neo-go/pkg/neotest/signer.go
Dmitrii Stepanov 7b53a0c239 neotest: Add contract signer support
Signed-off-by: Dmitrii Stepanov <dima-stepan@yandex.ru>
2023-12-01 10:50:08 +03:00

260 lines
7.7 KiB
Go

package neotest
import (
"bytes"
"errors"
"fmt"
"sort"
"testing"
"github.com/nspcc-dev/neo-go/pkg/config/netmode"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/nspcc-dev/neo-go/pkg/wallet"
"github.com/stretchr/testify/require"
)
// Signer is a generic interface which can be either a simple- or multi-signature signer.
type Signer interface {
// Script returns a signer verification script.
Script() []byte
// ScriptHash returns a signer script hash.
ScriptHash() util.Uint160
// SignHashable returns an invocation script for signing an item.
SignHashable(uint32, hash.Hashable) []byte
// SignTx signs a transaction.
SignTx(netmode.Magic, *transaction.Transaction) error
}
// SingleSigner is a generic interface for a simple one-signature signer.
type SingleSigner interface {
Signer
// Account returns the underlying account which can be used to
// get a public key and/or sign arbitrary things.
Account() *wallet.Account
}
// MultiSigner is an interface for multisignature signing account.
type MultiSigner interface {
Signer
// Single returns a simple-signature signer for the n-th account in a list.
Single(n int) SingleSigner
}
// ContractSigner is an interface for contract signer.
type ContractSigner interface {
Signer
// InvocationScript returns an invocation script to be used as invocation script for contract-based witness.
InvocationScript(tx *transaction.Transaction) ([]byte, error)
}
// signer represents a simple-signature signer.
type signer wallet.Account
// multiSigner represents a single multi-signature signer consisting of the provided accounts.
type multiSigner struct {
accounts []*wallet.Account
m int
}
// NewSingleSigner creates a [SingleSigner] from the provided account. It has
// just one key, see [NewMultiSigner] for multisignature accounts.
func NewSingleSigner(acc *wallet.Account) SingleSigner {
if !vm.IsSignatureContract(acc.Contract.Script) {
panic("account must have simple-signature verification script")
}
return (*signer)(acc)
}
// Script implements Signer interface.
func (s *signer) Script() []byte {
return (*wallet.Account)(s).Contract.Script
}
// ScriptHash implements Signer interface.
func (s *signer) ScriptHash() util.Uint160 {
return (*wallet.Account)(s).Contract.ScriptHash()
}
// SignHashable implements Signer interface.
func (s *signer) SignHashable(magic uint32, item hash.Hashable) []byte {
return append([]byte{byte(opcode.PUSHDATA1), keys.SignatureLen},
(*wallet.Account)(s).SignHashable(netmode.Magic(magic), item)...)
}
// SignTx implements Signer interface.
func (s *signer) SignTx(magic netmode.Magic, tx *transaction.Transaction) error {
return (*wallet.Account)(s).SignTx(magic, tx)
}
// Account implements SingleSigner interface.
func (s *signer) Account() *wallet.Account {
return (*wallet.Account)(s)
}
// NewMultiSigner returns a multi-signature signer for the provided account.
// It must contain at least as many accounts as needed to sign the script.
func NewMultiSigner(accs ...*wallet.Account) MultiSigner {
if len(accs) == 0 {
panic("empty account list")
}
script := accs[0].Contract.Script
m, _, ok := vm.ParseMultiSigContract(script)
if !ok {
panic("all accounts must have multi-signature verification script")
}
if len(accs) < m {
panic(fmt.Sprintf("verification script requires %d signatures, "+
"but only %d accounts were provided", m, len(accs)))
}
sort.Slice(accs, func(i, j int) bool {
p1 := accs[i].PublicKey()
p2 := accs[j].PublicKey()
return p1.Cmp(p2) == -1
})
for _, acc := range accs {
if !bytes.Equal(script, acc.Contract.Script) {
panic("all accounts must have equal verification script")
}
}
return multiSigner{accounts: accs, m: m}
}
// ScriptHash implements Signer interface.
func (m multiSigner) ScriptHash() util.Uint160 {
return m.accounts[0].Contract.ScriptHash()
}
// Script implements Signer interface.
func (m multiSigner) Script() []byte {
return m.accounts[0].Contract.Script
}
// SignHashable implements Signer interface.
func (m multiSigner) SignHashable(magic uint32, item hash.Hashable) []byte {
var script []byte
for i := 0; i < m.m; i++ {
sign := m.accounts[i].SignHashable(netmode.Magic(magic), item)
script = append(script, byte(opcode.PUSHDATA1), keys.SignatureLen)
script = append(script, sign...)
