def events_for_close(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: typing.BlockNumber,
):
""" Emits the event for closing the netting channel if the transfer needs
to be settled on-chain.
"""
transfer = target_state.transfer
safe_to_wait, _ = is_safe_to_wait(
transfer.lock.expiration,
channel_state.reveal_timeout,
block_number,
)
secret_known = channel.is_secret_known(
channel_state.partner_state,
transfer.lock.secrethash,
)
if not safe_to_wait and secret_known:
target_state.state = 'waiting_close'
return channel.events_for_close(channel_state, block_number)
return list()
def events_for_onchain_secretreveal(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: BlockNumber,
block_hash: BlockHash,
) -> List[Event]:
""" Emits the event for revealing the secret on-chain if the transfer
can not be settled off-chain.
"""
transfer = target_state.transfer
expiration = transfer.lock.expiration
safe_to_wait = is_safe_to_wait(expiration, channel_state.reveal_timeout, block_number)
secret_known_offchain = channel.is_secret_known_offchain(
channel_state.partner_state, transfer.lock.secrethash
)
has_onchain_reveal_started = target_state.state == TargetTransferState.ONCHAIN_SECRET_REVEAL
if not safe_to_wait and secret_known_offchain and not has_onchain_reveal_started:
target_state.state = TargetTransferState.ONCHAIN_SECRET_REVEAL
secret = channel.get_secret(channel_state.partner_state, transfer.lock.secrethash)
assert secret, "secret should be known at this point"
return secret_registry.events_for_onchain_secretreveal(
channel_state=channel_state,
secret=secret,
expiration=expiration,
block_hash=block_hash,
)
return list()
def handle_block(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: typing.BlockNumber,
):
""" After Raiden learns about a new block this function must be called to
handle expiration of the hash time lock.
"""
transfer = target_state.transfer
events = list()
secret_known = channel.is_secret_known(
channel_state.partner_state,
transfer.lock.secrethash,
)
is_lock_expired = (not secret_known
and block_number > transfer.lock.expiration)
if secret_known:
events = events_for_onchain_secretreveal(
target_state,
channel_state,
block_number,
)
elif is_lock_expired and target_state.state != 'expired':
failed = EventUnlockClaimFailed(
identifier=transfer.payment_identifier,
secrethash=transfer.lock.secrethash,
reason='lock expired',
)
target_state.state = 'expired'
events = [failed]
return TransitionResult(target_state, events)
def handle_block(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: typing.BlockNumber,
pseudo_random_generator: random.Random,
):
""" After Raiden learns about a new block this function must be called to
handle expiration of the hash time lock.
"""
transfer = target_state.transfer
secret_known = channel.is_secret_known(
channel_state.partner_state,
transfer.lock.secrethash,
)
if not secret_known and block_number > transfer.lock.expiration:
if target_state.state != 'expired':
failed = EventUnlockClaimFailed(
identifier=transfer.payment_identifier,
secrethash=transfer.lock.secrethash,
reason='lock expired',
)
target_state.state = 'expired'
events = [failed]
else:
events = list()
elif target_state.state != 'waiting_close': # only emit the close event once
events = events_for_onchain_secretreveal(target_state, channel_state,
block_number)
else:
events = list()
iteration = TransitionResult(target_state, events)
return iteration
def handle_secretreveal(
target_state: TargetTransferState,
state_change: ReceiveSecretReveal,
channel_state: NettingChannelState,
pseudo_random_generator: random.Random,
):
""" Validates and handles a ReceiveSecretReveal state change. """
valid_secret = state_change.secrethash == target_state.transfer.lock.secrethash
waiting_for_secret = target_state.state == 'secret_request'
if valid_secret and waiting_for_secret:
if isinstance(state_change, ReceiveSecretReveal):
channel.register_secret(
channel_state,
state_change.secret,
state_change.secrethash,
)
elif isinstance(state_change, ContractReceiveSecretReveal):
channel.register_onchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
secret_reveal_block_number=state_change.block_number,
)
else:
assert False, 'Got unexpected StateChange'
route = target_state.route
message_identifier = message_identifier_from_prng(
pseudo_random_generator)
target_state.state = 'reveal_secret'
target_state.secret = state_change.secret
recipient = route.node_address
# Send the secret reveal message only once, delivery is guaranteed by
# the transport and not by the state machine
reveal = SendSecretReveal(
recipient=recipient,
channel_identifier=CHANNEL_IDENTIFIER_GLOBAL_QUEUE,
