Add SHA-3 support (#9308)

cmd/config/identity/openid/rsa-sha3.go

@@ -0,0 +1,51 @@
+/*
+ * MinIO Cloud Storage, (C) 2020 MinIO, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package openid
+
+import (
+	"crypto"
+	"github.com/dgrijalva/jwt-go"
+	// Needed for SHA3 to work - See: https://golang.org/src/crypto/crypto.go?s=1034:1288
+	_ "golang.org/x/crypto/sha3"
+)
+
+// Specific instances for RS256 and company
+var (
+	SigningMethodRS3256 *jwt.SigningMethodRSA
+	SigningMethodRS3384 *jwt.SigningMethodRSA
+	SigningMethodRS3512 *jwt.SigningMethodRSA
+)
+
+func init() {
+	// RS3256
+	SigningMethodRS3256 = &jwt.SigningMethodRSA{Name: "RS3256", Hash: crypto.SHA3_256}
+	jwt.RegisterSigningMethod(SigningMethodRS3256.Alg(), func() jwt.SigningMethod {
+		return SigningMethodRS3256
+	})
+
+	// RS3384
+	SigningMethodRS3384 = &jwt.SigningMethodRSA{Name: "RS3384", Hash: crypto.SHA3_384}
+	jwt.RegisterSigningMethod(SigningMethodRS3384.Alg(), func() jwt.SigningMethod {
+		return SigningMethodRS3384
+	})
+
+	// RS3512
+	SigningMethodRS3512 = &jwt.SigningMethodRSA{Name: "RS3512", Hash: crypto.SHA3_512}
+	jwt.RegisterSigningMethod(SigningMethodRS3512.Alg(), func() jwt.SigningMethod {
+		return SigningMethodRS3512
+	})
+}