X-Git-Url: https://git.novaco.in/?a=blobdiff_plain;f=p2pool%2Fbitcoin%2Fdata.py;h=74cb94bb7bc51986c4a9dd6ddda9fb0b862e1aa6;hb=f732111a6e08d7d0649c330d1c703535a8ea80b5;hp=d4643a2a85be33b7da78f26b4869ec35bea9bfe0;hpb=f3ac11fe31222cb37395d142b5861753b3e36ae5;p=p2pool.git

diff --git a/p2pool/bitcoin/data.py b/p2pool/bitcoin/data.py
index d4643a2..74cb94b 100644
--- a/p2pool/bitcoin/data.py
+++ b/p2pool/bitcoin/data.py
@@ -1,520 +1,307 @@
 from __future__ import division
 
 import hashlib
-import itertools
-import struct
+import random
+import warnings
 
-from twisted.internet import defer
-
-from . import base58, skiplists
-from p2pool.util import bases, math, variable, expiring_dict, memoize, dicts
 import p2pool
+from p2pool.util import math, pack
 
-class EarlyEnd(Exception):
-    pass
-
-class LateEnd(Exception):
-    pass
+def hash256(data):
+    return pack.IntType(256).unpack(hashlib.sha256(hashlib.sha256(data).digest()).digest())
 
-def read((data, pos), length):
-    data2 = data[pos:pos + length]
-    if len(data2) != length:
-        raise EarlyEnd()
-    return data2, (data, pos + length)
+def hash160(data):
+    return pack.IntType(160).unpack(hashlib.new('ripemd160', hashlib.sha256(data).digest()).digest())
 
-def size((data, pos)):
-    return len(data) - pos
+def scrypt(data):
+    return pack.IntType(256).unpack(__import__('ltc_scrypt').getPoWHash(data))
 
