p2pool/data.py

   1 from __future__ import division
   2
   3 import hashlib
   4 import os
   5 import random
   6 import time
   7
   8 from twisted.python import log
   9
  10 import p2pool
  11 from p2pool import skiplists
  12 from p2pool.bitcoin import data as bitcoin_data, script, sha256
  13 from p2pool.util import math, forest, pack
  14
  15 # hashlink
  16
  17 hash_link_type = pack.ComposedType([
  18     ('state', pack.FixedStrType(32)),
  19     ('extra_data', pack.FixedStrType(0)), # bit of a hack, but since the donation script is at the end, const_ending is long enough to always make this empty
  20     ('length', pack.VarIntType()),
  21 ])
  22
  23 def prefix_to_hash_link(prefix, const_ending=''):
  24     assert prefix.endswith(const_ending), (prefix, const_ending)
  25     x = sha256.sha256(prefix)
  26     return dict(state=x.state, extra_data=x.buf[:max(0, len(x.buf)-len(const_ending))], length=x.length//8)
  27
  28 def check_hash_link(hash_link, data, const_ending=''):
  29     extra_length = hash_link['length'] % (512//8)
  30     assert len(hash_link['extra_data']) == max(0, extra_length - len(const_ending))
  31     extra = (hash_link['extra_data'] + const_ending)[len(hash_link['extra_data']) + len(const_ending) - extra_length:]
  32     assert len(extra) == extra_length
  33     return pack.IntType(256).unpack(hashlib.sha256(sha256.sha256(data, (hash_link['state'], extra, 8*hash_link['length'])).digest()).digest())
  34
  35 # shares
  36
  37 share_data_type = pack.ComposedType([
  38     ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  39     ('coinbase', pack.VarStrType()),
  40     ('nonce', pack.VarStrType()),
  41     ('new_script', pack.VarStrType()),
  42     ('subsidy', pack.IntType(64)),
  43     ('donation', pack.IntType(16)),
  44     ('stale_info', pack.IntType(8)), # 0 nothing, 253 orphan, 254 doa
  45 ])
  46
  47 share_info_type = pack.ComposedType([
  48     ('share_data', share_data_type),
  49     ('bits', bitcoin_data.FloatingIntegerType()),
  50     ('timestamp', pack.IntType(32)),
  51 ])
  52
  53 share1a_type = pack.ComposedType([
  54     ('header', bitcoin_data.block_header_type),
  55     ('share_info', share_info_type),
  56     ('merkle_branch', bitcoin_data.merkle_branch_type),
  57 ])
  58
  59 share1b_type = pack.ComposedType([
  60     ('header', bitcoin_data.block_header_type),
  61     ('share_info', share_info_type),
  62     ('other_txs', pack.ListType(bitcoin_data.tx_type)),
  63 ])
  64
  65 # new
  66
  67 small_block_header_type = pack.ComposedType([
  68     ('version', pack.VarIntType()), # XXX must be constrained to 32 bits
  69     ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
  70     ('timestamp', pack.IntType(32)),
  71     ('bits', bitcoin_data.FloatingIntegerType()),
  72     ('nonce', pack.IntType(32)),
  73 ])
  74
  75 new_share_data_type = pack.ComposedType([
  76     ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  77     ('coinbase', pack.VarStrType()),
  78     ('nonce', pack.IntType(32)),
  79     ('pubkey_hash', pack.IntType(160)),
  80     ('subsidy', pack.IntType(64)),
  81     ('donation', pack.IntType(16)),
  82     ('stale_info', pack.IntType(8)), # 0 nothing, 253 orphan, 254 doa
  83 ])
  84
  85 new_share_info_type = pack.ComposedType([
  86     ('share_data', new_share_data_type),
  87     ('max_bits', bitcoin_data.FloatingIntegerType()),
  88     ('bits', bitcoin_data.FloatingIntegerType()),
  89     ('timestamp', pack.IntType(32)),
  90 ])
  91
  92 new_share1a_type = pack.ComposedType([
  93     ('min_header', small_block_header_type),
  94     ('share_info', new_share_info_type),
  95     ('hash_link', hash_link_type),
  96     ('merkle_branch', bitcoin_data.merkle_branch_type),
  97 ])
  98
  99 new_share1b_type = pack.ComposedType([
 100     ('min_header', small_block_header_type),
 101     ('share_info', new_share_info_type),
 102     ('hash_link', hash_link_type),
 103     ('other_txs', pack.ListType(bitcoin_data.tx_type)),
 104 ])
 105
 106
