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cryptolib – cryptographic ciphers

Cryptographic ciphers.

class cryptolib.aes(key, mode, IV: Any | None = None)

__init__(key, mode, IV: Any | None = None)

Initialize cipher object, suitable for encryption/decryption. Note: after initialization, cipher object can be use only either for encryption or decryption. Running decrypt() operation after encrypt() or vice versa is not supported.

Parameters are:

• key is an encryption/decryption key (bytes-like).

• mode is:

  • 1 (or cryptolib.MODE_ECB if it exists) for Electronic Code Book (ECB).

  • 2 (or cryptolib.MODE_CBC if it exists) for Cipher Block Chaining (CBC).

  • 6 (or cryptolib.MODE_CTR if it exists) for Counter mode (CTR).

• IV is an initialization vector for CBC mode.

• For Counter mode, IV is the initial value for the counter.

decrypt(in_buf, out_buf: Any | None = None)

Like encrypt(), but for decryption.

encrypt(in_buf, out_buf: Any | None = None)

Encrypt in_buf. If no out_buf is given result is returned as a newly allocated bytes object. Otherwise, result is written into mutable buffer out_buf. in_buf and out_buf can also refer to the same mutable buffer, in which case data is encrypted in-place.