class ExecutionEngine():
_Table = None
_Service = None
_ScriptContainer = None
_Crypto = None
_VMState = VMState.BREAK
_InvocationStack = None
_EvaluationStack = None
_AltStack = None
@property
def ScriptContainer(self):
return self._ScriptContainer
@property
def Crypto(self):
return self._Crypto
@property
def State(self):
return self._VMState
@property
def InvocationStack(self):
return self._InvocationStack
@property
def EvaluationStack(self):
return self._EvaluationStack
@property
def AltStack(self):
return self._AltStack
@property
def CurrentContext(self):
return self._InvocationStack.Peek()
@property
def CallingContext(self):
if self._InvocationStack.Count > 1:
return self.InvocationStack.Peek(1)
return None
@property
def EntryContext(self):
return self.InvocationStack.Peek(self.InvocationStack.Count - 1)
def __init__(self, container=None, crypto=None, table=None, service=None):
self._ScriptContainer = container
self._Crypto = crypto
self._Table = table
self._Service = service
self._InvocationStack = RandomAccessStack(name='Invocation')
self._EvaluationStack = RandomAccessStack(name='Evaluation')
self._AltStack = RandomAccessStack(name='Alt')
def AddBreakPoint(self, position):
self.CurrentContext.Breakpoints.add(position)
def Dispose(self):
while self._InvocationStack.Count > 0:
self._InvocationStack.Pop().Dispose()
def Execute(self):
self._VMState &= ~VMState.BREAK
# while (!State.HasFlag(VMState.HALT) & & !State.HasFlag(VMState.FAULT) & & !State.HasFlag(VMState.BREAK))
# StepInto();
while self._VMState & VMState.HALT == 0 and self._VMState & VMState.FAULT == 0 and self._VMState & VMState.BREAK == 0:
self.StepInto()
def ExecuteOp(self, opcode, context):
estack = self._EvaluationStack
istack = self._InvocationStack
astack = self._AltStack
if opcode > PUSH16 and opcode != RET and context.PushOnly:
self._VMState |= VMState.FAULT
if opcode >= PUSHBYTES1 and opcode <= PUSHBYTES75:
estack.PushT(
context.OpReader.ReadBytes(int.from_bytes(opcode, 'little')))
else:
# push values
pushops = [
PUSHM1, PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8,
PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16
]
if opcode == PUSH0:
estack.PushT(bytearray([0]))
elif opcode == PUSHDATA1:
lenngth = context.OpReader.ReadByte()
estack.PushT(bytearray(context.OpReader.ReadBytes(lenngth)))
elif opcode == PUSHDATA2:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt16()))
elif opcode == PUSHDATA4:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt32()))
elif opcode in pushops:
# EvaluationStack.Push((int)opcode - (int)OpCode.PUSH1 + 1);
topush = int.from_bytes(opcode, 'little') - int.from_bytes(
PUSH1, 'little') + 1
estack.PushT(topush)
#control
elif opcode == NOP:
pass
elif opcode in [JMP, JMPIF, JMPIFNOT]:
offset = context.OpReader.ReadInt16()
offset = context.InstructionPointer + offset - 3
if offset < 0 or offset > len(context.Script):
self._VMSTATE |= VMState.FAULT
return
fValue = True
if opcode > JMP:
fValue = estack.Pop().GetBoolean()
if opcode == JMPIFNOT:
fValue = not fValue
if fValue:
context.SetInstructionPointer(offset)
elif opcode == CALL:
istack.PushT(context.Clone())
context.SetInstructionPointer(context.InstructionPointer + 2)
self.ExecuteOp(JMP, self.CurrentContext)
elif opcode == RET:
istack.Pop().Dispose()
if istack.Count == 0:
self._VMState |= VMState.HALT
elif opcode == APPCALL or opcode == TAILCALL:
if self._Table == None:
self._VMState |= VMState.FAULT
return
script_hash = UInt160(
data=context.OpReader.ReadBytes(20)).ToBytes()
script = self._Table.GetScript(script_hash)
if script == None:
self._VMState |= VMState.FAULT
return
if opcode == TAILCALL:
istack.Pop().Dispose()
self.LoadScript(script)
elif opcode == SYSCALL:
if not self._Service.Invoke(
context.OpReader.ReadVarBytes(252).decode('ascii'),
self):
self._VMState |= VMState.FAULT
#stack operations
elif opcode == DUPFROMALTSTACK:
estack.PushT(astack.Peek())
elif opcode == TOALTSTACK:
astack.PushT(estack.Pop())
elif opcode == FROMALTSTACK:
estack.PushT(astack.Pop())
elif opcode == XDROP:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
estack.Remove(n)
elif opcode == XSWAP:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
#if n == 0 break, same as do x if n > 0
if n > 0:
item = estack.Peek(n)
estack.Set(n, estack.Peek())
estack.Set(0, item)
elif opcode == XTUCK:
n = estack.Pop().GetBigInteger()
if n <= 0:
self._VMState |= VMState.FAULT
return
estack.Insert(n, estack.Peek())
elif opcode == DEPTH:
estack.PushT(estack.Count)
elif opcode == DROP:
estack.Pop()
elif opcode == DUP:
estack.PushT(estack.Peek())
elif opcode == NIP:
x2 = estack.Pop()
estack.Pop()
estack.PushT(x2)
elif opcode == OVER:
x2 = estack.Pop()
x1 = estack.Peek()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == PICK:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
estack.PushT(estack.Peek(n))
elif opcode == ROLL:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
if n > 0:
estack.PushT(estack.Remove(n))
elif opcode == ROT:
x3 = estack.Pop()
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x3)
estack.PushT(x1)
elif opcode == SWAP:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == TUCK:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
estack.PushT(x2)
elif opcode == CAT:
x2 = estack.Pop().GetByteArray()
x1 = estack.Pop().GetByteArray()
estack.PushT(x1 + x2)
elif opcode == SUBSTR:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
index = estack.Pop().GetBigInteger()
if index < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
estack.PushT(x[index:count])
elif opcode == LEFT:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
estack.PushT(x[:count])
elif opcode == RIGHT:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
if len(x) < count:
self._VMState |= VMState.FAULT
return
estack.PushT(x[-count:])
elif opcode == SIZE:
x = estack.Pop().GetByteArray()
estack.PushT(len(x))
elif opcode == INVERT:
x = estack.Pop().GetBigInteger()
estack.PushT(~x)
elif opcode == AND:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 & x2)
elif opcode == OR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 | x2)