 107 # type:
 108 # 0: share1a
 109 # 1: share1b
 110 # 2: new_share1a
 111 # 3: new_share1b
 112
 113 share_type = pack.ComposedType([
 114     ('type', pack.VarIntType()),
 115     ('contents', pack.VarStrType()),
 116 ])
 117
 118 class Share(object):
 119     __slots__ = 'header share_info merkle_branch other_txs timestamp share_data previous_hash target pow_hash header_hash hash time_seen peer net new_script max_target'.split(' ')
 120
 121     @classmethod
 122     def from_share(cls, share, net, peer):
 123         if share['type'] == 0:
 124             res = cls(net, peer, **share1a_type.unpack(share['contents']))
 125             if not (res.pow_hash > res.header['bits'].target):
 126                 raise ValueError('invalid share type')
 127             return res
 128         elif share['type'] == 1:
 129             share1b = share1b_type.unpack(share['contents'])
 130             res = cls(net, peer, merkle_branch=bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in share1b['other_txs']], 0), **share1b)
 131             if not (res.pow_hash <= res.header['bits'].target):
 132                 raise ValueError('invalid share type')
 133             return res
 134         elif share['type'] == 2:
 135             res = NewShare(net, peer, **new_share1a_type.unpack(share['contents']))
 136             if not (res.pow_hash > res.header['bits'].target):
 137                 raise ValueError('invalid share type')
 138             return res
 139         elif share['type'] == 3:
 140             share1b = new_share1b_type.unpack(share['contents'])
 141             res = NewShare(net, peer, merkle_branch=bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in share1b['other_txs']], 0), **share1b)
 142             if not (res.pow_hash <= res.header['bits'].target):
 143                 raise ValueError('invalid share type')
 144             return res
 145         else:
 146             raise ValueError('unknown share type: %r' % (share['type'],))
 147
 148     def __init__(self, net, peer, header, share_info, merkle_branch, other_txs=None):
 149         self.net = net
 150         self.peer = peer
 151
 152         if p2pool.DEBUG and other_txs is not None and bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in other_txs], 0) != merkle_branch:
 153             raise ValueError('merkle_branch and other_txs do not match')
 154
 155         if len(merkle_branch) > 16:
 156             raise ValueError('merkle_branch too long!')
 157
 158         self.header = header
 159         self.share_info = share_info
 160         self.merkle_branch = merkle_branch
 161
 162         self.share_data = self.share_info['share_data']
 163         self.target = self.max_target = self.share_info['bits'].target
 164         self.timestamp = self.share_info['timestamp']
 165         if self.timestamp > net.SWITCH_TIME + 60*60:
 166             raise ValueError('old share an hour after switch time')
 167
 168         if len(self.share_data['new_script']) > 100:
 169             raise ValueError('new_script too long!')
 170         if script.get_sigop_count(self.share_data['new_script']) > 1:
 171             raise ValueError('too many sigops!')
 172         self.new_script = self.share_data['new_script']
 173
 174         self.previous_hash = self.share_data['previous_share_hash']
 175
 176         if len(self.share_data['nonce']) > 100:
 177             raise ValueError('nonce too long!')
 178
 179         if len(self.share_data['coinbase']) > 100:
 180             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_data['coinbase']),))
 181
 182         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(header))
 183         self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(header))
 184
 185         self.hash = bitcoin_data.hash256(share1a_type.pack(self.as_share1a()))
 186
 187         if self.pow_hash > self.target:
 188             print 'hash %x' % self.pow_hash
 189             print 'targ %x' % self.target
 190             raise ValueError('not enough work!')
