Topic: GPU ile Eliptik Eğri Aritmetiği ve Programlama Hakkında (Read 337 times)

# -*- coding: utf-8 -*-
"""
Created on Wed Dec 23 09:43:04 2020

"""

import gmpy2

modulo = 2**256 - 2**32 - 2**9 - 2**8 - 2**7 - 2**6 - 2**4 -1
order  = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
Gx = 55066263022277343669578718895168534326250603453777594175500187360389116729240
Gy = 32670510020758816978083085130507043184471273380659243275938904335757337482424

class Point:
    def __init__(self, x=0, y=0):
        self.x = x
        self.y = y


Z = Point(0,0) # zero-point, infinite in real x,y - plane

# return (g, x, y) a*x + b*y = gcd(x, y)
def egcd(a, b):
    if a == 0:
        return (b, 0, 1)
    else:
        g, x, y = egcd(b % a, a)
        return (g, y - (b // a) * x, x)

def modinv(m, n = modulo):
    while m < 0:
        m += n
    g, x, _ = egcd(m, n)
    if g == 1:
        return x % n

    else: print (' no inverse exist')

def mul2(Pmul2, p = modulo):
    R = Point(0,0)
    #c = 3*Pmul2.x*Pmul2.x*modinv(2*Pmul2.y, p) % p
    c = 3*Pmul2.x*Pmul2.x*gmpy2.invert(2*Pmul2.y, p) % p
    R.x = (c*c-2*Pmul2.x) % p
    R.y = (c*(Pmul2.x - R.x)-Pmul2.y) % p
    return R

def add(Padd, Q, p = modulo):
    if Padd.x == Padd.y == 0: return Q
    if Q.x == Q.y == 0: return Padd
    if Padd == Q: return mul2(Q)
    R = Point()
    dx = (Q.x - Padd.x) % p
    dy = (Q.y - Padd.y) % p
    c = dy * gmpy2.invert(dx, p) % p    
    #c = dy * modinv(dx, p) % p
    R.x = (c*c - Padd.x - Q.x) % p
    R.y = (c*(Padd.x - R.x) - Padd.y) % p
    return R # 6 sub, 3 mul, 1 inv

def mulk(k, Pmulk, p = modulo):
    if k == 0: return Z
    if k == 1: return Pmulk
    if (k % 2 == 0): return mulk(k//2, mul2(Pmulk, p), p)
    return add(Pmulk, mulk((k-1)//2, mul2(Pmulk, p), p), p)



x = 8723493475893459873498759834758934759837458973497593847598347598734985798982374987234 % order

G = Point(Gx,Gy)

GeneratorPoint = G
PrivateKey = x

print ('PrivateKey -> ' + str(PrivateKey))
print ('\n')

#PublicPoint = PrivateKey * GeneratorPoint
PublicPoint = mulk (PrivateKey , GeneratorPoint, order )

print ('PublicPoint.x -> ' + str(PublicPoint.x))
print ('PublicPoint.y -> ' + str(PublicPoint.y))
print ('\n')

xx = hex(PublicPoint.x)
xy = hex(PublicPoint.y)

print ('hex(PrivateKey.x) -> ' + str(hex(PublicPoint.x)))
print ('hex(PrivateKey.y) -> ' + str(hex(PublicPoint.y)))
print ('\n')

xx = xx.lstrip('0x')
xy = xy.lstrip('0x')

print ("xx.lstrip('0x') -> " + xx)
print ("xy.lstrip('0x') -> " + xy)
print ('\n')


UnComporessedPublicKey = str('04') + xx + xy

print ("UnComporessedPublicKey -> " + UnComporessedPublicKey)
print ('\n')


if PublicPoint.y %2 == 0 :
    ComporessedPublicKey = str('02') + xx
    
if PublicPoint.y %2 == 1 :
    ComporessedPublicKey = str('03') + xx
    
print ('ComporessedPublicKey-> ' +  ComporessedPublicKey)
print ('\n')


print ('Publicpoint ->',PublicPoint)

PrivateKey -> 5451796761803755337407808980699837804368931494179568164251072816313071589514


