neo-go/pkg/core/native/crypto.go
2023-04-05 15:37:50 +03:00

478 lines
14 KiB
Go

package native
import (
"crypto/elliptic"
"encoding/binary"
"errors"
"fmt"
"math/big"
bls12381 "github.com/consensys/gnark-crypto/ecc/bls12-381"
"github.com/consensys/gnark-crypto/ecc/bls12-381/fr"
"github.com/decred/dcrd/dcrec/secp256k1/v4"
"github.com/nspcc-dev/neo-go/pkg/core/interop"
"github.com/nspcc-dev/neo-go/pkg/core/native/nativenames"
"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
"github.com/twmb/murmur3"
)
// Crypto represents CryptoLib contract.
type Crypto struct {
interop.ContractMD
}
// NamedCurve identifies named elliptic curves.
type NamedCurve byte
// Various named elliptic curves.
const (
Secp256k1 NamedCurve = 22
Secp256r1 NamedCurve = 23
)
const cryptoContractID = -3
func newCrypto() *Crypto {
c := &Crypto{ContractMD: *interop.NewContractMD(nativenames.CryptoLib, cryptoContractID)}
defer c.UpdateHash()
desc := newDescriptor("sha256", smartcontract.ByteArrayType,
manifest.NewParameter("data", smartcontract.ByteArrayType))
md := newMethodAndPrice(c.sha256, 1<<15, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("ripemd160", smartcontract.ByteArrayType,
manifest.NewParameter("data", smartcontract.ByteArrayType))
md = newMethodAndPrice(c.ripemd160, 1<<15, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("murmur32", smartcontract.ByteArrayType,
manifest.NewParameter("data", smartcontract.ByteArrayType),
manifest.NewParameter("seed", smartcontract.IntegerType))
md = newMethodAndPrice(c.murmur32, 1<<13, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("verifyWithECDsa", smartcontract.BoolType,
manifest.NewParameter("message", smartcontract.ByteArrayType),
manifest.NewParameter("pubkey", smartcontract.ByteArrayType),
manifest.NewParameter("signature", smartcontract.ByteArrayType),
manifest.NewParameter("curve", smartcontract.IntegerType))
md = newMethodAndPrice(c.verifyWithECDsa, 1<<15, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Serialize", smartcontract.ByteArrayType,
manifest.NewParameter("g", smartcontract.InteropInterfaceType))
md = newMethodAndPrice(c.bls12381Serialize, 1<<19, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Deserialize", smartcontract.InteropInterfaceType,
manifest.NewParameter("data", smartcontract.ByteArrayType))
md = newMethodAndPrice(c.bls12381Deserialize, 1<<19, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Equal", smartcontract.BoolType,
manifest.NewParameter("x", smartcontract.InteropInterfaceType),
manifest.NewParameter("y", smartcontract.InteropInterfaceType))
md = newMethodAndPrice(c.bls12381Equal, 1<<5, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Add", smartcontract.InteropInterfaceType,
manifest.NewParameter("x", smartcontract.InteropInterfaceType),
manifest.NewParameter("y", smartcontract.InteropInterfaceType))
md = newMethodAndPrice(c.bls12381Add, 1<<19, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Mul", smartcontract.InteropInterfaceType,
manifest.NewParameter("x", smartcontract.InteropInterfaceType),
manifest.NewParameter("mul", smartcontract.ByteArrayType),
manifest.NewParameter("neg", smartcontract.BoolType))
md = newMethodAndPrice(c.bls12381Mul, 1<<21, callflag.NoneFlag)
c.AddMethod(md, desc)
