1 files changed, 21 insertions, 26 deletions

diff --git a/nizk/stage1.go b/nizk/stage1.go
index 3ebed27..07eba3f 100644
--- a/nizk/stage1.go
+++ b/nizk/stage1.go
@@ -1,8 +1,6 @@
 package nizk
 
 import (
-	"fmt"
-
 	. "kesim.org/seal/common"
 )
 
@@ -36,14 +34,13 @@ type Stage1Proof struct {
 }
 
 func (b *Bit) stage(x, r *Scalar) {
-	b.Commit() // ensure non-null values for A, B, C
 	b.Stage = &Stage{
 		x: x,
 		r: r,
 	}
 }
 
-func (s *Stage) commit(Xs ...*Point) *StageCommitment {
+func (s *Stage) commit() *StageCommitment {
 	if s.StageCommitment != nil {
 		return s.StageCommitment
 	}
@@ -55,22 +52,22 @@ func (s *Stage) commit(Xs ...*Point) *StageCommitment {
 	return s.StageCommitment
 }
 
-func (b *Bit) StageCommit(Xs ...*Point) (s *StageCommitment) {
+func (b *Bit) StageCommit() (s *StageCommitment) {
+	if b.Stage != nil {
+		return b.Stage.StageCommitment
+	}
 	x := Curve.RandomScalar()
 	r := Curve.RandomScalar()
-	return b.StageFromScalars(x, r, Xs...)
+	return b.StageFromScalars(x, r)
 }
 
-func (b *Bit) StageFromScalars(x, r *Scalar, Xs ...*Point) (c *StageCommitment) {
+func (b *Bit) StageFromScalars(x, r *Scalar) (c *StageCommitment) {
 	b.stage(x, r)
-	return b.Stage.commit(Xs...)
+	return b.Stage.commit()
 }
 
-func (b *Bit) reveal(prev_true bool, Xs ...*Point) (r *StageReveal, e error) {
+func (b *Bit) reveal(prev_true bool, Xs ...*Point) (r *StageReveal) {
 	s := b.Stage
-	if s == nil {
-		return nil, fmt.Errorf("stage not ready")
-	}
 
 	// TODO: Calculate Y based on the Xs and our own X_i
 	// as Π_(i<k) X_k / Π_(i>k) X_k
@@ -85,14 +82,15 @@ func (b *Bit) reveal(prev_true bool, Xs ...*Point) (r *StageReveal, e error) {
 		r.Z = Y.Exp(s.x)
 	}
 
-	return r, e
+	return r
 }
 
-func (b *Bit) RevealStage1(Xs ...*Point) (rev *StageReveal, pr *Stage1Proof, e error) {
-	s := b.Stage
-	if s == nil {
-		return nil, nil, fmt.Errorf("stage not ready")
+func (b *Bit) RevealStage1(Xs ...*Point) (rev *StageReveal, pr *Stage1Proof) {
+	if b.Stage == nil {
+		b.StageCommit()
 	}
+	s := b.Stage
+
 	var ε [2][4]*Point
 	var r1, r2, ρ1, ρ2, ω *Scalar
 	for _, s := range []**Scalar{&r1, &r2, &ρ1, &ρ2, &ω} {
@@ -100,10 +98,7 @@ func (b *Bit) RevealStage1(Xs ...*Point) (rev *StageReveal, pr *Stage1Proof, e e
 	}
 	c := s.commit()
 
-	rev, e = b.reveal(true, Xs...)
-	if e != nil {
-		return nil, nil, e
-	}
+	rev = b.reveal(true, Xs...)
 
 	if b.IsSet() {
 		ε[0][0] = G.Exp(r1).Mul(c.X.Exp(ω))
@@ -126,11 +121,11 @@ func (b *Bit) RevealStage1(Xs ...*Point) (rev *StageReveal, pr *Stage1Proof, e e
 	}
 
 	p := []Bytes{G, b.A, b.B, b.C, c.R, c.X, rev.Y, rev.Z}
-	for _, e := range ε[0] {
-		p = append(p, e)
+	for _, ε := range ε[0] {
+		p = append(p, ε)
 	}
-	for _, e := range ε[1] {
-		p = append(p, e)
+	for _, ε := range ε[1] {
+		p = append(p, ε)
 	}
 
 	ch := Challenge(p...)
@@ -153,7 +148,7 @@ func (b *Bit) RevealStage1(Xs ...*Point) (rev *StageReveal, pr *Stage1Proof, e e
 	}
 
 	s.StageReveal = rev
-	return rev, pr, e
+	return rev, pr
 }
 
 func (c *Commitment) VerifyStage1(sc *StageCommitment, r *StageReveal, p *Stage1Proof) bool {