PublicPoint.x -> 88592974801524563600300001436396082991077345600545970471017048342658174170961
PublicPoint.y -> 107521544534117035401926583528158785822472831725006965096095309778371330834318


hex(PrivateKey.x) -> 0xc3ddd8c66a446ac611140bdf0681877fc07849a5ffacff64d9bc9d3cdffc3751
hex(PrivateKey.y) -> 0xedb7099f2c70008aee7c51984c185b4997e033c55e9893d5d4c73832c561ff8e


xx.lstrip('0x') -> c3ddd8c66a446ac611140bdf0681877fc07849a5ffacff64d9bc9d3cdffc3751
xy.lstrip('0x') -> edb7099f2c70008aee7c51984c185b4997e033c55e9893d5d4c73832c561ff8e


UnComporessedPublicKey -> 04c3ddd8c66a446ac611140bdf0681877fc07849a5ffacff64d9bc9d3cdffc3751edb7099f2c70008aee7c51984c185b4997e033c55e9893d5d4c73832c561ff8e


ComporessedPublicKey-> 02c3ddd8c66a446ac611140bdf0681877fc07849a5ffacff64d9bc9d3cdffc3751


Publicpoint -> <__main__.Point object at 0x0000016B1D4E1610>

static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            BigInteger p = BigInteger.Parse("0FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F", NumberStyles.HexNumber);
            BigInteger a = BigInteger.Zero;
            BigInteger b = (BigInteger)7;


            var secp256k1 = new CurveFp(p, a, b);

            var G = new Point(secp256k1,
                BigInteger.Parse("55066263022277343669578718895168534326250603453777594175500187360389116729240"),
                BigInteger.Parse("32670510020758816978083085130507043184471273380659243275938904335757337482424"));

            var x = BigInteger.Parse("8723493475893459873498759834758934759837458973497593847598347598734985798982374987234");

            var PrivateKey = x;
            var GeneratorPoint = G;

            var PublicPoint = GeneratorPoint * PrivateKey;

            var xx = PublicPoint.X.ToString("X");

            var xy = PublicPoint.Y.ToString("X");

            var UncompressedPublicKey = "04" + xx + xy;

            var CompressedPublicKey = "";

            if (PublicPoint.Y % 2 == 0)
                CompressedPublicKey = "02" + xx;

            if (PublicPoint.Y % 2 == 1)
                CompressedPublicKey = "03" + xx;

            Console.WriteLine("Uncompressed Public Key: {0}", UncompressedPublicKey);
            Console.WriteLine("Compressed Public Key: {0}", CompressedPublicKey);

            Console.ReadLine();
        }

static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            // TODO: generate private key and public key

            // Örnek CurveFp ve Point nasıl kullanılır?

            var curve = new CurveFp(5, 2, 3);

            var point = new Point(curve, 19, 23);

            var point2 = new Point(curve, 17, 11);

            var sampleAdd = point + point2;

            var skaler = 31;

            var sampleMultiple = point * skaler;

            var doublePoint = point.Double();

            Console.WriteLine("Sample Add: {0}", sampleAdd);
            Console.WriteLine("Sample Multiple: {0}", sampleMultiple);
            Console.WriteLine("Sample Double: {0}", doublePoint);

            Console.ReadLine();
        }

using System;
using System.Text;
using System.Numerics;

namespace TestEllipticCurve
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            // TODO: generate private key and public key

            // Örnek CurveFp ve Point nasıl kullanılır?

            var curve = new CurveFp(5, 2, 3);

            var point = new Point(curve, 19, 23);

            var point2 = new Point(curve, 17, 11);

            var sampleAdd = point + point2;

            var skaler = 31;

            var sampleMultiple = point * skaler;

            Console.WriteLine("Sample Add: {0}", sampleAdd);
            Console.WriteLine("Sample Multiple: {0}", sampleMultiple);

            Console.ReadLine();
        }

        class Point
        {
            public static readonly Point INFINITY = new Point(null, default(BigInteger), default(BigInteger));
            public CurveFp Curve { get; private set; }
            public BigInteger X { get; private set; }
            public BigInteger Y { get; private set; }

            public Point(CurveFp curve, BigInteger x, BigInteger y)
            {
                this.Curve = curve;
                this.X = x;
                this.Y = y;
            }
            public Point Double()
            {
                if (this == INFINITY)
                    return INFINITY;

