Custom Cipher Encryption & Decryption

Description

This Python program encrypts and decrypts messages using a dynamic 62-column matrix. A passkey generates a shifted character sequence, while a key encodes messages securely.

Features

• Uses a matrix generated from a passkey.
• Encrypts and decrypts messages.
• Supports A-Z, a-z, 0-9 characters.
• Handles missing characters.

How It Works

Step 1: Generate the Matrix

1. Remove passkey characters from the base sequence.
2. Create a shifted 6×6 matrix.

Row	Shift	Sequence
0	0	ba1AB2
1	1	a1AB2b
2	2	1AB2ba

Step 2: Encrypting

1. Match key length to message.
2. Locate characters in matrix rows.
3. Find intersection for encryption.

Message	Key	Encrypted
A	B	1
1	2	A
b	B	a

Encrypted Message: 1Aa

Step 3: Decrypting

Encrypted	Key	Decrypted
1	B	A
A	2	1
a	B	b

Decrypted Message: A1b

Running the Program

1. Clone repository:

   git clone git remote add origin https://github.com/jyotiska222/Custom-Cipher-Encryption-Decryption.git
   cd Custom-Cipher-Encryption-Decryption

2. Run the script:

   python cipher.py

3. Input required values.

Example

Encryption

Enter the Passkey: pas
Choose 'e' for encrypt or 'd' for decrypt: e
Enter the MESSAGE: SecretMsg
Enter the KEY OF THAT MESSAGE: key
Encrypted Message: 7sPRsf1gT

Decryption

Enter the Passkey: pas
Choose 'e' for encrypt or 'd' for decrypt: d
Enter the ENCRYPTED MESSAGE: 7sPRsf1gT
Enter the KEY OF THE MESSAGE: key
Decrypted Message: SecretMsg

Security Strength

• A 4-character passkey has 62⁴ = 14.7 million combinations.
• A matching key also has 62⁴ combinations.
• Total brute-force attempts: 218 trillion.

Notes

• Passkey and key must match for decryption.
• Case-sensitive.
• Non-alphanumeric characters remain unchanged.

For any Suggestions [email protected]

MY INSTAGRAM PASSWORD: PLgf6B@# (Encrypted) If you get it, You have it