ecies

Documentation

Index

• Variables
• func AddParamsForCurve(curve elliptic.Curve, params *ECIESParams)
• func Encrypt(rand io.Reader, pub *PublicKey, m, s1, s2 []byte) (ct []byte, err error)
• func MaxSharedKeyLength(pub *PublicKey) int
• type ECIESParams
  • func ParamsFromCurve(curve elliptic.Curve) (params *ECIESParams)
• type PrivateKey
  • func GenerateKey(rand io.Reader, curve elliptic.Curve, params *ECIESParams) (prv *PrivateKey, err error)
  • func ImportECDSA(prv *ecdsa.PrivateKey) *PrivateKey
  • func (prv *PrivateKey) Decrypt(c, s1, s2 []byte) (m []byte, err error)
  • func (prv *PrivateKey) ExportECDSA() *ecdsa.PrivateKey
  • func (prv *PrivateKey) GenerateShared(pub *PublicKey, skLen, macLen int) (sk []byte, err error)
• type PublicKey
  • func ImportECDSAPublic(pub *ecdsa.PublicKey) *PublicKey
  • func (pub *PublicKey) ExportECDSA() *ecdsa.PublicKey

Variables

var (
	ErrImport                     = fmt.Errorf("ecies: failed to import key")
	ErrInvalidCurve               = fmt.Errorf("ecies: invalid elliptic curve")
	ErrInvalidPublicKey           = fmt.Errorf("ecies: invalid public key")
	ErrSharedKeyIsPointAtInfinity = fmt.Errorf("ecies: shared key is point at infinity")
	ErrSharedKeyTooBig            = fmt.Errorf("ecies: shared key params are too big")
)

var (
	ErrSharedTooLong  = fmt.Errorf("ecies: shared secret is too long")
	ErrInvalidMessage = fmt.Errorf("ecies: invalid message")
)

var (
	DefaultCurve                  = ethcrypto.S256()
	ErrUnsupportedECDHAlgorithm   = fmt.Errorf("ecies: unsupported ECDH algorithm")
	ErrUnsupportedECIESParameters = fmt.Errorf("ecies: unsupported ECIES parameters")
	ErrInvalidKeyLen              = fmt.Errorf("ecies: invalid key size (> %d) in ECIESParams", maxKeyLen)
)

var (
	ECIES_AES128_SHA256 = &ECIESParams{
		Hash:      sha256.New,
		hashAlgo:  crypto.SHA256,
		Cipher:    aes.NewCipher,
		BlockSize: aes.BlockSize,
		KeyLen:    16,
	}

	ECIES_AES256_SHA256 = &ECIESParams{
		Hash:      sha256.New,
		hashAlgo:  crypto.SHA256,
		Cipher:    aes.NewCipher,
		BlockSize: aes.BlockSize,
		KeyLen:    32,
	}

	ECIES_AES256_SHA384 = &ECIESParams{
		Hash:      sha512.New384,
		hashAlgo:  crypto.SHA384,
		Cipher:    aes.NewCipher,
		BlockSize: aes.BlockSize,
		KeyLen:    32,
	}

	ECIES_AES256_SHA512 = &ECIESParams{
		Hash:      sha512.New,
		hashAlgo:  crypto.SHA512,
		Cipher:    aes.NewCipher,
		BlockSize: aes.BlockSize,
		KeyLen:    32,
	}
)

Functions

func AddParamsForCurve

func AddParamsForCurve(curve elliptic.Curve, params *ECIESParams)

func Encrypt

func Encrypt(rand io.Reader, pub *PublicKey, m, s1, s2 []byte) (ct []byte, err error)

Encrypt encrypts a message using ECIES as specified in SEC 1, 5.1.

s1 and s2 contain shared information that is not part of the resulting ciphertext. s1 is fed into key derivation, s2 is fed into the MAC. If the shared information parameters aren't being used, they should be nil.

func MaxSharedKeyLength

func MaxSharedKeyLength(pub *PublicKey) int

MaxSharedKeyLength returns the maximum length of the shared key the public key can produce.

Types

type ECIESParams

type ECIESParams struct {
	Hash func() hash.Hash // hash function

	Cipher    func([]byte) (cipher.Block, error) // symmetric cipher
	BlockSize int                                // block size of symmetric cipher
	KeyLen    int                                // length of symmetric key
	// contains filtered or unexported fields
}

func ParamsFromCurve

func ParamsFromCurve(curve elliptic.Curve) (params *ECIESParams)

ParamsFromCurve selects parameters optimal for the selected elliptic curve. Only the curves P256, P384, and P512 are supported.

type PrivateKey

type PrivateKey struct {
	PublicKey
	D *big.Int
}

PrivateKey is a representation of an elliptic curve private key.

func GenerateKey

func GenerateKey(rand io.Reader, curve elliptic.Curve, params *ECIESParams) (prv *PrivateKey, err error)

Generate an elliptic curve public / private keypair. If params is nil, the recommended default parameters for the key will be chosen.

func ImportECDSA

func ImportECDSA(prv *ecdsa.PrivateKey) *PrivateKey

Import an ECDSA private key as an ECIES private key.

func (*PrivateKey) Decrypt

func (prv *PrivateKey) Decrypt(c, s1, s2 []byte) (m []byte, err error)

Decrypt decrypts an ECIES ciphertext.

func (*PrivateKey) ExportECDSA

func (prv *PrivateKey) ExportECDSA() *ecdsa.PrivateKey

Export an ECIES private key as an ECDSA private key.

func (*PrivateKey) GenerateShared

func (prv *PrivateKey) GenerateShared(pub *PublicKey, skLen, macLen int) (sk []byte, err error)

ECDH key agreement method used to establish secret keys for encryption.

type PublicKey

type PublicKey struct {
	X *big.Int
	Y *big.Int
	elliptic.Curve
	Params *ECIESParams
}

PublicKey is a representation of an elliptic curve public key.

func ImportECDSAPublic

func ImportECDSAPublic(pub *ecdsa.PublicKey) *PublicKey

Import an ECDSA public key as an ECIES public key.

func (*PublicKey) ExportECDSA

func (pub *PublicKey) ExportECDSA() *ecdsa.PublicKey

Export an ECIES public key as an ECDSA public key.