-class Type(object):
-    # the same data can have only one unpacked representation, but multiple packed binary representations
-    
-    def __hash__(self):
-        rval = getattr(self, '_hash', None)
-        if rval is None:
-            try:
-                rval = self._hash = hash((type(self), frozenset(self.__dict__.items())))
-            except:
-                print self.__dict__
-                raise
-        return rval
-    
-    def __eq__(self, other):
-        return type(other) is type(self) and other.__dict__ == self.__dict__
-    
-    def __ne__(self, other):
-        return not (self == other)
-    
-    def _unpack(self, data):
-        obj, (data2, pos) = self.read((data, 0))
-        
-        assert data2 is data
-        
-        if pos != len(data):
-            raise LateEnd()
-        
-        return obj
-    
-    def _pack(self, obj):
-        f = self.write(None, obj)
-        
-        res = []
-        while f is not None:
-            res.append(f[1])
-            f = f[0]
-        res.reverse()
-        return ''.join(res)
-    
-    
-    def unpack(self, data):
-        obj = self._unpack(data)
-        
-        if p2pool.DEBUG:
-            data2 = self._pack(obj)
-            if data2 != data:
-                if self._unpack(data2) != obj:
-                    raise AssertionError()
-        
-        return obj
-    
-    def pack2(self, obj):
-        data = self._pack(obj)
-        
-        if p2pool.DEBUG:
-            if self._unpack(data) != obj:
-                raise AssertionError((self._unpack(data), obj))
-        
-        return data
-    
-    _backing = expiring_dict.ExpiringDict(100)
-    pack2 = memoize.memoize_with_backing(_backing, [unpack])(pack2)
-    unpack = memoize.memoize_with_backing(_backing)(unpack) # doesn't have an inverse
-    
-    def pack(self, obj):
-        return self.pack2(dicts.immutify(obj))
-    
-    
-    def pack_base58(self, obj):
-        return base58.base58_encode(self.pack(obj))
-    
-    def unpack_base58(self, base58_data):
-        return self.unpack(base58.base58_decode(base58_data))
-    
-    
-    def hash160(self, obj):
-        return ShortHashType().unpack(hashlib.new('ripemd160', hashlib.sha256(self.pack(obj)).digest()).digest())
-    
-    def hash256(self, obj):
-        return HashType().unpack(hashlib.sha256(hashlib.sha256(self.pack(obj)).digest()).digest())
-    
-    def scrypt(self, obj):
-        import ltc_scrypt
-        return HashType().unpack(self.ltc_scrypt.getPoWHash(self.pack(obj)))
-
-class VarIntType(Type):
-    # redundancy doesn't matter here because bitcoin and p2pool both reencode before hashing
-    def read(self, file):
-        data, file = read(file, 1)
-        first = ord(data)
-        if first < 0xfd:
-            return first, file
-        elif first == 0xfd:
-            desc, length = '<H', 2
-        elif first == 0xfe:
-            desc, length = '<I', 4
-        elif first == 0xff:
-            desc, length = '<Q', 8
-        else:
-            raise AssertionError()
-        data, file = read(file, length)
-        return struct.unpack(desc, data)[0], file
-    
-    def write(self, file, item):
-        if item < 0xfd:
-            file = file, struct.pack('<B', item)
-        elif item <= 0xffff:
-            file = file, struct.pack('<BH', 0xfd, item)
-        elif item <= 0xffffffff:
-            file = file, struct.pack('<BI', 0xfe, item)
-        elif item <= 0xffffffffffffffff:
-            file = file, struct.pack('<BQ', 0xff, item)
-        else:
-            raise ValueError('int too large for varint')
-        return file
-
-class VarStrType(Type):
-    _inner_size = VarIntType()
-    
-    def read(self, file):
-        length, file = self._inner_size.read(file)
-        return read(file, length)
-    
-    def write(self, file, item):
-        return self._inner_size.write(file, len(item)), item
-
-class FixedStrType(Type):
-    def __init__(self, length):
-        self.length = length
-    
-    def read(self, file):
-        return read(file, self.length)
-    
-    def write(self, file, item):
-        if len(item) != self.length:
-            raise ValueError('incorrect length item!')
-        return file, item
-
-class EnumType(Type):
-    def __init__(self, inner, values):
-        self.inner = inner
-        self.values = dicts.frozendict(values)
-        
-        keys = {}
-        for k, v in values.iteritems():
-            if v in keys:
-                raise ValueError('duplicate value in values')
-            keys[v] = k
-        self.keys = dicts.frozendict(keys)
-    
-    def read(self, file):
-        data, file = self.inner.read(file)
-        if data not in self.keys:
-            raise ValueError('enum data (%r) not in values (%r)' % (data, self.values))
-        return self.keys[data], file
-    
-    def write(self, file, item):
-        if item not in self.values:
-            raise ValueError('enum item (%r) not in values (%r)' % (item, self.values))
-        return self.inner.write(file, self.values[item])
-
-class HashType(Type):
-    def read(self, file):
-        data, file = read(file, 256//8)
-        return int(data[::-1].encode('hex'), 16), file
-    
-    def write(self, file, item):
-        if not 0 <= item < 2**256:
-            raise ValueError('invalid hash value - %r' % (item,))
-        if item != 0 and item < 2**160:
-            print 'Very low hash value - maybe you meant to use ShortHashType? %x' % (item,)
-        return file, ('%064x' % (item,)).decode('hex')[::-1]
-
-class ShortHashType(Type):
-    def read(self, file):
-        data, file = read(file, 160//8)
-        return int(data[::-1].encode('hex'), 16), file
-    
-    def write(self, file, item):
-        if not 0 <= item < 2**160:
-            raise ValueError('invalid hash value - %r' % (item,))
-        return file, ('%040x' % (item,)).decode('hex')[::-1]
-
-class ListType(Type):
-    _inner_size = VarIntType()
-    
-    def __init__(self, type):
-        self.type = type
-    
-    def read(self, file):
-        length, file = self._inner_size.read(file)
-        res = []
-        for i in xrange(length):
-            item, file = self.type.read(file)
-            res.append(item)
-        return res, file
-    
-    def write(self, file, item):
-        file = self._inner_size.write(file, len(item))
-        for subitem in item:
-            file = self.type.write(file, subitem)
-        return file
-
-class StructType(Type):
-    def __init__(self, desc):
-        self.desc = desc
-        self.length = struct.calcsize(self.desc)
-    
-    def read(self, file):
-        data, file = read(file, self.length)
-        res, = struct.unpack(self.desc, data)
-        return res, file
-    
-    def write(self, file, item):
-        data = struct.pack(self.desc, item)
-        if struct.unpack(self.desc, data)[0] != item:
-            # special test because struct doesn't error on some overflows
-            raise ValueError('''item didn't survive pack cycle (%r)''' % (item,))
-        return file, data
-
-class IPV6AddressType(Type):
-    def read(self, file):
-        data, file = read(file, 16)
-        if data[:12] != '00000000000000000000ffff'.decode('hex'):
-            raise ValueError('ipv6 addresses not supported yet')
-        return '.'.join(str(ord(x)) for x in data[12:]), file
-    
-    def write(self, file, item):
-        bits = map(int, item.split('.'))
-        if len(bits) != 4:
-            raise ValueError('invalid address: %r' % (bits,))
-        data = '00000000000000000000ffff'.decode('hex') + ''.join(chr(x) for x in bits)
-        assert len(data) == 16, len(data)
-        return file, data
-
-_record_types = {}
-
-def get_record(fields):
-    fields = tuple(sorted(fields))
-    if 'keys' in fields:
-        raise ValueError()
-    if fields not in _record_types:
-        class _Record(object):
-            __slots__ = fields
-            def __repr__(self):
-                return repr(dict(self))
-            def __getitem__(self, key):
-                return getattr(self, key)
-            def __setitem__(self, key, value):
-                setattr(self, key, value)
-            #def __iter__(self):
-            #    for field in self.__slots__:
-            #        yield field, getattr(self, field)
-            def keys(self):
-                return self.__slots__
-            def __eq__(self, other):
-                if isinstance(other, dict):
-                    return dict(self) == other
-                elif isinstance(other, _Record):
-                    return all(self[k] == other[k] for k in self.keys())
-                raise TypeError()
-            def __ne__(self, other):
-                return not (self == other)
-        _record_types[fields] = _Record
-    return _record_types[fields]()
-
-class ComposedType(Type):
-    def __init__(self, fields):
-        self.fields = tuple(fields)
-    
-    def read(self, file):
-        item = get_record(k for k, v in self.fields)
-        for key, type_ in self.fields:
-            item[key], file = type_.read(file)
-        return item, file
-    
-    def write(self, file, item):
-        for key, type_ in self.fields:
-            file = type_.write(file, item[key])
-        return file
-
-class ChecksummedType(Type):
-    def __init__(self, inner):
+class ChecksummedType(pack.Type):
+    def __init__(self, inner, checksum_func=lambda data: hashlib.sha256(hashlib.sha256(data).digest()).digest()[:4]):
         self.inner = inner
+        self.checksum_func = checksum_func
     
