Separate lookup of LC_ENCRYPTION_INFO from usages.

[ldid.git] / sha1.c

/*\r
 *  sha1.c\r
 *\r
 *  Description:\r
 *      This file implements the Secure Hashing Algorithm 1 as\r
 *      defined in FIPS PUB 180-1 published April 17, 1995.\r
 *\r
 *      The SHA-1, produces a 160-bit message digest for a given\r
 *      data stream.  It should take about 2**n steps to find a\r
 *      message with the same digest as a given message and\r
 *      2**(n/2) to find any two messages with the same digest,\r
 *      when n is the digest size in bits.  Therefore, this\r
 *      algorithm can serve as a means of providing a\r
 *      "fingerprint" for a message.\r
 *\r
 *  Portability Issues:\r
 *      SHA-1 is defined in terms of 32-bit "words".  This code\r
 *      uses <stdint.h> (included via "sha1.h" to define 32 and 8\r
 *      bit unsigned integer types.  If your C compiler does not\r
 *      support 32 bit unsigned integers, this code is not\r
 *      appropriate.\r
 *\r
 *  Caveats:\r
 *      SHA-1 is designed to work with messages less than 2^64 bits\r
 *      long.  Although SHA-1 allows a message digest to be generated\r
 *      for messages of any number of bits less than 2^64, this\r
 *      implementation only works with messages with a length that is\r
 *      a multiple of the size of an 8-bit character.\r
 *\r
 */\r
\r
#include "sha1.h"\r
\r
/*\r
 *  Define the SHA1 circular left shift macro\r
 */\r
#define SHA1CircularShift(bits,word) \\r
                (((word) << (bits)) | ((word) >> (32-(bits))))\r
\r
/* Local Function Prototyptes */\r
void SHA1PadMessage(SHA1Context *);\r
void SHA1ProcessMessageBlock(SHA1Context *);\r
\r
/*\r
 *  SHA1Reset\r
 *\r
 *  Description:\r
 *      This function will initialize the SHA1Context in preparation\r
 *      for computing a new SHA1 message digest.\r
 *\r
 *  Parameters:\r
 *      context: [in/out]\r
 *          The context to reset.\r
 *\r
 *  Returns:\r
 *      sha Error Code.\r
 *\r
 */\r
int SHA1Reset(SHA1Context *context)\r
{\r
    if (!context)\r
    {\r
        return shaNull;\r
    }\r
\r
    context->Length_Low             = 0;\r
    context->Length_High            = 0;\r
    context->Message_Block_Index    = 0;\r
\r
    context->Intermediate_Hash[0]   = 0x67452301;\r
    context->Intermediate_Hash[1]   = 0xEFCDAB89;\r
    context->Intermediate_Hash[2]   = 0x98BADCFE;\r
    context->Intermediate_Hash[3]   = 0x10325476;\r
    context->Intermediate_Hash[4]   = 0xC3D2E1F0;\r
\r
    context->Computed   = 0;\r
    context->Corrupted  = 0;\r
\r
    return shaSuccess;\r
}\r
\r
/*\r
 *  SHA1Result\r
 *\r
 *  Description:\r
 *      This function will return the 160-bit message digest into the\r
 *      Message_Digest array  provided by the caller.\r
 *      NOTE: The first octet of hash is stored in the 0th element,\r
 *            the last octet of hash in the 19th element.\r
 *\r
 *  Parameters:\r
 *      context: [in/out]\r
 *          The context to use to calculate the SHA-1 hash.\r
 *      Message_Digest: [out]\r
 *          Where the digest is returned.\r
 *\r
 *  Returns:\r
 *      sha Error Code.\r
 *\r
 */\r
int SHA1Result( SHA1Context *context,\r
                uint8_t Message_Digest[SHA1HashSize])\r
{\r
    int i;\r
\r
    if (!context || !Message_Digest)\r
    {\r
        return shaNull;\r
    }\r
\r
    if (context->Corrupted)\r
    {\r
        return context->Corrupted;\r
    }\r
\r
    if (!context->Computed)\r
    {\r
        SHA1PadMessage(context);\r
        for(i=0; i<64; ++i)\r
        {\r
            /* message may be sensitive, clear it out */\r
            context->Message_Block[i] = 0;\r
        }\r
        context->Length_Low = 0;    /* and clear length */\r
