Documentation
¶
Overview ¶
Package crypto provides core cryptographic functionality for the Reunion protocol.
Index ¶
- Constants
- Variables
- func DecodeT1Message(message []byte) ([]byte, []byte, []byte, error)
- func Exp(dst, x, y *[GroupElementLength]byte)
- func SPRPDecrypt(key *[SPRPKeyLength]byte, iv *[SPRPIVLength]byte, msg []byte) []byte
- func SPRPEncrypt(key *[SPRPKeyLength]byte, iv *[SPRPIVLength]byte, msg []byte) []byte
- type Keypair
- func (keypair *Keypair) Destroy()
- func (keypair *Keypair) HasElligator() bool
- func (keypair *Keypair) MarshalBinary() ([]byte, error)
- func (keypair *Keypair) Private() *PrivateKey
- func (keypair *Keypair) Public() *PublicKey
- func (keypair *Keypair) Representative() *Representative
- func (keypair *Keypair) UnmarshalBinary(data []byte) error
- type KeypairSerializable
- type PrivateKey
- func (k *PrivateKey) ByteArray32() *[32]byte
- func (k *PrivateKey) Bytes() []byte
- func (k *PrivateKey) Destroy()
- func (k *PrivateKey) Exp(sharedSecret *[GroupElementLength]byte, publicKey *PublicKey)
- func (k *PrivateKey) FromBytes(b []byte) error
- func (k *PrivateKey) Hex() string
- func (k *PrivateKey) MarshalBinary() ([]byte, error)
- func (k *PrivateKey) UnmarshalBinary(data []byte) error
- type PrivateKeyLengthError
- type PublicKey
- type PublicKeyLengthError
- type Representative
- type RepresentativeKeyLengthError
- type Session
- func (c *Session) ComposeType3Message(beta2 *PublicKey) ([]byte, error)
- func (c *Session) Destroy()
- func (c *Session) Epoch() uint64
- func (c *Session) GenerateType1Message(payload []byte) ([]byte, error)
- func (c *Session) GetCandidateKey(t2 []byte, alpha *PublicKey) ([]byte, error)
- func (c *Session) MarshalBinary() ([]byte, error)
- func (c *Session) ProcessType1MessageAlpha(alpha []byte) ([]byte, *PublicKey, error)
- func (c *Session) ProcessType3Message(t3, gamma []byte, beta2 *PublicKey) ([]byte, error)
- func (c *Session) SharedRandom() []byte
- func (c *Session) UnmarshalBinary(data []byte) error
Constants ¶
const ( // PayloadSize is the size of the Reunion protocol payload. PayloadSize = 1000 // SymmetricKeySize is the size of the symmetric keys we use. SymmetricKeySize = 32 // Type1MessageSize is the size in bytes of the Type 1 Message. Type1MessageSize = t1AlphaSize + t1BetaSize + t1GammaSize // Type2MessageSize is the size in bytes of the Type 2 Message. Type2MessageSize = SPRPMinimumBlockLength // Type3MessageSize is the size in bytes of the Type 3 Message. Type3MessageSize = SymmetricKeySize )
const ( // PublicKeyLength is the length of a Curve25519 public key. PublicKeyLength = 32 // RepresentativeLength is the length of an Elligator representative. RepresentativeLength = 32 // PrivateKeyLength is the length of a Curve25519 private key. PrivateKeyLength = 32 SharedSecretLength = 32 // GroupElementLength is the length of a ECDH group element in bytes. GroupElementLength = PublicKeyLength )
const ( // SPRPMinimumBlockLength is the minimum block length of the SPRP. SPRPMinimumBlockLength = 32 // SPRPKeyLength is the key size of the SPRP in bytes. SPRPKeyLength = 48 // SPRPIVLength is the IV size of the SPRP in bytes. SPRPIVLength = 16 )
const (
SharedEpochKeySize = 32
)
Variables ¶
var ErrInvalidMessageSize = errors.New("invalid message size")
ErrInvalidMessageSize is an error indicating an invalid message size.
var HashFunc = sha256.New
HashFunc implements the Hash interface as defined in https://godoc.org/hash#Hash We use it below in our HKDF construction.
