def should_void_transfer(transfer, wallet_view_context: WalletTransferContext,
recipient_view_context: WalletTransferContext,
operator_eon_number, is_checkpoint_created):
if transfer.eon_number != operator_eon_number and is_checkpoint_created:
logger.error('Transfer {} eon mismatch ({}, {})'.format(
transfer.id, transfer.eon_number, operator_eon_number))
return True
if transfer.amount < 0:
logger.error('Transfer {} has negative amount'.format(transfer.id))
return True
# Unauthorized transfer
if transfer.sender_active_state is None:
logger.error('Transfer {} no authorization'.format(transfer.id))
return True
# Invalid signature by sender
if not transfer.sender_active_state.wallet_signature.is_valid():
logger.error('Transfer {} invalid sender signature.'.format(
transfer.id))
return True
# Ensure sender log consistency
can_append_to_sender_log = wallet_view_context.can_append_transfer()
if can_append_to_sender_log is not True:
logger.error('Sender: {}'.format(can_append_to_sender_log))
return True
# Ensure recipient log consistency
can_append_to_recipient_log = recipient_view_context.can_append_transfer()
if can_append_to_recipient_log is not True:
logger.error('Recipient: {}'.format(can_append_to_recipient_log))
return True
# Ensure transfer consistency
can_spend, currently_available_funds = wallet_view_context.can_send_transfer(
current_eon_number=operator_eon_number, using_only_appended_funds=True)
if can_spend is not True:
passively_received = wallet_view_context.off_chain_passively_received_amount(
eon_number=operator_eon_number, only_appended=True)
logger.error(can_spend)
logger.info(passively_received)
return True
last_active_transfer, last_active_transfer_is_outgoing = wallet_view_context.last_appended_active_transfer(
operator_eon_number)
last_active_state = WalletTransferContext.appropriate_transfer_active_state(
transfer=last_active_transfer,
is_outgoing=last_active_transfer_is_outgoing)
previous_spendings = last_active_state.updated_spendings if last_active_transfer else 0
updated_spendings = transfer.sender_active_state.updated_spendings
# Incorrect updated spendings
if last_active_transfer:
if updated_spendings != previous_spendings + transfer.amount:
logger.error(
'Transfer {} invalid updated spendings. Expected {}, found {}.'
.format(transfer.id, previous_spendings + transfer.amount,
updated_spendings))
return True
elif updated_spendings != transfer.amount:
logger.error(
'Transfer {} invalid initial spendings. Expected {}, found {}.'.
format(transfer.id, transfer.amount, updated_spendings))
return True
# Incorrect transfer position
last_passively_received = recipient_view_context.last_appended_incoming_passive_transfer(
operator_eon_number)
if last_passively_received:
if transfer.position != last_passively_received.position + last_passively_received.amount:
logger.error(
'Transfer {} invalid offset. Expected {}, found {}.'.format(
transfer.id, last_passively_received.position +
last_passively_received.amount, transfer.position))
return True
elif transfer.position != 0:
logger.error(
'Transfer {} invalid offset. Expected {}, found {}.'.format(
transfer.id, 0, transfer.position))
return True
if transfer.sender_balance_marker.amount > currently_available_funds - transfer.amount:
logger.error('Transfer {} invalid concise marker balance.'.format(
transfer.id))
return True
concise_balance_marker = MinimumAvailableBalanceMarker(
wallet=transfer.wallet,
eon_number=transfer.eon_number,
amount=transfer.sender_balance_marker.amount)
concise_balance_marker_checksum = hex_value(
concise_balance_marker.checksum())
if transfer.sender_balance_marker.signature.checksum != concise_balance_marker_checksum:
logger.error(
'Transfer {} invalid concise marker checksum worth: {}'.format(
transfer.id, currently_available_funds - transfer.amount))
passively_received = wallet_view_context.off_chain_passively_received_amount(
eon_number=operator_eon_number, only_appended=True)
logger.info(passively_received)
return True
return False
def create(self, validated_data):
active_state_signature_data = validated_data.pop('debit_signature')
wallet = validated_data.pop('wallet')
recipient = validated_data.pop('recipient')
# get current eon
current_eon = LocalViewInterface.latest().eon_number()
# transfer eon should be the current eon number
if validated_data.pop('eon_number') != current_eon:
raise serializers.ValidationError(
detail='', code=ErrorCode.EON_NUMBER_OUT_OF_SYNC)
# TODO refactor this such that the recipient is only locked after the sender's details are verified
wallets = sorted([wallet, recipient], key=lambda w: w.trail_identifier)
with RootCommitment.read_write_lock(
suffix=current_eon, auto_renewal=False), wallets[0].lock(
auto_renewal=False), wallets[1].lock(auto_renewal=False):
if RootCommitment.objects.filter(eon_number=current_eon +
1).exists():
raise serializers.ValidationError(
detail='', code=ErrorCode.EON_NUMBER_OUT_OF_SYNC)
transfer = Transfer(wallet=wallet,
amount=validated_data.pop('amount'),
