pairid module

Library of cryptographic key generation and data preparation procedures associated with the PAIR protocol.

The example below illustrates how the functions can be used in conjunction with one another.

>>> ks = key_salt()
>>> ka = key_commutative()
>>> kb = key_commutative()
>>> ciphertext_s = salt(ks, 'alice@example.com')
>>> ciphertext_sa = encrypt(ka, ciphertext_s)
>>> ciphertext_sab = encrypt(kb, ciphertext_sa)
>>> decrypt(ka, ciphertext_sab) == encrypt(kb, ciphertext_s)
True

key_salt() → bytes

Generate a secret salt.

>>> isinstance(key_salt(), bytes)
True

key_commutative() → bytes

Generate a secret commutative encryption key.

>>> isinstance(key_commutative(), bytes)
True

salt(salt: bytes, plaintext: str) → bytes

Salt a string using a secret salt.

>>> kc = key_salt()
>>> ciphertext = salt(kc, 'alice@example.com')
>>> isinstance(ciphertext, bytes) and len(ciphertext) == 32
True

encrypt(key: bytes, plaintext: Union[str, bytes]) → bytes

Encrypt a string using a secret commutative key.

>>> kc = key_commutative()
>>> ciphertext = encrypt(kc, 'alice@example.com')
>>> isinstance(ciphertext, bytes) and len(ciphertext) == 32
True

decrypt(key: bytes, ciphertext: bytes) → bytes

Remove a layer of encryption (corresponding to they supplied secret commutative key) from a ciphertext.

>>> ka = key_commutative()
>>> kb = key_commutative()
>>> ciphertext = encrypt(ka, 'alice@example.com')
>>> ciphertext = encrypt(kb, ciphertext)
>>> decrypt(ka, ciphertext) == encrypt(kb, 'alice@example.com')
True