From 54b271a86dd748f3b0bcebeaf678dc34e0d6177a Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Thu, 22 Aug 2019 15:14:06 +0200 Subject: [PATCH] crypto: add SignatureLength constant and use it everywhere (#19996) Original change by @jpeletier --- accounts/usbwallet/ledger.go | 3 ++- consensus/clique/clique.go | 6 +++--- core/genesis.go | 3 ++- core/types/transaction_signing.go | 6 +++--- crypto/crypto.go | 9 +++++++++ crypto/signature_cgo.go | 16 ++++++++-------- crypto/signature_nocgo.go | 2 +- internal/ethapi/api.go | 10 +++++----- miner/worker_test.go | 2 +- p2p/rlpx.go | 8 ++++---- whisper/whisperv6/doc.go | 14 ++++++++------ 11 files changed, 46 insertions(+), 33 deletions(-) diff --git a/accounts/usbwallet/ledger.go b/accounts/usbwallet/ledger.go index c30903b5b7..17ca9223ff 100644 --- a/accounts/usbwallet/ledger.go +++ b/accounts/usbwallet/ledger.go @@ -32,6 +32,7 @@ import ( "github.com/ethereum/go-ethereum/common" "github.com/ethereum/go-ethereum/common/hexutil" "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/log" "github.com/ethereum/go-ethereum/rlp" ) @@ -341,7 +342,7 @@ func (w *ledgerDriver) ledgerSign(derivationPath []uint32, tx *types.Transaction op = ledgerP1ContTransactionData } // Extract the Ethereum signature and do a sanity validation - if len(reply) != 65 { + if len(reply) != crypto.SignatureLength { return common.Address{}, nil, errors.New("reply lacks signature") } signature := append(reply[1:], reply[0]) diff --git a/consensus/clique/clique.go b/consensus/clique/clique.go index 084009a066..02b6da35b2 100644 --- a/consensus/clique/clique.go +++ b/consensus/clique/clique.go @@ -55,8 +55,8 @@ const ( var ( epochLength = uint64(30000) // Default number of blocks after which to checkpoint and reset the pending votes - extraVanity = 32 // Fixed number of extra-data prefix bytes reserved for signer vanity - extraSeal = 65 // Fixed number of extra-data suffix bytes reserved for signer seal + extraVanity = 32 // Fixed number of extra-data prefix bytes reserved for signer vanity + extraSeal = crypto.SignatureLength // Fixed number of extra-data suffix bytes reserved for signer seal nonceAuthVote = hexutil.MustDecode("0xffffffffffffffff") // Magic nonce number to vote on adding a new signer nonceDropVote = hexutil.MustDecode("0x0000000000000000") // Magic nonce number to vote on removing a signer. @@ -728,7 +728,7 @@ func encodeSigHeader(w io.Writer, header *types.Header) { header.GasLimit, header.GasUsed, header.Time, - header.Extra[:len(header.Extra)-65], // Yes, this will panic if extra is too short + header.Extra[:len(header.Extra)-crypto.SignatureLength], // Yes, this will panic if extra is too short header.MixDigest, header.Nonce, }) diff --git a/core/genesis.go b/core/genesis.go index 87bab25201..5d6311b324 100644 --- a/core/genesis.go +++ b/core/genesis.go @@ -31,6 +31,7 @@ import ( "github.com/ethereum/go-ethereum/core/rawdb" "github.com/ethereum/go-ethereum/core/state" "github.com/ethereum/go-ethereum/core/types" + "github.com/ethereum/go-ethereum/crypto" "github.com/ethereum/go-ethereum/ethdb" "github.com/ethereum/go-ethereum/log" "github.com/ethereum/go-ethereum/params" @@ -377,7 +378,7 @@ func DeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis { // Assemble and return the genesis with the precompiles and faucet pre-funded return &Genesis{ Config: &config, - ExtraData: append(append(make([]byte, 32), faucet[:]...), make([]byte, 65)...), + ExtraData: append(append(make([]byte, 32), faucet[:]...), make([]byte, crypto.SignatureLength)...), GasLimit: 6283185, Difficulty: big.NewInt(1), Alloc: map[common.Address]GenesisAccount{ diff --git a/core/types/transaction_signing.go b/core/types/transaction_signing.go index 63132048ee..842fedbd03 100644 --- a/core/types/transaction_signing.go +++ b/core/types/transaction_signing.go @@ -193,8 +193,8 @@ func (s FrontierSigner) Equal(s2 Signer) bool { // SignatureValues