elif opcode == XOR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 ^ x2)
elif opcode == EQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
res = x1.Equals(x2)
estack.PushT(x1.Equals(x2))
#numeric
elif opcode == INC:
x = estack.Pop().GetBigInteger()
estack.PushT(x + 1)
elif opcode == DEC:
x = estack.Pop().GetBigInteger()
estack.PushT(x - 1)
elif opcode == SIGN:
##### Make sure to implement sign for big integer
x = estack.Pop().GetBigInteger()
estack.PushT(x.Sign)
elif opcode == NEGATE:
x = estack.Pop().GetBigInteger()
estack.PushT(-x)
elif opcode == ABS:
x = estack.Pop().GetBigInteger()
estack.PushT(abs(x))
elif opcode == NOT:
x = estack.Pop().GetBigInteger()
estack.PushT(not x)
elif opcode == NZ:
x = estack.Pop().GetBigInteger()
estack.PushT(x is not 0)
elif opcode == ADD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 + x2)
elif opcode == SUB:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
# print("x2, x1 %s .. %s " % (x2, x1))
estack.PushT(x1 - x2)
elif opcode == MUL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 * x2)
elif opcode == DIV:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 / x2)
elif opcode == MOD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 % x2)
elif opcode == SHL:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x << n)
elif opcode == SHR:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x >> n)
elif opcode == BOOLAND:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 and x2)
elif opcode == BOOLOR:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 or x2)
elif opcode == NUMEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 == x2)
elif opcode == NUMNOTEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 != x2)
elif opcode == LT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 < x2)
elif opcode == GT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 > x2)
elif opcode == LTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 <= x2)
elif opcode == GTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 >= x2)
elif opcode == MIN:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(min(x1, x2))
elif opcode == MAX:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(max(x1, x2))
elif opcode == WITHIN:
b = estack.Pop().GetBigInteger()
a = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(a <= x and x < b)
#CRyPTO
elif opcode == SHA1:
h = hashlib.sha1(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == SHA256:
h = hashlib.sha256(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == HASH160:
estack.PushT(self.Crypto.Hash160(estack.Pop().GetByteArray()))
elif opcode == HASH256:
estack.PushT(self.Crypto.Hash256(estack.Pop().GetByteArray()))
elif opcode == CHECKSIG:
pubkey = estack.Pop().GetByteArray()
sig = estack.Pop().GetByteArray()
try:
self.Crypto.VerifySignature(
self.ScriptContainer.GetMessage(), pubkey, sig)
except Exception as e:
estack.PushT(False)
elif opcode == CHECKMULTISIG:
n = estack.Pop().GetBigInteger()
if n < 1:
self._VMState |= VMState.FAULT
return
pubkeys = []
for i in range(0, n):
pubkeys[i] = estack.Pop().GetByteArray()
m = estack.Pop().GetBigInteger()
if m < 1 or m > n:
self._VMState |= VMState.FAULT
return
sigs = []
for i in range(0, m):
m[i] = estack.Pop().GetByteArray()
message = self.ScriptContainer.GetMessage()
fSuccess = True
try:
i = 0
j = 0
while fSuccess and i < m and j < n:
if self.Crypto.VerifySignature(message, sigs[i],
pubkeys[j]):
i += 1
j += 1
if m - i > j - n:
fSuccess = False
except Exception as e:
fSuccess = False
estack.PushT(fSuccess)
#lists
elif opcode == ARRAYSIZE:
item = estack.Pop()
if not item.IsArray:
estack.PushT(len(item.GetByteArray()))
else:
estack.PushT(len(item.GetArray()))
elif opcode == PACK:
size = estack.Pop().GetBigInteger()
if size < 0 or size > estack.Count:
self._VMState |= VMState.FAULT
return
items = []
for i in range(0, size):
items.append(estack.Pop())
estack.PushT(items)
elif opcode == UNPACK:
item = estack.Pop()
if not item.IsArray:
self._VMState |= VMState.FAULT
return
items = item.GetArray()
items.reverse()
[estack.PushT(i) for i in items]
estack.PushT(len(items))
elif opcode == PICKITEM:
index = estack.Pop().GetBigInteger()
if index < 0:
self._VMState |= VMState.FAULT
return
item = estack.Pop()
if not item.IsArray:
self._VMState |= VMState.FAULT
return
items = item.GetArray()
if index >= len(items):
self._VMState |= VMState.FAULT
return
estack.PushT(items[index])
elif opcode == SETITEM:
newItem = estack.Pop()
if newItem.IsStruct:
newItem = newItem.Clone()
index = estack.Pop().GetBigInteger()
arrItem = estack.Pop()
if not arrItem.IsArray:
self._VMState |= VMState.FAULT
return
items = arrItem.GetArray()
if index < 0 or index >= len(items):
self._VMState |= VMState.FAULT
return
items[index] = newItem
elif opcode == NEWARRAY:
count = estack.Pop().GetBigInteger()
items = [None for i in range(0, count)]
estack.PushT(Array(items))
elif opcode == NEWSTRUCT:
count = estack.Pop().GetBigInteger()
items = [None for i in range(0, count)]
estack.PushT(Struct(items))
else:
self._VMState |= VMState.FAULT
return
if self._VMState & VMState.FAULT == 0 and self.InvocationStack.Count > 0:
if self.CurrentContext.InstructionPointer in self.CurrentContext.Breakpoints:
self._VMState |= VMState.BREAK
def LoadScript(self, script, push_only=False):
context = ExecutionContext(self, script, push_only)
self._InvocationStack.PushT(context)
def RemoveBreakPoint(self, position):
if self._InvocationStack.Count == 0:
return False
return self.CurrentContext.Breakpoints.remove(position)
def StepInto(self):
if self._InvocationStack.Count == 0:
self._VMState |= VMState.HALT
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
self.__log.debug("stopping because vm state is %s " %
self._VMState)
op = None
if self.CurrentContext.InstructionPointer >= len(
self.CurrentContext.Script):
op = RET
else:
op = self.CurrentContext.OpReader.ReadByte(do_ord=False)
opname = ToName(op)
# print("____________________________________________________")
# print("%s -> %s" % (op, opname))
# print("-----------------------------------")
try:
self.ExecuteOp(op, self.CurrentContext)
