crypto/tls: add {SignatureScheme,CurveID,ClientAuthType}.String()

Fixes #35499

Change-Id: Ieb487782f389f6d80e8f68ee980e584d906cb4da
Reviewed-on: https://go-review.googlesource.com/c/go/+/208226
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>

auth.go

@@ -106,7 +106,7 @@ func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType
 	case Ed25519:
 		sigType = signatureEd25519
 	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %#04x", signatureAlgorithm)
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
 	}
 	switch signatureAlgorithm {
 	case PKCS1WithSHA1, ECDSAWithSHA1:
@@ -120,7 +120,7 @@ func typeAndHashFromSignatureScheme(signatureAlgorithm SignatureScheme) (sigType
 	case Ed25519:
 		hash = directSigning
 	default:
-		return 0, 0, fmt.Errorf("unsupported signature algorithm: %#04x", signatureAlgorithm)
+		return 0, 0, fmt.Errorf("unsupported signature algorithm: %v", signatureAlgorithm)
 	}
 	return sigType, hash, nil
 }

auth_test.go

@@ -62,7 +62,7 @@ func TestSignatureSelection(t *testing.T) {
 			t.Errorf("test[%d]: unexpected selectSignatureScheme error: %v", testNo, err)
 		}
 		if test.expectedSigAlg != sigAlg {
-			t.Errorf("test[%d]: expected signature scheme %#x, got %#x", testNo, test.expectedSigAlg, sigAlg)
+			t.Errorf("test[%d]: expected signature scheme %v, got %v", testNo, test.expectedSigAlg, sigAlg)
 		}
 		sigType, hashFunc, err := typeAndHashFromSignatureScheme(sigAlg)
 		if err != nil {
@@ -115,7 +115,7 @@ func TestSignatureSelection(t *testing.T) {
 	for testNo, test := range badTests {
 		sigAlg, err := selectSignatureScheme(test.tlsVersion, test.cert, test.peerSigAlgs)
 		if err == nil {
-			t.Errorf("test[%d]: unexpected success, got %#x", testNo, sigAlg)
+			t.Errorf("test[%d]: unexpected success, got %v", testNo, sigAlg)
 		}
 	}
 }
@@ -129,7 +129,7 @@ func TestLegacyTypeAndHash(t *testing.T) {
 		t.Errorf("RSA: expected signature type %#x, got %#x", expectedSigType, sigType)
 	}
 	if expectedHashFunc := crypto.MD5SHA1; expectedHashFunc != hashFunc {
-		t.Errorf("RSA: expected hash %#x, got %#x", expectedHashFunc, sigType)
+		t.Errorf("RSA: expected hash %#x, got %#x", expectedHashFunc, hashFunc)
 	}
 
 	sigType, hashFunc, err = legacyTypeAndHashFromPublicKey(testECDSAPrivateKey.Public())
@@ -140,7 +140,7 @@ func TestLegacyTypeAndHash(t *testing.T) {
 		t.Errorf("ECDSA: expected signature type %#x, got %#x", expectedSigType, sigType)
 	}
 	if expectedHashFunc := crypto.SHA1; expectedHashFunc != hashFunc {
-		t.Errorf("ECDSA: expected hash %#x, got %#x", expectedHashFunc, sigType)
+		t.Errorf("ECDSA: expected hash %#x, got %#x", expectedHashFunc, hashFunc)
 	}
 
 	// Ed25519 is not supported by TLS 1.0 and 1.1.
@@ -156,13 +156,13 @@ func TestSupportedSignatureAlgorithms(t *testing.T) {
 	for _, sigAlg := range supportedSignatureAlgorithms {
 		sigType, hash, err := typeAndHashFromSignatureScheme(sigAlg)
 		if err != nil {
-			t.Errorf("%#04x: unexpected error: %v", sigAlg, err)
+			t.Errorf("%v: unexpected error: %v", sigAlg, err)
 		}
 		if sigType == 0 {
-			t.Errorf("%#04x: missing signature type", sigAlg)
+			t.Errorf("%v: missing signature type", sigAlg)
 		}
 		if hash == 0 && sigAlg != Ed25519 {
-			t.Errorf("%#04x: missing hash", sigAlg)
+			t.Errorf("%v: missing hash", sigAlg)
 		}
 	}
 }

common.go

@@ -299,6 +299,8 @@ type ClientSessionCache interface {
 	Put(sessionKey string, cs *ClientSessionState)
 }
 
