Add support for federation on browser (#6891)

cmd/generic-handlers.go

@@ -19,7 +19,6 @@ package cmd
 import (
 	"bufio"
 	"context"
-	"fmt"
 	"net"
 	"net/http"
 	"strings"
@@ -627,11 +626,52 @@ type bucketForwardingHandler struct {
 
 func (f bucketForwardingHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	if globalDNSConfig == nil || globalDomainName == "" ||
-		guessIsBrowserReq(r) || guessIsHealthCheckReq(r) ||
-		guessIsMetricsReq(r) || guessIsRPCReq(r) || isAdminReq(r) {
+		guessIsHealthCheckReq(r) || guessIsMetricsReq(r) ||
+		guessIsRPCReq(r) || isAdminReq(r) {
 		f.handler.ServeHTTP(w, r)
 		return
 	}
+
+	// For browser requests, when federation is setup we need to
+	// specifically handle download and upload for browser requests.
+	if guessIsBrowserReq(r) && globalDNSConfig != nil && globalDomainName != "" {
+		var bucket, _ string
+		switch r.Method {
+		case http.MethodPut:
+			if getRequestAuthType(r) == authTypeJWT {
+				bucket, _ = urlPath2BucketObjectName(strings.TrimPrefix(r.URL.Path, minioReservedBucketPath+"/upload"))
+			}
+		case http.MethodGet:
+			if t := r.URL.Query().Get("token"); t != "" {
+				bucket, _ = urlPath2BucketObjectName(strings.TrimPrefix(r.URL.Path, minioReservedBucketPath+"/download"))
+			} else if getRequestAuthType(r) != authTypeJWT && !strings.HasPrefix(r.URL.Path, minioReservedBucketPath) {
+				bucket, _ = urlPath2BucketObjectName(r.URL.Path)
+			}
+		}
+		if bucket != "" {
+			sr, err := globalDNSConfig.Get(bucket)
+			if err != nil {
+				if err == dns.ErrNoEntriesFound {
+					writeErrorResponse(w, ErrNoSuchBucket, r.URL, guessIsBrowserReq(r))
+				} else {
+					writeErrorResponse(w, toAPIErrorCode(context.Background(), err), r.URL, guessIsBrowserReq(r))
+				}
+				return
+			}
+			if globalDomainIPs.Intersection(set.CreateStringSet(getHostsSlice(sr)...)).IsEmpty() {
+				r.URL.Scheme = "http"
+				if globalIsSSL {
+					r.URL.Scheme = "https"
+				}
+				r.URL.Host = getHostFromSrv(sr)
+				f.fwd.ServeHTTP(w, r)
+				return
+			}
+		}
+		f.handler.ServeHTTP(w, r)
+		return
+	}
+
 	bucket, object := urlPath2BucketObjectName(r.URL.Path)
 	// ListBucket requests should be handled at current endpoint as
 	// all buckets data can be fetched from here.
@@ -663,12 +703,11 @@ func (f bucketForwardingHandler) ServeHTTP(w http.ResponseWriter, r *http.Reques
 		return
 	}
 	if globalDomainIPs.Intersection(set.CreateStringSet(getHostsSlice(sr)...)).IsEmpty() {
-		host, port := getRandomHostPort(sr)
 		r.URL.Scheme = "http"
 		if globalIsSSL {
 			r.URL.Scheme = "https"
 		}
-		r.URL.Host = fmt.Sprintf("%s:%d", host, port)
+		r.URL.Host = getHostFromSrv(sr)
 		f.fwd.ServeHTTP(w, r)
 		return
 	}

cmd/handler-utils.go

@@ -183,6 +183,13 @@ func getReqAccessCred(r *http.Request, region string) (cred auth.Credentials) {
 	if cred.AccessKey == "" {
 		cred, _, _ = getReqAccessKeyV2(r)
 	}
+	if cred.AccessKey == "" {
+		claims, owner, _ := webRequestAuthenticate(r)
+		if owner {
+			return globalServerConfig.GetCredential()
+		}
+		cred, _ = globalIAMSys.GetUser(claims.Subject)
+	}
 	return cred
 }
 