except Exception as e:
print("could not execute op %s " % e)
traceback.print_stack()
traceback.print_exc()
raise e
def StepOut(self):
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
def StepOver(self):
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
return
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
class ExecutionEngine():
_Table = None
_Service = None
_ScriptContainer = None
_Crypto = None
_VMState = VMState.BREAK
_InvocationStack = None
_EvaluationStack = None
_AltStack = None
_ExecutedScriptHashes = None
ops_processed = 0
@property
def ScriptContainer(self):
return self._ScriptContainer
@property
def Crypto(self):
return self._Crypto
@property
def State(self):
return self._VMState
@property
def InvocationStack(self):
return self._InvocationStack
@property
def EvaluationStack(self):
return self._EvaluationStack
@property
def AltStack(self):
return self._AltStack
@property
def CurrentContext(self):
return self._InvocationStack.Peek()
@property
def CallingContext(self):
if self._InvocationStack.Count > 1:
return self.InvocationStack.Peek(1)
return None
@property
def EntryContext(self):
return self.InvocationStack.Peek(self.InvocationStack.Count - 1)
@property
def ExecutedScriptHashes(self):
return self._ExecutedScriptHashes
def __init__(self, container=None, crypto=None, table=None, service=None):
self._ScriptContainer = container
self._Crypto = crypto
self._Table = table
self._Service = service
self._InvocationStack = RandomAccessStack(name='Invocation')
self._EvaluationStack = RandomAccessStack(name='Evaluation')
self._AltStack = RandomAccessStack(name='Alt')
self._ExecutedScriptHashes = []
self.ops_processed = 0
def AddBreakPoint(self, position):
self.CurrentContext.Breakpoints.add(position)
def ResultsForCode(self, contract):
try:
return_type = ContractParameterType(contract.ReturnType)
item = self.EvaluationStack.Items[0]
if return_type == ContractParameterType.Integer:
return item.GetBigInteger()
elif return_type == ContractParameterType.Boolean:
return item.GetBoolean()
elif return_type == ContractParameterType.ByteArray:
return item.GetByteArray()
elif return_type == ContractParameterType.String:
return item.GetString()
elif return_type == ContractParameterType.Array:
return item.GetArray()
else:
logger.error("Could not format results for return type %s " %
return_type)
return item
except Exception as e:
pass
return self.EvaluationStack.Items
def Dispose(self):
while self._InvocationStack.Count > 0:
self._InvocationStack.Pop().Dispose()
def Execute(self):
self._VMState &= ~VMState.BREAK
while self._VMState & VMState.HALT == 0 and self._VMState & VMState.FAULT == 0 and self._VMState & VMState.BREAK == 0:
self.StepInto()
def ExecuteOp(self, opcode, context):
estack = self._EvaluationStack
istack = self._InvocationStack
astack = self._AltStack
if opcode > PUSH16 and opcode != RET and context.PushOnly:
self._VMState |= VMState.FAULT
if opcode >= PUSHBYTES1 and opcode <= PUSHBYTES75:
bytestoread = context.OpReader.ReadBytes(
int.from_bytes(opcode, 'little'))
estack.PushT(bytestoread)
else:
# push values
pushops = [
PUSHM1, PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8,
PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16
]
if opcode == PUSH0:
estack.PushT(bytearray([0]))
elif opcode == PUSHDATA1:
lenngth = context.OpReader.ReadByte()
estack.PushT(bytearray(context.OpReader.ReadBytes(lenngth)))
elif opcode == PUSHDATA2:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt16()))
elif opcode == PUSHDATA4:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt32()))
elif opcode in pushops:
# EvaluationStack.Push((int)opcode - (int)OpCode.PUSH1 + 1);
topush = int.from_bytes(opcode, 'little') - int.from_bytes(
PUSH1, 'little') + 1
estack.PushT(topush)
# control
elif opcode == NOP:
pass
elif opcode in [JMP, JMPIF, JMPIFNOT]:
offset_b = context.OpReader.ReadInt16()
offset = context.InstructionPointer + offset_b - 3
if offset < 0 or offset > len(context.Script):
self._VMState |= VMState.FAULT
return
fValue = True
if opcode > JMP:
fValue = estack.Pop().GetBoolean()
if opcode == JMPIFNOT:
fValue = not fValue
if fValue:
context.SetInstructionPointer(offset)
elif opcode == CALL:
istack.PushT(context.Clone())
context.SetInstructionPointer(context.InstructionPointer + 2)
self.ExecuteOp(JMP, self.CurrentContext)
elif opcode == RET:
istack.Pop().Dispose()
if istack.Count == 0:
self._VMState |= VMState.HALT
elif opcode == APPCALL or opcode == TAILCALL:
if self._Table is None:
self._VMState |= VMState.FAULT
return
script_hash = context.OpReader.ReadBytes(20)
is_normal_call = False
for b in script_hash:
if b > 0:
is_normal_call = True
if not is_normal_call:
script_hash = self.EvaluationStack.Pop().GetByteArray()
script = self._Table.GetScript(
UInt160(data=script_hash).ToBytes())
if script is None:
logger.error(
"Could not find script from script table: %s " %
script_hash)
self._VMState |= VMState.FAULT
return
if opcode == TAILCALL:
istack.Pop().Dispose()
self.LoadScript(script)
elif opcode == SYSCALL:
call = context.OpReader.ReadVarBytes(252).decode('ascii')
if not self._Service.Invoke(call, self):
self._VMState |= VMState.FAULT
# stack operations
elif opcode == DUPFROMALTSTACK:
estack.PushT(astack.Peek())
elif opcode == TOALTSTACK:
astack.PushT(estack.Pop())
elif opcode == FROMALTSTACK:
estack.PushT(astack.Pop())
elif opcode == XDROP:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
estack.Remove(n)
elif opcode == XSWAP:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
# if n == 0 break, same as do x if n > 0
if n > 0:
item = estack.Peek(n)
estack.Set(n, estack.Peek())
estack.Set(0, item)
elif opcode == XTUCK:
n = estack.Pop().GetBigInteger()
if n <= 0:
self._VMState |= VMState.FAULT
return
estack.Insert(n, estack.Peek())
elif opcode == DEPTH:
estack.PushT(estack.Count)
elif opcode == DROP:
estack.Pop()
elif opcode == DUP:
estack.PushT(estack.Peek())
elif opcode == NIP:
x2 = estack.Pop()
estack.Pop()
estack.PushT(x2)
elif opcode == OVER:
x2 = estack.Pop()
