| /* |
| * Copyright(C) 2006 Cameron Rich |
| * |
| * This library is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU Lesser General Public License as published by |
| * the Free Software Foundation; either version 2.1 of the License, or |
| * (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public License |
| * along with this library; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| /** |
| * SHA1 implementation - as defined in FIPS PUB 180-1 published April 17, 1995. |
| * This code was originally taken from RFC3174 |
| */ |
| |
| #include <string.h> |
| #include "crypto.h" |
| |
| /* |
| * Define the SHA1 circular left shift macro |
| */ |
| #define SHA1CircularShift(bits,word) \ |
| (((word) << (bits)) | ((word) >> (32-(bits)))) |
| |
| /* ----- static functions ----- */ |
| static void SHA1PadMessage(SHA1_CTX *ctx); |
| static void SHA1ProcessMessageBlock(SHA1_CTX *ctx); |
| |
| /** |
| * Initialize the SHA1 context |
| */ |
| void SHA1Init(SHA1_CTX *ctx) |
| { |
| ctx->Length_Low = 0; |
| ctx->Length_High = 0; |
| ctx->Message_Block_Index = 0; |
| ctx->Intermediate_Hash[0] = 0x67452301; |
| ctx->Intermediate_Hash[1] = 0xEFCDAB89; |
| ctx->Intermediate_Hash[2] = 0x98BADCFE; |
| ctx->Intermediate_Hash[3] = 0x10325476; |
| ctx->Intermediate_Hash[4] = 0xC3D2E1F0; |
| } |
| |
| /** |
| * Accepts an array of octets as the next portion of the message. |
| */ |
| void SHA1Update(SHA1_CTX *ctx, const uint8_t *msg, int len) |
| { |
| while (len--) |
| { |
| ctx->Message_Block[ctx->Message_Block_Index++] = (*msg & 0xFF); |
| |
| ctx->Length_Low += 8; |
| if (ctx->Length_Low == 0) |
| { |
| ctx->Length_High++; |
| } |
| |
| if (ctx->Message_Block_Index == 64) |
| { |
| SHA1ProcessMessageBlock(ctx); |
| } |
| |
| msg++; |
| } |
| } |
| |
| /** |
| * Return the 160-bit message digest into the user's array |
| */ |
| void SHA1Final(SHA1_CTX *ctx, uint8_t *digest) |
| { |
| int i; |
| |
| SHA1PadMessage(ctx); |
| memset(ctx->Message_Block, 0, 64); |
| ctx->Length_Low = 0; /* and clear length */ |
| ctx->Length_High = 0; |
| |
| for (i = 0; i < SHA1_SIZE; i++) |
| { |
| digest[i] = ctx->Intermediate_Hash[i>>2] >> 8 * ( 3 - ( i & 0x03 ) ); |
| } |
| } |
| |
| /** |
| * Process the next 512 bits of the message stored in the array. |
| */ |
| static void SHA1ProcessMessageBlock(SHA1_CTX *ctx) |
| { |
| const uint32_t K[] = { /* Constants defined in SHA-1 */ |
| 0x5A827999, |
| 0x6ED9EBA1, |
| 0x8F1BBCDC, |
| 0xCA62C1D6 |
| }; |
| int t; /* Loop counter */ |
| uint32_t temp; /* Temporary word value */ |
| uint32_t W[80]; /* Word sequence */ |
| uint32_t A, B, C, D, E; /* Word buffers */ |
| |
| /* |
| * Initialize the first 16 words in the array W |
| */ |
| for (t = 0; t < 16; t++) |
| { |
| W[t] = ctx->Message_Block[t * 4] << 24; |
| W[t] |= ctx->Message_Block[t * 4 + 1] << 16; |
| W[t] |= ctx->Message_Block[t * 4 + 2] << 8; |
| W[t] |= ctx->Message_Block[t * 4 + 3]; |
| } |
| |
| for (t = 16; t < 80; t++) |
| { |
| W[t] = SHA1CircularShift(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]); |
| } |
| |
| A = ctx->Intermediate_Hash[0]; |
