mirror of
https://github.com/lightningnetwork/lnd.git
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watchtower/blob: move code to justice_kit_packet.go
In preparation for the next commit which will introduce the `JusticeKit` interface, here we just move the code related to building the actual justice kit packet into a separate file.
This commit is contained in:
Elle Mouton
parent
204ca6cb0f
commit
048dc54110
@ -1,98 +1,12 @@
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package blob
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import (
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"bytes"
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"crypto/rand"
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"encoding/binary"
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"errors"
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"fmt"
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"io"
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"github.com/btcsuite/btcd/btcec/v2"
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"github.com/btcsuite/btcd/txscript"
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"github.com/lightningnetwork/lnd/input"
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"github.com/lightningnetwork/lnd/lnwire"
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"golang.org/x/crypto/chacha20poly1305"
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)
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const (
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// NonceSize is the length of a chacha20poly1305 nonce, 24 bytes.
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NonceSize = chacha20poly1305.NonceSizeX
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// KeySize is the length of a chacha20poly1305 key, 32 bytes.
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KeySize = chacha20poly1305.KeySize
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// CiphertextExpansion is the number of bytes padded to a plaintext
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// encrypted with chacha20poly1305, which comes from a 16-byte MAC.
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CiphertextExpansion = 16
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// V0PlaintextSize is the plaintext size of a version 0 encoded blob.
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// sweep address length: 1 byte
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// padded sweep address: 42 bytes
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// revocation pubkey: 33 bytes
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// local delay pubkey: 33 bytes
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// csv delay: 4 bytes
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// commit to-local revocation sig: 64 bytes
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// commit to-remote pubkey: 33 bytes, maybe blank
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// commit to-remote sig: 64 bytes, maybe blank
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V0PlaintextSize = 274
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// MaxSweepAddrSize defines the maximum sweep address size that can be
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// encoded in a blob.
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MaxSweepAddrSize = 42
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)
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// Size returns the size of the encoded-and-encrypted blob in bytes.
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//
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// nonce: 24 bytes
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// enciphered plaintext: n bytes
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// MAC: 16 bytes
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func Size(blobType Type) int {
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return NonceSize + PlaintextSize(blobType) + CiphertextExpansion
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}
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// PlaintextSize returns the size of the encoded-but-unencrypted blob in bytes.
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func PlaintextSize(blobType Type) int {
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switch {
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case blobType.Has(FlagCommitOutputs):
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return V0PlaintextSize
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default:
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return 0
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}
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}
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var (
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// byteOrder specifies a big-endian encoding of all integer values.
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byteOrder = binary.BigEndian
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// ErrUnknownBlobType signals that we don't understand the requested
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// blob encoding scheme.
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ErrUnknownBlobType = errors.New("unknown blob type")
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// ErrCiphertextTooSmall is a decryption error signaling that the
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// ciphertext is smaller than the ciphertext expansion factor.
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ErrCiphertextTooSmall = errors.New(
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"ciphertext is too small for chacha20poly1305",
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)
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// ErrNoCommitToRemoteOutput is returned when trying to retrieve the
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// commit to-remote output from the blob, though none exists.
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ErrNoCommitToRemoteOutput = errors.New(
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"cannot obtain commit to-remote p2wkh output script from blob",
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)
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// ErrSweepAddressToLong is returned when trying to encode or decode a
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// sweep address with length greater than the maximum length of 42
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// bytes, which supports p2wkh and p2sh addresses.
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ErrSweepAddressToLong = fmt.Errorf(
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"sweep address must be less than or equal to %d bytes long",
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MaxSweepAddrSize,
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)
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)
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// PubKey is a 33-byte, serialized compressed public key.
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type PubKey [33]byte
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// JusticeKit is lé Blob of Justice. The JusticeKit contains information
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// required to construct a justice transaction, that sweeps a remote party's
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// revoked commitment transaction. It supports encryption and decryption using
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@ -136,17 +50,18 @@ type JusticeKit struct {
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// SIGHASH_ALL.