 191
 192         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 193             raise ValueError('other_txs provided when not a block solution')
 194         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 195             raise ValueError('other_txs not provided when a block solution')
 196
 197         self.other_txs = other_txs
 198
 199         # XXX eww
 200         self.time_seen = time.time()
 201
 202     def __repr__(self):
 203         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 204
 205     def check(self, tracker):
 206         share_info, gentx = generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.net)
 207         if share_info != self.share_info:
 208             raise ValueError('share difficulty invalid')
 209
 210         if bitcoin_data.check_merkle_branch(bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)), 0, self.merkle_branch) != self.header['merkle_root']:
 211             raise ValueError('''gentx doesn't match header via merkle_branch''')
 212
 213     def as_share(self):
 214         if self.pow_hash > self.header['bits'].target: # share1a
 215             return dict(type=0, contents=share1a_type.pack(self.as_share1a()))
 216         elif self.pow_hash <= self.header['bits'].target: # share1b
 217             if self.other_txs is None:
 218                 raise ValueError('share does not contain all txs')
 219             return dict(type=1, contents=share1b_type.pack(dict(header=self.header, share_info=self.share_info, other_txs=self.other_txs)))
 220         else:
 221             raise AssertionError()
 222
 223     def as_share1a(self):
 224         return dict(header=self.header, share_info=self.share_info, merkle_branch=self.merkle_branch)
 225
 226     def as_block(self, tracker):
 227         if self.other_txs is None:
 228             raise ValueError('share does not contain all txs')
 229
 230         share_info, gentx = generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.net)
 231         assert share_info == self.share_info
 232
 233         return dict(header=self.header, txs=[gentx] + self.other_txs)
 234
 235 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False):
 236     assert dist >= 2
 237     near = tracker.shares[previous_share_hash]
 238     far = tracker.shares[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
 239     attempts = tracker.get_work(near.hash) - tracker.get_work(far.hash) if not min_work else tracker.get_delta(near.hash).min_work - tracker.get_delta(far.hash).min_work
 240     time = near.timestamp - far.timestamp
 241     if time <= 0:
 242         time = 1
 243     return attempts//time
 244
 245 def get_average_stale_prop(tracker, share_hash, lookbehind):
 246     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] in [253, 254])
 247     return stales/(lookbehind + stales)
 248
 249 DONATION_SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
 250
 251 def generate_transaction(tracker, share_data, block_target, desired_timestamp, net):
 252     previous_share_hash = share_data['previous_share_hash']
 253     new_script = share_data['new_script']
 254     subsidy = share_data['subsidy']
 255     donation = share_data['donation']
 256     assert 0 <= donation <= 65535
 257
 258     if len(share_data['coinbase']) > 100:
 259         raise ValueError('coinbase too long!')
