def proc_ripemd160(ext, msg):
OP_GAS = (opcodes.GRIPEMD160BASE +
(utils.ceil32(msg.data.size) // 32) * opcodes.GRIPEMD160WORD)
gas_cost = OP_GAS
if msg.gas < gas_cost:
return 0, 0, []
d = msg.data.extract_all()
o = [0] * 12 + [safe_ord(x) for x in hashlib.new("ripemd160", d).digest()]
return 1, msg.gas - gas_cost, o
def proc_identity(ext, msg):
OP_GAS = opcodes.GIDENTITYBASE + opcodes.GIDENTITYWORD * (
utils.ceil32(msg.data.size) // 32)
gas_cost = OP_GAS
if msg.gas < gas_cost:
return 0, 0, []
o = [0] * msg.data.size
msg.data.extract_copy(o, 0, 0, len(o))
return 1, msg.gas - gas_cost, o
def proc_sha256(ext, msg):
OP_GAS = (opcodes.GSHA256BASE +
(utils.ceil32(msg.data.size) // 32) * opcodes.GSHA256WORD)
gas_cost = OP_GAS
if msg.gas < gas_cost:
return 0, 0, []
d = msg.data.extract_all()
o = [safe_ord(x) for x in hashlib.sha256(d).digest()]
return 1, msg.gas - gas_cost, o
def mem_extend(mem, compustate, op, start, sz):
if sz and start + sz > len(mem):
oldsize = len(mem) // 32
old_totalfee = oldsize * opcodes.GMEMORY + \
oldsize ** 2 // opcodes.GQUADRATICMEMDENOM
newsize = utils.ceil32(start + sz) // 32
new_totalfee = newsize * opcodes.GMEMORY + \
newsize**2 // opcodes.GQUADRATICMEMDENOM
memfee = new_totalfee - old_totalfee
if compustate.gas < memfee:
compustate.gas = 0
return False
compustate.gas -= memfee
m_extend = (newsize - oldsize) * 32
mem.extend(bytearray(m_extend))
return True
def vm_execute(ext, msg, code):
# precompute trace flag
# if we trace vm, we're in slow mode anyway
trace_vm = log_vm_op.is_active("trace")
# Initialize stack, memory, program counter, etc
compustate = Compustate(gas=msg.gas)
stk = compustate.stack
mem = compustate.memory
# Compute
jumpdest_mask, pushcache = preprocess_code(code)
codelen = len(code)
# For tracing purposes
op = None
_prevop = None
steps = 0
while compustate.pc < codelen:
opcode = safe_ord(code[compustate.pc])
# Invalid operation
if opcode not in opcodes.opcodes:
return vm_exception("INVALID OP", opcode=opcode)
op, in_args, out_args, fee = opcodes.opcodes[opcode]
# Apply operation
if trace_vm:
compustate.reset_prev()
compustate.gas -= fee
compustate.pc += 1
# Tracing
if trace_vm:
"""
This diverges from normal logging, as we use the logging namespace
only to decide which features get logged in 'eth.vm.op'
i.e. tracing can not be activated by activating a sub
like 'eth.vm.op.stack'
"""
trace_data = {}
trace_data["stack"] = list(map(to_string, list(compustate.stack)))
if _prevop in (
"MLOAD",
"MSTORE",
"MSTORE8",
"SHA3",
"CALL",
"CALLCODE",
"CREATE",
"CALLDATACOPY",
"CODECOPY",
"EXTCODECOPY",
):
if len(compustate.memory) < 4096:
trace_data["memory"] = "".join(
[encode_hex(ascii_chr(x)) for x in compustate.memory]
)
else:
trace_data["sha3memory"] = encode_hex(
utils.sha3(b"".join([ascii_chr(x) for x in compustate.memory]))
)
if _prevop in ("SSTORE",) or steps == 0:
trace_data["storage"] = ext.log_storage(msg.to)
trace_data["gas"] = to_string(compustate.gas + fee)
trace_data["inst"] = opcode
trace_data["pc"] = to_string(compustate.pc - 1)
if steps == 0:
trace_data["depth"] = msg.depth
trace_data["address"] = msg.to
trace_data["steps"] = steps
trace_data["depth"] = msg.depth
if op[:4] == "PUSH":
trace_data["pushvalue"] = pushcache[compustate.pc - 1]
log_vm_op.trace("vm", op=op, **trace_data)
steps += 1
_prevop = op
# out of gas error
if compustate.gas < 0:
return vm_exception("OUT OF GAS")
# empty stack error
if in_args > len(compustate.stack):
return vm_exception(
"INSUFFICIENT STACK",
op=op,
needed=to_string(in_args),
available=to_string(len(compustate.stack)),
)
# overfull stack error
if len(compustate.stack) - in_args + out_args > 1024:
return vm_exception(
"STACK SIZE LIMIT EXCEEDED",
op=op,
pre_height=to_string(len(compustate.stack)),
)
# Valid operations
# Pushes first because they are very frequent
if 0x60 <= opcode <= 0x7F:
stk.append(pushcache[compustate.pc - 1])
# Move 1 byte forward for 0x60, up to 32 bytes for 0x7f
compustate.pc += opcode - 0x5F
# Arithmetic
elif opcode < 0x10:
if op == "STOP":
return peaceful_exit("STOP", compustate.gas, [])
elif op == "ADD":
stk.append((stk.pop() + stk.pop()) & TT256M1)
elif op == "SUB":
stk.append((stk.pop() - stk.pop()) & TT256M1)
elif op == "MUL":
