lnd.xprv/lnwire/ping.go
Olaoluwa Osuntokun feec611531
lnwire+peer: implement new ping/pong messages and behavior
This commit implements the new ping/pong messages along with their new
behavior. The new set of ping/pong messages allow clients to generate
fake cover traffic as the ping messages tells the pong message how many
bytes to included and can also be padded itself.
2017-04-16 18:11:45 -07:00

76 lines
2.2 KiB
Go

package lnwire
import "io"
// PingPayload is a set of opaque bytes used to pad out a ping message.
type PingPayload []byte
// Ping defines a message which is sent by peers periodically to determine if
// the connection is still valid. Each ping message carries the number of bytes
// to pad the pong response with, and also a number of bytes to be ignored at
// the end of the ping message (which is padding).
type Ping struct {
// NumPongBytes is the number of bytes the pong response to this
// message should carry.
NumPongBytes uint16
// PaddingBytes is a set of opaque bytes used to pad out this ping
// message. Using this field in conjunction to the one above, it's
// possible for node to generate fake cover traffic.
PaddingBytes PingPayload
}
// NewPing returns a new Ping message.
func NewPing(numBytes uint16) *Ping {
return &Ping{
NumPongBytes: numBytes,
}
}
// A compile time check to ensure Ping implements the lnwire.Message interface.
var _ Message = (*Ping)(nil)
// Decode deserializes a serialized Ping message stored in the passed io.Reader
// observing the specified protocol version.
//
// This is part of the lnwire.Message interface.
func (p *Ping) Decode(r io.Reader, pver uint32) error {
return readElements(r,
&p.NumPongBytes,
&p.PaddingBytes)
}
// Encode serializes the target Ping into the passed io.Writer observing the
// protocol version specified.
//
// This is part of the lnwire.Message interface.
func (p *Ping) Encode(w io.Writer, pver uint32) error {
return writeElements(w,
p.NumPongBytes,
p.PaddingBytes)
}
// Command returns the integer uniquely identifying this message type on the
// wire.
//
// This is part of the lnwire.Message interface.
func (p *Ping) Command() uint32 {
return CmdPing
}
// MaxPayloadLength returns the maximum allowed payload size for a Ping
// complete message observing the specified protocol version.
//
// This is part of the lnwire.Message interface.
func (p Ping) MaxPayloadLength(uint32) uint32 {
return 65532
}
// Validate performs any necessary sanity checks to ensure all fields present
// on the Ping are valid.
//
// This is part of the lnwire.Message interface.
func (p *Ping) Validate() error {
return nil
}