returns signature values. This signature // needs to be in the [R || S || V] format where V is 0 or 1. func (fs FrontierSigner) SignatureValues(tx *Transaction, sig []byte) (r, s, v *big.Int, err error) { - if len(sig) != 65 { - panic(fmt.Sprintf("wrong size for signature: got %d, want 65", len(sig))) + if len(sig) != crypto.SignatureLength { + panic(fmt.Sprintf("wrong size for signature: got %d, want %d", len(sig), crypto.SignatureLength)) } r = new(big.Int).SetBytes(sig[:32]) s = new(big.Int).SetBytes(sig[32:64]) @@ -229,7 +229,7 @@ func recoverPlain(sighash common.Hash, R, S, Vb *big.Int, homestead bool) (commo } // encode the signature in uncompressed format r, s := R.Bytes(), S.Bytes() - sig := make([]byte, 65) + sig := make([]byte, crypto.SignatureLength) copy(sig[32-len(r):32], r) copy(sig[64-len(s):64], s) sig[64] = V diff --git a/crypto/crypto.go b/crypto/crypto.go index 4567fafc72..2869b4c191 100644 --- a/crypto/crypto.go +++ b/crypto/crypto.go @@ -34,6 +34,15 @@ import ( "golang.org/x/crypto/sha3" ) +//SignatureLength indicates the byte length required to carry a signature with recovery id. +const SignatureLength = 64 + 1 // 64 bytes ECDSA signature + 1 byte recovery id + +// RecoveryIDOffset points to the byte offset within the signature that contains the recovery id. +const RecoveryIDOffset = 64 + +// DigestLength sets the signature digest exact length +const DigestLength = 32 + var ( secp256k1N, _ = new(big.Int).SetString("fffffffffffffffffffffffffffffffebaaedce6af48a03bbfd25e8cd0364141", 16) secp256k1halfN = new(big.Int).Div(secp256k1N, big.NewInt(2)) diff --git a/crypto/signature_cgo.go b/crypto/signature_cgo.go index aadf028d26..1fe84509e7 100644 --- a/crypto/signature_cgo.go +++ b/crypto/signature_cgo.go @@ -47,24 +47,24 @@ func SigToPub(hash, sig []byte) (*ecdsa.PublicKey, error) { // // This function is susceptible to chosen plaintext attacks that can leak // information about the private key that is used for signing. Callers must -// be aware that the given hash cannot be chosen by an adversery. Common +// be aware that the given digest cannot be chosen by an adversery. Common // solution is to hash any input before calculating the signature. // // The produced signature is in the [R || S || V] format where V is 0 or 1. -func Sign(hash []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) { - if len(hash) != 32 { - return nil, fmt.Errorf("hash is required to be exactly 32 bytes (%d)", len(hash)) +func Sign(digestHash []byte, prv *ecdsa.PrivateKey) (sig []byte, err error) { + if len(digestHash) != DigestLength { + return nil, fmt.Errorf("hash is required to be exactly %d bytes (%d)", DigestLength, len(digestHash)) } seckey := math.PaddedBigBytes(prv.D, prv.Params().BitSize/8) defer zeroBytes(seckey) - return secp256k1.Sign(hash, seckey) + return secp256k1.Sign(digestHash, seckey) } -// VerifySignature checks that the given public key created signature over hash. +// VerifySignature checks that the given public key created signature over digest. // The public key should be in compressed (33 bytes) or uncompressed (65 bytes) format. // The signature should have the 64 byte [R || S] format. -func VerifySignature(pubkey, hash, signature []byte) bool { - return secp256k1.VerifySignature(pubkey, hash, signature) +func VerifySignature(pubkey, digestHash, signature []byte) bool { + return secp256k1.VerifySignature(pubkey, digestHash, signature) } // DecompressPubkey parses a public key in the 33-byte compressed format. diff --git a/crypto/signature_nocgo.go b/crypto/signature_nocgo.go index 90d072cda7..067d32e13c 100644 --- a/crypto/signature_nocgo.go +++ b/crypto/signature_nocgo.go @@ -41,7 +41,7 @@ func Ecrecover(hash, sig []byte) ([]byte, error) { // SigToPub returns the public key that created the given signature. func SigToPub(hash, sig []byte) (*ecdsa.PublicKey, error) { // Convert to btcec input format with 'recovery