p2pool/data.py

   1 from __future__ import division
   2
   3 import hashlib
   4 import os
   5 import random
   6 import sys
   7 import time
   8
   9 from twisted.python import log
  10
  11 import p2pool
  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_type = pack.ComposedType([
  38     ('type', pack.VarIntType()),
  39     ('contents', pack.VarStrType()),
  40 ])
  41
  42 def load_share(share, net, peer):
  43     if share['type'] in [0, 1, 2, 3]:
  44         from p2pool import p2p
  45         raise p2p.PeerMisbehavingError('sent an obsolete share')
  46     elif share['type'] == 4:
  47         return Share(net, peer, other_txs=None, **Share.share1a_type.unpack(share['contents']))
  48     elif share['type'] == 5:
  49         share1b = Share.share1b_type.unpack(share['contents'])
  50         return Share(net, peer, merkle_link=bitcoin_data.calculate_merkle_link([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in share1b['other_txs']], 0), **share1b)
  51     elif share['type'] == NewShare.VERSION:
  52         return NewShare(net, peer, NewShare.share_type.unpack(share['contents']))
  53     elif share['type'] == NewNewShare.VERSION:
  54         return NewNewShare(net, peer, NewNewShare.share_type.unpack(share['contents']))
  55     else:
  56         raise ValueError('unknown share type: %r' % (share['type'],))
  57
  58 DONATION_SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
  59
  60 class NewNewShare(object):
  61     VERSION = 9
  62     SUCCESSOR = None
  63
  64     other_txs = None
  65
  66     small_block_header_type = pack.ComposedType([
  67         ('version', pack.VarIntType()),
  68         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
  69         ('timestamp', pack.IntType(32)),
  70         ('bits', bitcoin_data.FloatingIntegerType()),
  71         ('nonce', pack.IntType(32)),
  72     ])
  73
  74     share_info_type = pack.ComposedType([
  75         ('share_data', 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.EnumType(pack.IntType(8), dict((k, {0: None, 253: 'orphan', 254: 'doa'}.get(k, 'unk%i' % (k,))) for k in xrange(256)))),
  83             ('desired_version', pack.VarIntType()),
  84         ])),
  85         ('new_transaction_hashes', pack.ListType(pack.IntType(256))),
  86         ('transaction_hash_refs', pack.ListType(pack.ComposedType([ # compressed by referencing previous shares' hashes
  87             ('share_count', pack.VarIntType()),
  88             ('tx_count', pack.VarIntType()),
  89         ]))),
  90         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
  91         ('max_bits', bitcoin_data.FloatingIntegerType()),
  92         ('bits', bitcoin_data.FloatingIntegerType()),
  93         ('timestamp', pack.IntType(32)),
  94     ])
  95
  96     share_type = pack.ComposedType([
  97         ('min_header', small_block_header_type),
  98         ('share_info', share_info_type),
  99         ('ref_merkle_link', pack.ComposedType([
 100             ('branch', pack.ListType(pack.IntType(256))),
 101             ('index', pack.IntType(0)),
 102         ])),
 103         ('last_txout_nonce', pack.IntType(32)),
 104         ('hash_link', hash_link_type),
 105         ('merkle_link', pack.ComposedType([
 106             ('branch', pack.ListType(pack.IntType(256))),
 107             ('index', pack.IntType(0)), # it will always be 0
 108         ])),
 109     ])
 110
 111     ref_type = pack.ComposedType([
 112         ('identifier', pack.FixedStrType(64//8)),
 113         ('share_info', share_info_type),
 114     ])
 115
 116     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x24' + pack.IntType(256).pack(0) + pack.IntType(32).pack(0))[:2]
 117
 118     @classmethod
 119     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None, last_txout_nonce=0):
 120         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 121
 122         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 123         assert height >= net.REAL_CHAIN_LENGTH or last is None
 124         if height < net.TARGET_LOOKBEHIND:
 125             pre_target3 = net.MAX_TARGET
 126         else:
 127             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 128             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 129             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 130             pre_target3 = math.clip(pre_target2, (net.MIN_TARGET, net.MAX_TARGET))
 131         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 132         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 133
 134         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 135             min(height, net.REAL_CHAIN_LENGTH),
 136             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 137         )
 138         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 139
 140         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
 141         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 142         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 143         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
 144
 145         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 146             raise ValueError()
 147
 148         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 149
 150         new_transaction_hashes = []
 151         new_transaction_size = 0
 152         transaction_hash_refs = []
 153         other_transaction_hashes = []
 154
 155         for tx_hash in desired_other_transaction_hashes:
 156             for i, share in enumerate(tracker.get_chain(share_data['previous_share_hash'], min(height, 100))):
 157                 if tx_hash in share.new_transaction_hashes:
 158                     this = dict(share_count=i+1, tx_count=share.new_transaction_hashes.index(tx_hash))
 159                     break
 160             else:
 161                 if known_txs is not None:
 162                     this_size = bitcoin_data.tx_type.packed_size(known_txs[tx_hash])
 163                     if new_transaction_size + this_size > 50000: # only allow 50 kB of new txns/share
 164                         break
 165                     new_transaction_size += this_size
 166                 new_transaction_hashes.append(tx_hash)
 167                 this = dict(share_count=0, tx_count=len(new_transaction_hashes)-1)
 168             transaction_hash_refs.append(this)
 169             other_transaction_hashes.append(tx_hash)
 170
 171         share_info = dict(
 172             share_data=share_data,
 173             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 174             max_bits=max_bits,
 175             bits=bits,
 176             timestamp=math.clip(desired_timestamp, (
 177                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 178                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 179             )) if previous_share is not None else desired_timestamp,
 180             new_transaction_hashes=new_transaction_hashes,
 181             transaction_hash_refs=transaction_hash_refs,
 182         )
 183
 184         gentx = dict(
 185             version=1,
 186             tx_ins=[dict(
 187                 previous_output=None,
 188                 sequence=None,
 189                 script=share_data['coinbase'],
 190             )],
 191             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 192                 value=0,
 193                 script='\x24' + cls.get_ref_hash(net, share_info, ref_merkle_link) + pack.IntType(32).pack(last_txout_nonce),
 194             )],
 195             lock_time=0,
 196         )
 197
 198         def get_share(header, transactions):
 199             min_header=dict(header);del min_header['merkle_root']
 200             return cls(net, None, dict(
 201                 min_header=min_header,
 202                 share_info=share_info,
 203                 ref_merkle_link=dict(branch=[], index=0),
 204                 last_txout_nonce=last_txout_nonce,
 205                 hash_link=prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4-4], cls.gentx_before_refhash),
 206                 merkle_link=bitcoin_data.calculate_merkle_link([None] + other_transaction_hashes, 0),
 207             ))
 208
 209         return share_info, gentx, other_transaction_hashes, get_share
 210
 211     @classmethod
 212     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 213         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 214             identifier=net.IDENTIFIER,
 215             share_info=share_info,
 216         ))), ref_merkle_link))
 217
 218     __slots__ = 'net peer contents min_header share_info hash_link merkle_link hash share_data max_target target timestamp previous_hash new_script desired_version gentx_hash header pow_hash header_hash new_transaction_hashes time_seen'.split(' ')
 219
 220     def __init__(self, net, peer, contents):
 221         self.net = net
 222         self.peer = peer
 223         self.contents = contents
 224
 225         self.min_header = contents['min_header']
 226         self.share_info = contents['share_info']
 227         self.hash_link = contents['hash_link']
 228         self.merkle_link = contents['merkle_link']
 229
 230         if not (2 <= len(self.share_info['share_data']['coinbase']) <= 100):
 231             raise ValueError('''bad coinbase size! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 232
 233         if len(self.merkle_link['branch']) > 16:
 234             raise ValueError('merkle branch too long!')
