Files
stacks-puppet-node/blockstack/lib/operations/preorder.py
2016-02-23 15:56:09 -05:00

236 lines
8.5 KiB
Python

#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""
Blockstack
~~~~~
copyright: (c) 2014-2015 by Halfmoon Labs, Inc.
copyright: (c) 2016 by Blockstack.org
This file is part of Blockstack
Blockstack is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Blockstack is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Blockstack. If not, see <http://www.gnu.org/licenses/>.
"""
from pybitcoin import embed_data_in_blockchain, serialize_transaction, \
analyze_private_key, serialize_sign_and_broadcast, make_op_return_script, \
make_pay_to_address_script, b58check_encode, b58check_decode, BlockchainInfoClient, \
hex_hash160, bin_hash160, BitcoinPrivateKey, BitcoinPublicKey, script_hex_to_address, get_unspents, \
make_op_return_outputs
from pybitcoin.transactions.outputs import calculate_change_amount
from utilitybelt import is_hex
from binascii import hexlify, unhexlify
from ..b40 import b40_to_hex, is_b40
from ..config import *
from ..scripts import *
from ..hashing import hash_name
# consensus hash fields (ORDER MATTERS!)
FIELDS = [
'preorder_name_hash', # hash(name,sender,register_addr)
'consensus_hash', # consensus hash at time of send
'sender', # scriptPubKey hex that identifies the principal that issued the preorder
'sender_pubkey', # if sender is a pubkeyhash script, then this is the public key
'address', # address from the sender's scriptPubKey
'block_number', # block number at which this name was preordered for the first time
'op', # blockstack bytestring describing the operation
'txid', # transaction ID
'vtxindex', # the index in the block where the tx occurs
'op_fee', # blockstack fee (sent to burn address)
]
def build(name, script_pubkey, register_addr, consensus_hash, name_hash=None, testset=False):
"""
Takes a name, including the namespace ID (but not the id: scheme), a script_publickey to prove ownership
of the subsequent NAME_REGISTER operation, and the current consensus hash for this block (to prove that the
caller is not on a shorter fork).
Returns a NAME_PREORDER script.
Record format:
0 2 3 23 39
|-----|--|----------------------------------------------|--------------|
magic op hash(name.ns_id,script_pubkey,register_addr) consensus hash
"""
if name_hash is None:
# expect inputs to the hash
if not is_b40( name ) or "+" in name or name.count(".") > 1:
raise Exception("Name '%s' has non-base-38 characters" % name)
# name itself cannot exceed LENGTHS['blockchain_id_name']
if len(NAME_SCHEME) + len(name) > LENGTHS['blockchain_id_name']:
raise Exception("Name '%s' is too long; exceeds %s bytes" % (name, LENGTHS['blockchain_id_name'] - len(NAME_SCHEME)))
name_hash = hash_name(name, script_pubkey, register_addr=register_addr)
script = 'NAME_PREORDER 0x%s 0x%s' % (name_hash, consensus_hash)
hex_script = blockstack_script_to_hex(script)
packaged_script = add_magic_bytes(hex_script, testset=testset)
return packaged_script
def make_outputs( data, inputs, sender_addr, fee, format='bin' ):
"""
Make outputs for a name preorder:
[0] OP_RETURN with the name
[1] address with the NAME_PREORDER sender's address
[2] pay-to-address with the *burn address* with the fee
"""
op_fee = max(fee, DEFAULT_DUST_FEE)
dust_fee = (len(inputs) + 2) * DEFAULT_DUST_FEE + DEFAULT_OP_RETURN_FEE
dust_value = DEFAULT_DUST_FEE
bill = op_fee
return [
# main output
{"script_hex": make_op_return_script(data, format=format),
"value": 0},
# change address (can be subsidy key)
{"script_hex": make_pay_to_address_script(sender_addr),
"value": calculate_change_amount(inputs, bill, dust_fee)},
# burn address
{"script_hex": make_pay_to_address_script(BLOCKSTORE_BURN_ADDRESS),
"value": op_fee}
]
def broadcast(name, private_key, register_addr, consensus_hash, blockchain_client, fee, blockchain_broadcaster=None, subsidy_public_key=None, tx_only=False, testset=False):
"""
Builds and broadcasts a preorder transaction.
