/* * To change this template, choose Tools | Templates * and open the template in the editor. */package sha1lab;/* * To change this template, choose Tools | Templates * and open the template in the editor. *//** * * @author Fredrik */public class SHA1 {        //internal hash values    private int[] H;    //the padded message as 32-bit words    private int[] M32;    //the message used in the rounds    private int[] W;    //the round constants    private int[] K;    public SHA1(){        W=new int[80];        H=new int[5];        K=new int[80];        for(int i=0;i<20;i++)            K[i]=0x5a827999;        for(int i=20;i<40;i++)            K[i]=0x6ed9eba1;        for(int i=40;i<60;i++)            K[i]=0x8f1bbcdc;        for(int i=60;i<80;i++)            K[i]=0xca62c1d6;    }        public byte[] hash(byte[] message){        //calculates the hash of the message        byte[] hashValue=new byte[20];        //pad the message               //initiate internal hash value                //calculate the number of 512-bit block for the padded message                int a,b,c,d,e,T;        //repeat for each 512-bit block in M                    //initW                        //init a,b,c,d,e                                   //run 80 iterations of the round function                                   //update H                       //use H to form hashvalue        for(int i=0;i<20;i++)           hashValue[i]=0;        return hashValue;    }        private void initM(byte[] message){        //pad the message and write it to W        int messageLength8=message.length; //the number of bytes in the message        //calculates the number of bytes to pad        int padLength=(64-((messageLength8+8)%64));        int totalLength8=messageLength8+padLength+8;        byte[] temp= new byte[totalLength8];        //pad the message and store in temp        for(int i=0;i<message.length;i++)            temp[i]=message[i];        temp[message.length]=(byte)0x80;        for(int i=message.length+1;i<totalLength8;i++)            temp[i]=0;        //write the length        long bitLength=message.length*8;        for(int i=1;i<=8;i++){            temp[totalLength8-i]=(byte)(bitLength&0xff);            bitLength>>=8;        }               //copy temp to M32        int totalLength32=totalLength8/4;        M32=new int[totalLength32];        for(int i=0;i<totalLength32;i++){            M32[i]=0;            //copy four bytes and write to 32 bit integer            for(int j=0;j<4;j++){                M32[i]<<=8;                M32[i]|=((int)temp[4*i+j]&0xff);            }        }    }        private void initH(){        H[0]=0x67452301;        H[1]=0xefcdab89;        H[2]=0x98badcfe;        H[3]=0x10325476;        H[4]=0xc3d2e1f0;    }        private int ROTL(int x,int n){        int temp=((x>>>(32-n))|(x<<n));        //System.out.printf("ROTL %d\t%08x\t%08x\t%08x\t%08x\n",n,x,(x>>>n),(x<<n),temp);        return temp;    }        private void initW(int n){        for(int i=0;i<16;i++)            W[i]=M32[n*16+i];        for(int i=16;i<80;i++){            int temp=W[i-3]^W[i-8]^W[i-14]^W[i-16];            W[i]=ROTL(temp,1);        }    }        private int ft(int x,int y,int z,int t){        if(t<20)            return ((x&y)^(~x&z));        if(t<40)            return (x^y^z);        if(t<60)            return ((x&y)^(x&z)^(y&z));        return (x^y^z);    }}