work
[p2pool.git] / p2pool / data.py
1 from __future__ import division
2
3 import itertools
4 import traceback
5
6 from p2pool.util import math
7 from p2pool.bitcoin import data as bitcoin_data
8
9 class CompressedList(bitcoin_data.Type):
10     def __init__(self, inner):
11         self.inner = inner
12     
13     def read(self, file):
14         values, file = bitcoin_data.ListType(self.inner).read(file)
15         if values != sorted(set(values)):
16             raise ValueError("invalid values")
17         references, file = bitcoin_data.ListType(bitcoin_data.VarIntType()).read(file)
18         return [values[reference] for reference in references], file
19     
20     def write(self, file, item):
21         values = sorted(set(item))
22         values_map = dict((value, i) for i, value in enumerate(values))
23         file = bitcoin_data.ListType(self.inner).write(file, values)
24         return bitcoin_data.ListType(bitcoin_data.VarIntType()).write(file, [values_map[subitem] for subitem in item])
25
26
27 merkle_branch_type = bitcoin_data.ListType(bitcoin_data.ComposedType([
28     ('side', bitcoin_data.StructType('<B')), # enum?
29     ('hash', bitcoin_data.HashType()),
30 ]))
31
32
33 share_data_type = bitcoin_data.ComposedType([
34     ('previous_share_hash', bitcoin_data.PossiblyNone(0, bitcoin_data.HashType())),
35     ('previous_shares_hash', bitcoin_data.HashType()),
36     ('target2', bitcoin_data.FloatingIntegerType()),
37     ('nonce', bitcoin_data.VarStrType()),
38 ])
39
40
41 coinbase_type = bitcoin_data.ComposedType([
42     ('identifier', bitcoin_data.FixedStrType(8)),
43     ('share_data', share_data_type),
44 ])
45
46 share_info_type = bitcoin_data.ComposedType([
47     ('share_data', share_data_type),
48     ('new_script', bitcoin_data.VarStrType()),
49     ('subsidy', bitcoin_data.StructType('<Q')),
50 ])
51
52
53 share1a_type = bitcoin_data.ComposedType([
54     ('header', bitcoin_data.block_header_type), # merkle_header not completely needed
55     ('share_info', share_info_type),
56     ('merkle_branch', merkle_branch_type),
57 ])
58
59 share1b_type = bitcoin_data.ComposedType([
60     ('header', bitcoin_data.block_header_type),
61     ('share_info', share_info_type),
62     ('other_txs', bitcoin_data.ListType(bitcoin_data.tx_type)),
63 ])
64
65 shares_type = CompressedList(bitcoin_data.VarStrType())
66
67 def calculate_merkle_branch(txs, index):
68     hash_list = [(bitcoin_data.tx_type.hash256(tx), i == index, []) for i, tx in enumerate(txs)]
69     
70     while len(hash_list) > 1:
71         hash_list = [
72             (
73                 bitcoin_data.merkle_record_type.hash256(dict(left=left, right=right)),
74                 left_f or right_f,
75                 (left_l if left_f else right_l) + [dict(side=1, hash=right) if left_f else dict(side=0, hash=left)],
76             )
77             for (left, left_f, left_l), (right, right_f, right_l) in
78                 zip(hash_list[::2], hash_list[1::2] + [hash_list[::2][-1]])
79         ]
80     
81     assert hash_list[0][1]
82     assert check_merkle_branch(txs[index], hash_list[0][2]) == hash_list[0][0]
83     
84     return hash_list[0][2]
85
86 def check_merkle_branch(tx, branch):
87     hash_ = bitcoin_data.tx_type.hash256(tx)
88     for step in branch:
89         if not step['side']:
90             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=step['hash'], right=hash_))
91         else:
92             hash_ = bitcoin_data.merkle_record_type.hash256(dict(left=hash_, right=step['hash']))
93     return hash_
94
95 def gentx_to_share_info(gentx):
96     return dict(
97         share_data=coinbase_type.unpack(gentx['tx_ins'][0]['script'])['share_data'],
98         subsidy=sum(tx_out['value'] for tx_out in gentx['tx_outs']),
99         new_script=gentx['tx_outs'][-1]['script'],
100     )
101
102 def share_info_to_gentx(share_info, block_target, tracker, net):
103     return generate_transaction(
104         tracker=tracker,
105         previous_share_hash=share_info['share_data']['previous_share_hash'],
106         new_script=share_info['new_script'],