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CommitToLocalSig lnwire.Sig
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// CommitToRemotePubKey is the public key in the to-remote output of the revoked
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// commitment transaction.
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// CommitToRemotePubKey is the public key in the to-remote output of the
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// revoked commitment transaction.
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//
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// NOTE: This value is only used if it contains a valid compressed
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// public key.
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CommitToRemotePubKey PubKey
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// CommitToRemoteSig is a signature under CommitToRemotePubKey using SIGHASH_ALL.
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// CommitToRemoteSig is a signature under CommitToRemotePubKey using
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// SIGHASH_ALL.
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//
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// NOTE: This value is only used if CommitToRemotePubKey contains a valid
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// compressed public key.
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// NOTE: This value is only used if CommitToRemotePubKey contains a
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// valid compressed public key.
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CommitToRemoteSig lnwire.Sig
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}
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@ -236,281 +151,3 @@ func (b *JusticeKit) CommitToRemoteWitnessStack() ([][]byte, error) {
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return witnessStack, nil
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}
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// Encrypt encodes the blob of justice using encoding version, and then
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// creates a ciphertext using chacha20poly1305 under the chosen (nonce, key)
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// pair.
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//
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// NOTE: It is the caller's responsibility to ensure that this method is only
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// called once for a given (nonce, key) pair.
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func (b *JusticeKit) Encrypt(key BreachKey) ([]byte, error) {
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// Encode the plaintext using the provided version, to obtain the
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// plaintext bytes.
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var ptxtBuf bytes.Buffer
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err := b.encode(&ptxtBuf, b.BlobType)
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if err != nil {
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return nil, err
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}
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// Create a new chacha20poly1305 cipher, using a 32-byte key.
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cipher, err := chacha20poly1305.NewX(key[:])
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if err != nil {
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return nil, err
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}
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// Allocate the ciphertext, which will contain the nonce, encrypted
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// plaintext and MAC.
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plaintext := ptxtBuf.Bytes()
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ciphertext := make([]byte, Size(b.BlobType))
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// Generate a random 24-byte nonce in the ciphertext's prefix.
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nonce := ciphertext[:NonceSize]
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if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
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return nil, err
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}
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// Finally, encrypt the plaintext using the given nonce, storing the
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// result in the ciphertext buffer.
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cipher.Seal(ciphertext[NonceSize:NonceSize], nonce, plaintext, nil)
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return ciphertext, nil
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}
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// Decrypt unenciphers a blob of justice by decrypting the ciphertext using
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// chacha20poly1305 with the chosen (nonce, key) pair. The internal plaintext is
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// then deserialized using the given encoding version.
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func Decrypt(key BreachKey, ciphertext []byte,
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blobType Type) (*JusticeKit, error) {
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// Fail if the blob's overall length is less than required for the nonce
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// and expansion factor.
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if len(ciphertext) < NonceSize+CiphertextExpansion {
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return nil, ErrCiphertextTooSmall
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}
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// Create a new chacha20poly1305 cipher, using a 32-byte key.
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cipher, err := chacha20poly1305.NewX(key[:])
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if err != nil {
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return nil, err
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}
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// Allocate the final buffer that will contain the blob's plaintext
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// bytes, which is computed by subtracting the ciphertext expansion
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// factor from the blob's length.
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plaintext := make([]byte, len(ciphertext)-CiphertextExpansion)
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// Decrypt the ciphertext, placing the resulting plaintext in our
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// plaintext buffer.
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nonce := ciphertext[:NonceSize]
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_, err = cipher.Open(plaintext[:0], nonce, ciphertext[NonceSize:], nil)
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if err != nil {
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return nil, err
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}
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// If decryption succeeded, we will then decode the plaintext bytes
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// using the specified blob version.
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boj := &JusticeKit{
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BlobType: blobType,
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}
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err = boj.decode(bytes.NewReader(plaintext), blobType)
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if err != nil {
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return nil, err
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}
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return boj, nil
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}
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// encode serializes the JusticeKit according to the version, returning an
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// error if the version is unknown.