     def read(self, file):
         obj, file = self.inner.read(file)
         data = self.inner.pack(obj)
         
-        checksum, file = read(file, 4)
-        if checksum != hashlib.sha256(hashlib.sha256(data).digest()).digest()[:4]:
+        calculated_checksum = self.checksum_func(data)
+        checksum, file = pack.read(file, len(calculated_checksum))
+        if checksum != calculated_checksum:
             raise ValueError('invalid checksum')
         
         return obj, file
     
     def write(self, file, item):
         data = self.inner.pack(item)
-        return (file, data), hashlib.sha256(hashlib.sha256(data).digest()).digest()[:4]
+        return (file, data), self.checksum_func(data)
 
 class FloatingInteger(object):
-    __slots__ = ['_bits']
+    __slots__ = ['bits', '_target']
     
     @classmethod
     def from_target_upper_bound(cls, target):
-        n = bases.natural_to_string(target)
+        n = math.natural_to_string(target)
         if n and ord(n[0]) >= 128:
             n = '\x00' + n
         bits2 = (chr(len(n)) + (n + 3*chr(0))[:3])[::-1]
-        bits = struct.unpack('<I', bits2)[0]
+        bits = pack.IntType(32).unpack(bits2)
         return cls(bits)
     
-    def __init__(self, bits):
-        self._bits = bits
+    def __init__(self, bits, target=None):
+        self.bits = bits
+        self._target = None
+        if target is not None and self.target != target:
+            raise ValueError('target does not match')
     
     @property
-    def _value(self):
-        return math.shift_left(self._bits & 0x00ffffff, 8 * ((self._bits >> 24) - 3))
+    def target(self):
+        res = self._target
+        if res is None:
+            res = self._target = math.shift_left(self.bits & 0x00ffffff, 8 * ((self.bits >> 24) - 3))
+        return res
     
     def __hash__(self):
-        return hash(self._value)
+        return hash(self.bits)
     
-    def __cmp__(self, other):
-        if isinstance(other, FloatingInteger):
-            return cmp(self._value, other._value)
-        elif isinstance(other, (int, long)):
-            return cmp(self._value, other)
-        else:
-            raise NotImplementedError()
+    def __eq__(self, other):
+        return self.bits == other.bits
     
-    def __int__(self):
-        return self._value
+    def __ne__(self, other):
+        return not (self == other)
     
-    def __repr__(self):
-        return 'FloatingInteger(bits=%s (%x))' % (hex(self._bits), self)
+    def __cmp__(self, other):
+        assert False
     
-    def __add__(self, other):
-        if isinstance(other, (int, long)):
-            return self._value + other
-        raise NotImplementedError()
-    __radd__ = __add__
-    def __mul__(self, other):
-        if isinstance(other, (int, long)):
-            return self._value * other
-        raise NotImplementedError()
-    __rmul__ = __mul__
-    def __truediv__(self, other):
-        if isinstance(other, (int, long)):
-            return self._value / other
-        raise NotImplementedError()
-    def __floordiv__(self, other):
-        if isinstance(other, (int, long)):
-            return self._value // other
-        raise NotImplementedError()
-    __div__ = __truediv__
-    def __rtruediv__(self, other):
-        if isinstance(other, (int, long)):
-            return other / self._value
-        raise NotImplementedError()
-    def __rfloordiv__(self, other):
-        if isinstance(other, (int, long)):
-            return other // self._value
-        raise NotImplementedError()
-    __rdiv__ = __rtruediv__
-
-class FloatingIntegerType(Type):
-    _inner = StructType('<I')
+    def __repr__(self):
+        return 'FloatingInteger(bits=%s, target=%s)' % (hex(self.bits), hex(self.target))
+
+class FloatingIntegerType(pack.Type):
+    _inner = pack.IntType(32)
     
     def read(self, file):
         bits, file = self._inner.read(file)
         return FloatingInteger(bits), file
     
     def write(self, file, item):
-        return self._inner.write(file, item._bits)
+        return self._inner.write(file, item.bits)
 