@@ -194,6 +201,7 @@ func extractReqParams(r *http.Request) map[string]string {
 
 	region := globalServerConfig.GetRegion()
 	cred := getReqAccessCred(r, region)
+
 	// Success.
 	return map[string]string{
 		"region":          region,

cmd/object-api-utils.go

@@ -23,6 +23,7 @@ import (
 	"fmt"
 	"io"
 	"math/rand"
+	"net"
 	"net/http"
 	"path"
 	"runtime"
@@ -299,11 +300,11 @@ func getHostsSlice(records []dns.SrvRecord) []string {
 	return hosts
 }
 
-// returns a random host (and corresponding port) from a slice of DNS records
-func getRandomHostPort(records []dns.SrvRecord) (string, int) {
+// returns a host (and corresponding port) from a slice of DNS records
+func getHostFromSrv(records []dns.SrvRecord) string {
 	rand.Seed(time.Now().Unix())
 	srvRecord := records[rand.Intn(len(records))]
-	return srvRecord.Host, srvRecord.Port
+	return net.JoinHostPort(srvRecord.Host, fmt.Sprintf("%d", srvRecord.Port))
 }
 
 // IsCompressed returns true if the object is marked as compressed.

cmd/object-handlers.go

@@ -668,11 +668,25 @@ func getCpObjMetadataFromHeader(ctx context.Context, r *http.Request, userMeta m
 
 // Returns a minio-go Client configured to access remote host described by destDNSRecord
 // Applicable only in a federated deployment
-var getRemoteInstanceClient = func(r *http.Request, host string, port int) (*miniogo.Core, error) {
-	// In a federated deployment, all the instances share config files and hence expected to have same
-	// credentials, make sure to send the same credentials for which the request came in.
+var getRemoteInstanceClient = func(r *http.Request, host string) (*miniogo.Core, error) {
 	cred := getReqAccessCred(r, globalServerConfig.GetRegion())
-	return miniogo.NewCore(net.JoinHostPort(host, strconv.Itoa(port)), cred.AccessKey, cred.SecretKey, globalIsSSL)
+	// In a federated deployment, all the instances share config files
+	// and hence expected to have same credentials.
+	core, err := miniogo.NewCore(host, cred.AccessKey, cred.SecretKey, globalIsSSL)
+	if err != nil {
+		return nil, err
+	}
+	core.SetCustomTransport(NewCustomHTTPTransport())
+	return core, nil
+}
+
+// Check if the bucket is on a remote site, this code only gets executed when federation is enabled.
+var isRemoteCallRequired = func(ctx context.Context, bucket string, objAPI ObjectLayer) bool {
+	if globalDNSConfig == nil {
+		return false
+	}
+	_, err := objAPI.GetBucketInfo(ctx, bucket)
+	return err == toObjectErr(errVolumeNotFound, bucket)
 }
 
 // CopyObjectHandler - Copy Object
@@ -802,17 +816,6 @@ func (api objectAPIHandlers) CopyObjectHandler(w http.ResponseWriter, r *http.Re
 		srcInfo.metadataOnly = true
 	}
 
-	// Checks if a remote putobject call is needed for CopyObject operation
-	// 1. If source and destination bucket names are same, it means no call needed to etcd to get destination info
-	// 2. If destination bucket doesn't exist locally, only then a etcd call is needed
-	var isRemoteCallRequired = func(ctx context.Context, src, dst string, objAPI ObjectLayer) bool {
-		if src == dst {
-			return false
-		}
-		_, berr := objAPI.GetBucketInfo(ctx, dst)
-		return berr == toObjectErr(errVolumeNotFound, dst)
-	}
-
 	var reader io.Reader
 	var length = srcInfo.Size
 
@@ -827,10 +830,27 @@ func (api objectAPIHandlers) CopyObjectHandler(w http.ResponseWriter, r *http.Re
 		length = actualSize
 	}
 
