736 lines
16 KiB
Go
736 lines
16 KiB
Go
package lnwire
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import (
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"bytes"
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"encoding/binary"
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"fmt"
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"image/color"
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"io"
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"math"
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"net"
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"github.com/go-errors/errors"
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"github.com/roasbeef/btcd/btcec"
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"github.com/roasbeef/btcd/chaincfg/chainhash"
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"github.com/roasbeef/btcd/wire"
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"github.com/roasbeef/btcutil"
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)
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// MaxSliceLength is the maximum allowed length for any opaque byte slices in
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// the wire protocol.
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const MaxSliceLength = 65535
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// PkScript is simple type definition which represents a raw serialized public
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// key script.
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type PkScript []byte
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// addressType specifies the network protocol and version that should be used
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// when connecting to a node at a particular address.
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type addressType uint8
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const (
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// noAddr denotes a blank address. An address of this type indicates
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// that a node doesn't have any advertise d addresses.
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noAddr addressType = 0
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// tcp4Addr denotes an IPv4 TCP address.
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tcp4Addr addressType = 1
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// tcp4Addr denotes an IPv6 TCP address.
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tcp6Addr addressType = 2
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// v2OnionAddr denotes a version 2 Tor onion service address.
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v2OnionAddr addressType = 3
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// v3OnionAddr denotes a version 3 Tor (prop224) onion service
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// addresses
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v3OnionAddr addressType = 4
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)
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// AddrLen returns the number of bytes that it takes to encode the target
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// address.
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func (a addressType) AddrLen() uint16 {
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switch a {
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case noAddr:
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return 0
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case tcp4Addr:
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return 6
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case tcp6Addr:
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return 18
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case v2OnionAddr:
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return 12
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case v3OnionAddr:
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return 37
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default:
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return 0
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}
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}
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// writeElement is a one-stop shop to write the big endian representation of
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// any element which is to be serialized for the wire protocol. The passed
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// io.Writer should be backed by an appropriately sized byte slice, or be able
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// to dynamically expand to accommodate additional data.
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//
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// TODO(roasbeef): this should eventually draw from a buffer pool for
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// serialization.
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// TODO(roasbeef): switch to var-ints for all?
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func writeElement(w io.Writer, element interface{}) error {
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switch e := element.(type) {
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case uint8:
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var b [1]byte
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b[0] = e
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case FundingFlag:
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var b [1]byte
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b[0] = uint8(e)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case uint16:
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var b [2]byte
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binary.BigEndian.PutUint16(b[:], e)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case ChanUpdateFlag:
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var b [2]byte
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binary.BigEndian.PutUint16(b[:], uint16(e))
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case ErrorCode:
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var b [2]byte
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binary.BigEndian.PutUint16(b[:], uint16(e))
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case MilliSatoshi:
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var b [8]byte
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binary.BigEndian.PutUint64(b[:], uint64(e))
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case btcutil.Amount:
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var b [8]byte
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binary.BigEndian.PutUint64(b[:], uint64(e))
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case uint32:
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var b [4]byte
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binary.BigEndian.PutUint32(b[:], e)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case uint64:
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var b [8]byte
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binary.BigEndian.PutUint64(b[:], e)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case *btcec.PublicKey:
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if e == nil {
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return fmt.Errorf("cannot write nil pubkey")
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}
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var b [33]byte
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serializedPubkey := e.SerializeCompressed()
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copy(b[:], serializedPubkey)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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case []*btcec.Signature:
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var b [2]byte
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numSigs := uint16(len(e))
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binary.BigEndian.PutUint16(b[:], numSigs)
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if _, err := w.Write(b[:]); err != nil {
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return err
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}
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for _, sig := range e {
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if err := writeElement(w, sig); err != nil {
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return err
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}
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}
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case *btcec.Signature:
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if e == nil {
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return fmt.Errorf("cannot write nil signature")
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}
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var b [64]byte
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err := SerializeSigToWire(&b, e)
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if err != nil {
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return err
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}
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// Write buffer
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if _, err = w.Write(b[:]); err != nil {
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return err
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}
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case PingPayload:
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var l [2]byte
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binary.BigEndian.PutUint16(l[:], uint16(len(e)))
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if _, err := w.Write(l[:]); err != nil {
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return err
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}
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case PongPayload:
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var l [2]byte
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binary.BigEndian.PutUint16(l[:], uint16(len(e)))
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if _, err := w.Write(l[:]); err != nil {
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return err
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}
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case ErrorData:
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var l [2]byte
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binary.BigEndian.PutUint16(l[:], uint16(len(e)))
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if _, err := w.Write(l[:]); err != nil {
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return err
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}
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case OpaqueReason:
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var l [2]byte
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binary.BigEndian.PutUint16(l[:], uint16(len(e)))
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if _, err := w.Write(l[:]); err != nil {
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return err
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}
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case []byte:
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case PkScript:
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// The largest script we'll accept is a p2wsh which is exactly
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// 34 bytes long.
