p2pool/bitcoin/getwork.py

   1 '''
   2 Representation of a getwork request/reply
   3 '''
   4
   5 from __future__ import division
   6
   7 from . import data as bitcoin_data
   8 from . import sha256
   9 from p2pool.util import pack
  10
  11 def _swap4(s):
  12     if len(s) % 4:
  13         raise ValueError()
  14     return ''.join(s[x:x+4][::-1] for x in xrange(0, len(s), 4))
  15
  16 class BlockAttempt(object):
  17     def __init__(self, version, previous_block, merkle_root, timestamp, bits, share_target):
  18         self.version, self.previous_block, self.merkle_root, self.timestamp, self.bits, self.share_target = version, previous_block, merkle_root, timestamp, bits, share_target
  19
  20     def __hash__(self):
  21         return hash((self.version, self.previous_block, self.merkle_root, self.timestamp, self.bits, self.share_target))
  22
  23     def __eq__(self, other):
  24         if not isinstance(other, BlockAttempt):
  25             raise ValueError('comparisons only valid with other BlockAttempts')
  26         return self.__dict__ == other.__dict__
  27
  28     def __ne__(self, other):
  29         return not (self == other)
  30
  31     def __repr__(self):
  32         return 'BlockAttempt(%s)' % (', '.join('%s=%r' % (k, v) for k, v in self.__dict__.iteritems()),)
  33
  34     def getwork(self, _check=False, **extra):
  35         if 'data' in extra or 'hash1' in extra or 'target' in extra or 'midstate' in extra:
  36             raise ValueError()
  37
  38         block_data = bitcoin_data.block_header_type.pack(dict(
  39             version=self.version,
  40             previous_block=self.previous_block,
  41             merkle_root=self.merkle_root,
  42             timestamp=self.timestamp,
  43             bits=self.bits,
  44             nonce=0,
  45         ))
  46
  47         getwork = {
  48             'data': _swap4(block_data).encode('hex') + '000000800000000000000000000000000000000000000000000000000000000000000000000000000000000080020000',
  49             'hash1': '00000000000000000000000000000000000000000000000000000000000000000000008000000000000000000000000000000000000000000000000000010000',
  50             'target': pack.IntType(256).pack(self.share_target).encode('hex'),
  51             'midstate': _swap4(sha256.process(sha256.initial_state, block_data[:64])).encode('hex'),
  52         }
  53
  54         if _check:
  55             self_check = self.__class__.from_getwork(getwork, _check=False)
  56             if self_check != self:
  57                 raise AssertionError('failed check - input invalid or implementation error')
  58
  59         getwork = dict(getwork)
  60         getwork.update(extra)
  61
  62         return getwork
  63
  64     @classmethod
  65     def from_getwork(cls, getwork, _check=True):
  66         attrs = decode_data(getwork['data'])
  67
  68         ba = cls(
  69             version=attrs['version'],
  70             previous_block=attrs['previous_block'],
  71             merkle_root=attrs['merkle_root'],
  72             timestamp=attrs['timestamp'],
  73             bits=attrs['bits'],
  74             share_target=pack.IntType(256).unpack(getwork['target'].decode('hex')),
  75         )
  76
  77         if _check:
  78             extra = dict(getwork)
  79             del extra['data'], extra['hash1'], extra['target']
  80             extra.pop('midstate', None)
  81             getwork_check = ba.getwork(_check=False, **extra)
  82             if getwork_check != getwork and dict((k, v) for k, v in getwork_check.iteritems() if k != 'midstate') != getwork:
  83                 raise AssertionError('failed check - input invalid or implementation error')
  84
  85         return ba
  86
  87     def update(self, **kwargs):
  88         d = self.__dict__.copy()
  89         d.update(kwargs)
  90         return self.__class__(**d)
  91
  92 def decode_data(data):
  93     return bitcoin_data.block_header_type.unpack(_swap4(data.decode('hex'))[:80])