p2pool/data.py

   1 from __future__ import division
   2
   3 import itertools
   4
   5 from bitcoin import data as bitcoin_data
   6
   7 class CompressedList(bitcoin_data.Type):
   8     def __init__(self, inner):
   9         self.inner = inner
  10
  11     def read(self, file):
  12         values = bitcoin_data.ListType(self.inner).read(file)
  13         if values != sorted(set(values)):
  14             raise ValueError("invalid values")
  15         references = bitcoin_data.ListType(bitcoin_data.VarIntType()).read(file)
  16         return [values[reference] for reference in references]
  17
  18     def write(self, file, item):
  19         values = sorted(set(item))
  20         values_map = dict((value, i) for i, value in enumerate(values))
  21         bitcoin_data.ListType(self.inner).write(file, values)
  22         bitcoin_data.ListType(bitcoin_data.VarIntType()).write(file, [values_map[subitem] for subitem in item])
  23
  24
  25 merkle_branch_type = bitcoin_data.ListType(bitcoin_data.ComposedType([
  26     ('side', bitcoin_data.StructType('<B')), # enum?
  27     ('hash', bitcoin_data.HashType()),
  28 ]))
  29
  30
  31 share_data_type = bitcoin_data.ComposedType([
  32     ('previous_share_hash', bitcoin_data.PossiblyNone(0, bitcoin_data.HashType())),
  33     ('previous_shares_hash', bitcoin_data.HashType()),
  34     ('target2', bitcoin_data.FloatingIntegerType()),
  35     ('nonce', bitcoin_data.VarStrType()),
  36 ])
  37
  38
  39 coinbase_type = bitcoin_data.ComposedType([
  40     ('identifier', bitcoin_data.StructType('<Q')),
  41     ('share_data', share_data_type),
  42 ])
  43
  44 share_info_type = bitcoin_data.ComposedType([
  45     ('share_data', share_data_type),
  46     ('new_script', bitcoin_data.VarStrType()),
  47     ('subsidy', bitcoin_data.StructType('<Q')),
  48 ])
  49
  50
  51 share1a_type = bitcoin_data.ComposedType([
  52     ('header', bitcoin_data.block_header_type), # merkle_header not completely needed
  53     ('share_info', share_info_type),
  54     ('merkle_branch', merkle_branch_type),
  55 ])
  56
  57 share1b_type = bitcoin_data.ComposedType([
  58     ('header', bitcoin_data.block_header_type),
  59     ('share_info', share_info_type),
  60     ('other_txs', bitcoin_data.ListType(bitcoin_data.tx_type)),
  61 ])
  62
  63 shares_type = CompressedList(bitcoin_data.VarStrType())
  64
  65 def calculate_merkle_branch(txs, index):
  66     hash_list = [(bitcoin_data.tx_type.hash256(tx), i == index, []) for i, tx in enumerate(txs)]
  67
  68     while len(hash_list) > 1:
  69         hash_list = [
  70             (
  71                 bitcoin_data.merkle_record_type.hash256(dict(left=left, right=right)),
  72                 left_f or right_f,
  73                 (left_l if left_f else right_l) + [dict(side=1, hash=right) if left_f else dict(side=0, hash=left)],
  74             )
  75             for (left, left_f, left_l), (right, right_f, right_l) in
  76                 zip(hash_list[::2], hash_list[1::2] + [hash_list[::2][-1]])
  77         ]
  78
  79     assert hash_list[0][1]
  80     assert check_merkle_branch(txs[index], hash_list[0][2]) == hash_list[0][0]
  81
  82     return hash_list[0][2]
  83
  84 def check_merkle_branch(tx, branch):
  85     hash_ = bitcoin_data.tx_type.hash256(tx)
  86     for step in branch:
  87         if not step['side']:
  88             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=step['hash'], right=hash_))
  89         else:
  90             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=hash_, right=step['hash']))
  91     return hash_
  92
  93 def gentx_to_share_info(gentx):
  94     return dict(
  95         share_data=coinbase_type.unpack(gentx['tx_ins'][0]['script'])['share_data'],
  96         subsidy=sum(tx_out['value'] for tx_out in gentx['tx_outs']),
  97         new_script=gentx['tx_outs'][-1]['script'],
  98     )
  99
 100 def share_info_to_gentx(share_info, chain, net):
 101     return generate_transaction(
 102         previous_share2=chain.share2s[share_info['share_data']['previous_share_hash']],
 103         nonce=share_info['share_data']['nonce'],
 104         new_script=share_info['new_script'],
 105         subsidy=share_info['subsidy'],
 106         net=net,
 107     )
 108
 109 class Share(object):
 110     def __init__(self, header, share_info, merkle_branch=None, other_txs=None):
 111         if merkle_branch is None and other_txs is None:
 112             raise ValueError('need either merkle_branch or other_txs')
 113         self.header = header
 114         self.share_info = share_info
 115         self.merkle_branch = merkle_branch
 116         self.other_txs = other_txs
 117
 118         self.share_data = self.share_info['share_data']
 119         self.new_script = self.share_info['new_script']
 120         self.subsidy = self.share_info['subsidy']
 121
 122         self.previous_share_hash = self.share_data['previous_share_hash']
 123         self.previous_shares_hash = self.share_data['previous_shares_hash']
 124         self.target2 = self.share_data['target2']
 125
 126         self.hash = bitcoin_data.block_header_type.hash256(header)
