lnd.xprv/lnwire/commit_signature.go
2016-01-16 17:14:35 -08:00

126 lines
3.0 KiB
Go

package lnwire
import (
"fmt"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcutil"
"io"
)
// Multiple Clearing Requests are possible by putting this inside an array of
// clearing requests
type CommitSignature struct {
// We can use a different data type for this if necessary...
ChannelID uint64
// Height of the commitment
// You should have the most recent commitment height stored locally
// This should be validated!
// This is used for shachain.
// Each party increments their own CommitmentHeight, they can differ for
// each part of the Commitment.
CommitmentHeight uint64
// List of HTLC Keys which are updated from all parties
UpdatedHTLCKeys []uint64
// Hash of the revocation to use
RevocationHash [20]byte
// Total miners' fee that was used
Fee btcutil.Amount
// Signature for the new Commitment
CommitSig *btcec.Signature // Requester's Commitment
}
func (c *CommitSignature) Decode(r io.Reader, pver uint32) error {
// ChannelID(8)
// CommitmentHeight(8)
// c.UpdatedHTLCKeys(8*1000max)
// RevocationHash(20)
// Fee(8)
// RequesterCommitSig(73max+2)
err := readElements(r,
&c.ChannelID,
&c.CommitmentHeight,
&c.UpdatedHTLCKeys,
&c.RevocationHash,
&c.Fee,
&c.CommitSig,
)
if err != nil {
return err
}
return nil
}
// Creates a new CommitSignature
func NewCommitSignature() *CommitSignature {
return &CommitSignature{}
}
// Serializes the item from the CommitSignature struct
// Writes the data to w
func (c *CommitSignature) Encode(w io.Writer, pver uint32) error {
err := writeElements(w,
c.ChannelID,
c.CommitmentHeight,
c.UpdatedHTLCKeys,
c.RevocationHash,
c.Fee,
c.CommitSig,
)
if err != nil {
return err
}
return nil
}
func (c *CommitSignature) Command() uint32 {
return CmdCommitSignature
}
func (c *CommitSignature) MaxPayloadLength(uint32) uint32 {
return 8192
}
// Makes sure the struct data is valid (e.g. no negatives or invalid pkscripts)
func (c *CommitSignature) Validate() error {
if c.Fee < 0 {
// While fees can be negative, it's too confusing to allow
// negative payments. Maybe for some wallets, but not this one!
return fmt.Errorf("Amount paid cannot be negative.")
}
// We're good!
return nil
}
func (c *CommitSignature) String() string {
// c.ChannelID,
// c.CommitmentHeight,
// c.RevocationHash,
// c.UpdatedHTLCKeys,
// c.Fee,
// c.CommitSig,
var serializedSig []byte
if &c.CommitSig != nil && c.CommitSig.R != nil {
serializedSig = c.CommitSig.Serialize()
}
var items string
for i := 0; i < len(c.UpdatedHTLCKeys); i++ {
items += fmt.Sprintf("%d ", c.UpdatedHTLCKeys[i])
}
return fmt.Sprintf("\n--- Begin CommitSignature ---\n") +
fmt.Sprintf("ChannelID:\t\t%d\n", c.ChannelID) +
fmt.Sprintf("CommitmentHeight:\t%d\n", c.CommitmentHeight) +
fmt.Sprintf("UpdatedHTLCKeys:\t%s\n", items) +
fmt.Sprintf("RevocationHash:\t\t%x\n", c.RevocationHash) +
fmt.Sprintf("Fee:\t\t\t%s\n", c.Fee.String()) +
fmt.Sprintf("CommitSig:\t\t%x\n", serializedSig) +
fmt.Sprintf("--- End CommitSignature ---\n")
}