p2pool/data.py

   1 from __future__ import division
   2
   3 import itertools
   4 import random
   5
   6 from twisted.python import log
   7
   8 from p2pool.util import math
   9 from p2pool.bitcoin import data as bitcoin_data
  10 from p2pool.util import memoize, expiring_dict
  11
  12 class CompressedList(bitcoin_data.Type):
  13     def __init__(self, inner):
  14         self.inner = inner
  15
  16     def read(self, file):
  17         values, file = bitcoin_data.ListType(self.inner).read(file)
  18         if values != sorted(set(values)):
  19             raise ValueError('invalid values')
  20         references, file = bitcoin_data.ListType(bitcoin_data.VarIntType()).read(file)
  21         return [values[reference] for reference in references], file
  22
  23     def write(self, file, item):
  24         values = sorted(set(item))
  25         values_map = dict((value, i) for i, value in enumerate(values))
  26         file = bitcoin_data.ListType(self.inner).write(file, values)
  27         return bitcoin_data.ListType(bitcoin_data.VarIntType()).write(file, [values_map[subitem] for subitem in item])
  28
  29
  30 merkle_branch_type = bitcoin_data.ListType(bitcoin_data.ComposedType([
  31     ('side', bitcoin_data.StructType('<B')), # enum?
  32     ('hash', bitcoin_data.HashType()),
  33 ]))
  34
  35
  36 share_data_type = bitcoin_data.ComposedType([
  37     ('previous_share_hash', bitcoin_data.PossiblyNone(0, bitcoin_data.HashType())),
  38     ('previous_shares_hash', bitcoin_data.HashType()),
  39     ('target2', bitcoin_data.FloatingIntegerType()),
  40     ('nonce', bitcoin_data.VarStrType()),
  41 ])
  42
  43
  44 coinbase_type = bitcoin_data.ComposedType([
  45     ('identifier', bitcoin_data.FixedStrType(8)),
  46     ('share_data', share_data_type),
  47 ])
  48
  49 share_info_type = bitcoin_data.ComposedType([
  50     ('share_data', share_data_type),
  51     ('new_script', bitcoin_data.VarStrType()),
  52     ('subsidy', bitcoin_data.StructType('<Q')),
  53 ])
  54
  55
  56 share1a_type = bitcoin_data.ComposedType([
  57     ('header', bitcoin_data.block_header_type), # merkle_header not completely needed
  58     ('share_info', share_info_type),
  59     ('merkle_branch', merkle_branch_type),
  60 ])
  61
  62 share1b_type = bitcoin_data.ComposedType([
  63     ('header', bitcoin_data.block_header_type),
  64     ('share_info', share_info_type),
  65     ('other_txs', bitcoin_data.ListType(bitcoin_data.tx_type)),
  66 ])
  67
  68 shares_type = CompressedList(bitcoin_data.VarStrType())
  69
  70 def calculate_merkle_branch(txs, index):
  71     hash_list = [(bitcoin_data.tx_type.hash256(tx), i == index, []) for i, tx in enumerate(txs)]
  72
  73     while len(hash_list) > 1:
  74         hash_list = [
  75             (
  76                 bitcoin_data.merkle_record_type.hash256(dict(left=left, right=right)),
  77                 left_f or right_f,
  78                 (left_l if left_f else right_l) + [dict(side=1, hash=right) if left_f else dict(side=0, hash=left)],
  79             )
  80             for (left, left_f, left_l), (right, right_f, right_l) in
  81                 zip(hash_list[::2], hash_list[1::2] + [hash_list[::2][-1]])
  82         ]
  83
  84     assert hash_list[0][1]
  85     assert check_merkle_branch(txs[index], hash_list[0][2]) == hash_list[0][0]
  86
  87     return hash_list[0][2]
  88
  89 def check_merkle_branch(tx, branch):
  90     hash_ = bitcoin_data.tx_type.hash256(tx)
  91     for step in branch:
  92         if not step['side']:
  93             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=step['hash'], right=hash_))
  94         else:
  95             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=hash_, right=step['hash']))
  96     return hash_
  97
  98 def gentx_to_share_info(gentx):
  99     return dict(
 100         share_data=coinbase_type.unpack(gentx['tx_ins'][0]['script'])['share_data'],
 101         subsidy=sum(tx_out['value'] for tx_out in gentx['tx_outs']),
