poly1305.TagSize
// TagSize is the size, in bytes, of a poly1305 authenticator.
//
// For use with golang.org/x/crypto/chacha20poly1305, chacha20poly1305.Overhead
// can be used instead.
const TagSize = 16
poly1305.New
// New returns a new MAC computing an authentication
// tag of all data written to it with the given key.
// This allows writing the message progressively instead
// of passing it as a single slice. Common users should use
// the Sum function instead.
//
// The key must be unique for each message, as authenticating
// two different messages with the same key allows an attacker
// to forge messages at will.
func New(key *[32]byte) *MAC
poly1305.Sum
// Sum generates an authenticator for msg using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte)
poly1305.Verify
// Verify returns true if mac is a valid authenticator for m with the given key.
func Verify(mac *[16]byte, m []byte, key *[32]byte) bool