+	// Check if the destination bucket is on a remote site, this code only gets executed
+	// when federation is enabled, ie when globalDNSConfig is non 'nil'.
+	//
+	// This function is similar to isRemoteCallRequired but specifically for COPY object API
+	// if destination and source are same we do not need to check for destnation bucket
+	// to exist locally.
+	var isRemoteCopyRequired = func(ctx context.Context, srcBucket, dstBucket string, objAPI ObjectLayer) bool {
+		if globalDNSConfig == nil {
+			return false
+		}
+		if srcBucket == dstBucket {
+			return false
+		}
+		_, err := objAPI.GetBucketInfo(ctx, dstBucket)
+		return err == toObjectErr(errVolumeNotFound, dstBucket)
+	}
+
 	var compressMetadata map[string]string
 	// No need to compress for remote etcd calls
 	// Pass the decompressed stream to such calls.
-	isCompressed := objectAPI.IsCompressionSupported() && isCompressible(r.Header, srcObject) && !isRemoteCallRequired(ctx, srcBucket, dstBucket, objectAPI)
+	isCompressed := objectAPI.IsCompressionSupported() && isCompressible(r.Header, srcObject) && !isRemoteCopyRequired(ctx, srcBucket, dstBucket, objectAPI)
 	if isCompressed {
 		compressMetadata = make(map[string]string, 2)
 		// Preserving the compression metadata.
@@ -1009,29 +1029,28 @@ func (api objectAPIHandlers) CopyObjectHandler(w http.ResponseWriter, r *http.Re
 
 	var objInfo ObjectInfo
 
-	if isRemoteCallRequired(ctx, srcBucket, dstBucket, objectAPI) {
-		if globalDNSConfig == nil {
-			writeErrorResponse(w, ErrNoSuchBucket, r.URL, guessIsBrowserReq(r))
+	if isRemoteCopyRequired(ctx, srcBucket, dstBucket, objectAPI) {
+		var dstRecords []dns.SrvRecord
+		dstRecords, err = globalDNSConfig.Get(dstBucket)
+		if err != nil {
+			writeErrorResponse(w, toAPIErrorCode(ctx, err), r.URL, guessIsBrowserReq(r))
 			return
 		}
-		var dstRecords []dns.SrvRecord
-		if dstRecords, err = globalDNSConfig.Get(dstBucket); err == nil {
-			// Send PutObject request to appropriate instance (in federated deployment)
-			host, port := getRandomHostPort(dstRecords)
-			client, rerr := getRemoteInstanceClient(r, host, port)
-			if rerr != nil {
-				writeErrorResponse(w, toAPIErrorCode(ctx, rerr), r.URL, guessIsBrowserReq(r))
-				return
-			}
-			remoteObjInfo, rerr := client.PutObject(dstBucket, dstObject, srcInfo.Reader,
-				srcInfo.Size, "", "", srcInfo.UserDefined, dstOpts.ServerSideEncryption)
-			if rerr != nil {
-				writeErrorResponse(w, toAPIErrorCode(ctx, rerr), r.URL, guessIsBrowserReq(r))
-				return
-			}
-			objInfo.ETag = remoteObjInfo.ETag
-			objInfo.ModTime = remoteObjInfo.LastModified
+
+		// Send PutObject request to appropriate instance (in federated deployment)
+		client, rerr := getRemoteInstanceClient(r, getHostFromSrv(dstRecords))
+		if rerr != nil {
+			writeErrorResponse(w, toAPIErrorCode(ctx, rerr), r.URL, guessIsBrowserReq(r))
+			return
+		}
+		remoteObjInfo, rerr := client.PutObject(dstBucket, dstObject, srcInfo.Reader,
+			srcInfo.Size, "", "", srcInfo.UserDefined, dstOpts.ServerSideEncryption)
+		if rerr != nil {
+			writeErrorResponse(w, toAPIErrorCode(ctx, rerr), r.URL, guessIsBrowserReq(r))
+			return
 		}
+		objInfo.ETag = remoteObjInfo.ETag
+		objInfo.ModTime = remoteObjInfo.LastModified
 	} else {
 		// Copy source object to destination, if source and destination
 		// object is same then only metadata is updated.

