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         parents = tracker.get_height(self.hash) - 1
 315         if not all(x['share_count'] <= parents for x in self.share_info['transaction_hash_refs']):
 316             return None
 317         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']]
 318
 319     def _get_other_txs(self, tracker, known_txs):
 320         other_tx_hashes = self.get_other_tx_hashes(tracker)
 321         if other_tx_hashes is None:
 322             return None # not all parents present
 323
 324         if not all(tx_hash in known_txs for tx_hash in other_tx_hashes):
 325             return None # not all txs present
 326
 327         return [known_txs[tx_hash] for tx_hash in other_tx_hashes]
 328
 329     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 330         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 331             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 332
 333         if self.pow_hash <= self.header['bits'].target:
 334             return -1, 'block solution'
 335
 336         other_txs = self._get_other_txs(tracker, known_txs)
 337         if other_txs is None:
 338             return True, 'not all txs present'
 339         else:
 340             all_txs_size = sum(bitcoin_data.tx_type.packed_size(tx) for tx in other_txs)
 341             if all_txs_size > 1000000:
 342                 return True, 'txs over block size limit'
 343
 344             new_txs_size = sum(bitcoin_data.tx_type.packed_size(known_txs[tx_hash]) for tx_hash in self.share_info['new_transaction_hashes'])
 345             if new_txs_size > 50000:
 346                 return True, 'new txs over limit'
 347
 348         return False, None
 349
 350     def as_block(self, tracker, known_txs):
 351         other_txs = self._get_other_txs(tracker, known_txs)
 352         if other_txs is None:
 353             return None # not all txs present
 354         return dict(header=self.header, txs=[self.check(tracker)] + other_txs)
 355
 356 class Share(object):
 357     VERSION = 7
 358     SUCCESSOR = NewNewShare
 359
 360     small_block_header_type = pack.ComposedType([
 361         ('version', pack.VarIntType()), # XXX must be constrained to 32 bits
 362         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 363         ('timestamp', pack.IntType(32)),
 364         ('bits', bitcoin_data.FloatingIntegerType()),
 365         ('nonce', pack.IntType(32)),
 366     ])
 367
 368     share_data_type = pack.ComposedType([
 369         ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 370         ('coinbase', pack.VarStrType()),
 371         ('nonce', pack.IntType(32)),
 372         ('pubkey_hash', pack.IntType(160)),
 373         ('subsidy', pack.IntType(64)),
 374         ('donation', pack.IntType(16)),
 375         ('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)))),
 376         ('desired_version', pack.VarIntType()),
 377     ])
 378
 379     share_info_type = pack.ComposedType([
 380         ('share_data', share_data_type),
 381         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 382         ('max_bits', bitcoin_data.FloatingIntegerType()),
 383         ('bits', bitcoin_data.FloatingIntegerType()),
 384         ('timestamp', pack.IntType(32)),
 385     ])
 386
 387     share_common_type = pack.ComposedType([
 388         ('min_header', small_block_header_type),
 389         ('share_info', share_info_type),
 390         ('ref_merkle_link', pack.ComposedType([
 391             ('branch', pack.ListType(pack.IntType(256))),
 392             ('index', pack.VarIntType()),
 393         ])),
 394         ('hash_link', hash_link_type),
 395     ])
 396     share1a_type = pack.ComposedType([
 397         ('common', share_common_type),
 398         ('merkle_link', pack.ComposedType([
 399             ('branch', pack.ListType(pack.IntType(256))),
 400             ('index', pack.IntType(0)), # it will always be 0
 401         ])),
 402     ])
 403     share1b_type = pack.ComposedType([
 404         ('common', share_common_type),
 405         ('other_txs', pack.ListType(bitcoin_data.tx_type)),
 406     ])
 407
 408     ref_type = pack.ComposedType([
 409         ('identifier', pack.FixedStrType(64//8)),
 410         ('share_info', share_info_type),
 411     ])
 412
 413     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 414
 415     @classmethod
 416     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None):
 417         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 418
 419         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 420         assert height >= net.REAL_CHAIN_LENGTH or last is None
 421         if height < net.TARGET_LOOKBEHIND:
 422             pre_target3 = net.MAX_TARGET
 423         else:
 424             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 425             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 426             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 427             pre_target3 = math.clip(pre_target2, (net.MIN_TARGET, net.MAX_TARGET))
 428         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 429         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 430
 431         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 432             min(height, net.REAL_CHAIN_LENGTH),
 433             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 434         )
 435         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 436
 437         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
 438         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 439         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 440         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
 441
 442         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 443             raise ValueError()
 444
 445         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 446
 447         share_info = dict(
 448             share_data=share_data,
 449             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 450             max_bits=max_bits,
 451             bits=bits,
 452             timestamp=math.clip(desired_timestamp, (
 453                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 454                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 455             )) if previous_share is not None else desired_timestamp,
 456         )
 457
 458         gentx = dict(
 459             version=1,
 460             tx_ins=[dict(
 461                 previous_output=None,
 462                 sequence=None,
 463                 script=share_data['coinbase'].ljust(2, '\x00'),
 464             )],
 465             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 466                 value=0,
 467                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 468             )],
 469             lock_time=0,
 470         )
 471
 472         def get_share(header, transactions):
 473             assert transactions[0] == gentx and [bitcoin_data.hash256(bitcoin_data.tx_type.pack(tx)) for tx in transactions[1:]] == desired_other_transaction_hashes
 474             min_header = dict(header);del min_header['merkle_root']
 475             hash_link = prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash)
 476             merkle_link = bitcoin_data.calculate_merkle_link([None] + desired_other_transaction_hashes, 0)
 477             pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(header))
 478             return cls(net, None, dict(
 479                 min_header=min_header, share_info=share_info, hash_link=hash_link,
 480                 ref_merkle_link=dict(branch=[], index=0),
 481             ), merkle_link=merkle_link, other_txs=transactions[1:] if pow_hash <= header['bits'].target else None)
 482
 483         return share_info, gentx, desired_other_transaction_hashes, get_share
 484
 485     @classmethod
 486     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 487         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 488             identifier=net.IDENTIFIER,
 489             share_info=share_info,
 490         ))), ref_merkle_link))
 491
 492     __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(' ')
 493
 494     def __init__(self, net, peer, common, merkle_link, other_txs):
 495         self.net = net
 496         self.peer = peer
 497         self.common = common
 498         self.min_header = common['min_header']
 499         self.share_info = common['share_info']
 500         self.hash_link = common['hash_link']
 501         self.merkle_link = merkle_link
 502         self.other_txs = other_txs
 503
 504         if len(self.share_info['share_data']['coinbase']) > 100:
 505             raise ValueError('''coinbase too large! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 506
 507         if len(merkle_link['branch']) > 16:
 508             raise ValueError('merkle branch too long!')