| B = ctx->Intermediate_Hash[1]; |
| C = ctx->Intermediate_Hash[2]; |
| D = ctx->Intermediate_Hash[3]; |
| E = ctx->Intermediate_Hash[4]; |
| |
| for (t = 0; t < 20; t++) |
| { |
| temp = SHA1CircularShift(5,A) + |
| ((B & C) | ((~B) & D)) + E + W[t] + K[0]; |
| E = D; |
| D = C; |
| C = SHA1CircularShift(30,B); |
| |
| B = A; |
| A = temp; |
| } |
| |
| for (t = 20; t < 40; t++) |
| { |
| temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[1]; |
| E = D; |
| D = C; |
| C = SHA1CircularShift(30,B); |
| B = A; |
| A = temp; |
| } |
| |
| for (t = 40; t < 60; t++) |
| { |
| temp = SHA1CircularShift(5,A) + |
| ((B & C) | (B & D) | (C & D)) + E + W[t] + K[2]; |
| E = D; |
| D = C; |
| C = SHA1CircularShift(30,B); |
| B = A; |
| A = temp; |
| } |
| |
| for (t = 60; t < 80; t++) |
| { |
| temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[3]; |
| E = D; |
| D = C; |
| C = SHA1CircularShift(30,B); |
| B = A; |
| A = temp; |
| } |
| |
| ctx->Intermediate_Hash[0] += A; |
| ctx->Intermediate_Hash[1] += B; |
| ctx->Intermediate_Hash[2] += C; |
| ctx->Intermediate_Hash[3] += D; |
| ctx->Intermediate_Hash[4] += E; |
| ctx->Message_Block_Index = 0; |
| } |
| |
| /* |
| * According to the standard, the message must be padded to an even |
| * 512 bits. The first padding bit must be a '1'. The last 64 |
| * bits represent the length of the original message. All bits in |
| * between should be 0. This function will pad the message |
| * according to those rules by filling the Message_Block array |
| * accordingly. It will also call the ProcessMessageBlock function |
| * provided appropriately. When it returns, it can be assumed that |
| * the message digest has been computed. |
| * |
| * @param ctx [in, out] The SHA1 context |
| */ |
| static void SHA1PadMessage(SHA1_CTX *ctx) |
| { |
| /* |
| * Check to see if the current message block is too small to hold |
| * the initial padding bits and length. If so, we will pad the |
| * block, process it, and then continue padding into a second |
| * block. |
| */ |
| if (ctx->Message_Block_Index > 55) |
| { |
| ctx->Message_Block[ctx->Message_Block_Index++] = 0x80; |
| while(ctx->Message_Block_Index < 64) |
| { |
| ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| } |
| |
| SHA1ProcessMessageBlock(ctx); |
| |
| while (ctx->Message_Block_Index < 56) |
| { |
| ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| } |
| } |
| else |
| { |
| ctx->Message_Block[ctx->Message_Block_Index++] = 0x80; |
| while(ctx->Message_Block_Index < 56) |
| { |
| |
| ctx->Message_Block[ctx->Message_Block_Index++] = 0; |
| } |
| } |
| |
| /* |
| * Store the message length as the last 8 octets |
| */ |
| ctx->Message_Block[56] = ctx->Length_High >> 24; |
| ctx->Message_Block[57] = ctx->Length_High >> 16; |
| ctx->Message_Block[58] = ctx->Length_High >> 8; |
| ctx->Message_Block[59] = ctx->Length_High; |
| ctx->Message_Block[60] = ctx->Length_Low >> 24; |
| ctx->Message_Block[61] = ctx->Length_Low >> 16; |
| ctx->Message_Block[62] = ctx->Length_Low >> 8; |
| ctx->Message_Block[63] = ctx->Length_Low; |
| SHA1ProcessMessageBlock(ctx); |
| } |