diff options
Diffstat (limited to 'core/vm/contracts.go')
| -rw-r--r-- | core/vm/contracts.go | 487 |
1 files changed, 475 insertions, 12 deletions
diff --git a/core/vm/contracts.go b/core/vm/contracts.go index 54eab4e..9827bac 100644 --- a/core/vm/contracts.go +++ b/core/vm/contracts.go @@ -23,11 +23,14 @@ import ( "math/big" "github.com/ava-labs/coreth/params" - "github.com/ava-labs/go-ethereum/common" - "github.com/ava-labs/go-ethereum/common/math" - "github.com/ava-labs/go-ethereum/crypto" - "github.com/ava-labs/go-ethereum/crypto/blake2b" - "github.com/ava-labs/go-ethereum/crypto/bn256" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/common/math" + "github.com/ethereum/go-ethereum/crypto" + "github.com/ethereum/go-ethereum/crypto/blake2b" + "github.com/ethereum/go-ethereum/crypto/bls12381" + "github.com/ethereum/go-ethereum/crypto/bn256" + + //lint:ignore SA1019 Needed for precompile "golang.org/x/crypto/ripemd160" ) @@ -75,13 +78,42 @@ var PrecompiledContractsIstanbul = map[common.Address]PrecompiledContract{ common.BytesToAddress([]byte{9}): &blake2F{}, } +// PrecompiledContractsYoloV1 contains the default set of pre-compiled Ethereum +// contracts used in the Yolo v1 test release. +var PrecompiledContractsYoloV1 = map[common.Address]PrecompiledContract{ + common.BytesToAddress([]byte{1}): &ecrecover{}, + common.BytesToAddress([]byte{2}): &sha256hash{}, + common.BytesToAddress([]byte{3}): &ripemd160hash{}, + common.BytesToAddress([]byte{4}): &dataCopy{}, + common.BytesToAddress([]byte{5}): &bigModExp{}, + common.BytesToAddress([]byte{6}): &bn256AddIstanbul{}, + common.BytesToAddress([]byte{7}): &bn256ScalarMulIstanbul{}, + common.BytesToAddress([]byte{8}): &bn256PairingIstanbul{}, + common.BytesToAddress([]byte{9}): &blake2F{}, + common.BytesToAddress([]byte{10}): &bls12381G1Add{}, + common.BytesToAddress([]byte{11}): &bls12381G1Mul{}, + common.BytesToAddress([]byte{12}): &bls12381G1MultiExp{}, + common.BytesToAddress([]byte{13}): &bls12381G2Add{}, + common.BytesToAddress([]byte{14}): &bls12381G2Mul{}, + common.BytesToAddress([]byte{15}): &bls12381G2MultiExp{}, + common.BytesToAddress([]byte{16}): &bls12381Pairing{}, + common.BytesToAddress([]byte{17}): &bls12381MapG1{}, + common.BytesToAddress([]byte{18}): &bls12381MapG2{}, +} + // RunPrecompiledContract runs and evaluates the output of a precompiled contract. -func RunPrecompiledContract(p PrecompiledContract, input []byte, contract *Contract) (ret []byte, err error) { - gas := p.RequiredGas(input) - if contract.UseGas(gas) { - return p.Run(input) +// It returns +// - the returned bytes, +// - the _remaining_ gas, +// - any error that occurred +func RunPrecompiledContract(p PrecompiledContract, input []byte, suppliedGas uint64) (ret []byte, remainingGas uint64, err error) { + gasCost := p.RequiredGas(input) + if suppliedGas < gasCost { + return nil, 0, ErrOutOfGas } - return nil, ErrOutOfGas + suppliedGas -= gasCost + output, err := p.Run(input) + return output, suppliedGas, err } // ECRECOVER implemented as a native contract. @@ -106,8 +138,13 @@ func (c *ecrecover) Run(input []byte) ([]byte, error) { if !allZero(input[32:63]) || !crypto.ValidateSignatureValues(v, r, s, false) { return nil, nil } + // We must make sure not to modify the 'input', so placing the 'v' along with + // the signature needs to be done on a new allocation + sig := make([]byte, 65) + copy(sig, input[64:128]) + sig[64] = v // v needs to be at the end for libsecp256k1 - pubKey, err := crypto.Ecrecover(input[:32], append(input[64:128], v)) + pubKey, err := crypto.Ecrecover(input[:32], sig) // make sure the public key is a valid one if err != nil { return nil, nil @@ -166,6 +203,7 @@ func (c *dataCopy) Run(in []byte) ([]byte, error) { type bigModExp struct{} var ( + big0 = big.NewInt(0) big1 = big.NewInt(1) big4 = big.NewInt(4) big8 = big.NewInt(8) @@ -458,7 +496,7 @@ var ( ) func (c *blake2F) Run(input []byte) ([]byte, error) { - // Make sure the input is valid (correct lenth and final flag) + // Make sure the input is valid (correct length and final flag) if len(input) != blake2FInputLength { return nil, errBlake2FInvalidInputLength } @@ -495,3 +533,428 @@ func (c *blake2F) Run(input []byte) ([]byte, error) { } return output, nil } + +var ( + errBLS12381InvalidInputLength = errors.New("invalid input length") + errBLS12381InvalidFieldElementTopBytes = errors.New("invalid field element top bytes") + errBLS12381G1PointSubgroup = errors.New("g1 point is not on correct subgroup") + errBLS12381G2PointSubgroup = errors.New("g2 point is not on correct subgroup") +) + +// bls12381G1Add implements EIP-2537 G1Add precompile. +type bls12381G1Add struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G1Add) RequiredGas(input []byte) uint64 { + return params.Bls12381G1AddGas +} + +func (c *bls12381G1Add) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G1Add precompile. + // > G1 addition call expects `256` bytes as an input that is interpreted as byte concatenation of two G1 points (`128` bytes each). + // > Output is an encoding of addition operation result - single G1 point (`128` bytes). + if len(input) != 256 { + return nil, errBLS12381InvalidInputLength + } + var err error + var p0, p1 *bls12381.PointG1 + + // Initialize G1 + g := bls12381.NewG1() + + // Decode G1 point p_0 + if p0, err = g.DecodePoint(input[:128]); err != nil { + return nil, err + } + // Decode G1 point p_1 + if p1, err = g.DecodePoint(input[128:]); err != nil { + return nil, err + } + + // Compute r = p_0 + p_1 + r := g.New() + g.Add(r, p0, p1) + + // Encode the G1 point result into 128 bytes + return g.EncodePoint(r), nil +} + +// bls12381G1Mul implements EIP-2537 G1Mul precompile. +type bls12381G1Mul struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G1Mul) RequiredGas(input []byte) uint64 { + return params.Bls12381G1MulGas +} + +func (c *bls12381G1Mul) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G1Mul precompile. + // > G1 multiplication call expects `160` bytes as an input that is interpreted as byte concatenation of encoding of G1 point (`128` bytes) and encoding of a scalar value (`32` bytes). + // > Output is an encoding of multiplication operation result - single G1 point (`128` bytes). + if len(input) != 160 { + return nil, errBLS12381InvalidInputLength + } + var err error + var p0 *bls12381.PointG1 + + // Initialize G1 + g := bls12381.NewG1() + + // Decode G1 point + if p0, err = g.DecodePoint(input[:128]); err != nil { + return nil, err + } + // Decode scalar value + e := new(big.Int).SetBytes(input[128:]) + + // Compute r = e * p_0 + r := g.New() + g.MulScalar(r, p0, e) + + // Encode the G1 point into 128 bytes + return g.EncodePoint(r), nil +} + +// bls12381G1MultiExp implements EIP-2537 G1MultiExp precompile. +type bls12381G1MultiExp struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G1MultiExp) RequiredGas(input []byte) uint64 { + // Calculate G1 point, scalar value pair length + k := len(input) / 160 + if k == 0 { + // Return 0 gas for small input length + return 0 + } + // Lookup discount value for G1 point, scalar value pair length + var discount uint64 + if dLen := len(params.Bls12381MultiExpDiscountTable); k < dLen { + discount = params.Bls12381MultiExpDiscountTable[k-1] + } else { + discount = params.Bls12381MultiExpDiscountTable[dLen-1] + } + // Calculate gas and return the result + return (uint64(k) * params.Bls12381G1MulGas * discount) / 1000 +} + +func (c *bls12381G1MultiExp) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G1MultiExp precompile. + // G1 multiplication call expects `160*k` bytes as an input that is interpreted as byte concatenation of `k` slices each of them being a byte concatenation of encoding of G1 point (`128` bytes) and encoding of a scalar value (`32` bytes). + // Output is an encoding of multiexponentiation operation result - single G1 point (`128` bytes). + k := len(input) / 160 + if len(input) == 0 || len(input)%160 != 0 { + return nil, errBLS12381InvalidInputLength + } + var err error + points := make([]*bls12381.PointG1, k) + scalars := make([]*big.Int, k) + + // Initialize G1 + g := bls12381.NewG1() + + // Decode point scalar pairs + for i := 0; i < k; i++ { + off := 160 * i + t0, t1, t2 := off, off+128, off+160 + // Decode G1 point + if points[i], err = g.DecodePoint(input[t0:t1]); err != nil { + return nil, err + } + // Decode scalar value + scalars[i] = new(big.Int).SetBytes(input[t1:t2]) + } + + // Compute r = e_0 * p_0 + e_1 * p_1 + ... + e_(k-1) * p_(k-1) + r := g.New() + g.MultiExp(r, points, scalars) + + // Encode the G1 point to 128 bytes + return g.EncodePoint(r), nil +} + +// bls12381G2Add implements EIP-2537 G2Add precompile. +type bls12381G2Add struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G2Add) RequiredGas(input []byte) uint64 { + return params.Bls12381G2AddGas +} + +func (c *bls12381G2Add) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G2Add precompile. + // > G2 addition call expects `512` bytes as an input that is interpreted as byte concatenation of two G2 points (`256` bytes each). + // > Output is an encoding of addition operation result - single G2 point (`256` bytes). + if len(input) != 512 { + return nil, errBLS12381InvalidInputLength + } + var err error + var p0, p1 *bls12381.PointG2 + + // Initialize G2 + g := bls12381.NewG2() + r := g.New() + + // Decode G2 point p_0 + if p0, err = g.DecodePoint(input[:256]); err != nil { + return nil, err + } + // Decode G2 point p_1 + if p1, err = g.DecodePoint(input[256:]); err != nil { + return nil, err + } + + // Compute r = p_0 + p_1 + g.Add(r, p0, p1) + + // Encode the G2 point into 256 bytes + return g.EncodePoint(r), nil +} + +// bls12381G2Mul implements EIP-2537 G2Mul precompile. +type bls12381G2Mul struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G2Mul) RequiredGas(input []byte) uint64 { + return params.Bls12381G2MulGas +} + +func (c *bls12381G2Mul) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G2MUL precompile logic. + // > G2 multiplication call expects `288` bytes as an input that is interpreted as byte concatenation of encoding of G2 point (`256` bytes) and encoding of a scalar value (`32` bytes). + // > Output is an encoding of multiplication operation result - single G2 point (`256` bytes). + if len(input) != 288 { + return nil, errBLS12381InvalidInputLength + } + var err error + var p0 *bls12381.PointG2 + + // Initialize G2 + g := bls12381.NewG2() + + // Decode G2 point + if p0, err = g.DecodePoint(input[:256]); err != nil { + return nil, err + } + // Decode scalar value + e := new(big.Int).SetBytes(input[256:]) + + // Compute r = e * p_0 + r := g.New() + g.MulScalar(r, p0, e) + + // Encode the G2 point into 256 bytes + return g.EncodePoint(r), nil +} + +// bls12381G2MultiExp implements EIP-2537 G2MultiExp precompile. +type bls12381G2MultiExp struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381G2MultiExp) RequiredGas(input []byte) uint64 { + // Calculate G2 point, scalar value pair length + k := len(input) / 288 + if k == 0 { + // Return 0 gas for small input length + return 0 + } + // Lookup discount value for G2 point, scalar value pair length + var discount uint64 + if dLen := len(params.Bls12381MultiExpDiscountTable); k < dLen { + discount = params.Bls12381MultiExpDiscountTable[k-1] + } else { + discount = params.Bls12381MultiExpDiscountTable[dLen-1] + } + // Calculate gas and return the result + return (uint64(k) * params.Bls12381G2MulGas * discount) / 1000 +} + +func (c *bls12381G2MultiExp) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 G2MultiExp precompile logic + // > G2 multiplication call expects `288*k` bytes as an input that is interpreted as byte concatenation of `k` slices each of them being a byte concatenation of encoding of G2 point (`256` bytes) and encoding of a scalar value (`32` bytes). + // > Output is an encoding of multiexponentiation operation result - single G2 point (`256` bytes). + k := len(input) / 288 + if len(input) == 0 || len(input)%288 != 0 { + return nil, errBLS12381InvalidInputLength + } + var err error + points := make([]*bls12381.PointG2, k) + scalars := make([]*big.Int, k) + + // Initialize G2 + g := bls12381.NewG2() + + // Decode point scalar pairs + for i := 0; i < k; i++ { + off := 288 * i + t0, t1, t2 := off, off+256, off+288 + // Decode G1 point + if points[i], err = g.DecodePoint(input[t0:t1]); err != nil { + return nil, err + } + // Decode scalar value + scalars[i] = new(big.Int).SetBytes(input[t1:t2]) + } + + // Compute r = e_0 * p_0 + e_1 * p_1 + ... + e_(k-1) * p_(k-1) + r := g.New() + g.MultiExp(r, points, scalars) + + // Encode the G2 point to 256 bytes. + return g.EncodePoint(r), nil +} + +// bls12381Pairing implements EIP-2537 Pairing precompile. +type bls12381Pairing struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381Pairing) RequiredGas(input []byte) uint64 { + return