107         subsidy=share_info['subsidy'],
108         nonce=share_info['share_data']['nonce'],
109         block_target=block_target,
110         net=net,
111     )
112
113 class Share(object):
114     peer = None
115     
116     @classmethod
117     def from_block(cls, block):
118         return cls(block['header'], gentx_to_share_info(block['txs'][0]), other_txs=block['txs'][1:])
119     
120     @classmethod
121     def from_share1a(cls, share1a):
122         return cls(**share1a)
123     
124     @classmethod
125     def from_share1b(cls, share1b):
126         return cls(**share1b)
127     
128     def __init__(self, header, share_info, merkle_branch=None, other_txs=None):
129         if merkle_branch is None and other_txs is None:
130             raise ValueError('need either merkle_branch or other_txs')
131         
132         self.header = header
133         self.share_info = share_info
134         self.merkle_branch = merkle_branch
135         self.other_txs = other_txs
136         
137         self.timestamp = self.header['timestamp']
138         
139         self.share_data = self.share_info['share_data']
140         self.new_script = self.share_info['new_script']
141         self.subsidy = self.share_info['subsidy']
142         
143         self.previous_hash = self.previous_share_hash = self.share_data['previous_share_hash']
144         self.previous_shares_hash = self.share_data['previous_shares_hash']
145         self.target2 = self.share_data['target2']
146         
147         self.hash = bitcoin_data.block_header_type.hash256(header)
148         
149         if self.hash > self.target2:
150             print "hash", hex(self.hash)
151             print "targ", hex(self.target2)
152             raise ValueError('not enough work!')
153         
154         
155         self.shared = False
156     
157     def as_block(self):
158         if self.txs is None:
159             raise ValueError('share does not contain all txs')
160         
161         return dict(header=self.header, txs=self.txs)
162     
163     def as_share1a(self):
164         return dict(header=self.header, share_info=self.share_info, merkle_branch=self.merkle_branch)
165     
166     def as_share1b(self):
167         return dict(header=self.header, share_info=self.share_info, other_txs=self.other_txs)
168     
169     def check(self, tracker, net):
170         gentx = share_info_to_gentx(self.share_info, self.header['target'], tracker, net)
171         
172         if self.merkle_branch is not None:
173             if check_merkle_branch(gentx, self.merkle_branch) != self.header['merkle_root']:
174                 raise ValueError("gentx doesn't match header via merkle_branch")
175         
176         if self.other_txs is not None:
177             if bitcoin_data.merkle_hash([gentx] + self.other_txs) != self.header['merkle_root']:
178                 raise ValueError("gentx doesn't match header via other_txs")
179         
180         return Share2(self)
181     
182     def flag_shared(self):
183         self.shared = True
184     
185     def __repr__(self):
186         return '<Share %s>' % (' '.join('%s=%r' % (k, v) for k, v in self.__dict__.iteritems()),)
187
188 class Share2(object):
189     '''Share with associated data'''
190     
191     def __init__(self, share):
192         self.share = share
193         
194         self.shared = False
195     
196     def flag_shared(self):
197         self.shared = True
198
199 def generate_transaction(tracker, previous_share_hash, new_script, subsidy, nonce, block_target, net):
200     previous_share2 = tracker.shares[previous_share_hash] if previous_share_hash is not None else None
201     #previous_share2 = chain.shares
202     #previous_shares
203     #shares = 
204     #shares = (previous_share2.shares if previous_share2 is not None else [net.SCRIPT]*net.SPREAD)[1:-1] + [new_script, new_script]
205     
206     lookbehind = 120
207     chain = list(itertools.islice(tracker.get_chain_to_root(previous_share_hash), lookbehind))
208     if len(chain) < lookbehind:
209         target2 = bitcoin_data.FloatingIntegerType().truncate_to(2**256//2**16 - 1)