cmd/web-handlers.go

@@ -99,11 +99,14 @@ func (web *webAPIHandlers) ServerInfo(r *http.Request, args *WebGenericArgs, rep
 	reply.MinioGlobalInfo = getGlobalInfo()
 	// If ENV creds are not set and incoming user is not owner
 	// disable changing credentials.
-	// TODO: fix this in future and allow changing user credentials.
 	v, ok := reply.MinioGlobalInfo["isEnvCreds"].(bool)
 	if ok && !v {
 		reply.MinioGlobalInfo["isEnvCreds"] = !owner
 	}
+	// if etcd is set disallow changing credentials through UI
+	if globalEtcdClient != nil {
+		reply.MinioGlobalInfo["isEnvCreds"] = true
+	}
 
 	reply.MinioMemory = mem
 	reply.MinioPlatform = platform
@@ -148,7 +151,7 @@ func (web *webAPIHandlers) MakeBucket(r *http.Request, args *MakeBucketArgs, rep
 	if authErr != nil {
 		return toJSONError(authErr)
 	}
-	// TODO: Allow MakeBucket in future.
+
 	if !owner {
 		return toJSONError(errAccessDenied)
 	}
@@ -201,11 +204,33 @@ func (web *webAPIHandlers) DeleteBucket(r *http.Request, args *RemoveBucketArgs,
 	if authErr != nil {
 		return toJSONError(authErr)
 	}
-	// TODO: Allow DeleteBucket in future.
+
 	if !owner {
 		return toJSONError(errAccessDenied)
 	}
 
+	reply.UIVersion = browser.UIVersion
+
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
+			return toJSONError(err, args.BucketName)
+		}
+		core, err := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		if err = core.RemoveBucket(args.BucketName); err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		return nil
+	}
+
 	ctx := context.Background()
 
 	deleteBucket := objectAPI.DeleteBucket
@@ -229,7 +254,6 @@ func (web *webAPIHandlers) DeleteBucket(r *http.Request, args *RemoveBucketArgs,
 		}
 	}
 
-	reply.UIVersion = browser.UIVersion
 	return nil
 }
 
@@ -353,6 +377,42 @@ func (web *webAPIHandlers) ListObjects(r *http.Request, args *ListObjectsArgs, r
 		listObjects = web.CacheAPI().ListObjects
 	}
 
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
+			return toJSONError(err, args.BucketName)
+		}
+		core, err := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		result, err := core.ListObjects(args.BucketName, args.Prefix, args.Marker, slashSeparator, 1000)
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		reply.NextMarker = result.NextMarker
+		reply.IsTruncated = result.IsTruncated
+		for _, obj := range result.Contents {
+			reply.Objects = append(reply.Objects, WebObjectInfo{
+				Key:          obj.Key,
+				LastModified: obj.LastModified,
+				Size:         obj.Size,
+				ContentType:  obj.ContentType,
+			})
+		}
+		for _, p := range result.CommonPrefixes {
+			reply.Objects = append(reply.Objects, WebObjectInfo{
+				Key: p.Prefix,
+			})
+		}
+		return nil
+	}
+
 	claims, owner, authErr := webRequestAuthenticate(r)
 	if authErr != nil {
 		if authErr == errNoAuthToken {
@@ -493,6 +553,40 @@ func (web *webAPIHandlers) RemoveObject(r *http.Request, args *RemoveObjectArgs,
 		return toJSONError(errInvalidArgument)
 	}
 