-class PossiblyNoneType(Type):
-    def __init__(self, none_value, inner):
-        self.none_value = none_value
-        self.inner = inner
-    
-    def read(self, file):
-        value, file = self.inner.read(file)
-        return None if value == self.none_value else value, file
-    
-    def write(self, file, item):
-        if item == self.none_value:
-            raise ValueError('none_value used')
-        return self.inner.write(file, self.none_value if item is None else item)
-
-address_type = ComposedType([
-    ('services', StructType('<Q')),
-    ('address', IPV6AddressType()),
-    ('port', StructType('>H')),
+address_type = pack.ComposedType([
+    ('services', pack.IntType(64)),
+    ('address', pack.IPV6AddressType()),
+    ('port', pack.IntType(16, 'big')),
 ])
 
-tx_type = ComposedType([
-    ('version', StructType('<I')),
-    ('tx_ins', ListType(ComposedType([
-        ('previous_output', PossiblyNoneType(dicts.frozendict(hash=0, index=2**32 - 1), ComposedType([
-            ('hash', HashType()),
-            ('index', StructType('<I')),
+tx_type = pack.ComposedType([
+    ('version', pack.IntType(32)),
+    ('timestamp', pack.IntType(32)), # txn timestamp
+    ('tx_ins', pack.ListType(pack.ComposedType([
+        ('previous_output', pack.PossiblyNoneType(dict(hash=0, index=2**32 - 1), pack.ComposedType([
+            ('hash', pack.IntType(256)),
+            ('index', pack.IntType(32)),
         ]))),
-        ('script', VarStrType()),
-        ('sequence', PossiblyNoneType(2**32 - 1, StructType('<I'))),
+        ('script', pack.VarStrType()),
+        ('sequence', pack.PossiblyNoneType(2**32 - 1, pack.IntType(32))),
     ]))),
-    ('tx_outs', ListType(ComposedType([
-        ('value', StructType('<Q')),
-        ('script', VarStrType()),
+    ('tx_outs', pack.ListType(pack.ComposedType([
+        ('value', pack.IntType(64)),
+        ('script', pack.VarStrType()),
     ]))),
-    ('lock_time', StructType('<I')),
+    ('lock_time', pack.IntType(32)),
+])
+
+merkle_link_type = pack.ComposedType([
+    ('branch', pack.ListType(pack.IntType(256))),
+    ('index', pack.IntType(32)),
 ])
 
-merkle_tx_type = ComposedType([
+merkle_tx_type = pack.ComposedType([
     ('tx', tx_type),
-    ('block_hash', HashType()),
-    ('merkle_branch', ListType(HashType())),
-    ('index', StructType('<i')),
+    ('block_hash', pack.IntType(256)),
+    ('merkle_link', merkle_link_type),
 ])
 
-block_header_type = ComposedType([
-    ('version', StructType('<I')),
-    ('previous_block', PossiblyNoneType(0, HashType())),
-    ('merkle_root', HashType()),
-    ('timestamp', StructType('<I')),
-    ('target', FloatingIntegerType()),
-    ('nonce', StructType('<I')),
+block_header_type = pack.ComposedType([
+    ('version', pack.IntType(32)),
+    ('previous_block', pack.PossiblyNoneType(0, pack.IntType(256))),
+    ('merkle_root', pack.IntType(256)),
+    ('timestamp', pack.IntType(32)),
+    ('bits', FloatingIntegerType()),
+    ('nonce', pack.IntType(32)),
 ])
 
-block_type = ComposedType([
+block_type = pack.ComposedType([
     ('header', block_header_type),
-    ('txs', ListType(tx_type)),
+    ('txs', pack.ListType(tx_type)),
+    ('signature', pack.VarStrType()), # header signature field
 ])
 
-aux_pow_type = ComposedType([
+# merged mining
+
+aux_pow_type = pack.ComposedType([
     ('merkle_tx', merkle_tx_type),
-    ('merkle_branch', ListType(HashType())),
-    ('index', StructType('<i')),
+    ('merkle_link', merkle_link_type),
     ('parent_block_header', block_header_type),
 ])
 
+aux_pow_coinbase_type = pack.ComposedType([
+    ('merkle_root', pack.IntType(256, 'big')),
+    ('size', pack.IntType(32)),
+    ('nonce', pack.IntType(32)),
+])
+
+def make_auxpow_tree(chain_ids):
+    for size in (2**i for i in xrange(31)):
+        if size < len(chain_ids):
+            continue
+        res = {}
+        for chain_id in chain_ids:
+            pos = (1103515245 * chain_id + 1103515245 * 12345 + 12345) % size
+            if pos in res:
+                break
+            res[pos] = chain_id
+        else:
+            return res, size
+    raise AssertionError()
+
+# merkle trees
 
