1. Encryption Theory CSC380 – Flint Joasaint, Marcial White

2. The Algorithm RPG Program CCED01 Originally intended for 16 digit keys, We’ve extended it to 24 digits (A-Z) Originally intended for 16 digit keys, We’ve extended it to 24 digits (A-Z) abcdefghijklmnopqrstuvwxyz bcdefghijklmnopqrstuvwxyza cdefghijklmnopqrstuvwxyzab defghijklmnopqrstuvwxyzabc efghijklmnopqrstuvwxyzabcd fghijklmnopqrstuvwxyzabcde ghijklmnopqrstuvwxyzabcdef hijklmnopqrstuvwxyzabcdefg ijklmnopqrstuvwxyzabcdefgh jklmnopqrstuvwxyzabcdefghi klmnopqrstuvwxyzabcdefghij abcdefghijklmnopqrstuvwxyz bcdefghijklmnopqrstuvwxyza cdefghijklmnopqrstuvwxyzab defghijklmnopqrstuvwxyzabc efghijklmnopqrstuvwxyzabcd fghijklmnopqrstuvwxyzabcde ghijklmnopqrstuvwxyzabcdef hijklmnopqrstuvwxyzabcdefg ijklmnopqrstuvwxyzabcdefgh jklmnopqrstuvwxyzabcdefghi klmnopqrstuvwxyzabcdefghij lmnopqrstuvwxyzabcdefghijk mnopqrstuvwxyzabcdefghijkl nopqrstuvwxyzabcdefghijklm opqrstuvwxyzabcdefghijklmn pqrstuvwxyzabcdefghijklmno qrstuvwxyzabcdefghijklmnop rstuvwxyzabcdefghijklmnopq stuvwxyzabcdefghijklmnopqr tuvwxyzabcdefghijklmnopqrs uvwxyzabcdefghijklmnopqrst vwxyzabcdefghijklmnopqrstu lmnopqrstuvwxyzabcdefghijk mnopqrstuvwxyzabcdefghijkl nopqrstuvwxyzabcdefghijklm opqrstuvwxyzabcdefghijklmn pqrstuvwxyzabcdefghijklmno qrstuvwxyzabcdefghijklmnop rstuvwxyzabcdefghijklmnopq stuvwxyzabcdefghijklmnopqr tuvwxyzabcdefghijklmnopqrs uvwxyzabcdefghijklmnopqrst vwxyzabcdefghijklmnopqrstu Etc…

3. Algorithm Continued … Program CCED01 has only one parameter: a 25-byte character value. The first 24 bytes contain a left-justified letter. The last byte must contain E to encrypt or D to decrypt. CALL PGM (CCED01) PARM (‘Hello World E') Will yield “HDJKK QHJCT” CALL PGM (CCED01) PARM (‘HDJKK QHJCT D') Will decrypt the message.

4. Algorithm Continued Array Element abcdefghijklmnopqrstuvwxyz bcdefghijklmnopqrstuvwxyza cdefghijklmnopqrstuvwxyzab defghijklmnopqrstuvwxyzabc efghijklmnopqrstuvwxyzabcd fghijklmnopqrstuvwxyzabcde ghijklmnopqrstuvwxyzabcdef hijklmnopqrstuvwxyzabcdefg ijklmnopqrstuvwxyzabcdefgh jklmnopqrstuvwxyzabcdefghi klmnopqrstuvwxyzabcdefghij Input Letter H D J K Q H J C T Output Letter H E L O W O R L D For decryption …

5. The Interface

6. The Code public class simple { // Might randomize placement of characters in array later string[] characters = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"}; string[] cypertext = {"!","@","#","$","%",">","&","*","(",")","!","@","#","$","%",">","&","*","(",")","&","*","(",")"}; public simpleencrypt() { } public string EncryptString(string Data, string Key) { if(Data.Length == 0) throw new ArgumentException("Hey Your key must be at please 1 digit."); uint[] formattedKey = FormatKey(Key); if(Data.Length%2!=0) Data += '\0'; byte[] dataBytes = System.Text.ASCIIEncoding.ASCII.GetBytes(Data); string changedtext = string.Empty; uint[] tempData = new uint[2]; for(int i=0; i

7. The Code, Cont… public class simple { // Might randomize placement of characters in array later string[] characters = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z "}; string[] cypertext = {"!","@","#","$","%",">","&","*","(",")","!","@","#","$","%",">","&","*","(",")","&","*","(",")"}; public simpleencrypt() { } public string EncryptString(string Data, string Key) { if(Data.Length == 0) throw new ArgumentException("Hey Your key must be at please 1 digit."); uint[] formattedKey = FormatKey(Key);

8. Code cont … if(Data.Length%2!=0) Data += '\0'; byte[] dataBytes = System.Text.ASCIIEncoding.ASCII.GetBytes(Data); string changedtext = string.Empty; uint[] tempData = new uint[2]; for( int ix = 0; ix < data.Count; ++ix ) { str = ( string )data[ ix ]; sentences[ ix ] = str.Split( char ); } changedtext += Util.ConvertUIntToString(tempData[0]) + Util.ConvertUIntToString(tempData[1]); } return changedtext; }