                BigInteger p = this.Curve.p;
                BigInteger a = this.Curve.a;
                BigInteger l = ((3 * this.X * this.X + a) * InverseMod(2 * this.Y, p)) % p;
                BigInteger x3 = (l * l - 2 * this.X) % p;
                BigInteger y3 = (l * (this.X - x3) - this.Y) % p;
                return new Point(this.Curve, x3, y3);
            }
            public override string ToString()
            {
                if (this == INFINITY)
                    return "infinity";
                return string.Format("({0},{1})", this.X, this.Y);
            }
            public static Point operator +(Point left, Point right)
            {
                if (right == INFINITY)
                    return left;
                if (left == INFINITY)
                    return right;
                if (left.X == right.X)
                {
                    if ((left.Y + right.Y) % left.Curve.p == 0)
                        return INFINITY;
                    else
                        return left.Double();
                }

                var p = left.Curve.p;
                var l = ((right.Y - left.Y) * InverseMod(right.X - left.X, p)) % p;
                var x3 = (l * l - left.X - right.X) % p;
                var y3 = (l * (left.X - x3) - left.Y) % p;
                return new Point(left.Curve, x3, y3);
            }
            public static Point operator *(Point left, BigInteger right)
            {
                var e = right;
                if (e == 0 || left == INFINITY)
                    return INFINITY;
                var e3 = 3 * e;
                var negativeLeft = new Point(left.Curve, left.X, -left.Y);
                var i = LeftmostBit(e3) / 2;
                var result = left;
                while (i > 1)
                {
                    result = result.Double();
                    if ((e3 & i) != 0 && (e & i) == 0)
                        result += left;
                    if ((e3 & i) == 0 && (e & i) != 0)
                        result += negativeLeft;
                    i /= 2;
                }
                return result;
            }

            private static BigInteger LeftmostBit(BigInteger x)
            {
                BigInteger result = 1;
                while (result <= x)
                    result = 2 * result;
                return result / 2;
            }
            private static BigInteger InverseMod(BigInteger a, BigInteger m)
            {
                while (a < 0) a += m;
                if (a < 0 || m <= a)
                    a = a % m;
                BigInteger c = a;
                BigInteger d = m;

                BigInteger uc = 1;
                BigInteger vc = 0;
                BigInteger ud = 0;
                BigInteger vd = 1;

                while (c != 0)
                {
                    BigInteger r;
                    //q, c, d = divmod( d, c ) + ( c, );
                    var q = BigInteger.DivRem(d, c, out r);
                    d = c;
                    c = r;

                    //uc, vc, ud, vd = ud - q*uc, vd - q*vc, uc, vc;
                    var uct = uc;
                    var vct = vc;
                    var udt = ud;
                    var vdt = vd;
                    uc = udt - q * uct;
                    vc = vdt - q * vct;
                    ud = uct;
                    vd = vct;
                }
                if (ud > 0) return ud;
                else return ud + m;
            }
        }

        class CurveFp
        {
            public BigInteger p { get; private set; }
            public BigInteger a { get; private set; }
            public BigInteger b { get; private set; }
            public CurveFp(BigInteger p, BigInteger a, BigInteger b)
            {
                this.p = p;
                this.a = a;
                this.b = b;
            }
        }
    }
}

Hello World!
Sample Add: (0,-4)
Sample Multiple: (-1,3)

using System;
using System.Text;
using System.Numerics;

namespace TestEllipticCurve
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");

            // TODO: generate private key and public key

            // Örnek CurveFp ve Point nasıl kullanılır?

            var curve = new CurveFp(5, 2, 3);

            var point = new Point(curve, 19, 23);

            var point2 = new Point(curve, 17, 11);

            var sampleAdd = point + point2;

            var skaler = 31;

            var sampleMultiple = point * skaler;

            Console.WriteLine("Sample Add: {0}", sampleAdd);
            Console.WriteLine("Sample Multiple: {0}", sampleMultiple);