 102         new_script=gentx['tx_outs'][-1]['script'],
 103     )
 104
 105 def share_info_to_gentx(share_info, block_target, tracker, net):
 106     return generate_transaction(
 107         tracker=tracker,
 108         previous_share_hash=share_info['share_data']['previous_share_hash'],
 109         new_script=share_info['new_script'],
 110         subsidy=share_info['subsidy'],
 111         nonce=share_info['share_data']['nonce'],
 112         block_target=block_target,
 113         net=net,
 114     )
 115
 116 class Share(object):
 117     peer = None
 118     gentx = None
 119
 120     @classmethod
 121     def from_block(cls, block):
 122         return cls(block['header'], gentx_to_share_info(block['txs'][0]), other_txs=block['txs'][1:])
 123
 124     @classmethod
 125     def from_share1a(cls, share1a):
 126         return cls(**share1a)
 127
 128     @classmethod
 129     def from_share1b(cls, share1b):
 130         return cls(**share1b)
 131
 132     def __init__(self, header, share_info, merkle_branch=None, other_txs=None):
 133         if merkle_branch is None and other_txs is None:
 134             raise ValueError('need either merkle_branch or other_txs')
 135         if other_txs is not None:
 136             new_merkle_branch = calculate_merkle_branch([dict(version=0, tx_ins=[], tx_outs=[], lock_time=0)] + other_txs, 0)
 137             if merkle_branch is not None:
 138                 if merke_branch != new_merkle_branch:
 139                     raise ValueError('invalid merkle_branch and other_txs')
 140             merkle_branch = new_merkle_branch
 141
 142         if len(merkle_branch) > 16:
 143             raise ValueError('merkle_branch too long!')
 144
 145         self.header = header
 146         self.share_info = share_info
 147         self.merkle_branch = merkle_branch
 148         self.other_txs = other_txs
 149
 150         self.timestamp = self.header['timestamp']
 151
 152         self.share_data = self.share_info['share_data']
 153         self.new_script = self.share_info['new_script']
 154         self.subsidy = self.share_info['subsidy']
 155
 156         if len(self.new_script) > 100:
 157             raise ValueError('new_script too long!')
 158
 159         self.previous_hash = self.previous_share_hash = self.share_data['previous_share_hash']
 160         self.previous_shares_hash = self.share_data['previous_shares_hash']
 161         self.target2 = self.share_data['target2']
 162         self.nonce = self.share_data['nonce']
 163
 164         if len(self.nonce) > 20:
 165             raise ValueError('nonce too long!')
 166
 167         self.hash = bitcoin_data.block_header_type.hash256(header)
 168
 169         if self.hash > self.target2:
 170             print 'hash', hex(self.hash)
 171             print 'targ', hex(self.target2)
 172             raise ValueError('not enough work!')
 173
 174
 175         self.shared = False
 176
 177     def as_block(self):
 178         if self.other_txs is None:
 179             raise ValueError('share does not contain all txs')
 180
 181         return dict(header=self.header, txs=[self.gentx] + self.other_txs)
 182
 183     def as_share1a(self):
 184         return dict(header=self.header, share_info=self.share_info, merkle_branch=self.merkle_branch)
 185
 186     def as_share1b(self):
 187         return dict(header=self.header, share_info=self.share_info, other_txs=self.other_txs)
 188
 189     def check(self, tracker, net):
 190         import time
 191         if self.previous_share_hash is not None:
 192             if self.header['timestamp'] <= math.median((s.timestamp for s in itertools.islice(tracker.get_chain_to_root(self.previous_share_hash), 11)), use_float=False):
 193                 raise ValueError('share from too far in the past!')
 194
 195         # XXX use adjusted time
 196         if self.header['timestamp'] > time.time() + 2*60*60:
 197             raise ValueError('share from too far in the future!')