210     else:
211         attempts = sum(bitcoin_data.target_to_average_attempts(share.target2) for share in chain)
212         time = chain[0].timestamp - chain[-1].timestamp
213         if time == 0:
214             time = 1
215         attempts_per_second = attempts//time
216         pre_target = 2**256//(net.SHARE_PERIOD*attempts_per_second) - 1
217         pre_target2 = math.clip(pre_target, (previous_share2.target2*9//10, previous_share2.target2*11//10))
218         pre_target3 = math.clip(pre_target2, (0, 2**256//2**16 - 1))
219         target2 = bitcoin_data.FloatingIntegerType().truncate_to(pre_target3)
220         print attempts_per_second//1000, "KHASH"
221         print "TARGET", 2**256//target2, 2**256/pre_target
222         print "ATT", bitcoin_data.target_to_average_attempts(target2)//1000
223     
224     
225     attempts_to_block = bitcoin_data.target_to_average_attempts(block_target)
226     max_weight = net.SPREAD * attempts_to_block
227     total_weight = 0
228     
229     class fake_share(object):
230         script = new_script
231         share = dict(target=target2)
232     
233     dest_weights = {}
234     for i, share in enumerate(itertools.chain([fake_share], itertools.islice(tracker.get_chain_to_root(previous_share_hash), net.CHAIN_LENGTH))):
235         weight = bitcoin_data.target_to_average_attempts(share.share['target'])
236         weight = max(weight, max_weight - total_weight)
237         
238         dest_weights[share.script] = dest_weights.get(share.script, 0) + weight
239         total_weight += weight
240         
241         if total_weight == max_weight:
242             break
243     
244     amounts = dict((script, subsidy*(199*weight)//(200*total_weight)) for (script, weight) in dest_weights.iteritems())
245     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy*1//200
246     amounts[net.SCRIPT] = amounts.get(net.SCRIPT, 0) + subsidy - sum(amounts.itervalues()) # collect any extra
247     
248     dests = sorted(amounts.iterkeys(), key=lambda script: (script == new_script, script))
249     assert dests[-1] == new_script
250     
251     previous_shares = [] # XXX
252     
253     return dict(
254         version=1,
255         tx_ins=[dict(
256             previous_output=None,
257             sequence=None,
258             script=coinbase_type.pack(dict(
259                 identifier=net.IDENTIFIER,
260                 share_data=dict(
261                     previous_share_hash=previous_share_hash,
262                     previous_shares_hash=shares_type.hash256(previous_shares),
263                     nonce=nonce,
264                     target2=target2,
265                 ),
266             )),
267         )],
268         tx_outs=[dict(value=amounts[script], script=script) for script in dests if amounts[script]],
269         lock_time=0,
270     )
271
272
273
274
275 if __name__ == '__main__':
276     class FakeShare(object):
277         def __init__(self, hash, previous_share_hash):
278             self.hash = hash
279             self.previous_share_hash = previous_share_hash
280     
281     t = Tracker()
282     
283     t.add_share(FakeShare(1, 2))
284     print t.heads, t.tails
285     t.add_share(FakeShare(4, 0))
286     print t.heads, t.tails
287     t.add_share(FakeShare(3, 4))
288     print t.heads, t.tails
289     t.add_share(FakeShare(5, 0))
290     print t.heads, t.tails
291     t.add_share(FakeShare(0, 1))
292     print t.heads, t.tails
293     
294     for share_hash in t.shares:
295         print share_hash, t.get_height_and_last(share_hash)
296
297 class OkayTracker(bitcoin_data.Tracker):
298     def __init__(self, net):
299         bitcoin_data.Tracker.__init__(self)
300         self.net = net
301         self.verified = bitcoin_data.Tracker()
302     """
303         self.okay_cache = {} # hash -> height
304     
305     def is_okay(self, start, _height_after=0):
306         '''
307         Returns:
308             {'result': 'okay', verified_height: ...} # if share has an okay parent or if share has CHAIN_LENGTH children and CHAIN_LENTH parents that it verified with
