6dcefac868
With this commit a revocation message now carries 3 items: 1. A pre-image revoking the lowest unrevoked commitment transaction in the commitment chain. 2. A new key which extends the current revocation window by 1. This key is to be used for new commitment transactions. 3. A new hash which also extends the current revocation window by 1. This hash is to be used for new HTLC revocation hashes.
136 lines
4.5 KiB
Go
136 lines
4.5 KiB
Go
package lnwire
|
|
|
|
import (
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/roasbeef/btcd/btcec"
|
|
"github.com/roasbeef/btcd/wire"
|
|
)
|
|
|
|
// CommitRevocation is sent by either side once a CommitSignature message has
|
|
// been received, and validated. This message serves to revoke the prior
|
|
// commitment transaction, which was the most up to date version until a
|
|
// CommitSignature message referencing the specified ChannelPoint was received.
|
|
// Additionally, this message also piggyback's the next revocation hash that
|
|
// Alice should use when constructing the Bob's version of the next commitment
|
|
// transaction (which would be done before sending a CommitSignature message).
|
|
// This piggybacking allows Alice to send the next CommitSignature message
|
|
// modifying Bob's commitment transaction without first asking for a revocation
|
|
// hash initially.
|
|
// TODO(roasbeef): update docs everywhere
|
|
type CommitRevocation struct {
|
|
// ChannelPoint uniquely identifies to which currently active channel this
|
|
// CommitRevocation applies to.
|
|
ChannelPoint *wire.OutPoint
|
|
|
|
// Revocation is the pre-image to the revocation hash of the now prior
|
|
// commitment transaction.
|
|
//
|
|
// If the received revocation is the all zeroes hash ('0' * 32), then
|
|
// this CommitRevocation is being sent in order to build up the
|
|
// sender's initial revocation window (IRW). In this case, the
|
|
// CommitRevocation should be added to the receiver's queue of unused
|
|
// revocations to be used to construct future commitment transactions.
|
|
Revocation [32]byte
|
|
|
|
// NextRevocationKey is the next revocation key which should be added
|
|
// to the queue of unused revocation keys for the remote peer. This key
|
|
// will be used within the revocation clause for any new commitment
|
|
// transactions created for the remote peer.
|
|
NextRevocationKey *btcec.PublicKey
|
|
|
|
// NextRevocationHash is the next revocation hash which should be added
|
|
// to the queue on unused revocation hashes for the remote peer. This
|
|
// revocation hash will be used within any HTLC's included within this
|
|
// next commitment transaction.
|
|
NextRevocationHash [32]byte
|
|
}
|
|
|
|
// NewCommitRevocation creates a new CommitRevocation message.
|
|
func NewCommitRevocation() *CommitRevocation {
|
|
return &CommitRevocation{}
|
|
}
|
|
|
|
// A compile time check to ensure CommitRevocation implements the lnwire.Message
|
|
// interface.
|
|
var _ Message = (*CommitRevocation)(nil)
|
|
|
|
// Decode deserializes a serialized CommitRevocation message stored in the
|
|
// passed io.Reader observing the specified protocol version.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
func (c *CommitRevocation) Decode(r io.Reader, pver uint32) error {
|
|
// ChannelPoint (8)
|
|
// Revocation (32)
|
|
// NextRevocationKey (33)
|
|
// NextRevocationHash (32)
|
|
err := readElements(r,
|
|
&c.ChannelPoint,
|
|
&c.Revocation,
|
|
&c.NextRevocationKey,
|
|
&c.NextRevocationHash,
|
|
)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Encode serializes the target CommitRevocation into the passed io.Writer
|
|
// observing the protocol version specified.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
func (c *CommitRevocation) Encode(w io.Writer, pver uint32) error {
|
|
err := writeElements(w,
|
|
c.ChannelPoint,
|
|
c.Revocation,
|
|
c.NextRevocationKey,
|
|
c.NextRevocationHash,
|
|
)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Command returns the integer uniquely identifying this message type on the
|
|
// wire.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
func (c *CommitRevocation) Command() uint32 {
|
|
return CmdCommitRevocation
|
|
}
|
|
|
|
// MaxPayloadLength returns the maximum allowed payload size for a
|
|
// CommitRevocation complete message observing the specified protocol version.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
func (c *CommitRevocation) MaxPayloadLength(uint32) uint32 {
|
|
// 36 + 32 + 33 + 32
|
|
return 133
|
|
}
|
|
|
|
// Validate performs any necessary sanity checks to ensure all fields present
|
|
// on the CommitRevocation are valid.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
func (c *CommitRevocation) Validate() error {
|
|
// We're good!
|
|
return nil
|
|
}
|
|
|
|
// String returns the string representation of the target CommitRevocation.
|
|
//
|
|
// This is part of the lnwire.Message interface.
|
|
// TODO(roasbeef): remote all String() methods...spew should be used instead.
|
|
func (c *CommitRevocation) String() string {
|
|
return fmt.Sprintf("\n--- Begin CommitRevocation ---\n") +
|
|
fmt.Sprintf("ChannelPoint:\t%d\n", c.ChannelPoint) +
|
|
fmt.Sprintf("NextRevocationHash:\t%x\n", c.NextRevocationHash) +
|
|
fmt.Sprintf("Revocation:\t%x\n", c.Revocation) +
|
|
fmt.Sprintf("--- End CommitRevocation ---\n")
|
|
}
|