params.Bls12381PairingBaseGas + uint64(len(input)/384)*params.Bls12381PairingPerPairGas +} + +func (c *bls12381Pairing) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 Pairing precompile logic. + // > Pairing call expects `384*k` bytes as an inputs that is interpreted as byte concatenation of `k` slices. Each slice has the following structure: + // > - `128` bytes of G1 point encoding + // > - `256` bytes of G2 point encoding + // > Output is a `32` bytes where last single byte is `0x01` if pairing result is equal to multiplicative identity in a pairing target field and `0x00` otherwise + // > (which is equivalent of Big Endian encoding of Solidity values `uint256(1)` and `uin256(0)` respectively). + k := len(input) / 384 + if len(input) == 0 || len(input)%384 != 0 { + return nil, errBLS12381InvalidInputLength + } + + // Initialize BLS12-381 pairing engine + e := bls12381.NewPairingEngine() + g1, g2 := e.G1, e.G2 + + // Decode pairs + for i := 0; i < k; i++ { + off := 384 * i + t0, t1, t2 := off, off+128, off+384 + + // Decode G1 point + p1, err := g1.DecodePoint(input[t0:t1]) + if err != nil { + return nil, err + } + // Decode G2 point + p2, err := g2.DecodePoint(input[t1:t2]) + if err != nil { + return nil, err + } + + // 'point is on curve' check already done, + // Here we need to apply subgroup checks. + if !g1.InCorrectSubgroup(p1) { + return nil, errBLS12381G1PointSubgroup + } + if !g2.InCorrectSubgroup(p2) { + return nil, errBLS12381G2PointSubgroup + } + + // Update pairing engine with G1 and G2 ponits + e.AddPair(p1, p2) + } + // Prepare 32 byte output + out := make([]byte, 32) + + // Compute pairing and set the result + if e.Check() { + out[31] = 1 + } + return out, nil +} + +// decodeBLS12381FieldElement decodes BLS12-381 elliptic curve field element. +// Removes top 16 bytes of 64 byte input. +func decodeBLS12381FieldElement(in []byte) ([]byte, error) { + if len(in) != 64 { + return nil, errors.New("invalid field element length") + } + // check top bytes + for i := 0; i < 16; i++ { + if in[i] != byte(0x00) { + return nil, errBLS12381InvalidFieldElementTopBytes + } + } + out := make([]byte, 48) + copy(out[:], in[16:]) + return out, nil +} + +// bls12381MapG1 implements EIP-2537 MapG1 precompile. +type bls12381MapG1 struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381MapG1) RequiredGas(input []byte) uint64 { + return params.Bls12381MapG1Gas +} + +func (c *bls12381MapG1) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 Map_To_G1 precompile. + // > Field-to-curve call expects `64` bytes an an input that is interpreted as a an element of the base field. + // > Output of this call is `128` bytes and is G1 point following respective encoding rules. + if len(input) != 64 { + return nil, errBLS12381InvalidInputLength + } + + // Decode input field element + fe, err := decodeBLS12381FieldElement(input) + if err != nil { + return nil, err + } + + // Initialize G1 + g := bls12381.NewG1() + + // Compute mapping + r, err := g.MapToCurve(fe) + if err != nil { + return nil, err + } + + // Encode the G1 point to 128 bytes + return g.EncodePoint(r), nil +} + +// bls12381MapG2 implements EIP-2537 MapG2 precompile. +type bls12381MapG2 struct{} + +// RequiredGas returns the gas required to execute the pre-compiled contract. +func (c *bls12381MapG2) RequiredGas(input []byte) uint64 { + return params.Bls12381MapG2Gas +} + +func (c *bls12381MapG2) Run(input []byte) ([]byte, error) { + // Implements EIP-2537 Map_FP2_TO_G2 precompile logic. + // > Field-to-curve call expects `128` bytes an an input that is interpreted as a an element of the quadratic extension field. + // > Output of this call is `256` bytes and is G2 point following respective encoding rules. + if len(input) != 128 { + return nil, errBLS12381InvalidInputLength + } + + // Decode input field element + fe := make([]byte, 96) + c0, err := decodeBLS12381FieldElement(input[:64]) + if err != nil { + return nil, err + } + copy(fe[48:], c0) + c1, err := decodeBLS12381FieldElement(input[64:]) + if err != nil { + return nil, err + } + copy(fe[:48], c1) + + // Initialize G2 + g := bls12381.NewG2() + + // Compute mapping + r, err := g.MapToCurve(fe) + if err != nil { + return nil, err + } + + // Encode the G2 point to 256 bytes + return g.EncodePoint(r), nil +} |