22 lines
529 B
Plaintext
Executable File
22 lines
529 B
Plaintext
Executable File
import "utils/pack/bool/nonStrictUnpack256" as unpack256;
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// Compress JubJub Curve Point to 256bit array using big endianness bit order
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// Python reference code from pycrypto:
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// def compress(self):
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// x = self.x.n
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// y = self.y.n
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// return int.to_bytes(y | ((x & 1) << 255), 32, "big")
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def main(field[2] pt) -> bool[256] {
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field x = pt[0];
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field y = pt[1];
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bool[256] xBits = unpack256(x);
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bool[256] mut yBits = unpack256(y);
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bool sign = xBits[255];
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yBits[0] = sign;
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return yBits;
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}
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