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Upgrade linters

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arnaucube
2020-12-16 15:04:43 +01:00
parent 821a601d20
commit 6d75396b4b
14 changed files with 203 additions and 113 deletions
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46
babyjub/babyjub.go
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@@ -59,7 +59,8 @@ type PointProjective struct {
// NewPointProjective creates a new Point in projective coordinates.
func NewPointProjective() *PointProjective {
return &PointProjective{X: ff.NewElement().SetZero(), Y: ff.NewElement().SetOne(), Z: ff.NewElement().SetOne()}
return &PointProjective{X: ff.NewElement().SetZero(),
Y: ff.NewElement().SetOne(), Z: ff.NewElement().SetOne()}
}
// Affine returns the Point from the projective representation
@@ -84,19 +85,21 @@ func (p *PointProjective) Affine() *Point {
}
}
// Add computes the addition of two points in projective coordinates representation
func (res *PointProjective) Add(p *PointProjective, q *PointProjective) *PointProjective {
// add-2008-bbjlp https://hyperelliptic.org/EFD/g1p/auto-twisted-projective.html#doubling-dbl-2008-bbjlp
a := ff.NewElement().Mul(p.Z, q.Z)
// Add computes the addition of two points in projective coordinates
// representation
func (p *PointProjective) Add(q *PointProjective, o *PointProjective) *PointProjective {
// add-2008-bbjlp
// https://hyperelliptic.org/EFD/g1p/auto-twisted-projective.html#doubling-dbl-2008-bbjlp
a := ff.NewElement().Mul(q.Z, o.Z)
b := ff.NewElement().Square(a)
c := ff.NewElement().Mul(p.X, q.X)
d := ff.NewElement().Mul(p.Y, q.Y)
c := ff.NewElement().Mul(q.X, o.X)
d := ff.NewElement().Mul(q.Y, o.Y)
e := ff.NewElement().Mul(Dff, c)
e.MulAssign(d)
f := ff.NewElement().Sub(b, e)
g := ff.NewElement().Add(b, e)
x1y1 := ff.NewElement().Add(p.X, p.Y)
x2y2 := ff.NewElement().Add(q.X, q.Y)
x1y1 := ff.NewElement().Add(q.X, q.Y)
x2y2 := ff.NewElement().Add(o.X, o.Y)
x3 := ff.NewElement().Mul(x1y1, x2y2)
x3.SubAssign(c)
x3.SubAssign(d)
@@ -108,10 +111,10 @@ func (res *PointProjective) Add(p *PointProjective, q *PointProjective) *PointPr
y3.MulAssign(g)
z3 := ff.NewElement().Mul(f, g)
res.X = x3
res.Y = y3
res.Z = z3
return res
p.X = x3
p.Y = y3
p.Z = z3
return p
}
// Point represents a point of the babyjub curve.
@@ -141,15 +144,15 @@ func (p *Point) Projective() *PointProjective {
}
}
// Mul multiplies the Point p by the scalar s and stores the result in res,
// Mul multiplies the Point q by the scalar s and stores the result in p,
// which is also returned.
func (res *Point) Mul(s *big.Int, p *Point) *Point {
func (p *Point) Mul(s *big.Int, q *Point) *Point {
resProj := &PointProjective{
X: ff.NewElement().SetZero(),
Y: ff.NewElement().SetOne(),
Z: ff.NewElement().SetOne(),
}
exp := p.Projective()
exp := q.Projective()
for i := 0; i < s.BitLen(); i++ {
if s.Bit(i) == 1 {
@@ -157,8 +160,8 @@ func (res *Point) Mul(s *big.Int, p *Point) *Point {
}
exp = exp.Add(exp, exp)
}
res = resProj.Affine()
return res
p = resProj.Affine()
return p
}
// InCurve returns true when the Point p is in the babyjub curve.
@@ -200,10 +203,11 @@ func PointCoordSign(c *big.Int) bool {
return c.Cmp(new(big.Int).Rsh(constants.Q, 1)) == 1
}
// PackPoint packs a point into a 32 byte array
func PackPoint(ay *big.Int, sign bool) [32]byte {
leBuf := utils.BigIntLEBytes(ay)
if sign {
leBuf[31] = leBuf[31] | 0x80
leBuf[31] = leBuf[31] | 0x80 //nolint:gomnd
}
return leBuf
}
@@ -219,9 +223,9 @@ func (p *Point) Compress() [32]byte {
// Point. Returns error if the compressed Point is invalid.
func (p *Point) Decompress(leBuf [32]byte) (*Point, error) {
sign := false
if (leBuf[31] & 0x80) != 0x00 {
if (leBuf[31] & 0x80) != 0x00 { //nolint:gomnd
sign = true
leBuf[31] = leBuf[31] & 0x7F
leBuf[31] = leBuf[31] & 0x7F //nolint:gomnd
}
utils.SetBigIntFromLEBytes(p.Y, leBuf[:])
return PointFromSignAndY(sign, p.Y)