 357 | context->Intermediate_Hash[6] = H0[6]; |
| 358 | context->Intermediate_Hash[7] = H0[7]; |
| 359 | |
| 360 | context->Computed = 0; |
| 361 | context->Corrupted = shaSuccess; |
| 362 | |
| 363 | return shaSuccess; |
| 364 | } |
| 365 | |
| 366 | /* |
| 367 | * SHA224_256ProcessMessageBlock |
| 368 | * |
| 369 | * Description: |
| 370 | * This helper function will process the next 512 bits of the |
| 371 | * message stored in the Message_Block array. |
| 372 | * |
| 373 | * Parameters: |
| 374 | * context: [in/out] |
| 375 | * The SHA context to update. |
| 376 | * |
| 377 | * Returns: |
| 378 | * Nothing. |
| 379 | * |
| 380 | * Comments: |
| 381 | * Many of the variable names in this code, especially the |
| 382 | * single character names, were used because those were the |
| 383 | * names used in the Secure Hash Standard. |
| 384 | */ |
| 385 | static void SHA224_256ProcessMessageBlock(SHA256Context *context) |
| 386 | { |
| 387 | /* Constants defined in FIPS 180-3, section 4.2.2 */ |
| 388 | static const uint32_t K[64] = { |
| 389 | 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, |
| 390 | 0x59f111f1, 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, |
| 391 | 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, |
| 392 | 0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, |
| 393 | 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152, |
| 394 | 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, |
| 395 | 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, |
| 396 | 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, |
| 397 | 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, |
| 398 | 0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116, 0x1e376c08, |
| 399 | 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, |
| 400 | 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, |
| 401 | 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 |
| 402 | }; |
| 403 | int t, t4; /* Loop counter */ |
| 404 | uint32_t temp1, temp2; /* Temporary word value */ |
| 405 | uint32_t W[64]; /* Word sequence */ |
| 406 | uint32_t A, B, C, D, E, F, G, H; /* Word buffers */ |
| 407 | |
| 408 | /* |
| 409 | * Initialize the first 16 words in the array W |
| 410 | */ |
| 411 | for (t = t4 = 0; t < 16; t++, t4 += 4) |
| 412 | W[t] = (((uint32_t)context->Message_Block[t4]) << 24) | |
| 413 | (((uint32_t)context->Message_Block[t4 + 1]) << 16) | |
| 414 | (((uint32_t)context->Message_Block[t4 + 2]) << 8) | |
| 415 | (((uint32_t)context->Message_Block[t4 + 3])); |
| 416 | |
| 417 | for (t = 16; t < 64; t++) |
| 418 | W[t] = SHA256_sigma1(W[t-2]) + W[t-7] + |
| 419 | SHA256_sigma0(W[t-15]) + W[t-16]; |
| 420 | |
| 421 | A = context->Intermediate_Hash[0]; |
| 422 | B = context->Intermediate_Hash[1]; |
| 423 | C = context->Intermediate_Hash[2]; |
| 424 | D = context->Intermediate_Hash[3]; |
| 425 | E = context->Intermediate_Hash[4]; |
| 426 | F = context->Intermediate_Hash[5]; |
| 427 | G = context->Intermediate_Hash[6]; |
| 428 | H = context->Intermediate_Hash[7]; |
| 429 | |
| 430 | for (t = 0; t < 64; t++) { |
| 431 | temp1 = H + SHA256_SIGMA1(E) + SHA_Ch(E,F,G) + K[t] + W[t]; |
| 432 | temp2 = SHA256_SIGMA0(A) + SHA_Maj(A,B,C); |
| 433 | H = G; |
| 434 | G = F; |
| 435 | F = E; |
| 436 | E = D + temp1; |
| 437 | D = C; |
| 438 | C = B; |
| 439 | B = A; |
| 440 | A = temp1 + temp2; |
| 441 | } |
| 442 | |
| 443 | context->Intermediate_Hash[0] += A; |
| 444 | context->Intermediate_Hash[1] += B; |
| 445 | context->Intermediate_Hash[2] += C; |
| 446 | context->Intermediate_Hash[3] += D; |
| 447 | context->Intermediate_Hash[4] += E; |
| 448 | context->Intermediate_Hash[5] += F; |
| 449 | context->Intermediate_Hash[6] += G; |
| 450 | context->Intermediate_Hash[7] += H; |
| 451 | |
| 452 | context->Message_Block_Index = 0; |
| 453 | } |
| 454 | |
| 455 | /* |
| 456 | * SHA224_256Finalize |
| 457 | * |
| 458 | * Description: |
| 459 | * This helper function finishes off the digest calculations. |
| 460 | * |
| 461 | * Parameters: |
| 462 | * context: [in/out] |
| 463 | * The SHA context to update. |
| 464 | * Pad_Byte: [in] |
| 465 | * The last byte to add to the message block before the 0-padding |
| 466 | * and length. This will contain the last bits of the message |
| 467 | * followed by another single bit. If the message was an |
| 468 | * exact multiple of 8-bits long, Pad_Byte will be 0x80. |
| 469 | * |
| 470 | * Returns: |
| 471 | * sha Error Code. |
| 472 | */ |
| 473 | static void SHA224_256Finalize(SHA256Context *context, |
| 474 | uint8_t Pad_Byte) |