x1 = estack.Peek()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == PICK:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
estack.PushT(estack.Peek(n))
elif opcode == ROLL:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
if n > 0:
estack.PushT(estack.Remove(n))
elif opcode == ROT:
x3 = estack.Pop()
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x3)
estack.PushT(x1)
elif opcode == SWAP:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == TUCK:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
estack.PushT(x2)
elif opcode == CAT:
x2 = estack.Pop().GetByteArray()
x1 = estack.Pop().GetByteArray()
estack.PushT(x1 + x2)
elif opcode == SUBSTR:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
index = estack.Pop().GetBigInteger()
if index < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
estack.PushT(x[index:count + index])
elif opcode == LEFT:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
estack.PushT(x[:count])
elif opcode == RIGHT:
count = estack.Pop().GetBigInteger()
if count < 0:
self._VMState |= VMState.FAULT
return
x = estack.Pop().GetByteArray()
if len(x) < count:
self._VMState |= VMState.FAULT
return
estack.PushT(x[-count:])
elif opcode == SIZE:
x = estack.Pop().GetByteArray()
estack.PushT(len(x))
elif opcode == INVERT:
x = estack.Pop().GetBigInteger()
estack.PushT(~x)
elif opcode == AND:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 & x2)
elif opcode == OR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 | x2)
elif opcode == XOR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 ^ x2)
elif opcode == EQUAL:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x1.Equals(x2))
# numeric
elif opcode == INC:
x = estack.Pop().GetBigInteger()
estack.PushT(x + 1)
elif opcode == DEC:
x = estack.Pop().GetBigInteger()
estack.PushT(x - 1)
elif opcode == SIGN:
# Make sure to implement sign for big integer
x = estack.Pop().GetBigInteger()
estack.PushT(x.Sign)
elif opcode == NEGATE:
x = estack.Pop().GetBigInteger()
estack.PushT(-x)
elif opcode == ABS:
x = estack.Pop().GetBigInteger()
estack.PushT(abs(x))
elif opcode == NOT:
x = estack.Pop().GetBigInteger()
estack.PushT(not x)
elif opcode == NZ:
x = estack.Pop().GetBigInteger()
estack.PushT(x is not 0)
elif opcode == ADD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 + x2)
elif opcode == SUB:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 - x2)
elif opcode == MUL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 * x2)
elif opcode == DIV:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 / x2)
elif opcode == MOD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 % x2)
elif opcode == SHL:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x << n)
elif opcode == SHR:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x >> n)
elif opcode == BOOLAND:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 and x2)
elif opcode == BOOLOR:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 or x2)
elif opcode == NUMEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x2 == x1)
elif opcode == NUMNOTEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 != x2)
elif opcode == LT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 < x2)
elif opcode == GT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 > x2)
elif opcode == LTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 <= x2)
elif opcode == GTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 >= x2)
elif opcode == MIN:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(min(x1, x2))
elif opcode == MAX:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(max(x1, x2))
elif opcode == WITHIN:
b = estack.Pop().GetBigInteger()
a = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(a <= x and x < b)
# CRyPTO
elif opcode == SHA1:
h = hashlib.sha1(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == SHA256:
h = hashlib.sha256(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == HASH160:
estack.PushT(self.Crypto.Hash160(estack.Pop().GetByteArray()))
elif opcode == HASH256:
estack.PushT(self.Crypto.Hash256(estack.Pop().GetByteArray()))
elif opcode == CHECKSIG:
pubkey = estack.Pop().GetByteArray()
sig = estack.Pop().GetByteArray()
try:
res = self.Crypto.VerifySignature(
self.ScriptContainer.GetMessage(), sig, pubkey)
estack.PushT(res)
except Exception as e:
estack.PushT(False)
logger.error("Could not checksig: %s " % e)
elif opcode == CHECKMULTISIG:
n = estack.Pop().GetBigInteger()
if n < 1:
self._VMState |= VMState.FAULT
return
pubkeys = []
for i in range(0, n):
pubkeys.append(estack.Pop().GetByteArray())
m = estack.Pop().GetBigInteger()
if m < 1 or m > n:
self._VMState |= VMState.FAULT
return
sigs = []
for i in range(0, m):
sigs.append(estack.Pop().GetByteArray())
message = self.ScriptContainer.GetMessage(
) if self.ScriptContainer else ''
fSuccess = True
try:
i = 0
j = 0
while fSuccess and i < m and j < n:
if self.Crypto.VerifySignature(message, sigs[i],
pubkeys[j]):
i += 1
j += 1
if m - i > n - j:
fSuccess = False
except Exception as e:
fSuccess = False
estack.PushT(fSuccess)
# lists
elif opcode == ARRAYSIZE:
item = estack.Pop()
if not item:
self._VMState |= VMState.FAULT
return
if not item.IsArray:
estack.PushT(len(item.GetByteArray()))
else:
estack.PushT(len(item.GetArray()))
elif opcode == PACK:
size = estack.Pop().GetBigInteger()
if size < 0 or size > estack.Count:
self._VMState |= VMState.FAULT
return
items = []
for i in range(0, size):
topack = estack.Pop()
items.append(topack)
estack.PushT(items)
elif opcode == UNPACK:
item = estack.Pop()
if not item.IsArray:
self._VMState |= VMState.FAULT
return
items = item.GetArray()
items.reverse()
[estack.PushT(i) for i in items]
estack.PushT(len(items))
elif opcode == PICKITEM:
index = estack.Pop().GetBigInteger()
if index < 0:
self._VMState |= VMState.FAULT
return
item = estack.Pop()
if not item.IsArray:
self._VMState |= VMState.FAULT
return
items = item.GetArray()
if index >= len(items):
self._VMState |= VMState.FAULT
return
to_pick = items[index]
estack.PushT(to_pick)
elif opcode == SETITEM:
newItem = estack.Pop()
if issubclass(type(newItem), StackItem) and newItem.IsStruct:
newItem = newItem.Clone()
