#include "stdafx.h"
#include <stdio.h>
#include "user_identification.h"

typedef struct SHA1Context
{
    unsigned Message_Digest[5]; /* Message Digest (output)          */

    unsigned Length_Low;        /* Message length in bits           */
    unsigned Length_High;       /* Message length in bits           */

    unsigned char Message_Block[64]; /* 512-bit message blocks      */
    int Message_Block_Index;    /* Index into message block array   */

    int Computed;               /* Is the digest computed?          */
    int Corrupted;              /* Is the message digest corruped?  */
} SHA1Context;

#define SHA_DIGEST_LENGTH 20

void SHA1Reset(SHA1Context *);
int SHA1Result(SHA1Context *);
void SHA1Input( SHA1Context *,
                const unsigned char *,
                unsigned);


#define SHA1CircularShift(bits,word) \
                ((((word) << (bits)) & 0xFFFFFFFF) | \
                ((word) >> (32-(bits))))

/* Function prototypes */
void SHA1ProcessMessageBlock(SHA1Context *);
void SHA1PadMessage(SHA1Context *);

void SHA1Reset(SHA1Context *context)
{
    context->Length_Low             = 0;
    context->Length_High            = 0;
    context->Message_Block_Index    = 0;

    context->Message_Digest[0]      = 0x67452301;
    context->Message_Digest[1]      = 0xEFCDAB89;
    context->Message_Digest[2]      = 0x98BADCFE;
    context->Message_Digest[3]      = 0x10325476;
    context->Message_Digest[4]      = 0xC3D2E1F0;

    context->Computed   = 0;
    context->Corrupted  = 0;
}

int SHA1Result(SHA1Context *context)
{

    if (context->Corrupted)
    {
        return 0;
    }

    if (!context->Computed)
    {
        SHA1PadMessage(context);
        context->Computed = 1;
    }

    return 1;
}

void SHA1Input(     SHA1Context         *context,
                    const unsigned char *message_array,
                    unsigned            length)
{
    if (!length)
    {
        return;
    }

    if (context->Computed || context->Corrupted)
    {
        context->Corrupted = 1;
        return;
    }

    while(length-- && !context->Corrupted)
    {
        context->Message_Block[context->Message_Block_Index++] =
                                                (*message_array & 0xFF);

        context->Length_Low += 8;
        /* Force it to 32 bits */
        context->Length_Low &= 0xFFFFFFFF;
        if (context->Length_Low == 0)
        {
            context->Length_High++;
            /* Force it to 32 bits */
            context->Length_High &= 0xFFFFFFFF;
            if (context->Length_High == 0)
            {
                /* Message is too long */
                context->Corrupted = 1;
            }
        }

        if (context->Message_Block_Index == 64)
        {
            SHA1ProcessMessageBlock(context);
        }

        message_array++;
    }
}

void SHA1ProcessMessageBlock(SHA1Context *context)
{
    const unsigned K[] =            /* Constants defined in SHA-1   */      
    {
        0x5A827999,
        0x6ED9EBA1,
        0x8F1BBCDC,
        0xCA62C1D6
    };
    int         t;                  /* Loop counter                 */
    unsigned    temp;               /* Temporary word value         */
    unsigned    W[80];              /* Word sequence                */
    unsigned    A, B, C, D, E;      /* Word buffers                 */

    /*
     *  Initialize the first 16 words in the array W
     */
    for(t = 0; t < 16; t++)
    {
        W[t] = ((unsigned) context->Message_Block[t * 4]) << 24;
        W[t] |= ((unsigned) context->Message_Block[t * 4 + 1]) << 16;
        W[t] |= ((unsigned) context->Message_Block[t * 4 + 2]) << 8;
        W[t] |= ((unsigned) 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->Message_Digest[0];
    B = context->Message_Digest[1];
    C = context->Message_Digest[2];
    D = context->Message_Digest[3];
    E = context->Message_Digest[4];

    for(t = 0; t < 20; t++)
    {
        temp =  SHA1CircularShift(5,A) +
                ((B & C) | ((~B) & D)) + E + W[t] + K[0];
        temp &= 0xFFFFFFFF;
        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];
        temp &= 0xFFFFFFFF;
        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];
        temp &= 0xFFFFFFFF;
        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];
        temp &= 0xFFFFFFFF;
        E = D;
        D = C;
        C = SHA1CircularShift(30,B);
        B = A;
        A = temp;
    }

    context->Message_Digest[0] =
                        (context->Message_Digest[0] + A) & 0xFFFFFFFF;
    context->Message_Digest[1] =
                        (context->Message_Digest[1] + B) & 0xFFFFFFFF;
    context->Message_Digest[2] =
                        (context->Message_Digest[2] + C) & 0xFFFFFFFF;
    context->Message_Digest[3] =
                        (context->Message_Digest[3] + D) & 0xFFFFFFFF;
    context->Message_Digest[4] =
                        (context->Message_Digest[4] + E) & 0xFFFFFFFF;

    context->Message_Block_Index = 0;
}

void SHA1PadMessage(SHA1Context *context)
{
    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;
        }
    }

    context->Message_Block[56] = (context->Length_High >> 24) & 0xFF;
    context->Message_Block[57] = (context->Length_High >> 16) & 0xFF;
    context->Message_Block[58] = (context->Length_High >> 8) & 0xFF;
    context->Message_Block[59] = (context->Length_High) & 0xFF;
    context->Message_Block[60] = (context->Length_Low >> 24) & 0xFF;
    context->Message_Block[61] = (context->Length_Low >> 16) & 0xFF;
    context->Message_Block[62] = (context->Length_Low >> 8) & 0xFF;
    context->Message_Block[63] = (context->Length_Low) & 0xFF;

    SHA1ProcessMessageBlock(context);
}


WCHAR *GetUserHash(WCHAR *user_sid)
{
	char ascii_sid[256];
	WCHAR *output;
	SHA1Context sha;

	if ( !(output = (WCHAR *)calloc((SHA_DIGEST_LENGTH*2)+1, sizeof(WCHAR)) ) )
		return NULL;

	sprintf_s(ascii_sid, sizeof(ascii_sid), "%S", user_sid);
	SHA1Reset(&sha);
	SHA1Input(&sha, (const unsigned char *)ascii_sid, (DWORD)(strlen(ascii_sid)));
	if (SHA1Result(&sha)) {
		for (int i=0; i<(SHA_DIGEST_LENGTH/sizeof(int)); i++) 
			swprintf_s(output+(i*8), (SHA_DIGEST_LENGTH*2)+1-(i*8), L"%.8X", sha.Message_Digest[i]);
	} else 
		swprintf_s(output, SHA_DIGEST_LENGTH, L"UNKNOWN");
	return output;
}
.