-merkle_record_type = ComposedType([
-    ('left', HashType()),
-    ('right', HashType()),
+merkle_record_type = pack.ComposedType([
+    ('left', pack.IntType(256)),
+    ('right', pack.IntType(256)),
 ])
 
-def merkle_hash(tx_list):
-    if not tx_list:
+def merkle_hash(hashes):
+    if not hashes:
         return 0
-    hash_list = map(tx_type.hash256, tx_list)
+    hash_list = list(hashes)
     while len(hash_list) > 1:
-        hash_list = [merkle_record_type.hash256(dict(left=left, right=left if right is None else right))
-            for left, right in zip(hash_list[::2], hash_list[1::2] + [None])]
+        hash_list = [hash256(merkle_record_type.pack(dict(left=left, right=right)))
+            for left, right in zip(hash_list[::2], hash_list[1::2] + [hash_list[::2][-1]])]
     return hash_list[0]
 
+def calculate_merkle_link(hashes, index):
+    # XXX optimize this
+    
+    hash_list = [(lambda _h=h: _h, i == index, []) for i, h in enumerate(hashes)]
+    
+    while len(hash_list) > 1:
+        hash_list = [
+            (
+                lambda _left=left, _right=right: hash256(merkle_record_type.pack(dict(left=_left(), right=_right()))),
+                left_f or right_f,
+                (left_l if left_f else right_l) + [dict(side=1, hash=right) if left_f else dict(side=0, hash=left)],
+            )
+            for (left, left_f, left_l), (right, right_f, right_l) in
+                zip(hash_list[::2], hash_list[1::2] + [hash_list[::2][-1]])
+        ]
+    
+    res = [x['hash']() for x in hash_list[0][2]]
+    
+    assert hash_list[0][1]
+    if p2pool.DEBUG:
+        new_hashes = [random.randrange(2**256) if x is None else x
+            for x in hashes]
+        assert check_merkle_link(new_hashes[index], dict(branch=res, index=index)) == merkle_hash(new_hashes)
+    assert index == sum(k*2**i for i, k in enumerate([1-x['side'] for x in hash_list[0][2]]))
+    
+    return dict(branch=res, index=index)
+
+def check_merkle_link(tip_hash, link):
+    if link['index'] >= 2**len(link['branch']):
+        raise ValueError('index too large')
+    return reduce(lambda c, (i, h): hash256(merkle_record_type.pack(
+        dict(left=h, right=c) if (link['index'] >> i) & 1 else
+        dict(left=c, right=h)
+    )), enumerate(link['branch']), tip_hash)
+
+# targets
+
 def target_to_average_attempts(target):
+    assert 0 <= target and isinstance(target, (int, long)), target
+    if target >= 2**256: warnings.warn('target >= 2**256!')
     return 2**256//(target + 1)
 
-# tx
+def average_attempts_to_target(average_attempts):
+    assert average_attempts > 0
+    return min(int(2**256/average_attempts - 1 + 0.5), 2**256-1)
+
+def target_to_difficulty(target):
+    assert 0 <= target and isinstance(target, (int, long)), target
+    if target >= 2**256: warnings.warn('target >= 2**256!')
+    return (0xffff0000 * 2**(256-64) + 1)/(target + 1)
 
-def tx_get_sigop_count(tx):
-    return sum(script.get_sigop_count(txin['script']) for txin in tx['tx_ins']) + sum(script.get_sigop_count(txout['script']) for txout in tx['tx_outs'])
+def difficulty_to_target(difficulty):
+    assert difficulty >= 0
+    if difficulty == 0: return 2**256-1
+    return min(int((0xffff0000 * 2**(256-64) + 1)/difficulty - 1 + 0.5), 2**256-1)
 
 # human addresses
 
-human_address_type = ChecksummedType(ComposedType([
-    ('version', StructType('<B')),
-    ('pubkey_hash', ShortHashType()),
-]))
+base58_alphabet = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
+
+def base58_encode(bindata):
+    bindata2 = bindata.lstrip(chr(0))
+    return base58_alphabet[0]*(len(bindata) - len(bindata2)) + math.natural_to_string(math.string_to_natural(bindata2), base58_alphabet)
+
+def base58_decode(b58data):
+    b58data2 = b58data.lstrip(base58_alphabet[0])
+    return chr(0)*(len(b58data) - len(b58data2)) + math.natural_to_string(math.string_to_natural(b58data2, base58_alphabet))
 
