sha1.BlockSize
// The blocksize of SHA-1 in bytes.
const BlockSize = 64
sha1.Size
// The size of a SHA-1 checksum in bytes.
const Size = 20
sha1.New
// New returns a new hash.Hash computing the SHA1 checksum. The Hash also
// implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
// marshal and unmarshal the internal state of the hash.
func New() hash.Hash
sha1.Sum
// Sum returns the SHA-1 checksum of the data.
func Sum(data []byte) [Size]byte