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func (b *JusticeKit) encode(w io.Writer, blobType Type) error {
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switch {
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case blobType.Has(FlagCommitOutputs):
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return b.encodeV0(w)
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default:
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return ErrUnknownBlobType
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}
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}
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// decode deserializes the JusticeKit according to the version, returning an
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// error if the version is unknown.
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func (b *JusticeKit) decode(r io.Reader, blobType Type) error {
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switch {
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case blobType.Has(FlagCommitOutputs):
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return b.decodeV0(r)
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default:
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return ErrUnknownBlobType
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}
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}
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// encodeV0 encodes the JusticeKit using the version 0 encoding scheme to the
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// provided io.Writer. The encoding supports sweeping of the commit to-local
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// output, and optionally the commit to-remote output. The encoding produces a
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// constant-size plaintext size of 274 bytes.
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//
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// blob version 0 plaintext encoding:
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//
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// sweep address length: 1 byte
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// padded sweep address: 42 bytes
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// revocation pubkey: 33 bytes
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// local delay pubkey: 33 bytes
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// csv delay: 4 bytes
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// commit to-local revocation sig: 64 bytes
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// commit to-remote pubkey: 33 bytes, maybe blank
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// commit to-remote sig: 64 bytes, maybe blank
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func (b *JusticeKit) encodeV0(w io.Writer) error {
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// Assert the sweep address length is sane.
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if len(b.SweepAddress) > MaxSweepAddrSize {
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return ErrSweepAddressToLong
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}
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// Write the actual length of the sweep address as a single byte.
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err := binary.Write(w, byteOrder, uint8(len(b.SweepAddress)))
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if err != nil {
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return err
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}
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// Pad the sweep address to our maximum length of 42 bytes.
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var sweepAddressBuf [MaxSweepAddrSize]byte
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copy(sweepAddressBuf[:], b.SweepAddress)
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// Write padded 42-byte sweep address.
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_, err = w.Write(sweepAddressBuf[:])
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if err != nil {
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return err
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}
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// Write 33-byte revocation public key.
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_, err = w.Write(b.RevocationPubKey[:])
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if err != nil {
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return err
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}
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// Write 33-byte local delay public key.
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_, err = w.Write(b.LocalDelayPubKey[:])
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if err != nil {
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return err
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}
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// Write 4-byte CSV delay.
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err = binary.Write(w, byteOrder, b.CSVDelay)
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if err != nil {
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return err
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}
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// Write 64-byte revocation signature for commit to-local output.
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_, err = w.Write(b.CommitToLocalSig.RawBytes())
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if err != nil {
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return err
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}
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// Write 33-byte commit to-remote public key, which may be blank.
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_, err = w.Write(b.CommitToRemotePubKey[:])
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if err != nil {
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return err
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}
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// Write 64-byte commit to-remote signature, which may be blank.
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_, err = w.Write(b.CommitToRemoteSig.RawBytes())
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return err
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}
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// decodeV0 reconstructs a JusticeKit from the io.Reader, using version 0
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// encoding scheme. This will parse a constant size input stream of 274 bytes to
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// recover information for the commit to-local output, and possibly the commit
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// to-remote output.
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//
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// blob version 0 plaintext encoding:
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//
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// sweep address length: 1 byte
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// padded sweep address: 42 bytes
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// revocation pubkey: 33 bytes
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// local delay pubkey: 33 bytes
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// csv delay: 4 bytes
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// commit to-local revocation sig: 64 bytes
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// commit to-remote pubkey: 33 bytes, maybe blank
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// commit to-remote sig: 64 bytes, maybe blank
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func (b *JusticeKit) decodeV0(r io.Reader) error {
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// Read the sweep address length as a single byte.
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var sweepAddrLen uint8
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err := binary.Read(r, byteOrder, &sweepAddrLen)
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if err != nil {
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return err
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}
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// Assert the sweep address length is sane.