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scriptLength := len(e)
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if scriptLength > 34 {
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return fmt.Errorf("'PkScript' too long")
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}
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if err := wire.WriteVarBytes(w, 0, e); err != nil {
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return err
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}
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case *RawFeatureVector:
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if e == nil {
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return fmt.Errorf("cannot write nil feature vector")
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}
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if err := e.Encode(w); err != nil {
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return err
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}
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case wire.OutPoint:
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var h [32]byte
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copy(h[:], e.Hash[:])
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if _, err := w.Write(h[:]); err != nil {
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return err
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}
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if e.Index > math.MaxUint16 {
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return fmt.Errorf("index for outpoint (%v) is "+
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"greater than max index of %v", e.Index,
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math.MaxUint16)
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}
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var idx [2]byte
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binary.BigEndian.PutUint16(idx[:], uint16(e.Index))
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if _, err := w.Write(idx[:]); err != nil {
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return err
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}
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case ChannelID:
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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case FailCode:
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if err := writeElement(w, uint16(e)); err != nil {
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return err
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}
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case ShortChannelID:
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// Check that field fit in 3 bytes and write the blockHeight
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if e.BlockHeight > ((1 << 24) - 1) {
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return errors.New("block height should fit in 3 bytes")
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}
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var blockHeight [4]byte
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binary.BigEndian.PutUint32(blockHeight[:], e.BlockHeight)
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if _, err := w.Write(blockHeight[1:]); err != nil {
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return err
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}
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// Check that field fit in 3 bytes and write the txIndex
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if e.TxIndex > ((1 << 24) - 1) {
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return errors.New("tx index should fit in 3 bytes")
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}
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var txIndex [4]byte
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binary.BigEndian.PutUint32(txIndex[:], e.TxIndex)
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if _, err := w.Write(txIndex[1:]); err != nil {
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return err
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}
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// Write the txPosition
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var txPosition [2]byte
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binary.BigEndian.PutUint16(txPosition[:], e.TxPosition)
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if _, err := w.Write(txPosition[:]); err != nil {
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return err
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}
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case *net.TCPAddr:
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if e == nil {
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return fmt.Errorf("cannot write nil TCPAddr")
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}
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// TODO(roasbeef): account for onion types too
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if e.IP.To4() != nil {
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var descriptor [1]byte
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descriptor[0] = uint8(tcp4Addr)
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if _, err := w.Write(descriptor[:]); err != nil {
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return err
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}
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var ip [4]byte
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copy(ip[:], e.IP.To4())
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if _, err := w.Write(ip[:]); err != nil {
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return err
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}
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} else {
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var descriptor [1]byte
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descriptor[0] = uint8(tcp6Addr)
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if _, err := w.Write(descriptor[:]); err != nil {
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return err
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}
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var ip [16]byte
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copy(ip[:], e.IP.To16())
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if _, err := w.Write(ip[:]); err != nil {
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return err
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}
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}
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var port [2]byte
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binary.BigEndian.PutUint16(port[:], uint16(e.Port))
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if _, err := w.Write(port[:]); err != nil {
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return err
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}
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case []net.Addr:
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// First, we'll encode all the addresses into an intermediate
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// buffer. We need to do this in order to compute the total
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// length of the addresses.