-pubkey_type = FixedStrType(65)
+human_address_type = ChecksummedType(pack.ComposedType([
+    ('version', pack.IntType(8)),
+    ('pubkey_hash', pack.IntType(160)),
+]))
 
 def pubkey_hash_to_address(pubkey_hash, net):
-    return human_address_type.pack_base58(dict(version=net.BITCOIN_ADDRESS_VERSION, pubkey_hash=pubkey_hash))
+    return base58_encode(human_address_type.pack(dict(version=net.ADDRESS_VERSION, pubkey_hash=pubkey_hash)))
 
 def pubkey_to_address(pubkey, net):
-    return pubkey_hash_to_address(pubkey_type.hash160(pubkey), net)
+    return pubkey_hash_to_address(hash160(pubkey), net)
 
 def address_to_pubkey_hash(address, net):
-    x = human_address_type.unpack_base58(address)
-    if x['version'] != net.BITCOIN_ADDRESS_VERSION:
+    x = human_address_type.unpack(base58_decode(address))
+    if x['version'] != net.ADDRESS_VERSION:
         raise ValueError('address not for this net!')
     return x['pubkey_hash']
 
+def address_to_script(address, net):
+    x = human_address_type.unpack(base58_decode(address))
+
+    print x['pubkey_hash']
+
+    if x['version'] != net.ADDRESS_VERSION:
+        raise ValueError('address not for this net!')
+    return '\x76\xa9' + ('\x14' + pack.IntType(160).pack(x['pubkey_hash'])) + '\x88\xac'
+
+
 # transactions
 
 def pubkey_to_script2(pubkey):
-    return ('\x41' + pubkey_type.pack(pubkey)) + '\xac'
+    assert len(pubkey) <= 75
+    return (chr(len(pubkey)) + pubkey) + '\xac'
 
 def pubkey_hash_to_script2(pubkey_hash):
-    return '\x76\xa9' + ('\x14' + ShortHashType().pack(pubkey_hash)) + '\x88\xac'
+    return '\x76\xa9' + ('\x14' + pack.IntType(160).pack(pubkey_hash)) + '\x88\xac'
+
+def script2_to_address(script2, net):
+    try:
+        pubkey = script2[1:-1]
+        script2_test = pubkey_to_script2(pubkey)
+    except:
+        pass
+    else:
+        if script2_test == script2:
+            return pubkey_to_address(pubkey, net)
+    
+    try:
+        pubkey_hash = pack.IntType(160).unpack(script2[3:-2])
+        script2_test2 = pubkey_hash_to_script2(pubkey_hash)
+    except:
+        pass
+    else:
+        if script2_test2 == script2:
+            return pubkey_hash_to_address(pubkey_hash, net)
 
 def script2_to_human(script2, net):
     try:
@@ -527,7 +314,7 @@ def script2_to_human(script2, net):
             return 'Pubkey. Address: %s' % (pubkey_to_address(pubkey, net),)
     
     try:
-        pubkey_hash = ShortHashType().unpack(script2[3:-2])
+        pubkey_hash = pack.IntType(160).unpack(script2[3:-2])
         script2_test2 = pubkey_hash_to_script2(pubkey_hash)
     except:
         pass
@@ -536,305 +323,3 @@ def script2_to_human(script2, net):
             return 'Address. Address: %s' % (pubkey_hash_to_address(pubkey_hash, net),)
     