id' v at the beginning. - btcsig := make([]byte, 65) + btcsig := make([]byte, SignatureLength) btcsig[0] = sig[64] + 27 copy(btcsig[1:], sig) diff --git a/internal/ethapi/api.go b/internal/ethapi/api.go index 05204e5478..d18700e25e 100644 --- a/internal/ethapi/api.go +++ b/internal/ethapi/api.go @@ -427,7 +427,7 @@ func (s *PrivateAccountAPI) Sign(ctx context.Context, data hexutil.Bytes, addr c log.Warn("Failed data sign attempt", "address", addr, "err", err) return nil, err } - signature[64] += 27 // Transform V from 0/1 to 27/28 according to the yellow paper + signature[crypto.RecoveryIDOffset] += 27 // Transform V from 0/1 to 27/28 according to the yellow paper return signature, nil } @@ -442,13 +442,13 @@ func (s *PrivateAccountAPI) Sign(ctx context.Context, data hexutil.Bytes, addr c // // https://github.com/ethereum/go-ethereum/wiki/Management-APIs#personal_ecRecover func (s *PrivateAccountAPI) EcRecover(ctx context.Context, data, sig hexutil.Bytes) (common.Address, error) { - if len(sig) != 65 { - return common.Address{}, fmt.Errorf("signature must be 65 bytes long") + if len(sig) != crypto.SignatureLength { + return common.Address{}, fmt.Errorf("signature must be %d bytes long", crypto.SignatureLength) } - if sig[64] != 27 && sig[64] != 28 { + if sig[crypto.RecoveryIDOffset] != 27 && sig[crypto.RecoveryIDOffset] != 28 { return common.Address{}, fmt.Errorf("invalid Ethereum signature (V is not 27 or 28)") } - sig[64] -= 27 // Transform yellow paper V from 27/28 to 0/1 + sig[crypto.RecoveryIDOffset] -= 27 // Transform yellow paper V from 27/28 to 0/1 rpk, err := crypto.SigToPub(accounts.TextHash(data), sig) if err != nil { diff --git a/miner/worker_test.go b/miner/worker_test.go index 7fa9a5f984..1604e988dd 100644 --- a/miner/worker_test.go +++ b/miner/worker_test.go @@ -95,7 +95,7 @@ func newTestWorkerBackend(t *testing.T, chainConfig *params.ChainConfig, engine switch engine.(type) { case *clique.Clique: - gspec.ExtraData = make([]byte, 32+common.AddressLength+65) + gspec.ExtraData = make([]byte, 32+common.AddressLength+crypto.SignatureLength) copy(gspec.ExtraData[32:], testBankAddress[:]) case *ethash.Ethash: default: diff --git a/p2p/rlpx.go b/p2p/rlpx.go index 0636431f53..52e1eb8a4a 100644 --- a/p2p/rlpx.go +++ b/p2p/rlpx.go @@ -46,10 +46,10 @@ import ( const ( maxUint24 = ^uint32(0) >> 8 - sskLen = 16 // ecies.MaxSharedKeyLength(pubKey) / 2 - sigLen = 65 // elliptic S256 - pubLen = 64 // 512 bit pubkey in uncompressed representation without format byte - shaLen = 32 // hash length (for nonce etc) + sskLen = 16 // ecies.MaxSharedKeyLength(pubKey) / 2 + sigLen = crypto.SignatureLength // elliptic S256 + pubLen = 64 // 512 bit pubkey in uncompressed representation without format byte + shaLen = 32 // hash length (for nonce etc) authMsgLen = sigLen + shaLen + pubLen + shaLen + 1 authRespLen = pubLen + shaLen + 1 diff --git a/whisper/whisperv6/doc.go b/whisper/whisperv6/doc.go index 529bf3d2de..44c0c3271c 100644 --- a/whisper/whisperv6/doc.go +++ b/whisper/whisperv6/doc.go @@ -34,6 +34,8 @@ package whisperv6 import ( "time" + + "github.com/ethereum/go-ethereum/crypto" ) // Whisper protocol parameters @@ -54,12 +56,12 @@ const ( SizeMask = byte(3) // mask used to extract the size of payload size field from the flags signatureFlag = byte(4) - TopicLength = 4 // in bytes - signatureLength = 65 // in bytes - aesKeyLength = 32 // in bytes - aesNonceLength = 12 // in bytes; for more info please see cipher.gcmStandardNonceSize & aesgcm.NonceSize() - keyIDSize = 32 // in bytes - BloomFilterSize = 64 // in bytes + TopicLength = 4 // in bytes + signatureLength = crypto.SignatureLength // in bytes + aesKeyLength = 32 // in bytes + aesNonceLength = 12 // in bytes; for more info please see cipher.gcmStandardNonceSize & aesgcm.NonceSize() + keyIDSize = 32 // in bytes + BloomFilterSize = 64 // in bytes flagsLength = 1 EnvelopeHeaderLength = 20