 260
 261     previous_share = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
 262
 263     chain_length = getattr(net, 'REAL_CHAIN_LENGTH_FUNC', lambda _: net.REAL_CHAIN_LENGTH)(previous_share.timestamp if previous_share is not None else None)
 264
 265     height, last = tracker.get_height_and_last(previous_share_hash)
 266     assert height >= chain_length or last is None
 267     if height < net.TARGET_LOOKBEHIND:
 268         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(net.MAX_TARGET)
 269     else:
 270         attempts_per_second = get_pool_attempts_per_second(tracker, previous_share_hash, net.TARGET_LOOKBEHIND)
 271         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1
 272         pre_target2 = math.clip(pre_target, (previous_share.target*9//10, previous_share.target*11//10))
 273         pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 274         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 275
 276     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
 277     max_att = net.SPREAD * attempts_to_block
 278
 279     this_att = min(bitcoin_data.target_to_average_attempts(bits.target), max_att)
 280     other_weights, other_total_weight, other_donation_weight = tracker.get_cumulative_weights(previous_share_hash, min(height, chain_length), 65535*max(0, max_att - this_att))
 281     assert other_total_weight == sum(other_weights.itervalues()) + other_donation_weight, (other_total_weight, sum(other_weights.itervalues()) + other_donation_weight)
 282     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
 283     assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 284
 285     # 1 satoshi is always donated so that a list of p2pool generated blocks can be easily found by looking at the donation address
 286     amounts = dict((script, (subsidy-1)*(199*weight)//(200*total_weight)) for (script, weight) in weights.iteritems())
 287     amounts[new_script] = amounts.get(new_script, 0) + (subsidy-1)//200
 288     amounts[DONATION_SCRIPT] = amounts.get(DONATION_SCRIPT, 0) + (subsidy-1)*(199*donation_weight)//(200*total_weight)
 289     amounts[DONATION_SCRIPT] = amounts.get(DONATION_SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra satoshis :P
 290
 291     if sum(amounts.itervalues()) != subsidy:
 292         raise ValueError()
 293     if any(x < 0 for x in amounts.itervalues()):
 294         raise ValueError()
 295
 296     dests = sorted(amounts.iterkeys(), key=lambda script: (amounts[script], script))
 297     dests = dests[-4000:] # block length limit, unlikely to ever be hit
 298
 299     share_info = dict(
 300         share_data=share_data,
 301         bits=bits,
 302         timestamp=math.clip(desired_timestamp, (previous_share.timestamp - 60, previous_share.timestamp + 60)) if previous_share is not None else desired_timestamp,
 303     )
 304
 305     return share_info, dict(
 306         version=1,
 307         tx_ins=[dict(
 308             previous_output=None,
 309             sequence=None,
 310             script=share_data['coinbase'].ljust(2, '\x00'),
 311         )],
 312         tx_outs=[dict(value=0, script='\x20' + pack.IntType(256).pack(bitcoin_data.hash256(share_info_type.pack(share_info))))] + [dict(value=amounts[script], script=script) for script in dests if amounts[script]],
 313         lock_time=0,
 314     )
 315
 316 ref_type = pack.ComposedType([
 317     ('identifier', pack.FixedStrType(64//8)),
 318     ('share_info', new_share_info_type),
 319 ])
 320
 321 gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 322
 323 def new_generate_transaction(tracker, share_data, block_target, desired_timestamp, desired_target, net):
 324     previous_share = tracker.shares[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 325
 326     height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 327     assert height >= net.REAL_CHAIN_LENGTH or last is None
 328     if height < net.TARGET_LOOKBEHIND:
 329         pre_target3 = net.MAX_TARGET
 330     else:
 331         attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True)
 332         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1
 333         pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 334         pre_target3 = math.clip(pre_target2, (0, net.MAX_TARGET))
 335     max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 336     bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 337
 338     weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 339         min(height, net.REAL_CHAIN_LENGTH),
 340         65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 341     )
 342     assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 343
 344     amounts = dict((script, share_data['subsidy']*(199*weight)//(200*total_weight)) for script, weight in weights.iteritems()) # 99.5% goes according to weights prior to this share
