jwt: Add JWT support for minio server.

Please read JWT.md before using this feature.

api-auth-utils.go

@@ -0,0 +1,78 @@
+/*
+ * Minio Cloud Storage, (C) 2015 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 main
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+	"regexp"
+
+	"github.com/minio/minio-xl/pkg/probe"
+)
+
+const (
+	minioAccessID = 20
+	minioSecretID = 40
+)
+
+// isValidAccessKey - validate access key
+func isValidAccessKey(accessKeyID string) bool {
+	if accessKeyID == "" {
+		return true
+	}
+	regex := regexp.MustCompile("^[A-Z0-9\\-\\.\\_\\~]{20}$")
+	return regex.MatchString(accessKeyID)
+}
+
+// generateAccessKeyID - generate random alpha numeric value using only uppercase characters
+// takes input as size in integer
+func generateAccessKeyID() ([]byte, *probe.Error) {
+	alpha := make([]byte, minioAccessID)
+	_, err := rand.Read(alpha)
+	if err != nil {
+		return nil, probe.NewError(err)
+	}
+	for i := 0; i < minioAccessID; i++ {
+		alpha[i] = alphaNumericTable[alpha[i]%byte(len(alphaNumericTable))]
+	}
+	return alpha, nil
+}
+
+// generateSecretAccessKey - generate random base64 numeric value from a random seed.
+func generateSecretAccessKey() ([]byte, *probe.Error) {
+	rb := make([]byte, minioSecretID)
+	_, err := rand.Read(rb)
+	if err != nil {
+		return nil, probe.NewError(err)
+	}
+	return []byte(base64.StdEncoding.EncodeToString(rb))[:minioSecretID], nil
+}
+
+// mustGenerateAccessKeyID - must generate random alpha numeric value using only uppercase characters
+// takes input as size in integer
+func mustGenerateAccessKeyID() []byte {
+	alpha, err := generateAccessKeyID()
+	fatalIf(err.Trace(), "Unable to generate accessKeyID.", nil)
+	return alpha
+}
+
+// mustGenerateSecretAccessKey - generate random base64 numeric value from a random seed.
+func mustGenerateSecretAccessKey() []byte {
+	secretKey, err := generateSecretAccessKey()
+	fatalIf(err.Trace(), "Unable to generate secretAccessKey.", nil)
+	return secretKey
+}