     return 'Unknown. Script: %s'  % (script2.encode('hex'),)
-
-# linked list tracker
-
-class Tracker(object):
-    def __init__(self):
-        self.shares = {} # hash -> share
-        #self.ids = {} # hash -> (id, height)
-        self.reverse_shares = {} # previous_hash -> set of share_hashes
-        
-        self.heads = {} # head hash -> tail_hash
-        self.tails = {} # tail hash -> set of head hashes
-        
-        self.heights = {} # share_hash -> height_to, ref, work_inc
-        self.reverse_heights = {} # ref -> set of share_hashes
-        
-        self.ref_generator = itertools.count()
-        self.height_refs = {} # ref -> height, share_hash, work_inc
-        self.reverse_height_refs = {} # share_hash -> ref
-        
-        self.get_nth_parent_hash = skiplists.DistanceSkipList(self)
-        
-        self.added = variable.Event()
-        self.removed = variable.Event()
-    
-    def add(self, share):
-        assert not isinstance(share, (int, long, type(None)))
-        if share.hash in self.shares:
-            raise ValueError('share already present')
-        
-        if share.hash in self.tails:
-            heads = self.tails.pop(share.hash)
-        else:
-            heads = set([share.hash])
-        
-        if share.previous_hash in self.heads:
-            tail = self.heads.pop(share.previous_hash)
-        else:
-            tail = self.get_last(share.previous_hash)
-            #tail2 = share.previous_hash
-            #while tail2 in self.shares:
-            #    tail2 = self.shares[tail2].previous_hash
-            #assert tail == tail2
-        
-        self.shares[share.hash] = share
-        self.reverse_shares.setdefault(share.previous_hash, set()).add(share.hash)
-        
-        self.tails.setdefault(tail, set()).update(heads)
-        if share.previous_hash in self.tails[tail]:
-            self.tails[tail].remove(share.previous_hash)
-        
-        for head in heads:
-            self.heads[head] = tail
-        
-        self.added.happened(share)
-    
-    def test(self):
-        t = Tracker()
-        for s in self.shares.itervalues():
-            t.add(s)
-        
-        assert self.shares == t.shares, (self.shares, t.shares)
-        assert self.reverse_shares == t.reverse_shares, (self.reverse_shares, t.reverse_shares)
-        assert self.heads == t.heads, (self.heads, t.heads)
-        assert self.tails == t.tails, (self.tails, t.tails)
-    
-    def remove(self, share_hash):
-        assert isinstance(share_hash, (int, long, type(None)))
-        if share_hash not in self.shares:
-            raise KeyError()
-        
-        share = self.shares[share_hash]
-        del share_hash
-        
-        children = self.reverse_shares.get(share.hash, set())
-        
-        # move height refs referencing children down to this, so they can be moved up in one step
-        if share.previous_hash in self.reverse_height_refs:
-            if share.previous_hash not in self.tails:
-                for x in list(self.reverse_heights.get(self.reverse_height_refs.get(share.previous_hash, object()), set())):
-                    self.get_last(x)
-            for x in list(self.reverse_heights.get(self.reverse_height_refs.get(share.hash, object()), set())):
-                self.get_last(x)
-            assert share.hash not in self.reverse_height_refs, list(self.reverse_heights.get(self.reverse_height_refs.get(share.hash, None), set()))
-        
-        if share.hash in self.heads and share.previous_hash in self.tails:
-            tail = self.heads.pop(share.hash)
-            self.tails[tail].remove(share.hash)
-            if not self.tails[share.previous_hash]:
-                self.tails.pop(share.previous_hash)
-        elif share.hash in self.heads:
-            tail = self.heads.pop(share.hash)
-            self.tails[tail].remove(share.hash)
-            if self.reverse_shares[share.previous_hash] != set([share.hash]):
-                pass # has sibling
-            else:
-                self.tails[tail].add(share.previous_hash)
-                self.heads[share.previous_hash] = tail
-        elif share.previous_hash in self.tails:
-            heads = self.tails[share.previous_hash]
-            if len(self.reverse_shares[share.previous_hash]) > 1:
-                raise NotImplementedError()
-            else:
-                del self.tails[share.previous_hash]
-                for head in heads:
-                    self.heads[head] = share.hash
-                self.tails[share.hash] = set(heads)
-        else:
-            raise NotImplementedError()
-        
-        # move ref pointing to this up
-        if share.previous_hash in self.reverse_height_refs:
-            assert share.hash not in self.reverse_height_refs, list(self.reverse_heights.get(self.reverse_height_refs.get(share.hash, object()), set()))
-            
-            ref = self.reverse_height_refs[share.previous_hash]
-            cur_height, cur_hash, cur_work = self.height_refs[ref]
-            assert cur_hash == share.previous_hash
-            self.height_refs[ref] = cur_height - 1, share.hash, cur_work - target_to_average_attempts(share.target)
-            del self.reverse_height_refs[share.previous_hash]
-            self.reverse_height_refs[share.hash] = ref
-        
-        # delete height entry, and ref if it is empty
-        if share.hash in self.heights:
-            _, ref, _ = self.heights.pop(share.hash)
-            self.reverse_heights[ref].remove(share.hash)
-            if not self.reverse_heights[ref]:
-                del self.reverse_heights[ref]
-                _, ref_hash, _ = self.height_refs.pop(ref)
-                del self.reverse_height_refs[ref_hash]
-        
-        self.shares.pop(share.hash)
-        self.reverse_shares[share.previous_hash].remove(share.hash)
-        if not self.reverse_shares[share.previous_hash]:
-            self.reverse_shares.pop(share.previous_hash)
-        
-        #assert self.test() is None
-        self.removed.happened(share)
-    
-    def get_height(self, share_hash):
-        height, work, last = self.get_height_work_and_last(share_hash)
-        return height
-    
-    def get_work(self, share_hash):