+	reply.UIVersion = browser.UIVersion
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
+			return toJSONError(err, args.BucketName)
+		}
+		core, err := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		objectsCh := make(chan string)
+
+		// Send object names that are needed to be removed to objectsCh
+		go func() {
+			defer close(objectsCh)
+
+			for _, objectName := range args.Objects {
+				objectsCh <- objectName
+			}
+		}()
+
+		for resp := range core.RemoveObjects(args.BucketName, objectsCh) {
+			if resp.Err != nil {
+				return toJSONError(resp.Err, args.BucketName, resp.ObjectName)
+			}
+		}
+		return nil
+	}
+
 	var err error
 next:
 	for _, objectName := range args.Objects {
@@ -516,7 +610,7 @@ next:
 				return toJSONError(errAccessDenied)
 			}
 
-			if err = deleteObject(nil, objectAPI, web.CacheAPI(), args.BucketName, objectName, r); err != nil {
+			if err = deleteObject(context.Background(), objectAPI, web.CacheAPI(), args.BucketName, objectName, r); err != nil {
 				break next
 			}
 			continue
@@ -543,7 +637,7 @@ next:
 			}
 			marker = lo.NextMarker
 			for _, obj := range lo.Objects {
-				err = deleteObject(nil, objectAPI, web.CacheAPI(), args.BucketName, obj.Name, r)
+				err = deleteObject(context.Background(), objectAPI, web.CacheAPI(), args.BucketName, obj.Name, r)
 				if err != nil {
 					break next
 				}
@@ -559,7 +653,6 @@ next:
 		return toJSONError(err, args.BucketName, "")
 	}
 
-	reply.UIVersion = browser.UIVersion
 	return nil
 }
 
@@ -633,8 +726,7 @@ func (web *webAPIHandlers) SetAuth(r *http.Request, args *SetAuthArgs, reply *Se
 	}
 
 	// If creds are set through ENV disallow changing credentials.
-	// TODO: Multi-user credentials also cannot be changed from browser.
-	if globalIsEnvCreds || globalWORMEnabled || !owner {
+	if globalIsEnvCreds || globalWORMEnabled || !owner || globalEtcdClient != nil {
 		return toJSONError(errChangeCredNotAllowed)
 	}
 
@@ -858,6 +950,7 @@ func (web *webAPIHandlers) Upload(w http.ResponseWriter, r *http.Request) {
 			pReader = NewPutObjReader(rawReader, hashReader, objectEncryptionKey)
 		}
 	}
+
 	// Ensure that metadata does not contain sensitive information
 	crypto.RemoveSensitiveEntries(metadata)
 
@@ -1306,18 +1399,48 @@ func (web *webAPIHandlers) GetBucketPolicy(r *http.Request, args *GetBucketPolic
 		return toJSONError(errAccessDenied)
 	}
 
-	bucketPolicy, err := objectAPI.GetBucketPolicy(context.Background(), args.BucketName)
-	if err != nil {
-		if _, ok := err.(BucketPolicyNotFound); !ok {
+	var policyInfo = &miniogopolicy.BucketAccessPolicy{Version: "2012-10-17"}
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
 			return toJSONError(err, args.BucketName)
 		}
-		return err
-	}
+		client, rerr := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if rerr != nil {
+			return toJSONError(rerr, args.BucketName)
+		}
+		policyStr, err := client.GetBucketPolicy(args.BucketName)
+		if err != nil {
+			return toJSONError(rerr, args.BucketName)
+		}
+		bucketPolicy, err := policy.ParseConfig(strings.NewReader(policyStr), args.BucketName)
+		if err != nil {
+			return toJSONError(rerr, args.BucketName)
+		}
+		policyInfo, err = PolicyToBucketAccessPolicy(bucketPolicy)
+		if err != nil {
+			// This should not happen.
+			return toJSONError(err, args.BucketName)
+		}
+	} else {
+		bucketPolicy, err := objectAPI.GetBucketPolicy(context.Background(), args.BucketName)
+		if err != nil {
+			if _, ok := err.(BucketPolicyNotFound); !ok {
+				return toJSONError(err, args.BucketName)
+			}
+			return err
+		}
 