desc = newDescriptor("bls12381Pairing", smartcontract.InteropInterfaceType,
manifest.NewParameter("g1", smartcontract.InteropInterfaceType),
manifest.NewParameter("g2", smartcontract.InteropInterfaceType))
md = newMethodAndPrice(c.bls12381Pairing, 1<<23, callflag.NoneFlag)
c.AddMethod(md, desc)
return c
}
func (c *Crypto) sha256(_ *interop.Context, args []stackitem.Item) stackitem.Item {
bs, err := args[0].TryBytes()
if err != nil {
panic(err)
}
return stackitem.NewByteArray(hash.Sha256(bs).BytesBE())
}
func (c *Crypto) ripemd160(_ *interop.Context, args []stackitem.Item) stackitem.Item {
bs, err := args[0].TryBytes()
if err != nil {
panic(err)
}
return stackitem.NewByteArray(hash.RipeMD160(bs).BytesBE())
}
func (c *Crypto) murmur32(_ *interop.Context, args []stackitem.Item) stackitem.Item {
bs, err := args[0].TryBytes()
if err != nil {
panic(err)
}
seed := toUint32(args[1])
h := murmur3.SeedSum32(seed, bs)
result := make([]byte, 4)
binary.LittleEndian.PutUint32(result, h)
return stackitem.NewByteArray(result)
}
func (c *Crypto) verifyWithECDsa(_ *interop.Context, args []stackitem.Item) stackitem.Item {
msg, err := args[0].TryBytes()
if err != nil {
panic(fmt.Errorf("invalid message stackitem: %w", err))
}
hashToCheck := hash.Sha256(msg)
pubkey, err := args[1].TryBytes()
if err != nil {
panic(fmt.Errorf("invalid pubkey stackitem: %w", err))
}
signature, err := args[2].TryBytes()
if err != nil {
panic(fmt.Errorf("invalid signature stackitem: %w", err))
}
curve, err := curveFromStackitem(args[3])
if err != nil {
panic(fmt.Errorf("invalid curve stackitem: %w", err))
}
pkey, err := keys.NewPublicKeyFromBytes(pubkey, curve)
if err != nil {
panic(fmt.Errorf("failed to decode pubkey: %w", err))
}
res := pkey.Verify(signature, hashToCheck.BytesBE())
return stackitem.NewBool(res)
}
func curveFromStackitem(si stackitem.Item) (elliptic.Curve, error) {
curve, err := si.TryInteger()
if err != nil {
return nil, err
}
if !curve.IsInt64() {
return nil, errors.New("not an int64")
}
c := curve.Int64()
switch c {
case int64(Secp256k1):
return secp256k1.S256(), nil
case int64(Secp256r1):
return elliptic.P256(), nil
default:
return nil, errors.New("unsupported curve type")
}
}
func (c *Crypto) bls12381Serialize(_ *interop.Context, args []stackitem.Item) stackitem.Item {
val := args[0].(*stackitem.Interop).Value()
var res []byte
switch p := val.(type) {
case *bls12381.G1Affine:
compressed := p.Bytes()
res = compressed[:]
case *bls12381.G1Jac:
g1Affine := new(bls12381.G1Affine)
g1Affine.FromJacobian(p)
compressed := g1Affine.Bytes()
res = compressed[:]
case *bls12381.G2Affine:
compressed := p.Bytes()
res = compressed[:]
case *bls12381.G2Jac:
g2Affine := new(bls12381.G2Affine)
g2Affine.FromJacobian(p)
compressed := g2Affine.Bytes()
res = compressed[:]
case *bls12381.GT:
compressed := p.Bytes()
res = compressed[:]
default:
panic(errors.New("unknown bls12381 point type"))
}
return stackitem.NewByteArray(res)
}
func (c *Crypto) bls12381Deserialize(_ *interop.Context, args []stackitem.Item) stackitem.Item {
buf, err := args[0].TryBytes()
if err != nil {
panic(fmt.Errorf("invalid serialized bls12381 point: %w", err))
}
var res interface{}
switch l := len(buf); l {
case bls12381.SizeOfG1AffineCompressed:
g1Affine := new(bls12381.G1Affine)
_, err = g1Affine.SetBytes(buf)
