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.FixedStrType(8)),
  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     @classmethod
 111     def from_block(cls, block):
 112         return cls(block['header'], gentx_to_share_info(block['txs'][0]), other_txs=block['txs'][1:])
 113
 114     @classmethod
 115     def from_share1a(cls, share1a):
 116         return cls(**share1a)
 117
 118     @classmethod
 119     def from_share1b(cls, share1b):
 120         return cls(**share1b)
 121
 122     def __init__(self, header, share_info, merkle_branch=None, other_txs=None):
 123         if merkle_branch is None and other_txs is None:
 124             raise ValueError('need either merkle_branch or other_txs')
 125
 126         self.header = header
 127         self.share_info = share_info
 128         self.merkle_branch = merkle_branch
 129         self.other_txs = other_txs
 130
 131         self.share_data = self.share_info['share_data']
 132         self.new_script = self.share_info['new_script']
 133         self.subsidy = self.share_info['subsidy']
 134
 135         self.previous_share_hash = self.share_data['previous_share_hash']
 136         self.previous_shares_hash = self.share_data['previous_shares_hash']
 137         self.target2 = self.share_data['target2']
 138
 139         self.hash = bitcoin_data.block_header_type.hash256(header)
 140
 141         if self.hash > self.target2:
 142             raise ValueError('not enough work!')
 143
 144     def as_block(self):
 145         if self.txs is None:
 146             raise ValueError('share does not contain all txs')
 147
 148         return dict(header=self.header, txs=self.txs)
 149
 150     def as_share1a(self):
 151         return dict(header=self.header, share_info=self.share_info, merkle_branch=self.merkle_branch)
 152
 153     def as_share1b(self):
 154         return dict(header=self.header, share_info=self.share_info, other_txs=self.other_txs)
 155
 156     def check(self, tracker, net):
 157         gentx = share_info_to_gentx(self.share_info, tracker, net)
 158
 159         if self.merkle_branch is not None:
 160             if check_merkle_branch(gentx, self.merkle_branch) != self.header['merkle_root']:
 161                 raise ValueError("gentx doesn't match header via merkle_branch")
 162
 163         if self.other_txs is not None:
 164             if bitcoin_data.merkle_hash([gentx] + self.other_txs) != self.header['merkle_root']:
 165                 raise ValueError("gentx doesn't match header via other_txs")
 166
 167         return Share2(self)
 168
 169 class Share2(object):
 170     '''Share with associated data'''
 171
 172     def __init__(self, share):
 173         self.share = share
 174
 175         self.shared = False
 176
 177     def flag_shared(self):
 178         self.shared = True
 179
 180 def generate_transaction(tracker, previous_share_hash, new_script, subsidy, nonce, block_target, net):
 181     previous_share2 = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
 182     #previous_share2 = chain.shares
 183     #previous_shares
 184     #shares =
 185     #shares = (previous_share2.shares if previous_share2 is not None else [net.SCRIPT]*net.SPREAD)[1:-1] + [new_script, new_script]
 186
 187     chain = list(itertools.islice(tracker.get_chain(previous_share_hash), net.CHAIN_LENGTH))
 188     if len(chain) < 100:
 189         target2 = bitcoin_data.FloatingIntegerType().truncate_to(2**256//2**32 - 1)
 190     else:
 191         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)
 192         pre_target = 2**256*net.SHARE_PERIOD//attempts_per_second
 193         pre_target2 = math.clip(pre_target, (previous_share2.target*9//10, previous_share2.target*11//10))
 194         pre_target3 = math.clip(pre_target2, (0, 2**256//2**32 - 1))
 195         target2 = bitcoin_data.FloatingIntegerType().truncate_to(pre_target3)
 196
 197
 198     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
 199     total_weight = 0
 200
 201     class fake_share(object):
 202         script = new_script
 203         share = dict(target=target2)
 204
 205     dest_weights = {}
 206     for i, share in enumerate(itertools.chain([fake_share], itertools.islice(tracker.get_chain(previous_share_hash), net.CHAIN_LENGTH))):
 207         weight = bitcoin_data.target_to_average_attempts(share.share['target'])