index = estack.Pop().GetBigInteger()
arrItem = estack.Pop()
if not issubclass(type(arrItem),
StackItem) or not arrItem.IsArray:
self._VMState |= VMState.FAULT
return
items = arrItem.GetArray()
if index < 0 or index >= len(items):
self._VMState |= VMState.FAULT
return
items[index] = newItem
elif opcode == NEWARRAY:
count = estack.Pop().GetBigInteger()
items = [None for i in range(0, count)]
estack.PushT(Array(items))
elif opcode == NEWSTRUCT:
count = estack.Pop().GetBigInteger()
items = [None for i in range(0, count)]
estack.PushT(Struct(items))
elif opcode == APPEND:
newItem = estack.Pop()
if type(newItem) is Struct:
newItem = newItem.Clone()
arrItem = estack.Pop()
if not arrItem.IsArray:
self._VMState |= VMState.FAULT
return
arr = arrItem.GetArray()
arr.append(newItem)
elif opcode == REVERSE:
arrItem = estack.Pop()
if not arrItem.IsArray:
self._VMState |= VMState.FAULT
return
arrItem.GetArray().reverse()
elif opcode == REMOVE:
index = estack.Pop().GetBigInteger()
arrItem = estack.Pop()
if not arrItem.IsArray:
self._VMState |= VMState.FAULT
return
items = arrItem.GetArray()
if index < 0 or index >= len(items):
self._VMState |= VMState.FAULT
return
del items[index]
elif opcode == THROW:
self._VMState |= VMState.FAULT
return
elif opcode == THROWIFNOT:
if not estack.Pop().GetBoolean():
self._VMState |= VMState.FAULT
return
elif opcode == DEBUG:
pdb.set_trace()
return
else:
self._VMState |= VMState.FAULT
return
if self._VMState & VMState.FAULT == 0 and self.InvocationStack.Count > 0:
if self.CurrentContext.InstructionPointer in self.CurrentContext.Breakpoints:
self._VMState |= VMState.BREAK
def LoadScript(self, script, push_only=False):
context = ExecutionContext(self, script, push_only)
self._InvocationStack.PushT(context)
self._ExecutedScriptHashes.append(context.ScriptHash())
def RemoveBreakPoint(self, position):
if self._InvocationStack.Count == 0:
return False
return self.CurrentContext.Breakpoints.remove(position)
def StepInto(self):
if self._InvocationStack.Count == 0:
logger.info("INVOCATION COUNT IS 0, HALT")
self._VMState |= VMState.HALT
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
logger.info("stopping because vm state is %s " % self._VMState)
return
op = None
if self.CurrentContext.InstructionPointer >= len(
self.CurrentContext.Script):
op = RET
else:
op = self.CurrentContext.OpReader.ReadByte(do_ord=False)
# opname = ToName(op)
# logger.info("____________________________________________________")
# logger.info("[%s] %02x -> %s" % (self.ops_processed,int.from_bytes(op,byteorder='little'), opname))
# logger.info("-----------------------------------")
self.ops_processed += 1
try:
self.ExecuteOp(op, self.CurrentContext)
except Exception as e:
logger.error("COULD NOT EXECUTE OP: %s %s %s" %
(e, op, ToName(op)))
logger.exception(e)
def StepOut(self):
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
def StepOver(self):
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
return
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
class ExecutionEngine():
_Table = None
_Service = None
_ScriptContainer = None
_Crypto = None
_VMState = None
_InvocationStack = None
_EvaluationStack = None
_AltStack = None
_ExecutedScriptHashes = None
ops_processed = 0
_exit_on_error = False
log_file_name = 'vm_instructions.log'
# file descriptor
log_file = None
_is_write_log = False
_debug_map = None
_vm_debugger = None
def write_log(self, message):
"""
Write a line to the VM instruction log file.
Args:
message (str): string message to write to file.
"""
if self._is_write_log and self.log_file and not self.log_file.closed:
self.log_file.write(message + '\n')
@property
def ScriptContainer(self):
return self._ScriptContainer
@property
def Crypto(self):
return self._Crypto
@property
def State(self):
return self._VMState
@property
def InvocationStack(self):
return self._InvocationStack
@property
def EvaluationStack(self):
return self._EvaluationStack
@property
def AltStack(self):
return self._AltStack
@property
def CurrentContext(self):
return self._InvocationStack.Peek()
@property
def CallingContext(self):
if self._InvocationStack.Count > 1:
return self.InvocationStack.Peek(1)
return None
@property
def ExitOnError(self):
return self._exit_on_error
@property
def EntryContext(self):
return self.InvocationStack.Peek(self.InvocationStack.Count - 1)
@property
def ExecutedScriptHashes(self):
return self._ExecutedScriptHashes
def __init__(self,
container=None,
crypto=None,
table=None,
service=None,
exit_on_error=False):
self._VMState = VMState.BREAK
self._ScriptContainer = container
self._Crypto = crypto
self._Table = table
self._Service = service
self._exit_on_error = exit_on_error
self._InvocationStack = RandomAccessStack(name='Invocation')
self._EvaluationStack = RandomAccessStack(name='Evaluation')
self._AltStack = RandomAccessStack(name='Alt')
self._ExecutedScriptHashes = []
self.ops_processed = 0
self._debug_map = None
self._is_write_log = settings.log_vm_instructions
def AddBreakPoint(self, position):
self.CurrentContext.Breakpoints.add(position)
def LoadDebugInfoForScriptHash(self, debug_map, script_hash):
if debug_map and script_hash:
self._debug_map = debug_map
self._debug_map['script_hash'] = script_hash
def Dispose(self):
while self._InvocationStack.Count > 0:
self._InvocationStack.Pop().Dispose()
def Execute(self):
self._VMState &= ~VMState.BREAK
def loop_stepinto():
while self._VMState & VMState.HALT == 0 and self._VMState & VMState.FAULT == 0 and self._VMState & VMState.BREAK == 0:
self.StepInto()
if settings.log_vm_instructions:
with open(self.log_file_name, 'w') as self.log_file:
self.write_log(str(datetime.datetime.now()))
loop_stepinto()
else:
loop_stepinto()
def ExecuteOp(self, opcode, context):
estack = self._EvaluationStack
istack = self._InvocationStack
astack = self._AltStack
if opcode > PUSH16 and opcode != RET and context.PushOnly:
return self.VM_FAULT_and_report(VMFault.UNKNOWN1)
if opcode >= PUSHBYTES1 and opcode <= PUSHBYTES75:
bytestoread = context.OpReader.ReadBytes(
int.from_bytes(opcode, 'little'))
estack.PushT(bytestoread)
else:
# push values
pushops = [
