def refund(self, contract):
fundtx = self.find_transaction_to_address(contract.p2sh)
print("Fund tx found in refund: ", fundtx)
refundPubKey = self.find_refundAddr(contract)
print('refundPubKey: {0}'.format(refundPubKey))
redeemScript = CScript(x(contract.redeemScript))
txin = CMutableTxIn(fundtx['outpoint'])
txout = CMutableTxOut(fundtx['amount'] - FEE,
refundPubKey.to_scriptPubKey())
# Create the unsigned raw transaction.
tx = CMutableTransaction([txin], [txout])
# Set nSequence and nLockTime
txin.nSequence = 0
tx.nLockTime = contract.redeemblocknum
# Create the unsigned raw transaction.
sighash = SignatureHash(redeemScript, tx, 0, SIGHASH_ALL)
privkey = self.zcashd.dumpprivkey(refundPubKey)
sig = privkey.sign(sighash) + bytes([SIGHASH_ALL])
# Sign without secret
txin.scriptSig = CScript([sig, privkey.pub, OP_FALSE, redeemScript])
txin_scriptPubKey = redeemScript.to_p2sh_scriptPubKey()
print('Raw redeem transaction hex: {0}'.format(b2x(tx.serialize())))
res = VerifyScript(txin.scriptSig, txin_scriptPubKey, tx, 0,
(SCRIPT_VERIFY_P2SH, ))
print("Script verified, sending raw transaction... (NOT)", res)
txid = self.zcashd.sendrawtransaction(tx)
refund_tx = b2x(lx(b2x(txid)))
fund_tx = str(fundtx['outpoint'])
return {"refund_tx": refund_tx, "fund_tx": fund_tx}
def redeem_after_timelock(contract):
print(contract)
p2sh = contract.p2sh
fundtx = find_transaction_to_address(p2sh)
amount = fundtx['amount'] / COIN
if (fundtx['address'].__str__() != p2sh):
print("no fund transaction found to the contract p2sh address ", p2sh)
quit()
# print("Found fundtx:", fundtx)
# Parsing redeemblocknum from the redeemscript of the p2sh
redeemblocknum = find_redeemblocknum(contract)
blockcount = zcashd.getblockcount()
print("Current block:", blockcount, "Can redeem from block:",
redeemblocknum)
if (still_locked(contract)):
print("too early for redeeming with timelock try again at block",
redeemblocknum, "or later")
return
print("Found {0} in p2sh {1}, redeeming...".format(amount, p2sh))
redeemPubKey = find_refundAddr(contract)
print('refundPubKey', redeemPubKey)
redeemScript = CScript(x(contract.redeemScript))
txin = CMutableTxIn(fundtx['outpoint'])
txout = CMutableTxOut(fundtx['amount'] - FEE,
redeemPubKey.to_scriptPubKey())
# Create the unsigned raw transaction.
txin.nSequence = 0
tx = CMutableTransaction([txin], [txout])
tx.nLockTime = redeemblocknum
sighash = SignatureHash(redeemScript, tx, 0, SIGHASH_ALL)
# TODO: figure out how to better protect privkey
privkey = zcashd.dumpprivkey(redeemPubKey)
sig = privkey.sign(sighash) + bytes([SIGHASH_ALL])
txin.scriptSig = CScript([sig, privkey.pub, OP_FALSE, redeemScript])
# exit()
# print("txin.scriptSig", b2x(txin.scriptSig))
txin_scriptPubKey = redeemScript.to_p2sh_scriptPubKey()
# print('Redeem txhex', b2x(tx.serialize()))
VerifyScript(txin.scriptSig, txin_scriptPubKey, tx, 0,
(SCRIPT_VERIFY_P2SH, ))
print("script verified, sending raw tx")
txid = zcashd.sendrawtransaction(tx)
print("Txid of submitted redeem tx: ", b2x(lx(b2x(txid))))
return b2x(lx(b2x(txid)))
# ================= AFTER 48 HRS: ALICE REFUNDS AFTER BOB TIMES OUT =========================
# Mock passage of time -- comment out to test normal redeem condition
# zcashd.generate(25)
if (zcashd.getblockcount() >= redeemblocknum):
print(
"Alice -- Bob did not redeem the Zcash you put in escrow within the timeout period, so refunding you..... "
)
txin = CMutableTxIn(COutPoint(fund_tx, fund_vout))
# The default nSequence of FFFFFFFF won't let you redeem when there's a CHECKTIMELOCKVERIFY
txin.nSequence = 0
txout = CMutableTxOut(send_amount - FEE, alicepubkey.to_scriptPubKey())