stk.append((stk.pop() * stk.pop()) & TT256M1)
elif op == "DIV":
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s1 == 0 else s0 // s1)
elif op == "MOD":
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s1 == 0 else s0 % s1)
elif op == "SDIV":
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(
0
if s1 == 0
else (abs(s0) // abs(s1) * (-1 if s0 * s1 < 0 else 1)) & TT256M1
)
elif op == "SMOD":
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(
0
if s1 == 0
else (abs(s0) % abs(s1) * (-1 if s0 < 0 else 1)) & TT256M1
)
elif op == "ADDMOD":
s0, s1, s2 = stk.pop(), stk.pop(), stk.pop()
stk.append((s0 + s1) % s2 if s2 else 0)
elif op == "MULMOD":
s0, s1, s2 = stk.pop(), stk.pop(), stk.pop()
stk.append((s0 * s1) % s2 if s2 else 0)
elif op == "EXP":
base, exponent = stk.pop(), stk.pop()
# fee for exponent is dependent on its bytes
# calc n bytes to represent exponent
nbytes = len(utils.encode_int(exponent))
expfee = nbytes * opcodes.GEXPONENTBYTE
if compustate.gas < expfee:
compustate.gas = 0
return vm_exception("OOG EXPONENT")
compustate.gas -= expfee
stk.append(pow(base, exponent, TT256))
elif op == "SIGNEXTEND":
s0, s1 = stk.pop(), stk.pop()
if s0 <= 31:
testbit = s0 * 8 + 7
if s1 & (1 << testbit):
stk.append(s1 | (TT256 - (1 << testbit)))
else:
stk.append(s1 & ((1 << testbit) - 1))
else:
stk.append(s1)
# Comparisons
elif opcode < 0x20:
if op == "LT":
stk.append(1 if stk.pop() < stk.pop() else 0)
elif op == "GT":
stk.append(1 if stk.pop() > stk.pop() else 0)
elif op == "SLT":
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(1 if s0 < s1 else 0)
elif op == "SGT":
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(1 if s0 > s1 else 0)
elif op == "EQ":
stk.append(1 if stk.pop() == stk.pop() else 0)
elif op == "ISZERO":
stk.append(0 if stk.pop() else 1)
elif op == "AND":
stk.append(stk.pop() & stk.pop())
elif op == "OR":
stk.append(stk.pop() | stk.pop())
elif op == "XOR":
stk.append(stk.pop() ^ stk.pop())
elif op == "NOT":
stk.append(TT256M1 - stk.pop())
elif op == "BYTE":
s0, s1 = stk.pop(), stk.pop()
if s0 >= 32:
stk.append(0)
else:
stk.append((s1 // 256 ** (31 - s0)) % 256)
elif op == "SHL":
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s0 >= 256 else (s1 << s0) & TT256M1)
elif op == "SHR":
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s0 >= 256 else s1 >> s0)
elif op == "SAR":
s0, s1 = stk.pop(), utils.to_signed(stk.pop())
if s0 >= 256:
ret = 0 if s1 >= 0 else TT256M1
else:
ret = (s1 >> s0) & TT256M1
stk.append(ret)
# SHA3 and environment info
elif opcode < 0x40:
if op == "SHA3":
s0, s1 = stk.pop(), stk.pop()
compustate.gas -= opcodes.GSHA3WORD * (utils.ceil32(s1) // 32)
if compustate.gas < 0:
return vm_exception("OOG PAYING FOR SHA3")
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception("OOG EXTENDING MEMORY")
data = bytearray_to_bytestr(mem[s0 : s0 + s1])
stk.append(utils.big_endian_to_int(utils.sha3(data)))
elif op == "ADDRESS":
stk.append(utils.coerce_to_int(msg.to))
elif op == "BALANCE":
addr = utils.coerce_addr_to_hex(stk.pop() % 2 ** 160)
stk.append(ext.get_balance(addr))
elif op == "ORIGIN":
stk.append(utils.coerce_to_int(ext.tx_origin))
elif op == "CALLER":
stk.append(utils.coerce_to_int(msg.sender))
elif op == "CALLVALUE":
stk.append(msg.value)
elif op == "CALLDATALOAD":
stk.append(msg.data.extract32(stk.pop()))
elif op == "CALLDATASIZE":
stk.append(msg.data.size)
elif op == "CALLDATACOPY":
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception("OOG EXTENDING MEMORY")
if not data_copy(compustate, size):
return vm_exception("OOG COPY DATA")
msg.data.extract_copy(mem, mstart, dstart, size)
elif op == "CODESIZE":
stk.append(codelen)
elif op == "CODECOPY":
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception("OOG EXTENDING MEMORY")
if not data_copy(compustate, size):
return vm_exception("OOG COPY DATA")
for i in range(size):
if dstart + i < codelen:
mem[mstart + i] = safe_ord(code[dstart + i])
else:
mem[mstart + i] = 0
elif op == "RETURNDATACOPY":
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception("OOG EXTENDING MEMORY")
if not data_copy(compustate, size):
return vm_exception("OOG COPY DATA")
if dstart + size > len(compustate.last_returned):