 235
 236         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 237
 238         self.share_data = self.share_info['share_data']
 239         self.max_target = self.share_info['max_bits'].target
 240         self.target = self.share_info['bits'].target
 241         self.timestamp = self.share_info['timestamp']
 242         self.previous_hash = self.share_data['previous_share_hash']
 243         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 244         self.desired_version = self.share_data['desired_version']
 245
 246         for x in self.share_info['transaction_hash_refs']:
 247             assert x['share_count'] < 110
 248         for i, x in enumerate(self.share_info['new_transaction_hashes']):
 249             assert dict(share_count=0, tx_count=i) in self.share_info['transaction_hash_refs']
 250
 251         self.gentx_hash = check_hash_link(
 252             self.hash_link,
 253             self.get_ref_hash(net, self.share_info, contents['ref_merkle_link']) + pack.IntType(32).pack(self.contents['last_txout_nonce']) + pack.IntType(32).pack(0),
 254             self.gentx_before_refhash,
 255         )
 256         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, self.merkle_link)
 257         self.header = dict(self.min_header, merkle_root=merkle_root)
 258         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 259         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 260
 261         if self.target > net.MAX_TARGET:
 262             from p2pool import p2p
 263             raise p2p.PeerMisbehavingError('share target invalid')
 264
 265         if self.pow_hash > self.target:
 266             from p2pool import p2p
 267             raise p2p.PeerMisbehavingError('share PoW invalid')
 268
 269         self.new_transaction_hashes = self.share_info['new_transaction_hashes']
 270
 271         # XXX eww
 272         self.time_seen = time.time()
 273
 274     def __repr__(self):
 275         return 'Share' + repr((self.net, self.peer, self.contents))
 276
 277     def as_share(self):
 278         return dict(type=self.VERSION, contents=self.share_type.pack(self.contents))
 279
 280     def check(self, tracker):
 281         from p2pool import p2p
 282         if self.share_data['previous_share_hash'] is not None:
 283             previous_share = tracker.items[self.share_data['previous_share_hash']]
 284             if type(self) is type(previous_share):
 285                 pass
 286             elif type(self) is type(previous_share).SUCCESSOR:
 287                 if tracker.get_height(previous_share.hash) < self.net.CHAIN_LENGTH:
 288                     from p2pool import p2p
 289                     raise p2p.PeerMisbehavingError('switch without enough history')
 290
 291                 # switch only valid if 85% of hashes in [self.net.CHAIN_LENGTH*9//10, self.net.CHAIN_LENGTH] for new version
 292                 counts = get_desired_version_counts(tracker,
 293                     tracker.get_nth_parent_hash(previous_share.hash, self.net.CHAIN_LENGTH*9//10), self.net.CHAIN_LENGTH//10)
 294                 if counts.get(self.VERSION, 0) < sum(counts.itervalues())*85//100:
 295                     raise p2p.PeerMisbehavingError('switch without enough hash power upgraded')
 296             else:
 297                 raise p2p.PeerMisbehavingError('''%s can't follow %s''' % (type(self).__name__, type(previous_share).__name__))
 298
 299         other_tx_hashes = [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 300
 301         share_info, gentx, other_tx_hashes2, get_share = self.generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.contents['ref_merkle_link'], other_tx_hashes, self.net, last_txout_nonce=self.contents['last_txout_nonce'])
 302         assert other_tx_hashes2 == other_tx_hashes
 303         if share_info != self.share_info:
 304             raise ValueError('share_info invalid')
 305         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 306             raise ValueError('''gentx doesn't match hash_link''')
 307
 308         if bitcoin_data.calculate_merkle_link([None] + other_tx_hashes, 0) != self.merkle_link:
 309             raise ValueError('merkle_link and other_tx_hashes do not match')
 310
 311         return gentx # only used by as_block
 312
 313     def get_other_tx_hashes(self, tracker):
 314         return [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 315
 316     def _get_other_txs(self, tracker, known_txs):
 317         other_tx_hashes = self.get_other_tx_hashes(tracker)
 318
 319         if not all(tx_hash in known_txs for tx_hash in other_tx_hashes):
 320             return None # not all txs present
 321
 322         return [known_txs[tx_hash] for tx_hash in other_tx_hashes]
 323
 324     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 325         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 326             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 327
 328         if self.pow_hash <= self.header['bits'].target:
 329             return -1, 'block solution'
 330
 331         other_txs = self._get_other_txs(tracker, known_txs)
 332         if other_txs is None:
 333             return True, 'not all txs present'
 334         else:
 335             all_txs_size = sum(bitcoin_data.tx_type.packed_size(tx) for tx in other_txs)
 336             if all_txs_size > 1000000:
 337                 return True, 'txs over block size limit'
 338
 339             new_txs_size = sum(bitcoin_data.tx_type.packed_size(known_txs[tx_hash]) for tx_hash in self.share_info['new_transaction_hashes'])
 340             if new_txs_size > 50000:
 341                 return True, 'new txs over limit'
 342
 343         return False, None
 344
 345     def as_block(self, tracker, known_txs):
 346         other_txs = self._get_other_txs(tracker, known_txs)
 347         if other_txs is None:
 348             return None # not all txs present
 349         return dict(header=self.header, txs=[self.check(tracker)] + other_txs)
 350
 351 class Share(object):
 352     VERSION = 7
 353     SUCCESSOR = NewNewShare
 354
 355     small_block_header_type = pack.ComposedType([
 356         ('version', pack.VarIntType()), # XXX must be constrained to 32 bits
 357         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 358         ('timestamp', pack.IntType(32)),
 359         ('bits', bitcoin_data.FloatingIntegerType()),
 360         ('nonce', pack.IntType(32)),
 361     ])
 362
 363     share_data_type = pack.ComposedType([
 364         ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 365         ('coinbase', pack.VarStrType()),