@subsidy_public_key: if given, the public part of the subsidy key
"""
if subsidy_public_key is not None:
# subsidizing, and only want the tx
tx_only = True
# sanity check
if subsidy_public_key is None and private_key is None:
raise Exception("Missing both client public and private key")
if blockchain_broadcaster is None:
blockchain_broadcaster = blockchain_client
from_address = None # change address
inputs = None
private_key_obj = None
script_pubkey = None # to be mixed into preorder hash
if subsidy_public_key is not None:
# subsidizing
pubk = BitcoinPublicKey( subsidy_public_key )
from_address = BitcoinPublicKey( subsidy_public_key ).address()
inputs = get_unspents( from_address, blockchain_client )
script_pubkey = get_script_pubkey( subsidy_public_key )
else:
# ordering directly
pubk = BitcoinPrivateKey( private_key ).public_key()
public_key = pubk.to_hex()
script_pubkey = get_script_pubkey( public_key )
# get inputs and from address using private key
private_key_obj, from_address, inputs = analyze_private_key(private_key, blockchain_client)
nulldata = build( name, script_pubkey, register_addr, consensus_hash, testset=testset)
outputs = make_outputs(nulldata, inputs, from_address, fee, format='hex')
if tx_only:
unsigned_tx = serialize_transaction( inputs, outputs )
return {"unsigned_tx": unsigned_tx}
else:
# serialize, sign, and broadcast the tx
response = serialize_sign_and_broadcast(inputs, outputs, private_key_obj, blockchain_broadcaster)
response.update({'data': nulldata})
return response
def parse(bin_payload):
"""
Parse a name preorder.
NOTE: bin_payload *excludes* the leading 3 bytes (magic + op) returned by build.
"""
if len(bin_payload) != LENGTHS['preorder_name_hash'] + LENGTHS['consensus_hash']:
return None
name_hash = hexlify( bin_payload[0:LENGTHS['preorder_name_hash']] )
consensus_hash = hexlify( bin_payload[LENGTHS['preorder_name_hash']:] )
return {
'opcode': 'NAME_PREORDER',
'preorder_name_hash': name_hash,
'consensus_hash': consensus_hash
}
def get_fees( inputs, outputs ):
"""
Given a transaction's outputs, look up its fees:
* the first output must be an OP_RETURN, and it must have a fee of 0.
# the second must be the change address
* the third must be a burn fee to the burn address.
Return (dust fees, operation fees) on success
Return (None, None) on invalid output listing
"""
if len(outputs) != 3:
log.debug("Expected 3 outputs; got %s" % len(outputs))
return (None, None)
# 0: op_return
if not tx_output_is_op_return( outputs[0] ):
log.debug("outputs[0] is not an OP_RETURN")
return (None, None)
if outputs[0]["value"] != 0:
log.debug("outputs[0] has value %s'" % outputs[0]["value"])
return (None, None)
# 1: change address
if script_hex_to_address( outputs[1]["script_hex"] ) is None:
log.error("outputs[1] has no decipherable change address")
return (None, None)
# 2: burn address
addr_hash = script_hex_to_address( outputs[2]["script_hex"] )
if addr_hash is None:
log.error("outputs[2] has no decipherable burn address")
return (None, None)
if addr_hash != BLOCKSTORE_BURN_ADDRESS:
log.error("outputs[2] is not the burn address")
return (None, None)
dust_fee = (len(inputs) + 2) * DEFAULT_DUST_FEE + DEFAULT_OP_RETURN_FEE
op_fee = outputs[2]["value"]
return (dust_fee, op_fee)