p2pool/data.py

   1 from __future__ import division
   2
   3 TRANSITION_TIME = 1322804365
   4
   5 import itertools
   6 import random
   7 import time
   8 import os
   9 import struct
  10
  11 from twisted.python import log
  12
  13 import p2pool
  14 from p2pool import skiplists
  15 from p2pool.bitcoin import data as bitcoin_data, script, networks
  16 from p2pool.util import memoize, expiring_dict, math
  17
  18
  19 new_share_data_type = bitcoin_data.ComposedType([
  20     ('previous_share_hash', bitcoin_data.PossiblyNoneType(0, bitcoin_data.HashType())),
  21     ('coinbase', bitcoin_data.VarStrType()),
  22     ('nonce', bitcoin_data.VarStrType()),
  23     ('new_script', bitcoin_data.VarStrType()),
  24     ('subsidy', bitcoin_data.StructType('<Q')),
  25     ('donation', bitcoin_data.StructType('<H')),
  26     ('stale_frac', bitcoin_data.StructType('<B')),
  27 ])
  28
  29 new_share_info_type = bitcoin_data.ComposedType([
  30     ('new_share_data', new_share_data_type),
  31     ('target', bitcoin_data.FloatingIntegerType()),
  32     ('timestamp', bitcoin_data.StructType('<I')),
  33 ])
  34
  35 new_share1a_type = bitcoin_data.ComposedType([
  36     ('header', bitcoin_data.block_header_type),
  37     ('share_info', new_share_info_type),
  38     ('merkle_branch', bitcoin_data.merkle_branch_type),
  39 ])
  40
  41 new_share1b_type = bitcoin_data.ComposedType([
  42     ('header', bitcoin_data.block_header_type),
  43     ('share_info', new_share_info_type),
  44     ('other_txs', bitcoin_data.ListType(bitcoin_data.tx_type)),
  45 ])
  46
  47 # type:
  48 # 0: new_share1a
  49 # 1: new_share1b
  50
  51 new_share_type = bitcoin_data.ComposedType([
  52     ('type', bitcoin_data.VarIntType()),
  53     ('contents', bitcoin_data.VarStrType()),
  54 ])
  55
  56 class NewShare(object):
  57     @classmethod
  58     def from_share1a(cls, share1a, net):
  59         return cls(net, **share1a)
  60
  61     @classmethod
  62     def from_share1b(cls, share1b, net):
  63         return cls(net, **share1b)
  64
  65     def as_share1a(self):
  66         return dict(header=self.header, share_info=self.share_info, merkle_branch=self.merkle_branch)
  67
  68     def as_share1b(self):
  69         if self.other_txs is None:
  70             raise ValueError('share does not contain all txs')
  71
  72         return dict(header=self.header, share_info=self.share_info, other_txs=self.other_txs)
  73
  74     def __repr__(self):
  75         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
  76
  77     __slots__ = 'header previous_block share_info merkle_branch other_txs timestamp share_data new_script subsidy previous_hash previous_share_hash target nonce pow_hash header_hash hash time_seen peer donation stale_frac'.split(' ')
  78
  79     @classmethod
  80     def from_share(cls, share, net):
  81         if share['type'] == 0:
  82             res = cls.from_share1a(new_share1a_type.unpack(share['contents']), net)
  83             if not (res.pow_hash > res.header['target']):
  84                 raise ValueError('invalid share type')
  85             return res
  86         elif share['type'] == 1:
  87             res = cls.from_share1b(new_share1b_type.unpack(share['contents']), net)
  88             if not (res.pow_hash <= res.header['target']):
  89                 raise ValueError('invalid share type')
  90             return res
  91         else:
  92             raise ValueError('unknown share type: %r' % (share['type'],))
  93
  94     def as_share(self):
  95         if self.pow_hash > self.header['target']: # new_share1a
  96             return dict(type=0, contents=new_share1a_type.pack(self.as_share1a()))
  97         elif self.pow_hash <= self.header['target']: # new_share1b
  98             return dict(type=1, contents=new_share1b_type.pack(self.as_share1b()))
  99         else:
 100             raise AssertionError()
 101
 102     def __init__(self, net, header, share_info, merkle_branch=None, other_txs=None):
 103         if merkle_branch is None and other_txs is None:
 104             raise ValueError('need either merkle_branch or other_txs')
 105         if other_txs is not None:
 106             new_merkle_branch = bitcoin_data.calculate_merkle_branch([dict(version=0, tx_ins=[], tx_outs=[], lock_time=0)] + other_txs, 0)
 107             if merkle_branch is not None:
 108                 if merke_branch != new_merkle_branch:
 109                     raise ValueError('invalid merkle_branch and other_txs')
 110             merkle_branch = new_merkle_branch
 111
 112         if len(merkle_branch) > 16:
 113             raise ValueError('merkle_branch too long!')