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if sweepAddrLen > MaxSweepAddrSize {
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return ErrSweepAddressToLong
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}
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// Read padded 42-byte sweep address.
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var sweepAddressBuf [MaxSweepAddrSize]byte
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_, err = io.ReadFull(r, sweepAddressBuf[:])
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if err != nil {
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return err
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}
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// Parse sweep address from padded buffer.
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b.SweepAddress = make([]byte, sweepAddrLen)
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copy(b.SweepAddress, sweepAddressBuf[:])
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// Read 33-byte revocation public key.
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_, err = io.ReadFull(r, b.RevocationPubKey[:])
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if err != nil {
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return err
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}
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// Read 33-byte local delay public key.
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_, err = io.ReadFull(r, b.LocalDelayPubKey[:])
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if err != nil {
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return err
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}
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// Read 4-byte CSV delay.
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err = binary.Read(r, byteOrder, &b.CSVDelay)
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if err != nil {
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return err
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}
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// Read 64-byte revocation signature for commit to-local output.
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var localSig [64]byte
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_, err = io.ReadFull(r, localSig[:])
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if err != nil {
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return err
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}
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b.CommitToLocalSig, err = lnwire.NewSigFromWireECDSA(localSig[:])
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if err != nil {
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return err
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}
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var (
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commitToRemotePubkey PubKey
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commitToRemoteSig [64]byte
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)
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// Read 33-byte commit to-remote public key, which may be discarded.
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_, err = io.ReadFull(r, commitToRemotePubkey[:])
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if err != nil {
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return err
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}
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// Read 64-byte commit to-remote signature, which may be discarded.
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_, err = io.ReadFull(r, commitToRemoteSig[:])
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if err != nil {
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return err
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}
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// Only populate the commit to-remote fields in the decoded blob if a
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// valid compressed public key was read from the reader.
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if btcec.IsCompressedPubKey(commitToRemotePubkey[:]) {
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b.CommitToRemotePubKey = commitToRemotePubkey
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b.CommitToRemoteSig, err = lnwire.NewSigFromWireECDSA(
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commitToRemoteSig[:],
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)
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if err != nil {
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return err
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}
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}
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return nil
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}
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371
watchtower/blob/justice_kit_packet.go
Normal file
371
watchtower/blob/justice_kit_packet.go
Normal file
@ -0,0 +1,371 @@
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package blob
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import (
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"bytes"
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"crypto/rand"
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"encoding/binary"
|
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"errors"
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"fmt"
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"io"
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"github.com/btcsuite/btcd/btcec/v2"
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"github.com/lightningnetwork/lnd/lnwire"
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"golang.org/x/crypto/chacha20poly1305"
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)
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const (
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// NonceSize is the length of a chacha20poly1305 nonce, 24 bytes.
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NonceSize = chacha20poly1305.NonceSizeX
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// KeySize is the length of a chacha20poly1305 key, 32 bytes.
|
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KeySize = chacha20poly1305.KeySize
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|
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// CiphertextExpansion is the number of bytes padded to a plaintext
|
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// encrypted with chacha20poly1305, which comes from a 16-byte MAC.
|
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CiphertextExpansion = 16
|
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|
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// V0PlaintextSize is the plaintext size of a version 0 encoded blob.
|
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// sweep address length: 1 byte
|
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// padded sweep address: 42 bytes
|
||||
// revocation pubkey: 33 bytes
|
||||
// local delay pubkey: 33 bytes
|
||||
// csv delay: 4 bytes
|
||||
// commit to-local revocation sig: 64 bytes
|
||||
// commit to-remote pubkey: 33 bytes, maybe blank
|
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// commit to-remote sig: 64 bytes, maybe blank
|
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V0PlaintextSize = 274
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|
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// MaxSweepAddrSize defines the maximum sweep address size that can be
|
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// encoded in a blob.
|
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MaxSweepAddrSize = 42
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)
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|
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var (
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// byteOrder specifies a big-endian encoding of all integer values.