-	policyInfo, err := PolicyToBucketAccessPolicy(bucketPolicy)
-	if err != nil {
-		// This should not happen.
-		return toJSONError(err, args.BucketName)
+		policyInfo, err = PolicyToBucketAccessPolicy(bucketPolicy)
+		if err != nil {
+			// This should not happen.
+			return toJSONError(err, args.BucketName)
+		}
 	}
 
 	reply.UIVersion = browser.UIVersion
@@ -1359,17 +1482,42 @@ func (web *webAPIHandlers) ListAllBucketPolicies(r *http.Request, args *ListAllB
 		return toJSONError(errAccessDenied)
 	}
 
-	bucketPolicy, err := objectAPI.GetBucketPolicy(context.Background(), args.BucketName)
-	if err != nil {
-		if _, ok := err.(BucketPolicyNotFound); !ok {
+	var policyInfo = new(miniogopolicy.BucketAccessPolicy)
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
+			return toJSONError(err, args.BucketName)
+		}
+		core, rerr := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if rerr != nil {
+			return toJSONError(rerr, args.BucketName)
+		}
+		var policyStr string
+		policyStr, err = core.Client.GetBucketPolicy(args.BucketName)
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		if policyStr != "" {
+			if err = json.Unmarshal([]byte(policyStr), policyInfo); err != nil {
+				return toJSONError(err, args.BucketName)
+			}
+		}
+	} else {
+		bucketPolicy, err := objectAPI.GetBucketPolicy(context.Background(), args.BucketName)
+		if err != nil {
+			if _, ok := err.(BucketPolicyNotFound); !ok {
+				return toJSONError(err, args.BucketName)
+			}
+		}
+		policyInfo, err = PolicyToBucketAccessPolicy(bucketPolicy)
+		if err != nil {
 			return toJSONError(err, args.BucketName)
 		}
-	}
-
-	policyInfo, err := PolicyToBucketAccessPolicy(bucketPolicy)
-	if err != nil {
-		// This should not happen.
-		return toJSONError(err, args.BucketName)
 	}
 
 	reply.UIVersion = browser.UIVersion
@@ -1419,43 +1567,94 @@ func (web *webAPIHandlers) SetBucketPolicy(r *http.Request, args *SetBucketPolic
 
 	ctx := context.Background()
 
-	bucketPolicy, err := objectAPI.GetBucketPolicy(ctx, args.BucketName)
-	if err != nil {
-		if _, ok := err.(BucketPolicyNotFound); !ok {
+	if isRemoteCallRequired(context.Background(), args.BucketName, objectAPI) {
+		sr, err := globalDNSConfig.Get(args.BucketName)
+		if err != nil {
+			if err == dns.ErrNoEntriesFound {
+				return toJSONError(BucketNotFound{
+					Bucket: args.BucketName,
+				}, args.BucketName)
+			}
 			return toJSONError(err, args.BucketName)
 		}
-	}
+		core, rerr := getRemoteInstanceClient(r, getHostFromSrv(sr))
+		if rerr != nil {
+			return toJSONError(rerr, args.BucketName)
+		}
+		var policyStr string
+		// Use the abstracted API instead of core, such that
+		// NoSuchBucketPolicy errors are automatically handled.
+		policyStr, err = core.Client.GetBucketPolicy(args.BucketName)
+		if err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+		var policyInfo = &miniogopolicy.BucketAccessPolicy{Version: "2012-10-17"}
+		if policyStr != "" {
+			if err = json.Unmarshal([]byte(policyStr), policyInfo); err != nil {
+				return toJSONError(err, args.BucketName)
+			}
+		}
 
-	policyInfo, err := PolicyToBucketAccessPolicy(bucketPolicy)
-	if err != nil {
-		// This should not happen.
-		return toJSONError(err, args.BucketName)
-	}
+		policyInfo.Statements = miniogopolicy.SetPolicy(policyInfo.Statements, policyType, args.BucketName, args.Prefix)
+		if len(policyInfo.Statements) == 0 {
+			if err = core.SetBucketPolicy(args.BucketName, ""); err != nil {
+				return toJSONError(err, args.BucketName)
+			}
+			return nil
+		}
 