 366         ('nonce', pack.IntType(32)),
 367         ('pubkey_hash', pack.IntType(160)),
 368         ('subsidy', pack.IntType(64)),
 369         ('donation', pack.IntType(16)),
 370         ('stale_info', pack.EnumType(pack.IntType(8), dict((k, {0: None, 253: 'orphan', 254: 'doa'}.get(k, 'unk%i' % (k,))) for k in xrange(256)))),
 371         ('desired_version', pack.VarIntType()),
 372     ])
 373
 374     share_info_type = pack.ComposedType([
 375         ('share_data', share_data_type),
 376         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 377         ('max_bits', bitcoin_data.FloatingIntegerType()),
 378         ('bits', bitcoin_data.FloatingIntegerType()),
 379         ('timestamp', pack.IntType(32)),
 380     ])
 381
 382     share_common_type = pack.ComposedType([
 383         ('min_header', small_block_header_type),
 384         ('share_info', share_info_type),
 385         ('ref_merkle_link', pack.ComposedType([
 386             ('branch', pack.ListType(pack.IntType(256))),
 387             ('index', pack.VarIntType()),
 388         ])),
 389         ('hash_link', hash_link_type),
 390     ])
 391     share1a_type = pack.ComposedType([
 392         ('common', share_common_type),
 393         ('merkle_link', pack.ComposedType([
 394             ('branch', pack.ListType(pack.IntType(256))),
 395             ('index', pack.IntType(0)), # it will always be 0
 396         ])),
 397     ])
 398     share1b_type = pack.ComposedType([
 399         ('common', share_common_type),
 400         ('other_txs', pack.ListType(bitcoin_data.tx_type)),
 401     ])
 402
 403     ref_type = pack.ComposedType([
 404         ('identifier', pack.FixedStrType(64//8)),
 405         ('share_info', share_info_type),
 406     ])
 407
 408     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 409
 410     @classmethod
 411     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None):
 412         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 413
 414         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 415         assert height >= net.REAL_CHAIN_LENGTH or last is None
 416         if height < net.TARGET_LOOKBEHIND:
 417             pre_target3 = net.MAX_TARGET
 418         else:
 419             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 420             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 421             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 422             pre_target3 = math.clip(pre_target2, (net.MIN_TARGET, net.MAX_TARGET))
 423         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 424         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 425
 426         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 427             min(height, net.REAL_CHAIN_LENGTH),
 428             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 429         )
 430         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 431
 432         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
 433         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 434         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 435         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
 436
 437         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 438             raise ValueError()
 439
 440         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 441
 442         share_info = dict(
 443             share_data=share_data,
 444             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 445             max_bits=max_bits,
 446             bits=bits,
 447             timestamp=math.clip(desired_timestamp, (
 448                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 449                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 450             )) if previous_share is not None else desired_timestamp,
 451         )
 452
 453         gentx = dict(
 454             version=1,
 455             tx_ins=[dict(
 456                 previous_output=None,
 457                 sequence=None,
 458                 script=share_data['coinbase'].ljust(2, '\x00'),
 459             )],
 460             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 461                 value=0,
 462                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 463             )],
 464             lock_time=0,
 465         )
 466
 467         def get_share(header, transactions):
 468             assert transactions[0] == gentx and [bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)) for tx in transactions[1:]] == desired_other_transaction_hashes
 469             min_header = dict(header);del min_header['merkle_root']
 470             hash_link = prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash)
 471             merkle_link = bitcoin_data.calculate_merkle_link([None] + desired_other_transaction_hashes, 0)
 472             pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(header))
 473             return cls(net, None, dict(
 474                 min_header=min_header, share_info=share_info, hash_link=hash_link,
 475                 ref_merkle_link=dict(branch=[], index=0),
 476             ), merkle_link=merkle_link, other_txs=transactions[1:] if pow_hash <= header['bits'].target else None)
 477
 478         return share_info, gentx, desired_other_transaction_hashes, get_share
 479
 480     @classmethod
 481     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 482         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 483             identifier=net.IDENTIFIER,
 484             share_info=share_info,
 485         ))), ref_merkle_link))
 486
 487     __slots__ = 'net peer common min_header share_info hash_link merkle_link other_txs hash share_data max_target target timestamp previous_hash new_script desired_version gentx_hash header pow_hash header_hash new_transaction_hashes time_seen'.split(' ')
 488
 489     def __init__(self, net, peer, common, merkle_link, other_txs):
 490         self.net = net
 491         self.peer = peer
 492         self.common = common
 493         self.min_header = common['min_header']
 494         self.share_info = common['share_info']
 495         self.hash_link = common['hash_link']
 496         self.merkle_link = merkle_link
 497         self.other_txs = other_txs
 498
 499         if len(self.share_info['share_data']['coinbase']) > 100:
 500             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 501
 502         if len(merkle_link['branch']) > 16:
 503             raise ValueError('merkle branch too long!')
