aesccm

Documentation

Overview

Package aesccm implements content encryption algorithm AES-CCM for COSE as defined in RFC9053. https://datatracker.ietf.org/doc/html/rfc9053#name-aes-ccm.

(c) 2022-present, LDC Labs, Inc. All rights reserved. See the file LICENSE for licensing terms.

Package ccm implements a CCM, Counter with CBC-MAC as per RFC 3610.

See https://tools.ietf.org/html/rfc3610

This code was lifted from https://github.com/qwerty-iot/dtls/blob/a3300364a283fcb490d28a93d7fcfa7ba437fbbe/ccm/ccm.go and as such was not written by the Pions authors. Like Pions this code is licensed under MIT.

Index

• func CheckKey(k key.Key) error
• func GenerateKey(alg int) (key.Key, error)
• func KeyFrom(alg int, k []byte) (key.Key, error)
• func MaxNonceLength(pdatalen int) int
• func New(k key.Key) (key.Encryptor, error)
• type CCM
  • func NewCCM(b cipher.Block, tagsize, noncesize int) (CCM, error)

Functions

func CheckKey

func CheckKey(k key.Key) error

CheckKey checks whether the given key is a valid AES-CCM key.

func GenerateKey

func GenerateKey(alg int) (key.Key, error)

GenerateKey generates a new Key with given algorithm for AES-CCM.

func KeyFrom

func KeyFrom(alg int, k []byte) (key.Key, error)

KeyFrom returns a Key with given algorithm and bytes for AES-CCM.

func MaxNonceLength

func MaxNonceLength(pdatalen int) int

MaxNonceLength returns the maximum nonce length for a given plaintext length. A return value <= 0 indicates that plaintext length is too large for any nonce length.

func New

func New(k key.Key) (key.Encryptor, error)

New creates a key.Encryptor for the given AES-CCM key.

Types

type CCM

type CCM interface {
	cipher.AEAD
	// MaxLength returns the maxium length of plaintext in calls to Seal.
	// The maximum length of ciphertext in calls to Open is MaxLength()+Overhead().
	// The maximum length is related to CCM's `L` parameter (15-noncesize) and
	// is 1<<(8*L) - 1 (but also limited by the maxium size of an int).
	MaxLength() int
}

CCM is a block cipher in Counter with CBC-MAC mode. Providing authenticated encryption with associated data via the cipher.AEAD interface.

func NewCCM

func NewCCM(b cipher.Block, tagsize, noncesize int) (CCM, error)

NewCCM returns the given 128-bit block cipher wrapped in CCM. The tagsize must be an even integer between 4 and 16 inclusive and is used as CCM's `M` parameter. The noncesize must be an integer between 7 and 13 inclusive, 15-noncesize is used as CCM's `L` parameter.