 345     this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 346     amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 347     amounts[DONATION_SCRIPT] = amounts.get(DONATION_SCRIPT, 0) + share_data['subsidy'] - sum(amounts.itervalues()) # all that's left over is the donation weight and some extra satoshis due to rounding
 348
 349     if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 350         raise ValueError()
 351
 352     dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 353
 354     share_info = dict(
 355         share_data=share_data,
 356         max_bits=max_bits,
 357         bits=bits,
 358         timestamp=math.clip(desired_timestamp, (
 359             (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 360             (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 361         )) if previous_share is not None else desired_timestamp,
 362     )
 363
 364     return share_info, dict(
 365         version=1,
 366         tx_ins=[dict(
 367             previous_output=None,
 368             sequence=None,
 369             script=share_data['coinbase'].ljust(2, '\x00'),
 370         )],
 371         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]] + [dict(
 372             value=0,
 373             script='\x20' + pack.IntType(256).pack(bitcoin_data.hash256(ref_type.pack(dict(
 374                 identifier=net.IDENTIFIER,
 375                 share_info=share_info,
 376             )))),
 377         )],
 378         lock_time=0,
 379     )
 380
 381 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
 382     weights, total_weight, donation_weight = tracker.get_cumulative_weights(best_share_hash, min(tracker.get_height(best_share_hash), net.REAL_CHAIN_LENGTH), 65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target))
 383     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
 384     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
 385     return res
 386
 387 class NewShare(object):
 388     __slots__ = 'net min_header share_info hash_link merkle_branch other_txs hash share_data max_target target timestamp previous_hash new_script gentx_hash header pow_hash header_hash time_seen peer'.split(' ')
 389
 390     def __init__(self, net, peer, min_header, share_info, hash_link, merkle_branch, other_txs=None):
 391         if len(share_info['share_data']['coinbase']) > 100:
 392             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_data['coinbase']),))
 393
 394         if len(merkle_branch) > 16:
 395             raise ValueError('merkle_branch too long!')
 396
 397         if p2pool.DEBUG and other_txs is not None and bitcoin_data.calculate_merkle_branch([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in other_txs], 0) != merkle_branch:
 398             raise ValueError('merkle_branch and other_txs do not match')
 399
 400         assert not hash_link['extra_data'], repr(hash_link['extra_data'])
 401
 402         self.net = net
 403         self.peer = peer
 404         self.min_header = min_header
 405         self.share_info = share_info
 406         self.hash_link = hash_link
 407         self.merkle_branch = merkle_branch
 408         self.other_txs = other_txs
 409
 410         self.hash = bitcoin_data.hash256(share_type.pack(self.as_share(block_hint=other_txs is not None)))
 411         self.share_data = self.share_info['share_data']
 412         self.max_target = self.share_info['max_bits'].target
 413         self.target = self.share_info['bits'].target
 414         self.timestamp = self.share_info['timestamp']
 415         self.previous_hash = self.share_data['previous_share_hash']
 416         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 417         if self.timestamp < net.SWITCH_TIME - 60*60:
 418             raise ValueError('new share an hour before switch time')
 419
 420         self.gentx_hash = check_hash_link(
 421             hash_link,
 422             pack.IntType(256).pack(bitcoin_data.hash256(ref_type.pack(dict(
 423                 identifier=net.IDENTIFIER,
 424                 share_info=share_info,
 425             )))) + pack.IntType(32).pack(0),
 426             gentx_before_refhash,
 427         )
 428         merkle_root = bitcoin_data.check_merkle_branch(self.gentx_hash, 0, merkle_branch)
 429         self.header = dict(min_header, merkle_root=merkle_root)
 430         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 431         self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 432
 433         if self.pow_hash > self.target:
 434             print 'hash %x' % self.pow_hash
 435             print 'targ %x' % self.target
 436             raise ValueError('not enough work!')