|
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byteOrder = binary.BigEndian
|
||||
|
||||
// ErrUnknownBlobType signals that we don't understand the requested
|
||||
// blob encoding scheme.
|
||||
ErrUnknownBlobType = errors.New("unknown blob type")
|
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|
||||
// ErrCiphertextTooSmall is a decryption error signaling that the
|
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// ciphertext is smaller than the ciphertext expansion factor.
|
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ErrCiphertextTooSmall = errors.New(
|
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"ciphertext is too small for chacha20poly1305",
|
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)
|
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|
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// ErrNoCommitToRemoteOutput is returned when trying to retrieve the
|
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// commit to-remote output from the blob, though none exists.
|
||||
ErrNoCommitToRemoteOutput = errors.New(
|
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"cannot obtain commit to-remote p2wkh output script from blob",
|
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)
|
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|
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// ErrSweepAddressToLong is returned when trying to encode or decode a
|
||||
// sweep address with length greater than the maximum length of 42
|
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// bytes, which supports p2wkh and p2sh addresses.
|
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ErrSweepAddressToLong = fmt.Errorf(
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"sweep address must be less than or equal to %d bytes long",
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MaxSweepAddrSize,
|
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)
|
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)
|
||||
|
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// Size returns the size of the encoded-and-encrypted blob in bytes.
|
||||
//
|
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// nonce: 24 bytes
|
||||
// enciphered plaintext: n bytes
|
||||
// MAC: 16 bytes
|
||||
func Size(blobType Type) int {
|
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return NonceSize + PlaintextSize(blobType) + CiphertextExpansion
|
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}
|
||||
|
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// PlaintextSize returns the size of the encoded-but-unencrypted blob in bytes.
|
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func PlaintextSize(blobType Type) int {
|
||||
switch {
|
||||
case blobType.Has(FlagCommitOutputs):
|
||||
return V0PlaintextSize
|
||||
default:
|
||||
return 0
|
||||
}
|
||||
}
|
||||
|
||||
// PubKey is a 33-byte, serialized compressed public key.
|
||||
type PubKey [33]byte
|
||||
|
||||
// Encrypt encodes the blob of justice using encoding version, and then
|
||||
// creates a ciphertext using chacha20poly1305 under the chosen (nonce, key)
|
||||
// pair.
|
||||
//
|
||||
// NOTE: It is the caller's responsibility to ensure that this method is only
|
||||
// called once for a given (nonce, key) pair.
|
||||
func (b *JusticeKit) Encrypt(key BreachKey) ([]byte, error) {
|
||||
// Encode the plaintext using the provided version, to obtain the
|
||||
// plaintext bytes.
|
||||
var ptxtBuf bytes.Buffer
|
||||
err := b.encode(&ptxtBuf, b.BlobType)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Create a new chacha20poly1305 cipher, using a 32-byte key.
|
||||
cipher, err := chacha20poly1305.NewX(key[:])
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Allocate the ciphertext, which will contain the nonce, encrypted
|
||||
// plaintext and MAC.
|
||||
plaintext := ptxtBuf.Bytes()
|
||||
ciphertext := make([]byte, Size(b.BlobType))
|
||||
|
||||
// Generate a random 24-byte nonce in the ciphertext's prefix.
|
||||
nonce := ciphertext[:NonceSize]
|
||||
if _, err := io.ReadFull(rand.Reader, nonce); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Finally, encrypt the plaintext using the given nonce, storing the
|
||||
// result in the ciphertext buffer.
|
||||
cipher.Seal(ciphertext[NonceSize:NonceSize], nonce, plaintext, nil)
|
||||
|
||||
return ciphertext, nil
|
||||
}
|
||||
|
||||
// Decrypt unenciphers a blob of justice by decrypting the ciphertext using
|
||||
// chacha20poly1305 with the chosen (nonce, key) pair. The internal plaintext is
|
||||
// then deserialized using the given encoding version.