| 475 | { |
| 476 | int i; |
| 477 | SHA224_256PadMessage(context, Pad_Byte); |
| 478 | /* message may be sensitive, so clear it out */ |
| 479 | for (i = 0; i < SHA256_Message_Block_Size; ++i) |
| 480 | context->Message_Block[i] = 0; |
| 481 | context->Length_High = 0; /* and clear length */ |
| 482 | context->Length_Low = 0; |
| 483 | context->Computed = 1; |
| 484 | } |
| 485 | |
| 486 | /* |
| 487 | * SHA224_256PadMessage |
| 488 | * |
| 489 | * Description: |
| 490 | * According to the standard, the message must be padded to the next |
| 491 | * even multiple of 512 bits. The first padding bit must be a '1'. |
| 492 | * The last 64 bits represent the length of the original message. |
| 493 | * All bits in between should be 0. This helper function will pad |
| 494 | * the message according to those rules by filling the |
| 495 | * Message_Block array accordingly. When it returns, it can be |
| 496 | * assumed that the message digest has been computed. |
| 497 | * |
| 498 | * Parameters: |
| 499 | * context: [in/out] |
| 500 | * The context to pad. |
| 501 | * Pad_Byte: [in] |
| 502 | * The last byte to add to the message block before the 0-padding |
| 503 | * and length. This will contain the last bits of the message |
| 504 | * followed by another single bit. If the message was an |
| 505 | * exact multiple of 8-bits long, Pad_Byte will be 0x80. |
| 506 | * |
| 507 | * Returns: |
| 508 | * Nothing. |
| 509 | */ |
| 510 | static void SHA224_256PadMessage(SHA256Context *context, |
| 511 | uint8_t Pad_Byte) |
| 512 | { |
| 513 | /* |
| 514 | * Check to see if the current message block is too small to hold |
| 515 | * the initial padding bits and length. If so, we will pad the |
| 516 | * block, process it, and then continue padding into a second |
| 517 | * block. |
| 518 | */ |
| 519 | if (context->Message_Block_Index >= (SHA256_Message_Block_Size-8)) { |
| 520 | context->Message_Block[context->Message_Block_Index++] = Pad_Byte; |
| 521 | while (context->Message_Block_Index < SHA256_Message_Block_Size) |
| 522 | context->Message_Block[context->Message_Block_Index++] = 0; |
| 523 | SHA224_256ProcessMessageBlock(context); |
| 524 | } else |
| 525 | context->Message_Block[context->Message_Block_Index++] = Pad_Byte; |
| 526 | |
| 527 | while (context->Message_Block_Index < (SHA256_Message_Block_Size-8)) |
| 528 | context->Message_Block[context->Message_Block_Index++] = 0; |
| 529 | |
| 530 | /* |
| 531 | * Store the message length as the last 8 octets |
| 532 | */ |
| 533 | context->Message_Block[56] = (uint8_t)(context->Length_High >> 24); |
| 534 | context->Message_Block[57] = (uint8_t)(context->Length_High >> 16); |
| 535 | context->Message_Block[58] = (uint8_t)(context->Length_High >> 8); |
| 536 | context->Message_Block[59] = (uint8_t)(context->Length_High); |
| 537 | context->Message_Block[60] = (uint8_t)(context->Length_Low >> 24); |
| 538 | context->Message_Block[61] = (uint8_t)(context->Length_Low >> 16); |
| 539 | context->Message_Block[62] = (uint8_t)(context->Length_Low >> 8); |
| 540 | context->Message_Block[63] = (uint8_t)(context->Length_Low); |
| 541 | |
| 542 | SHA224_256ProcessMessageBlock(context); |
| 543 | } |
| 544 | |
| 545 | /* |
| 546 | * SHA224_256ResultN |
| 547 | * |
| 548 | * Description: |
| 549 | * This helper function will return the 224-bit or 256-bit message |
| 550 | * digest into the Message_Digest array provided by the caller. |
| 551 | * NOTE: |
| 552 | * The first octet of hash is stored in the element with index 0, |
| 553 | * the last octet of hash in the element with index 27/31. |
| 554 | * |
| 555 | * Parameters: |
| 556 | * context: [in/out] |
| 557 | * The context to use to calculate the SHA hash. |
| 558 | * Message_Digest[ ]: [out] |
| 559 | * Where the digest is returned. |
| 560 | * HashSize: [in] |
| 561 | * The size of the hash, either 28 or 32. |
| 562 | * |
| 563 | * Returns: |
| 564 | * sha Error Code. |
| 565 | */ |
| 566 | static int SHA224_256ResultN(SHA256Context *context, |
| 567 | uint8_t Message_Digest[ ], int HashSize) |
| 568 | { |
| 569 | int i; |
| 570 | |
| 571 | if (!context) return shaNull; |
| 572 | if (!Message_Digest) return shaNull; |
| 573 | if (context->Corrupted) return context->Corrupted; |
| 574 | |
| 575 | if (!context->Computed) |
| 576 | SHA224_256Finalize(context, Pad_Byte: 0x80); |
| 577 | |
| 578 | for (i = 0; i < HashSize; ++i) |
| 579 | Message_Digest[i] = (uint8_t) |
| 580 | (context->Intermediate_Hash[i>>2] >> 8 * ( 3 - ( i & 0x03 ) )); |
| 581 | |
| 582 | return shaSuccess; |
| 583 | } |
| 584 | |