return vm_exception("RETURNDATACOPY out of range")
mem[mstart : mstart + size] = compustate.last_returned[
dstart : dstart + size
]
elif op == "RETURNDATASIZE":
stk.append(len(compustate.last_returned))
elif op == "GASPRICE":
stk.append(ext.tx_gasprice)
elif op == "EXTCODESIZE":
addr = utils.coerce_addr_to_hex(stk.pop() % 2 ** 160)
stk.append(len(ext.get_code(addr) or b""))
elif op == "EXTCODECOPY":
addr = utils.coerce_addr_to_hex(stk.pop() % 2 ** 160)
start, s2, size = stk.pop(), stk.pop(), stk.pop()
extcode = ext.get_code(addr) or b""
assert utils.is_string(extcode)
if not mem_extend(mem, compustate, op, start, size):
return vm_exception("OOG EXTENDING MEMORY")
if not data_copy(compustate, size):
return vm_exception("OOG COPY DATA")
for i in range(size):
if s2 + i < len(extcode):
mem[start + i] = safe_ord(extcode[s2 + i])
else:
mem[start + i] = 0
elif op == "EXTCODEHASH":
addr = utils.coerce_addr_to_hex(stk.pop() % 2 ** 160)
if not ext.account_exists(addr):
stk.append(0)
else:
extcode = ext.get_code(addr) or b""
assert utils.is_string(extcode)
stk.append(utils.big_endian_to_int(utils.sha3(extcode)))
# Block info
elif opcode < 0x50:
if op == "BLOCKHASH":
stk.append(utils.big_endian_to_int(ext.block_hash(stk.pop())))
elif op == "COINBASE":
stk.append(utils.big_endian_to_int(ext.block_coinbase))
elif op == "TIMESTAMP":
stk.append(ext.block_timestamp)
elif op == "NUMBER":
stk.append(ext.block_number)
elif op == "DIFFICULTY":
stk.append(ext.block_difficulty)
elif op == "GASLIMIT":
stk.append(ext.block_gas_limit)
# VM state manipulations
elif opcode < 0x60:
if op == "POP":
stk.pop()
elif op == "MLOAD":
s0 = stk.pop()
if not mem_extend(mem, compustate, op, s0, 32):
return vm_exception("OOG EXTENDING MEMORY")
stk.append(utils.bytes_to_int(mem[s0 : s0 + 32]))
elif op == "MSTORE":
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, 32):
return vm_exception("OOG EXTENDING MEMORY")
mem[s0 : s0 + 32] = utils.encode_int32(s1)
elif op == "MSTORE8":
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, 1):
return vm_exception("OOG EXTENDING MEMORY")
mem[s0] = s1 % 256
elif op == "SLOAD":
stk.append(ext.get_storage_data(msg.to, stk.pop()))
elif op == "SSTORE":
s0, s1 = stk.pop(), stk.pop()
if msg.static:
return vm_exception("Cannot SSTORE inside a static context")
if ext.get_storage_data(msg.to, s0):
gascost = opcodes.GSTORAGEMOD if s1 else opcodes.GSTORAGEKILL
refund = 0 if s1 else opcodes.GSTORAGEREFUND
else:
gascost = opcodes.GSTORAGEADD if s1 else opcodes.GSTORAGEMOD
refund = 0
if compustate.gas < gascost:
return vm_exception("OUT OF GAS")
compustate.gas -= gascost
# adds neg gascost as a refund if below zero
ext.add_refund(refund)
ext.set_storage_data(msg.to, s0, s1)
elif op == "JUMP":
compustate.pc = stk.pop()
if compustate.pc >= codelen or not (
(1 << compustate.pc) & jumpdest_mask
):
return vm_exception("BAD JUMPDEST")
elif op == "JUMPI":
s0, s1 = stk.pop(), stk.pop()
if s1:
compustate.pc = s0
if compustate.pc >= codelen or not (
(1 << compustate.pc) & jumpdest_mask
):
return vm_exception("BAD JUMPDEST")
elif op == "PC":
stk.append(compustate.pc - 1)
elif op == "MSIZE":
stk.append(len(mem))
elif op == "GAS":
stk.append(compustate.gas) # AFTER subtracting cost 1
# DUPn (eg. DUP1: a b c -> a b c c, DUP3: a b c -> a b c a)
elif op[:3] == "DUP":
# 0x7f - opcode is a negative number, -1 for 0x80 ... -16 for 0x8f
stk.append(stk[0x7F - opcode])
# SWAPn (eg. SWAP1: a b c d -> a b d c, SWAP3: a b c d -> d b c a)
elif op[:4] == "SWAP":
# 0x8e - opcode is a negative number, -2 for 0x90 ... -17 for 0x9f
temp = stk[0x8E - opcode]
stk[0x8E - opcode] = stk[-1]
stk[-1] = temp
# Logs (aka "events")
elif op[:3] == "LOG":
"""
0xa0 ... 0xa4, 32/64/96/128/160 + len(data) gas
a. Opcodes LOG0...LOG4 are added, takes 2-6 stack arguments
MEMSTART MEMSZ (TOPIC1) (TOPIC2) (TOPIC3) (TOPIC4)
b. Logs are kept track of during tx execution exactly the same way as suicides
(except as an ordered list, not a set).
Each log is in the form [address, [topic1, ... ], data] where:
* address is what the ADDRESS opcode would output
* data is mem[MEMSTART: MEMSTART + MEMSZ]
* topics are as provided by the opcode
c. The ordered list of logs in the transaction are expressed as [log0, log1, ..., logN].
