Go_I2p/lib/transport/ntcp/doc.md

ntcp

-- import "github.com/go-i2p/go-i2p/lib/transport/ntcp"

Usage

const (
	NOISE_DH_CURVE25519 = 1

	NOISE_CIPHER_CHACHAPOLY = 1
	NOISE_CIPHER_AESGCM     = 2

	NOISE_HASH_SHA256 = 3

	NOISE_PATTERN_XK = 11

	MaxPayloadSize = math.MaxUint16 - 16 - uint16Size /*data len*/
)

const (
	NTCP_PROTOCOL_VERSION = 2
	NTCP_PROTOCOL_NAME    = "NTCP2"
	NTCP_MESSAGE_MAX_SIZE = 65537
)

type NTCP2Session

type NTCP2Session struct {
	*noise.NoiseSession
	*NTCP2Transport
}

NTCP2Session extends the base noise.NoiseSession with NTCP2-specific functionality

func NewNTCP2Session

func NewNTCP2Session(noiseConfig router_info.RouterInfo) (*NTCP2Session, error)

NewNTCP2Session creates a new NTCP2 session using the existing noise implementation

func (*NTCP2Session) ComposeInitiatorHandshakeMessage

func (c *NTCP2Session) ComposeInitiatorHandshakeMessage(
	localStatic noise.DHKey,
	remoteStatic []byte,
	payload []byte,
	ephemeralPrivate []byte,
) (
	negotiationData,
	handshakeMessage []byte,
	handshakeState *noise.HandshakeState,
	err error,
)

Modify ComposeInitiatorHandshakeMessage in outgoing_handshake.go At the moment, remoteStatic is stored in the NTCP2Session() and doesn't need to be passed as an argument. You actually get it directly out of the remote RouterInfo, which the NoiseSession also has access to. So maybe, the interface should change so that we:

- A: get the localStatic out of the parent NTCP2Transport's routerInfo, which is the "local" routerInfo
- B: get the remoteStatic out of the NTCP2Session router, which is the "remote" routerInfo

func (*NTCP2Session) CreateSessionRequest

func (s *NTCP2Session) CreateSessionRequest() (*SessionRequest, error)

func (*NTCP2Session) DeobfuscateEphemeral

func (s *NTCP2Session) DeobfuscateEphemeral(obfuscatedEphemeralKey []byte) ([]byte, error)

DeobfuscateEphemeral reverses the key obfuscation

func (*NTCP2Session) ObfuscateEphemeral

func (s *NTCP2Session) ObfuscateEphemeral(ephemeralKey []byte) ([]byte, error)

ObfuscateEphemeral implements NTCP2's key obfuscation using AES-256-CBC

type NTCP2Transport

type NTCP2Transport struct {
	*noise.NoiseTransport
	*sntp.RouterTimestamper
}

NTCP2Transport is an ntcp2 transport implementing transport.NTCP2Transport interface

func NewNTCP2Transport

func NewNTCP2Transport(routerInfo *router_info.RouterInfo) (*NTCP2Transport, error)

func (*NTCP2Transport) Accept

func (t *NTCP2Transport) Accept() (net.Conn, error)

func (*NTCP2Transport) Address

func (t *NTCP2Transport) Address() (*router_address.RouterAddress, error)

func (*NTCP2Transport) Compatible

func (t *NTCP2Transport) Compatible(routerInfo router_info.RouterInfo) bool

func (*NTCP2Transport) GetSession

func (t *NTCP2Transport) GetSession(routerInfo router_info.RouterInfo) (transport.TransportSession, error)

func (*NTCP2Transport) Name

func (t *NTCP2Transport) Name() string

type PaddingStrategy

type PaddingStrategy interface {
	AddPadding(message []byte) []byte
	RemovePadding(message []byte) []byte
}

type SessionRequest

type SessionRequest struct {
	ObfuscatedKey []byte // 32 bytes
	Timestamp     uint32 // 4 bytes
	Padding       []byte // Random padding
}

ntcp

-- import "github.com/go-i2p/go-i2p/lib/transport/ntcp"