 114
 115         self.header = header
 116         self.previous_block = header['previous_block']
 117         self.share_info = share_info
 118         self.merkle_branch = merkle_branch
 119         self.other_txs = other_txs
 120
 121         self.share_data = self.share_info['new_share_data']
 122         self.target = self.share_info['target']
 123         self.timestamp = self.share_info['timestamp']
 124
 125         self.new_script = self.share_data['new_script']
 126         self.subsidy = self.share_data['subsidy']
 127         self.donation = self.share_data['donation']
 128
 129         if len(self.new_script) > 100:
 130             raise ValueError('new_script too long!')
 131
 132         self.previous_hash = self.previous_share_hash = self.share_data['previous_share_hash']
 133         self.nonce = self.share_data['nonce']
 134
 135         if len(self.nonce) > 100:
 136             raise ValueError('nonce too long!')
 137
 138         if len(self.share_data['coinbase']) > 100:
 139             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_data['coinbase']),))
 140
 141         self.pow_hash = net.BITCOIN_POW_FUNC(header)
 142         self.header_hash = bitcoin_data.block_header_type.hash256(header)
 143
 144         self.hash = new_share1a_type.hash256(self.as_share1a())
 145
 146         if self.pow_hash > self.target:
 147             print 'hash %x' % self.pow_hash
 148             print 'targ %x' % self.target
 149             raise ValueError('not enough work!')
 150
 151         if script.get_sigop_count(self.new_script) > 1:
 152             raise ValueError('too many sigops!')
 153
 154         self.stale_frac = self.share_data['stale_frac']/254 if self.share_data['stale_frac'] != 255 else None
 155
 156         # XXX eww
 157         self.time_seen = time.time()
 158         self.peer = None
 159
 160     def check(self, tracker, now, net):
 161         if self.header['timestamp'] <= TRANSITION_TIME - 3600:
 162             raise AssertionError('transitioning...')
 163
 164         share_info, gentx = new_generate_transaction(tracker, self.share_info['new_share_data'], self.header['target'], self.share_info['timestamp'], net)
 165         if share_info != self.share_info:
 166             raise ValueError('share difficulty invalid')
 167
 168         if bitcoin_data.check_merkle_branch(gentx, 0, self.merkle_branch) != self.header['merkle_root']:
 169             raise ValueError('''gentx doesn't match header via merkle_branch''')
 170
 171     def as_block(self, tracker, net):
 172         if self.other_txs is None:
 173             raise ValueError('share does not contain all txs')
 174
 175         share_info, gentx = new_generate_transaction(tracker, self.share_info['new_share_data'], self.header['target'], self.share_info['timestamp'], net)
 176         assert share_info == self.share_info
 177
 178         return dict(header=self.header, txs=[gentx] + self.other_txs)
 179
 180 def get_pool_attempts_per_second(tracker, previous_share_hash, net, dist=None):
 181     if dist is None:
 182         dist = net.TARGET_LOOKBEHIND
 183     near = tracker.shares[previous_share_hash]
 184     far = tracker.shares[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
 185     attempts = tracker.get_work(near.hash) - tracker.get_work(far.hash)
 186     time = near.timestamp - far.timestamp
 187     if time == 0:
 188         time = 1
 189     return attempts//time
 190
 191 def new_generate_transaction(tracker, new_share_data, block_target, desired_timestamp, net):
 192     previous_share_hash = new_share_data['previous_share_hash']
 193     new_script = new_share_data['new_script']
 194     subsidy = new_share_data['subsidy']
 195     donation = new_share_data['donation']
 196     assert 0 <= donation <= 65535
 197
 198     if len(new_share_data['coinbase']) > 100:
 199         raise ValueError('coinbase too long!')