 509
 510         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:
 511             raise ValueError('merkle_link and other_txs do not match')
 512
 513         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 514
 515         self.share_data = self.share_info['share_data']
 516         self.max_target = self.share_info['max_bits'].target
 517         self.target = self.share_info['bits'].target
 518         self.timestamp = self.share_info['timestamp']
 519         self.previous_hash = self.share_data['previous_share_hash']
 520         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 521         self.desired_version = self.share_data['desired_version']
 522
 523         self.gentx_hash = check_hash_link(
 524             self.hash_link,
 525             self.get_ref_hash(net, self.share_info, common['ref_merkle_link']) + pack.IntType(32).pack(0),
 526             self.gentx_before_refhash,
 527         )
 528         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, merkle_link)
 529         self.header = dict(self.min_header, merkle_root=merkle_root)
 530         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 531         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 532
 533         if self.pow_hash > self.target:
 534             from p2pool import p2p
 535             raise p2p.PeerMisbehavingError('share PoW invalid')
 536
 537         if other_txs is not None and not self.pow_hash <= self.header['bits'].target:
 538             raise ValueError('other_txs provided when not a block solution')
 539         if other_txs is None and self.pow_hash <= self.header['bits'].target:
 540             raise ValueError('other_txs not provided when a block solution')
 541
 542         self.new_transaction_hashes = []
 543
 544         # XXX eww
 545         self.time_seen = time.time()
 546
 547     def __repr__(self):
 548         return '<Share %s>' % (' '.join('%s=%r' % (k, getattr(self, k)) for k in self.__slots__),)
 549
 550     def as_share1a(self):
 551         return dict(type=4, contents=self.share1a_type.pack(dict(common=self.common, merkle_link=self.merkle_link)))
 552
 553     def as_share1b(self):
 554         return dict(type=5, contents=self.share1b_type.pack(dict(common=self.common, other_txs=self.other_txs)))
 555
 556     def as_share(self):
 557         if not self.pow_hash <= self.header['bits'].target: # share1a
 558             return self.as_share1a()
 559         else:
 560             return self.as_share1b()
 561
 562     def check(self, tracker):
 563         from p2pool import p2p
 564         if self.share_data['previous_share_hash'] is not None:
 565             previous_share = tracker.items[self.share_data['previous_share_hash']]
 566             if type(self) is type(previous_share):
 567                 pass
 568             elif type(self) is type(previous_share).SUCCESSOR:
 569                 if tracker.get_height(previous_share.hash) < self.net.CHAIN_LENGTH:
 570                     from p2pool import p2p
 571                     raise p2p.PeerMisbehavingError('switch without enough history')
 572
 573                 # switch only valid if 85% of hashes in [self.net.CHAIN_LENGTH*9//10, self.net.CHAIN_LENGTH] for new version
 574                 counts = get_desired_version_counts(tracker,
 575                     tracker.get_nth_parent_hash(previous_share.hash, self.net.CHAIN_LENGTH*9//10), self.net.CHAIN_LENGTH//10)
 576                 if counts.get(self.VERSION, 0) < sum(counts.itervalues())*85//100:
 577                     raise p2p.PeerMisbehavingError('switch without enough hash power upgraded')
 578             else:
 579                 raise p2p.PeerMisbehavingError('''%s can't follow %s''' % (type(self).__name__, type(previous_share).__name__))
 580
 581         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
 582         if share_info != self.share_info:
 583             raise ValueError('share_info invalid')
 584         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 585             raise ValueError('''gentx doesn't match hash_link''')
 586         return gentx # only used by as_block
 587
 588     def get_other_tx_hashes(self, tracker):
 589         return []
 590
 591     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 592         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 593             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 594
 595         if self.pow_hash <= self.header['bits'].target:
 596             return -1, 'block solution'
 597
 598         return False, None
 599
 600     def as_block(self, tracker, known_txs):
 601         if self.other_txs is None:
 602             raise ValueError('share does not contain all txs')
 603         return dict(header=self.header, txs=[self.check(tracker)] + self.other_txs)
 604
 605 class NewShare(object):
 606     VERSION = 8
 607     SUCCESSOR = NewNewShare
 608
 609     other_txs = None
 610
 611     small_block_header_type = pack.ComposedType([
 612         ('version', pack.VarIntType()),
 613         ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
 614         ('timestamp', pack.IntType(32)),
 615         ('bits', bitcoin_data.FloatingIntegerType()),
 616         ('nonce', pack.IntType(32)),
 617     ])
 618
 619     share_info_type = pack.ComposedType([
 620         ('share_data', pack.ComposedType([
 621             ('previous_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 622             ('coinbase', pack.VarStrType()),
 623             ('nonce', pack.IntType(32)),
 624             ('pubkey_hash', pack.IntType(160)),
 625             ('subsidy', pack.IntType(64)),
 626             ('donation', pack.IntType(16)),
 627             ('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)))),
 628             ('desired_version', pack.VarIntType()),
 629         ])),
 630         ('new_transaction_hashes', pack.ListType(pack.IntType(256))),
 631         ('transaction_hash_refs', pack.ListType(pack.ComposedType([ # compressed by referencing previous shares' hashes
 632             ('share_count', pack.VarIntType()),
 633             ('tx_count', pack.VarIntType()),
 634         ]))),
 635         ('far_share_hash', pack.PossiblyNoneType(0, pack.IntType(256))),
 636         ('max_bits', bitcoin_data.FloatingIntegerType()),
 637         ('bits', bitcoin_data.FloatingIntegerType()),
 638         ('timestamp', pack.IntType(32)),
 639     ])
 640
 641     share_type = pack.ComposedType([
 642         ('min_header', small_block_header_type),
 643         ('share_info', share_info_type),
 644         ('ref_merkle_link', pack.ComposedType([
 645             ('branch', pack.ListType(pack.IntType(256))),
 646             ('index', pack.IntType(0)),
 647         ])),
 648         ('hash_link', hash_link_type),
 649         ('merkle_link', pack.ComposedType([
 650             ('branch', pack.ListType(pack.IntType(256))),
 651             ('index', pack.IntType(0)), # it will always be 0
 652         ])),
 653     ])
 654
 655     ref_type = pack.ComposedType([
 656         ('identifier', pack.FixedStrType(64//8)),
 657         ('share_info', share_info_type),
 658     ])
 659
 660     gentx_before_refhash = pack.VarStrType().pack(DONATION_SCRIPT) + pack.IntType(64).pack(0) + pack.VarStrType().pack('\x20' + pack.IntType(256).pack(0))[:2]
 661
 662     @classmethod
 663     def generate_transaction(cls, tracker, share_data, block_target, desired_timestamp, desired_target, ref_merkle_link, desired_other_transaction_hashes, net, known_txs=None):
 664         previous_share = tracker.items[share_data['previous_share_hash']] if share_data['previous_share_hash'] is not None else None
 665
 666         height, last = tracker.get_height_and_last(share_data['previous_share_hash'])
 667         assert height >= net.REAL_CHAIN_LENGTH or last is None
 668         if height < net.TARGET_LOOKBEHIND:
 669             pre_target3 = net.MAX_TARGET
 670         else:
 671             attempts_per_second = get_pool_attempts_per_second(tracker, share_data['previous_share_hash'], net.TARGET_LOOKBEHIND, min_work=True, integer=True)
 672             pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1 if attempts_per_second else 2**256-1
 673             pre_target2 = math.clip(pre_target, (previous_share.max_target*9//10, previous_share.max_target*11//10))
 674             pre_target3 = math.clip(pre_target2, (net.MIN_TARGET, net.MAX_TARGET))
 675         max_bits = bitcoin_data.FloatingInteger.from_target_upper_bound(pre_target3)
 676         bits = bitcoin_data.FloatingInteger.from_target_upper_bound(math.clip(desired_target, (pre_target3//10, pre_target3)))
 677
 678         weights, total_weight, donation_weight = tracker.get_cumulative_weights(share_data['previous_share_hash'],
 679             min(height, net.REAL_CHAIN_LENGTH),
 680             65535*net.SPREAD*bitcoin_data.target_to_average_attempts(block_target),
 681         )
 682         assert total_weight == sum(weights.itervalues()) + donation_weight, (total_weight, sum(weights.itervalues()) + donation_weight)
 683
 684         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
 685         this_script = bitcoin_data.pubkey_hash_to_script2(share_data['pubkey_hash'])
 686         amounts[this_script] = amounts.get(this_script, 0) + share_data['subsidy']//200 # 0.5% goes to block finder
