| /* |
| * Copyright (C) The Internet Society (2001). All Rights Reserved. |
| * |
| * This document and translations of it may be copied and furnished to |
| * others, and derivative works that comment on or otherwise explain it |
| * or assist in its implementation may be prepared, copied, published |
| * and distributed, in whole or in part, without restriction of any |
| * kind, provided that the above copyright notice and this paragraph are |
| * included on all such copies and derivative works. However, this |
| * document itself may not be modified in any way, such as by removing |
| * the copyright notice or references to the Internet Society or other |
| * Internet organizations, except as needed for the purpose of |
| * developing Internet standards in which case the procedures for |
| * copyrights defined in the Internet Standards process must be |
| * followed, or as required to translate it into languages other than |
| * English. |
| * |
| * The limited permissions granted above are perpetual and will not be |
| * revoked by the Internet Society or its successors or assigns. |
| * |
| * This document and the information contained herein is provided on an |
| * "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING |
| * TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING |
| * BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION |
| * HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF |
| * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. |
| */ |
| |
| /* |
| * sha1.c |
| * |
| * Description: |
| * This file implements the Secure Hashing Algorithm 1 as |
| * defined in FIPS PUB 180-1 published April 17, 1995. |
| * |
| * The SHA-1, produces a 160-bit message digest for a given |
| * data stream. It should take about 2**n steps to find a |
| * message with the same digest as a given message and |
| * 2**(n/2) to find any two messages with the same digest, |
| * when n is the digest size in bits. Therefore, this |
| * algorithm can serve as a means of providing a |
| * "fingerprint" for a message. |
| * |
| * Portability Issues: |
| * SHA-1 is defined in terms of 32-bit "words". This code |
| * uses <stdint.h> (included via "sha1.h" to define 32 and 8 |
| * bit unsigned integer types. If your C compiler does not |
| * support 32 bit unsigned integers, this code is not |
| * appropriate. |
| * |
| * Caveats: |
| * SHA-1 is designed to work with messages less than 2^64 bits |
| * long. Although SHA-1 allows a message digest to be generated |
| * for messages of any number of bits less than 2^64, this |
| * implementation only works with messages with a length that is |
| * a multiple of the size of an 8-bit character. |
| * |
| */ |
| |
| #include "sha1.h" |
| |
| /* |
| * Define the SHA1 circular left shift macro |
| */ |
| #define SHA1CircularShift(bits,word) \ |
| (((word) << (bits)) | ((word) >> (32-(bits)))) |
| |
| /* Local Function Prototyptes */ |
| void SHA1PadMessage(SHA1Context *); |
| void SHA1ProcessMessageBlock(SHA1Context *); |
| |
| /* |
| * SHA1Reset |
| * |
| * Description: |
| * This function will initialize the SHA1Context in preparation |
| * for computing a new SHA1 message digest. |
| * |
| * Parameters: |
| * context: [in/out] |
| * The context to reset. |
| * |
| * Returns: |
| * sha Error Code. |
| * |
| */ |
| int SHA1Reset(SHA1Context *context) |
| { |
| if (!context) |
| { |
| return shaNull; |
| } |
| |
| context->Length_Low = 0; |
| context->Length_High = 0; |
| context->Message_Block_Index = 0; |
| |
| context->Intermediate_Hash[0] = 0x67452301; |
| context->Intermediate_Hash[1] = 0xEFCDAB89; |
| context->Intermediate_Hash[2] = 0x98BADCFE; |
| context->Intermediate_Hash[3] = 0x10325476; |
| context->Intermediate_Hash[4] = 0xC3D2E1F0; |
| |
| context->Computed = 0; |
| context->Corrupted = 0; |
| return shaSuccess; |
| } |
| |
| /* |
| * SHA1Result |
| * |
| * Description: |
| * This function will return the 160-bit message digest into the |
| * Message_Digest array provided by the caller. |
| * NOTE: The first octet of hash is stored in the 0th element, |
| * the last octet of hash in the 19th element. |
| * |
| * Parameters: |
| * context: [in/out] |
| * The context to use to calculate the SHA-1 hash. |
| * Message_Digest: [out] |
| * Where the digest is returned. |
| * |
| * Returns: |
| * sha Error Code. |
| * |
| */ |
| int SHA1Result( SHA1Context *context, |
| uint8_t Message_Digest[SHA1HashSize]) |
| { |
| int i; |
| |
| if (!context || !Message_Digest) |
| { |
| return shaNull; |
| } |
| |
| if (context->Corrupted) |
| { |
| return context->Corrupted; |
| } |
| |
| if (!context->Computed) |
| { |
| SHA1PadMessage(context); |