 198
 199         gentx = share_info_to_gentx(self.share_info, self.header['target'], tracker, net)
 200
 201         if check_merkle_branch(gentx, self.merkle_branch) != self.header['merkle_root']:
 202             raise ValueError('''gentx doesn't match header via merkle_branch''')
 203
 204         if self.other_txs is not None:
 205             if bitcoin_data.merkle_hash([gentx] + self.other_txs) != self.header['merkle_root']:
 206                 raise ValueError('''gentx doesn't match header via other_txs''')
 207
 208         self.gentx = gentx
 209
 210         return Share2(self)
 211
 212     def flag_shared(self):
 213         self.shared = True
 214
 215     def __repr__(self):
 216         return '<Share %s>' % (' '.join('%s=%r' % (k, v) for k, v in self.__dict__.iteritems()),)
 217
 218 class Share2(object):
 219     '''Share with associated data'''
 220
 221     def __init__(self, share):
 222         self.share = share
 223
 224         self.shared = False
 225
 226     def flag_shared(self):
 227         self.shared = True
 228
 229 def generate_transaction(tracker, previous_share_hash, new_script, subsidy, nonce, block_target, net):
 230     previous_share2 = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
 231     #previous_share2 = chain.shares
 232     #previous_shares
 233     #shares =
 234     #shares = (previous_share2.shares if previous_share2 is not None else [net.SCRIPT]*net.SPREAD)[1:-1] + [new_script, new_script]
 235
 236     lookbehind = 200
 237     chain = list(itertools.islice(tracker.get_chain_to_root(previous_share_hash), lookbehind))
 238     if len(chain) < lookbehind:
 239         target2 = bitcoin_data.FloatingIntegerType().truncate_to(2**256//2**20 - 1)
 240     else:
 241         attempts = sum(bitcoin_data.target_to_average_attempts(share.target2) for share in chain[:-1])
 242         time = chain[0].timestamp - chain[-1].timestamp
 243         if time == 0:
 244             time = 1
 245         attempts_per_second = attempts//time
 246         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1
 247         pre_target2 = math.clip(pre_target, (previous_share2.target2*9//10, previous_share2.target2*11//10))
 248         pre_target3 = math.clip(pre_target2, (0, 2**256//2**20 - 1))
 249         target2 = bitcoin_data.FloatingIntegerType().truncate_to(pre_target3)
 250         print attempts_per_second//1000, 'KHASH'
 251         #print 'TARGET', 2**256//target2, 2**256/pre_target
 252         #print 'ATT', bitcoin_data.target_to_average_attempts(target2)//1000
 253
 254
 255     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
 256     max_weight = net.SPREAD * attempts_to_block
 257     total_weight = 0
 258
 259     class fake_share(object):
 260         pass
 261     fake_share.new_script = new_script
 262     fake_share.target2 = target2
 263
 264     dest_weights = {}
 265     for i, share in enumerate(itertools.chain([fake_share], itertools.islice(tracker.get_chain_to_root(previous_share_hash), net.CHAIN_LENGTH))):
 266         weight = bitcoin_data.target_to_average_attempts(share.target2)
 267         if weight > max_weight - total_weight:
 268             weight = max_weight - total_weight
 269
 270         dest_weights[share.new_script] = dest_weights.get(share.new_script, 0) + weight
 271         total_weight += weight
 272
 273         if total_weight == max_weight:
 274             break
 275
 276     amounts = dict((script, subsidy*(199*weight)//(200*total_weight)) for (script, weight) in dest_weights.iteritems())
 277     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy*1//200
 278     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra
 279
 280     dests = sorted(amounts.iterkeys(), key=lambda script: (script == new_script, script))
 281     assert dests[-1] == new_script
 282
 283     previous_shares = [] # XXX
 284
 285     return dict(
 286         version=1,
 287         tx_ins=[dict(
 288             previous_output=None,
 289             sequence=None,
 290             script=coinbase_type.pack(dict(
 291                 identifier=net.IDENTIFIER,
 292                 share_data=dict(
 293                     previous_share_hash=previous_share_hash,
 294                     previous_shares_hash=shares_type.hash256(previous_shares),
 295                     nonce=nonce,
 296                     target2=target2,
 297                 ),
 298             )),
 299         )],
 300         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]],
 301         lock_time=0,
 302     )
 303
 304
 305
 306 class OkayTracker(bitcoin_data.Tracker):
 307     def __init__(self, net):
 308         bitcoin_data.Tracker.__init__(self)
 309         self.net = net
 310         self.verified = bitcoin_data.Tracker()
 311
 312         self.okay_cache = {} # hash -> height
 313
 314     def attempt_verify(self, share):
 315         height, last = self.get_height_and_last(share.hash)
 316         if height < self.net.CHAIN_LENGTH and last is not None:
 317             raise AssertionError()
 318         if share.hash in self.verified.shares:
 319             return True
 320         try:
 321             share.check(self, self.net)
 322         except:
 323             print
 324             print 'Share check failed:'
 325             log.err()
 326             print
 327             return False
 328         else:
 329             self.verified.add(share)
 330             return True
 331
 332     def think(self, ht):
 333         desired = set()
 334
 335         # O(len(self.heads))
 336         #   make 'unverified heads' set?