"""
depth = int(op[3:])
mstart, msz = stk.pop(), stk.pop()
topics = [stk.pop() for x in range(depth)]
compustate.gas -= msz * opcodes.GLOGBYTE
if msg.static:
return vm_exception("Cannot LOG inside a static context")
if not mem_extend(mem, compustate, op, mstart, msz):
return vm_exception("OOG EXTENDING MEMORY")
data = bytearray_to_bytestr(mem[mstart : mstart + msz])
ext.log(msg.to, topics, data)
log_log.trace(
"LOG", to=msg.to, topics=topics, data=list(map(utils.safe_ord, data))
)
# Create a new contract
elif op in ("CREATE", "CREATE2"):
salt = None
if op == "CREATE":
value, mstart, msz = stk.pop(), stk.pop(), stk.pop()
else: # CREATE2
value, mstart, msz, salt = stk.pop(), stk.pop(), stk.pop(), stk.pop()
salt = salt.to_bytes(32, byteorder="big")
compustate.gas -= opcodes.GSHA3WORD * ceil(msz / 32)
if not mem_extend(mem, compustate, op, mstart, msz):
return vm_exception("OOG EXTENDING MEMORY")
if msg.static:
return vm_exception("Cannot CREATE inside a static context")
if ext.get_balance(msg.to) >= value and msg.depth < MAX_DEPTH:
cd = CallData(mem, mstart, msz)
ingas = compustate.gas
ingas = all_but_1n(ingas, opcodes.CALL_CHILD_LIMIT_DENOM)
create_msg = Message(
msg.to,
b"",
value,
ingas,
cd,
msg.depth + 1,
# Used for calculating contract address
to_full_shard_key=msg.to_full_shard_key,
transfer_token_id=msg.transfer_token_id,
gas_token_id=msg.gas_token_id,
)
o, gas, data = ext.create(create_msg, salt)
if o:
stk.append(utils.coerce_to_int(data))
compustate.last_returned = bytearray(b"")
else:
stk.append(0)
compustate.last_returned = bytearray(data)
compustate.gas = compustate.gas - ingas + gas
else:
stk.append(0)
compustate.last_returned = bytearray(b"")
# Calls
elif op in ("CALL", "CALLCODE", "DELEGATECALL", "STATICCALL"):
# Pull arguments from the stack
if op in ("CALL", "CALLCODE"):
gas, to, value, meminstart, meminsz, memoutstart, memoutsz = (
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
)
else:
gas, to, meminstart, meminsz, memoutstart, memoutsz = (
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
stk.pop(),
)
value = 0
# Static context prohibition
if msg.static and value > 0 and op == "CALL":
return vm_exception(
"Cannot make a non-zero-value call inside a static context"
)
# Expand memory
if not mem_extend(
mem, compustate, op, meminstart, meminsz
) or not mem_extend(mem, compustate, op, memoutstart, memoutsz):
return vm_exception("OOG EXTENDING MEMORY")
to = utils.int_to_addr(to)
# Extra gas costs based on various factors
extra_gas = 0
# Creating a new account
if op == "CALL" and not ext.account_exists(to) and (value > 0):
extra_gas += opcodes.GCALLNEWACCOUNT
# Value transfer
if value > 0:
extra_gas += opcodes.GCALLVALUETRANSFER
# Compute child gas limit
if compustate.gas < extra_gas:
return vm_exception("OUT OF GAS", needed=extra_gas)
gas = min(
gas,
all_but_1n(compustate.gas - extra_gas, opcodes.CALL_CHILD_LIMIT_DENOM),
)
submsg_gas = gas + opcodes.GSTIPEND * (value > 0)
# Verify that there is sufficient balance and depth
if ext.get_balance(msg.to) < value or msg.depth >= MAX_DEPTH:
compustate.gas -= gas + extra_gas - submsg_gas
stk.append(0)
compustate.last_returned = bytearray(b"")
else:
# Subtract gas from parent
compustate.gas -= gas + extra_gas
assert compustate.gas >= 0
cd = CallData(mem, meminstart, meminsz)
# Generate the message
if op == "CALL":
call_msg = Message(
msg.to,
to,
value,
submsg_gas,
cd,
msg.depth + 1,
# Used for calculating contract address
to_full_shard_key=msg.to_full_shard_key,
code_address=to,
static=msg.static,
transfer_token_id=msg.transfer_token_id,
gas_token_id=msg.gas_token_id,
)
elif op == "DELEGATECALL":
call_msg = Message(
msg.sender,
msg.to,
msg.value,
submsg_gas,
cd,
msg.depth + 1,
# Used for calculating contract address
to_full_shard_key=msg.to_full_shard_key,
code_address=to,
transfers_value=False,
static=msg.static,
transfer_token_id=msg.transfer_token_id,
gas_token_id=msg.gas_token_id,
)
elif op == "STATICCALL":
call_msg = Message(
msg.to,
to,
value,
submsg_gas,
cd,
msg.depth + 1,
# Used for calculating contract address
to_full_shard_key=msg.to_full_shard_key,
code_address=to,
static=True,
transfer_token_id=msg.transfer_token_id,
gas_token_id=msg.gas_token_id,
)
elif op == "CALLCODE":
call_msg = Message(
msg.to,
msg.to,
value,
submsg_gas,
cd,
msg.depth + 1,
# Used for calculating contract address
to_full_shard_key=msg.to_full_shard_key,
code_address=to,