eon_number=current_eon,
recipient=recipient,
nonce=validated_data.pop('nonce'),
passive=True)
wallet_view_context = WalletTransferContext(wallet=wallet,
transfer=transfer)
recipient_view_context = WalletTransferContext(wallet=recipient,
transfer=transfer)
# Minimal SLA
if not wallet.is_sla_exempt() and not recipient.is_sla_exempt():
if not wallet.has_valid_sla():
sender_transfers_list = wallet_view_context.authorized_transfers_list(
only_appended=False, force_append=True)
if len(sender_transfers_list) > settings.SLA_THRESHOLD:
raise serializers.ValidationError(
detail='',
code=ErrorCode.DEBIT_WALLET_EXCEEDED_SLA)
elif not recipient.has_valid_sla():
recipient_transfers_list = recipient_view_context.authorized_transfers_list(
only_appended=False, force_append=True)
if len(recipient_transfers_list) > settings.SLA_THRESHOLD:
raise serializers.ValidationError(
detail='',
code=ErrorCode.CREDIT_WALLET_EXCEEDED_SLA)
# Ensure sender log consistency
can_append_to_sender_log = wallet_view_context.can_schedule_transfer(
)
if can_append_to_sender_log is not True:
raise serializers.ValidationError(
detail='Sender: {}'.format(can_append_to_sender_log),
code=ErrorCode.DEBIT_WALLET_CANNOT_ADD_TRANSACTION)
# Ensure recipient log consistency
can_append_to_recipient_log = recipient_view_context.can_schedule_transfer(
)
if can_append_to_recipient_log is not True:
raise serializers.ValidationError(
detail='Recipient: {}'.format(can_append_to_recipient_log),
code=ErrorCode.CREDIT_WALLET_CANNOT_ADD_TRANSACTION)
# Ensure transfer consistency
can_spend, currently_available_funds = wallet_view_context.can_send_transfer(
current_eon_number=current_eon,
using_only_appended_funds=False)
if can_spend is not True:
raise serializers.ValidationError(
detail=can_spend, code=ErrorCode.DEBIT_WALLET_OVERSPENDING)
# Validate data
concise_balance_marker_signature_data = validated_data.pop(
'debit_balance_signature')
concise_balance_marker_amount = validated_data.pop('debit_balance')
if concise_balance_marker_amount > currently_available_funds - transfer.amount:
raise serializers.ValidationError(
detail='',
code=ErrorCode.DEBIT_WALLET_BALANCE_MARKER_EXCEED_BALANCE)
concise_balance_marker = MinimumAvailableBalanceMarker(
wallet=wallet,
eon_number=transfer.eon_number,
amount=concise_balance_marker_amount)
concise_balance_marker_checksum = hex_value(
concise_balance_marker.checksum())
concise_balance_marker_signature = Signature(
wallet=transfer.wallet,
checksum=concise_balance_marker_checksum,
value=concise_balance_marker_signature_data.get('value'))
if not concise_balance_marker_signature.is_valid():
raise serializers.ValidationError(
detail='', code=ErrorCode.INVALID_DEBIT_BALANCE_SIGNATURE)
tx_set_tree = wallet_view_context.optimized_authorized_transfers_tree(
)
tx_set_hash = hex_value(tx_set_tree.root_hash())
transfer_index = tx_set_tree.merkle_tree_nonce_map.get(
transfer.nonce)
transfer_proof = tx_set_tree.proof(transfer_index)
highest_spendings, highest_gains = wallet_view_context.off_chain_actively_sent_received_amounts(
eon_number=transfer.eon_number, only_appended=False)
active_state = ActiveState(wallet=wallet,
updated_spendings=highest_spendings +
transfer.amount,
updated_gains=highest_gains,
tx_set_hash=tx_set_hash,
tx_set_proof_hashes=transfer_proof,
tx_set_index=transfer_index,
eon_number=transfer.eon_number)
checksum = hex_value(active_state.checksum())
active_state_signature = Signature(
wallet=transfer.wallet,
checksum=checksum,
value=active_state_signature_data.get('value'))
if not active_state_signature.is_valid():
raise serializers.ValidationError(
detail='', code=ErrorCode.INVALID_DEBIT_SIGNATURE)
transfer.position = recipient_view_context.off_chain_passively_received_amount(
eon_number=transfer.eon_number, only_appended=False)
# locking context covers saving the state as well to make sure checkpoint creation is consistent
with transaction.atomic():
Signature.objects.bulk_create(
[concise_balance_marker_signature, active_state_signature])
concise_balance_marker.signature = concise_balance_marker_signature
concise_balance_marker.save()
active_state.wallet_signature = active_state_signature
active_state.operator_signature = active_state.sign_active_state(
settings.HUB_OWNER_ACCOUNT_ADDRESS,
settings.HUB_OWNER_ACCOUNT_KEY)
active_state.save()
transfer.sender_active_state = active_state
transfer.sender_balance_marker = concise_balance_marker
# cache transfer index in sender active set
transfer.sender_merkle_index = transfer_index
# transfer.sender_merkle_root_cache = tx_set_hash
# cache active set merkle mountains height array and hash array for recipient active set
transfer.sender_merkle_hash_cache, transfer.sender_merkle_height_cache = tx_set_tree.merkle_cache_stacks(
)
transfer.complete = True
transfer.appended = True
transfer.processed = True
transfer.save()
if transfer.appended:
operator_celery.send_task('auditor.tasks.on_transfer_confirmation',
args=[transfer.id])
return transfer