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var addrBuf bytes.Buffer
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for _, address := range e {
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if err := writeElement(&addrBuf, address); err != nil {
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return err
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}
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}
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|
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// With the addresses fully encoded, we can now write out the
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// number of bytes needed to encode them.
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addrLen := addrBuf.Len()
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if err := writeElement(w, uint16(addrLen)); err != nil {
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return err
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}
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|
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// Finally, we'll write out the raw addresses themselves, but
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// only if we have any bytes to write.
|
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if addrLen > 0 {
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if _, err := w.Write(addrBuf.Bytes()); err != nil {
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return err
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}
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}
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case color.RGBA:
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if err := writeElements(w, e.R, e.G, e.B); err != nil {
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return err
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}
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|
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case DeliveryAddress:
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var length [2]byte
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binary.BigEndian.PutUint16(length[:], uint16(len(e)))
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if _, err := w.Write(length[:]); err != nil {
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return err
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}
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if _, err := w.Write(e[:]); err != nil {
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return err
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}
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default:
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return fmt.Errorf("Unknown type in writeElement: %T", e)
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}
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|
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return nil
|
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}
|
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|
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// writeElements is writes each element in the elements slice to the passed
|
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// io.Writer using writeElement.
|
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func writeElements(w io.Writer, elements ...interface{}) error {
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for _, element := range elements {
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err := writeElement(w, element)
|
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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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|
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// readElement is a one-stop utility function to deserialize any datastructure
|
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// encoded using the serialization format of lnwire.
|
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func readElement(r io.Reader, element interface{}) error {
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var err error
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switch e := element.(type) {
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case *uint8:
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var b [1]uint8
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if _, err := r.Read(b[:]); err != nil {
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return err
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}
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*e = b[0]
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case *FundingFlag:
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var b [1]uint8
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if _, err := r.Read(b[:]); err != nil {
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return err
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}
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*e = FundingFlag(b[0])
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case *uint16:
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var b [2]byte
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if _, err := io.ReadFull(r, b[:]); err != nil {
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return err
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}
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*e = binary.BigEndian.Uint16(b[:])
|