 437
 438         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 439             raise ValueError('other_txs provided when not a block solution')
 440         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 441             raise ValueError('other_txs not provided when a block solution')
 442
 443         # XXX eww
 444         self.time_seen = time.time()
 445
 446     def __repr__(self):
 447         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 448
 449     def check(self, tracker):
 450         share_info, gentx = new_generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.net)
 451         if share_info != self.share_info:
 452             raise ValueError('share difficulty invalid')
 453         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 454             raise ValueError('''gentx doesn't match hash_link''')
 455
 456     def as_share(self, block_hint=None):
 457         if block_hint is None:
 458             block_hint = self.pow_hash <= self.header['bits'].target
 459         if not block_hint: # share1a
 460             return dict(type=2, contents=new_share1a_type.pack(dict(min_header=self.min_header, share_info=self.share_info, hash_link=self.hash_link, merkle_branch=self.merkle_branch)))
 461         else: # share1b
 462             if self.other_txs is None:
 463                 raise ValueError('share does not contain all txs')
 464             return dict(type=3, contents=new_share1b_type.pack(dict(min_header=self.min_header, share_info=self.share_info, hash_link=self.hash_link, other_txs=self.other_txs)))
 465
 466     def as_block(self, tracker):
 467         if self.other_txs is None:
 468             raise ValueError('share does not contain all txs')
 469
 470         share_info, gentx = new_generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.net)
 471         assert share_info == self.share_info
 472
 473         return dict(header=self.header, txs=[gentx] + self.other_txs)
 474
 475 class OkayTracker(forest.Tracker):
 476     def __init__(self, net, my_share_hashes, my_doa_share_hashes):
 477         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 478             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 479             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 480         )))
 481         self.net = net
 482         self.verified = forest.Tracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 483             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 484             my_count=lambda share: 1 if share.hash in my_share_hashes else 0,
 485             my_doa_count=lambda share: 1 if share.hash in my_doa_share_hashes else 0,
 486             my_orphan_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 253 else 0,
 487             my_dead_announce_count=lambda share: 1 if share.hash in my_share_hashes and share.share_data['stale_info'] == 254 else 0,
 488         )))
 489         self.verified.get_nth_parent_hash = self.get_nth_parent_hash # self is a superset of self.verified
 490
 491         self.get_cumulative_weights = skiplists.WeightsSkipList(self)
 492
 493     def attempt_verify(self, share):
 494         if share.hash in self.verified.shares:
 495             return True
 496         height, last = self.get_height_and_last(share.hash)
 497         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 498             raise AssertionError()
 499         try:
 500             share.check(self)
 501         except:
 502             log.err(None, 'Share check failed:')
 503             return False
 504         else:
 505             self.verified.add(share)
 506             return True
 507
 508     def think(self, block_rel_height_func, previous_block, bits):
 509         desired = set()
 510
 511         # O(len(self.heads))
 512         #   make 'unverified heads' set?
 513         # for each overall head, attempt verification
 514         # if it fails, attempt on parent, and repeat
 515         # if no successful verification because of lack of parents, request parent
 516         bads = set()
 517         for head in set(self.heads) - set(self.verified.heads):
 518             head_height, last = self.get_height_and_last(head)
 519
 520             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 521                 if self.attempt_verify(share):
 522                     break
 523                 if share.hash in self.heads:
 524                     bads.add(share.hash)
 525             else:
 526                 if last is not None:
 527                     desired.add((
 528                         self.shares[random.choice(list(self.reverse_shares[last]))].peer,
 529                         last,
 530                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 531                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 532                     ))
 533         for bad in bads:
 534             assert bad not in self.verified.shares
 535             assert bad in self.heads
 536             if p2pool.DEBUG:
 537                 print "BAD", bad
 538             self.remove(bad)
 539
 540         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 541         for head in list(self.verified.heads):
 542             head_height, last_hash = self.verified.get_height_and_last(head)
 543             last_height, last_last_hash = self.get_height_and_last(last_hash)
 544             # XXX review boundary conditions
 545             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 546             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 547             get = min(want, can)