 127
 128     @classmethod
 129     def from_block(cls, block):
 130         return cls(block['header'], gentx_to_share_info(block['txs'][0]), other_txs=block['txs'][1:])
 131
 132     @classmethod
 133     def from_share1a(cls, share1a):
 134         return cls(**share1a)
 135
 136     @classmethod
 137     def from_share1b(cls, share1b):
 138         return cls(**share1b)
 139
 140     def as_block(self):
 141         if self.txs is None:
 142             raise ValueError('share does not contain all txs')
 143
 144         return dict(header=self.header, txs=self.txs)
 145
 146     def as_share1(self):
 147         return dict(header=self.header, gentx_info=self.gentx_info)
 148
 149     def check(self, chain, height, previous_share2, net):
 150         if self.chain_id_data != chain.chain_id_data:
 151             raise ValueError('wrong chain')
 152
 153         if self.hash > net.TARGET_MULTIPLIER*bitcoin_data.bits_to_target(self.header['bits']):
 154             raise ValueError('not enough work!')
 155
 156         gentx, shares, merkle_root = gentx_info_to_gentx_shares_and_merkle_root(self.gentx_info, chain, net)
 157
 158         if merkle_root != self.header['merkle_root']:
 159             raise ValueError("gentx doesn't match header")
 160
 161         return Share2(self, shares, height)
 162
 163 class Share2(object):
 164     '''Share with associated data'''
 165
 166     def __init__(self, share, shares, height):
 167         self.share = share
 168         self.shares = shares
 169         self.height = height
 170
 171         self.shared = False
 172
 173     def flag_shared(self):
 174         self.shared = True
 175
 176 def generate_transaction(tracker, previous_share_hash, new_script, subsidy, nonce, block_target, net):
 177     previous_share2 = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
 178     #previous_share2 = chain.shares
 179     #previous_shares
 180     #shares =
 181     #shares = (previous_share2.shares if previous_share2 is not None else [net.SCRIPT]*net.SPREAD)[1:-1] + [new_script, new_script]
 182
 183     chain = list(itertools.islice(tracker.get_chain(previous_share_hash), net.CHAIN_LENGTH))
 184     if len(chain) < 100:
 185         target2 = bitcoin_data.FloatingIntegerType().truncate_to(2**256//2**32 - 1)
 186     else:
 187         attempts_per_second = sum(bitcoin_data.target_to_average_attempts(share.target) for share in itertools.islice(chain, 0, max(0, len(chain) - 1)))//(chain[0].timestamp - chain[-1].timestamp)
 188         pre_target = 2**256*net.SHARE_PERIOD//attempts_per_second
 189         pre_target2 = math.clip(pre_target, (previous_share2.target*9//10, previous_share2.target*11//10))
 190         pre_target3 = math.clip(pre_target2, (0, 2**256//2**32 - 1))
 191         target2 = bitcoin_data.FloatingIntegerType().truncate_to(pre_target3)
 192
 193
 194     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
 195     total_weight = 0
 196
 197     class fake_share(object):
 198         script = new_script
 199         share = dict(target=target2)
 200
 201     dest_weights = {}
 202     for share in itertools.chain([fake_share], itertools.islice(tracker.get_chain(previous_share_hash), net.CHAIN_LENGTH)):
 203         weight = bitcoin_data.target_to_average_attempts(share.share['target'])
 204         weight = max(weight, attempts_to_block - total_weight)
 205
 206         dest_weights[share.script] = dest_weights.get(share.script, 0) + weight
 207         total_weight += weight
 208
 209         if total_weight == attempts_to_block:
 210             break
 211
 212     amounts = dict((script, subsidy*(199*weight)//(200*total_weight)) for (script, weight) in dest_weights.iteritems())
 213     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy*1//200 # prevent fake previous p2pool blocks
 214     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra
 215
 216     dests = sorted(amounts.iterkeys(), key=lambda script: (script == new_script, script))
 217     assert dests[-1] == new_script, dests
 218
 219     previous_shares = [] # XXX
 220
 221     return dict(
 222         version=1,
 223         tx_ins=[dict(
 224             previous_output=None,
 225             sequence=None,
 226             script=coinbase_type.pack(dict(
 227                 identifier=net.IDENTIFIER,
 228                 share_data=dict(
 229                     previous_share_hash=previous_share_hash,
 230                     previous_shares_hash=shares_type.hash256(previous_shares),
 231                     nonce=nonce,
 232                     target2=target2,
 233                 ),
 234             )),
 235         )],
 236         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]],
 237         lock_time=0,
 238     )
 239
 240
 241 class Tracker(object):
 242     def __init__(self):
 243         self.shares = {} # hash -> share
 244         self.reverse_shares = {} # previous_share_hash -> share_hash
 245         self.heads = {} # hash -> (height, tail hash)
 246         self.heads = set()
 247
 248     def add_share(self, share):
 249         if share.hash in self.shares:
 250             return # XXX raise exception?