 337         # for each overall head, attempt verification
 338         # if it fails, attempt on parent, and repeat
 339         # if no successful verification because of lack of parents, request parent
 340         for head in self.heads:
 341             head_height, last = self.get_height_and_last(head)
 342
 343             for share in itertools.islice(self.get_chain_known(head), None if last is None else max(0, head_height - self.net.CHAIN_LENGTH)):
 344                 if self.attempt_verify(share):
 345                     break
 346             else:
 347                 desired.add((self.shares[random.choice(list(self.reverse_shares[last]))].peer, last))
 348
 349         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 350         for head in list(self.verified.heads):
 351             head_height, last_hash = self.verified.get_height_and_last(head)
 352             last_height, last_last_hash = self.get_height_and_last(last_hash)
 353             # XXX review boundary conditions
 354             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 355             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 356             get = min(want, can)
 357             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 358             for share in itertools.islice(self.get_chain_known(last_hash), get):
 359                 if not self.attempt_verify(share):
 360                     break
 361             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 362                 desired.add((self.verified.shares[random.choice(list(self.verified.reverse_shares[last_hash]))].peer, last_last_hash))
 363
 364         # decide best verified head
 365         best = max(self.verified.heads, key=lambda h: self.score(h, ht)) if self.verified.heads else None
 366
 367         return best, desired
 368
 369     @memoize.memoize_with_backing(expiring_dict.ExpiringDict(5, get_touches=False))
 370     def score(self, share_hash, ht):
 371         head_height, last = self.verified.get_height_and_last(share_hash)
 372         score2 = 0
 373         attempts = 0
 374         max_height = 0
 375         # XXX should only look past a certain share, not at recent ones
 376         share2_hash = self.verified.get_nth_parent_hash(share_hash, min(self.net.CHAIN_LENGTH//2, head_height//2)) if last is not None else share_hash
 377         # XXX this must go in the opposite direction for max_height to make sense
 378         for share in reversed(list(itertools.islice(self.verified.get_chain_known(share2_hash), self.net.CHAIN_LENGTH))):
 379             max_height = max(max_height, ht.get_min_height(share.header['previous_block']))
 380             attempts += bitcoin_data.target_to_average_attempts(share.target2)
 381             this_score = attempts//(ht.get_highest_height() - max_height + 1)
 382             #this_score = -(ht.get_highest_height() - max_height + 1)//attempts
 383             if this_score > score2:
 384                 score2 = this_score
 385         res = (min(head_height, self.net.CHAIN_LENGTH), score2)
 386         print res
 387         return res
 388
 389
 390 class Mainnet(bitcoin_data.Mainnet):
 391     SHARE_PERIOD = 5 # seconds
 392     CHAIN_LENGTH = 24*60*60//5 # shares
 393     SPREAD = 3 # blocks
 394     SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 395     IDENTIFIER = '7452839666e1f8f8'.decode('hex')
 396     PREFIX = '2d4224bf18c87b87'.decode('hex')
 397     ADDRS_TABLE = 'addrs'
 398     P2P_PORT = 9333
 399
 400 class Testnet(bitcoin_data.Testnet):
 401     SHARE_PERIOD = 5 # seconds
 402     CHAIN_LENGTH = 60*60//5 # shares
 403     SPREAD = 3 # blocks
 404     SCRIPT = '410403ad3dee8ab3d8a9ce5dd2abfbe7364ccd9413df1d279bf1a207849310465b0956e5904b1155ecd17574778f9949589ebfd4fb33ce837c241474a225cf08d85dac'.decode('hex')
 405     IDENTIFIER = '1ae3479e4eb6700a'.decode('hex')
 406     PREFIX = 'd19778c812754854'.decode('hex')
 407     ADDRS_TABLE = 'addrs_testnet'
 408     P2P_PORT = 19333