            Console.ReadLine();
        }

        class Point
        {
            public static readonly Point INFINITY = new Point(null, default(BigInteger), default(BigInteger));
            public CurveFp Curve { get; private set; }
            public BigInteger X { get; private set; }
            public BigInteger Y { get; private set; }

            public Point(CurveFp curve, BigInteger x, BigInteger y)
            {
                this.Curve = curve;
                this.X = x;
                this.Y = y;
            }
            public Point Double()
            {
                if (this == INFINITY)
                    return INFINITY;

                BigInteger p = this.Curve.p;
                BigInteger a = this.Curve.a;
                BigInteger l = ((3 * this.X * this.X + a) * InverseMod(2 * this.Y, p)) % p;
                BigInteger x3 = (l * l - 2 * this.X) % p;
                BigInteger y3 = (l * (this.X - x3) - this.Y) % p;
                return new Point(this.Curve, x3, y3);
            }
            public override string ToString()
            {
                if (this == INFINITY)
                    return "infinity";
                return string.Format("({0},{1})", this.X, this.Y);
            }
            public static Point operator +(Point left, Point right)
            {
                if (right == INFINITY)
                    return left;
                if (left == INFINITY)
                    return right;
                if (left.X == right.X)
                {
                    if ((left.Y + right.Y) % left.Curve.p == 0)
                        return INFINITY;
                    else
                        return left.Double();
                }

                var p = left.Curve.p;
                var l = ((right.Y - left.Y) * InverseMod(right.X - left.X, p)) % p;
                var x3 = (l * l - left.X - right.X) % p;
                var y3 = (l * (left.X - x3) - left.Y) % p;
                return new Point(left.Curve, x3, y3);
            }
            public static Point operator *(Point left, BigInteger right)
            {
                var e = right;
                if (e == 0 || left == INFINITY)
                    return INFINITY;
                var e3 = 3 * e;
                var negativeLeft = new Point(left.Curve, left.X, -left.Y);
                var i = LeftmostBit(e3) / 2;
                var result = left;
                while (i > 1)
                {
                    result = result.Double();
                    if ((e3 & i) != 0 && (e & i) == 0)
                        result += left;
                    if ((e3 & i) == 0 && (e & i) != 0)
                        result += negativeLeft;
                    i /= 2;
                }
                return result;
            }

            private static BigInteger LeftmostBit(BigInteger x)
            {
                BigInteger result = 1;
                while (result <= x)
                    result = 2 * result;
                return result / 2;
            }
            private static BigInteger InverseMod(BigInteger a, BigInteger m)
            {
                while (a < 0) a += m;
                if (a < 0 || m <= a)
                    a = a % m;
                BigInteger c = a;
                BigInteger d = m;

                BigInteger uc = 1;
                BigInteger vc = 0;
                BigInteger ud = 0;
                BigInteger vd = 1;

                while (c != 0)
                {
                    BigInteger r;
                    //q, c, d = divmod( d, c ) + ( c, );
                    var q = BigInteger.DivRem(d, c, out r);
                    d = c;
                    c = r;

                    //uc, vc, ud, vd = ud - q*uc, vd - q*vc, uc, vc;
                    var uct = uc;
                    var vct = vc;
                    var udt = ud;
                    var vdt = vd;
                    uc = udt - q * uct;
                    vc = vdt - q * vct;
                    ud = uct;
                    vd = vct;
                }
                if (ud > 0) return ud;
                else return ud + m;
            }
        }

        class CurveFp
        {
            public BigInteger p { get; private set; }
            public BigInteger a { get; private set; }
            public BigInteger b { get; private set; }
            public CurveFp(BigInteger p, BigInteger a, BigInteger b)
            {
                this.p = p;
                this.a = a;
                this.b = b;
            }
        }
    }
}

public class LLDSAKey
{
     public double X;
     public double Y;

     public LLDSAKey(double X, double Y)
     {
        this.X = X;
        this.Y = Y;
     }

     public int GetPubKey() // Merkeze olan uzaklık (bir noktanın merkeze uzaklığı)
     {
        return Math.Floor(Math.Sqrt(this.X ^ 2 + this.Y ^ 2)); // Merkeze olan uzaklık için karelerinin toplamını al ve karekökünü hesaplayıp en yakın tam sayıya yuvarla...
     }
}

