package ethchain
import (
"github.com/ethereum/eth-go/ethutil"
"github.com/obscuren/secp256k1-go"
"math/big"
)
var ContractAddr = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
type Transaction struct {
Nonce uint64
Recipient []byte
Value *big.Int
Gas *big.Int
GasPrice *big.Int
Data []byte
Init []byte
v byte
r, s []byte
// Indicates whether this tx is a contract creation transaction
contractCreation bool
}
func NewContractCreationTx(value, gas, gasPrice *big.Int, script []byte, init []byte) *Transaction {
return &Transaction{Value: value, Gas: gas, GasPrice: gasPrice, Data: script, Init: init, contractCreation: true}
}
func NewTransactionMessage(to []byte, value, gas, gasPrice *big.Int, data []byte) *Transaction {
return &Transaction{Recipient: to, Value: value, GasPrice: gasPrice, Gas: gas, Data: data}
}
func NewTransactionFromBytes(data []byte) *Transaction {
tx := &Transaction{}
tx.RlpDecode(data)
return tx
}
func NewTransactionFromValue(val *ethutil.Value) *Transaction {
tx := &Transaction{}
tx.RlpValueDecode(val)
return tx
}
func (tx *Transaction) Hash() []byte {
data := []interface{}{tx.Nonce, tx.Value, tx.GasPrice, tx.Gas, tx.Recipient, tx.Data}
if tx.contractCreation {
data = append(data, tx.Init)
}
return ethutil.Sha3Bin(ethutil.NewValue(data).Encode())
}
func (tx *Transaction) IsContract() bool {
return tx.contractCreation
}
func (tx *Transaction) CreationAddress() []byte {
return ethutil.Sha3Bin(ethutil.NewValue([]interface{}{tx.Sender(), tx.Nonce}).Encode())[12:]
}
func (tx *Transaction) Signature(key []byte) []byte {
hash := tx.Hash()
sig, _ := secp256k1.Sign(hash, key)
return sig
}
func (tx *Transaction) PublicKey() []byte {
hash := tx.Hash()
// If we don't make a copy we will overwrite the existing underlying array
dst := make([]byte, len(tx.r))
copy(dst, tx.r)
sig := append(dst, tx.s...)
sig = append(sig, tx.v-27)
pubkey, _ := secp256k1.RecoverPubkey(hash, sig)
return pubkey
}
func (tx *Transaction) Sender() []byte {
pubkey := tx.PublicKey()
// Validate the returned key.
// Return nil if public key isn't in full format
if pubkey[0] != 4 {
return nil
}
return ethutil.Sha3Bin(pubkey[1:])[12:]
}
func (tx *Transaction) Sign(privk []byte) error {
sig := tx.Signature(privk)
tx.r = sig[:32]
tx.s = sig[32:64]
tx.v = sig[64] + 27
return nil
}
// [ NONCE, VALUE, GASPRICE, GAS, TO, DATA, V, R, S ]
// [ NONCE, VALUE, GASPRICE, GAS, 0, CODE, INIT, V, R, S ]
func (tx *Transaction) RlpData() interface{} {
data := []interface{}{tx.Nonce, tx.Value, tx.GasPrice, tx.Gas, tx.Recipient, tx.Data}
if tx.contractCreation {
data = append(data, tx.Init)
}
return append(data, tx.v, tx.r, tx.s)
}
func (tx *Transaction) RlpValue() *ethutil.Value {
return ethutil.NewValue(tx.RlpData())
}
func (tx *Transaction) RlpEncode() []byte {
return tx.RlpValue().Encode()
}
func (tx *Transaction) RlpDecode(data []byte) {
tx.RlpValueDecode(ethutil.NewValueFromBytes(data))
}
func (tx *Transaction) RlpValueDecode(decoder *ethutil.Value) {
tx.Nonce = decoder.Get(0).Uint()
tx.Value = decoder.Get(1).BigInt()
tx.GasPrice = decoder.Get(2).BigInt()
tx.Gas = decoder.Get(3).BigInt()
tx.Recipient = decoder.Get(4).Bytes()
tx.Data = decoder.Get(5).Bytes()
// If the list is of length 10 it's a contract creation tx
if decoder.Len() == 10 {
tx.contractCreation = true
tx.Init = decoder.Get(6).Bytes()
tx.v = byte(decoder.Get(7).Uint())
tx.r = decoder.Get(8).Bytes()
tx.s = decoder.Get(9).Bytes()
} else {
tx.v = byte(decoder.Get(6).Uint())
tx.r = decoder.Get(7).Bytes()
tx.s = decoder.Get(8).Bytes()
}
}