 200
 201     previous_share = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
 202
 203     height, last = tracker.get_height_and_last(previous_share_hash)
 204     assert height >= net.CHAIN_LENGTH or last is None
 205     if height < net.TARGET_LOOKBEHIND:
 206         target = bitcoin_data.FloatingInteger.from_target_upper_bound(net.MAX_TARGET)
 207     else:
 208         attempts_per_second = get_pool_attempts_per_second(tracker, previous_share_hash, net)
 209         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1
 210         pre_target2 = math.clip(pre_target, (previous_share.target*9//10, previous_share.target*11//10))
 211         pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 212         target = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 213
 214     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
 215     max_att = net.SPREAD * attempts_to_block
 216
 217     this_att = min(bitcoin_data.target_to_average_attempts(target), max_att)
 218     other_weights, other_total_weight, other_donation_weight = tracker.get_cumulative_weights(previous_share_hash, min(height, net.CHAIN_LENGTH), 65535*max(0, max_att - this_att))
 219     assert other_total_weight == sum(other_weights.itervalues()) + other_donation_weight, (other_total_weight, sum(other_weights.itervalues()) + other_donation_weight)
 220     weights, total_weight, donation_weight = math.add_dicts([{new_script: this_att*(65535-donation)}, other_weights]), this_att*65535 + other_total_weight, this_att*donation + other_donation_weight
 221     assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 222
 223     SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 224
 225     # 1 satoshi is always donated so that a list of p2pool generated blocks can be easily found by looking at the donation address
 226     amounts = dict((script, (subsidy-1)*(199*weight)//(200*total_weight)) for (script, weight) in weights.iteritems())
 227     amounts[new_script] = amounts.get(new_script, 0) + (subsidy-1)//200
 228     amounts[SCRIPT] = amounts.get(SCRIPT, 0) + (subsidy-1)*(199*donation_weight)//(200*total_weight)
 229     amounts[SCRIPT] = amounts.get(SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra satoshis :P
 230
 231     if sum(amounts.itervalues()) != subsidy:
 232         raise ValueError()
 233     if any(x < 0 for x in amounts.itervalues()):
 234         raise ValueError()
 235
 236     dests = sorted(amounts.iterkeys(), key=lambda script: (amounts[script], script))
 237     dests = dests[-4000:] # block length limit, unlikely to ever be hit
 238
 239     share_info = dict(
 240         new_share_data=new_share_data,
 241         target=target,
 242         timestamp=math.clip(desired_timestamp, (previous_share.timestamp - 60, previous_share.timestamp + 60)) if previous_share is not None else desired_timestamp,
 243     )
 244
 245     return share_info, dict(
 246         version=1,
 247         tx_ins=[dict(
 248             previous_output=None,
 249             sequence=None,
 250             script=new_share_data['coinbase'].ljust(2, '\x00'),
 251         )],
 252         tx_outs=[dict(value=0, script='\x20' + bitcoin_data.HashType().pack(new_share_info_type.hash256(share_info)))] + [dict(value=amounts[script], script=script) for script in dests if amounts[script]],
 253         lock_time=0,
 254     )
 255
 256
 257 class OkayTracker(bitcoin_data.Tracker):
 258     def __init__(self, net):
 259         bitcoin_data.Tracker.__init__(self)
 260         self.net = net
 261         self.verified = bitcoin_data.Tracker()
 262         self.verified.get_nth_parent_hash = self.get_nth_parent_hash # self is a superset of self.verified
 263
 264         self.get_cumulative_weights = skiplists.WeightsSkipList(self)
 265
 266     def add(self, share, known_verified=False):
 267         bitcoin_data.Tracker.add(self, share)
 268         if known_verified:
 269             self.verified.add(share)
 270
 271     def attempt_verify(self, share, now):
 272         if share.hash in self.verified.shares:
 273             return True
 274         height, last = self.get_height_and_last(share.hash)
 275         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 276             raise AssertionError()
 277         try:
 278             share.check(self, now, self.net)
 279         except:
 280             log.err(None, 'Share check failed:')
 281             return False
 282         else:
 283             self.verified.add(share)
 284             return True
 285
 286     def think(self, ht, previous_block, now):
 287         desired = set()
 288
 289         # O(len(self.heads))
 290         #   make 'unverified heads' set?
