//********************************************************************
//  Ver 1.0
//      2020.03.05   1、新建文件。
//********************************************************************
#include	"config.h"

SHA1_Str    SHA1_Info;

void    SHA1_Init(void)
{
    SHA1_Info.Sha1_h[0] = 0x67452301;
    SHA1_Info.Sha1_h[1] = 0xefcdab89;
    SHA1_Info.Sha1_h[2] = 0x98badcfe;
    SHA1_Info.Sha1_h[3] = 0x10325476;
    SHA1_Info.Sha1_h[4] = 0xc3d2e1f0;
}

void    SHA1_Byte2Word(INT8U *ptr, INT16U Len)
{
    INT16U i, j;

    for(i = 0; i < Len, i++)
    {
        SHA1_Info.Sha1_m[i] = 0;
        for(j = 0; j < 4; j++)
        {
            SHA1_Info.Sha1_m[i] = SHA1_Info.Sha1_m[i] << 8;
            SHA1_Info.Sha1_m[i] += ptr[i];
        }
    }
}

INT32U  SHA1_GetStrLen(INT8U *ptr)
{
    INT32U i = 0;

    while((ptr != NULL) && ((ptr[i]) != '\0'))
    {
        i++;
    }
    return(i);
}

void    SHA1_ClearM(void)
{
    MEM_Fill((INT8U *) & (SHA1_Info.Sha1_m), 0, sizeof(SHA1_Info.Sha1_m));
}

void    SHA1_ClearW(void)
{
    MEM_Fill((INT8U *) & (SHA1_Info.Sha1_w), 0, sizeof(SHA1_Info.Sha1_w));
}

void    SHA1_M2W(void)
{
    MEM_Copy((INT8U *) & (SHA1_Info.Sha1_m), (INT8U *) & (SHA1_Info.Sha1_w), sizeof(SHA1_Info.Sha1_m));
}

void    SHA1_AddLen2Word(INT32U Len)
{
    SHA1_Info.Sha1_m[14] = 0;
    SHA1_Info.Sha1_m[15] = Len * 8;
}

void    SHA1_ProChunk(void)
{
    INT32U sha1_A, sha1_B, sha1_C, sha1_D, sha1_E, sha1_T, sha1_V;
    INT32S i;

    SHA1_ClearW();
    SHA1_M2W();

    for(i = 16; i < SHA1_W_SIZE; i++)
    {
        sha1_V = SHA1_Info.Sha1_w[i - 3] ^ SHA1_Info.Sha1_w[i - 8] ^ SHA1_Info.Sha1_w[i - 14] ^ SHA1_Info.Sha1_w[i - 16];
        SHA1_Info.Sha1_w[i] = SHA1_SLeft(sha1_V, 1);
    }

    sha1_A = SHA1_Info.Sha1_h[0];
    sha1_B = SHA1_Info.Sha1_h[1];
    sha1_C = SHA1_Info.Sha1_h[2];
    sha1_D = SHA1_Info.Sha1_h[3];
    sha1_E = SHA1_Info.Sha1_h[4];

    for(i = 0; i < SHA1_W_SIZE; i++)
    {
        sha1_T = SHA1_SLeft(sha1_A, 5);
        sha1_T += sha1_E;
        sha1_T += SHA1_Info.Sha1_w[i];
        if((19 >= i) && (i >= 0))
        {
            sha1_T += (SHA1_Char(sha1_B, sha1_C, sha1_D) + SHA1_KT1);
        }
        if((39 >= i) && (i >= 20))
        {
            sha1_T += (SHA1_Parity(sha1_B, sha1_C, sha1_D) + SHA1_KT2);
        }
        if((59 >= i) && (i >= 40))
        {
            sha1_T += (SHA1_Maj(sha1_B, sha1_C, sha1_D) + SHA1_KT3);
        }
        if((79 >= i) && (i >= 60))
        {
            sha1_T += (SHA1_Parity(sha1_B, sha1_C, sha1_D) + SHA1_KT4);
        }
        sha1_E = sha1_D;
        sha1_D = sha1_C;
        sha1_C = SHA1_SLeft(sha1_B, 30);
        sha1_B = sha1_A;
        sha1_A = sha1_T;
    }
    SHA1_Info.Sha1_h[0] = sha1_A;
    SHA1_Info.Sha1_h[1] = sha1_B;
    SHA1_Info.Sha1_h[2] = sha1_C;
    SHA1_Info.Sha1_h[3] = sha1_D;
    SHA1_Info.Sha1_h[4] = sha1_E;
}

//因为是非标版，所以输入必须为8字节的倍数
//本程序中待处理的字符串长度不得大于2^16 bit
void    SHA1_Process(INT8U *ptr)
{
    INT32U Len[2];
    INT8U *ptr_t;
    INT8U i, j;

    Len[0] = SHA1_GetStrLen(ptr); //获取数据长度
    Len[1] = Len[0];
    ptr_t = ptr;

    SHA1_Init();
    while((Len[0] / 64) > 0)
    {
        SHA1_Byte2Word(ptr_t, 16);
        SHA1_ProChunk();
        SHA1_ClearM();
        Len[0] -= 64;
        ptr_t += 64;
    }
    SHA1_Byte2Word(ptr_t, Len[0] / 4);
    i = Len[0] % 4;
    j = Len[0] / 4;
    SHA1_Info.Sha1_m[j] = 0;
    switch(Len[0] % 4)
    {
    case 0:
        SHA1_Info.Sha1_m[j] |= 0x80000000;
        break;

    case 1:
        SHA1_Info.Sha1_m[j] = *ptr_t;
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 24;
        SHA1_Info.Sha1_m[j] |= 0x00800000;
        break;

    case 2:
        SHA1_Info.Sha1_m[j] = *ptr_t;
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 8;
        SHA1_Info.Sha1_m[j] += *(ptr_t + 1);
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 16;
        SHA1_Info.Sha1_m[j] |= 0x00008000;
        break;

    case 3:
        SHA1_Info.Sha1_m[j] = *ptr_t;
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 8;
        SHA1_Info.Sha1_m[j] += *(ptr_t + 1);
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 8;
        SHA1_Info.Sha1_m[j] += *(ptr_t + 2);
        SHA1_Info.Sha1_m[j] = SHA1_Info.Sha1_m[j] << 8;
        SHA1_Info.Sha1_m[j] |= 0x00000080;
        break;
    }

    if((64 > Len[0]) && (Len[0] >= 56))
    {
        SHA1_ProChunk();
        SHA1_ClearM();
    }
    SHA1_AddLen2Word(Len[1]);
    SHA1_ProChunk();
}