Experimenting with Encryption

Suggestions 1-4 refer to program ASM_Encrypt.

  1. Test it with your own text files.
  2. Increase the encryption security by doubling its number of keys to 16.
  3. Increase its security by adding a NOT operation. (NOT is a bitwise logical operator that changes every 0 in the operand to 1 and every 1 to 0. Application of the NOT operation a second time regenerates the original value of the operand).
  4. Increase its efficiency by encrypting 4 bytes at a time.
  5. Write your own program with in-line assembler code to:
    1. encrypt and store a password entered by the user;
    2. encrypt and validate the same password re-entered by the user;
    3. encrypt a text file using your own algorithm;
    4. decrypt your encrypted file.
Programming - a skill for life!

Demonstrations of encryption and decryption with and without assembler code