License Key Generation Algorithm C
The license key template is a string of characters that represent what actions will be taken when the key is created and decoded. Two types of templates are Bytes and Bits. Bytes are used when the key will be a simple key that does not require a lot of fields and data encoding. Symmetric-key algorithm A cryptographic algorithm that uses the same secret key for its operation and(if applicable) for reversing the effects of the operation (e.g., an HMAC key for keyed hashing or an AES key for encryption and decryption); also known as a secret-key algorithm. If it matches, it's a valid license. If you run low on licenses, release a new version with more strings. Using just the first 96-bits of the SHA1 hash is adequate. So 10,000 licenses would take under 120KB. Algorithmic generation of keys or creation of a key generator would be impossible.