|
||||
func Decrypt(key BreachKey, ciphertext []byte,
|
||||
blobType Type) (*JusticeKit, error) {
|
||||
|
||||
// Fail if the blob's overall length is less than required for the nonce
|
||||
// and expansion factor.
|
||||
if len(ciphertext) < NonceSize+CiphertextExpansion {
|
||||
return nil, ErrCiphertextTooSmall
|
||||
}
|
||||
|
||||
// Create a new chacha20poly1305 cipher, using a 32-byte key.
|
||||
cipher, err := chacha20poly1305.NewX(key[:])
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// Allocate the final buffer that will contain the blob's plaintext
|
||||
// bytes, which is computed by subtracting the ciphertext expansion
|
||||
// factor from the blob's length.
|
||||
plaintext := make([]byte, len(ciphertext)-CiphertextExpansion)
|
||||
|
||||
// Decrypt the ciphertext, placing the resulting plaintext in our
|
||||
// plaintext buffer.
|
||||
nonce := ciphertext[:NonceSize]
|
||||
_, err = cipher.Open(plaintext[:0], nonce, ciphertext[NonceSize:], nil)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
// If decryption succeeded, we will then decode the plaintext bytes
|
||||
// using the specified blob version.
|
||||
boj := &JusticeKit{
|
||||
BlobType: blobType,
|
||||
}
|
||||
err = boj.decode(bytes.NewReader(plaintext), blobType)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return boj, nil
|
||||
}
|
||||
|
||||
// encode serializes the JusticeKit according to the version, returning an
|
||||
// error if the version is unknown.
|
||||
func (b *JusticeKit) encode(w io.Writer, blobType Type) error {
|
||||
switch {
|
||||
case blobType.Has(FlagCommitOutputs):
|
||||
return b.encodeV0(w)
|
||||
default:
|
||||
return ErrUnknownBlobType
|
||||
}
|
||||
}
|
||||
|
||||
// decode deserializes the JusticeKit according to the version, returning an
|
||||
// error if the version is unknown.
|
||||
func (b *JusticeKit) decode(r io.Reader, blobType Type) error {
|
||||
switch {
|
||||
case blobType.Has(FlagCommitOutputs):
|
||||
return b.decodeV0(r)
|
||||
default:
|
||||
return ErrUnknownBlobType
|
||||
}
|
||||
}
|
||||
|
||||
// encodeV0 encodes the JusticeKit using the version 0 encoding scheme to the
|
||||
// provided io.Writer. The encoding supports sweeping of the commit to-local
|
||||
// output, and optionally the commit to-remote output. The encoding produces a
|
||||
// constant-size plaintext size of 274 bytes.
|
||||
//
|
||||
// blob version 0 plaintext encoding:
|
||||
//
|
||||
// sweep address length: 1 byte
|
||||
// padded sweep address: 42 bytes
|
||||
// revocation pubkey: 33 bytes
|
||||
// local delay pubkey: 33 bytes
|
||||
// csv delay: 4 bytes
|
||||
// commit to-local revocation sig: 64 bytes
|
||||
// commit to-remote pubkey: 33 bytes, maybe blank
|
||||
// commit to-remote sig: 64 bytes, maybe blank
|
||||
func (b *JusticeKit) encodeV0(w io.Writer) error {
|
||||
// Assert the sweep address length is sane.
|
||||
if len(b.SweepAddress) > MaxSweepAddrSize {
|
||||
return ErrSweepAddressToLong
|
||||
}
|
||||
|
||||
// Write the actual length of the sweep address as a single byte.
|
||||
err := binary.Write(w, byteOrder, uint8(len(b.SweepAddress)))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Pad the sweep address to our maximum length of 42 bytes.
|
||||
var sweepAddressBuf [MaxSweepAddrSize]byte
|
||||
copy(sweepAddressBuf[:], b.SweepAddress)
|
||||
|
||||
// Write padded 42-byte sweep address.