 687         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
 688
 689         if sum(amounts.itervalues()) != share_data['subsidy'] or any(x < 0 for x in amounts.itervalues()):
 690             raise ValueError()
 691
 692         dests = sorted(amounts.iterkeys(), key=lambda script: (script == DONATION_SCRIPT, amounts[script], script))[-4000:] # block length limit, unlikely to ever be hit
 693
 694         new_transaction_hashes = []
 695         new_transaction_size = 0
 696         transaction_hash_refs = []
 697         other_transaction_hashes = []
 698
 699         for tx_hash in desired_other_transaction_hashes:
 700             for i, share in enumerate(tracker.get_chain(share_data['previous_share_hash'], min(height, 100))):
 701                 if tx_hash in share.new_transaction_hashes:
 702                     this = dict(share_count=i+1, tx_count=share.new_transaction_hashes.index(tx_hash))
 703                     break
 704             else:
 705                 if known_txs is not None:
 706                     this_size = bitcoin_data.tx_type.packed_size(known_txs[tx_hash])
 707                     if new_transaction_size + this_size > 50000: # only allow 50 kB of new txns/share
 708                         break
 709                     new_transaction_size += this_size
 710                 new_transaction_hashes.append(tx_hash)
 711                 this = dict(share_count=0, tx_count=len(new_transaction_hashes)-1)
 712             transaction_hash_refs.append(this)
 713             other_transaction_hashes.append(tx_hash)
 714
 715         share_info = dict(
 716             share_data=share_data,
 717             far_share_hash=None if last is None and height < 99 else tracker.get_nth_parent_hash(share_data['previous_share_hash'], 99),
 718             max_bits=max_bits,
 719             bits=bits,
 720             timestamp=math.clip(desired_timestamp, (
 721                 (previous_share.timestamp + net.SHARE_PERIOD) - (net.SHARE_PERIOD - 1), # = previous_share.timestamp + 1
 722                 (previous_share.timestamp + net.SHARE_PERIOD) + (net.SHARE_PERIOD - 1),
 723             )) if previous_share is not None else desired_timestamp,
 724             new_transaction_hashes=new_transaction_hashes,
 725             transaction_hash_refs=transaction_hash_refs,
 726         )
 727
 728         gentx = dict(
 729             version=1,
 730             tx_ins=[dict(
 731                 previous_output=None,
 732                 sequence=None,
 733                 script=share_data['coinbase'],
 734             )],
 735             tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script] or script == DONATION_SCRIPT] + [dict(
 736                 value=0,
 737                 script='\x20' + cls.get_ref_hash(net, share_info, ref_merkle_link),
 738             )],
 739             lock_time=0,
 740         )
 741
 742         def get_share(header, transactions):
 743             min_header=dict(header);del min_header['merkle_root']
 744             return cls(net, None, dict(
 745                 min_header=min_header,
 746                 share_info=share_info,
 747                 ref_merkle_link=dict(branch=[], index=0),
 748                 hash_link=prefix_to_hash_link(bitcoin_data.tx_type.pack(gentx)[:-32-4], cls.gentx_before_refhash),
 749                 merkle_link=bitcoin_data.calculate_merkle_link([None] + other_transaction_hashes, 0),
 750             ))
 751
 752         return share_info, gentx, other_transaction_hashes, get_share
 753
 754     @classmethod
 755     def get_ref_hash(cls, net, share_info, ref_merkle_link):
 756         return pack.IntType(256).pack(bitcoin_data.check_merkle_link(bitcoin_data.hash256(cls.ref_type.pack(dict(
 757             identifier=net.IDENTIFIER,
 758             share_info=share_info,
 759         ))), ref_merkle_link))
 760
 761     __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(' ')
 762
 763     def __init__(self, net, peer, contents):
 764         self.net = net
 765         self.peer = peer
 766         self.contents = contents
 767
 768         self.min_header = contents['min_header']
 769         self.share_info = contents['share_info']
 770         self.hash_link = contents['hash_link']
 771         self.merkle_link = contents['merkle_link']
 772
 773         if not (2 <= len(self.share_info['share_data']['coinbase']) <= 100):
 774             raise ValueError('''bad coinbase size! %i bytes''' % (len(self.share_info['share_data']['coinbase']),))
 775
 776         if len(self.merkle_link['branch']) > 16:
 777             raise ValueError('merkle branch too long!')