static=msg.static,
transfer_token_id=msg.transfer_token_id,
gas_token_id=msg.gas_token_id,
)
else:
raise Exception("Lolwut")
# Get result
if call_msg.to == PROC_CURRENT_MNT_ID:
msg.token_id_queried = True
result, gas, data = ext.msg(call_msg)
if result == 0:
stk.append(0)
else:
stk.append(1)
# Set output memory
for i in range(min(len(data), memoutsz)):
mem[memoutstart + i] = data[i]
compustate.gas += gas
compustate.last_returned = bytearray(data)
# Return opcode
elif op == "RETURN":
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception("OOG EXTENDING MEMORY")
return peaceful_exit("RETURN", compustate.gas, mem[s0 : s0 + s1])
# Revert opcode (Metropolis)
elif op == "REVERT":
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception("OOG EXTENDING MEMORY")
return revert(compustate.gas, mem[s0 : s0 + s1])
# SUICIDE opcode (also called SELFDESTRUCT)
elif op == "SUICIDE":
if msg.static:
return vm_exception("Cannot SUICIDE inside a static context")
to = utils.encode_int(stk.pop())
to = ((b"\x00" * (32 - len(to))) + to)[12:]
xfer = ext.get_balance(msg.to)
extra_gas = (
(not ext.account_exists(to)) * (xfer > 0) * opcodes.GCALLNEWACCOUNT
)
if not eat_gas(compustate, extra_gas):
return vm_exception("OUT OF GAS")
ext.set_balance(to, ext.get_balance(to) + xfer)
ext.set_balance(msg.to, 0)
ext.add_suicide(msg.to)
log_msg.debug(
"SUICIDING",
addr=utils.checksum_encode(msg.to),
to=utils.checksum_encode(to),
xferring=xfer,
)
return peaceful_exit("SUICIDED", compustate.gas, [])
if trace_vm:
compustate.reset_prev()
return peaceful_exit("CODE OUT OF RANGE", compustate.gas, [])
def data_copy(compustate, size):
return eat_gas(compustate, opcodes.GCOPY * utils.ceil32(size) // 32)
def vm_execute(ext, msg, code):
# precompute trace flag
# if we trace vm, we're in slow mode anyway
trace_vm = log_vm_op.is_active('trace')
# Initialize stack, memory, program counter, etc
compustate = Compustate(gas=msg.gas)
stk = compustate.stack
mem = compustate.memory
# Compute
jumpdest_mask, pushcache = preprocess_code(code)
codelen = len(code)
# For tracing purposes
op = None
_prevop = None
steps = 0
while compustate.pc < codelen:
opcode = safe_ord(code[compustate.pc])
# Invalid operation
if opcode not in opcodes.opcodes:
return vm_exception('INVALID OP', opcode=opcode)
if opcode in opcodes.opcodesMetropolis and not ext.post_metropolis_hardfork(
):
return vm_exception('INVALID OP (not yet enabled)', opcode=opcode)
op, in_args, out_args, fee = opcodes.opcodes[opcode]
# Apply operation
if trace_vm:
compustate.reset_prev()
compustate.gas -= fee
compustate.pc += 1
# Tracing
if trace_vm:
"""
This diverges from normal logging, as we use the logging namespace
only to decide which features get logged in 'eth.vm.op'
i.e. tracing can not be activated by activating a sub
like 'eth.vm.op.stack'
"""
trace_data = {}
trace_data['stack'] = list(map(to_string, list(compustate.stack)))
if _prevop in ('MLOAD', 'MSTORE', 'MSTORE8', 'SHA3', 'CALL',
'CALLCODE', 'CREATE', 'CALLDATACOPY', 'CODECOPY',
'EXTCODECOPY'):
if len(compustate.memory) < 4096:
trace_data['memory'] = \
''.join([encode_hex(ascii_chr(x)) for x
in compustate.memory])
else:
trace_data['sha3memory'] = \
encode_hex(utils.sha3(b''.join([ascii_chr(x) for
x in compustate.memory])))
if _prevop in ('SSTORE', ) or steps == 0:
trace_data['storage'] = ext.log_storage(msg.to)
trace_data['gas'] = to_string(compustate.gas + fee)
trace_data['inst'] = opcode
trace_data['pc'] = to_string(compustate.pc - 1)
if steps == 0:
trace_data['depth'] = msg.depth
trace_data['address'] = msg.to
trace_data['steps'] = steps
trace_data['depth'] = msg.depth
if op[:4] == 'PUSH':
trace_data['pushvalue'] = pushcache[compustate.pc - 1]
log_vm_op.trace('vm', op=op, **trace_data)
steps += 1
_prevop = op
# out of gas error
if compustate.gas < 0:
return vm_exception('OUT OF GAS')
# empty stack error
if in_args > len(compustate.stack):
return vm_exception('INSUFFICIENT STACK',
op=op,
needed=to_string(in_args),
available=to_string(len(compustate.stack)))
# overfull stack error
if len(compustate.stack) - in_args + out_args > 1024:
return vm_exception('STACK SIZE LIMIT EXCEEDED',
op=op,
pre_height=to_string(len(compustate.stack)))
# Valid operations
# Pushes first because they are very frequent
if 0x60 <= opcode <= 0x7f:
stk.append(pushcache[compustate.pc - 1])
# Move 1 byte forward for 0x60, up to 32 bytes for 0x7f
compustate.pc += opcode - 0x5f