|
||||
_, err = w.Write(sweepAddressBuf[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 33-byte revocation public key.
|
||||
_, err = w.Write(b.RevocationPubKey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 33-byte local delay public key.
|
||||
_, err = w.Write(b.LocalDelayPubKey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 4-byte CSV delay.
|
||||
err = binary.Write(w, byteOrder, b.CSVDelay)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 64-byte revocation signature for commit to-local output.
|
||||
_, err = w.Write(b.CommitToLocalSig.RawBytes())
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 33-byte commit to-remote public key, which may be blank.
|
||||
_, err = w.Write(b.CommitToRemotePubKey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Write 64-byte commit to-remote signature, which may be blank.
|
||||
_, err = w.Write(b.CommitToRemoteSig.RawBytes())
|
||||
|
||||
return err
|
||||
}
|
||||
|
||||
// decodeV0 reconstructs a JusticeKit from the io.Reader, using version 0
|
||||
// encoding scheme. This will parse a constant size input stream of 274 bytes to
|
||||
// recover information for the commit to-local output, and possibly the commit
|
||||
// to-remote output.
|
||||
//
|
||||
// blob version 0 plaintext encoding:
|
||||
//
|
||||
// sweep address length: 1 byte
|
||||
// padded sweep address: 42 bytes
|
||||
// revocation pubkey: 33 bytes
|
||||
// local delay pubkey: 33 bytes
|
||||
// csv delay: 4 bytes
|
||||
// commit to-local revocation sig: 64 bytes
|
||||
// commit to-remote pubkey: 33 bytes, maybe blank
|
||||
// commit to-remote sig: 64 bytes, maybe blank
|
||||
func (b *JusticeKit) decodeV0(r io.Reader) error {
|
||||
// Read the sweep address length as a single byte.
|
||||
var sweepAddrLen uint8
|
||||
err := binary.Read(r, byteOrder, &sweepAddrLen)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Assert the sweep address length is sane.
|
||||
if sweepAddrLen > MaxSweepAddrSize {
|
||||
return ErrSweepAddressToLong
|
||||
}
|
||||
|
||||
// Read padded 42-byte sweep address.
|
||||
var sweepAddressBuf [MaxSweepAddrSize]byte
|
||||
_, err = io.ReadFull(r, sweepAddressBuf[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Parse sweep address from padded buffer.
|
||||
b.SweepAddress = make([]byte, sweepAddrLen)
|
||||
copy(b.SweepAddress, sweepAddressBuf[:])
|
||||
|
||||
// Read 33-byte revocation public key.
|
||||
_, err = io.ReadFull(r, b.RevocationPubKey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Read 33-byte local delay public key.
|
||||
_, err = io.ReadFull(r, b.LocalDelayPubKey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Read 4-byte CSV delay.
|
||||
err = binary.Read(r, byteOrder, &b.CSVDelay)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Read 64-byte revocation signature for commit to-local output.
|
||||
var localSig [64]byte
|
||||
_, err = io.ReadFull(r, localSig[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
b.CommitToLocalSig, err = lnwire.NewSigFromWireECDSA(localSig[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
var (
|
||||
commitToRemotePubkey PubKey
|
||||
commitToRemoteSig [64]byte
|
||||
)
|
||||
|
||||
// Read 33-byte commit to-remote public key, which may be discarded.
|
||||
_, err = io.ReadFull(r, commitToRemotePubkey[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Read 64-byte commit to-remote signature, which may be discarded.
|
||||
_, err = io.ReadFull(r, commitToRemoteSig[:])
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// Only populate the commit to-remote fields in the decoded blob if a
|
||||
// valid compressed public key was read from the reader.
|
||||
if btcec.IsCompressedPubKey(commitToRemotePubkey[:]) {
|
||||
b.CommitToRemotePubKey = commitToRemotePubkey
|
||||
b.CommitToRemoteSig, err = lnwire.NewSigFromWireECDSA(
|
||||
commitToRemoteSig[:],
|
||||
)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user