 778
 779         assert not self.hash_link['extra_data'], repr(self.hash_link['extra_data'])
 780
 781         self.share_data = self.share_info['share_data']
 782         self.max_target = self.share_info['max_bits'].target
 783         self.target = self.share_info['bits'].target
 784         self.timestamp = self.share_info['timestamp']
 785         self.previous_hash = self.share_data['previous_share_hash']
 786         self.new_script = bitcoin_data.pubkey_hash_to_script2(self.share_data['pubkey_hash'])
 787         self.desired_version = self.share_data['desired_version']
 788
 789         for x in self.share_info['transaction_hash_refs']:
 790             assert x['share_count'] < 110
 791         for i, x in enumerate(self.share_info['new_transaction_hashes']):
 792             assert dict(share_count=0, tx_count=i) in self.share_info['transaction_hash_refs']
 793
 794         self.gentx_hash = check_hash_link(
 795             self.hash_link,
 796             self.get_ref_hash(net, self.share_info, contents['ref_merkle_link']) + pack.IntType(32).pack(0),
 797             self.gentx_before_refhash,
 798         )
 799         merkle_root = bitcoin_data.check_merkle_link(self.gentx_hash, self.merkle_link)
 800         self.header = dict(self.min_header, merkle_root=merkle_root)
 801         self.pow_hash = net.PARENT.POW_FUNC(bitcoin_data.block_header_type.pack(self.header))
 802         self.hash = self.header_hash = bitcoin_data.hash256(bitcoin_data.block_header_type.pack(self.header))
 803
 804         if self.target > net.MAX_TARGET:
 805             from p2pool import p2p
 806             raise p2p.PeerMisbehavingError('share target invalid')
 807
 808         if self.pow_hash > self.target:
 809             from p2pool import p2p
 810             raise p2p.PeerMisbehavingError('share PoW invalid')
 811
 812         self.new_transaction_hashes = self.share_info['new_transaction_hashes']
 813
 814         # XXX eww
 815         self.time_seen = time.time()
 816
 817     def __repr__(self):
 818         return 'Share' + repr((self.net, self.peer, self.contents))
 819
 820     def as_share(self):
 821         return dict(type=self.VERSION, contents=self.share_type.pack(self.contents))
 822
 823     def check(self, tracker):
 824         from p2pool import p2p
 825         if self.share_data['previous_share_hash'] is not None:
 826             previous_share = tracker.items[self.share_data['previous_share_hash']]
 827             if type(self) is type(previous_share):
 828                 pass
 829             elif type(self) is type(previous_share).SUCCESSOR:
 830                 if tracker.get_height(previous_share.hash) < self.net.CHAIN_LENGTH:
 831                     from p2pool import p2p
 832                     raise p2p.PeerMisbehavingError('switch without enough history')
 833
 834                 # switch only valid if 85% of hashes in [self.net.CHAIN_LENGTH*9//10, self.net.CHAIN_LENGTH] for new version
 835                 counts = get_desired_version_counts(tracker,
 836                     tracker.get_nth_parent_hash(previous_share.hash, self.net.CHAIN_LENGTH*9//10), self.net.CHAIN_LENGTH//10)
 837                 if counts.get(self.VERSION, 0) < sum(counts.itervalues())*85//100:
 838                     raise p2p.PeerMisbehavingError('switch without enough hash power upgraded')
 839             else:
 840                 raise p2p.PeerMisbehavingError('''%s can't follow %s''' % (type(self).__name__, type(previous_share).__name__))
 841
 842         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']]
 843
 844         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)
 845         assert other_tx_hashes2 == other_tx_hashes
 846         if share_info != self.share_info:
 847             raise ValueError('share_info invalid')
 848         if bitcoin_data.hash256(bitcoin_data.tx_type.pack(gentx)) != self.gentx_hash:
 849             raise ValueError('''gentx doesn't match hash_link''')
 850
 851         if bitcoin_data.calculate_merkle_link([None] + other_tx_hashes, 0) != self.merkle_link:
 852             raise ValueError('merkle_link and other_tx_hashes do not match')
 853
 854         return gentx # only used by as_block
 855
 856     def get_other_tx_hashes(self, tracker):
 857         parents = tracker.get_height(self.hash) - 1
 858         if not all(x['share_count'] <= parents for x in self.share_info['transaction_hash_refs']):
 859             return None
 860         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']]
 861
 862     def _get_other_txs(self, tracker, known_txs):
 863         other_tx_hashes = self.get_other_tx_hashes(tracker)
 864         if other_tx_hashes is None:
 865             return None # not all parents present
 866
 867         if not all(tx_hash in known_txs for tx_hash in other_tx_hashes):
 868             return None # not all txs present
 869
 870         return [known_txs[tx_hash] for tx_hash in other_tx_hashes]
 871
 872     def should_punish_reason(self, previous_block, bits, tracker, known_txs):
 873         if (self.header['previous_block'], self.header['bits']) != (previous_block, bits) and self.header_hash != previous_block and self.peer is not None:
 874             return True, 'Block-stale detected! %x < %x' % (self.header['previous_block'], previous_block)
 875
 876         if self.pow_hash <= self.header['bits'].target:
 877             return -1, 'block solution'
 878
 879         other_txs = self._get_other_txs(tracker, known_txs)
 880         if other_txs is None:
 881             return True, 'not all txs present'
 882         else:
 883             all_txs_size = sum(bitcoin_data.tx_type.packed_size(tx) for tx in other_txs)
 884             if all_txs_size > 1000000:
 885                 return True, 'txs over block size limit'
 886
 887             new_txs_size = sum(bitcoin_data.tx_type.packed_size(known_txs[tx_hash]) for tx_hash in self.share_info['new_transaction_hashes'])
 888             if new_txs_size > 50000:
 889                 return True, 'new txs over limit'
 890
 891         return False, None
 892
 893     def as_block(self, tracker, known_txs):
 894         other_txs = self._get_other_txs(tracker, known_txs)
 895         if other_txs is None:
 896             return None # not all txs present
 897         return dict(header=self.header, txs=[self.check(tracker)] + other_txs)
 898
 899
 900 class WeightsSkipList(forest.TrackerSkipList):
 901     # share_count, weights, total_weight
 902
 903     def get_delta(self, element):
 904         from p2pool.bitcoin import data as bitcoin_data
 905         share = self.tracker.items[element]
 906         att = bitcoin_data.target_to_average_attempts(share.target)
 907         return 1, {share.new_script: att*(65535-share.share_data['donation'])}, att*65535, att*share.share_data['donation']
 908
 909     def combine_deltas(self, (share_count1, weights1, total_weight1, total_donation_weight1), (share_count2, weights2, total_weight2, total_donation_weight2)):
 910         return share_count1 + share_count2, math.add_dicts(weights1, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 911
 912     def initial_solution(self, start, (max_shares, desired_weight)):
 913         assert desired_weight % 65535 == 0, divmod(desired_weight, 65535)
 914         return 0, None, 0, 0
 915
 916     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)):
 917         if total_weight1 + total_weight2 > desired_weight and share_count2 == 1:
 918             assert (desired_weight - total_weight1) % 65535 == 0
 919             script, = weights2.iterkeys()
 920             new_weights = {script: (desired_weight - total_weight1)//65535*weights2[script]//(total_weight2//65535)}
 921             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)
 922         return share_count1 + share_count2, (weights_list, weights2), total_weight1 + total_weight2, total_donation_weight1 + total_donation_weight2
 923
 924     def judge(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 925         if share_count > max_shares or total_weight > desired_weight:
 926             return 1
 927         elif share_count == max_shares or total_weight == desired_weight:
 928             return 0
 929         else:
 930             return -1
 931
 932     def finalize(self, (share_count, weights_list, total_weight, total_donation_weight), (max_shares, desired_weight)):
 933         assert share_count <= max_shares and total_weight <= desired_weight
 934         assert share_count == max_shares or total_weight == desired_weight
 935         return math.add_dicts(*math.flatten_linked_list(weights_list)), total_weight, total_donation_weight
 936
 937 class OkayTracker(forest.Tracker):
 938     def __init__(self, net):
 939         forest.Tracker.__init__(self, delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 940             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 941             min_work=lambda share: bitcoin_data.target_to_average_attempts(share.max_target),
 942         )))
 943         self.net = net
 944         self.verified = forest.SubsetTracker(delta_type=forest.get_attributedelta_type(dict(forest.AttributeDelta.attrs,
 945             work=lambda share: bitcoin_data.target_to_average_attempts(share.target),
 946         )), subset_of=self)
 947         self.get_cumulative_weights = WeightsSkipList(self)
 948
 949     def attempt_verify(self, share):
 950         if share.hash in self.verified.items:
 951             return True
 952         height, last = self.get_height_and_last(share.hash)
 953         if height < self.net.CHAIN_LENGTH + 1 and last is not None:
 954             raise AssertionError()
 955         try:
 956             share.check(self)
 957         except:
 958             log.err(None, 'Share check failed:')
 959             return False
 960         else:
 961             self.verified.add(share)
 962             return True
 963
 964     def think(self, block_rel_height_func, previous_block, bits, known_txs):
 965         desired = set()
 966
 967         # O(len(self.heads))
 968         #   make 'unverified heads' set?
 969         # for each overall head, attempt verification
 970         # if it fails, attempt on parent, and repeat
 971         # if no successful verification because of lack of parents, request parent
 972         bads = set()
 973         for head in set(self.heads) - set(self.verified.heads):
 974             head_height, last = self.get_height_and_last(head)
 975
 976             for share in self.get_chain(head, head_height if last is None else min(5, max(0, head_height - self.net.CHAIN_LENGTH))):
 977                 if self.attempt_verify(share):
 978                     break
 979                 if share.hash in self.heads:
 980                     bads.add(share.hash)
 981             else:
 982                 if last is not None:
 983                     desired.add((
 984                         self.items[random.choice(list(self.reverse[last]))].peer,
 985                         last,
 986                         max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
 987                         min(x.target for x in self.get_chain(head, min(head_height, 5))),
 988                     ))
 989         for bad in bads:
 990             assert bad not in self.verified.items
 991             assert bad in self.heads
 992             if p2pool.DEBUG:
 993                 print "BAD", bad
 994             self.remove(bad)
 995
 996         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
 997         for head in list(self.verified.heads):
 998             head_height, last_hash = self.verified.get_height_and_last(head)
 999             last_height, last_last_hash = self.get_height_and_last(last_hash)
1000             # XXX review boundary conditions
1001             want = max(self.net.CHAIN_LENGTH - head_height, 0)
1002             can = max(last_height - 1 - self.net.CHAIN_LENGTH, 0) if last_last_hash is not None else last_height
1003             get = min(want, can)
1004             #print 'Z', head_height, last_hash is None, last_height, last_last_hash is None, want, can, get
1005             for share in self.get_chain(last_hash, get):
1006                 if not self.attempt_verify(share):
1007                     break
1008             if head_height < self.net.CHAIN_LENGTH and last_last_hash is not None:
1009                 desired.add((
1010                     self.items[random.choice(list(self.verified.reverse[last_hash]))].peer,