309             {'result': 'needs_share', 'share_hash': ...} # if share doesn't have CHAIN_LENGTH parents
310             #{'result': 'needs_share_shares', 'share_hash': ...} # if share has CHAIN_LENGTH children and needs its shares to 
311             {'result': 'not_okay'} # if the share has a not okay parent or if the share has an okay parent and failed validation
312         '''
313         
314         if start in self.okay_cache:
315             return dict(result='okay', verified_height=self.okay_cache['start'])
316         
317         share = self.shares[start]
318         if start not in self.shares:
319             return dict(result='needs_share', share_hash=start)
320         
321         length = len
322         to_end_rev = []
323         for share in itertools.islice(self.get_chain(start), self.net.CHAIN_LENGTH):
324             if share in self.okay_cache:
325                 return validate(share, to_end_rev[::-1])
326             to_end_rev.append(share)
327         # picking up last share from for loop, ew
328         self.okay_cache.add(share)
329         return validate(share, to_end_rev[::-1])
330     """
331     def think(self):
332         desired = set()
333         
334         # for each overall head, attempt verification
335         # if it fails, attempt on parent, and repeat
336         # if no successful verification because of lack of parents, request parent
337         for head in self.heads:
338             head_height, last = self.get_height_and_last(head)
339             if head_height < self.net.CHAIN_LENGTH and last is not None:
340                 # request more
341                 pass
342             
343             for share in itertools.islice(self.get_chain_known(head), None if last is None else head_height - self.net.CHAIN_LENGTH): # XXX change length for None
344                 if share.hash in self.verified.shares:
345                     break
346                 print share
347                 try:
348                     share.check(self, self.net)
349                 except:
350                     print
351                     print "Share check failed:"
352                     traceback.print_exc()
353                     print
354                 else:
355                     self.verified.add(share)
356                     break
357         
358         # try to get at least CHAIN_LENGTH height for each verified head, requesting parents if needed
359         for head in self.verified.heads:
360             head_height, last = self.verified.get_height_and_last(head)
361             if head_height < self.net.CHAIN_LENGTH and last is not None:
362                 desired.add(last)
363         
364         # decide best verified head
365         def score(share_hash):
366             share = self.verified.shares[share_hash]
367             head_height, last = self.verified.get_height_and_last(share)
368             RECENTNESS = 0
369             return (min(head_height, self.net.CHAIN_LENGTH), RECENTNESS)
370         best = max(self.verified.heads, key=score) if self.verified.heads else None
371         
372         return best, desired
373
374
375 class Mainnet(bitcoin_data.Mainnet):
376     SHARE_PERIOD = 5 # seconds
377     CHAIN_LENGTH = 24*60*60//5 # shares
378     SPREAD = 3 # blocks
379     SCRIPT = '4104ffd03de44a6e11b9917f3a29f9443283d9871c9d743ef30d5eddcd37094b64d1b3d8090496b53256786bf5c82932ec23c3b74d9f05a6f95a8b5529352656664bac'.decode('hex')
380     IDENTIFIER = '7452839666e1f8f8'.decode('hex')
381     PREFIX = '2d4224bf18c87b87'.decode('hex')
382     ADDRS_TABLE = 'addrs'
383     P2P_PORT = 9333
384
385 class Testnet(bitcoin_data.Testnet):
386     SHARE_PERIOD = 5 # seconds
387     CHAIN_LENGTH = 24*60*60//5 # shares
388     SPREAD = 3 # blocks
389     SCRIPT = '410403ad3dee8ab3d8a9ce5dd2abfbe7364ccd9413df1d279bf1a207849310465b0956e5904b1155ecd17574778f9949589ebfd4fb33ce837c241474a225cf08d85dac'.decode('hex')
390     IDENTIFIER = '1ae3479e4eb6700a'.decode('hex')
391     PREFIX = 'd19778c812754854'.decode('hex')
392     ADDRS_TABLE = 'addrs_testnet'
393     P2P_PORT = 19333