PUSHM1, PUSH1, PUSH2, PUSH3, PUSH4, PUSH5, PUSH6, PUSH7, PUSH8,
PUSH9, PUSH10, PUSH11, PUSH12, PUSH13, PUSH14, PUSH15, PUSH16
]
if opcode == PUSH0:
estack.PushT(bytearray(0))
elif opcode == PUSHDATA1:
lenngth = context.OpReader.ReadByte()
estack.PushT(bytearray(context.OpReader.ReadBytes(lenngth)))
elif opcode == PUSHDATA2:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt16()))
elif opcode == PUSHDATA4:
estack.PushT(
context.OpReader.ReadBytes(context.OpReader.ReadUInt32()))
elif opcode in pushops:
# EvaluationStack.Push((int)opcode - (int)OpCode.PUSH1 + 1);
topush = int.from_bytes(opcode, 'little') - int.from_bytes(
PUSH1, 'little') + 1
estack.PushT(topush)
# control
elif opcode == NOP:
pass
elif opcode in [JMP, JMPIF, JMPIFNOT]:
offset_b = context.OpReader.ReadInt16()
offset = context.InstructionPointer + offset_b - 3
if offset < 0 or offset > len(context.Script):
return self.VM_FAULT_and_report(VMFault.INVALID_JUMP)
fValue = True
if opcode > JMP:
fValue = estack.Pop().GetBoolean()
if opcode == JMPIFNOT:
fValue = not fValue
if fValue:
context.SetInstructionPointer(offset)
elif opcode == CALL:
istack.PushT(context.Clone())
context.SetInstructionPointer(context.InstructionPointer + 2)
self.ExecuteOp(JMP, self.CurrentContext)
elif opcode == RET:
istack.Pop().Dispose()
if istack.Count == 0:
self._VMState |= VMState.HALT
elif opcode == APPCALL or opcode == TAILCALL:
if self._Table is None:
return self.VM_FAULT_and_report(VMFault.UNKNOWN2)
script_hash = context.OpReader.ReadBytes(20)
is_normal_call = False
for b in script_hash:
if b > 0:
is_normal_call = True
if not is_normal_call:
script_hash = self.EvaluationStack.Pop().GetByteArray()
script = self._Table.GetScript(
UInt160(data=script_hash).ToBytes())
if script is None:
logger.error(
"Could not find script from script table: %s " %
script_hash)
return self.VM_FAULT_and_report(VMFault.INVALID_CONTRACT,
script_hash)
if opcode == TAILCALL:
istack.Pop().Dispose()
self.LoadScript(script)
elif opcode == SYSCALL:
call = context.OpReader.ReadVarBytes(252).decode('ascii')
self.write_log(call)
if not self._Service.Invoke(call, self):
return self.VM_FAULT_and_report(VMFault.SYSCALL_ERROR,
call)
# stack operations
elif opcode == DUPFROMALTSTACK:
estack.PushT(astack.Peek())
elif opcode == TOALTSTACK:
astack.PushT(estack.Pop())
elif opcode == FROMALTSTACK:
estack.PushT(astack.Pop())
elif opcode == XDROP:
n = estack.Pop().GetBigInteger()
if n < 0:
self._VMState |= VMState.FAULT
return
estack.Remove(n)
elif opcode == XSWAP:
n = estack.Pop().GetBigInteger()
if n < 0:
return self.VM_FAULT_and_report(VMFault.UNKNOWN3)
# if n == 0 break, same as do x if n > 0
if n > 0:
item = estack.Peek(n)
estack.Set(n, estack.Peek())
estack.Set(0, item)
elif opcode == XTUCK:
n = estack.Pop().GetBigInteger()
if n <= 0:
return self.VM_FAULT_and_report(VMFault.UNKNOWN4)
estack.Insert(n, estack.Peek())
elif opcode == DEPTH:
estack.PushT(estack.Count)
elif opcode == DROP:
estack.Pop()
elif opcode == DUP:
estack.PushT(estack.Peek())
elif opcode == NIP:
x2 = estack.Pop()
estack.Pop()
estack.PushT(x2)
elif opcode == OVER:
x2 = estack.Pop()
x1 = estack.Peek()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == PICK:
n = estack.Pop().GetBigInteger()
if n < 0:
return self.VM_FAULT_and_report(VMFault.UNKNOWN5)
estack.PushT(estack.Peek(n))
elif opcode == ROLL:
n = estack.Pop().GetBigInteger()
if n < 0:
return self.VM_FAULT_and_report(VMFault.UNKNOWN6)
if n > 0:
estack.PushT(estack.Remove(n))
elif opcode == ROT:
x3 = estack.Pop()
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x3)
estack.PushT(x1)
elif opcode == SWAP:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
elif opcode == TUCK:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x2)
estack.PushT(x1)
estack.PushT(x2)
elif opcode == CAT:
x2 = estack.Pop().GetByteArray()
x1 = estack.Pop().GetByteArray()
estack.PushT(x1 + x2)
elif opcode == SUBSTR:
count = estack.Pop().GetBigInteger()
if count < 0:
return self.VM_FAULT_and_report(
VMFault.SUBSTR_INVALID_LENGTH)
index = estack.Pop().GetBigInteger()
if index < 0:
return self.VM_FAULT_and_report(
VMFault.SUBSTR_INVALID_INDEX)
x = estack.Pop().GetByteArray()
estack.PushT(x[index:count + index])
elif opcode == LEFT:
count = estack.Pop().GetBigInteger()
if count < 0:
return self.VM_FAULT_and_report(VMFault.LEFT_INVALID_COUNT)
x = estack.Pop().GetByteArray()
estack.PushT(x[:count])
elif opcode == RIGHT:
count = estack.Pop().GetBigInteger()
if count < 0:
return self.VM_FAULT_and_report(
VMFault.RIGHT_INVALID_COUNT)
x = estack.Pop().GetByteArray()
if len(x) < count:
return self.VM_FAULT_and_report(VMFault.RIGHT_UNKNOWN)
estack.PushT(x[-count:])
elif opcode == SIZE:
x = estack.Pop().GetByteArray()
estack.PushT(len(x))
elif opcode == INVERT:
x = estack.Pop().GetBigInteger()
estack.PushT(~x)
elif opcode == AND:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 & x2)
elif opcode == OR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 | x2)
elif opcode == XOR:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 ^ x2)
elif opcode == EQUAL:
x2 = estack.Pop()
x1 = estack.Pop()
estack.PushT(x1.Equals(x2))
# numeric
elif opcode == INC:
x = estack.Pop().GetBigInteger()
estack.PushT(x + 1)
elif opcode == DEC:
x = estack.Pop().GetBigInteger()
estack.PushT(x - 1)
elif opcode == SIGN:
# Make sure to implement sign for big integer
x = estack.Pop().GetBigInteger()
estack.PushT(x.Sign)
elif opcode == NEGATE:
x = estack.Pop().GetBigInteger()
estack.PushT(-x)
elif opcode == ABS:
x = estack.Pop().GetBigInteger()
estack.PushT(abs(x))
elif opcode == NOT:
x = estack.Pop().GetBigInteger()
estack.PushT(not x)
elif opcode == NZ:
x = estack.Pop().GetBigInteger()
estack.PushT(x is not 0)
elif opcode == ADD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 + x2)
elif opcode == SUB:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 - x2)
elif opcode == MUL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 * x2)
elif opcode == DIV:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 / x2)
elif opcode == MOD:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 % x2)
