Add zec p2sh script, must install python-zcashlib

zec-p2sh-htlc.py

@@ -0,0 +1,90 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2017 the python-zcashlib developers
+
+import sys
+if sys.version_info.major < 3:
+    sys.stderr.write('Sorry, Python 3.x required by this example.\n')
+    sys.exit(1)
+
+import zcash
+import zcash.rpc
+from zcash import SelectParams
+from zcash.core import b2x, lx, COIN, COutPoint, CMutableTxOut, CMutableTxIn, CMutableTransaction, Hash160
+from zcash.core.script import CScript, OP_DUP, OP_IF, OP_ELSE, OP_DROP, OP_ENDIF, OP_HASH160, OP_SHA256, OP_EQUAL, OP_EQUALVERIFY, OP_CHECKSIG, SignatureHash, SIGHASH_ALL, SIGHASH_ANYONECANPAY, OP_TRUE
+from zcash.core.scripteval import VerifyScript, SCRIPT_VERIFY_P2SH
+from zcash.wallet import CBitcoinAddress, CBitcoinSecret
+import hashlib
+
+SelectParams('regtest')
+proxy = zcash.rpc.Proxy()
+
+# The parameters needed for the htlc - hash preimage, sender/seller address, recipient/buyer address, num of blocks for timeout
+preimage = b'preimage'
+h = hashlib.sha256(preimage).digest()
+
+# proxy.getnewaddress() returns CBitcoinAddress
+recipientpubkey = proxy.getnewaddress()
+senderpubkey = proxy.getnewaddress()
+# privkey of the recipient, used to sign the redeemTx
+seckey = proxy.dumpprivkey(recipientpubkey)
+
+blocknum = 7
+# Create a htlc redeemScript. Similar to a scriptPubKey the redeemScript must be
+# satisfied for the funds to be spent.
+txin_redeemScript = CScript([OP_IF, OP_SHA256, h, OP_EQUALVERIFY,OP_DUP, OP_HASH160,
+                             recipientpubkey, OP_ELSE, blocknum, OP_DROP, OP_HASH160,
+                             senderpubkey, OP_ENDIF,OP_EQUALVERIFY, OP_CHECKSIG])
+print("redeem script:", b2x(txin_redeemScript))
+
+# Create P2SH scriptPubKey from redeemScript.
+txin_scriptPubKey = txin_redeemScript.to_p2sh_scriptPubKey()
+print("p2sh_scriptPubKey", b2x(txin_scriptPubKey))
+
+# Convert the P2SH scriptPubKey to a base58 Bitcoin address
+txin_p2sh_address = CBitcoinAddress.from_scriptPubKey(txin_scriptPubKey)
+p2sh = str(txin_p2sh_address)
+print('Pay to:', p2sh)
+
+# AUTOMATE Send funds to p2sh
+amount = 1.0*COIN
+fund_tx = proxy.sendtoaddress(txin_p2sh_address, amount)
+
+print('Now redeeming.........')
+
+# AUTOMATE getting vout of funding tx
+txinfo = proxy.gettransaction(fund_tx)
+details = txinfo['details'][0]
+vout = details['vout']
+
+# Create the txin structure. scriptSig defaults to being empty.
+# The input is the p2sh funding transaction txid, vout is its index
+txin = CMutableTxIn(COutPoint(fund_tx, vout))
+
+# Create the txout. Pays out to recipient, so uses recipient's pubkey
+# Withdraw full amount minus fee
+default_fee = 0.001*COIN
+txout = CMutableTxOut(amount - default_fee, recipientpubkey.to_scriptPubKey())
+
+# Create the unsigned raw transaction.
+tx = CMutableTransaction([txin], [txout])
+
+# 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(txin_redeemScript, tx, 0, SIGHASH_ALL)
+
+# Now sign it. We have to append the type of signature we want to the end, in
+# this case the usual SIGHASH_ALL.
+sig = seckey.sign(sighash) + bytes([SIGHASH_ALL])
+
+# Set the scriptSig of our transaction input appropriately.
+txin.scriptSig = CScript([ sig, seckey.pub, preimage, OP_TRUE, txin_redeemScript])
+
+print("Redeem tx hex:", b2x(tx.serialize()))
+
+# Verify the signature worked.
+VerifyScript(txin.scriptSig, txin_scriptPubKey, tx, 0, (SCRIPT_VERIFY_P2SH,))
+
+print("Now sending redeem transaction.......")
+txid = proxy.sendrawtransaction(tx)
+print("Txid of submitted redeem tx: ", b2x(txid))