 504
 505         if p2pool.DEBUG and other_txs is not None and bitcoin_data.calculate_merkle_link([0] + [bitcoin_data.hash256(bitcoin_data.tx_type.pack(x)) for x in other_txs], 0) != merkle_link:
 506             raise ValueError('merkle_link and other_txs do not match')
 507
 508         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 509
 510         self.share_data = self.share_info['share_data']
 511         self.max_target = self.share_info['max_bits'].target
 512         self.target = self.share_info['bits'].target
 513         self.timestamp = self.share_info['timestamp']
 514         self.previous_hash = self.share_data['previous_share_hash']
 515         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 516         self.desired_version = self.share_data['desired_version']
 517
 518         self.gentx_hash = check_hash_link(
 519             self.hash_link,
 520             self.get_ref_hash(net, self.share_info, common['ref_merkle_link']) + pack.IntType(32).pack(0),
 521             self.gentx_before_refhash,
 522         )
 523         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, merkle_link)
 524         self.header = dict(self.min_header, merkle_root=merkle_root)
 525         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 526         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 527
 528         if self.pow_hash > self.target:
 529             from p2pool import p2p
 530             raise p2p.PeerMisbehavingError('share PoW invalid')
 531
 532         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 533             raise ValueError('other_txs provided when not a block solution')
 534         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 535             raise ValueError('other_txs not provided when a block solution')
 536
 537         self.new_transaction_hashes = []
 538
 539         # XXX eww
 540         self.time_seen = time.time()
 541
 542     def __repr__(self):
 543         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 544
 545     def as_share1a(self):
 546         return dict(type=4, contents=self.share1a_type.pack(dict(common=self.common, merkle_link=self.merkle_link)))
 547
 548     def as_share1b(self):
 549         return dict(type=5, contents=self.share1b_type.pack(dict(common=self.common, other_txs=self.other_txs)))
 550
 551     def as_share(self):
 552         if not self.pow_hash <= self.header['bits'].target: # share1a
 553             return self.as_share1a()
 554         else:
 555             return self.as_share1b()
 556
 557     def check(self, tracker):
 558         from p2pool import p2p
 559         if self.share_data['previous_share_hash'] is not None:
 560             previous_share = tracker.items[self.share_data['previous_share_hash']]
 561             if type(self) is type(previous_share):
 562                 pass
 563             elif type(self) is type(previous_share).SUCCESSOR:
 564                 if tracker.get_height(previous_share.hash) < self.net.CHAIN_LENGTH:
 565                     from p2pool import p2p
 566                     raise p2p.PeerMisbehavingError('switch without enough history')
 567
 568                 # switch only valid if 85% of hashes in [self.net.CHAIN_LENGTH*9//10, self.net.CHAIN_LENGTH] for new version
 569                 counts = get_desired_version_counts(tracker,
 570                     tracker.get_nth_parent_hash(previous_share.hash, self.net.CHAIN_LENGTH*9//10), self.net.CHAIN_LENGTH//10)
 571                 if counts.get(self.VERSION, 0) < sum(counts.itervalues())*85//100:
 572                     raise p2p.PeerMisbehavingError('switch without enough hash power upgraded')
 573             else:
 574                 raise p2p.PeerMisbehavingError('''%s can't follow %s''' % (type(self).__name__, type(previous_share).__name__))
 575
 576         share_info, gentx, other_transaction_hashes, get_share = self.generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.common['ref_merkle_link'], [], self.net) # ok because desired_other_transaction_hashes is only used in get_share
 577         if share_info != self.share_info:
 578             raise ValueError('share_info invalid')
 579         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 580             raise ValueError('''gentx doesn't match hash_link''')
 581         return gentx # only used by as_block
 582
 583     def get_other_tx_hashes(self, tracker):
 584         return []
 585
 586     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 587         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 588             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 589
 590         if self.pow_hash <= self.header['bits'].target:
 591             return -1, 'block solution'
 592
 593         return False, None
 594
 595     def as_block(self, tracker, known_txs):
 596         if self.other_txs is None:
 597             raise ValueError('share does not contain all txs')
 598         return dict(header=self.header, txs=[self.check(tracker)] + self.other_txs)
 599
 600 class NewShare(object):
 601     VERSION = 8
 602     SUCCESSOR = NewNewShare
 603
 604     other_txs = None
 605
 606     small_block_header_type = pack.ComposedType([
 607         ('version', pack.VarIntType()),
 608         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 609         ('timestamp', pack.IntType(32)),
 610         ('bits', bitcoin_data.FloatingIntegerType()),
 611         ('nonce', pack.IntType(32)),
 612     ])
 613
 614     share_info_type = pack.ComposedType([
 615         ('share_data', pack.ComposedType([
 616             ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 617             ('coinbase', pack.VarStrType()),
 618             ('nonce', pack.IntType(32)),
 619             ('pubkey_hash', pack.IntType(160)),
 620             ('subsidy', pack.IntType(64)),
 621             ('donation', pack.IntType(16)),
 622             ('stale_info', pack.EnumType(pack.IntType(8), dict((k, {0: None, 253: 'orphan', 254: 'doa'}.get(k, 'unk%i' % (k,))) for k in xrange(256)))),
 623             ('desired_version', pack.VarIntType()),
 624         ])),
 625         ('new_transaction_hashes', pack.ListType(pack.IntType(256))),
 626         ('transaction_hash_refs', pack.ListType(pack.ComposedType([ # compressed by referencing previous shares' hashes
 627             ('share_count', pack.VarIntType()),
 628             ('tx_count', pack.VarIntType()),
 629         ]))),
 630         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 631         ('max_bits', bitcoin_data.FloatingIntegerType()),