}
return script
}
// SignTx implements Signer interface.
func (m multiSigner) SignTx(magic netmode.Magic, tx *transaction.Transaction) error {
invoc := m.SignHashable(uint32(magic), tx)
verif := m.Script()
for i := range tx.Scripts {
if bytes.Equal(tx.Scripts[i].VerificationScript, verif) {
tx.Scripts[i].InvocationScript = invoc
return nil
}
}
tx.Scripts = append(tx.Scripts, transaction.Witness{
InvocationScript: invoc,
VerificationScript: verif,
})
return nil
}
// Single implements MultiSigner interface.
func (m multiSigner) Single(n int) SingleSigner {
if len(m.accounts) <= n {
panic("invalid index")
}
return NewSingleSigner(wallet.NewAccountFromPrivateKey(m.accounts[n].PrivateKey()))
}
func checkMultiSigner(t testing.TB, s Signer) {
ms, ok := s.(multiSigner)
require.True(t, ok, "expected to be a multi-signer")
accs := ms.accounts
require.True(t, len(accs) > 0, "empty multi-signer")
m := len(accs[0].Contract.Parameters)
require.True(t, m <= len(accs), "honest not count is too big for a multi-signer")
h := accs[0].Contract.ScriptHash()
for i := 1; i < len(accs); i++ {
require.Equal(t, m, len(accs[i].Contract.Parameters), "inconsistent multi-signer accounts")
require.Equal(t, h, accs[i].Contract.ScriptHash(), "inconsistent multi-signer accounts")
}
}
type contractSigner struct {
params func(tx *transaction.Transaction) []any
scriptHash util.Uint160
}
// NewContractSigner returns a contract signer for the provided contract hash.
// getInvParams must return params to be used as invocation script for contract-based witness.
func NewContractSigner(h util.Uint160, getInvParams func(tx *transaction.Transaction) []any) ContractSigner {
return &contractSigner{
scriptHash: h,
params: getInvParams,
}
}
// InvocationScript implements ContractSigner.
func (s *contractSigner) InvocationScript(tx *transaction.Transaction) ([]byte, error) {
params := s.params(tx)
script := io.NewBufBinWriter()
for i := range params {
emit.Any(script.BinWriter, params[i])
}
if script.Err != nil {
return nil, script.Err
}
return script.Bytes(), nil
}
// Script implements ContractSigner.
func (s *contractSigner) Script() []byte {
return []byte{}
}
// ScriptHash implements ContractSigner.
func (s *contractSigner) ScriptHash() util.Uint160 {
return s.scriptHash
}
// SignHashable implements ContractSigner.
func (s *contractSigner) SignHashable(uint32, hash.Hashable) []byte {
panic("not supported")
}
// SignTx implements ContractSigner.
func (s *contractSigner) SignTx(magic netmode.Magic, tx *transaction.Transaction) error {
pos := -1
for idx := range tx.Signers {
if tx.Signers[idx].Account.Equals(s.ScriptHash()) {
pos = idx
break
}
}
if pos < 0 {
return fmt.Errorf("signer %s not found", s.ScriptHash().String())
}
if len(tx.Scripts) < pos {
return errors.New("transaction is not yet signed by the previous signer")
}
invoc, err := s.InvocationScript(tx)
if err != nil {
return err
}
if len(tx.Scripts) == pos {
tx.Scripts = append(tx.Scripts, transaction.Witness{})
}
tx.Scripts[pos].InvocationScript = invoc
tx.Scripts[pos].VerificationScript = s.Script()
return nil
}