| for(i=0; i<64; ++i) |
| { |
| /* message may be sensitive, clear it out */ |
| context->Message_Block[i] = 0; |
| } |
| context->Length_Low = 0; /* and clear length */ |
| context->Length_High = 0; |
| context->Computed = 1; |
| } |
| |
| for(i = 0; i < SHA1HashSize; ++i) |
| { |
| Message_Digest[i] = context->Intermediate_Hash[i>>2] |
| >> 8 * ( 3 - ( i & 0x03 ) ); |
| } |
| |
| return shaSuccess; |
| } |
| |
| /* |
| * SHA1Input |
| * |
| * Description: |
| * This function accepts an array of octets as the next portion |
| * of the message. |
| * |
| * Parameters: |
| * context: [in/out] |
| * The SHA context to update |
| * message_array: [in] |
| * An array of characters representing the next portion of |
| * the message. |
| * length: [in] |
| * The length of the message in message_array |
| * |
| * Returns: |
| * sha Error Code. |
| * |
| */ |
| int SHA1Input( SHA1Context *context, |
| const uint8_t *message_array, |
| unsigned length) |
| { |
| if (!length) |
| { |
| return shaSuccess; |
| } |
| |
| if (!context || !message_array) |
| { |
| return shaNull; |
| } |
| |
| if (context->Computed) |
| { |
| context->Corrupted = shaStateError; |
| return shaStateError; |
| } |
| |
| if (context->Corrupted) |
| { |
| return context->Corrupted; |
| } |
| while(length-- && !context->Corrupted) |
| { |
| context->Message_Block[context->Message_Block_Index++] = |
| (*message_array & 0xFF); |
| |
| context->Length_Low += 8; |
| if (context->Length_Low == 0) |
| { |
| context->Length_High++; |
| if (context->Length_High == 0) |
| { |
| /* Message is too long */ |
| context->Corrupted = 1; |
| } |
| } |
| |
| if (context->Message_Block_Index == 64) |
| { |
| SHA1ProcessMessageBlock(context); |
| } |
| |
| message_array++; |
| } |
| |
| return shaSuccess; |
| } |
| |
| /* |
| * SHA1ProcessMessageBlock |
| * |
| * Description: |
| * This function will process the next 512 bits of the message |
| * stored in the Message_Block array. |
| * |
| * Parameters: |
| * None. |
| * |
| * Returns: |
| * Nothing. |
| * |
| * Comments: |
| * Many of the variable names in this code, especially the |
| * single character names, were used because those were the |
| * names used in the publication. |
| * |
| * |
| */ |
| void SHA1ProcessMessageBlock(SHA1Context *context) |
| { |
| 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] = context->Message_Block[t * 4] << 24; |
| W[t] |= context->Message_Block[t * 4 + 1] << 16; |
| W[t] |= context->Message_Block[t * 4 + 2] << 8; |
| W[t] |= context->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 = context->Intermediate_Hash[0]; |
| B = context->Intermediate_Hash[1]; |
| C = context->Intermediate_Hash[2]; |
| D = context->Intermediate_Hash[3]; |
| E = context->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; |
| } |
| |
| context->Intermediate_Hash[0] += A; |
| context->Intermediate_Hash[1] += B; |
| context->Intermediate_Hash[2] += C; |
| context->Intermediate_Hash[3] += D; |
| context->Intermediate_Hash[4] += E; |
| |
| context->Message_Block_Index = 0; |
| } |
| |
| |
| /* |
| * SHA1PadMessage |
| * |
| * Description: |
| * 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. |
| * |
| * Parameters: |
| * context: [in/out] |
| * The context to pad |
| * ProcessMessageBlock: [in] |
| * The appropriate SHA*ProcessMessageBlock function |
| * Returns: |
| * Nothing. |
| * |
| */ |
| |
| void SHA1PadMessage(SHA1Context *context) |
| { |
| /* |
| * 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 (context->Message_Block_Index > 55) |
| { |
| context->Message_Block[context->Message_Block_Index++] = 0x80; |
| while(context->Message_Block_Index < 64) |
| { |
| context->Message_Block[context->Message_Block_Index++] = 0; |
| } |
| |
| SHA1ProcessMessageBlock(context); |
| |
| while(context->Message_Block_Index < 56) |
| { |
| context->Message_Block[context->Message_Block_Index++] = 0; |
| } |
| } |
| else |
| { |
| context->Message_Block[context->Message_Block_Index++] = 0x80; |
| while(context->Message_Block_Index < 56) |
| { |
| context->Message_Block[context->Message_Block_Index++] = 0; |
| } |
| } |
| |
| /* |
| * Store the message length as the last 8 octets |
| */ |
| context->Message_Block[56] = context->Length_High >> 24; |
| context->Message_Block[57] = context->Length_High >> 16; |
| context->Message_Block[58] = context->Length_High >> 8; |
| context->Message_Block[59] = context->Length_High; |
| context->Message_Block[60] = context->Length_Low >> 24; |
| context->Message_Block[61] = context->Length_Low >> 16; |
| context->Message_Block[62] = context->Length_Low >> 8; |
| context->Message_Block[63] = context->Length_Low; |
| |
| SHA1ProcessMessageBlock(context); |
| } |