# Arithmetic
elif opcode < 0x10:
if op == 'STOP':
return peaceful_exit('STOP', compustate.gas, [])
elif op == 'ADD':
stk.append((stk.pop() + stk.pop()) & TT256M1)
elif op == 'SUB':
stk.append((stk.pop() - stk.pop()) & TT256M1)
elif op == 'MUL':
stk.append((stk.pop() * stk.pop()) & TT256M1)
elif op == 'DIV':
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s1 == 0 else s0 // s1)
elif op == 'MOD':
s0, s1 = stk.pop(), stk.pop()
stk.append(0 if s1 == 0 else s0 % s1)
elif op == 'SDIV':
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(0 if s1 == 0 else (abs(s0) // abs(s1) *
(-1 if s0 * s1 < 0 else 1))
& TT256M1)
elif op == 'SMOD':
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(0 if s1 == 0 else (abs(s0) % abs(s1) *
(-1 if s0 < 0 else 1)) & TT256M1)
elif op == 'ADDMOD':
s0, s1, s2 = stk.pop(), stk.pop(), stk.pop()
stk.append((s0 + s1) % s2 if s2 else 0)
elif op == 'MULMOD':
s0, s1, s2 = stk.pop(), stk.pop(), stk.pop()
stk.append((s0 * s1) % s2 if s2 else 0)
elif op == 'EXP':
base, exponent = stk.pop(), stk.pop()
# fee for exponent is dependent on its bytes
# calc n bytes to represent exponent
nbytes = len(utils.encode_int(exponent))
expfee = nbytes * opcodes.GEXPONENTBYTE
if ext.post_spurious_dragon_hardfork():
expfee += opcodes.EXP_SUPPLEMENTAL_GAS * nbytes
if compustate.gas < expfee:
compustate.gas = 0
return vm_exception('OOG EXPONENT')
compustate.gas -= expfee
stk.append(pow(base, exponent, TT256))
elif op == 'SIGNEXTEND':
s0, s1 = stk.pop(), stk.pop()
if s0 <= 31:
testbit = s0 * 8 + 7
if s1 & (1 << testbit):
stk.append(s1 | (TT256 - (1 << testbit)))
else:
stk.append(s1 & ((1 << testbit) - 1))
else:
stk.append(s1)
# Comparisons
elif opcode < 0x20:
if op == 'LT':
stk.append(1 if stk.pop() < stk.pop() else 0)
elif op == 'GT':
stk.append(1 if stk.pop() > stk.pop() else 0)
elif op == 'SLT':
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(1 if s0 < s1 else 0)
elif op == 'SGT':
s0, s1 = utils.to_signed(stk.pop()), utils.to_signed(stk.pop())
stk.append(1 if s0 > s1 else 0)
elif op == 'EQ':
stk.append(1 if stk.pop() == stk.pop() else 0)
elif op == 'ISZERO':
stk.append(0 if stk.pop() else 1)
elif op == 'AND':
stk.append(stk.pop() & stk.pop())
elif op == 'OR':
stk.append(stk.pop() | stk.pop())
elif op == 'XOR':
stk.append(stk.pop() ^ stk.pop())
elif op == 'NOT':
stk.append(TT256M1 - stk.pop())
elif op == 'BYTE':
s0, s1 = stk.pop(), stk.pop()
if s0 >= 32:
stk.append(0)
else:
stk.append((s1 // 256**(31 - s0)) % 256)
# SHA3 and environment info
elif opcode < 0x40:
if op == 'SHA3':
s0, s1 = stk.pop(), stk.pop()
compustate.gas -= opcodes.GSHA3WORD * (utils.ceil32(s1) // 32)
if compustate.gas < 0:
return vm_exception('OOG PAYING FOR SHA3')
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception('OOG EXTENDING MEMORY')
data = bytearray_to_bytestr(mem[s0:s0 + s1])
stk.append(utils.big_endian_to_int(utils.sha3(data)))
elif op == 'ADDRESS':
stk.append(utils.coerce_to_int(msg.to))
elif op == 'BALANCE':
if ext.post_anti_dos_hardfork():
if not eat_gas(compustate,
opcodes.BALANCE_SUPPLEMENTAL_GAS):
return vm_exception("OUT OF GAS")
addr = utils.coerce_addr_to_hex(stk.pop() % 2**160)
stk.append(ext.get_balance(addr))
elif op == 'ORIGIN':
stk.append(utils.coerce_to_int(ext.tx_origin))
elif op == 'CALLER':
stk.append(utils.coerce_to_int(msg.sender))
elif op == 'CALLVALUE':
stk.append(msg.value)
elif op == 'CALLDATALOAD':
stk.append(msg.data.extract32(stk.pop()))
elif op == 'CALLDATASIZE':
stk.append(msg.data.size)
elif op == 'CALLDATACOPY':
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception('OOG EXTENDING MEMORY')
if not data_copy(compustate, size):
return vm_exception('OOG COPY DATA')
msg.data.extract_copy(mem, mstart, dstart, size)
elif op == 'CODESIZE':
stk.append(codelen)
elif op == 'CODECOPY':
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception('OOG EXTENDING MEMORY')
if not data_copy(compustate, size):
return vm_exception('OOG COPY DATA')
for i in range(size):
if dstart + i < codelen:
mem[mstart + i] = safe_ord(code[dstart + i])
else:
mem[mstart + i] = 0
elif op == 'RETURNDATACOPY':
mstart, dstart, size = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, size):
return vm_exception('OOG EXTENDING MEMORY')
if not data_copy(compustate, size):
return vm_exception('OOG COPY DATA')
if dstart + size > len(compustate.last_returned):
return vm_exception('RETURNDATACOPY out of range')
mem[mstart:mstart +
