diff options
| -rw-r--r-- | README.md | 8 | ||||
| -rw-r--r-- | avnet/avnet.go | 123 | ||||
| -rw-r--r-- | avnet/avnet_test.go | 16 | ||||
| -rw-r--r-- | go.mod | 4 | ||||
| -rw-r--r-- | go.sum | 2 | ||||
| -rw-r--r-- | go.work | 3 | ||||
| -rw-r--r-- | main.go | 35 |
7 files changed, 189 insertions, 2 deletions
@@ -4,10 +4,16 @@ This package implements the seal protocol as defined in Bag et al. - 2020 - SEAL ## Design +### AV-Net (Veto protocol) + ## TODOs - [ ] API-Design - [ ] DB-Schema - [ ] Tests -- [ ] Implementation
\ No newline at end of file +- [ ] Implementation + - [ ] Veto-Protokoll + - [ ] Commitments + - [ ] Rounds + - [ ] Variants of Rounds
\ No newline at end of file diff --git a/avnet/avnet.go b/avnet/avnet.go new file mode 100644 index 0000000..e40759f --- /dev/null +++ b/avnet/avnet.go @@ -0,0 +1,123 @@ +package avnet + +import ( + "crypto/rand" + "crypto/sha256" + "encoding/base32" + "encoding/binary" + "fmt" + "io" + + curve "filippo.io/edwards25519" +) + +var b32 = base32.StdEncoding.WithPadding(base32.NoPadding) + +// A Schnorr signature to prove knowledge of x for given g^x and i. + +type Proof struct { + PointV curve.Point + ScalarR curve.Scalar + I uint64 +} + +type Commitment struct { + PubX curve.Point + PubR curve.Point + ProofX Proof + ProofR Proof +} + +type Vote struct { + bit bool + + privX curve.Scalar + privR curve.Scalar + + Commitment +} + +func newPriv(s *curve.Scalar, random io.Reader) error { + var buf [64]byte + if random == nil { + random = rand.Reader + } + random.Read(buf[:]) + _, e := s.SetUniformBytes(buf[:]) + return e +} + +func setPub(p *curve.Scalar, P *curve.Point) *curve.Point { + return P.ScalarBaseMult(p) +} + +// Generates the proof, aka Schnorr signature, for given priv and i. +// Choosing a scalar v randomly, the signature consists of (V, r) with +// +// V := g^v, with randomly chosen v +// r := (v - x*h), with h := H(g, g^v, g^x, i), where i is given by the context. +// +// Verification of the signature is by comparing V =?= g^r * g^(x*h) +func proof(pr *Proof, x *curve.Scalar, i uint64) error { + pr.I = i + var v curve.Scalar + e := newPriv(&v, nil) + if e != nil { + return e + } + setPub(&v, &pr.PointV) + gx := curve.Point{} + setPub(x, &gx) + + // Calculate h := H(g, g^v, g^x, i) + h256 := sha256.New() + h256.Write(curve.NewGeneratorPoint().Bytes()) + h256.Write(pr.PointV.Bytes()) + h256.Write(gx.Bytes()) + e = binary.Write(h256, binary.BigEndian, i) + if e != nil { + return e + } + // h := h256.Bytes() + + // TODO: calculate r + return fmt.Errorf("proof not implemented") + +} + +func newVoteWithRand(bit bool, rand io.Reader) (vote *Vote, e error) { + vote = &Vote{ + bit: bit, + } + + e = newPriv(&vote.privX, rand) + if e != nil { + return nil, e + } + e = newPriv(&vote.privR, rand) + if e != nil { + return nil, e + } + + setPub(&vote.privX, &vote.Commitment.PubX) + setPub(&vote.privR, &vote.Commitment.PubR) + + return vote, nil +} + +func NewVote(bit bool) (vote *Vote, e error) { + return newVoteWithRand(bit, nil) +} + +func pubStr(p *curve.Point) string { + return b32.EncodeToString(p.Bytes()) +} + +func (c *Commitment) String() string { + return fmt.Sprintf(`{"PubX": "%s", "PubR": "%s"}`, pubStr(&c.PubX), pubStr(&c.PubR)) +} + +func (c *Commitment) MarshalJSON() ([]byte, error) { + s := c.String() + return []byte(s), nil +}
\ No newline at end of file diff --git a/avnet/avnet_test.go b/avnet/avnet_test.go new file mode 100644 index 0000000..8800b8b --- /dev/null +++ b/avnet/avnet_test.go @@ -0,0 +1,16 @@ +package avnet + +import ( + "testing" +) + +func TestRound(t *testing.T) { + v, e := newVoteWithRand(false, nil) + + if e != nil { + t.Fatalf("unexpected error: %v", e) + } + if v.bit { + t.Fatal("expected vote false, but got true") + } +}
\ No newline at end of file @@ -1,3 +1,5 @@ -module kesim.org/goseal +module kesim.org/seal go 1.22.0 + +require filippo.io/edwards25519 v1.1.0 // indirect @@ -0,0 +1,2 @@ +filippo.io/edwards25519 v1.1.0 h1:FNf4tywRC1HmFuKW5xopWpigGjJKiJSV0Cqo0cJWDaA= +filippo.io/edwards25519 v1.1.0/go.mod h1:BxyFTGdWcka3PhytdK4V28tE5sGfRvvvRV7EaN4VDT4= @@ -0,0 +1,3 @@ +go 1.22.0 + +use . @@ -0,0 +1,35 @@ +package seal + +import ( + "crypto" + "time" +) + +// Auction describes the asset of an auction and other +// relevant meta-data +type Auction struct { + // Start date + Start time.Time + // End date + End time.Time + // Timeout per round by which all responses must have arrived + RoundTimeout time.Duration + + // Sha512 Hash of the Asset + AssetHash string + + // Public key of the Seller + SellerPublicKey crypto.PublicKey +} + +// The SignedAuction contains an Auction and the signature, +// signed by the seller's public key off the SHA512 hash of +// the normalized JSON-object. TODO(oec): normalized? +type SignedAuction struct { + Auction + SellerSignature string +} + +// The published commiment of a participant +type Commitment struct { +} |