| 1 | /* |
| 2 | * Copyright (c) 2007, Cameron Rich |
| 3 | * |
| 4 | * All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions are met: |
| 8 | * |
| 9 | * * Redistributions of source code must retain the above copyright notice, |
| 10 | * this list of conditions and the following disclaimer. |
| 11 | * * Redistributions in binary form must reproduce the above copyright notice, |
| 12 | * this list of conditions and the following disclaimer in the documentation |
| 13 | * and/or other materials provided with the distribution. |
| 14 | * * Neither the name of the axTLS project nor the names of its contributors |
| 15 | * may be used to endorse or promote products derived from this software |
| 16 | * without specific prior written permission. |
| 17 | * |
| 18 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| 19 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| 20 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| 21 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| 22 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 23 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 24 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| 25 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| 26 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| 27 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| 28 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | */ |
| 30 | |
| 31 | /** |
| 32 | * SHA1 implementation - as defined in FIPS PUB 180-1 published April 17, 1995. |
| 33 | * This code was originally taken from RFC3174 |
| 34 | */ |
| 35 | |
| 36 | #include <string.h> |
| 37 | #include "os_port.h" |
| 38 | #include "crypto.h" |
| 39 | |
| 40 | /* |
| 41 | * Define the SHA1 circular left shift macro |
| 42 | */ |
| 43 | #define SHA1CircularShift(bits,word) \ |
| 44 | (((word) << (bits)) | ((word) >> (32-(bits)))) |
| 45 | |
| 46 | /* ----- static functions ----- */ |
| 47 | static void SHA1PadMessage(SHA1_CTX *ctx); |
| 48 | static void SHA1ProcessMessageBlock(SHA1_CTX *ctx); |
| 49 | |
| 50 | /** |
| 51 | * Initialize the SHA1 context |
| 52 | */ |
| 53 | void SHA1_Init(SHA1_CTX *ctx) |
| 54 | { |
| 55 | ctx->Length_Low = 0; |
| 56 | ctx->Length_High = 0; |
| 57 | ctx->Message_Block_Index = 0; |
| 58 | ctx->Intermediate_Hash[0] = 0x67452301; |
| 59 | ctx->Intermediate_Hash[1] = 0xEFCDAB89; |
| 60 | ctx->Intermediate_Hash[2] = 0x98BADCFE; |
| 61 | ctx->Intermediate_Hash[3] = 0x10325476; |
| 62 | ctx->Intermediate_Hash[4] = 0xC3D2E1F0; |
| 63 | } |
| 64 | |
| 65 | /** |
| 66 | * Accepts an array of octets as the next portion of the message. |
| 67 | */ |
| 68 | void SHA1_Update(SHA1_CTX *ctx, const uint8_t *msg, int len) |
| 69 | { |
| 70 | while (len--) |
| 71 | { |
| 72 | ctx->Message_Block[ctx->Message_Block_Index++] = (*msg & 0xFF); |
| 73 | ctx->Length_Low += 8; |
| 74 | |
| 75 | if (ctx->Length_Low == 0) |
| 76 | ctx->Length_High++; |
| 77 | |
| 78 | if (ctx->Message_Block_Index == 64) |
| 79 | SHA1ProcessMessageBlock(ctx); |
| 80 | |
| 81 | msg++; |
| 82 | } |
| 83 | } |
| 84 | |
| 85 | /** |
| 86 | * Return the 160-bit message digest into the user's array |
| 87 | */ |
| 88 | void SHA1_Final(uint8_t *digest, SHA1_CTX *ctx) |
| 89 | { |
| 90 | int i; |
| 91 | |
| 92 | SHA1PadMessage(ctx); |
| 93 | memset(ctx->Message_Block, 0, 64); |
| 94 | ctx->Length_Low = 0; /* and clear length */ |
| 95 | ctx->Length_High = 0; |
| 96 | |
| 97 | for (i = 0; i < SHA1_SIZE; i++) |
| 98 | { |
| 99 | digest[i] = ctx->Intermediate_Hash[i>>2] >> 8 * ( 3 - ( i & 0x03 ) ); |
| 100 | } |
| 101 | } |
| 102 | |
| 103 | /** |
| 104 | * Process the next 512 bits of the message stored in the array. |
| 105 | */ |
| 106 | static void SHA1ProcessMessageBlock(SHA1_CTX *ctx) |
| 107 | { |
| 108 | const uint32_t K[] = { /* Constants defined in SHA-1 */ |
| 109 | 0x5A827999, |
| 110 | 0x6ED9EBA1, |
| 111 | 0x8F1BBCDC, |
| 112 | 0xCA62C1D6 |
| 113 | }; |
| 114 | int t; /* Loop counter */ |
| 115 | uint32_t temp; /* Temporary word value */ |
| 116 | uint32_t W[80]; /* Word sequence */ |
| 117 | uint32_t A, B, C, D, E; /* Word buffers */ |
| 118 | |
| 119 | /* |
| 120 | * Initialize the first 16 words in the array W |
| 121 | */ |
| 122 | for (t = 0; t < 16; t++) |