size] = compustate.last_returned[dstart:dstart + size]
elif op == 'RETURNDATASIZE':
stk.append(len(compustate.last_returned))
elif op == 'GASPRICE':
stk.append(ext.tx_gasprice)
elif op == 'EXTCODESIZE':
if ext.post_anti_dos_hardfork():
if not eat_gas(compustate,
opcodes.EXTCODELOAD_SUPPLEMENTAL_GAS):
return vm_exception("OUT OF GAS")
addr = utils.coerce_addr_to_hex(stk.pop() % 2**160)
stk.append(len(ext.get_code(addr) or b''))
elif op == 'EXTCODECOPY':
if ext.post_anti_dos_hardfork():
if not eat_gas(compustate,
opcodes.EXTCODELOAD_SUPPLEMENTAL_GAS):
return vm_exception("OUT OF GAS")
addr = utils.coerce_addr_to_hex(stk.pop() % 2**160)
start, s2, size = stk.pop(), stk.pop(), stk.pop()
extcode = ext.get_code(addr) or b''
assert utils.is_string(extcode)
if not mem_extend(mem, compustate, op, start, size):
return vm_exception('OOG EXTENDING MEMORY')
if not data_copy(compustate, size):
return vm_exception('OOG COPY DATA')
for i in range(size):
if s2 + i < len(extcode):
mem[start + i] = safe_ord(extcode[s2 + i])
else:
mem[start + i] = 0
# Block info
elif opcode < 0x50:
if op == 'BLOCKHASH':
if ext.post_constantinople_hardfork() and False:
bh_addr = ext.blockhash_store
stk.append(ext.get_storage_data(bh_addr, stk.pop()))
else:
stk.append(
utils.big_endian_to_int(ext.block_hash(stk.pop())))
elif op == 'COINBASE':
stk.append(utils.big_endian_to_int(ext.block_coinbase))
elif op == 'TIMESTAMP':
stk.append(ext.block_timestamp)
elif op == 'NUMBER':
stk.append(ext.block_number)
elif op == 'DIFFICULTY':
stk.append(ext.block_difficulty)
elif op == 'GASLIMIT':
stk.append(ext.block_gas_limit)
# VM state manipulations
elif opcode < 0x60:
if op == 'POP':
stk.pop()
elif op == 'MLOAD':
s0 = stk.pop()
if not mem_extend(mem, compustate, op, s0, 32):
return vm_exception('OOG EXTENDING MEMORY')
stk.append(utils.bytes_to_int(mem[s0:s0 + 32]))
elif op == 'MSTORE':
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, 32):
return vm_exception('OOG EXTENDING MEMORY')
mem[s0:s0 + 32] = utils.encode_int32(s1)
elif op == 'MSTORE8':
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, 1):
return vm_exception('OOG EXTENDING MEMORY')
mem[s0] = s1 % 256
elif op == 'SLOAD':
if ext.post_anti_dos_hardfork():
if not eat_gas(compustate, opcodes.SLOAD_SUPPLEMENTAL_GAS):
return vm_exception("OUT OF GAS")
stk.append(ext.get_storage_data(msg.to, stk.pop()))
elif op == 'SSTORE':
s0, s1 = stk.pop(), stk.pop()
if msg.static:
return vm_exception(
'Cannot SSTORE inside a static context')
if ext.get_storage_data(msg.to, s0):
gascost = opcodes.GSTORAGEMOD if s1 else opcodes.GSTORAGEKILL
refund = 0 if s1 else opcodes.GSTORAGEREFUND
else:
gascost = opcodes.GSTORAGEADD if s1 else opcodes.GSTORAGEMOD
refund = 0
if compustate.gas < gascost:
return vm_exception('OUT OF GAS')
compustate.gas -= gascost
# adds neg gascost as a refund if below zero
ext.add_refund(refund)
ext.set_storage_data(msg.to, s0, s1)
elif op == 'JUMP':
compustate.pc = stk.pop()
if compustate.pc >= codelen or not (
(1 << compustate.pc) & jumpdest_mask):
return vm_exception('BAD JUMPDEST')
elif op == 'JUMPI':
s0, s1 = stk.pop(), stk.pop()
if s1:
compustate.pc = s0
if compustate.pc >= codelen or not (
(1 << compustate.pc) & jumpdest_mask):
return vm_exception('BAD JUMPDEST')
elif op == 'PC':
stk.append(compustate.pc - 1)
elif op == 'MSIZE':
stk.append(len(mem))
elif op == 'GAS':
stk.append(compustate.gas) # AFTER subtracting cost 1
# DUPn (eg. DUP1: a b c -> a b c c, DUP3: a b c -> a b c a)
elif op[:3] == 'DUP':
# 0x7f - opcode is a negative number, -1 for 0x80 ... -16 for 0x8f
stk.append(stk[0x7f - opcode])
# SWAPn (eg. SWAP1: a b c d -> a b d c, SWAP3: a b c d -> d b c a)
elif op[:4] == 'SWAP':
# 0x8e - opcode is a negative number, -2 for 0x90 ... -17 for 0x9f
temp = stk[0x8e - opcode]
stk[0x8e - opcode] = stk[-1]
stk[-1] = temp
# Logs (aka "events")
elif op[:3] == 'LOG':
"""
0xa0 ... 0xa4, 32/64/96/128/160 + len(data) gas
a. Opcodes LOG0...LOG4 are added, takes 2-6 stack arguments
MEMSTART MEMSZ (TOPIC1) (TOPIC2) (TOPIC3) (TOPIC4)
b. Logs are kept track of during tx execution exactly the same way as suicides
(except as an ordered list, not a set).
Each log is in the form [address, [topic1, ... ], data] where:
* address is what the ADDRESS opcode would output
* data is mem[MEMSTART: MEMSTART + MEMSZ]
* topics are as provided by the opcode
c. The ordered list of logs in the transaction are expressed as [log0, log1, ..., logN].