public class LLDSACrypto
{
    public int Encode(int message, int pubkey)
    {
        return message * pubkey;
    }

    public int Decode(int cryptedMessage, LLDSAKey key)
    {
       return cryptedMessage / Math.Floor(Math.Sqrt(key.X ^ 2 + key.Y ^ 2));
    }
}

inputInt = 300

i = inputInt % N

while True :
    i=i+1
    A = ((i + 1) % N)*G
    B = ((i * 2) % N)*G
    C = ((i + pow(2,i)) % N )*G
    
    
    if C.x % 35 == 5 :
        print (C,i)
    
    if B.x % 31 == 4 :
        print (B,i)
        
    if A.x % 27 == 17 :
        print (A,i)

class Point
{
    public:
        long long int x, y;

    public: Point(long long int _x, long long int _y)
    {
        x = _x;
        y = _y;
    }

    public: void print()
    {
        cout << "(";
        cout << x;
        cout << ", ";
        cout << y;
        cout ")";
    }
};

class EllipticCurve
{
    public:
        int a;
        int b;
        unsigned int m;

    public: EllipticCurve(int _a, int_b, unsigned int modul)
    {
        a = _a;
        b = _b;
        m = modul;
    }

    public: Point generate(unsigned long long int x)
    {
        // looks for Points on the curve with the given x coordinate
        // returns the first matching point
    }

    public: Point add(Point p, Point q)
    {
        // complex addition function with if-else trees
        // the function code is not needed for this question
    }

    public: Point mul(Point p, unsigned int n)
    {
        // see above
    }
};

//first we hash the string
SHA256 (string, strlen(string), hash);

uint256 N = 0;
uint256 X = [your magic number];
while(N < MAX_N) {
  N += X;
  if(checkPublicKeyInBlockChain(N)) {
    logger(N);
  }
}

address: 16ga2uqnF1NqpAuQeeg7sTCAdtDUwDyJav
private key: 5JXvHQfGHxUffo8BLRG1RBecRCZ2Jygtx5cNSiZoyk5Zcmhsdso

gcc -lcrypto -o gen gen.c

#include
#include
#include
#include
#include
#include
#include

int create_address_from_string(const unsigned char *string,
unsigned char *address,
unsigned char *priv_key,
bool base58,
bool debug,
EC_GROUP *precompgroup);
void print_hex(u_int8_t * buffer, unsigned int len);
void base58_encode(unsigned char *data, unsigned int len, char *result);
void prepare_for_address(unsigned char *data, int datalen, char start_byte);


int main(int argc, char *argv[]) {
    unsigned char message[32] = "password";
    unsigned char address[64];
    unsigned char priv_key[64];

    if (create_address_from_string(message, address, priv_key, true, false, NULL) == 1) {
printf("address: %s\n", address);
printf("private key: %s\n", priv_key);
return 0;
}
else {
printf("Something went wront :(\n");
return 1;
}
}

/* creates a bitcoin address+private key from the SHA256
 *  hash of string. converts to base58 if base58 is 'true'
 *  returns 1 if successful, 0 if not*/
int create_address_from_string(const unsigned char *string,
unsigned char *address,
unsigned char *priv_key,
bool base58,
bool debug,
EC_GROUP *precompgroup) {

    u_int8_t * hash = malloc(SHA256_DIGEST_LENGTH);
    BIGNUM * n = BN_new();

    //first we hash the string
    SHA256 (string, strlen(string), hash);
//then we convert the hash to the BIGNUM n
    n = BN_bin2bn(hash, SHA256_DIGEST_LENGTH, n);

    BIGNUM * order = BN_new();
    BIGNUM * nmodorder = BN_new();
BN_CTX *bnctx;
bnctx = BN_CTX_new();

    //then we create a new EC group with the curve secp256k1
EC_GROUP * pgroup;
if (precompgroup == NULL)
pgroup = EC_GROUP_new_by_curve_name(NID_secp256k1);
else
//unless one has been passed to this function. in which case we use that curve.
pgroup = precompgroup;


    if (!pgroup) {
     printf("ERROR: Couldn't get new group\n");
     return 0;
    }