# Create the unsigned raw transaction.
tx = CMutableTransaction([txin], [txout])
# nLockTime needs to be at least as large as parameter of CHECKLOCKTIMEVERIFY for script to verify
tx.nLockTime = redeemblocknum
# Calculate the signature hash for that transaction. Note how the script we use
# is the redeemScript, not the scriptPubKey. EvalScript() will be evaluating the redeemScript
sighash = SignatureHash(zec_redeemScript, tx, 0, SIGHASH_ALL)
sig = alice_seckey.sign(sighash) + bytes([SIGHASH_ALL])
txin.scriptSig = CScript(
[sig, alice_seckey.pub, OP_FALSE, zec_redeemScript])
print("Time lock has passed, Alice redeeming her own tx:")
print("Refund tx hex:", b2x(tx.serialize()))
VerifyScript(txin.scriptSig, txin_scriptPubKey, tx, 0,
(SCRIPT_VERIFY_P2SH, ))
txid = zcashd.sendrawtransaction(tx)
print("Txid of submitted refund tx: ", b2x(lx(b2x(txid))))
quit()
# ================= BEFORE 48 HRS: BOB REDEEMS WITH ALICE'S REVEALED SECRET =========================
def auto_redeem(contract, secret):
# How to find redeemScript and redeemblocknum from blockchain?
print("Contract in auto redeem", contract.__dict__)
p2sh = contract.p2sh
#checking there are funds in the address
amount = check_funds(p2sh)
if (amount == 0):
print("address ", p2sh, " not funded")
quit()
fundtx = find_transaction_to_address(p2sh)
amount = fundtx['amount'] / COIN
p2sh = P2SHBitcoinAddress(p2sh)
if fundtx['address'] == p2sh:
print("Found {0} in p2sh {1}, redeeming...".format(amount, p2sh))
# Parsing redeemblocknum from the redeemscript of the p2sh
redeemblocknum = find_redeemblocknum(contract)
blockcount = zcashd.getblockcount()
print("\nCurrent blocknum at time of redeem on Zcash chain:",
blockcount)
if blockcount < redeemblocknum:
redeemPubKey = find_redeemAddr(contract)
print('redeemPubKey', redeemPubKey)
else:
print("nLocktime exceeded, refunding")
redeemPubKey = find_refundAddr(contract)
print('refundPubKey', redeemPubKey)
# redeemPubKey = CBitcoinAddress.from_scriptPubKey(redeemPubKey)
# exit()
zec_redeemScript = CScript(x(contract.redeemScript))
txin = CMutableTxIn(fundtx['outpoint'])
txout = CMutableTxOut(fundtx['amount'] - FEE,
redeemPubKey.to_scriptPubKey())
# Create the unsigned raw transaction.
tx = CMutableTransaction([txin], [txout])
# nLockTime needs to be at least as large as parameter of CHECKLOCKTIMEVERIFY for script to verify
# TODO: these things like redeemblocknum should really be properties of a tx class...
# Need: redeemblocknum, zec_redeemScript, secret (for creator...), txid, redeemer...
if blockcount >= redeemblocknum:
print("\nLocktime exceeded")
tx.nLockTime = redeemblocknum
sighash = SignatureHash(zec_redeemScript, tx, 0, SIGHASH_ALL)
# TODO: figure out how to better protect privkey
privkey = zcashd.dumpprivkey(redeemPubKey)
sig = privkey.sign(sighash) + bytes([SIGHASH_ALL])
print("SECRET", secret)
preimage = secret.encode('utf-8')
txin.scriptSig = CScript(
[sig, privkey.pub, preimage, OP_TRUE, zec_redeemScript])
# exit()
# print("txin.scriptSig", b2x(txin.scriptSig))
txin_scriptPubKey = zec_redeemScript.to_p2sh_scriptPubKey()
# print('Redeem txhex', b2x(tx.serialize()))
VerifyScript(txin.scriptSig, txin_scriptPubKey, tx, 0,
(SCRIPT_VERIFY_P2SH, ))
print("script verified, sending raw tx")
txid = bitcoind.sendrawtransaction(tx)
print("Txid of submitted redeem tx: ", b2x(lx(b2x(txid))))
return b2x(lx(b2x(txid)))
else:
print("No contract for this p2sh found in database", p2sh)