"""
depth = int(op[3:])
mstart, msz = stk.pop(), stk.pop()
topics = [stk.pop() for x in range(depth)]
compustate.gas -= msz * opcodes.GLOGBYTE
if msg.static:
return vm_exception('Cannot LOG inside a static context')
if not mem_extend(mem, compustate, op, mstart, msz):
return vm_exception('OOG EXTENDING MEMORY')
data = bytearray_to_bytestr(mem[mstart:mstart + msz])
ext.log(msg.to, topics, data)
log_log.trace('LOG',
to=msg.to,
topics=topics,
data=list(map(utils.safe_ord, data)))
# print('LOG', msg.to, topics, list(map(ord, data)))
# Create a new contract
elif op == 'CREATE':
value, mstart, msz = stk.pop(), stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, mstart, msz):
return vm_exception('OOG EXTENDING MEMORY')
if msg.static:
return vm_exception('Cannot CREATE inside a static context')
if ext.get_balance(msg.to) >= value and msg.depth < MAX_DEPTH:
cd = CallData(mem, mstart, msz)
ingas = compustate.gas
if ext.post_anti_dos_hardfork():
ingas = all_but_1n(ingas, opcodes.CALL_CHILD_LIMIT_DENOM)
create_msg = Message(msg.to, b'', value, ingas, cd,
msg.depth + 1)
o, gas, data = ext.create(create_msg)
if o:
stk.append(utils.coerce_to_int(data))
compustate.last_returned = bytearray(b'')
else:
stk.append(0)
compustate.last_returned = bytearray(data)
compustate.gas = compustate.gas - ingas + gas
else:
stk.append(0)
compustate.last_returned = bytearray(b'')
# Calls
elif op in ('CALL', 'CALLCODE', 'DELEGATECALL', 'STATICCALL'):
# Pull arguments from the stack
if op in ('CALL', 'CALLCODE'):
gas, to, value, meminstart, meminsz, memoutstart, memoutsz = \
stk.pop(), stk.pop(), stk.pop(), stk.pop(), stk.pop(), stk.pop(), stk.pop()
else:
gas, to, meminstart, meminsz, memoutstart, memoutsz = \
stk.pop(), stk.pop(), stk.pop(), stk.pop(), stk.pop(), stk.pop()
value = 0
# Static context prohibition
if msg.static and value > 0 and op == 'CALL':
return vm_exception(
'Cannot make a non-zero-value call inside a static context'
)
# Expand memory
if not mem_extend(mem, compustate, op, meminstart, meminsz) or \
not mem_extend(mem, compustate, op, memoutstart, memoutsz):
return vm_exception('OOG EXTENDING MEMORY')
to = utils.int_to_addr(to)
# Extra gas costs based on various factors
extra_gas = 0
# Creating a new account
if op == 'CALL' and not ext.account_exists(to) and (
value > 0 or not ext.post_spurious_dragon_hardfork()):
extra_gas += opcodes.GCALLNEWACCOUNT
# Value transfer
if value > 0:
extra_gas += opcodes.GCALLVALUETRANSFER
# Cost increased from 40 to 700 in Tangerine Whistle
if ext.post_anti_dos_hardfork():
extra_gas += opcodes.CALL_SUPPLEMENTAL_GAS
# Compute child gas limit
if ext.post_anti_dos_hardfork():
if compustate.gas < extra_gas:
return vm_exception('OUT OF GAS', needed=extra_gas)
gas = min(
gas,
all_but_1n(compustate.gas - extra_gas,
opcodes.CALL_CHILD_LIMIT_DENOM))
else:
if compustate.gas < gas + extra_gas:
return vm_exception('OUT OF GAS', needed=gas + extra_gas)
submsg_gas = gas + opcodes.GSTIPEND * (value > 0)
# Verify that there is sufficient balance and depth
if ext.get_balance(msg.to) < value or msg.depth >= MAX_DEPTH:
compustate.gas -= (gas + extra_gas - submsg_gas)
stk.append(0)
compustate.last_returned = bytearray(b'')
else:
# Subtract gas from parent
compustate.gas -= (gas + extra_gas)
assert compustate.gas >= 0
cd = CallData(mem, meminstart, meminsz)
# Generate the message
if op == 'CALL':
call_msg = Message(msg.to,
to,
value,
submsg_gas,
cd,
msg.depth + 1,
code_address=to,
static=msg.static)
elif ext.post_homestead_hardfork() and op == 'DELEGATECALL':
call_msg = Message(msg.sender,
msg.to,
msg.value,
submsg_gas,
cd,
msg.depth + 1,
code_address=to,
transfers_value=False,
static=msg.static)
elif ext.post_metropolis_hardfork() and op == 'STATICCALL':
call_msg = Message(msg.to,
to,
value,
submsg_gas,
cd,
msg.depth + 1,
code_address=to,
static=True)
elif op in ('DELEGATECALL', 'STATICCALL'):
return vm_exception('OPCODE %s INACTIVE' % op)
elif op == 'CALLCODE':
call_msg = Message(msg.to,
msg.to,
value,
submsg_gas,
cd,
msg.depth + 1,
code_address=to,
static=msg.static)
else:
raise Exception("Lolwut")
# Get result
result, gas, data = ext.msg(call_msg)
if result == 0:
stk.append(0)
else:
stk.append(1)
# Set output memory
for i in range(min(len(data), memoutsz)):
mem[memoutstart + i] = data[i]
compustate.gas += gas
compustate.last_returned = bytearray(data)
# Return opcode
elif op == 'RETURN':
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception('OOG EXTENDING MEMORY')
return peaceful_exit('RETURN', compustate.gas, mem[s0:s0 + s1])
# Revert opcode (Metropolis)
elif op == 'REVERT':
if not ext.post_metropolis_hardfork():
return vm_exception('Opcode not yet enabled')
s0, s1 = stk.pop(), stk.pop()
if not mem_extend(mem, compustate, op, s0, s1):
return vm_exception('OOG EXTENDING MEMORY')
return revert(compustate.gas, mem[s0:s0 + s1])
# SUICIDE opcode (also called SELFDESTRUCT)
elif op == 'SUICIDE':
if msg.static:
return vm_exception('Cannot SUICIDE inside a static context')
to = utils.encode_int(stk.pop())
to = ((b'\x00' * (32 - len(to))) + to)[12:]
xfer = ext.get_balance(msg.to)
if ext.post_anti_dos_hardfork():
extra_gas = opcodes.SUICIDE_SUPPLEMENTAL_GAS + \
(not ext.account_exists(to)) * (xfer > 0 or not ext.post_spurious_dragon_hardfork()) * \
opcodes.GCALLNEWACCOUNT
if not eat_gas(compustate, extra_gas):
return vm_exception("OUT OF GAS")
ext.set_balance(to, ext.get_balance(to) + xfer)
ext.set_balance(msg.to, 0)
ext.add_suicide(msg.to)
log_msg.debug('SUICIDING',
addr=utils.checksum_encode(msg.to),
to=utils.checksum_encode(to),
xferring=xfer)
return peaceful_exit('SUICIDED', compustate.gas, [])
if trace_vm:
vm_trace(ext, msg, compustate, opcode, pushcache)
if trace_vm:
compustate.reset_prev()
vm_trace(ext, msg, compustate, 0, None)
return peaceful_exit('CODE OUT OF RANGE', compustate.gas, [])
