Merge old branch 'segwit' (early part) into setwit

bitcoin/script.py

@@ -43,6 +43,13 @@ def toAddress(cls, addr):
 		elif ver == 5 or ver == 196:
 			return b'\xa9\x14' + pubkeyhash + b'\x87'
 		raise ValueError('invalid address version')
+
+	@classmethod
+	def commitment(cls, commitment):
+		clen = len(commitment)
+		if clen > 0x4b:
+			raise NotImplementedError
+		return b'\x6a' + bytes((clen,)) + commitment
 
 def countSigOps(s):
 	# FIXME: don't count data as ops

bitcoin/txn.py

@@ -22,10 +22,16 @@
 _nullprev = b'\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0'
 
 class Txn:
-	def __init__(self, data=None):
+	def __init__(self, data=None, txid=None):
 		if data:
 			self.data = data
-			self.idhash()
+			if txid:
+				self.txid = txid
+			else:
+				try:
+					self.idhash()
+				except NotImplementedError:
+					pass
 
 	@classmethod
 	def new(cls):
@@ -49,6 +55,9 @@ def addOutput(self, amount, pkScript):
 		self.outputs.append( (amount, pkScript) )
 
 	def disassemble(self, retExtra = False):
+		if self.data[4:6] == b'\0\1':
+			raise NotImplementedError
+
 		self.version = unpack('<L', self.data[:4])[0]
 		rc = [4]
 
@@ -115,7 +124,21 @@ def assemble(self):
 		self.idhash()
 
 	def idhash(self):
+		if self.data[4:6] == b'\0\1':
+			if hasattr(self, 'txid'):
+				del self.txid
+			raise NotImplementedError
 		self.txid = dblsha(self.data)
+		if hasattr(self, 'witness_hash'):
+			del self.witness_hash
+
+	def withash(self):
+		self.witness_hash = dblsha(self.data)
+
+	def get_witness_hash(self):
+		if not hasattr(self, 'witness_hash'):
+			self.withash()
+		return self.witness_hash
 
 # Txn tests
 def _test():

eloipool.py

@@ -103,7 +103,10 @@ def RaiseRedFlags(reason):
 import subprocess
 from time import time
 
-def makeCoinbaseTxn(coinbaseValue, useCoinbaser = True, prevBlockHex = None):
+def makeCoinbaseTxn(coinbaseValue, useCoinbaser = True, prevBlockHex = None, witness_commitment = NotImplemented):
+	if witness_commitment is NotImplemented:
+		raise NotImplementedError
+
 	txn = Txn.new()
 
 	if useCoinbaser and hasattr(config, 'CoinbaserCmd') and config.CoinbaserCmd:
@@ -131,6 +134,10 @@ def makeCoinbaseTxn(coinbaseValue, useCoinbaser = True, prevBlockHex = None):
 	pkScript = BitcoinScript.toAddress(config.TrackerAddr)
 	txn.addOutput(coinbaseValue, pkScript)
 
+	# SegWit commitment
+	if not witness_commitment is None:
+		txn.addOutput(0, BitcoinScript.commitment(WitnessMagic + witness_commitment))
+
 	# TODO
 	# TODO: red flag on dupe coinbase
 	return txn

merklemaker.py

@@ -45,6 +45,18 @@ def SplitRuleFlag(ruleflag):
 	else:
 		return (False, ruleflag)
 
+def CalculateWitnessCommitment(txnobjs, nonce):
+	gentx_withash = b'\0' * 0x20
+	withashes = (gentx_withash,) + tuple(a.get_witness_hash() for a in txnobjs[1:])
+	txids = (gentx_withash,) + tuple(a.txid for a in txnobjs[1:])
+	if withashes == txids:
+		# Unnecessary
+		return None
+
+	wmr = MerkleTree(data=withashes).merkleRoot()
+	commitment = dblsha(wmr + nonce)
+	return commitment
+
 def MakeBlockHeader(MRD):
 	(merkleRoot, merkleTree, coinbase, prevBlock, bits) = MRD[:5]
 	BlockVersionBytes = merkleTree.MP['_BlockVersionBytes']
@@ -94,6 +106,7 @@ def __init__(self, *a, **k):
 		self.currentBlock = (None, None, None)
 		self.lastBlock = (None, None, None)
 		self.SubsidyAlgo = lambda height: 5000000000 >> (height // 210000)
+		self.WitnessNonce = b'\0' * 0x20
 
 	def _prepare(self):
 		self.UseTemplateChecks = True
@@ -181,11 +194,13 @@ def UpdateClearMerkleTree(self, MT, MP):
 
