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CRYPTOGRAPHY MANAGEMENT KIT CONTENTS

A Guide to Cryptography

A complete introduction to cryptography and its application.

Training Presentation

A full 'executive' presentation explaining both background and practical issues.

Microgaming Security

The main Microgaming security technologies in gambling industry.

Cryptography Audit Kit

Designed specifically to help you audit a cryptographic based system or application.

Cryptography FAQ Sheets

A unique reference covering the full gamut of issues in simple Q&A style.

Source Library for Base Algorithms Example source code,for: Why re-invent the wheel?

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The Cryptography Management Kit

Cryptography Tutorial and Management Kit

A comprehensive kit comprising an introductory presentation, a comprehensive guide, a detailed FAQ reference, an audit kit and base source for several algorithms.

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Only $199

The Cryptography Management Kit includes basic sample source code for the RSA algorithm. The following samples help to illustrate the depth and quality of this:

Typical Pages:

Mukiply two numbers together. If the lengths of the two numbers are M and N, the
length of the result is (M+N).

int AK_RSA_Mul(unsigned short int ul],
unsigned short int v[],
unsigned short int w[])
{

  • short int m,n,i,j,su, sv;
  • unsigned int k,t;
  • n = u[0] & 32767; su = u[0] >> 15;
  • m= v[0] & 32767; sv = v[0] >> 15;

if (m == 0 || n == 0)
{

  • w[0] = 0;
  • return (0);

}
for (i = m+; i <= m+n; i++) wli] = 0; for (j =m; j > 0; j–)
{

  • k= 0;
  • for (i =n; i > 0; i–)
    {
    • t= u[i] * v[j] + wla + 5] +k;
    • w [i + j] = t & 65535;
    • k= t >> 16;

}
w[j] =k;
}

  • w[0] = m+n;
  • AK_RSA_Normalise (w);
  • if (su != sv} w[0] |= 32768;
  • return(m + n);

}

Test if a specific bit is on or off. This is needed by the modular power routine to
determine whether to square and multiply, or just square.

int AK_RSA_Test_Bit (unsigned short int [ul],
short int bit)
{
  • unsigned int k;
  • k = ull + (bit>>4)) & (32768>>(bit & 15));
  • if (k ! = 0) return(1);
  • return (0);

}

The modular power routine is the basis for RSA encryption and decryption, so all
we have to do now is compute RSA key pairs!

int AK_RSA Mod_Power(unsigned short int Bas[],
unsigned short int Pow[],
unsigned short int Mod[],
unsigned short int Res[])
{
  • short int i,m,n;
  • unsigned short int q[512],t[512],w[512];
  • Res[0] = 1;
  • Res[1] = 1;
  • for (4 = 0; i <= Bas[0]; i++) t[i] = Bas[i];
  • n = (Pow[0] << 4) - 1;
  • m = 0;
  • while (AK_RSA_Test_Bit(Pow,m) == 0) m++;
  • for (i =n; i >= m; i–)
    {
    • if (AK_RSA_Test_Bit (Pow, i) == 1)

      • {

      • if (Res[0] == 1) AK_RSA Short _Mul(t,Res[1],w); else
        AK_RSA_ Mul (Res, t,w);
        AK_RSA_Div(w,Mod,q,Res};

      • }

    • AK_RSA Mul(t,t,w);
    • AK_RSA_Div (x, Mod, q, t);

    }
    return (0);

}

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