elif opcode == SHL:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x << n)
elif opcode == SHR:
n = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(x >> n)
elif opcode == BOOLAND:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 and x2)
elif opcode == BOOLOR:
x2 = estack.Pop().GetBoolean()
x1 = estack.Pop().GetBoolean()
estack.PushT(x1 or x2)
elif opcode == NUMEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x2 == x1)
elif opcode == NUMNOTEQUAL:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 != x2)
elif opcode == LT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 < x2)
elif opcode == GT:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 > x2)
elif opcode == LTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 <= x2)
elif opcode == GTE:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(x1 >= x2)
elif opcode == MIN:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(min(x1, x2))
elif opcode == MAX:
x2 = estack.Pop().GetBigInteger()
x1 = estack.Pop().GetBigInteger()
estack.PushT(max(x1, x2))
elif opcode == WITHIN:
b = estack.Pop().GetBigInteger()
a = estack.Pop().GetBigInteger()
x = estack.Pop().GetBigInteger()
estack.PushT(a <= x and x < b)
# CRyPTO
elif opcode == SHA1:
h = hashlib.sha1(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == SHA256:
h = hashlib.sha256(estack.Pop().GetByteArray())
estack.PushT(h.digest())
elif opcode == HASH160:
estack.PushT(self.Crypto.Hash160(estack.Pop().GetByteArray()))
elif opcode == HASH256:
estack.PushT(self.Crypto.Hash256(estack.Pop().GetByteArray()))
elif opcode == CHECKSIG:
pubkey = estack.Pop().GetByteArray()
sig = estack.Pop().GetByteArray()
try:
res = self.Crypto.VerifySignature(
self.ScriptContainer.GetMessage(), sig, pubkey)
estack.PushT(res)
except Exception as e:
estack.PushT(False)
logger.error("Could not checksig: %s " % e)
elif opcode == VERIFY:
pubkey = estack.Pop().GetByteArray()
sig = estack.Pop().GetByteArray()
message = estack.Pop().GetString()
try:
res = self.Crypto.VerifySignature(message, sig, pubkey)
estack.PushT(res)
except Exception as e:
estack.PushT(False)
logger.error("Could not checksig: %s " % e)
elif opcode == CHECKMULTISIG:
n = estack.Pop().GetBigInteger()
if n < 1:
return self.VM_FAULT_and_report(
VMFault.CHECKMULTISIG_INVALID_PUBLICKEY_COUNT)
pubkeys = []
for i in range(0, n):
pubkeys.append(estack.Pop().GetByteArray())
m = estack.Pop().GetBigInteger()
if m < 1 or m > n:
return self.VM_FAULT_and_report(
VMFault.CHECKMULTISIG_SIGNATURE_ERROR, m, n)
sigs = []
for i in range(0, m):
sigs.append(estack.Pop().GetByteArray())
message = self.ScriptContainer.GetMessage(
) if self.ScriptContainer else ''
fSuccess = True
try:
i = 0
j = 0
while fSuccess and i < m and j < n:
if self.Crypto.VerifySignature(message, sigs[i],
pubkeys[j]):
i += 1
j += 1
if m - i > n - j:
fSuccess = False
except Exception as e:
fSuccess = False
estack.PushT(fSuccess)
# lists
elif opcode == ARRAYSIZE:
item = estack.Pop()
if not item:
return self.VM_FAULT_and_report(VMFault.UNKNOWN7)
if isinstance(item, CollectionMixin):
estack.PushT(item.Count)
else:
estack.PushT(len(item.GetByteArray()))
elif opcode == PACK:
size = estack.Pop().GetBigInteger()
if size < 0 or size > estack.Count:
return self.VM_FAULT_and_report(VMFault.UNKNOWN8)
items = []
for i in range(0, size):
topack = estack.Pop()
items.append(topack)
estack.PushT(items)
elif opcode == UNPACK:
item = estack.Pop()
if not isinstance(item, Array):
return self.VM_FAULT_and_report(
VMFault.UNPACK_INVALID_TYPE, item)
items = item.GetArray()
items.reverse()
[estack.PushT(i) for i in items]
estack.PushT(len(items))
elif opcode == PICKITEM:
key = estack.Pop()
if isinstance(key, CollectionMixin):
# key must be an array index or dictionary key, but not a collection
return self.VM_FAULT_and_report(VMFault.KEY_IS_COLLECTION,
key)
collection = estack.Pop()
if isinstance(collection, Array):
index = key.GetBigInteger()
if index < 0 or index >= collection.Count:
return self.VM_FAULT_and_report(
VMFault.PICKITEM_INVALID_INDEX, index,
collection.Count)
items = collection.GetArray()
to_pick = items[index]
estack.PushT(to_pick)
elif isinstance(collection, Map):
success, value = collection.TryGetValue(key)
if success:
estack.PushT(value)
else:
return self.VM_FAULT_and_report(
VMFault.DICT_KEY_NOT_FOUND, key, collection.Keys)
else:
return self.VM_FAULT_and_report(
VMFault.PICKITEM_INVALID_TYPE, key, collection)
elif opcode == SETITEM:
value = estack.Pop()
if isinstance(value, Struct):
value = value.Clone()
key = estack.Pop()
if isinstance(key, CollectionMixin):
return self.VM_FAULT_and_report(VMFault.KEY_IS_COLLECTION)
collection = estack.Pop()
if isinstance(collection, Array):
index = key.GetBigInteger()
if index < 0 or index >= collection.Count:
return self.VM_FAULT_and_report(
VMFault.SETITEM_INVALID_INDEX)
items = collection.GetArray()
items[index] = value
elif isinstance(collection, Map):
collection.SetItem(key, value)
else:
return self.VM_FAULT_and_report(
VMFault.SETITEM_INVALID_TYPE, key, collection)
elif opcode == NEWARRAY:
count = estack.Pop().GetBigInteger()
items = [Boolean(False) for i in range(0, count)]
estack.PushT(Array(items))
elif opcode == NEWSTRUCT:
count = estack.Pop().GetBigInteger()
items = [Boolean(False) for i in range(0, count)]
estack.PushT(Struct(items))
elif opcode == NEWMAP:
estack.PushT(Map())
elif opcode == APPEND:
newItem = estack.Pop()
if isinstance(newItem, Struct):
newItem = newItem.Clone()
arrItem = estack.Pop()
if not isinstance(arrItem, Array):
return self.VM_FAULT_and_report(
VMFault.APPEND_INVALID_TYPE, arrItem)
arr = arrItem.GetArray()
arr.append(newItem)
elif opcode == REVERSE:
arrItem = estack.Pop()
if not isinstance(arrItem, Array):
return self.VM_FAULT_and_report(
VMFault.REVERSE_INVALID_TYPE, arrItem)
arrItem.Reverse()
elif opcode == REMOVE:
key = estack.Pop()
if isinstance(key, CollectionMixin):
return self.VM_FAULT_and_report(VMFault.UNKNOWN1)
collection = estack.Pop()
if isinstance(collection, Array):
index = key.GetBigInteger()
if index < 0 or index >= collection.Count:
return self.VM_FAULT_and_report(