 632         ('bits', bitcoin_data.FloatingIntegerType()),
 633         ('timestamp', pack.IntType(32)),
 634     ])
 635
 636     share_type = pack.ComposedType([
 637         ('min_header', small_block_header_type),
 638         ('share_info', share_info_type),
 639         ('ref_merkle_link', pack.ComposedType([
 640             ('branch', pack.ListType(pack.IntType(256))),
 641             ('index', pack.IntType(0)),
 642         ])),
 643         ('hash_link', hash_link_type),
 644         ('merkle_link', pack.ComposedType([
 645             ('branch', pack.ListType(pack.IntType(256))),
 646             ('index', pack.IntType(0)), # it will always be 0
 647         ])),
 648     ])
 649
 650     ref_type = pack.ComposedType([
 651         ('identifier', pack.FixedStrType(64//8)),
 652         ('share_info', share_info_type),
 653     ])
 654
 655     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 656
 657     @classmethod
 658     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None):
 659         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 660
 661         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 662         assert height >= net.REAL_CHAIN_LENGTH or last is None
 663         if height < net.TARGET_LOOKBEHIND:
 664             pre_target3 = net.MAX_TARGET
 665         else:
 666             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 667             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 668             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 669             pre_target3 = math.clip(pre_target2, (net.MIN_TARGET, net.MAX_TARGET))
 670         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 671         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 672
 673         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 674             min(height, net.REAL_CHAIN_LENGTH),
 675             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 676         )
 677         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 678
 679         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
 680         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 681         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 682         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
 683
 684         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 685             raise ValueError()
 686
 687         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 688
 689         new_transaction_hashes = []
 690         new_transaction_size = 0
 691         transaction_hash_refs = []
 692         other_transaction_hashes = []
 693
 694         for tx_hash in desired_other_transaction_hashes:
 695             for i, share in enumerate(tracker.get_chain(share_data['previous_share_hash'], min(height, 100))):
 696                 if tx_hash in share.new_transaction_hashes:
 697                     this = dict(share_count=i+1, tx_count=share.new_transaction_hashes.index(tx_hash))
 698                     break
 699             else:
 700                 if known_txs is not None:
 701                     this_size = bitcoin_data.tx_type.packed_size(known_txs[tx_hash])
 702                     if new_transaction_size + this_size > 50000: # only allow 50 kB of new txns/share
 703                         break
 704                     new_transaction_size += this_size
 705                 new_transaction_hashes.append(tx_hash)
 706                 this = dict(share_count=0, tx_count=len(new_transaction_hashes)-1)
 707             transaction_hash_refs.append(this)
 708             other_transaction_hashes.append(tx_hash)
 709
 710         share_info = dict(
 711             share_data=share_data,
 712             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 713             max_bits=max_bits,
 714             bits=bits,
 715             timestamp=math.clip(desired_timestamp, (
 716                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 717                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 718             )) if previous_share is not None else desired_timestamp,
 719             new_transaction_hashes=new_transaction_hashes,
 720             transaction_hash_refs=transaction_hash_refs,
 721         )
 722
 723         gentx = dict(
 724             version=1,
 725             tx_ins=[dict(
 726                 previous_output=None,
 727                 sequence=None,
 728                 script=share_data['coinbase'],
 729             )],
 730             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 731                 value=0,
 732                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 733             )],
 734             lock_time=0,
 735         )
 736
 737         def get_share(header, transactions):
 738             min_header=dict(header);del min_header['merkle_root']
 739             return cls(net, None, dict(
 740                 min_header=min_header,
 741                 share_info=share_info,
 742                 ref_merkle_link=dict(branch=[], index=0),
 743                 hash_link=prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash),
 744                 merkle_link=bitcoin_data.calculate_merkle_link([None] + other_transaction_hashes, 0),
 745             ))
 746
 747         return share_info, gentx, other_transaction_hashes, get_share
 748
 749     @classmethod
 750     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 751         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 752             identifier=net.IDENTIFIER,
 753             share_info=share_info,
 754         ))), ref_merkle_link))
 755
 756     __slots__ = 'net peer contents min_header share_info hash_link merkle_link hash share_data max_target target timestamp previous_hash new_script desired_version gentx_hash header pow_hash header_hash new_transaction_hashes time_seen'.split(' ')
 757
 758     def __init__(self, net, peer, contents):
 759         self.net = net
 760         self.peer = peer
 761         self.contents = contents
 762
 763         self.min_header = contents['min_header']
 764         self.share_info = contents['share_info']
 765         self.hash_link = contents['hash_link']
 766         self.merkle_link = contents['merkle_link']
 767
 768         if not (2 <= len(self.share_info['share_data']['coinbase']) <= 100):
 769             raise ValueError('''bad coinbase size! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 770
 771         if len(self.merkle_link['branch']) > 16:
 772             raise ValueError('merkle branch too long!')
