How to implement XOR cipher with repeating key in JavaScript for simple message encoding?
I need a simple, lightweight way to encode/decode messages using XOR with a repeating key, then Base64 encode the result for safe transmission.
Requirements:
- Works in browser JavaScript
- Uses a repeating key (key cycles if shorter than message)
- Output should be Base64 encoded
- Must be reversible (same function encrypts and decrypts)
What's the cleanest implementation?