1011                     last_last_hash,
1012                     max(x.timestamp for x in self.get_chain(head, min(head_height, 5))),
1013                     min(x.target for x in self.get_chain(head, min(head_height, 5))),
1014                 ))
1015
1016         # decide best tree
1017         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)
1018         if p2pool.DEBUG:
1019             print len(decorated_tails), 'tails:'
1020             for score, tail_hash in decorated_tails:
1021                 print format_hash(tail_hash), score
1022         best_tail_score, best_tail = decorated_tails[-1] if decorated_tails else (None, None)
1023
1024         # decide best verified head
1025         decorated_heads = sorted(((
1026             self.verified.get_work(self.verified.get_nth_parent_hash(h, min(5, self.verified.get_height(h)))),
1027             #self.items[h].peer is None,
1028             -self.items[h].should_punish_reason(previous_block, bits, self, known_txs)[0],
1029             -self.items[h].time_seen,
1030         ), h) for h in self.verified.tails.get(best_tail, []))
1031         if p2pool.DEBUG:
1032             print len(decorated_heads), 'heads. Top 10:'
1033             for score, head_hash in decorated_heads[-10:]:
1034                 print '   ', format_hash(head_hash), format_hash(self.items[head_hash].previous_hash), score
1035         best_head_score, best = decorated_heads[-1] if decorated_heads else (None, None)
1036
1037         if best is not None:
1038             best_share = self.items[best]
1039             punish, punish_reason = best_share.should_punish_reason(previous_block, bits, self, known_txs)
1040             if punish > 0:
1041                 print 'Punishing share for %r! Jumping from %s to %s!' % (punish_reason, format_hash(best), format_hash(best_share.previous_hash))
1042                 best = best_share.previous_hash
1043
1044             timestamp_cutoff = min(int(time.time()), best_share.timestamp) - 3600
1045             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
1046         else:
1047             timestamp_cutoff = int(time.time()) - 24*60*60
1048             target_cutoff = 2**256-1
1049
1050         if p2pool.DEBUG:
1051             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))
1052             for peer, hash, ts, targ in desired:
1053                 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
1054
1055         return best, [(peer, hash) for peer, hash, ts, targ in desired if ts >= timestamp_cutoff], decorated_heads
1056
1057     def score(self, share_hash, block_rel_height_func):
1058         # returns approximate lower bound on chain's hashrate in the last self.net.CHAIN_LENGTH*15//16*self.net.SHARE_PERIOD time
1059
1060         head_height = self.verified.get_height(share_hash)
1061         if head_height < self.net.CHAIN_LENGTH:
1062             return head_height, None
1063
1064         end_point = self.verified.get_nth_parent_hash(share_hash, self.net.CHAIN_LENGTH*15//16)
1065
1066         block_height = max(block_rel_height_func(share.header['previous_block']) for share in
1067             self.verified.get_chain(end_point, self.net.CHAIN_LENGTH//16))
1068
1069         return self.net.CHAIN_LENGTH, self.verified.get_delta(share_hash, end_point).work//((0 - block_height + 1)*self.net.PARENT.BLOCK_PERIOD)
1070
1071 def get_pool_attempts_per_second(tracker, previous_share_hash, dist, min_work=False, integer=False):
1072     assert dist >= 2
1073     near = tracker.items[previous_share_hash]
1074     far = tracker.items[tracker.get_nth_parent_hash(previous_share_hash, dist - 1)]
1075     attempts = tracker.get_delta(near.hash, far.hash).work if not min_work else tracker.get_delta(near.hash, far.hash).min_work
1076     time = near.timestamp - far.timestamp
1077     if time <= 0:
1078         time = 1
1079     if integer:
1080         return attempts//time
1081     return attempts/time
1082
1083 def get_average_stale_prop(tracker, share_hash, lookbehind):
1084     stales = sum(1 for share in tracker.get_chain(share_hash, lookbehind) if share.share_data['stale_info'] is not None)
1085     return stales/(lookbehind + stales)
1086
1087 def get_stale_counts(tracker, share_hash, lookbehind, rates=False):
1088     res = {}
1089     for share in tracker.get_chain(share_hash, lookbehind - 1):
1090         res['good'] = res.get('good', 0) + bitcoin_data.target_to_average_attempts(share.target)
1091         s = share.share_data['stale_info']
1092         if s is not None:
1093             res[s] = res.get(s, 0) + bitcoin_data.target_to_average_attempts(share.target)
1094     if rates:
1095         dt = tracker.items[share_hash].timestamp - tracker.items[tracker.get_nth_parent_hash(share_hash, lookbehind - 1)].timestamp
1096         res = dict((k, v/dt) for k, v in res.iteritems())
1097     return res
1098
1099 def get_user_stale_props(tracker, share_hash, lookbehind):
1100     res = {}
1101     for share in tracker.get_chain(share_hash, lookbehind - 1):
1102         stale, total = res.get(share.share_data['pubkey_hash'], (0, 0))
1103         total += 1
1104         if share.share_data['stale_info'] is not None:
1105             stale += 1
1106             total += 1
1107         res[share.share_data['pubkey_hash']] = stale, total
1108     return dict((pubkey_hash, stale/total) for pubkey_hash, (stale, total) in res.iteritems())
1109
1110 def get_expected_payouts(tracker, best_share_hash, block_target, subsidy, net):
1111     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))
1112     res = dict((script, subsidy*weight//total_weight) for script, weight in weights.iteritems())
1113     res[DONATION_SCRIPT] = res.get(DONATION_SCRIPT, 0) + subsidy - sum(res.itervalues())
1114     return res
1115
1116 def get_desired_version_counts(tracker, best_share_hash, dist):
1117     res = {}
1118     for share in tracker.get_chain(best_share_hash, dist):
1119         res[share.desired_version] = res.get(share.desired_version, 0) + bitcoin_data.target_to_average_attempts(share.target)
1120     return res
1121
1122 def get_warnings(tracker, best_share, net, bitcoind_warning, bitcoind_work_value):
1123     res = []
1124
1125     desired_version_counts = get_desired_version_counts(tracker, best_share,