 773
 774         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 775
 776         self.share_data = self.share_info['share_data']
 777         self.max_target = self.share_info['max_bits'].target
 778         self.target = self.share_info['bits'].target
 779         self.timestamp = self.share_info['timestamp']
 780         self.previous_hash = self.share_data['previous_share_hash']
 781         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 782         self.desired_version = self.share_data['desired_version']
 783
 784         for x in self.share_info['transaction_hash_refs']:
 785             assert x['share_count'] < 110
 786         for i, x in enumerate(self.share_info['new_transaction_hashes']):
 787             assert dict(share_count=0, tx_count=i) in self.share_info['transaction_hash_refs']
 788
 789         self.gentx_hash = check_hash_link(
 790             self.hash_link,
 791             self.get_ref_hash(net, self.share_info, contents['ref_merkle_link']) + pack.IntType(32).pack(0),
 792             self.gentx_before_refhash,
 793         )
 794         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, self.merkle_link)
 795         self.header = dict(self.min_header, merkle_root=merkle_root)
 796         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 797         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 798
 799         if self.target > net.MAX_TARGET:
 800             from p2pool import p2p
 801             raise p2p.PeerMisbehavingError('share target invalid')
 802
 803         if self.pow_hash > self.target:
 804             from p2pool import p2p
 805             raise p2p.PeerMisbehavingError('share PoW invalid')
 806
 807         self.new_transaction_hashes = self.share_info['new_transaction_hashes']
 808
 809         # XXX eww
 810         self.time_seen = time.time()
 811
 812     def __repr__(self):
 813         return 'Share' + repr((self.net, self.peer, self.contents))
 814
 815     def as_share(self):
 816         return dict(type=self.VERSION, contents=self.share_type.pack(self.contents))
 817
 818     def check(self, tracker):
 819         from p2pool import p2p
 820         if self.share_data['previous_share_hash'] is not None:
 821             previous_share = tracker.items[self.share_data['previous_share_hash']]
 822             if type(self) is type(previous_share):
 823                 pass
 824             elif type(self) is type(previous_share).SUCCESSOR:
 825                 if tracker.get_height(previous_share.hash) < self.net.CHAIN_LENGTH:
 826                     from p2pool import p2p
 827                     raise p2p.PeerMisbehavingError('switch without enough history')
 828
 829                 # switch only valid if 85% of hashes in [self.net.CHAIN_LENGTH*9//10, self.net.CHAIN_LENGTH] for new version
 830                 counts = get_desired_version_counts(tracker,
 831                     tracker.get_nth_parent_hash(previous_share.hash, self.net.CHAIN_LENGTH*9//10), self.net.CHAIN_LENGTH//10)
 832                 if counts.get(self.VERSION, 0) < sum(counts.itervalues())*85//100:
 833                     raise p2p.PeerMisbehavingError('switch without enough hash power upgraded')
 834             else:
 835                 raise p2p.PeerMisbehavingError('''%s can't follow %s''' % (type(self).__name__, type(previous_share).__name__))
 836
 837         other_tx_hashes = [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 838
 839         share_info, gentx, other_tx_hashes2, get_share = self.generate_transaction(tracker, self.share_info['share_data'], self.header['bits'].target, self.share_info['timestamp'], self.share_info['bits'].target, self.contents['ref_merkle_link'], other_tx_hashes, self.net)
 840         assert other_tx_hashes2 == other_tx_hashes
 841         if share_info != self.share_info:
 842             raise ValueError('share_info invalid')
 843         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 844             raise ValueError('''gentx doesn't match hash_link''')
 845
 846         if bitcoin_data.calculate_merkle_link([None] + other_tx_hashes, 0) != self.merkle_link:
 847             raise ValueError('merkle_link and other_tx_hashes do not match')
 848
 849         return gentx # only used by as_block
 850
 851     def get_other_tx_hashes(self, tracker):
 852         return [tracker.items[tracker.get_nth_parent_hash(self.hash, x['share_count'])].share_info['new_transaction_hashes'][x['tx_count']] for x in self.share_info['transaction_hash_refs']]
 853
 854     def _get_other_txs(self, tracker, known_txs):
 855         other_tx_hashes = self.get_other_tx_hashes(tracker)
 856
 857         if not all(tx_hash in known_txs for tx_hash in other_tx_hashes):
 858             return None # not all txs present
 859
 860         return [known_txs[tx_hash] for tx_hash in other_tx_hashes]
 861
 862     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 863         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 864             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 865
 866         if self.pow_hash <= self.header['bits'].target:
 867             return -1, 'block solution'
 868
 869         other_txs = self._get_other_txs(tracker, known_txs)
 870         if other_txs is None:
 871             return True, 'not all txs present'
 872         else:
 873             all_txs_size = sum(bitcoin_data.tx_type.packed_size(tx) for tx in other_txs)
 874             if all_txs_size > 1000000:
 875                 return True, 'txs over block size limit'
 876
 877             new_txs_size = sum(bitcoin_data.tx_type.packed_size(known_txs[tx_hash]) for tx_hash in self.share_info['new_transaction_hashes'])
 878             if new_txs_size > 50000:
 879                 return True, 'new txs over limit'
 880
 881         return False, None
 882
 883     def as_block(self, tracker, known_txs):
 884         other_txs = self._get_other_txs(tracker, known_txs)
 885         if other_txs is None:
 886             return None # not all txs present
 887         return dict(header=self.header, txs=[self.check(tracker)] + other_txs)
 888
 889
 890 class WeightsSkipList(forest.TrackerSkipList):
 891     # share_count, weights, total_weight
 892
 893     def get_delta(self, element):
 894         from p2pool.bitcoin import data as bitcoin_data
 895         share = self.tracker.items[element]
 896         att = bitcoin_data.target_to_average_attempts(share.target)
 897         return 1, {share.new_script: att*(65535-share.share_data['donation'])}, att*65535, att*share.share_data['donation']
 898
 899     def combine_deltas(self, (share_count1, weights1, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2)):
 900         return share_count1 + share_count2, math.add_dicts(weights1, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 901
 902     def initial_solution(self, start, (max_shares, desired_weight)):
 903         assert desired_weight % 65535 == 0, divmod(desired_weight, 65535)
 904         return 0, None, 0, 0
 905
 906     def apply_delta(self, (share_count1, weights_list, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2), (max_shares, desired_weight)):
 907         if total_weight1 + total_weight2 > desired_weight and share_count2 == 1:
 908             assert (desired_weight - total_weight1) % 65535 == 0
 909             script, = weights2.iterkeys()
 910             new_weights = {script: (desired_weight - total_weight1)//65535*weights2[script]//(total_weight2//65535)}
 911             return share_count1 + share_count2, (weights_list, new_weights), desired_weight, total_donation_weight1 + (desired_weight - total_weight1)//65535*total_donation_weight2//(total_weight2//65535)
 912         return share_count1 + share_count2, (weights_list, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 913
 914     def judge(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 915         if share_count > max_shares or total_weight > desired_weight:
 916             return 1
 917         elif share_count == max_shares or total_weight == desired_weight:
 918             return 0
 919         else:
 920             return -1
 921
 922     def finalize(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 923         assert share_count <= max_shares and total_weight <= desired_weight
 924         assert share_count == max_shares or total_weight == desired_weight
 925         return math.add_dicts(*math.flatten_linked_list(weights_list)), total_weight, total_donation_weight
 926
 927 class OkayTracker(forest.Tracker):
 928     def __init__(self, net):
 929         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 930             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 931             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 932         )))
 933         self.net = net
 934         self.verified = forest.SubsetTracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 935             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 936         )), subset_of=self)
 937         self.get_cumulative_weights = WeightsSkipList(self)
 938
 939     def attempt_verify(self, share):
 940         if share.hash in self.verified.items:
 941             return True
 942         height, last = self.get_height_and_last(share.hash)
 943         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 944             raise AssertionError()
 945         try:
 946             share.check(self)
 947         except:
 948             log.err(None, 'Share check failed:')
 949             return False
 950         else:
 951             self.verified.add(share)
 952             return True
 953
 954     def think(self, block_rel_height_func, previous_block, bits, known_txs):
 955         desired = set()
 956
 957         # O(len(self.heads))
 958         #   make 'unverified heads' set?