 	def createClearMerkleTree(self, height):
 		subsidy = self.SubsidyAlgo(height)
-		cbtxn = self.makeCoinbaseTxn(subsidy, False)
+		cbtxn = self.makeCoinbaseTxn(subsidy, False, witness_commitment=None)
+		cbtxn.setCoinbase(b'\0\0')  # necessary to avoid triggering segwit marker+flags
 		cbtxn.assemble()
 		MT = MerkleTree([cbtxn])
 		if self.currentMerkleTree:
 			self.UpdateClearMerkleTree(MT, self.currentMerkleTree.MP)
+		MT.witness_commitment = None
 		return MT
 
 	def updateBlock(self, newBlock, height = None, bits = None, _HBH = None):
@@ -295,15 +310,17 @@ def _APOT(self, txninfopot, MP, POTInfo):
 		return True
 
 	def _makeBlockSafe(self, MP, txnlist, txninfo):
+		sizelimit = MP.get('sizelimit', 1000000) - 0x10000  # 64 KB breathing room
 		blocksize = sum(map(len, txnlist)) + 80
-		while blocksize > 934464:  # 1 "MB" limit - 64 KB breathing room
+		while blocksize > sizelimit:
 			txnsize = len(txnlist[-1])
 			self._trimBlock(MP, txnlist, txninfo, 'SizeLimit', lambda x: 'Making blocks over 1 MB size limit (%d bytes; %s)' % (blocksize, x))
 			blocksize -= txnsize
 
 		# NOTE: This check doesn't work at all without BIP22 transaction obj format
+		sigoplimit = MP.get('sigoplimit', 20000) - 0x200  # 512 sigop breathing room
 		blocksigops = sum(a.get('sigops', 0) for a in txninfo)
-		while blocksigops > 19488:  # 20k limit - 0x200 breathing room
+		while blocksigops > sigoplimit:
 			txnsigops = txninfo[-1]['sigops']
 			self._trimBlock(MP, txnlist, txninfo, 'SigOpLimit', lambda x: 'Making blocks over 20k SigOp limit (%d; %s)' % (blocksigops, x))
 			blocksigops -= txnsigops
@@ -429,20 +446,27 @@ def _ProcessGBT(self, MP, TS = None):
 			self.logger.error('Template from \'%s\' should be trimmed, but requires unsupported rule(s)', TS['name'])
 			return None
 
-		cbtxn = self.makeCoinbaseTxn(MP['coinbasevalue'], prevBlockHex = MP['previousblockhash'])
+		txnobjs = [None]
+		for i in range(len(txnlist)):
+			iinfo = txninfo[i]
+			ka = {}
+			if 'txid' in iinfo:
+				ka['txid'] = iinfo['txid']
+			txnobjs.append(Txn(data=txnlist[i], **ka))
+
+		witness_commitment = CalculateWitnessCommitment(txnobjs, self.WitnessNonce)
+
+		cbtxn = self.makeCoinbaseTxn(MP['coinbasevalue'], prevBlockHex = MP['previousblockhash'], witness_commitment=witness_commitment)
 		cbtxn.setCoinbase(b'\0\0')
 		cbtxn.assemble()
-		txnlist.insert(0, cbtxn.data)
-		txninfo.insert(0, {
-		})
-
-		txnlist = [a for a in map(Txn, txnlist[1:])]
-		txnlist.insert(0, cbtxn)
-		txnlist = list(txnlist)
-		newMerkleTree = MerkleTree(txnlist)
+		txnobjs[0] = cbtxn
+
+		txnobjs = list(txnobjs)
+		newMerkleTree = MerkleTree(txnobjs)
 		newMerkleTree.POTInfo = MP.get('POTInfo')
 		newMerkleTree.MP = MP
 		newMerkleTree.oMP = oMP
+		newMerkleTree.witness_commitment = witness_commitment
 
 		return newMerkleTree
 
@@ -856,9 +880,9 @@ def MBS(LO = 0):
 	txninfo[2]['fee'] = 0
 	assert MBS(1) == (MP, txnlist, txninfo)
 	# _ProcessGBT tests
-	def makeCoinbaseTxn(coinbaseValue, useCoinbaser = True, prevBlockHex = None):
+	def makeCoinbaseTxn(coinbaseValue, useCoinbaser = True, prevBlockHex = None, witness_commitment=None):
 		txn = Txn.new()
-		txn.addOutput(coinbaseValue, b'')
+		txn.addOutput(coinbaseValue, BitcoinScript.commitment(witness_commitment) if witness_commitment else b'')
 		return txn
 	MM.makeCoinbaseTxn = makeCoinbaseTxn
 	MM.updateBlock = lambda *a, **ka: None