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