        context->Length_High = 0;\r
        context->Computed = 1;\r
\r
    }\r
\r
    for(i = 0; i < SHA1HashSize; ++i)\r
    {\r
        Message_Digest[i] = context->Intermediate_Hash[i>>2]\r
                            >> 8 * ( 3 - ( i & 0x03 ) );\r
    }\r
\r
    return shaSuccess;\r
}\r
\r
/*\r
 *  SHA1Input\r
 *\r
 *  Description:\r
 *      This function accepts an array of octets as the next portion\r
 *      of the message.\r
 *\r
 *  Parameters:\r
 *      context: [in/out]\r
 *          The SHA context to update\r
 *      message_array: [in]\r
 *          An array of characters representing the next portion of\r
 *          the message.\r
 *      length: [in]\r
 *          The length of the message in message_array\r
 *\r
 *  Returns:\r
 *      sha Error Code.\r
 *\r
 */\r
int SHA1Input(    SHA1Context    *context,\r
                  const uint8_t  *message_array,\r
                  unsigned       length)\r
{\r
    if (!length)\r
    {\r
        return shaSuccess;\r
    }\r
\r
    if (!context || !message_array)\r
    {\r
        return shaNull;\r
    }\r
\r
    if (context->Computed)\r
    {\r
        context->Corrupted = shaStateError;\r
\r
        return shaStateError;\r
    }\r
\r
    if (context->Corrupted)\r
    {\r
         return context->Corrupted;\r
    }\r
    while(length-- && !context->Corrupted)\r
    {\r
    context->Message_Block[context->Message_Block_Index++] =\r
                    (*message_array & 0xFF);\r
\r
    context->Length_Low += 8;\r
    if (context->Length_Low == 0)\r
    {\r
        context->Length_High++;\r
        if (context->Length_High == 0)\r
        {\r
            /* Message is too long */\r
            context->Corrupted = 1;\r
        }\r
    }\r
\r
    if (context->Message_Block_Index == 64)\r
    {\r
        SHA1ProcessMessageBlock(context);\r
    }\r
\r
    message_array++;\r
    }\r
\r
    return shaSuccess;\r
}\r
\r
/*\r
 *  SHA1ProcessMessageBlock\r
 *\r
 *  Description:\r
 *      This function will process the next 512 bits of the message\r
 *      stored in the Message_Block array.\r
 *\r
 *  Parameters:\r
 *      None.\r
 *\r
 *  Returns:\r
 *      Nothing.\r
 *\r
 *  Comments:\r
\r
 *      Many of the variable names in this code, especially the\r
 *      single character names, were used because those were the\r
 *      names used in the publication.\r
 *\r
 *\r
 */\r
void SHA1ProcessMessageBlock(SHA1Context *context)\r
{\r
    const uint32_t K[] =    {       /* Constants defined in SHA-1   */\r
                            0x5A827999,\r
                            0x6ED9EBA1,\r
                            0x8F1BBCDC,\r
                            0xCA62C1D6\r
                            };\r
    int           t;                 /* Loop counter                */\r
    uint32_t      temp;              /* Temporary word value        */\r
    uint32_t      W[80];             /* Word sequence               */\r
    uint32_t      A, B, C, D, E;     /* Word buffers                */\r
\r
    /*\r
     *  Initialize the first 16 words in the array W\r
     */\r
    for(t = 0; t < 16; t++)\r
    {\r
        W[t] = context->Message_Block[t * 4] << 24;\r
        W[t] |= context->Message_Block[t * 4 + 1] << 16;\r
        W[t] |= context->Message_Block[t * 4 + 2] << 8;\r
        W[t] |= context->Message_Block[t * 4 + 3];\r
    }\r
\r
    for(t = 16; t < 80; t++)\r
    {\r
       W[t] = SHA1CircularShift(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]);\r
    }\r
\r
    A = context->Intermediate_Hash[0];\r
    B = context->Intermediate_Hash[1];\r
    C = context->Intermediate_Hash[2];\r
    D = context->Intermediate_Hash[3];\r
    E = context->Intermediate_Hash[4];\r
\r
    for(t = 0; t < 20; t++)\r
