def check_authorities_and_deposit( self, token_dict: Dict[bytes, TokenInfo]) -> None: """Verify that the sum of outputs is equal of the sum of inputs, for each token. If sum of inputs and outputs is not 0, make sure inputs have mint/melt authority. token_dict sums up all tokens present in the tx and their properties (amount, can_mint, can_melt) amount = outputs - inputs, thus: - amount < 0 when melting - amount > 0 when minting :raises InputOutputMismatch: if sum of inputs is not equal to outputs and there's no mint/melt """ withdraw = 0 deposit = 0 for token_uid, token_info in token_dict.items(): if token_uid == settings.HATHOR_TOKEN_UID: continue if token_info.amount == 0: # that's the usual behavior, nothing to do pass elif token_info.amount < 0: # tokens have been melted if not token_info.can_melt: raise InputOutputMismatch( '{} {} tokens melted, but there is no melt authority input' .format(token_info.amount, token_uid.hex())) withdraw += get_withdraw_amount(token_info.amount) else: # tokens have been minted if not token_info.can_mint: raise InputOutputMismatch( '{} {} tokens minted, but there is no mint authority input' .format((-1) * token_info.amount, token_uid.hex())) deposit += get_deposit_amount(token_info.amount) # check whether the deposit/withdraw amount is correct htr_expected_amount = withdraw - deposit htr_info = token_dict[settings.HATHOR_TOKEN_UID] if htr_info.amount != htr_expected_amount: raise InputOutputMismatch( 'HTR balance is different than expected. (amount={}, expected={})' .format( htr_info.amount, htr_expected_amount, ))
def test_token_melt(self): wallet = self.manager.wallet tx = create_tokens(self.manager, self.address_b58) token_uid = tx.tokens[0] parents = self.manager.get_new_tx_parents() script = P2PKH.create_output_script(self.address) # melt tokens and transfer melt authority melt_amount = 100 new_amount = tx.outputs[0].value - melt_amount withdraw_amount = get_withdraw_amount(melt_amount) _input1 = TxInput(tx.hash, 0, b'') _input2 = TxInput(tx.hash, 2, b'') token_output1 = TxOutput(new_amount, script, 1) token_output2 = TxOutput(TxOutput.TOKEN_MELT_MASK, script, 0b10000001) withdraw_output = TxOutput(withdraw_amount, script, 0) tx2 = Transaction( weight=1, inputs=[_input1, _input2], outputs=[token_output1, token_output2, withdraw_output], parents=parents, tokens=[token_uid], storage=self.manager.tx_storage, timestamp=int(self.clock.seconds())) data_to_sign = tx2.get_sighash_all() public_bytes, signature = wallet.get_input_aux_data( data_to_sign, wallet.get_private_key(self.address_b58)) data = P2PKH.create_input_data(public_bytes, signature) tx2.inputs[0].data = data tx2.inputs[1].data = data tx2.resolve() tx2.verify() self.manager.propagate_tx(tx2) self.run_to_completion() # check tokens index tokens_index = self.manager.tx_storage.indexes.tokens.get_token_info( token_uid) mint = list(tokens_index.iter_mint_utxos()) melt = list(tokens_index.iter_melt_utxos()) self.assertIn(TokenUtxoInfo(tx.hash, 1), mint) self.assertIn(TokenUtxoInfo(tx2.hash, 1), melt) # there should only be one element on the indexes for the token self.assertEqual(1, len(mint)) self.assertEqual(1, len(melt)) # check total amount of tokens self.assertEqual(new_amount, tokens_index.get_total()) # melt tokens and withdraw more than what's allowed melt_amount = 100 withdraw_amount = get_withdraw_amount(melt_amount) _input1 = TxInput(tx.hash, 0, b'') _input2 = TxInput(tx.hash, 2, b'') token_output1 = TxOutput(tx.outputs[0].value - melt_amount, script, 1) token_output2 = TxOutput(TxOutput.TOKEN_MELT_MASK, script, 0b10000001) withdraw_output = TxOutput(withdraw_amount + 1, script, 0) tx3 = Transaction( weight=1, inputs=[_input1, _input2], outputs=[token_output1, token_output2, withdraw_output], parents=parents, tokens=[token_uid], storage=self.manager.tx_storage, timestamp=int(self.clock.seconds())) data_to_sign = tx3.get_sighash_all() public_bytes, signature = wallet.get_input_aux_data( data_to_sign, wallet.get_private_key(self.address_b58)) data = P2PKH.create_input_data(public_bytes, signature) tx3.inputs[0].data = data tx3.inputs[1].data = data tx3.resolve() with self.assertRaises(InputOutputMismatch): tx3.verify() # try to melt using mint authority UTXO _input1 = TxInput(tx.hash, 0, b'') _input2 = TxInput(tx.hash, 1, b'') token_output = TxOutput(tx.outputs[0].value - 1, script, 1) tx4 = Transaction(weight=1, inputs=[_input1, _input2], outputs=[token_output], parents=parents, tokens=[token_uid], storage=self.manager.tx_storage, timestamp=int(self.clock.seconds())) data_to_sign = tx4.get_sighash_all() public_bytes, signature = wallet.get_input_aux_data( data_to_sign, wallet.get_private_key(self.address_b58)) data = P2PKH.create_input_data(public_bytes, signature) tx4.inputs[0].data = data tx4.inputs[1].data = data tx4.resolve() with self.assertRaises(InputOutputMismatch): tx4.verify()