//********************************************************************
//  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();
}