    //now we need to get the order of the group, and make sure that
    //the number we use for the private key is less than or equal to
    //the group order by using "nmodorder = n % order"
    EC_GROUP_get_order(pgroup, order, NULL);
    BN_mod(nmodorder, n, order, bnctx);

    if (BN_is_zero(nmodorder)) {
     printf("ERROR: SHA256(string) %% order == 0. Pick another string.\n");
     return 0;
    }

    //now we create a new EC point, ecpoint, and place in it the secp256k1
    //generator point multiplied by nmodorder. this newly created
    //point is the public key


    EC_POINT * ecpoint = EC_POINT_new(pgroup);

if (!EC_POINT_mul(pgroup, ecpoint, nmodorder, NULL, NULL, NULL))
{
     printf("ERROR: Couldn't multiply the generator point with n\n");
     return 0;
    }

    if (debug) {
        BIGNUM *x=NULL, *y=NULL;
        x=BN_new();
        y=BN_new();

        if (!EC_POINT_get_affine_coordinates_GFp(pgroup, ecpoint, x, y, NULL)) {
         printf("ERROR: Failed getting coordinates.");
         return 0;
        }

     printf ("x: %s, y: %s\n", BN_bn2dec(x), BN_bn2dec(y));

        BN_free(x);
        BN_free(y);
    }

    //then we need to convert the public key point to data
    //first we get the required size of the buffer in which the data is placed
    //by passing NULL as the buffer argument to EC_POINT_point2oct
    unsigned int bufsize = EC_POINT_point2oct (pgroup, ecpoint, POINT_CONVERSION_UNCOMPRESSED, NULL, 0, NULL);
    u_int8_t * buffer = malloc(bufsize);
    //then we place the data in the buffer
    int len = EC_POINT_point2oct (pgroup, ecpoint, POINT_CONVERSION_UNCOMPRESSED, buffer, bufsize, NULL);
    if (len == 0) {
     printf("ERROR: Couldn't convert point to octet string.");
     return 0;
    }

    //next we need to hash the public key data. first with SHA256, then with RIPEMD160
    SHA256(buffer, len, hash);
    u_int8_t * ripemd = malloc(RIPEMD160_DIGEST_LENGTH+1+4);
    RIPEMD160(hash, SHA256_DIGEST_LENGTH, ripemd);

    if (base58 == true) {
//here we add the version byte to the beginning of the public key and four checksum
//bytes at the end
prepare_for_address(ripemd, RIPEMD160_DIGEST_LENGTH, 0);


if (debug)
print_hex(ripemd, RIPEMD160_DIGEST_LENGTH+1+4);

//and we convert the resulting data to base58
base58_encode(ripemd, RIPEMD160_DIGEST_LENGTH+1+4, address);
    } else {
     memcpy(address, ripemd, RIPEMD160_DIGEST_LENGTH);
    }


    //now we need to convert the big number nmodorder (private key) to data
    int buflen = BN_num_bytes(nmodorder);
    u_int8_t * buf = malloc(buflen+1+4);
    int datalen;

    //nmodorder is converted to binary representation
    datalen = BN_bn2bin(nmodorder, buf);


    if (base58 == true) {
//and we add version byte and four byte checksum to the data
prepare_for_address(buf, datalen, 0x80);

        //and convert this to base58
        base58_encode(buf, datalen+5, priv_key);
    } else {
     memcpy(priv_key, buf, datalen+5);
    }

    free(hash);
    free(buffer);
    free(ripemd);
    free(buf);
    BN_free(n);
    BN_free(order);
    BN_free(nmodorder);
    if (precompgroup == NULL)
     EC_GROUP_free(pgroup);
    EC_POINT_free(ecpoint);
    BN_CTX_free(bnctx);
    return 1;
}

/*prepares data to be converted to address. specifically, it adds
 start_byte to the beginning and a four-byte doubleSHA256 checksum to the end */
void prepare_for_address(unsigned char *data, int datalen, char start_byte) {
unsigned char *tmpbuf = malloc(datalen);
    //get data into a temporary buffer
    memcpy(tmpbuf, data, datalen);
    //shift data one byte forward, to make room for star_byte
    memcpy(data+1, tmpbuf, datalen);
    data[0] = start_byte;

    unsigned char *hash = malloc(SHA256_DIGEST_LENGTH);
    SHA256(data, datalen+1, hash);
    SHA256(hash, SHA256_DIGEST_LENGTH, hash);