    {\r
        temp =  SHA1CircularShift(5,A) +\r
                ((B & C) | ((~B) & D)) + E + W[t] + K[0];\r
        E = D;\r
        D = C;\r
        C = SHA1CircularShift(30,B);\r
\r
        B = A;\r
        A = temp;\r
    }\r
\r
    for(t = 20; t < 40; t++)\r
    {\r
        temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[1];\r
        E = D;\r
        D = C;\r
        C = SHA1CircularShift(30,B);\r
        B = A;\r
        A = temp;\r
    }\r
\r
    for(t = 40; t < 60; t++)\r
    {\r
        temp = SHA1CircularShift(5,A) +\r
               ((B & C) | (B & D) | (C & D)) + E + W[t] + K[2];\r
        E = D;\r
        D = C;\r
        C = SHA1CircularShift(30,B);\r
        B = A;\r
        A = temp;\r
    }\r
\r
    for(t = 60; t < 80; t++)\r
    {\r
        temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[3];\r
        E = D;\r
        D = C;\r
        C = SHA1CircularShift(30,B);\r
        B = A;\r
        A = temp;\r
    }\r
\r
    context->Intermediate_Hash[0] += A;\r
    context->Intermediate_Hash[1] += B;\r
    context->Intermediate_Hash[2] += C;\r
    context->Intermediate_Hash[3] += D;\r
    context->Intermediate_Hash[4] += E;\r
\r
    context->Message_Block_Index = 0;\r
}\r
\r
/*\r
 *  SHA1PadMessage\r
 *\r
\r
 *  Description:\r
 *      According to the standard, the message must be padded to an even\r
 *      512 bits.  The first padding bit must be a '1'.  The last 64\r
 *      bits represent the length of the original message.  All bits in\r
 *      between should be 0.  This function will pad the message\r
 *      according to those rules by filling the Message_Block array\r
 *      accordingly.  It will also call the ProcessMessageBlock function\r
 *      provided appropriately.  When it returns, it can be assumed that\r
 *      the message digest has been computed.\r
 *\r
 *  Parameters:\r
 *      context: [in/out]\r
 *          The context to pad\r
 *      ProcessMessageBlock: [in]\r
 *          The appropriate SHA*ProcessMessageBlock function\r
 *  Returns:\r
 *      Nothing.\r
 *\r
 */\r
\r
void SHA1PadMessage(SHA1Context *context)\r
{\r
    /*\r
     *  Check to see if the current message block is too small to hold\r
     *  the initial padding bits and length.  If so, we will pad the\r
     *  block, process it, and then continue padding into a second\r
     *  block.\r
     */\r
    if (context->Message_Block_Index > 55)\r
    {\r
        context->Message_Block[context->Message_Block_Index++] = 0x80;\r
        while(context->Message_Block_Index < 64)\r
        {\r
            context->Message_Block[context->Message_Block_Index++] = 0;\r
        }\r
\r
        SHA1ProcessMessageBlock(context);\r
\r
        while(context->Message_Block_Index < 56)\r
        {\r
            context->Message_Block[context->Message_Block_Index++] = 0;\r
        }\r
    }\r
    else\r
    {\r
        context->Message_Block[context->Message_Block_Index++] = 0x80;\r
        while(context->Message_Block_Index < 56)\r
        {\r
\r
            context->Message_Block[context->Message_Block_Index++] = 0;\r
        }\r
    }\r
\r
    /*\r
     *  Store the message length as the last 8 octets\r
     */\r
    context->Message_Block[56] = context->Length_High >> 24;\r
    context->Message_Block[57] = context->Length_High >> 16;\r
    context->Message_Block[58] = context->Length_High >> 8;\r
    context->Message_Block[59] = context->Length_High;\r
    context->Message_Block[60] = context->Length_Low >> 24;\r
    context->Message_Block[61] = context->Length_Low >> 16;\r
    context->Message_Block[62] = context->Length_Low >> 8;\r
    context->Message_Block[63] = context->Length_Low;\r
\r
    SHA1ProcessMessageBlock(context);\r
}\r