 959         # for each overall head, attempt verification
 960         # if it fails, attempt on parent, and repeat
 961         # if no successful verification because of lack of parents, request parent
 962         bads = set()
 963         for head in set(self.heads) - set(self.verified.heads):
 964             head_height, last = self.get_height_and_last(head)
 965
 966             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 967                 if self.attempt_verify(share):
 968                     break
 969                 if share.hash in self.heads:
 970                     bads.add(share.hash)
 971             else:
 972                 if last is not None:
 973                     desired.add((
 974                         self.items[random.choice(list(self.reverse[last]))].peer,
 975                         last,
 976                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 977                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 978                     ))
 979         for bad in bads:
 980             assert bad not in self.verified.items
 981             assert bad in self.heads
 982             if p2pool.DEBUG:
 983                 print "BAD", bad
 984             self.remove(bad)
 985
 986         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 987         for head in list(self.verified.heads):
 988             head_height, last_hash = self.verified.get_height_and_last(head)
 989             last_height, last_last_hash = self.get_height_and_last(last_hash)
 990             # XXX review boundary conditions
 991             want = max(self.net.CHAIN_LENGTH - head_height, 0)
 992             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
 993             get = min(want, can)
 994             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
 995             for share in self.get_chain(last_hash, get):
 996                 if not self.attempt_verify(share):
 997                     break
 998             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
 999                 desired.add((
1000                     self.items[random.choice(list(self.verified.reverse[last_hash]))].peer,
1001                     last_last_hash,
1002                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
1003                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
1004                 ))
1005
1006         # decide best tree
1007         decorated_tails = sorted((self.score(max(self.verified.tails[tail_hash], key=self.verified.get_work), block_rel_height_func), tail_hash) for tail_hash in self.verified.tails)
1008         if p2pool.DEBUG:
1009             print len(decorated_tails), 'tails:'
1010             for score, tail_hash in decorated_tails:
1011                 print format_hash(tail_hash), score
1012         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
1013
1014         # decide best verified head
1015         decorated_heads = sorted(((
1016             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
1017             #self.items[h].peer is None,
1018             -self.items[h].should_punish_reason(previous_block, bits, self, known_txs)[0],
1019             -self.items[h].time_seen,
1020         ), h) for h in self.verified.tails.get(best_tail, []))
1021         if p2pool.DEBUG:
1022             print len(decorated_heads), 'heads. Top 10:'
1023             for score, head_hash in decorated_heads[-10:]:
1024                 print '   ', format_hash(head_hash), format_hash(self.items[head_hash].previous_hash), score
1025         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
1026
1027         if best is not None:
1028             best_share = self.items[best]
1029             punish, punish_reason = best_share.should_punish_reason(previous_block, bits, self, known_txs)
1030             if punish > 0:
1031                 print 'Punishing share for %r! Jumping from %s to %s!' % (punish_reason, format_hash(best), format_hash(best_share.previous_hash))
1032                 best = best_share.previous_hash
1033
1034             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
1035             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
1036         else:
1037             timestamp_cutoff = int(time.time()) - 24*60*60
1038             target_cutoff = 2**256-1
1039
1040         if p2pool.DEBUG:
1041             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))
1042             for peer, hash, ts, targ in desired:
1043                 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
1044
1045         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff], decorated_heads
1046
1047     def score(self, share_hash, block_rel_height_func):
1048         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
1049
1050         head_height = self.verified.get_height(share_hash)
1051         if head_height < self.net.CHAIN_LENGTH:
1052             return head_height, None
1053
1054         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
1055
1056         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
1057             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
1058
1059         return self.net.CHAIN_LENGTH, self.verified.get_delta(share_hash, end_point).work//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
1060
1061 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False, integer=False):
1062     assert dist >= 2
1063     near = tracker.items[previous_share_hash]
1064     far = tracker.items[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
1065     attempts = tracker.get_delta(near.hash, far.hash).work if not min_work else tracker.get_delta(near.hash, far.hash).min_work
1066     time = near.timestamp - far.timestamp
1067     if time <= 0:
1068         time = 1
1069     if integer:
1070         return attempts//time
1071     return attempts/time
1072
1073 def get_average_stale_prop(tracker, share_hash, lookbehind):
1074     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] is not None)
1075     return stales/(lookbehind + stales)
1076
1077 def get_stale_counts(tracker, share_hash, lookbehind, rates=False):
1078     res = {}
1079     for share in tracker.get_chain(share_hash, lookbehind - 1):
1080         res['good'] = res.get('good', 0) + bitcoin_data.target_to_average_attempts(share.target)
1081         s = share.share_data['stale_info']
1082         if s is not None:
1083             res[s] = res.get(s, 0) + bitcoin_data.target_to_average_attempts(share.target)
1084     if rates:
1085         dt = tracker.items[share_hash].timestamp - tracker.items[tracker.get_nth_parent_hash(share_hash, lookbehind - 1)].timestamp
1086         res = dict((k, v/dt) for k, v in res.iteritems())
1087     return res
1088
1089 def get_user_stale_props(tracker, share_hash, lookbehind):
1090     res = {}
1091     for share in tracker.get_chain(share_hash, lookbehind - 1):
1092         stale, total = res.get(share.share_data['pubkey_hash'], (0, 0))
1093         total += 1
1094         if share.share_data['stale_info'] is not None:
1095             stale += 1
1096             total += 1
1097         res[share.share_data['pubkey_hash']] = stale, total
1098     return dict((pubkey_hash, stale/total) for pubkey_hash, (stale, total) in res.iteritems())
1099
1100 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
1101     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))
1102     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
1103     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
1104     return res
1105
1106 def get_desired_version_counts(tracker, best_share_hash, dist):
1107     res = {}
1108     for share in tracker.get_chain(best_share_hash, dist):
1109         res[share.desired_version] = res.get(share.desired_version, 0) + bitcoin_data.target_to_average_attempts(share.target)
1110     return res
1111
1112 def get_warnings(tracker, best_share, net, bitcoind_warning, bitcoind_work_value):
1113     res = []
1114
1115     desired_version_counts = get_desired_version_counts(tracker, best_share,
1116         min(net.CHAIN_LENGTH, 60*60//net.SHARE_PERIOD, tracker.get_height(best_share)))
1117     majority_desired_version = max(desired_version_counts, key=lambda k: desired_version_counts[k])
1118     if majority_desired_version > NewNewShare.VERSION and desired_version_counts[majority_desired_version] > sum(desired_version_counts.itervalues())/2:
1119         res.append('A MAJORITY OF SHARES CONTAIN A VOTE FOR AN UNSUPPORTED SHARE IMPLEMENTATION! (v%i with %i%% support)\n'
1120             'An upgrade is likely necessary. Check http://p2pool.forre.st/ for more information.' % (
1121                 majority_desired_version, 100*desired_version_counts[majority_desired_version]/sum(desired_version_counts.itervalues())))
1122
1123     if bitcoind_warning is not None:
1124         res.append('(from bitcoind) %s' % (bitcoind_warning,))
1125
1126     if time.time() > bitcoind_work_value['last_update'] + 60:
1127         res.append('''LOST CONTACT WITH BITCOIND for %s! Check that it isn't frozen or dead!''' % (math.format_dt(time.time() - bitcoind_work_value['last_update']),))
1128
1129     return res
1130
1131 def format_hash(x):
1132     if x is None:
1133         return 'xxxxxxxx'
1134     return '%08x' % (x % 2**32)
1135
1136 class ShareStore(object):
1137     def __init__(self, prefix, net):
1138         self.filename = prefix
1139         self.dirname = os.path.dirname(os.path.abspath(prefix))
1140         self.filename = os.path.basename(os.path.abspath(prefix))
1141         self.net = net
1142         self.known = None # will be filename -> set of share hashes, set of verified hashes
1143         self.known_desired = None
1144
1145     def get_shares(self):
1146         if self.known is not None:
1147             raise AssertionError()
1148         known = {}
1149         filenames, next = self.get_filenames_and_next()
1150         for filename in filenames:
1151             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
1152             with open(filename, 'rb') as f:
1153                 for line in f:
1154                     try:
1155                         type_id_str, data_hex = line.strip().split(' ')
1156                         type_id = int(type_id_str)
1157                         if type_id == 0:
1158                             pass
1159                         elif type_id == 1:
1160                             pass
1161                         elif type_id == 2:
1162                             verified_hash = int(data_hex, 16)
1163                             yield 'verified_hash', verified_hash
1164                             verified_hashes.add(verified_hash)
1165                         elif type_id == 5:
1166                             raw_share = share_type.unpack(data_hex.decode('hex'))
1167                             if raw_share['type'] in [0, 1, 2, 3, 6, 7]:
1168                                 continue
1169                             share = load_share(raw_share, self.net, None)
1170                             yield 'share', share
1171                             share_hashes.add(share.hash)
1172                         else:
1173                             raise NotImplementedError("share type %i" % (type_id,))
1174                     except Exception:
1175                         log.err(None, "HARMLESS error while reading saved shares, continuing where left off:")
1176         self.known = known
1177         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
1178
1179     def _add_line(self, line):
1180         filenames, next = self.get_filenames_and_next()
1181         if filenames and os.path.getsize(filenames[-1]) < 10e6:
1182             filename = filenames[-1]
1183         else:
1184             filename = next
1185
1186         with open(filename, 'ab') as f:
1187             f.write(line + '\n')
1188
1189         return filename
1190
1191     def add_share(self, share):
1192         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
1193             if share.hash in share_hashes:
1194                 break
1195         else:
1196             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
1197             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
1198             share_hashes.add(share.hash)
1199         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
1200         share_hashes.add(share.hash)
1201
1202     def add_verified_hash(self, share_hash):
1203         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
1204             if share_hash in verified_hashes:
1205                 break
1206         else:
1207             filename = self._add_line("%i %x" % (2, share_hash))
1208             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
1209             verified_hashes.add(share_hash)
1210         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
1211         verified_hashes.add(share_hash)
1212
1213     def get_filenames_and_next(self):
1214         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())
1215         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)))
1216
1217     def forget_share(self, share_hash):
1218         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1219             if share_hash in share_hashes:
1220                 share_hashes.remove(share_hash)
1221         self.check_remove()
1222
1223     def forget_verified_share(self, share_hash):
1224         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1225             if share_hash in verified_hashes:
1226                 verified_hashes.remove(share_hash)
1227         self.check_remove()
1228
1229     def check_remove(self):
1230         to_remove = set()
1231         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1232             #print filename, len(share_hashes) + len(verified_hashes)
1233             if not share_hashes and not verified_hashes:
1234                 to_remove.add(filename)
1235         for filename in to_remove:
1236             self.known.pop(filename)
1237             self.known_desired.pop(filename)
1238             os.remove(filename)
1239             print "REMOVED", filename