Functions ¶
func DecodeT1Message ¶
DecodeT1Message upon success returns alpha, beta, gamma
func Exp ¶
func Exp(dst, x, y *[GroupElementLength]byte)
Exp sets the group element dst to be the result of x^y, over the ECDH group.
func SPRPDecrypt ¶
func SPRPDecrypt(key *[SPRPKeyLength]byte, iv *[SPRPIVLength]byte, msg []byte) []byte
SPRPDecrypt returns the plaintext of the message msg, decrypted via the Sphinx SPRP with the provided key and IV.
func SPRPEncrypt ¶
func SPRPEncrypt(key *[SPRPKeyLength]byte, iv *[SPRPIVLength]byte, msg []byte) []byte
SPRPEncrypt returns the ciphertext of the message msg, encrypted via the Sphinx SPRP with the provided key and IV.
Types ¶
type Keypair ¶
type Keypair struct {
// contains filtered or unexported fields
}
Keypair is a Curve25519 keypair with an optional Elligator representative. As only certain Curve25519 keys can be obfuscated with Elligator, the representative must be generated along with the keypair.
func NewKeypair ¶
NewKeypair generates a new Curve25519 keypair, and optionally also generates an Elligator representative of the public key.
func (*Keypair) Destroy ¶
func (keypair *Keypair) Destroy()
Destroy causes the private key meterial to be destroyed.
func (*Keypair) HasElligator ¶
HasElligator returns true if the Keypair has an Elligator representative.
func (*Keypair) MarshalBinary ¶
MarshalBinary is an implementation of a method on the BinaryMarshaler interface defined in https://golang.org/pkg/encoding/
func (*Keypair) Private ¶
func (keypair *Keypair) Private() *PrivateKey
Private returns the Curve25519 private key belonging to the Keypair.
func (*Keypair) Representative ¶
func (keypair *Keypair) Representative() *Representative
Representative returns the Elligator representative of the public key belonging to the Keypair.
func (*Keypair) UnmarshalBinary ¶
UnmarshalBinary is an implementation of a method on the BinaryUnmarshaler interface defined in https://golang.org/pkg/encoding/
type KeypairSerializable ¶
type KeypairSerializable struct {
Public *PublicKey
Private *PrivateKey
Representative *Representative
}
KeypairSerializable is used to help serialize Keypair.
type PrivateKey ¶
type PrivateKey struct {
// contains filtered or unexported fields
}
PrivateKey is a Curve25519 private key in little-endian byte order.
func NewEmptyPrivateKey ¶
func NewEmptyPrivateKey() *PrivateKey
NewEmptyPrivateKey creates a new PrivateKey with the lockedBuffer initialized to the correct size but not yet initialized to random bytes.
func NewRandomPrivateKey ¶
func NewRandomPrivateKey() *PrivateKey
NewRandomPrivateKey creates a new PrivateKey with the lockedBuffer initialized to PrivateKeyLength random bytes.
func (*PrivateKey) ByteArray32 ¶
func (k *PrivateKey) ByteArray32() *[32]byte
ByteArray32 returns a pointer to the raw Curve25519 private key.
func (*PrivateKey) Bytes ¶
func (k *PrivateKey) Bytes() []byte
Bytes returns a pointer to the raw Curve25519 private key.
func (*PrivateKey) Destroy ¶
func (k *PrivateKey) Destroy()
Destroy destroys the private key material and frees up the memory.
func (*PrivateKey) Exp ¶
func (k *PrivateKey) Exp(sharedSecret *[GroupElementLength]byte, publicKey *PublicKey)
Exp calculates the shared secret with the provided public key.
func (*PrivateKey) FromBytes ¶
func (k *PrivateKey) FromBytes(b []byte) error
FromBytes deserializes the byte slice b into the PrivateKey.
func (*PrivateKey) Hex ¶
func (k *PrivateKey) Hex() string
Hex returns the hexdecimal representation of the Curve25519 private key.
func (*PrivateKey) MarshalBinary ¶
func (k *PrivateKey) MarshalBinary() ([]byte, error)
MarshalBinary is an implementation of a method on the BinaryMarshaler interface defined in https://golang.org/pkg/encoding/
func (*PrivateKey) UnmarshalBinary ¶
func (k *PrivateKey) UnmarshalBinary(data []byte) error
UnmarshalBinary is an implementation of a method on the BinaryUnmarshaler interface defined in https://golang.org/pkg/encoding/
type PrivateKeyLengthError ¶
type PrivateKeyLengthError int
PrivateKeyLengthError is the error returned when the private key being imported is an invalid length.