1126         min(net.CHAIN_LENGTH, 60*60//net.SHARE_PERIOD, tracker.get_height(best_share)))
1127     majority_desired_version = max(desired_version_counts, key=lambda k: desired_version_counts[k])
1128     if majority_desired_version > NewNewShare.VERSION and desired_version_counts[majority_desired_version] > sum(desired_version_counts.itervalues())/2:
1129         res.append('A MAJORITY OF SHARES CONTAIN A VOTE FOR AN UNSUPPORTED SHARE IMPLEMENTATION! (v%i with %i%% support)\n'
1130             'An upgrade is likely necessary. Check http://p2pool.forre.st/ for more information.' % (
1131                 majority_desired_version, 100*desired_version_counts[majority_desired_version]/sum(desired_version_counts.itervalues())))
1132
1133     if bitcoind_warning is not None:
1134         if 'This is a pre-release test build' not in bitcoind_warning:
1135             res.append('(from bitcoind) %s' % (bitcoind_warning,))
1136
1137     if time.time() > bitcoind_work_value['last_update'] + 60:
1138         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']),))
1139
1140     return res
1141
1142 def format_hash(x):
1143     if x is None:
1144         return 'xxxxxxxx'
1145     return '%08x' % (x % 2**32)
1146
1147 class ShareStore(object):
1148     def __init__(self, prefix, net):
1149         self.filename = prefix
1150         self.dirname = os.path.dirname(os.path.abspath(prefix))
1151         self.filename = os.path.basename(os.path.abspath(prefix))
1152         self.net = net
1153         self.known = None # will be filename -> set of share hashes, set of verified hashes
1154         self.known_desired = None
1155
1156     def get_shares(self):
1157         if self.known is not None:
1158             raise AssertionError()
1159         known = {}
1160         filenames, next = self.get_filenames_and_next()
1161         for filename in filenames:
1162             share_hashes, verified_hashes = known.setdefault(filename, (set(), set()))
1163             with open(filename, 'rb') as f:
1164                 for line in f:
1165                     try:
1166                         type_id_str, data_hex = line.strip().split(' ')
1167                         type_id = int(type_id_str)
1168                         if type_id == 0:
1169                             pass
1170                         elif type_id == 1:
1171                             pass
1172                         elif type_id == 2:
1173                             verified_hash = int(data_hex, 16)
1174                             yield 'verified_hash', verified_hash
1175                             verified_hashes.add(verified_hash)
1176                         elif type_id == 5:
1177                             raw_share = share_type.unpack(data_hex.decode('hex'))
1178                             if raw_share['type'] in [0, 1, 2, 3, 6, 7]:
1179                                 continue
1180                             share = load_share(raw_share, self.net, None)
1181                             yield 'share', share
1182                             share_hashes.add(share.hash)
1183                         else:
1184                             raise NotImplementedError("share type %i" % (type_id,))
1185                     except Exception:
1186                         log.err(None, "HARMLESS error while reading saved shares, continuing where left off:")
1187         self.known = known
1188         self.known_desired = dict((k, (set(a), set(b))) for k, (a, b) in known.iteritems())
1189
1190     def _add_line(self, line):
1191         filenames, next = self.get_filenames_and_next()
1192         if filenames and os.path.getsize(filenames[-1]) < 10e6:
1193             filename = filenames[-1]
1194         else:
1195             filename = next
1196
1197         with open(filename, 'ab') as f:
1198             f.write(line + '\n')
1199
1200         return filename
1201
1202     def add_share(self, share):
1203         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
1204             if share.hash in share_hashes:
1205                 break
1206         else:
1207             filename = self._add_line("%i %s" % (5, share_type.pack(share.as_share()).encode('hex')))
1208             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
1209             share_hashes.add(share.hash)
1210         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
1211         share_hashes.add(share.hash)
1212
1213     def add_verified_hash(self, share_hash):
1214         for filename, (share_hashes, verified_hashes) in self.known.iteritems():
1215             if share_hash in verified_hashes:
1216                 break
1217         else:
1218             filename = self._add_line("%i %x" % (2, share_hash))
1219             share_hashes, verified_hashes = self.known.setdefault(filename, (set(), set()))
1220             verified_hashes.add(share_hash)
1221         share_hashes, verified_hashes = self.known_desired.setdefault(filename, (set(), set()))
1222         verified_hashes.add(share_hash)
1223
1224     def get_filenames_and_next(self):
1225         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())
1226         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)))
1227
1228     def forget_share(self, share_hash):
1229         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1230             if share_hash in share_hashes:
1231                 share_hashes.remove(share_hash)
1232         self.check_remove()
1233
1234     def forget_verified_share(self, share_hash):
1235         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1236             if share_hash in verified_hashes:
1237                 verified_hashes.remove(share_hash)
1238         self.check_remove()
1239
1240     def check_remove(self):
1241         to_remove = set()
1242         for filename, (share_hashes, verified_hashes) in self.known_desired.iteritems():
1243             #print filename, len(share_hashes) + len(verified_hashes)
1244             if not share_hashes and not verified_hashes:
1245                 to_remove.add(filename)
1246         for filename in to_remove:
1247             self.known.pop(filename)
1248             self.known_desired.pop(filename)
1249             os.remove(filename)
1250             print "REMOVED", filename