 548             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 549             for share in self.get_chain(last_hash, get):
 550                 if not self.attempt_verify(share):
 551                     break
 552             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 553                 desired.add((
 554                     self.verified.shares[random.choice(list(self.verified.reverse_shares[last_hash]))].peer,
 555                     last_last_hash,
 556                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 557                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
 558                 ))
 559
 560         # decide best tree
 561         decorated_tails = sorted((self.score(max(self.verified.tails[tail_hash], key=self.verified.get_height), block_rel_height_func), tail_hash) for tail_hash in self.verified.tails) # XXX using get_height here is quite possibly incorrect and vulnerable
 562         if p2pool.DEBUG:
 563             print len(decorated_tails), 'tails:'
 564             for score, tail_hash in decorated_tails:
 565                 print format_hash(tail_hash), score
 566         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
 567
 568         # decide best verified head
 569         decorated_heads = sorted(((
 570             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
 571             #self.verified.shares[h].peer is None,
 572             (self.verified.shares[h].header['previous_block'], self.verified.shares[h].header['bits']) == (previous_block, bits) or self.verified.shares[h].peer is None,
 573             -self.verified.shares[h].time_seen,
 574         ), h) for h in self.verified.tails.get(best_tail, []))
 575         if p2pool.DEBUG:
 576             print len(decorated_heads), 'heads. Top 10:'
 577             for score, head_hash in decorated_heads[-10:]:
 578                 print '   ', format_hash(head_hash), format_hash(self.verified.shares[head_hash].previous_hash), score
 579         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
 580
 581         # eat away at heads
 582         if decorated_heads:
 583             for i in xrange(1000):
 584                 to_remove = set()
 585                 for share_hash, tail in self.heads.iteritems():
 586                     if share_hash in [head_hash for score, head_hash in decorated_heads[-5:]]:
 587                         #print 1
 588                         continue
 589                     if self.shares[share_hash].time_seen > time.time() - 300:
 590                         #print 2
 591                         continue
 592                     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
 593                         #print 3
 594                         continue
 595                     to_remove.add(share_hash)
 596                 if not to_remove:
 597                     break
 598                 for share_hash in to_remove:
 599                     self.remove(share_hash)
 600                     if share_hash in self.verified.shares:
 601                         self.verified.remove(share_hash)
 602                 #print "_________", to_remove
 603
 604         # drop tails
 605         for i in xrange(1000):
 606             to_remove = set()
 607             for tail, heads in self.tails.iteritems():
 608                 if min(self.get_height(head) for head in heads) < 2*self.net.CHAIN_LENGTH + 10:
 609                     continue
 610                 for aftertail in self.reverse_shares.get(tail, set()):
 611                     if len(self.reverse_shares[self.shares[aftertail].previous_hash]) > 1: # XXX
 612                         print "raw"
 613                         continue
 614                     to_remove.add(aftertail)
 615             if not to_remove:
 616                 break
 617             # if removed from this, it must be removed from verified
 618             #start = time.time()
 619             for aftertail in to_remove:
 620                 if self.shares[aftertail].previous_hash not in self.tails:
 621                     print "erk", aftertail, self.shares[aftertail].previous_hash
 622                     continue
 623                 self.remove(aftertail)
 624                 if aftertail in self.verified.shares:
 625                     self.verified.remove(aftertail)
 626             #end = time.time()
 627             #print "removed! %i %f" % (len(to_remove), (end - start)/len(to_remove))
 628
 629         if best is not None:
 630             best_share = self.verified.shares[best]
 631             if (best_share.header['previous_block'], best_share.header['bits']) != (previous_block, bits) and best_share.header_hash != previous_block and best_share.peer is not None:
 632                 if p2pool.DEBUG:
 633                     print 'Stale detected! %x < %x' % (best_share.header['previous_block'], previous_block)
 634                 best = best_share.previous_hash
 635
 636             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
 637             target_cutoff = 2**256//(self.net.SHARE_PERIOD*best_tail_score[1] + 1) * 2 if best_tail_score[1] is not None else 2**256-1
 638         else:
 639             timestamp_cutoff = int(time.time()) - 24*60*60
 640             target_cutoff = 2**256-1
 641
 642         if p2pool.DEBUG:
 643             print 'Desire %i shares. Cutoff: %s old diff>%.2f' % (len(desired), math.format_dt(time.time() - timestamp_cutoff), bitcoin_data.target_to_difficulty(target_cutoff))
 644             for peer, hash, ts, targ in desired:
 645                 print '   ', '%s:%i' % peer.addr if peer is not None else None, format_hash(hash), math.format_dt(time.time() - ts), bitcoin_data.target_to_difficulty(targ), ts >= timestamp_cutoff, targ <= target_cutoff
