onetimeauth

Overview ¶

Package onetimeauth provides primitives for secret-key, single-message authentication.

The onetimeauth function, viewed as a function of the message for a uniform random key, is designed to meet the standard notion of unforgeability after a single message. After the sender authenticates one message, an attacker cannot find authenticators for any other messages.

The sender must not use onetimeauth to authenticate more than one message under the same key. Authenticators for two messages under the same key should be expected to reveal enough information to allow forgeries of authenticators on other messages.

The selected primitive is poly1305, an authenticator specified in "Cryptography in NaCl", Section 9. This authenticator is proven to meet the standard notion of unforgeability after a single message.

This package is interoperable with NaCL: https://nacl.cr.yp.to/onetimeauth.html