server: Move all the top level files into cmd folder. (#2490)

This change brings a change which was done for the 'mc'
package to allow for clean repo and have a cleaner
github drop in experience.

cmd/signature-jwt.go

@@ -0,0 +1,101 @@
+/*
+ * Minio Cloud Storage, (C) 2016 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 cmd
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	jwtgo "github.com/dgrijalva/jwt-go"
+	"golang.org/x/crypto/bcrypt"
+)
+
+const jwtAlgorithm = "Bearer"
+
+// JWT - jwt auth backend
+type JWT struct {
+	credential
+}
+
+// Default - each token expires in 10hrs.
+const (
+	tokenExpires time.Duration = 10
+)
+
+// newJWT - returns new JWT object.
+func newJWT() (*JWT, error) {
+	if serverConfig == nil {
+		return nil, fmt.Errorf("server not initialzed")
+	}
+
+	// Save access, secret keys.
+	cred := serverConfig.GetCredential()
+	if !isValidAccessKey.MatchString(cred.AccessKeyID) {
+		return nil, fmt.Errorf("Invalid access key")
+	}
+	if !isValidSecretKey.MatchString(cred.SecretAccessKey) {
+		return nil, fmt.Errorf("Invalid secret key")
+	}
+
+	return &JWT{cred}, nil
+}
+
+// GenerateToken - generates a new Json Web Token based on the incoming access key.
+func (jwt *JWT) GenerateToken(accessKey string) (string, error) {
+	// Trim spaces.
+	accessKey = strings.TrimSpace(accessKey)
+
+	if !isValidAccessKey.MatchString(accessKey) {
+		return "", fmt.Errorf("Invalid access key")
+	}
+
+	tUTCNow := time.Now().UTC()
+	token := jwtgo.NewWithClaims(jwtgo.SigningMethodHS512, jwtgo.MapClaims{
+		// Token expires in 10hrs.
+		"exp": tUTCNow.Add(time.Hour * tokenExpires).Unix(),
+		"iat": tUTCNow.Unix(),
+		"sub": accessKey,
+	})
+	return token.SignedString([]byte(jwt.SecretAccessKey))
+}
+
+// Authenticate - authenticates incoming access key and secret key.
+func (jwt *JWT) Authenticate(accessKey, secretKey string) error {
+	// Trim spaces.
+	accessKey = strings.TrimSpace(accessKey)
+
+	if !isValidAccessKey.MatchString(accessKey) {
+		return fmt.Errorf("Invalid access key")
+	}
+	if !isValidSecretKey.MatchString(secretKey) {
+		return fmt.Errorf("Invalid secret key")
+	}
+
+	if accessKey != jwt.AccessKeyID {
+		return fmt.Errorf("Access key does not match")
+	}
+
+	hashedSecretKey, _ := bcrypt.GenerateFromPassword([]byte(jwt.SecretAccessKey), bcrypt.DefaultCost)
+
+	if bcrypt.CompareHashAndPassword(hashedSecretKey, []byte(secretKey)) != nil {
+		return fmt.Errorf("Authentication failed")
+	}
+
+	// Success.
+	return nil
+}