PAC

#include <stdio.h>

static unsigned int PAC_fun(unsigned long long * point,int mode){
    unsigned long long key = 0x4655434b434f4445;
    unsigned long long tmphash=0;
    unsigned long long finhash=0;
    switch (mode)
    {
    case 0://32 bit-HASH
        tmphash = ((key ^ *point));
        *point += (tmphash&0xFF+(tmphash>>8)&0xFF+(tmphash>>16)&0xFF)<<24;
        printf("Hash32 : %x \n",tmphash);
        return 1;
    case 1://64 bit-HASH
        tmphash = ((key ^ *point));
        *point += (tmphash&0xFF+(tmphash>>8)&0xFF+(tmphash>>16)&0xFF+(tmphash>>16)&0xFF00+(tmphash>>24)&0xFF00+(tmphash<<32)&0xFF00)<<56;
        printf("Hash64 : %x \n",tmphash);
        return 1;
    case 2://32 bit-Verify
        tmphash = ((*point)>>24)&0xff;
        *point = *point & 0xffffff;
        finhash = ((key ^ *point));
        finhash = (finhash&0xFF+(finhash>>8)&0xFF+(finhash>>16)&0xFF)<<24;
        if (tmphash == finhash){
            return 1;
        }else
        {
            return 0;
        }
    case 3://64 bit-Verify
        tmphash = ((*point)>>48)&0xffffff;
        *point = *point & 0xffffffffffff;
        finhash = ((key ^ *point));
        finhash = (finhash&0xFF+(finhash>>8)&0xFF+(finhash>>16)&0xFF+(finhash>>16)&0xFF00+(finhash>>24)&0xFF00+(finhash<<32)&0xFF00)<<56;
        if (tmphash == finhash){
            return 1;
        }else
        {
            return 0;
        }
    default:
        break;
    }
    return 0;
}


void main(){
    long long point = 0x3312334989;
    unsigned int ret =0;
    ret = PAC_fun(&point,1);
    printf("This point After is 0x%x \n",point);
    ret = PAC_fun(&point,3);
    printf("This check si %d ,point =%x \n",ret,point);
    return;
}