hmac

Documentation

Overview

Package hmac implements the Keyed-Hash Message Authentication Code (HMAC) computation functions.

An HMAC is a cryptographic hash that uses a key to sign a message. The receiver verifies the hash by recomputing it using the same key.

The computed HMAC is represented as an hash.(Imprint).

Index

• type Hasher
  • func New(alg ksihash.Algorithm, key []byte) (h *Hasher, e error)
  • func (h *Hasher) BlockSize() int
  • func (h *Hasher) Imprint() (ksihash.Imprint, error)
  • func (h *Hasher) Reset()
  • func (h *Hasher) Size() int
  • func (h *Hasher) Write(p []byte) (int, error)

Types

type Hasher

type Hasher struct {
	// contains filtered or unexported fields
}

Hasher is the message authentication computation object.

func New

func New(alg ksihash.Algorithm, key []byte) (h *Hasher, e error)

New returns a new HMAC hash using the given hash.Algorithm type and key.

func (*Hasher) BlockSize

func (h *Hasher) BlockSize() int

BlockSize returns the size of the data block the underlying hash algorithm operates upon in bytes.

func (*Hasher) Imprint

func (h *Hasher) Imprint() (ksihash.Imprint, error)

Imprint returns KSI imprint for the current computation. It does not change the underlying hash state.

func (*Hasher) Reset

func (h *Hasher) Reset()

Reset resets the hasher to its initial state.

func (*Hasher) Size

func (h *Hasher) Size() int

Size return the resulting digest length in bytes.

func (*Hasher) Write

func (h *Hasher) Write(p []byte) (int, error)

Write (via the embedded io.Writer interface) adds more data to the running hash. In case of KsiInvalidArgumentError error (e.g. h is nil) function returns non standard -1 as count of bytes written.