message_identifier=message_identifier,
secret=target_state.secret,
)
iteration = TransitionResult(target_state, [reveal])
else:
# TODO: event for byzantine behavior
iteration = TransitionResult(target_state, list())
return iteration
def handle_offchain_secretreveal(
target_state: TargetTransferState,
state_change: ReceiveSecretReveal,
channel_state: NettingChannelState,
pseudo_random_generator: random.Random,
block_number: BlockNumber,
):
""" Validates and handles a ReceiveSecretReveal state change. """
valid_secret = is_valid_secret_reveal(
state_change=state_change,
transfer_secrethash=target_state.transfer.lock.secrethash,
secret=state_change.secret,
)
has_transfer_expired = channel.transfer_expired(
transfer=target_state.transfer,
affected_channel=channel_state,
block_number=block_number,
)
if valid_secret and not has_transfer_expired:
channel.register_offchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
)
route = target_state.route
message_identifier = message_identifier_from_prng(
pseudo_random_generator)
target_state.state = TargetTransferState.OFFCHAIN_SECRET_REVEAL
target_state.secret = state_change.secret
recipient = route.node_address
reveal = SendSecretReveal(
recipient=recipient,
channel_identifier=CHANNEL_IDENTIFIER_GLOBAL_QUEUE,
message_identifier=message_identifier,
secret=target_state.secret,
)
iteration = TransitionResult(target_state, [reveal])
else:
# TODO: event for byzantine behavior
iteration = TransitionResult(target_state, list())
return iteration
def handle_offchain_secretreveal(
target_state: TargetTransferState,
state_change: ReceiveSecretReveal,
channel_state: NettingChannelState,
pseudo_random_generator: random.Random,
block_number: BlockNumber,
):
""" Validates and handles a ReceiveSecretReveal state change. """
valid_secret = is_valid_secret_reveal(
state_change=state_change,
transfer_secrethash=target_state.transfer.lock.secrethash,
secret=state_change.secret,
)
has_transfer_expired = channel.transfer_expired(
transfer=target_state.transfer,
affected_channel=channel_state,
block_number=block_number,
)
if valid_secret and not has_transfer_expired:
channel.register_offchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
)
route = target_state.route
message_identifier = message_identifier_from_prng(pseudo_random_generator)
target_state.state = TargetTransferState.OFFCHAIN_SECRET_REVEAL
target_state.secret = state_change.secret
recipient = route.node_address
reveal = SendSecretReveal(
recipient=recipient,
channel_identifier=CHANNEL_IDENTIFIER_GLOBAL_QUEUE,
message_identifier=message_identifier,
secret=target_state.secret,
)
iteration = TransitionResult(target_state, [reveal])
else:
# TODO: event for byzantine behavior
iteration = TransitionResult(target_state, list())
return iteration
def handle_block(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: BlockNumber,
block_hash: BlockHash,
) -> TransitionResult[TargetTransferState]:
""" After Raiden learns about a new block this function must be called to
handle expiration of the hash time lock.
"""
transfer = target_state.transfer
events = list()
lock = transfer.lock
secret_known = channel.is_secret_known(
channel_state.partner_state,
lock.secrethash,
)
lock_has_expired, _ = channel.is_lock_expired(
end_state=channel_state.our_state,
lock=lock,
block_number=block_number,
lock_expiration_threshold=channel.get_receiver_expiration_threshold(
lock),
)
if lock_has_expired and target_state.state != 'expired':
failed = EventUnlockClaimFailed(
identifier=transfer.payment_identifier,
secrethash=transfer.lock.secrethash,
reason=f'lock expired',
)
target_state.state = TargetTransferState.EXPIRED
events = [failed]
elif secret_known:
events = events_for_onchain_secretreveal(
target_state=target_state,
channel_state=channel_state,
block_number=block_number,
block_hash=block_hash,
)
return TransitionResult(target_state, events)
def handle_onchain_secretreveal(
target_state: TargetTransferState,
state_change: ContractReceiveSecretReveal,
channel_state: NettingChannelState,
):
""" Validates and handles a ContractReceiveSecretReveal state change. """
valid_secret = state_change.secrethash == target_state.transfer.lock.secrethash
if valid_secret:
channel.register_onchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
secret_reveal_block_number=state_change.block_number,
)
target_state.state = 'reveal_secret'
target_state.secret = state_change.secret
return TransitionResult(target_state, list())
def handle_block(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: typing.BlockNumber,
):
""" After Raiden learns about a new block this function must be called to
handle expiration of the hash time lock.