if err != nil {
panic(fmt.Errorf("failed to decode bls12381 G1Affine point: %w", err))
}
res = g1Affine
case bls12381.SizeOfG2AffineCompressed:
g2Affine := new(bls12381.G2Affine)
_, err = g2Affine.SetBytes(buf)
if err != nil {
panic(fmt.Errorf("failed to decode bls12381 G2Affine point: %w", err))
}
res = g2Affine
case bls12381.SizeOfGT:
gt := new(bls12381.GT)
err := gt.SetBytes(buf)
if err != nil {
panic(fmt.Errorf("failed to decode GT point: %w", err))
}
res = gt
}
return stackitem.NewInterop(res)
}
func (c *Crypto) bls12381Equal(_ *interop.Context, args []stackitem.Item) stackitem.Item {
a := args[0].(*stackitem.Interop).Value()
b := args[1].(*stackitem.Interop).Value()
var res bool
switch x := a.(type) {
case *bls12381.G1Affine:
y, ok := b.(*bls12381.G1Affine)
if !ok {
panic(errors.New("y is not bls12381 G1Affine point"))
}
res = x.Equal(y)
case *bls12381.G1Jac:
y, ok := b.(*bls12381.G1Jac)
if !ok {
panic(errors.New("y is not bls12381 G1Jac point"))
}
res = x.Equal(y)
case *bls12381.G2Affine:
y, ok := b.(*bls12381.G2Affine)
if !ok {
panic(errors.New("y is not bls12381 G2Affine point"))
}
res = x.Equal(y)
case *bls12381.G2Jac:
y, ok := b.(*bls12381.G2Jac)
if !ok {
panic(errors.New("y is not bls12381 G2Jac point"))
}
res = x.Equal(y)
default:
panic(fmt.Errorf("unexpected x bls12381 point type: %T", x))
}
return stackitem.NewBool(res)
}
func (c *Crypto) bls12381Add(_ *interop.Context, args []stackitem.Item) stackitem.Item {
a := args[0].(*stackitem.Interop).Value()
b := args[1].(*stackitem.Interop).Value()
var res interface{}
switch x := a.(type) {
case *bls12381.G1Affine:
switch y := b.(type) {
case *bls12381.G1Affine:
xJac := new(bls12381.G1Jac)
xJac.FromAffine(x)
xJac.AddMixed(y)
res = xJac
case *bls12381.G1Jac:
yJac := new(bls12381.G1Jac)
yJac.Set(y)
yJac.AddMixed(x)
res = yJac
default:
panic("inconsistent point types")
}
case *bls12381.G1Jac:
resJac := new(bls12381.G1Jac)
resJac.Set(x)
switch y := b.(type) {
case *bls12381.G1Affine:
resJac.AddMixed(y)
case *bls12381.G1Jac:
resJac.AddAssign(y)
default:
panic("inconsistent")
}
res = resJac
case *bls12381.G2Affine:
switch y := b.(type) {
case *bls12381.G2Affine:
xJac := new(bls12381.G2Jac)
xJac.FromAffine(x)
xJac.AddMixed(y)
res = xJac
case *bls12381.G2Jac:
yJac := new(bls12381.G2Jac)
yJac.Set(y)
yJac.AddMixed(x)
res = yJac
default:
panic("inconsistent")
}
case *bls12381.G2Jac:
resJac := new(bls12381.G2Jac)
resJac.Set(x)
switch y := b.(type) {
case *bls12381.G2Affine:
resJac.AddMixed(y)
case *bls12381.G2Jac:
resJac.AddAssign(y)
default:
panic("invalid")
}
res = resJac
case *bls12381.GT:
resGT := new(bls12381.GT)
resGT.Set(x)
switch y := b.(type) {
case *bls12381.GT:
// It's multiplication, see https://github.com/neo-project/Neo.Cryptography.BLS12_381/issues/4.
resGT.Mul(x, y)
default:
panic("invalid")
}
res = resGT
default:
panic(fmt.Errorf("unexpected bls12381 point type: %T", x))
}
return stackitem.NewInterop(res)
}
func scalarFromBytes(bytes []byte, neg bool) (*fr.Element, error) {
alpha := new(fr.Element)
if len(bytes) != fr.Bytes {
return nil, fmt.Errorf("invalid multiplier: 32-bytes scalar is expected, got %d", len(bytes))
}
// The input bytes are in the LE form, so we can't use fr.Element.SetBytesCanonical as far
// as it accepts BE.
