Restructure codebase move crypto, checksum to top-level, move `split` into donut, move crypto/keys into api/auth

pkg/server/api/auth/keys/keys.go

@@ -0,0 +1,51 @@
+/*
+ * Minimalist Object 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 keys
+
+import (
+	"crypto/rand"
+	"encoding/base64"
+)
+
+// Static alphaNumeric table used for generating unique keys
+var alphaNumericTable = []byte("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")
+
+// GenerateRandomAlphaNumeric - generate random alpha numeric value using only uppercase characters
+// takes input as size in integer
+func GenerateRandomAlphaNumeric(size int) ([]byte, error) {
+	alpha := make([]byte, size)
+	_, err := rand.Read(alpha)
+	if err != nil {
+		return nil, err
+	}
+
+	for i := 0; i < size; i++ {
+		alpha[i] = alphaNumericTable[alpha[i]%byte(len(alphaNumericTable))]
+	}
+	return alpha, nil
+}
+
+// GenerateRandomBase64 - generate random base64 numeric value from a random seed.
+func GenerateRandomBase64(size int) ([]byte, error) {
+	rb := make([]byte, size)
+	_, err := rand.Read(rb)
+	if err != nil {
+		return nil, err
+	}
+	dest := base64.StdEncoding.EncodeToString(rb)
+	return []byte(dest), nil
+}