VMFault.REMOVE_INVALID_INDEX, index,
collection.Count)
collection.RemoveAt(index)
elif isinstance(collection, Map):
collection.Remove(key)
else:
return self.VM_FAULT_and_report(
VMFault.REMOVE_INVALID_TYPE, key, collection)
elif opcode == HASKEY:
key = estack.Pop()
if isinstance(key, CollectionMixin):
return self.VM_FAULT_and_report(VMFault.DICT_KEY_ERROR)
collection = estack.Pop()
if isinstance(collection, Array):
index = key.GetBigInteger()
if index < 0:
return self.VM_FAULT_and_report(VMFault.DICT_KEY_ERROR)
estack.PushT(index < collection.Count)
elif isinstance(collection, Map):
estack.PushT(collection.ContainsKey(key))
else:
return self.VM_FAULT_and_report(VMFault.DICT_KEY_ERROR)
elif opcode == KEYS:
collection = estack.Pop()
if isinstance(collection, Map):
estack.PushT(Array(collection.Keys))
else:
return self.VM_FAULT_and_report(VMFault.DICT_KEY_ERROR)
elif opcode == VALUES:
collection = estack.Pop()
values = []
if isinstance(collection, Map):
values = collection.Values
elif isinstance(collection, Array):
values = collection
else:
return self.VM_FAULT_and_report(VMFault.DICT_KEY_ERROR)
newArray = Array()
for item in values:
if isinstance(item, Struct):
newArray.Add(item.Clone())
else:
newArray.Add(item)
estack.PushT(newArray)
elif opcode == THROW:
return self.VM_FAULT_and_report(VMFault.THROW)
elif opcode == THROWIFNOT:
if not estack.Pop().GetBoolean():
return self.VM_FAULT_and_report(VMFault.THROWIFNOT)
else:
return self.VM_FAULT_and_report(VMFault.UNKNOWN_OPCODE, opcode)
if self._VMState & VMState.FAULT == 0 and self.InvocationStack.Count > 0:
if len(self.CurrentContext.Breakpoints):
if self.CurrentContext.InstructionPointer in self.CurrentContext.Breakpoints:
self._vm_debugger = VMDebugger(self)
self._vm_debugger.start()
def LoadScript(self, script, push_only=False):
context = ExecutionContext(self, script, push_only)
if self._debug_map and context.ScriptHash(
) == self._debug_map['script_hash']:
context.Breakpoints = set(self._debug_map['breakpoints'])
self._InvocationStack.PushT(context)
self._ExecutedScriptHashes.append(context.ScriptHash())
def RemoveBreakPoint(self, position):
if self._InvocationStack.Count == 0:
return False
return self.CurrentContext.Breakpoints.remove(position)
def StepInto(self):
if self._InvocationStack.Count == 0:
self._VMState |= VMState.HALT
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
logger.info("stopping because vm state is %s " % self._VMState)
return
op = None
if self.CurrentContext.InstructionPointer >= len(
self.CurrentContext.Script):
op = RET
else:
op = self.CurrentContext.OpReader.ReadByte(do_ord=False)
self.ops_processed += 1
try:
if self._is_write_log:
self.write_log("{} {}".format(self.ops_processed, ToName(op)))
self.ExecuteOp(op, self.CurrentContext)
except Exception as e:
error_msg = "COULD NOT EXECUTE OP (%s): %s %s %s" % (
self.ops_processed, e, op, ToName(op))
self.write_log(error_msg)
if self._exit_on_error:
self._VMState |= VMState.FAULT
else:
logger.error(error_msg)
logger.exception(e)
def StepOut(self):
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
def StepOver(self):
if self._VMState & VMState.HALT > 0 or self._VMState & VMState.FAULT > 0:
return
self._VMState &= ~VMState.BREAK
count = self._InvocationStack.Count
while self._VMState & VMState.HALT == 0 and \
self._VMState & VMState.FAULT == 0 and \
self._VMState & VMState.BREAK == 0 and \
self._InvocationStack.Count > count:
self.StepInto()
def VM_FAULT_and_report(self, id, *args):
self._VMState |= VMState.FAULT
if settings.log_level != LOGGING_LEVEL_DEBUG:
return
if id == VMFault.INVALID_JUMP:
error_msg = "Attemping to JMP/JMPIF/JMPIFNOT to an invalid location."
elif id == VMFault.INVALID_CONTRACT:
script_hash = args[0]
error_msg = "Trying to call an unknown contract with script_hash {}\nMake sure the contract exists on the blockchain".format(
script_hash)
elif id == VMFault.CHECKMULTISIG_INVALID_PUBLICKEY_COUNT:
error_msg = "CHECKMULTISIG - provided public key count is less than 1."
elif id == VMFault.CHECKMULTISIG_SIGNATURE_ERROR:
if args[0] < 1:
error_msg = "CHECKMULTISIG - Minimum required signature count cannot be less than 1."
else: # m > n
m = args[0]
n = args[1]
error_msg = "CHECKMULTISIG - Insufficient signatures provided ({}). Minimum required is {}".format(
m, n)
elif id == VMFault.UNPACK_INVALID_TYPE:
item = args[0]
error_msg = "Failed to UNPACK item. Item is not an array but of type: {}".format(
type(item))
elif id == VMFault.PICKITEM_INVALID_TYPE:
index = args[0]
item = args[1]
error_msg = "Cannot access item at index {}. Item is not an array or dict but of type: {}".format(
index, type(item))
elif id == VMFault.PICKITEM_NEGATIVE_INDEX:
error_msg = "Attempting to access an array using a negative index"
elif id == VMFault.PICKITEM_INVALID_INDEX:
index = args[0]
length = args[1]
error_msg = "Array index is less than zero or {} exceeds list length {}".format(
index, length)
elif id == VMFault.APPEND_INVALID_TYPE:
item = args[0]
error_msg = "Cannot append to item. Item is not an array but of type: {}".format(
type(item))
elif id == VMFault.REVERSE_INVALID_TYPE:
item = args[0]
error_msg = "Cannot REVERSE item. Item is not an array but of type: {}".format(
type(item))
elif id == VMFault.REMOVE_INVALID_TYPE:
item = args[0]
index = args[1]
error_msg = "Cannot REMOVE item at index {}. Item is not an array but of type: {}".format(
index, type(item))
elif id == VMFault.REMOVE_INVALID_INDEX:
index = args[0]
length = args[1]
if index < 0:
error_msg = "Cannot REMOVE item at index {}. Index < 0".format(
index)
else: # index >= len(items):
error_msg = "Cannot REMOVE item at index {}. Index exceeds array length {}".format(
index, length)
elif id == VMFault.POP_ITEM_NOT_ARRAY:
error_msg = "Items(s) not array: %s" % [item for item in args]
elif id == VMFault.UNKNOWN_OPCODE:
opcode = args[0]
error_msg = "Unknown opcode found: {}".format(opcode)
else:
error_msg = id
if id in [VMFault.THROW, VMFault.THROWIFNOT]:
logger.debug("({}) {}".format(self.ops_processed, id))
else:
logger.error("({}) {}".format(self.ops_processed, error_msg))
return