lbcutil/psbt/partial_output.go
2021-09-10 16:37:45 -04:00

139 lines
2.9 KiB
Go

package psbt
import (
"bytes"
"io"
"sort"
"github.com/lbryio/lbcd/wire"
)
// POutput is a struct encapsulating all the data that can be attached
// to any specific output of the PSBT.
type POutput struct {
RedeemScript []byte
WitnessScript []byte
Bip32Derivation []*Bip32Derivation
}
// NewPsbtOutput creates an instance of PsbtOutput; the three parameters
// redeemScript, witnessScript and Bip32Derivation are all allowed to be
// `nil`.
func NewPsbtOutput(redeemScript []byte, witnessScript []byte,
bip32Derivation []*Bip32Derivation) *POutput {
return &POutput{
RedeemScript: redeemScript,
WitnessScript: witnessScript,
Bip32Derivation: bip32Derivation,
}
}
// deserialize attempts to recode a new POutput from the passed io.Reader.
func (po *POutput) deserialize(r io.Reader) error {
for {
keyint, keydata, err := getKey(r)
if err != nil {
return err
}
if keyint == -1 {
// Reached separator byte
break
}
value, err := wire.ReadVarBytes(
r, 0, MaxPsbtValueLength, "PSBT value",
)
if err != nil {
return err
}
switch OutputType(keyint) {
case RedeemScriptOutputType:
if po.RedeemScript != nil {
return ErrDuplicateKey
}
if keydata != nil {
return ErrInvalidKeydata
}
po.RedeemScript = value
case WitnessScriptOutputType:
if po.WitnessScript != nil {
return ErrDuplicateKey
}
if keydata != nil {
return ErrInvalidKeydata
}
po.WitnessScript = value
case Bip32DerivationOutputType:
if !validatePubkey(keydata) {
return ErrInvalidKeydata
}
master, derivationPath, err := readBip32Derivation(value)
if err != nil {
return err
}
// Duplicate keys are not allowed
for _, x := range po.Bip32Derivation {
if bytes.Equal(x.PubKey, keydata) {
return ErrDuplicateKey
}
}
po.Bip32Derivation = append(po.Bip32Derivation,
&Bip32Derivation{
PubKey: keydata,
MasterKeyFingerprint: master,
Bip32Path: derivationPath,
},
)
default:
// Unknown type is allowed for inputs but not outputs.
return ErrInvalidPsbtFormat
}
}
return nil
}
// serialize attempts to write out the target POutput into the passed
// io.Writer.
func (po *POutput) serialize(w io.Writer) error {
if po.RedeemScript != nil {
err := serializeKVPairWithType(
w, uint8(RedeemScriptOutputType), nil, po.RedeemScript,
)
if err != nil {
return err
}
}
if po.WitnessScript != nil {
err := serializeKVPairWithType(
w, uint8(WitnessScriptOutputType), nil, po.WitnessScript,
)
if err != nil {
return err
}
}
sort.Sort(Bip32Sorter(po.Bip32Derivation))
for _, kd := range po.Bip32Derivation {
err := serializeKVPairWithType(w,
uint8(Bip32DerivationOutputType),
kd.PubKey,
SerializeBIP32Derivation(
kd.MasterKeyFingerprint,
kd.Bip32Path,
),
)
if err != nil {
return err
}
}
return nil
}