 208         weight = max(weight, attempts_to_block - total_weight)
 209
 210         dest_weights[share.script] = dest_weights.get(share.script, 0) + weight
 211         total_weight += weight
 212
 213         if total_weight == attempts_to_block:
 214             break
 215     assert total_weight == attempts_to_block or i == net.CHAIN_LENGTH + 1
 216
 217     amounts = dict((script, subsidy*(199*weight)//(200*total_weight)) for (script, weight) in dest_weights.iteritems())
 218     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy*1//200 # prevent fake previous p2pool blocks
 219     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra
 220
 221     dests = sorted(amounts.iterkeys(), key=lambda script: (script == new_script, script))
 222     assert dests[-1] == new_script
 223
 224     previous_shares = [] # XXX
 225
 226     return dict(
 227         version=1,
 228         tx_ins=[dict(
 229             previous_output=None,
 230             sequence=None,
 231             script=coinbase_type.pack(dict(
 232                 identifier=net.IDENTIFIER,
 233                 share_data=dict(
 234                     previous_share_hash=previous_share_hash,
 235                     previous_shares_hash=shares_type.hash256(previous_shares),
 236                     nonce=nonce,
 237                     target2=target2,
 238                 ),
 239             )),
 240         )],
 241         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]],
 242         lock_time=0,
 243     )
 244
 245
 246 class Tracker(object):
 247     def __init__(self, net):
 248         self.net = net
 249
 250         self.shares = {} # hash -> share
 251         self.reverse_shares = {} # previous_share_hash -> share_hash
 252
 253         self.heads = {} # head hash -> tail_hash
 254         self.tails = {} # tail hash -> set of head hashes
 255         self.heights = {} # share_hash -> height_to, other_share_hash
 256
 257     def add_share(self, share):
 258         if share.hash in self.shares:
 259             return # XXX raise exception?
 260
 261         self.shares[share.hash] = share
 262         self.reverse_shares.setdefault(share.previous_share_hash, set()).add(share.hash)
 263
 264         if share.hash in self.tails:
 265             heads = self.tails.pop(share.hash)
 266         else:
 267             heads = set([share.hash])
 268
 269         if share.previous_share_hash in self.heads:
 270             tail = self.heads.pop(share.previous_share_hash)
 271         else:
 272             tail = share.previous_share_hash
 273
 274         self.tails.setdefault(tail, set()).update(heads)
 275         if share.previous_share_hash in self.tails[tail]:
 276             self.tails[tail].remove(share.previous_share_hash)
 277
 278         for head in heads:
 279             self.heads[head] = tail
 280
 281     def get_height_and_last(self, share_hash):
 282         height = 0
 283         updates = []
 284         while True:
 285             if share_hash is None or share_hash not in self.shares:
 286                 break
 287             updates.append((share_hash, height))
 288             if share_hash in self.heights:
 289                 height_inc, share_hash = self.heights[share_hash]
 290             else:
 291                 height_inc, share_hash = 1, self.shares[share_hash].previous_share_hash
 292             height += height_inc
 293         for update_hash, height_then in updates:
 294             self.heights[update_hash] = height - height_then, share_hash
 295         return height, share_hash
 296
 297     def get_chain(self, start):
 298         share_hash_to_get = start
 299         while share_hash_to_get in self.shares:
 300             share = self.shares[share_hash_to_get]
 301             yield share
 302             share_hash_to_get = share.previous_share_hash
 303
 304     '''
 305     def get_best_share_hash(self):
 306         return max(self.heads, key=self.score_chain)
 307
 308     def score_chain(self, start):
 309         length = len(self.get_chain(start))
 310
 311         score = 0
 312         for share in itertools.islice(self.get_chain(start), self.net.CHAIN_LENGTH):
 313             score += a
 314
 315         return (min(length, 1000), score)
 316     '''