 291         # for each overall head, attempt verification
 292         # if it fails, attempt on parent, and repeat
 293         # if no successful verification because of lack of parents, request parent
 294         bads = set()
 295         for head in set(self.heads) - set(self.verified.heads):
 296             head_height, last = self.get_height_and_last(head)
 297
 298             for share in itertools.islice(self.get_chain_known(head), None if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 299                 if self.attempt_verify(share, now):
 300                     break
 301                 if share.hash in self.heads:
 302                     bads.add(share.hash)
 303             else:
 304                 if last is not None:
 305                     desired.add((self.shares[random.choice(list(self.reverse_shares[last]))].peer, last))
 306         for bad in bads:
 307             assert bad not in self.verified.shares
 308             assert bad in self.heads
 309             if p2pool.DEBUG:
 310                 print "BAD", bad
 311             self.remove(bad)
 312
 313         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 314         for head in list(self.verified.heads):
 315             head_height, last_hash = self.verified.get_height_and_last(head)
 316             last_height, last_last_hash = self.get_height_and_last(last_hash)
 317             # XXX review boundary conditions
 318             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 319             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 320             get = min(want, can)
 321             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 322             for share in itertools.islice(self.get_chain_known(last_hash), get):
 323                 if not self.attempt_verify(share, now):
 324                     break
 325             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 326                 desired.add((self.verified.shares[random.choice(list(self.verified.reverse_shares[last_hash]))].peer, last_last_hash))
 327
 328         # decide best tree
 329         best_tail = max(self.verified.tails, key=lambda h: self.score(max(self.verified.tails[h], key=self.verified.get_height), ht)) if self.verified.tails else None
 330         # decide best verified head
 331         scores = sorted(self.verified.tails.get(best_tail, []), key=lambda h: (
 332             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 333             #self.verified.shares[h].peer is None,
 334             ht.get_min_height(self.verified.shares[h].previous_block),
 335             -self.verified.shares[h].time_seen
 336         ))
 337
 338
 339         if p2pool.DEBUG:
 340             print len(self.verified.tails), "chain tails and", len(self.verified.tails.get(best_tail, [])), 'chain heads. Top 10 heads:'
 341             if len(scores) > 10:
 342                 print '    ...'
 343             for h in scores[-10:]:
 344                 print '   ', format_hash(h), format_hash(self.verified.shares[h].previous_hash), (
 345                     self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 346                     self.verified.shares[h].peer is None,
 347                     ht.get_min_height(self.verified.shares[h].previous_block),
 348                     -self.verified.shares[h].time_seen
 349                 )
 350
 351         # eat away at heads
 352         if scores:
 353             for i in xrange(1000):
 354                 to_remove = set()
 355                 for share_hash, tail in self.heads.iteritems():
 356                     if share_hash in scores[-5:]:
 357                         #print 1
 358                         continue
 359                     if self.shares[share_hash].time_seen > time.time() - 300:
 360                         #print 2
 361                         continue
 362                     if share_hash not in self.verified.shares and max(self.shares[after_tail_hash].time_seen for after_tail_hash in self.reverse_shares.get(tail)) > time.time() - 120: # XXX stupid
 363                         #print 3
 364                         continue
 365                     to_remove.add(share_hash)
 366                 if not to_remove:
 367                     break