Usage

const (
	NOISE_DH_CURVE25519 = 1

	NOISE_CIPHER_CHACHAPOLY = 1
	NOISE_CIPHER_AESGCM     = 2

	NOISE_HASH_SHA256 = 3

	NOISE_PATTERN_XK = 11

	MaxPayloadSize = math.MaxUint16 - 16 - uint16Size /*data len*/
)

const (
	NTCP_PROTOCOL_VERSION = 2
	NTCP_PROTOCOL_NAME    = "NTCP2"
	NTCP_MESSAGE_MAX_SIZE = 65537
)

type NTCP2Session

type NTCP2Session struct {
	*noise.NoiseSession
	*NTCP2Transport
}

NTCP2Session extends the base noise.NoiseSession with NTCP2-specific functionality

func NewNTCP2Session

func NewNTCP2Session(noiseConfig router_info.RouterInfo) (*NTCP2Session, error)

NewNTCP2Session creates a new NTCP2 session using the existing noise implementation

func (*NTCP2Session) ComposeInitiatorHandshakeMessage

func (c *NTCP2Session) ComposeInitiatorHandshakeMessage(
	localStatic noise.DHKey,
	remoteStatic []byte,
	payload []byte,
	ephemeralPrivate []byte,
) (
	negotiationData,
	handshakeMessage []byte,
	handshakeState *noise.HandshakeState,
	err error,
)

Modify ComposeInitiatorHandshakeMessage in outgoing_handshake.go At the moment, remoteStatic is stored in the NTCP2Session() and doesn't need to be passed as an argument. You actually get it directly out of the remote RouterInfo, which the NoiseSession also has access to. So maybe, the interface should change so that we:

- A: get the localStatic out of the parent NTCP2Transport's routerInfo, which is the "local" routerInfo
- B: get the remoteStatic out of the NTCP2Session router, which is the "remote" routerInfo

func (*NTCP2Session) CreateSessionRequest

func (s *NTCP2Session) CreateSessionRequest() (*SessionRequest, error)

func (*NTCP2Session) DeobfuscateEphemeral

func (s *NTCP2Session) DeobfuscateEphemeral(obfuscatedEphemeralKey []byte) ([]byte, error)

DeobfuscateEphemeral reverses the key obfuscation

func (*NTCP2Session) ObfuscateEphemeral

func (s *NTCP2Session) ObfuscateEphemeral(ephemeralKey []byte) ([]byte, error)

ObfuscateEphemeral implements NTCP2's key obfuscation using AES-256-CBC

type NTCP2Transport

type NTCP2Transport struct {
	*noise.NoiseTransport
	*sntp.RouterTimestamper
}

NTCP2Transport is an ntcp2 transport implementing transport.NTCP2Transport interface

func NewNTCP2Transport

func NewNTCP2Transport(routerInfo *router_info.RouterInfo) (*NTCP2Transport, error)

func (*NTCP2Transport) Accept

func (t *NTCP2Transport) Accept() (net.Conn, error)

func (*NTCP2Transport) Address

func (t *NTCP2Transport) Address() (*router_address.RouterAddress, error)

func (*NTCP2Transport) Compatible

func (t *NTCP2Transport) Compatible(routerInfo router_info.RouterInfo) bool

func (*NTCP2Transport) GetSession

func (t *NTCP2Transport) GetSession(routerInfo router_info.RouterInfo) (transport.TransportSession, error)

func (*NTCP2Transport) Name

func (t *NTCP2Transport) Name() string

type PaddingStrategy

type PaddingStrategy interface {
	AddPadding(message []byte) []byte
	RemovePadding(message []byte) []byte
}

type SessionRequest

type SessionRequest struct {
	ObfuscatedKey []byte // 32 bytes
	Timestamp     uint32 // 4 bytes
	Padding       []byte // Random padding
}

ntcp

github.com/go-i2p/go-i2p/lib/transport/ntcp