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case *ChanUpdateFlag:
|
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var b [2]byte
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if _, err := io.ReadFull(r, b[:]); err != nil {
|
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return err
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}
|
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*e = ChanUpdateFlag(binary.BigEndian.Uint16(b[:]))
|
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case *ErrorCode:
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var b [2]byte
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if _, err := io.ReadFull(r, b[:]); err != nil {
|
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return err
|
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}
|
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*e = ErrorCode(binary.BigEndian.Uint16(b[:]))
|
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case *uint32:
|
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var b [4]byte
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if _, err := io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
|
}
|
|
*e = binary.BigEndian.Uint32(b[:])
|
|
case *uint64:
|
|
var b [8]byte
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if _, err := io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
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}
|
|
*e = binary.BigEndian.Uint64(b[:])
|
|
case *MilliSatoshi:
|
|
var b [8]byte
|
|
if _, err := io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
|
}
|
|
*e = MilliSatoshi(int64(binary.BigEndian.Uint64(b[:])))
|
|
case *btcutil.Amount:
|
|
var b [8]byte
|
|
if _, err := io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
|
}
|
|
*e = btcutil.Amount(int64(binary.BigEndian.Uint64(b[:])))
|
|
case **btcec.PublicKey:
|
|
var b [btcec.PubKeyBytesLenCompressed]byte
|
|
if _, err = io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
pubKey, err := btcec.ParsePubKey(b[:], btcec.S256())
|
|
if err != nil {
|
|
return err
|
|
}
|
|
*e = pubKey
|
|
case **RawFeatureVector:
|
|
f := NewRawFeatureVector()
|
|
err = f.Decode(r)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
*e = f
|
|
|
|
case *[]*btcec.Signature:
|
|
var l [2]byte
|
|
if _, err := io.ReadFull(r, l[:]); err != nil {
|
|
return err
|
|
}
|
|
numSigs := binary.BigEndian.Uint16(l[:])
|
|
|
|
var sigs []*btcec.Signature
|
|
if numSigs > 0 {
|
|
sigs = make([]*btcec.Signature, numSigs)
|
|
for i := 0; i < int(numSigs); i++ {
|
|
if err := readElement(r, &sigs[i]); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
}
|
|
|
|
*e = sigs
|
|
|
|
case **btcec.Signature:
|
|
var b [64]byte
|
|
if _, err := io.ReadFull(r, b[:]); err != nil {
|
|
return err
|
|
}
|
|
err = DeserializeSigFromWire(e, b)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
case *OpaqueReason:
|
|
var l [2]byte
|
|
if _, err := io.ReadFull(r, l[:]); err != nil {
|
|
return err
|
|
}
|
|
reasonLen := binary.BigEndian.Uint16(l[:])
|
|
|
|
*e = OpaqueReason(make([]byte, reasonLen))
|
|
if _, err := io.ReadFull(r, *e); err != nil {
|
|
return err
|
|
}
|
|
case *ErrorData:
|
|
var l [2]byte
|
|
if _, err := io.ReadFull(r, l[:]); err != nil {
|
|
return err
|
|
}
|
|
errorLen := binary.BigEndian.Uint16(l[:])
|
|
|
|
*e = ErrorData(make([]byte, errorLen))
|
|
if _, err := io.ReadFull(r, *e); err != nil {
|
|
return err
|
|
}
|
|
case *PingPayload:
|
|
var l [2]byte
|
|
if _, err := io.ReadFull(r, l[:]); err != nil {
|
|
return err
|
|
}
|
|
pingLen := binary.BigEndian.Uint16(l[:])
|
|
|
|
*e = PingPayload(make([]byte, pingLen))
|
|
if _, err := io.ReadFull(r, *e); err != nil {
|
|
return err
|
|
}
|
|
case *PongPayload:
|
|
var l [2]byte
|
|
if _, err := io.ReadFull(r, l[:]); err != nil {
|
|
return err
|
|
}
|
|
pongLen := binary.BigEndian.Uint16(l[:])
|
|
|
|
*e = PongPayload(make([]byte, pongLen))
|
|
if _, err := io.ReadFull(r, *e); err != nil {
|
|
return err
|
|
}
|
|
case []byte:
|
|
if _, err := io.ReadFull(r, e); err != nil {
|
|
return err
|
|
}
|
|
case *PkScript:
|
|
pkScript, err := wire.ReadVarBytes(r, 0, 34, "pkscript")
|
|
if err != nil {
|
|
return err
|
|
}
|
|
*e = pkScript
|
|
case *wire.OutPoint:
|
|
var h [32]byte
|
|
if _, err = io.ReadFull(r, h[:]); err != nil {
|
|
return err
|
|
}
|
|
hash, err := chainhash.NewHash(h[:])
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
var idxBytes [2]byte
|
|
_, err = io.ReadFull(r, idxBytes[:])
|
|
if err != nil {
|
|
return err
|
|
}
|
|
index := binary.BigEndian.Uint16(idxBytes[:])
|
|
|
|
*e = wire.OutPoint{
|
|
Hash: *hash,
|
|
Index: uint32(index),
|
|
}
|
|
case *FailCode:
|
|
if err := readElement(r, (*uint16)(e)); err != nil {
|
|
return err
|
|
}
|
|
case *ChannelID:
|
|
if _, err := io.ReadFull(r, e[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
case *ShortChannelID:
|
|
var blockHeight [4]byte
|
|
if _, err = io.ReadFull(r, blockHeight[1:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
var txIndex [4]byte
|
|
if _, err = io.ReadFull(r, txIndex[1:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
var txPosition [2]byte
|
|
if _, err = io.ReadFull(r, txPosition[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
*e = ShortChannelID{
|
|
BlockHeight: binary.BigEndian.Uint32(blockHeight[:]),
|
|
TxIndex: binary.BigEndian.Uint32(txIndex[:]),
|
|
TxPosition: binary.BigEndian.Uint16(txPosition[:]),
|
|
}
|
|
|
|
case *[]net.Addr:
|
|
// First, we'll read the number of total bytes that have been
|
|
// used to encode the set of addresses.