 368                 for share_hash in to_remove:
 369                     self.remove(share_hash)
 370                     if share_hash in self.verified.shares:
 371                         self.verified.remove(share_hash)
 372                 #print "_________", to_remove
 373
 374         # drop tails
 375         for i in xrange(1000):
 376             to_remove = set()
 377             for tail, heads in self.tails.iteritems():
 378                 if min(self.get_height(head) for head in heads) < 2*self.net.CHAIN_LENGTH + 10:
 379                     continue
 380                 for aftertail in self.reverse_shares.get(tail, set()):
 381                     if len(self.reverse_shares[self.shares[aftertail].previous_hash]) > 1: # XXX
 382                         print "raw"
 383                         continue
 384                     to_remove.add(aftertail)
 385             if not to_remove:
 386                 break
 387             # if removed from this, it must be removed from verified
 388             #start = time.time()
 389             for aftertail in to_remove:
 390                 if self.shares[aftertail].previous_hash not in self.tails:
 391                     print "erk", aftertail, self.shares[aftertail].previous_hash
 392                     continue
 393                 self.remove(aftertail)
 394                 if aftertail in self.verified.shares:
 395                     self.verified.remove(aftertail)
 396             #end = time.time()
 397             #print "removed! %i %f" % (len(to_remove), (end - start)/len(to_remove))
 398
 399         best = scores[-1] if scores else None
 400
 401         if best is not None:
 402             best_share = self.verified.shares[best]
 403             if ht.get_min_height(best_share.header['previous_block']) < ht.get_min_height(previous_block) and best_share.header_hash != previous_block and best_share.peer is not None:
 404                 if p2pool.DEBUG:
 405                     print 'Stale detected! %x < %x' % (best_share.header['previous_block'], previous_block)
 406                 best = best_share.previous_hash
 407
 408         return best, desired
 409
 410     @memoize.memoize_with_backing(expiring_dict.ExpiringDict(5, get_touches=False))
 411     def score(self, share_hash, ht):
 412         head_height, last = self.verified.get_height_and_last(share_hash)
 413         score2 = 0
 414         attempts = 0
 415         max_height = 0
 416         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
 417         for share in reversed(list(itertools.islice(self.verified.get_chain_known(share2_hash), self.net.CHAIN_LENGTH))):
 418             max_height = max(max_height, ht.get_min_height(share.header['previous_block']))
 419             attempts += bitcoin_data.target_to_average_attempts(share.target)
 420             this_score = attempts//(ht.get_highest_height() - max_height + 1)
 421             if this_score > score2:
 422                 score2 = this_score
 423         return min(head_height, self.net.CHAIN_LENGTH), score2
 424
 425 def format_hash(x):
 426     if x is None:
 427         return 'xxxxxxxx'
 428     return '%08x' % (x % 2**32)
 429
 430 class ShareStore(object):
 431     def __init__(self, prefix, net):
 432         self.filename = prefix
 433         self.dirname = os.path.dirname(os.path.abspath(prefix))
 434         self.filename = os.path.basename(os.path.abspath(prefix))
 435         self.net = net
 436         self.known = None # will be filename -> set of share hashes, set of verified hashes
 437
 438     def get_shares(self):
 439         if self.known is not None:
 440             raise AssertionError()
 441         known = {}
 442         filenames, next = self.get_filenames_and_next()
 443         for filename in filenames:
 444             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
 445             with open(filename, 'rb') as f:
 446                 for line in f:
 447                     try:
 448                         type_id_str, data_hex = line.strip().split(' ')
 449                         type_id = int(type_id_str)
 450                         if type_id == 0:
 451                             pass
 452                         elif type_id == 1:
 453                             pass
 454                         elif type_id == 2:
 455                             verified_hash = int(data_hex, 16)
 456                             yield 'verified_hash', verified_hash
 457                             verified_hashes.add(verified_hash)
 458                         elif type_id == 5:
 459                             share = NewShare.from_share(new_share_type.unpack(data_hex.decode('hex')), self.net)
 460                             yield 'share', share
 461                             share_hashes.add(share.hash)
 462                         else:
 463                             raise NotImplementedError("share type %i" % (type_id,))
 464                     except Exception:
 465                         log.err(None, "Error while reading saved shares, continuing where left off:")
 466         self.known = known
 467
 468     def _add_line(self, line):
 469         filenames, next = self.get_filenames_and_next()
 470         if filenames and os.path.getsize(filenames[-1]) < 10e6:
 471             filename = filenames[-1]
 472         else:
 473             filename = next
 474
 475         with open(filename, 'ab') as f:
 476             f.write(line + '\n')
 477
 478         return filename
 479
 480     def add_share(self, share):
 481         type_id, data = 5, new_share_type.pack(share.as_share())
 482         filename = self._add_line("%i %s" % (type_id, data.encode('hex')))
 483         share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 484         share_hashes.add(share.hash)
 485
 486     def add_verified_hash(self, share_hash):
 487         filename = self._add_line("%i %x" % (2, share_hash))
 488         share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 489         verified_hashes.add(share_hash)
 490
 491     def get_filenames_and_next(self):
 492         suffixes = sorted(int(x[len(self.filename):]) for x in os.listdir(self.dirname) if x.startswith(self.filename) and x[len(self.filename):].isdigit())
 493         return [os.path.join(self.dirname, self.filename + str(suffix)) for suffix in suffixes], os.path.join(self.dirname, self.filename + (str(suffixes[-1] + 1) if suffixes else str(0)))
 494
 495     def forget_share(self, share_hash):
 496         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 497             if share_hash in share_hashes:
 498                 share_hashes.remove(share_hash)
 499         self.check_remove()
 500
 501     def forget_verified_share(self, share_hash):
 502         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 503             if share_hash in verified_hashes:
 504                 verified_hashes.remove(share_hash)
 505         self.check_remove()
 506
 507     def check_remove(self):
 508         to_remove = set()
 509         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 510             #print filename, len(share_hashes) + len(verified_hashes)
 511             if not share_hashes and not verified_hashes:
 512                 to_remove.add(filename)
 513         for filename in to_remove:
 514             self.known.pop(filename)
 515             os.remove(filename)
 516             print "REMOVED", filename
 517
 518 class BitcoinMainnet(networks.BitcoinMainnet):
 519     SHARE_PERIOD = 10 # seconds
 520     CHAIN_LENGTH = 24*60*60//10//2 # shares
 521     TARGET_LOOKBEHIND = 200 # shares
 522     SPREAD = 3 # blocks
 523     IDENTIFIER = 'fc70035c7a81bc6f'.decode('hex')
 524     PREFIX = '2472ef181efcd37b'.decode('hex')
 525     NAME = 'bitcoin'
 526     P2P_PORT = 9333
 527     MAX_TARGET = 2**256//2**32 - 1
 528     PERSIST = True
 529     WORKER_PORT = 9332
 530
 531 class BitcoinTestnet(networks.BitcoinTestnet):
 532     SHARE_PERIOD = 1 # seconds
 533     CHAIN_LENGTH = 24*60*60//10//2 # shares
 534     TARGET_LOOKBEHIND = 200 # shares
 535     SPREAD = 3 # blocks
 536     IDENTIFIER = '5fc2be2d4f0d6bfb'.decode('hex')
 537     PREFIX = '3f6057a15036f441'.decode('hex')
 538     NAME = 'bitcoin_testnet'
 539     P2P_PORT = 19333
 540     MAX_TARGET = 2**256//2**32 - 1
 541     PERSIST = False
 542     WORKER_PORT = 19332
 543
 544 class NamecoinMainnet(networks.NamecoinMainnet):
 545     SHARE_PERIOD = 10 # seconds
 546     CHAIN_LENGTH = 24*60*60//10 # shares
