Package poly1305 provides a Go wrapper around floodyberry's optimized implementation of Poly1305. Poly1305 is a message authentication code (MAC) 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 Poly1305 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.