-        height, work, last = self.get_height_work_and_last(share_hash)
-        return work
-    
-    def get_last(self, share_hash):
-        height, work, last = self.get_height_work_and_last(share_hash)
-        return last
-    
-    def get_height_and_last(self, share_hash):
-        height, work, last = self.get_height_work_and_last(share_hash)
-        return height, last
-    
-    def _get_height_jump(self, share_hash):
-        if share_hash in self.heights:
-            height_to1, ref, work_inc1 = self.heights[share_hash]
-            height_to2, share_hash, work_inc2 = self.height_refs[ref]
-            height_inc = height_to1 + height_to2
-            work_inc = work_inc1 + work_inc2
-        else:
-            height_inc, share_hash, work_inc = 1, self.shares[share_hash].previous_hash, target_to_average_attempts(self.shares[share_hash].target)
-        return height_inc, share_hash, work_inc
-    
-    def _set_height_jump(self, share_hash, height_inc, other_share_hash, work_inc):
-        if other_share_hash not in self.reverse_height_refs:
-            ref = self.ref_generator.next()
-            assert ref not in self.height_refs
-            self.height_refs[ref] = 0, other_share_hash, 0
-            self.reverse_height_refs[other_share_hash] = ref
-            del ref
-        
-        ref = self.reverse_height_refs[other_share_hash]
-        ref_height_to, ref_share_hash, ref_work_inc = self.height_refs[ref]
-        assert ref_share_hash == other_share_hash
-        
-        if share_hash in self.heights:
-            prev_ref = self.heights[share_hash][1]
-            self.reverse_heights[prev_ref].remove(share_hash)
-            if not self.reverse_heights[prev_ref] and prev_ref != ref:
-                self.reverse_heights.pop(prev_ref)
-                _, x, _ = self.height_refs.pop(prev_ref)
-                self.reverse_height_refs.pop(x)
-        self.heights[share_hash] = height_inc - ref_height_to, ref, work_inc - ref_work_inc
-        self.reverse_heights.setdefault(ref, set()).add(share_hash)
-    
-    def get_height_work_and_last(self, share_hash):
-        assert isinstance(share_hash, (int, long, type(None)))
-        orig = share_hash
-        height = 0
-        work = 0
-        updates = []
-        while share_hash in self.shares:
-            updates.append((share_hash, height, work))
-            height_inc, share_hash, work_inc = self._get_height_jump(share_hash)
-            height += height_inc
-            work += work_inc
-        for update_hash, height_then, work_then in updates:
-            self._set_height_jump(update_hash, height - height_then, share_hash, work - work_then)
-        return height, work, share_hash
-    
-    def get_chain_known(self, start_hash):
-        assert isinstance(start_hash, (int, long, type(None)))
-        '''
-        Chain starting with item of hash I{start_hash} of items that this Tracker contains
-        '''
-        item_hash_to_get = start_hash
-        while True:
-            if item_hash_to_get not in self.shares:
-                break
-            share = self.shares[item_hash_to_get]
-            assert not isinstance(share, long)
-            yield share
-            item_hash_to_get = share.previous_hash
-    
-    def get_chain_to_root(self, start_hash, root=None):
-        assert isinstance(start_hash, (int, long, type(None)))
-        assert isinstance(root, (int, long, type(None)))
-        '''
-        Chain of hashes starting with share_hash of shares to the root (doesn't include root)
-        Raises an error if one is missing
-        '''
-        share_hash_to_get = start_hash
-        while share_hash_to_get != root:
-            share = self.shares[share_hash_to_get]
-            yield share
-            share_hash_to_get = share.previous_hash
-    
-    def get_best_hash(self):
-        '''
-        Returns hash of item with the most items in its chain
-        '''
-        if not self.heads:
-            return None
-        return max(self.heads, key=self.get_height_and_last)
-    
-    def get_highest_height(self):
-        return max(self.get_height_and_last(head)[0] for head in self.heads) if self.heads else 0
-    
-    def is_child_of(self, share_hash, possible_child_hash):
-        height, last = self.get_height_and_last(share_hash)
-        child_height, child_last = self.get_height_and_last(possible_child_hash)
-        if child_last != last:
-            return None # not connected, so can't be determined
-        height_up = child_height - height
-        return height_up >= 0 and self.get_nth_parent_hash(possible_child_hash, height_up) == share_hash
-
-class FakeShare(object):
-    def __init__(self, **kwargs):
-        self.__dict__.update(kwargs)
-
-if __name__ == '__main__':
-    
-    t = Tracker()
-    
-    for i in xrange(10000):
-        t.add(FakeShare(hash=i, previous_hash=i - 1 if i > 0 else None))
-    
-    #t.remove(99)
-    
-    print 'HEADS', t.heads
-    print 'TAILS', t.tails
-    
-    import random
-    
-    while False:
-        print
-        print '-'*30
-        print
-        t = Tracker()
-        for i in xrange(random.randrange(100)):
-            x = random.choice(list(t.shares) + [None])
-            print i, '->', x
-            t.add(FakeShare(i, x))
-        while t.shares:
-            x = random.choice(list(t.shares))
-            print 'DEL', x, t.__dict__
-            try:
-                t.remove(x)
-            except NotImplementedError:
-                print 'aborted; not implemented'
-        import time
-        time.sleep(.1)
-        print 'HEADS', t.heads
-        print 'TAILS', t.tails
-    
-    #for share_hash, share in sorted(t.shares.iteritems()):
-    #    print share_hash, share.previous_hash, t.heads.get(share_hash), t.tails.get(share_hash)
-    
-    #import sys;sys.exit()
-    
-    print t.get_nth_parent_hash(9000, 5000)
-    print t.get_nth_parent_hash(9001, 412)
-    #print t.get_nth_parent_hash(90, 51)
-    
-    for share_hash in sorted(t.shares):
-        print str(share_hash).rjust(4),
-        x = t.skips.get(share_hash, None)
-        if x is not None:
-            print str(x[0]).rjust(4),
-            for a in x[1]:
-                print str(a).rjust(10),
-        print