Add rpc signature handler

generic-handlers.go

@@ -0,0 +1,176 @@
+/*
+ * 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 (
+	"errors"
+	"net/http"
+	"strings"
+	"time"
+
+	router "github.com/gorilla/mux"
+	"github.com/rs/cors"
+)
+
+// MiddlewareHandler - useful to chain different middleware http.Handler
+type MiddlewareHandler func(http.Handler) http.Handler
+
+func registerCustomMiddleware(mux *router.Router, mwHandlers ...MiddlewareHandler) http.Handler {
+	var f http.Handler
+	f = mux
+	for _, mw := range mwHandlers {
+		f = mw(f)
+	}
+	return f
+}
+
+type timeHandler struct {
+	handler http.Handler
+}
+
+type resourceHandler struct {
+	handler http.Handler
+}
+
+func parseDate(req *http.Request) (time.Time, error) {
+	amzDate := req.Header.Get(http.CanonicalHeaderKey("x-amz-date"))
+	switch {
+	case amzDate != "":
+		if _, err := time.Parse(time.RFC1123, amzDate); err == nil {
+			return time.Parse(time.RFC1123, amzDate)
+		}
+		if _, err := time.Parse(time.RFC1123Z, amzDate); err == nil {
+			return time.Parse(time.RFC1123Z, amzDate)
+		}
+		if _, err := time.Parse(iso8601Format, amzDate); err == nil {
+			return time.Parse(iso8601Format, amzDate)
+		}
+	}
+	minioDate := req.Header.Get(http.CanonicalHeaderKey("x-minio-date"))
+	switch {
+	case minioDate != "":
+		if _, err := time.Parse(time.RFC1123, minioDate); err == nil {
+			return time.Parse(time.RFC1123, minioDate)
+		}
+		if _, err := time.Parse(time.RFC1123Z, minioDate); err == nil {
+			return time.Parse(time.RFC1123Z, minioDate)
+		}
+		if _, err := time.Parse(iso8601Format, minioDate); err == nil {
+			return time.Parse(iso8601Format, minioDate)
+		}
+	}
+	date := req.Header.Get("Date")
+	switch {
+	case date != "":
+		if _, err := time.Parse(time.RFC1123, date); err == nil {
+			return time.Parse(time.RFC1123, date)
+		}
+		if _, err := time.Parse(time.RFC1123Z, date); err == nil {
+			return time.Parse(time.RFC1123Z, date)
+		}
+		if _, err := time.Parse(iso8601Format, amzDate); err == nil {
+			return time.Parse(iso8601Format, amzDate)
+		}
+	}
+	return time.Time{}, errors.New("invalid request")
+}
+
+// TimeValidityHandler to validate parsable time over http header
+func TimeValidityHandler(h http.Handler) http.Handler {
+	return timeHandler{h}
+}
+
+func (h timeHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	// Verify if date headers are set, if not reject the request
+	if r.Header.Get("Authorization") != "" {
+		if r.Header.Get(http.CanonicalHeaderKey("x-amz-date")) == "" && r.Header.Get(http.CanonicalHeaderKey("x-minio-date")) == "" && r.Header.Get("Date") == "" {
+			// there is no way to knowing if this is a valid request, could be a attack reject such clients
+			writeErrorResponse(w, r, RequestTimeTooSkewed, r.URL.Path)
+			return
+		}
+		date, err := parseDate(r)
+		if err != nil {
+			// there is no way to knowing if this is a valid request, could be a attack reject such clients
+			writeErrorResponse(w, r, RequestTimeTooSkewed, r.URL.Path)
+			return
+		}
+		duration := time.Since(date)
+		minutes := time.Duration(5) * time.Minute
+		if duration.Minutes() > minutes.Minutes() {
+			writeErrorResponse(w, r, RequestTimeTooSkewed, r.URL.Path)
+			return
+		}
+	}
+	h.handler.ServeHTTP(w, r)
+}
+
+// CorsHandler handler for CORS (Cross Origin Resource Sharing)
+func CorsHandler(h http.Handler) http.Handler {
+	return cors.Default().Handler(h)
+}
+
+// IgnoreResourcesHandler -
+// Ignore resources handler is wrapper handler used for API request resource validation
+// Since we do not support all the S3 queries, it is necessary for us to throw back a
+// valid error message indicating such a feature is not implemented.
+func IgnoreResourcesHandler(h http.Handler) http.Handler {
+	return resourceHandler{h}
+}
+
+// Resource handler ServeHTTP() wrapper
+func (h resourceHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	splits := strings.SplitN(r.URL.Path, "/", 3)
+	switch len(splits) {
+	// bucket exists
+	case 2:
+		if ignoreNotImplementedBucketResources(r) {
+			writeErrorResponse(w, r, NotImplemented, r.URL.Path)
+			return
+		}
+	// object exists
+	case 3:
+		if ignoreNotImplementedObjectResources(r) {
+			writeErrorResponse(w, r, NotImplemented, r.URL.Path)
+			return
+		}
+	}
+	h.handler.ServeHTTP(w, r)
+}
+
+//// helpers
+
+// Checks requests for not implemented Bucket resources
+func ignoreNotImplementedBucketResources(req *http.Request) bool {
+	q := req.URL.Query()
+	for name := range q {
+		if notimplementedBucketResourceNames[name] {
+			return true
+		}
+	}
+	return false
+}
+
+// Checks requests for not implemented Object resources
+func ignoreNotImplementedObjectResources(req *http.Request) bool {
+	q := req.URL.Query()
+	for name := range q {
+		if notimplementedObjectResourceNames[name] {
+			return true
+		}
+	}
+	return false
+}