"""
transfer = target_state.transfer
events = list()
lock = transfer.lock
secret_known = channel.is_secret_known(
channel_state.partner_state,
lock.secrethash,
)
lock_has_expired, _ = channel.is_lock_expired(
end_state=channel_state.our_state,
lock=lock,
block_number=block_number,
lock_expiration_threshold=typing.BlockNumber(
lock.expiration + DEFAULT_NUMBER_OF_BLOCK_CONFIRMATIONS, ),
)
if lock_has_expired and target_state.state != 'expired':
failed = EventUnlockClaimFailed(
identifier=transfer.payment_identifier,
secrethash=transfer.lock.secrethash,
reason=f'lock expired',
)
target_state.state = 'expired'
events = [failed]
elif secret_known:
events = events_for_onchain_secretreveal(
target_state,
channel_state,
block_number,
)
return TransitionResult(target_state, events)
def handle_block(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: BlockNumber,
):
""" After Raiden learns about a new block this function must be called to
handle expiration of the hash time lock.
"""
transfer = target_state.transfer
events = list()
lock = transfer.lock
secret_known = channel.is_secret_known(
channel_state.partner_state,
lock.secrethash,
)
lock_has_expired, _ = channel.is_lock_expired(
end_state=channel_state.our_state,
lock=lock,
block_number=block_number,
lock_expiration_threshold=channel.get_receiver_expiration_threshold(lock),
)
if lock_has_expired and target_state.state != 'expired':
failed = EventUnlockClaimFailed(
identifier=transfer.payment_identifier,
secrethash=transfer.lock.secrethash,
reason=f'lock expired',
)
target_state.state = TargetTransferState.EXPIRED
events = [failed]
elif secret_known:
events = events_for_onchain_secretreveal(
target_state,
channel_state,
block_number,
)
return TransitionResult(target_state, events)
def events_for_onchain_secretreveal(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: BlockNumber,
):
""" Emits the event for revealing the secret on-chain if the transfer
can not be settled off-chain.
"""
transfer = target_state.transfer
expiration = transfer.lock.expiration
safe_to_wait, _ = is_safe_to_wait(
expiration,
channel_state.reveal_timeout,
block_number,
)
secret_known_offchain = channel.is_secret_known_offchain(
channel_state.partner_state,
transfer.lock.secrethash,
)
has_onchain_reveal_started = (
target_state.state == TargetTransferState.ONCHAIN_SECRET_REVEAL
)
if not safe_to_wait and secret_known_offchain and not has_onchain_reveal_started:
target_state.state = TargetTransferState.ONCHAIN_SECRET_REVEAL
secret = channel.get_secret(
channel_state.partner_state,
transfer.lock.secrethash,
)
return secret_registry.events_for_onchain_secretreveal(
channel_state,
secret,
expiration,
)
return list()
def handle_offchain_secretreveal(
target_state: TargetTransferState,
state_change: ReceiveSecretReveal,
channel_state: NettingChannelState,
pseudo_random_generator: random.Random,
):
""" Validates and handles a ReceiveSecretReveal state change. """
valid_secret = state_change.secrethash == target_state.transfer.lock.secrethash
if valid_secret:
channel.register_offchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
)
route = target_state.route
message_identifier = message_identifier_from_prng(
pseudo_random_generator)
target_state.state = 'reveal_secret'
target_state.secret = state_change.secret
recipient = route.node_address
reveal = SendSecretReveal(
recipient=recipient,
channel_identifier=CHANNEL_IDENTIFIER_GLOBAL_QUEUE,
message_identifier=message_identifier,
secret=target_state.secret,
)
iteration = TransitionResult(target_state, [reveal])
else:
# TODO: event for byzantine behavior
iteration = TransitionResult(target_state, list())
return iteration
def events_for_onchain_secretreveal(
target_state: TargetTransferState,
channel_state: NettingChannelState,
block_number: BlockNumber,
):
""" Emits the event for revealing the secret on-chain if the transfer
can not be settled off-chain.