| 123 | { |
| 124 | W[t] = ctx->Message_Block[t * 4] << 24; |
| 125 | W[t] |= ctx->Message_Block[t * 4 + 1] << 16; |
| 126 | W[t] |= ctx->Message_Block[t * 4 + 2] << 8; |
| 127 | W[t] |= ctx->Message_Block[t * 4 + 3]; |
| 128 | } |
| 129 | |
| 130 | for (t = 16; t < 80; t++) |
| 131 | { |
| 132 | W[t] = SHA1CircularShift(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]); |
| 133 | } |
| 134 | |
| 135 | A = ctx->Intermediate_Hash[0]; |
| 136 | B = ctx->Intermediate_Hash[1]; |
| 137 | C = ctx->Intermediate_Hash[2]; |
| 138 | D = ctx->Intermediate_Hash[3]; |
| 139 | E = ctx->Intermediate_Hash[4]; |
| 140 | |
| 141 | for (t = 0; t < 20; t++) |
| 142 | { |
| 143 | temp = SHA1CircularShift(5,A) + |
| 144 | ((B & C) | ((~B) & D)) + E + W[t] + K[0]; |
| 145 | E = D; |
| 146 | D = C; |
| 147 | C = SHA1CircularShift(30,B); |
| 148 | |
| 149 | B = A; |
| 150 | A = temp; |
| 151 | } |
| 152 | |
| 153 | for (t = 20; t < 40; t++) |
| 154 | { |
| 155 | temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[1]; |
| 156 | E = D; |
| 157 | D = C; |
| 158 | C = SHA1CircularShift(30,B); |
| 159 | B = A; |
| 160 | A = temp; |
| 161 | } |
| 162 | |
| 163 | for (t = 40; t < 60; t++) |
| 164 | { |
| 165 | temp = SHA1CircularShift(5,A) + |
| 166 | ((B & C) | (B & D) | (C & D)) + E + W[t] + K[2]; |
| 167 | E = D; |
| 168 | D = C; |
| 169 | C = SHA1CircularShift(30,B); |
| 170 | B = A; |
| 171 | A = temp; |
| 172 | } |
| 173 | |
| 174 | for (t = 60; t < 80; t++) |
| 175 | { |
| 176 | temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[3]; |
| 177 | E = D; |
| 178 | D = C; |
| 179 | C = SHA1CircularShift(30,B); |
| 180 | B = A; |
| 181 | A = temp; |
| 182 | } |
| 183 | |
| 184 | ctx->Intermediate_Hash[0] += A; |
| 185 | ctx->Intermediate_Hash[1] += B; |
| 186 | ctx->Intermediate_Hash[2] += C; |
| 187 | ctx->Intermediate_Hash[3] += D; |
| 188 | ctx->Intermediate_Hash[4] += E; |
| 189 | ctx->Message_Block_Index = 0; |
| 190 | } |
| 191 | |
| 192 | /* |
| 193 | * According to the standard, the message must be padded to an even |
| 194 | * 512 bits. The first padding bit must be a '1'. The last 64 |
| 195 | * bits represent the length of the original message. All bits in |
| 196 | * between should be 0. This function will pad the message |
| 197 | * according to those rules by filling the Message_Block array |
| 198 | * accordingly. It will also call the ProcessMessageBlock function |
| 199 | * provided appropriately. When it returns, it can be assumed that |
| 200 | * the message digest has been computed. |
| 201 | * |
| 202 | * @param ctx [in, out] The SHA1 context |
| 203 | */ |
| 204 | static void SHA1PadMessage(SHA1_CTX *ctx) |
| 205 | { |
| 206 | /* |
| 207 | * Check to see if the current message block is too small to hold |
| 208 | * the initial padding bits and length. If so, we will pad the |
| 209 | * block, process it, and then continue padding into a second |
| 210 | * block. |
| 211 | */ |
| 212 | if (ctx->Message_Block_Index > 55) |
| 213 | { |
| 214 | ctx->Message_Block[ctx->Message_Block_Index++] = 0x80; |
| 215 | while(ctx->Message_Block_Index < 64) |
| 216 | { |
| 217 | ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| 218 | } |
| 219 | |
| 220 | SHA1ProcessMessageBlock(ctx); |
| 221 | |
| 222 | while (ctx->Message_Block_Index < 56) |
| 223 | { |
| 224 | ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| 225 | } |
| 226 | } |
| 227 | else |
| 228 | { |
| 229 | ctx->Message_Block[ctx->Message_Block_Index++] = 0x80; |
| 230 | while(ctx->Message_Block_Index < 56) |
| 231 | { |
| 232 | |
| 233 | ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| 234 | } |
| 235 | } |
| 236 | |
| 237 | /* |
| 238 | * Store the message length as the last 8 octets |
| 239 | */ |
| 240 | ctx->Message_Block[56] = ctx->Length_High >> 24; |
| 241 | ctx->Message_Block[57] = ctx->Length_High >> 16; |
| 242 | ctx->Message_Block[58] = ctx->Length_High >> 8; |
| 243 | ctx->Message_Block[59] = ctx->Length_High; |
| 244 | ctx->Message_Block[60] = ctx->Length_Low >> 24; |
| 245 | ctx->Message_Block[61] = ctx->Length_Low >> 16; |
| 246 | ctx->Message_Block[62] = ctx->Length_Low >> 8; |
| 247 | ctx->Message_Block[63] = ctx->Length_Low; |
| 248 | SHA1ProcessMessageBlock(ctx); |
| 249 | } |