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zcash-test-vectors
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Fix compilation bugs in Pedersen hash

This commit is contained in:
Jack Grigg 2018-05-18 16:40:21 +12:00
parent 2f152758ba
commit ce7c7cfb39
1 changed files with 4 additions and 3 deletions
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7
sapling_pedersen.py
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@ -1,6 +1,6 @@
#!/usr/bin/env python3
from sapling_generators import find_group_hash, NOTE_POSITION_BASE, WINDOWED_PEDERSEN_RANDOMNESS_BASE
from sapling_jubjub import Fr
from sapling_jubjub import Fr, Point
from sapling_utils import cldiv, i2leosp
@ -16,7 +16,7 @@ def encode_chunk(mj):
return (1 - 2*s2) * (1 + s0 + 2*s1)
def encode_segment(Mi):
ki = len(Mi) / 3
ki = len(Mi) // 3
Michunks = [Mi[i:i+3] for i in range(0, len(Mi), 3)]
assert(len(Michunks) == ki)
return Fr(sum([encode_chunk(Michunks[j-1]) * 2**(4*(j-1)) for j in range(1, ki + 1)]))
@ -26,10 +26,11 @@ c = 63
def pedersen_hash_to_point(D, M):
# Pad M to a multiple of 3 bits
Mdash = M + [0] * ((-len(M)) % 3)
assert((len(Mdash) // 3) * 3 == len(Mdash))
n = cldiv(len(Mdash), 3 * c)
Msegs = [Mdash[i:i+(3*c)] for i in range(0, len(Mdash), 3*c)]
assert(len(Msegs) == n)
return sum([I_D_i(D, i) * encode_segment(Msegs[i-1]) for i in range(1, n + 1)])
return sum([I_D_i(D, i) * encode_segment(Msegs[i-1]) for i in range(1, n + 1)], Point.ZERO)
def pedersen_hash(D, M):
return pedersen_hash_to_point(D, M).u.bits(255)