|
|
var numAddrsBytes [2]byte
|
|
if _, err = io.ReadFull(r, numAddrsBytes[:]); err != nil {
|
|
return err
|
|
}
|
|
addrsLen := binary.BigEndian.Uint16(numAddrsBytes[:])
|
|
|
|
// With the number of addresses, read, we'll now pull in the
|
|
// buffer of the encoded addresses into memory.
|
|
addrs := make([]byte, addrsLen)
|
|
if _, err := io.ReadFull(r, addrs[:]); err != nil {
|
|
return err
|
|
}
|
|
addrBuf := bytes.NewReader(addrs)
|
|
|
|
// Finally, we'll parse the remaining address payload in
|
|
// series, using the first byte to denote how to decode the
|
|
// address itself.
|
|
var (
|
|
addresses []net.Addr
|
|
addrBytesRead uint16
|
|
)
|
|
for addrBytesRead < addrsLen {
|
|
var descriptor [1]byte
|
|
if _, err = io.ReadFull(addrBuf, descriptor[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
addrBytesRead++
|
|
|
|
address := &net.TCPAddr{}
|
|
aType := addressType(descriptor[0])
|
|
switch aType {
|
|
|
|
case noAddr:
|
|
addrBytesRead += aType.AddrLen()
|
|
continue
|
|
|
|
case tcp4Addr:
|
|
var ip [4]byte
|
|
if _, err = io.ReadFull(addrBuf, ip[:]); err != nil {
|
|
return err
|
|
}
|
|
address.IP = (net.IP)(ip[:])
|
|
|
|
var port [2]byte
|
|
if _, err = io.ReadFull(addrBuf, port[:]); err != nil {
|
|
return err
|
|
}
|
|
|
|
address.Port = int(binary.BigEndian.Uint16(port[:]))
|
|
|
|
addrBytesRead += aType.AddrLen()
|
|
|
|
case tcp6Addr:
|
|
var ip [16]byte
|
|
if _, err = io.ReadFull(addrBuf, ip[:]); err != nil {
|
|
return err
|
|
}
|
|
address.IP = (net.IP)(ip[:])
|
|
|
|
var port [2]byte
|
|
if _, err = io.ReadFull(addrBuf, port[:]); err != nil {
|
|
return err
|
|
}
|
|
address.Port = int(binary.BigEndian.Uint16(port[:]))
|
|
|
|
addrBytesRead += aType.AddrLen()
|
|
|
|
case v2OnionAddr:
|
|
addrBytesRead += aType.AddrLen()
|
|
continue
|
|
|
|
case v3OnionAddr:
|
|
addrBytesRead += aType.AddrLen()
|
|
continue
|
|
|
|
default:
|
|
return fmt.Errorf("unknown address type: %v", aType)
|
|
}
|
|
|
|
addresses = append(addresses, address)
|
|
}
|
|
|
|
*e = addresses
|
|
case *color.RGBA:
|
|
err := readElements(r,
|
|
&e.R,
|
|
&e.G,
|
|
&e.B,
|
|
)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
case *DeliveryAddress:
|
|
var addrLen [2]byte
|
|
if _, err = io.ReadFull(r, addrLen[:]); err != nil {
|
|
return err
|
|
}
|
|
length := binary.BigEndian.Uint16(addrLen[:])
|
|
|
|
var addrBytes [34]byte
|
|
if length > 34 {
|
|
return fmt.Errorf("Cannot read %d bytes into addrBytes", length)
|
|
}
|
|
if _, err = io.ReadFull(r, addrBytes[:length]); err != nil {
|
|
return err
|
|
}
|
|
*e = addrBytes[:length]
|
|
default:
|
|
return fmt.Errorf("Unknown type in readElement: %T", e)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// readElements deserializes a variable number of elements into the passed
|
|
// io.Reader, with each element being deserialized according to the readElement
|
|
// function.
|
|
func readElements(r io.Reader, elements ...interface{}) error {
|
|
for _, element := range elements {
|
|
err := readElement(r, element)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return nil
|
|
}
|