"""
transfer = target_state.transfer
expiration = transfer.lock.expiration
safe_to_wait, _ = is_safe_to_wait(
expiration,
channel_state.reveal_timeout,
block_number,
)
secret_known_offchain = channel.is_secret_known_offchain(
channel_state.partner_state,
transfer.lock.secrethash,
)
has_onchain_reveal_started = (
target_state.state == TargetTransferState.ONCHAIN_SECRET_REVEAL)
if not safe_to_wait and secret_known_offchain and not has_onchain_reveal_started:
target_state.state = TargetTransferState.ONCHAIN_SECRET_REVEAL
secret = channel.get_secret(
channel_state.partner_state,
transfer.lock.secrethash,
)
return secret_registry.events_for_onchain_secretreveal(
channel_state,
secret,
expiration,
)
return list()
def handle_onchain_secretreveal(
target_state: TargetTransferState,
state_change: ContractReceiveSecretReveal,
channel_state: NettingChannelState,
):
""" Validates and handles a ContractReceiveSecretReveal state change. """
valid_secret = is_valid_secret_reveal(
state_change=state_change,
transfer_secrethash=target_state.transfer.lock.secrethash,
secret=state_change.secret,
)
if valid_secret:
channel.register_onchain_secret(
channel_state=channel_state,
secret=state_change.secret,
secrethash=state_change.secrethash,
secret_reveal_block_number=state_change.block_number,
)
target_state.state = TargetTransferState.ONCHAIN_UNLOCK
target_state.secret = state_change.secret
return TransitionResult(target_state, list())
def handle_offchain_secretreveal_light(
target_state: TargetTransferState,
state_change: ReceiveSecretRevealLight,
channel_state: NettingChannelState,
pseudo_random_generator: random.Random,
block_number: BlockNumber,
) -> TransitionResult[TargetTransferState]:
""" Validates and handles a ReceiveSecretReveal state change. """
valid_secret = is_valid_secret_reveal(
state_change=state_change,
transfer_secrethash=target_state.transfer.lock.secrethash,
secret=state_change.secret,
)
has_transfer_expired = channel.is_transfer_expired(
transfer=target_state.transfer, affected_channel=channel_state, block_number=block_number
)
if valid_secret and not has_transfer_expired:
# TODO mmarcosmartinez7 this cannot be done without LC interaction
# channel.register_offchain_secret(
# channel_state=channel_state,
# secret=state_change.secret,
# secrethash=state_change.secrethash,
# )
route = target_state.route
message_identifier = message_identifier_from_prng(pseudo_random_generator)
target_state.state = TargetTransferState.OFFCHAIN_SECRET_REVEAL
target_state.secret = state_change.secret
recipient = route.node_address
# Store reveal secret 7, create reveal secret 9 and store it for LC signing.
received_reveal_secret = state_change.secret_reveal_message
reveal_secret_to_send_event = SendSecretReveal(
recipient=recipient,
channel_identifier=CHANNEL_IDENTIFIER_GLOBAL_QUEUE,
message_identifier=message_identifier,
secret=target_state.secret,
)
reveal_secret_to_send_msg = message_from_sendevent(reveal_secret_to_send_event)
store_received_reveal = StoreMessageEvent(
received_reveal_secret.message_identifier,
target_state.transfer.payment_identifier,
7,
received_reveal_secret,
True
)
store_reveal_to_send = StoreMessageEvent(
message_identifier,
target_state.transfer.payment_identifier,
9,
reveal_secret_to_send_msg,
False
)
iteration = TransitionResult(target_state, [store_received_reveal, store_reveal_to_send])
else:
# TODO: event for byzantine behavior
iteration = TransitionResult(target_state, list())
return iteration