 317
 318 if __name__ == '__main__':
 319     class FakeShare(object):
 320         def __init__(self, hash, previous_share_hash):
 321             self.hash = hash
 322             self.previous_share_hash = previous_share_hash
 323
 324     t = Tracker()
 325
 326     t.add_share(FakeShare(1, 2))
 327     print t.heads, t.tails
 328     t.add_share(FakeShare(4, 0))
 329     print t.heads, t.tails
 330     t.add_share(FakeShare(3, 4))
 331     print t.heads, t.tails
 332     t.add_share(FakeShare(5, 0))
 333     print t.heads, t.tails
 334     t.add_share(FakeShare(0, 1))
 335     print t.heads, t.tails
 336
 337     for share_hash in t.shares:
 338         print share_hash, t.get_height_and_last(share_hash)
 339
 340 class OkayTracker(Tracker):
 341     def __init__(self, net):
 342         Tracker.__init__(self, net)
 343     """
 344         self.okay_cache = {} # hash -> height
 345
 346     def is_okay(self, start, _height_after=0):
 347         '''
 348         Returns:
 349             {'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
 350             {'result': 'needs_share', 'share_hash': ...} # if share doesn't have CHAIN_LENGTH parents
 351             #{'result': 'needs_share_shares', 'share_hash': ...} # if share has CHAIN_LENGTH children and needs its shares to
 352             {'result': 'not_okay'} # if the share has a not okay parent or if the share has an okay parent and failed validation
 353         '''
 354
 355         if start in self.okay_cache:
 356             return dict(result='okay', verified_height=self.okay_cache['start'])
 357
 358         share = self.shares[start]
 359         if start not in self.shares:
 360             return dict(result='needs_share', share_hash=start)
 361
 362         length = len
 363         to_end_rev = []
 364         for share in itertools.islice(self.get_chain(start), self.net.CHAIN_LENGTH):
 365             if share in self.okay_cache:
 366                 return validate(share, to_end_rev[::-1])
 367             to_end_rev.append(share)
 368         # picking up last share from for loop, ew
 369         self.okay_cache.add(share)
 370         return validate(share, to_end_rev[::-1])
 371     """
 372     def think(self):
 373         desired = set()
 374         for head in self.heads:
 375             height, last = self.get_height(head)
 376             if last is not None and height < 2*self.net.CHAIN_LENGTH:
 377                 desired.add(last)
 378                 continue
 379             first_to_verify = math.nth(self.get_chain(head), self.net.CHAIN_LENGTH - 1)
 380             to_verify = []
 381             for share_hash in self.get_chain(head):
 382                 if share_hash not in self.verified:
 383                     to_verify.append(share_hash)
 384             for share_hash in reversed(to_verify):
 385                 try:
 386                     share.check(self, self.net)
 387                 except:
 388                     print
 389                     print "Share check failed:"
 390                     traceback.print_exc()
 391                     print
 392                     break
 393             else:
 394                 a
 395         return desired
 396
 397 class Chain(object):
 398     def __init__(self):
 399         pass
 400
 401 def get_chain_descriptor(tracker, start):
 402     for item in tracker.get_chain(self.net.CHAIN_LENGTH):
 403         a
 404     pass
 405
 406
 407 class Mainnet(bitcoin_data.Mainnet):
 408     SHARE_PERIOD = 5 # seconds
 409     CHAIN_LENGTH = 24*60*60//5 # shares
 410     SPREAD = 3 # blocks
 411     SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 412     IDENTIFIER = '7452839666e1f8f8'.decode('hex')
 413     PREFIX = '2d4224bf18c87b87'.decode('hex')
 414     ADDRS_TABLE = 'addrs'
 415     P2P_PORT = 9333
 416
 417 class Testnet(bitcoin_data.Testnet):
 418     SHARE_PERIOD = 5 # seconds
 419     CHAIN_LENGTH = 24*60*60//5 # shares
 420     SPREAD = 3 # blocks
 421     SCRIPT = '410403ad3dee8ab3d8a9ce5dd2abfbe7364ccd9413df1d279bf1a207849310465b0956e5904b1155ecd17574778f9949589ebfd4fb33ce837c241474a225cf08d85dac'.decode('hex')
 422     IDENTIFIER = '1ae3479e4eb6700a'.decode('hex')
 423     PREFIX = 'd19778c812754854'.decode('hex')
 424     ADDRS_TABLE = 'addrs_testnet'
 425     P2P_PORT = 19333