 251
 252         self.shares[share.hash] = share
 253         self.reverse_shares.setdefault(share.previous_share_hash, set()).add(share.hash)
 254
 255         if self.reverse_shares.get(share.hash, set()):
 256             pass # not a head
 257         else:
 258             self.heads.add(share.hash)
 259             if share.previous_share_hash in self.heads:
 260                 self.heads.remove(share.previous_share_hash)
 261
 262     def get_chain(self, start):
 263         share_hash_to_get = start
 264         while share_hash_to_get in self.shares:
 265             share = self.shares[share_hash_to_get]
 266             yield share
 267             share_hash_to_get = share.previous_share_hash
 268
 269     def get_best_share_hash(self):
 270         if not self.heads:
 271             return None
 272         return max(self.heads, key=self.score_chain)
 273
 274     def score_chain(self, start):
 275         length = len(self.get_chain(start))
 276
 277         score = 0
 278         for share in itertools.islice(self.get_chain(start), self.net.CHAIN_LENGTH):
 279             score += a
 280
 281         return (min(length, 1000), score)
 282
 283 class OkayTracker(Tracker):
 284     def __init__(self):
 285         Tracker.__init__(self)
 286         self.okay_cache = set()
 287     def is_okay(self, start):
 288         '''
 289         Returns:
 290             {'result': 'okay', verified_height: ...} # if share has an okay parent or if share has CHAIN_LENGTH children and CHAIN_LENTH parents that it verified with
 291             {'result': 'needs_parent', 'parent_hash': ...} # if share doesn't have CHAIN_LENGTH parents
 292             {'result': 'needs_share_shares', 'share_hash': ...} # if share has CHAIN_LENGTH children and needs its shares to
 293             {'result': 'not_okay'} # if the share has a not okay parent or if the share has an okay parent and failed validation
 294         '''
 295
 296         length = len
 297         to_end_rev = []
 298         for share in itertools.islice(self.get_chain(start), self.net.CHAIN_LENGTH):
 299             if share in self.okay_cache:
 300                 return validate(share, to_end_rev[::-1])
 301             to_end_rev.append(share)
 302         # picking up last share from for loop, ew
 303         self.okay_cache.add(share)
 304         return validate(share, to_end_rev[::-1])
 305 class Chain(object):
 306     def __init__(self):
 307         pass
 308
 309 def get_chain_descriptor(tracker, start):
 310     for item in tracker.get_chain(self.net.CHAIN_LENGTH):
 311         a
 312     pass
 313
 314 if __name__ == '__main__':
 315     class FakeShare(object):
 316         def __init__(self, hash, previous_share_hash):
 317             self.hash = hash
 318             self.previous_share_hash = previous_share_hash
 319
 320     t = Tracker()
 321
 322     t.add_share(FakeShare(1, 2))
 323     print t.heads
 324     t.add_share(FakeShare(4, 0))
 325     print t.heads
 326     t.add_share(FakeShare(3, 4))
 327     print t.heads
 328
 329 class Mainnet(bitcoin_data.Mainnet):
 330     SHARE_PERIOD = 5 # seconds
 331     CHAIN_LENGTH = 1000 # shares
 332     SPREAD = 10 # blocks
 333     ROOT_BLOCK = 0x6c9cb0589a44808d9a9361266a4ffb9fea2e2cf4d70bb2118b5
 334     SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 335     IDENTIFIER = 0x7452839666e1f8f8
 336     PREFIX = '2d4224bf18c87b87'.decode('hex')
 337     ADDRS_TABLE = 'addrs'
 338     P2P_PORT = 9333
 339
 340 class Testnet(bitcoin_data.Testnet):
 341     SHARE_PERIOD = 5 # seconds
 342     CHAIN_LENGTH = 1000 # shares
 343     SPREAD = 10 # blocks
 344     ROOT_BLOCK = 0xd5070cd4f2987ad2191af71393731a2b143f094f7b84c9e6aa9a6a
 345     SCRIPT = '410403ad3dee8ab3d8a9ce5dd2abfbe7364ccd9413df1d279bf1a207849310465b0956e5904b1155ecd17574778f9949589ebfd4fb33ce837c241474a225cf08d85dac'.decode('hex')
 346     IDENTIFIER = 0x1ae3479e4eb6700a
 347     PREFIX = 'd19778c812754854'.decode('hex')
 348     ADDRS_TABLE = 'addrs_testnet'
 349     P2P_PORT = 19333