func (PrivateKeyLengthError) Error ¶
func (e PrivateKeyLengthError) Error() string
type PublicKey ¶
type PublicKey [PublicKeyLength]byte
PublicKey is a Curve25519 public key in little-endian byte order.
func DecryptT1Beta ¶
DecryptT1Beta decrypts the Beta portion of a T1 message.
func NewPublicKey ¶
NewPublicKey creates a PublicKey from the raw bytes.
func PublicKeyFromHex ¶
PublicKeyFromHex returns a PublicKey from the hexdecimal representation.
func (*PublicKey) Bytes ¶
func (k *PublicKey) Bytes() *[PublicKeyLength]byte
Bytes returns a pointer to the raw Curve25519 public key.
func (*PublicKey) MarshalBinary ¶
MarshalBinary is an implementation of a method on the BinaryMarshaler interface defined in https://golang.org/pkg/encoding/
func (*PublicKey) UnmarshalBinary ¶
UnmarshalBinary is an implementation of a method on the BinaryUnmarshaler interface defined in https://golang.org/pkg/encoding/
type PublicKeyLengthError ¶
type PublicKeyLengthError int
PublicKeyLengthError is the error returned when the public key being imported is an invalid length.
func (PublicKeyLengthError) Error ¶
func (e PublicKeyLengthError) Error() string
type Representative ¶
type Representative [RepresentativeLength]byte
Representative is an Elligator representative of a Curve25519 public key in little-endian byte order.
func (*Representative) Bytes ¶
func (repr *Representative) Bytes() *[RepresentativeLength]byte
Bytes returns a pointer to the raw Elligator representative.
func (*Representative) FromBytes ¶
func (repr *Representative) FromBytes(b []byte) error
FromBytes deserializes the byte slice b into the PublicKey.
func (*Representative) MarshalBinary ¶
func (repr *Representative) MarshalBinary() ([]byte, error)
MarshalBinary is an implementation of a method on the BinaryMarshaler interface defined in https://golang.org/pkg/encoding/
func (*Representative) ToPublic ¶
func (repr *Representative) ToPublic() *PublicKey
ToPublic converts a Elligator representative to a Curve25519 public key.
func (*Representative) UnmarshalBinary ¶
func (repr *Representative) UnmarshalBinary(data []byte) error
UnmarshalBinary is an implementation of a method on the BinaryUnmarshaler interface defined in https://golang.org/pkg/encoding/
type RepresentativeKeyLengthError ¶
type RepresentativeKeyLengthError int
RepresentativeKeyLengthError is the error returned when the public key being imported is an invalid length.
func (RepresentativeKeyLengthError) Error ¶
func (e RepresentativeKeyLengthError) Error() string
type Session ¶
type Session struct {
// contains filtered or unexported fields
}
Session encapsulates all the key material and provides a few methods for performing core cryptographic operations that form the Reunion protocol. Note that this so called Session does NOT keep any state. Therefore these client methods are supplemented with some helper functions defined in crypto.go
func NewSession ¶
NewSession creates a new client given a shared passphrase, shared random value and an epoch number.
func NewSessionFromKey ¶
func NewSessionFromKey(sharedEpochKey *[SharedEpochKeySize]byte, sharedRandomValue []byte, epoch uint64) (*Session, error)
NewSessionFromKey creates a new client given a shared epoch key.
func (*Session) ComposeType3Message ¶
ComposeType3Message composes a type three message.
func (*Session) Destroy ¶
func (c *Session) Destroy()
Destroy destroys all the Session's key material and frees up the memory.
func (*Session) GenerateType1Message ¶
GenerateType1Message generates a Type 1 message.
func (*Session) GetCandidateKey ¶
GetCandidateKey extracts a candidate key from a type two message.
func (*Session) MarshalBinary ¶
Marshal serializes the client key material.
func (*Session) ProcessType1MessageAlpha ¶
ProcessType1MessageAlpha processes the alpha portion of a type one message.
func (*Session) ProcessType3Message ¶
ProcessType3Message processes a type three message.
func (*Session) SharedRandom ¶
SharedRandom returns the shared random value.
func (*Session) UnmarshalBinary ¶
Unmarshal deserializes the client key material.
Source Files