 646
 647         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff and targ <= target_cutoff]
 648
 649     def score(self, share_hash, block_rel_height_func):
 650         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
 651
 652         head_height = self.verified.get_height(share_hash)
 653         if head_height < self.net.CHAIN_LENGTH:
 654             return head_height, None
 655
 656         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
 657
 658         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
 659             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
 660
 661         return self.net.CHAIN_LENGTH, (self.verified.get_work(share_hash) - self.verified.get_work(end_point))//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
 662
 663 def format_hash(x):
 664     if x is None:
 665         return 'xxxxxxxx'
 666     return '%08x' % (x % 2**32)
 667
 668 class ShareStore(object):
 669     def __init__(self, prefix, net):
 670         self.filename = prefix
 671         self.dirname = os.path.dirname(os.path.abspath(prefix))
 672         self.filename = os.path.basename(os.path.abspath(prefix))
 673         self.net = net
 674         self.known = None # will be filename -> set of share hashes, set of verified hashes
 675         self.known_desired = None
 676
 677     def get_shares(self):
 678         if self.known is not None:
 679             raise AssertionError()
 680         known = {}
 681         filenames, next = self.get_filenames_and_next()
 682         for filename in filenames:
 683             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
 684             with open(filename, 'rb') as f:
 685                 for line in f:
 686                     try:
 687                         type_id_str, data_hex = line.strip().split(' ')
 688                         type_id = int(type_id_str)
 689                         if type_id == 0:
 690                             pass
 691                         elif type_id == 1:
 692                             pass
 693                         elif type_id == 2:
 694                             verified_hash = int(data_hex, 16)
 695                             yield 'verified_hash', verified_hash
 696                             verified_hashes.add(verified_hash)
 697                         elif type_id == 5:
 698                             share = Share.from_share(share_type.unpack(data_hex.decode('hex')), self.net, None)
 699                             yield 'share', share
 700                             share_hashes.add(share.hash)
 701                         else:
 702                             raise NotImplementedError("share type %i" % (type_id,))
 703                     except Exception:
 704                         log.err(None, "Error while reading saved shares, continuing where left off:")
 705         self.known = known
 706         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
 707
 708     def _add_line(self, line):
 709         filenames, next = self.get_filenames_and_next()
 710         if filenames and os.path.getsize(filenames[-1]) < 10e6:
 711             filename = filenames[-1]
 712         else:
 713             filename = next
 714
 715         with open(filename, 'ab') as f:
 716             f.write(line + '\n')
 717
 718         return filename
 719
 720     def add_share(self, share):
 721         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 722             if share.hash in share_hashes:
 723                 break
 724         else:
 725             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
 726             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 727             share_hashes.add(share.hash)
 728         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 729         share_hashes.add(share.hash)
 730
 731     def add_verified_hash(self, share_hash):
 732         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
 733             if share_hash in verified_hashes:
 734                 break
 735         else:
 736             filename = self._add_line("%i %x" % (2, share_hash))
 737             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
 738             verified_hashes.add(share_hash)
 739         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
 740         verified_hashes.add(share_hash)
 741
 742     def get_filenames_and_next(self):
 743         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())
 744         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)))
 745
 746     def forget_share(self, share_hash):
 747         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 748             if share_hash in share_hashes:
 749                 share_hashes.remove(share_hash)
 750         self.check_remove()
 751
 752     def forget_verified_share(self, share_hash):
 753         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 754             if share_hash in verified_hashes:
 755                 verified_hashes.remove(share_hash)
 756         self.check_remove()
 757
 758     def check_remove(self):
 759         to_remove = set()
 760         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
 761             #print filename, len(share_hashes) + len(verified_hashes)
 762             if not share_hashes and not verified_hashes:
 763                 to_remove.add(filename)
 764         for filename in to_remove:
 765             self.known.pop(filename)
 766             self.known_desired.pop(filename)
 767             os.remove(filename)
 768             print "REMOVED", filename