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package nizk
import (
"math/rand"
"slices"
"strings"
"sync"
"sync/atomic"
"testing"
. "kesim.org/seal/common"
)
type stage int
const (
stage1 stage = iota
stage2
)
func (s stage) String() string {
if s == stage1 {
return "stage1"
}
return "stage2"
}
func runVickrey(n int, bitlength int, tb testing.TB) {
var vals = make([]int, n)
var ids = make([]Bytes, n)
for i := range n {
vals[i] = rand.Intn(1<<(bitlength-1) - 1)
ids[i] = Curve.RandomScalar()
}
max := slices.Max(vals)
max_idx := slices.Index(vals, max)
max2 := slices.Max(slices.Delete(slices.Clone(vals), max_idx, max_idx+1))
if max == max2 {
max_idx = -1
}
tb.Logf("running vickrey for vals:\n%0[1]*[2]b\nmax: %0[1]*[3]b, max2: %0[1]*[4]b, winner: %d\n", bitlength, vals, max, max2, max_idx)
var bits = make([][]*Bit, n)
for i, b := range vals {
bits[i] = Int2Bits(ids[i], b, bitlength)
}
var c = make([]*StageCommitment, n)
var Xs = make([]*Point, n)
var r = make([]*StageReveal, n)
var p1 = make([]*Stage1Proof, n)
var Zs = make([]*Point, n)
var bj = make([]*Bit, n)
var p2 = make([]*Stage2Proof, n)
var lost = make([]bool, n)
stage := stage1
junction := -1
winner := -1
result := 0
isWinner := func(Z *Point, i int, idx int) bool {
z := Z.Div(Zs[i])
xu := Curve.Identity()
xl := Curve.Identity()
found := false
for k := range n {
if k == winner {
continue
}
if k < i {
xu = xu.Mul(Xs[k])
} else if k > i {
xl = xl.Mul(Xs[k])
}
}
xu = xu.Exp(bits[i][idx].Stage.x)
xl = xl.Exp(bits[i][idx].Stage.x)
x := xu.Div(xl)
if x.Equal(z) {
tb.Logf("equal by value")
found = true
}
if winner < 0 {
// BUG! TODO!
s1 := x.String()
s2 := z.String()
if strings.HasPrefix(s1, s2[:len(s2)-2]) {
tb.Logf("BUG! TODO! equal only by string")
found = true
}
}
// tb.Logf("testing max_idx %d, i %d, bit %d:\n%v vs %v", max_idx, i, idx, x, z)
return found
}
for idx := range bitlength {
for i := range n {
if i == winner {
c[i] = nil
bj[i] = nil
Xs[i] = Id
Zs[i] = Id
continue
}
c[i] = bits[i][idx].StageCommit()
Xs[i] = c[i].X
if stage == stage2 {
bj[i] = bits[i][junction]
}
}
var wg sync.WaitGroup
wg.Add(n)
fail := &atomic.Bool{}
for i := range n {
if i == winner {
tb.Logf("%s, idx: %d, skipping winner %d", stage, idx, winner)
wg.Done()
continue
}
go func(i int) {
defer wg.Done()
if stage == stage1 {
r[i], p1[i] = bits[i][idx].RevealStage1(Xs...)
if !bits[i][idx].Commitment.VerifyStage1(c[i], r[i], p1[i]) {
fail.Store(true)
tb.Fatalf("bits[i: %d][idx: %d] commitment failed to verify in stage1", i, idx)
}
} else {
r[i], p2[i] = bits[i][idx].RevealStage2(lost[i], bj[i], Xs...)
if !bits[i][idx].Commitment.VerifyStage2(bj[i].StageCommitment, c[i], bj[i].StageReveal, r[i], p2[i]) {
fail.Store(true)
tb.Fatalf("bits[i: %d][idx: %d] (junction: %d) verify failed in stage2, lost: %t, result so far: %05b\nXs: %v", i, idx, junction, lost[i], result, Xs)
}
}
Zs[i] = r[i].Z
}(i)
}
wg.Wait()
if fail.Load() {
tb.Fail()
return
}
Z := Curve.Product(Zs...)
tb.Logf("Z[idx: %d]: %v", idx, Z)
reset := false
if !Id.Equal(Z) {
var lost_round = make([]bool, n)
for i := range n {
if i == winner {
continue
}
if !lost[i] && !bits[i][idx].IsSet() {
lost_round[i] = true
}
// Winner test
if winner < 0 && !lost_round[i] && !lost[i] {
reset = isWinner(Z, i, idx)
if reset {
tb.Logf("found winner %d %s, idx %d", i, stage, idx)
winner = i
// stage = stage1
break
}
}
}
if !reset {
result |= 1 << (bitlength - 1 - idx)
junction = idx
stage = stage2
for i := range n {
lost[i] = lost[i] || lost_round[i]
}
}
}
tb.Logf("lost: %t, result: %08b", lost, result)
}
if result != max2 {
tb.Fatalf("wrong result: %0[1]*[2]b, exp. max2: %0[1]*[3]b, max: %0[1]*[4]b\nvals: %0[1]*[5]b", bitlength, result, max2, max, vals)
}
if max_idx != winner {
tb.Fatalf("wrong winner, max_idx: %d vs winner: %d val %08b\nvals: %08b", max_idx, winner, max2, vals)
}
}
func TestAuction4on6bit(t *testing.T) { runSeal(4, 6, t) }
// func TestAuction100on24bit(t *testing.T) { runSeal(100, 24, t) }
func TestVickrey4on6bit(t *testing.T) { runVickrey(4, 6, t) }
func TestVickrey100on16bit(t *testing.T) { runVickrey(100, 16, t) }
func BenchmarkVickrey100on24bit(b *testing.B) {
for range b.N {
runVickrey(100, 24, b)
}
}
|
