45 lines
1015 B
Python
45 lines
1015 B
Python
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#! /usr/bin/env python
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import sys
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import bitcoin
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alphabet = '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz'
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def b58dec(word):
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x = 0
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for c in word:
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x *= 58
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x += alphabet.find(c)
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return x
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def asciidec(val):
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word = []
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while val > 0:
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word.append(val % 256)
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val /= 256
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return word[-1::-1]
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if __name__ == '__main__':
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prefix = sys.argv[1]
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length = int(sys.argv[2])
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target = b58dec(prefix)
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shift = 8*(length+4)
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for m in range(1,1000):
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lo = target * 58**m
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lo = (lo >> shift) + (0 if lo == ((lo >> shift) << shift) else 1)
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hi = (target + 1) * 58**m - (1 << shift) +1
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hi = hi >> shift
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if hi >= lo:
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# test
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for bt in '\x00\xff':
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s = bitcoin.bin_to_b58check(bt * length, magicbyte=lo)
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assert s.startswith(prefix)
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assert len(s) == m + len(prefix)
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print m + len(prefix), lo, asciidec(lo)
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exit(0)
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