+//go:generate stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go
+
 // SignatureScheme identifies a signature algorithm supported by TLS. See
 // RFC 8446, Section 4.2.3.
 type SignatureScheme uint16

common_string.go

@@ -0,0 +1,116 @@
+// Code generated by "stringer -type=SignatureScheme,CurveID,ClientAuthType -output=common_string.go"; DO NOT EDIT.
+
+package tls
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[PKCS1WithSHA256-1025]
+	_ = x[PKCS1WithSHA384-1281]
+	_ = x[PKCS1WithSHA512-1537]
+	_ = x[PSSWithSHA256-2052]
+	_ = x[PSSWithSHA384-2053]
+	_ = x[PSSWithSHA512-2054]
+	_ = x[ECDSAWithP256AndSHA256-1027]
+	_ = x[ECDSAWithP384AndSHA384-1283]
+	_ = x[ECDSAWithP521AndSHA512-1539]
+	_ = x[Ed25519-2055]
+	_ = x[PKCS1WithSHA1-513]
+	_ = x[ECDSAWithSHA1-515]
+}
+
+const (
+	_SignatureScheme_name_0 = "PKCS1WithSHA1"
+	_SignatureScheme_name_1 = "ECDSAWithSHA1"
+	_SignatureScheme_name_2 = "PKCS1WithSHA256"
+	_SignatureScheme_name_3 = "ECDSAWithP256AndSHA256"
+	_SignatureScheme_name_4 = "PKCS1WithSHA384"
+	_SignatureScheme_name_5 = "ECDSAWithP384AndSHA384"
+	_SignatureScheme_name_6 = "PKCS1WithSHA512"
+	_SignatureScheme_name_7 = "ECDSAWithP521AndSHA512"
+	_SignatureScheme_name_8 = "PSSWithSHA256PSSWithSHA384PSSWithSHA512Ed25519"
+)
+
+var (
+	_SignatureScheme_index_8 = [...]uint8{0, 13, 26, 39, 46}
+)
+
+func (i SignatureScheme) String() string {
+	switch {
+	case i == 513:
+		return _SignatureScheme_name_0
+	case i == 515:
+		return _SignatureScheme_name_1
+	case i == 1025:
+		return _SignatureScheme_name_2
+	case i == 1027:
+		return _SignatureScheme_name_3
+	case i == 1281:
+		return _SignatureScheme_name_4
+	case i == 1283:
+		return _SignatureScheme_name_5
+	case i == 1537:
+		return _SignatureScheme_name_6
+	case i == 1539:
+		return _SignatureScheme_name_7
+	case 2052 <= i && i <= 2055:
+		i -= 2052
+		return _SignatureScheme_name_8[_SignatureScheme_index_8[i]:_SignatureScheme_index_8[i+1]]
+	default:
+		return "SignatureScheme(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+}
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[CurveP256-23]
+	_ = x[CurveP384-24]
+	_ = x[CurveP521-25]
+	_ = x[X25519-29]
+}
+
+const (
+	_CurveID_name_0 = "CurveP256CurveP384CurveP521"
+	_CurveID_name_1 = "X25519"
+)
+
+var (
+	_CurveID_index_0 = [...]uint8{0, 9, 18, 27}
+)
+
+func (i CurveID) String() string {
+	switch {
+	case 23 <= i && i <= 25:
+		i -= 23
+		return _CurveID_name_0[_CurveID_index_0[i]:_CurveID_index_0[i+1]]
+	case i == 29:
+		return _CurveID_name_1
+	default:
+		return "CurveID(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+}
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[NoClientCert-0]
+	_ = x[RequestClientCert-1]
+	_ = x[RequireAnyClientCert-2]
+	_ = x[VerifyClientCertIfGiven-3]
+	_ = x[RequireAndVerifyClientCert-4]
+}
+
+const _ClientAuthType_name = "NoClientCertRequestClientCertRequireAnyClientCertVerifyClientCertIfGivenRequireAndVerifyClientCert"
+
+var _ClientAuthType_index = [...]uint8{0, 12, 29, 49, 72, 98}
+
+func (i ClientAuthType) String() string {
+	if i < 0 || i >= ClientAuthType(len(_ClientAuthType_index)-1) {
+		return "ClientAuthType(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _ClientAuthType_name[_ClientAuthType_index[i]:_ClientAuthType_index[i+1]]
+}