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Diffstat (limited to 'crypto/bn256/google/curve.go')
| -rw-r--r-- | crypto/bn256/google/curve.go | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/crypto/bn256/google/curve.go b/crypto/bn256/google/curve.go index 3e679fdc7..819cb81da 100644 --- a/crypto/bn256/google/curve.go +++ b/crypto/bn256/google/curve.go @@ -245,11 +245,19 @@ func (c *curvePoint) Mul(a *curvePoint, scalar *big.Int, pool *bnPool) *curvePoi return c } +// MakeAffine converts c to affine form and returns c. If c is ∞, then it sets +// c to 0 : 1 : 0. func (c *curvePoint) MakeAffine(pool *bnPool) *curvePoint { if words := c.z.Bits(); len(words) == 1 && words[0] == 1 { return c } - + if c.IsInfinity() { + c.x.SetInt64(0) + c.y.SetInt64(1) + c.z.SetInt64(0) + c.t.SetInt64(0) + return c + } zInv := pool.Get().ModInverse(c.z, P) t := pool.Get().Mul(c.y, zInv) t.Mod(t, P) |