accounts, core, crypto, internal: use normalised V during signature handling (#3455)

To address increasing complexity in code that handles signatures, this PR
discards all notion of "different" signature types at the library level. Both
the crypto and accounts package is reduced to only be able to produce plain
canonical secp256k1 signatures. This makes the crpyto APIs much cleaner,
simpler and harder to abuse.

1 files changed, 24 insertions, 50 deletions

diff --git a/crypto/crypto_test.go b/crypto/crypto_test.go
index 80c9a9aae..86a582306 100644
--- a/crypto/crypto_test.go
+++ b/crypto/crypto_test.go
@@ -80,22 +80,15 @@ func Test0Key(t *testing.T) {
 	}
 }
 
-func testSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing.T) {
+func TestSign(t *testing.T) {
 	key, _ := HexToECDSA(testPrivHex)
 	addr := common.HexToAddress(testAddrHex)
 
 	msg := Keccak256([]byte("foo"))
-	sig, err := signfn(msg, key)
+	sig, err := Sign(msg, key)
 	if err != nil {
 		t.Errorf("Sign error: %s", err)
 	}
-
-	// signfn can return a recover id of either [0,1] or [27,28].
-	// In the latter case its an Ethereum signature, adjust recover id.
-	if sig[64] == 27 || sig[64] == 28 {
-		sig[64] -= 27
-	}
-
 	recoveredPub, err := Ecrecover(msg, sig)
 	if err != nil {
 		t.Errorf("ECRecover error: %s", err)
@@ -117,34 +110,15 @@ func testSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing
 	}
 }
 
-func TestSign(t *testing.T) {
-	testSign(Sign, t)
-}
-
-func TestSignEthereum(t *testing.T) {
-	testSign(SignEthereum, t)
-}
-
-func testInvalidSign(signfn func([]byte, *ecdsa.PrivateKey) ([]byte, error), t *testing.T) {
-	_, err := signfn(make([]byte, 1), nil)
-	if err == nil {
+func TestInvalidSign(t *testing.T) {
+	if _, err := Sign(make([]byte, 1), nil); err == nil {
 		t.Errorf("expected sign with hash 1 byte to error")
 	}
-
-	_, err = signfn(make([]byte, 33), nil)
-	if err == nil {
+	if _, err := Sign(make([]byte, 33), nil); err == nil {
 		t.Errorf("expected sign with hash 33 byte to error")
 	}
 }
 
-func TestInvalidSign(t *testing.T) {
-	testInvalidSign(Sign, t)
-}
-
-func TestInvalidSignEthereum(t *testing.T) {
-	testInvalidSign(SignEthereum, t)
-}
-
 func TestNewContractAddress(t *testing.T) {
 	key, _ := HexToECDSA(testPrivHex)
 	addr := common.HexToAddress(testAddrHex)
@@ -207,38 +181,38 @@ func TestValidateSignatureValues(t *testing.T) {
 	secp256k1nMinus1 := new(big.Int).Sub(secp256k1.N, common.Big1)
 
 	// correct v,r,s
-	check(true, 27, one, one)
-	check(true, 28, one, one)
+	check(true, 0, one, one)
+	check(true, 1, one, one)
 	// incorrect v, correct r,s,
-	check(false, 30, one, one)
-	check(false, 26, one, one)
+	check(false, 2, one, one)
+	check(false, 3, one, one)
 
 	// incorrect v, combinations of incorrect/correct r,s at lower limit
+	check(false, 2, zero, zero)
+	check(false, 2, zero, one)
+	check(false, 2, one, zero)
+	check(false, 2, one, one)
+
+	// correct v for any combination of incorrect r,s
 	check(false, 0, zero, zero)
 	check(false, 0, zero, one)
 	check(false, 0, one, zero)
-	check(false, 0, one, one)
-
-	// correct v for any combination of incorrect r,s
-	check(false, 27, zero, zero)
-	check(false, 27, zero, one)
-	check(false, 27, one, zero)
 
-	check(false, 28, zero, zero)
-	check(false, 28, zero, one)
-	check(false, 28, one, zero)
+	check(false, 1, zero, zero)
+	check(false, 1, zero, one)
+	check(false, 1, one, zero)
 
 	// correct sig with max r,s
-	check(true, 27, secp256k1nMinus1, secp256k1nMinus1)
+	check(true, 0, secp256k1nMinus1, secp256k1nMinus1)
 	// correct v, combinations of incorrect r,s at upper limit
-	check(false, 27, secp256k1.N, secp256k1nMinus1)
-	check(false, 27, secp256k1nMinus1, secp256k1.N)
-	check(false, 27, secp256k1.N, secp256k1.N)
+	check(false, 0, secp256k1.N, secp256k1nMinus1)
+	check(false, 0, secp256k1nMinus1, secp256k1.N)
+	check(false, 0, secp256k1.N, secp256k1.N)
 
 	// current callers ensures r,s cannot be negative, but let's test for that too
 	// as crypto package could be used stand-alone
-	check(false, 27, minusOne, one)
-	check(false, 27, one, minusOne)
+	check(false, 0, minusOne, one)
+	check(false, 0, one, minusOne)
 }
 
 func checkhash(t *testing.T, name string, f func([]byte) []byte, msg, exp []byte) {