 547     TARGET_LOOKBEHIND = 3600//10 # shares
 548     SPREAD = 3 # blocks
 549     IDENTIFIER = 'd5b1192062c4c454'.decode('hex')
 550     PREFIX = 'b56f3d0fb24fc982'.decode('hex')
 551     NAME = 'namecoin'
 552     P2P_PORT = 9334
 553     MAX_TARGET = 2**256//2**32 - 1
 554     PERSIST = True
 555     WORKER_PORT = 9331
 556
 557 class NamecoinTestnet(networks.NamecoinTestnet):
 558     SHARE_PERIOD = 1 # seconds
 559     CHAIN_LENGTH = 24*60*60//5 # shares
 560     TARGET_LOOKBEHIND = 200 # shares
 561     SPREAD = 3 # blocks
 562     IDENTIFIER = '8dd303d014a01a60'.decode('hex')
 563     PREFIX = '4d6581d24f51acbf'.decode('hex')
 564     NAME = 'namecoin_testnet'
 565     P2P_PORT = 19334
 566     MAX_TARGET = 2**256//2**20 - 1
 567     PERSIST = False
 568     WORKER_PORT = 19331
 569
 570 class IxcoinMainnet(networks.IxcoinMainnet):
 571     SHARE_PERIOD = 10 # seconds
 572     CHAIN_LENGTH = 24*60*60//10 # shares
 573     TARGET_LOOKBEHIND = 3600//10 # shares
 574     SPREAD = 3 # blocks
 575     IDENTIFIER = '27b564116e2a2666'.decode('hex')
 576     PREFIX = '9dd6c4a619401f2f'.decode('hex')
 577     NAME = 'ixcoin'
 578     P2P_PORT = 9335
 579     MAX_TARGET = 2**256//2**32 - 1
 580     PERSIST = True
 581     WORKER_PORT = 9330
 582
 583 class IxcoinTestnet(networks.IxcoinTestnet):
 584     SHARE_PERIOD = 1 # seconds
 585     CHAIN_LENGTH = 24*60*60//5 # shares
 586     TARGET_LOOKBEHIND = 200 # shares
 587     SPREAD = 3 # blocks
 588     IDENTIFIER = '7430cbeb01249e44'.decode('hex')
 589     PREFIX = '7cfffda946709c1f'.decode('hex')
 590     NAME = 'ixcoin_testnet'
 591     P2P_PORT = 19335
 592     MAX_TARGET = 2**256//2**20 - 1
 593     PERSIST = False
 594     WORKER_PORT = 19330
 595
 596 class I0coinMainnet(networks.I0coinMainnet):
 597     SHARE_PERIOD = 10 # seconds
 598     CHAIN_LENGTH = 24*60*60//10 # shares
 599     TARGET_LOOKBEHIND = 3600//10 # shares
 600     SPREAD = 3 # blocks
 601     IDENTIFIER = 'b32e3f10c2ff221b'.decode('hex')
 602     PREFIX = '6155537ed977a3b5'.decode('hex')
 603     NAME = 'i0coin'
 604     P2P_PORT = 9336
 605     MAX_TARGET = 2**256//2**32 - 1
 606     PERSIST = False
 607     WORKER_PORT = 9329
 608
 609 class I0coinTestnet(networks.I0coinTestnet):
 610     SHARE_PERIOD = 1 # seconds
 611     CHAIN_LENGTH = 24*60*60//5 # shares
 612     TARGET_LOOKBEHIND = 200 # shares
 613     SPREAD = 3 # blocks
 614     IDENTIFIER = '7712c1a8181b5f2e'.decode('hex')
 615     PREFIX = '792d2e7d770fbe68'.decode('hex')
 616     NAME = 'i0coin_testnet'
 617     P2P_PORT = 19336
 618     MAX_TARGET = 2**256//2**20 - 1
 619     PERSIST = False
 620     WORKER_PORT = 19329
 621
 622 class SolidcoinMainnet(networks.SolidcoinMainnet):
 623     SHARE_PERIOD = 10
 624     CHAIN_LENGTH = 24*60*60//10 # shares
 625     TARGET_LOOKBEHIND = 3600//10 # shares
 626     SPREAD = 3 # blocks
 627     IDENTIFIER = '9cc9c421cca258cd'.decode('hex')
 628     PREFIX = 'c059125b8070f00a'.decode('hex')
 629     NAME = 'solidcoin'
 630     P2P_PORT = 9337
 631     MAX_TARGET = 2**256//2**32 - 1
 632     PERSIST = True
 633     WORKER_PORT = 9328
 634
 635 class LitecoinMainnet(networks.LitecoinMainnet):
 636     SHARE_PERIOD = 10 # seconds
 637     CHAIN_LENGTH = 24*60*60//10//2 # shares
 638     TARGET_LOOKBEHIND = 200 # shares
 639     SPREAD = 12 # blocks
 640     IDENTIFIER = 'e037d5b8c6923410'.decode('hex')
 641     PREFIX = '7208c1a53ef629b0'.decode('hex')
 642     NAME = 'litecoin'
 643     P2P_PORT = 9338
 644     MAX_TARGET = 2**256//2**20 - 1
 645     PERSIST = True
 646     WORKER_PORT = 9327
 647
 648 class LitecoinTestnet(networks.LitecoinTestnet):
 649     SHARE_PERIOD = 1 # seconds
 650     CHAIN_LENGTH = 24*60*60//5 # shares
 651     TARGET_LOOKBEHIND = 200 # shares
 652     SPREAD = 12 # blocks
 653     IDENTIFIER = 'cca5e24ec6408b1e'.decode('hex')
 654     PREFIX = 'ad9614f6466a39cf'.decode('hex')
 655     NAME = 'litecoin_testnet'
 656     P2P_PORT = 19338
 657     MAX_TARGET = 2**256//2**17 - 1
 658     PERSIST = False
 659     WORKER_PORT = 19327
 660
 661 nets = dict((net.NAME, net) for net in set([BitcoinMainnet, BitcoinTestnet, NamecoinMainnet, NamecoinTestnet, IxcoinMainnet, IxcoinTestnet, I0coinMainnet, I0coinTestnet, SolidcoinMainnet, LitecoinMainnet, LitecoinTestnet]))