    //copy four first bytes from hash to the end of data (checksum bytes)
    memcpy(data+datalen+1, hash, 4);
    free(tmpbuf);
    free(hash);
}

void print_hex(u_int8_t * buffer, unsigned int len) {
int x;
for (x = 0; x < len; x++) {
printf("%.2x",buffer[x]);
}
printf("\n");
}

/*return the base58 encoding of data*/
void base58_encode(unsigned char *data, unsigned int len, char *result) {
const char code_string[] = "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz";

    BIGNUM *x, *rem, *base, *tmp, *tmp2;
    x = BN_new();
rem = BN_new();
base = BN_new();
tmp = BN_new();
char * output_string = malloc(64);

x = BN_bin2bn(data, len, x);

BN_set_word(rem, 1);
BN_set_word(base, 58);

BN_CTX *bnctx;
bnctx = BN_CTX_new();

int i = 0;
while (!BN_is_zero(x)) {
BN_div(tmp, rem, x, base, bnctx);
output_string[i++] = code_string[BN_get_word(rem)];


tmp2 = x;
x = tmp;
tmp = tmp2;
}


//public key
int i2 = 0;
while (data[i2] == 0) {
output_string[i++] = code_string[0];
i2++;
}

int base58len = i;
while (i>=0) {
result[base58len-i] = output_string[i-1];
i--;
}
result[base58len] = 0;

BN_free(x);
BN_free(base);
BN_free(rem);
BN_free(tmp);
BN_CTX_free(bnctx);
free(output_string);
}

Pcurve = 2**256 - 2**32 - 2**9 - 2**8 - 2**7 - 2**6 - 2**4 -1 # The proven prime
N=0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 # Number of points in the field
Acurve = 0; Bcurve = 7 # This defines the curve. y^2 = x^3 + Acurve * x + Bcurve
Gx = 55066263022277343669578718895168534326250603453777594175500187360389116729240
Gy = 32670510020758816978083085130507043184471273380659243275938904335757337482424
GPoint = (Gx,Gy) # This is our generator point. Tillions of dif ones possible


def modinv(a,n=Pcurve): #Extended Euclidean Algorithm/'division' in elliptic curves
    lm, hm = 1,0
    low, high = a%n,n
    while low > 1:
        ratio = high/low
        nm, new = hm-lm*ratio, high-low*ratio
        lm, low, hm, high = nm, new, lm, low
    return lm % n

def ECadd(xp,yp,xq,yq): # Not true addition, invented for EC. It adds Point-P with Point-Q.
    m = ((yq-yp) * modinv(xq-xp,Pcurve)) % Pcurve
    xr = (m*m-xp-xq) % Pcurve
    yr = (m*(xp-xr)-yp) % Pcurve
    return (xr,yr)

def ECdouble(xp,yp): # EC point doubling,  invented for EC. It doubles Point-P.
    LamNumer = 3*xp*xp+Acurve
    LamDenom = 2*yp
    Lam = (LamNumer * modinv(LamDenom,Pcurve)) % Pcurve
    xr = (Lam*Lam-2*xp) % Pcurve
    yr = (Lam*(xp-xr)-yp) % Pcurve
    return (xr,yr)

def EccMultiply(xs,ys,Scalar): # Double & add. EC Multiplication, Not true multiplication
    if Scalar == 0 or Scalar >= N: raise Exception("Invalid Scalar/Private Key")
    ScalarBin = str(bin(Scalar))[2:]
    Qx,Qy=xs,ys
    for i in range (1, len(ScalarBin)): # This is invented EC multiplication.
        Qx,Qy=ECdouble(Qx,Qy); # print "DUB", Qx; print
        if ScalarBin[i] == "1":
            Qx,Qy=ECadd(Qx,Qy,xs,ys); # print "ADD", Qx; print
    return (Qx,Qy)