v, err := fr.LittleEndian.Element((*[fr.Bytes]byte)(bytes))
if err != nil {
return nil, fmt.Errorf("invalid multiplier: failed to decode scalar: %w", err)
}
*alpha = v
if neg {
alpha.Neg(alpha)
}
return alpha, nil
}
func (c *Crypto) bls12381Mul(_ *interop.Context, args []stackitem.Item) stackitem.Item {
a := args[0].(*stackitem.Interop).Value()
mulBytes, err := args[1].TryBytes()
if err != nil {
panic(fmt.Errorf("invalid multiplier: %w", err))
}
neg, err := args[2].TryBool()
if err != nil {
panic(fmt.Errorf("invalid negative argument: %w", err))
}
alpha, err := scalarFromBytes(mulBytes, neg)
if err != nil {
panic(err)
}
alphaBi := new(big.Int)
alpha.BigInt(alphaBi)
var res interface{}
switch x := a.(type) {
case *bls12381.G1Affine:
// The result is in Jacobian form in the reference implementation.
g1Jac := new(bls12381.G1Jac)
g1Jac.FromAffine(x)
g1Jac.ScalarMultiplication(g1Jac, alphaBi)
res = g1Jac
case *bls12381.G1Jac:
g1Jac := new(bls12381.G1Jac)
g1Jac.ScalarMultiplication(x, alphaBi)
res = g1Jac
case *bls12381.G2Affine:
// The result is in Jacobian form in the reference implementation.
g2Jac := new(bls12381.G2Jac)
g2Jac.FromAffine(x)
g2Jac.ScalarMultiplication(g2Jac, alphaBi)
res = g2Jac
case *bls12381.G2Jac:
g2Jac := new(bls12381.G2Jac)
g2Jac.ScalarMultiplication(x, alphaBi)
res = g2Jac
case *bls12381.GT:
gt := new(bls12381.GT)
// C# implementation differs a bit from go's. They use double-and-add algorithm, see
// https://github.com/neo-project/Neo.Cryptography.BLS12_381/blob/844bc3a4f7d8ba2c545ace90ca124f8ada4c8d29/src/Neo.Cryptography.BLS12_381/Gt.cs#L102
// and https://en.wikipedia.org/wiki/Elliptic_curve_point_multiplication#Double-and-add,
// Pay attention that C#'s Gt.Double() squares (not doubles!) the initial GT point.
// Thus.C#'s scalar multiplication operation over Gt and Scalar is effectively an exponent.
// Go's exponent algorithm differs a bit from the C#'s double-and-add in that go's one
// uses 2-bits windowed method for multiplication. However, the resulting GT point is
// absolutely the same between two implementations.
gt.Exp(*x, alphaBi)
res = gt
default:
panic(fmt.Errorf("unexpected bls12381 point type: %T", x))
}
return stackitem.NewInterop(res)
}
func (c *Crypto) bls12381Pairing(_ *interop.Context, args []stackitem.Item) stackitem.Item {
a := args[0].(*stackitem.Interop).Value()
b := args[1].(*stackitem.Interop).Value()
var (
x *bls12381.G1Affine
y *bls12381.G2Affine
)
switch p := a.(type) {
case *bls12381.G1Affine:
x = p
case *bls12381.G1Jac:
x = new(bls12381.G1Affine)
x.FromJacobian(p)
default:
panic(fmt.Errorf("unexpected bls12381 point type (g1): %T", x))
}
switch p := b.(type) {
case *bls12381.G2Affine:
y = p
case *bls12381.G2Jac:
y = new(bls12381.G2Affine)
y.FromJacobian(p)
default:
panic(fmt.Errorf("unexpected bls12381 point type (g2): %T", x))
}
gt, err := bls12381.Pair([]bls12381.G1Affine{*x}, []bls12381.G2Affine{*y})
if err != nil {
panic(fmt.Errorf("failed to perform pairing operation"))
}
return stackitem.NewInterop(interface{}(&gt))
}
// Metadata implements the Contract interface.
func (c *Crypto) Metadata() *interop.ContractMD {
return &c.ContractMD
}
// Initialize implements the Contract interface.
func (c *Crypto) Initialize(ic *interop.Context) error {
return nil
}
// OnPersist implements the Contract interface.
func (c *Crypto) OnPersist(ic *interop.Context) error {
return nil
}
// PostPersist implements the Contract interface.
func (c *Crypto) PostPersist(ic *interop.Context) error {
return nil
}