-	policyInfo.Statements = miniogopolicy.SetPolicy(policyInfo.Statements, policyType, args.BucketName, args.Prefix)
+		bucketPolicy, err := BucketAccessPolicyToPolicy(policyInfo)
+		if err != nil {
+			// This should not happen.
+			return toJSONError(err, args.BucketName)
+		}
 
-	if len(policyInfo.Statements) == 0 {
-		if err = objectAPI.DeleteBucketPolicy(ctx, args.BucketName); err != nil {
+		policyData, err := json.Marshal(bucketPolicy)
+		if err != nil {
 			return toJSONError(err, args.BucketName)
 		}
 
-		globalPolicySys.Remove(args.BucketName)
-		return nil
-	}
+		if err = core.SetBucketPolicy(args.BucketName, string(policyData)); err != nil {
+			return toJSONError(err, args.BucketName)
+		}
 
-	bucketPolicy, err = BucketAccessPolicyToPolicy(policyInfo)
-	if err != nil {
-		// This should not happen.
-		return toJSONError(err, args.BucketName)
-	}
+	} else {
+		bucketPolicy, err := objectAPI.GetBucketPolicy(ctx, args.BucketName)
+		if err != nil {
+			if _, ok := err.(BucketPolicyNotFound); !ok {
+				return toJSONError(err, args.BucketName)
+			}
+		}
+		policyInfo, err := PolicyToBucketAccessPolicy(bucketPolicy)
+		if err != nil {
+			// This should not happen.
+			return toJSONError(err, args.BucketName)
+		}
 
-	// Parse validate and save bucket policy.
-	if err := objectAPI.SetBucketPolicy(ctx, args.BucketName, bucketPolicy); err != nil {
-		return toJSONError(err, args.BucketName)
-	}
+		policyInfo.Statements = miniogopolicy.SetPolicy(policyInfo.Statements, policyType, args.BucketName, args.Prefix)
+		if len(policyInfo.Statements) == 0 {
+			if err = objectAPI.DeleteBucketPolicy(ctx, args.BucketName); err != nil {
+				return toJSONError(err, args.BucketName)
+			}
+
+			globalPolicySys.Remove(args.BucketName)
+			return nil
+		}
+
+		bucketPolicy, err = BucketAccessPolicyToPolicy(policyInfo)
+		if err != nil {
+			// This should not happen.
+			return toJSONError(err, args.BucketName)
+		}
 
-	globalPolicySys.Set(args.BucketName, *bucketPolicy)
-	globalNotificationSys.SetBucketPolicy(ctx, args.BucketName, bucketPolicy)
+		// Parse validate and save bucket policy.
+		if err := objectAPI.SetBucketPolicy(ctx, args.BucketName, bucketPolicy); err != nil {
+			return toJSONError(err, args.BucketName)
+		}
+
+		globalPolicySys.Set(args.BucketName, *bucketPolicy)
+		globalNotificationSys.SetBucketPolicy(ctx, args.BucketName, bucketPolicy)
+	}
 
 	return nil
 }

cmd/web-router.go

@@ -89,7 +89,7 @@ func registerWebRouter(router *mux.Router) error {
 
 	// These methods use short-expiry tokens in the URLs. These tokens may unintentionally
 	// be logged, so a new one must be generated for each request.
-	webBrowserRouter.Methods("GET").Path("/download/{bucket}/{object:.+}").Queries("token", "{token:.*}").HandlerFunc(web.Download)
+	webBrowserRouter.Methods("GET").Path("/download/{bucket}/{object:.+}").Queries("token", "{token:.*}").HandlerFunc(httpTraceHdrs(web.Download))
 	webBrowserRouter.Methods("POST").Path("/zip").Queries("token", "{token:.*}").HandlerFunc(httpTraceHdrs(web.DownloadZip))
 
 	// Add compression for assets.