api: CopyObjectPart was copying wrong offsets due to shadowing. (#3838)

startOffset was re-assigned to '0' so it would end up
copying wrong content ignoring the requested startOffset.

This also fixes the corruption issue we observed while
using docker registry.

Fixes https://github.com/docker/distribution/issues/2205

Also fixes #3842 - incorrect routing.

cmd/api-errors.go

@@ -56,6 +56,8 @@ const (
 	ErrInvalidBucketName
 	ErrInvalidDigest
 	ErrInvalidRange
+	ErrInvalidCopyPartRange
+	ErrInvalidCopyPartRangeSource
 	ErrInvalidMaxKeys
 	ErrInvalidMaxUploads
 	ErrInvalidMaxParts
@@ -540,6 +542,16 @@ var errorCodeResponse = map[APIErrorCode]APIError{
 		Description:    "Configurations overlap. Configurations on the same bucket cannot share a common event type.",
 		HTTPStatusCode: http.StatusBadRequest,
 	},
+	ErrInvalidCopyPartRange: {
+		Code:           "InvalidArgument",
+		Description:    "The x-amz-copy-source-range value must be of the form bytes=first-last where first and last are the zero-based offsets of the first and last bytes to copy",
+		HTTPStatusCode: http.StatusBadRequest,
+	},
+	ErrInvalidCopyPartRangeSource: {
+		Code:           "InvalidArgument",
+		Description:    "Range specified is not valid for source object",
+		HTTPStatusCode: http.StatusBadRequest,
+	},
 
 	/// S3 extensions.
 	ErrContentSHA256Mismatch: {

cmd/copy-part-range.go

@@ -0,0 +1,106 @@
+/*
+ * Minio Cloud Storage, (C) 2017 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"
+	"net/http"
+	"net/url"
+	"strconv"
+	"strings"
+)
+
+// Writes S3 compatible copy part range error.
+func writeCopyPartErr(w http.ResponseWriter, err error, url *url.URL) {
+	switch err {
+	case errInvalidRange:
+		writeErrorResponse(w, ErrInvalidCopyPartRange, url)
+		return
+	case errInvalidRangeSource:
+		writeErrorResponse(w, ErrInvalidCopyPartRangeSource, url)
+		return
+	default:
+		writeErrorResponse(w, ErrInternalError, url)
+		return
+	}
+}
+
+// Parses x-amz-copy-source-range for CopyObjectPart API. Specifically written to
+// differentiate the behavior between regular httpRange header v/s x-amz-copy-source-range.
+// The range of bytes to copy from the source object. The range value must use the form
+// bytes=first-last, where the first and last are the zero-based byte offsets to copy.
+// For example, bytes=0-9 indicates that you want to copy the first ten bytes of the source.
+// http://docs.aws.amazon.com/AmazonS3/latest/API/mpUploadUploadPartCopy.html
+func parseCopyPartRange(rangeString string, resourceSize int64) (hrange *httpRange, err error) {
+	// Return error if given range string doesn't start with byte range prefix.
+	if !strings.HasPrefix(rangeString, byteRangePrefix) {
+		return nil, fmt.Errorf("'%s' does not start with '%s'", rangeString, byteRangePrefix)
+	}
+
+	// Trim byte range prefix.
+	byteRangeString := strings.TrimPrefix(rangeString, byteRangePrefix)
+
+	// Check if range string contains delimiter '-', else return error. eg. "bytes=8"
+	sepIndex := strings.Index(byteRangeString, "-")
+	if sepIndex == -1 {
+		return nil, errInvalidRange
+	}
+
+	offsetBeginString := byteRangeString[:sepIndex]
+	offsetBegin := int64(-1)
+	// Convert offsetBeginString only if its not empty.
+	if len(offsetBeginString) > 0 {
+		if !validBytePos.MatchString(offsetBeginString) {
+			return nil, errInvalidRange
+		}
+		if offsetBegin, err = strconv.ParseInt(offsetBeginString, 10, 64); err != nil {
+			return nil, errInvalidRange
+		}
+	}
+
+	offsetEndString := byteRangeString[sepIndex+1:]
+	offsetEnd := int64(-1)
+	// Convert offsetEndString only if its not empty.
+	if len(offsetEndString) > 0 {
+		if !validBytePos.MatchString(offsetEndString) {
+			return nil, errInvalidRange
+		}
+		if offsetEnd, err = strconv.ParseInt(offsetEndString, 10, 64); err != nil {
+			return nil, errInvalidRange
+		}
+	}
+
+	// rangeString contains first byte positions. eg. "bytes=2-" or
+	// rangeString contains last bye positions. eg. "bytes=-2"
+	if offsetBegin == -1 || offsetEnd == -1 {
+		return nil, errInvalidRange
+	}
+
+	// Last byte position should not be greater than first byte
+	// position. eg. "bytes=5-2"
+	if offsetBegin > offsetEnd {
+		return nil, errInvalidRange
+	}
+
+	// First and last byte positions should not be >= resourceSize.
+	if offsetBegin >= resourceSize || offsetEnd >= resourceSize {
+		return nil, errInvalidRangeSource
+	}
+
+	// Success..
+	return &httpRange{offsetBegin, offsetEnd, resourceSize}, nil
+}

cmd/copy-part-range_test.go

@@ -0,0 +1,85 @@
+/*
+ * Minio Cloud Storage, (C) 2017 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 "testing"
+
+// Test parseCopyPartRange()
+func TestParseCopyPartRange(t *testing.T) {
+	// Test success cases.
+	successCases := []struct {
+		rangeString string
+		offsetBegin int64
+		offsetEnd   int64
+		length      int64
+	}{
+		{"bytes=2-5", 2, 5, 4},
+		{"bytes=2-9", 2, 9, 8},
+		{"bytes=2-2", 2, 2, 1},
+		{"bytes=0000-0006", 0, 6, 7},
+	}
+
+	for _, successCase := range successCases {
+		hrange, err := parseCopyPartRange(successCase.rangeString, 10)
+		if err != nil {
+			t.Fatalf("expected: <nil>, got: %s", err)
+		}
+
+		if hrange.offsetBegin != successCase.offsetBegin {
+			t.Fatalf("expected: %d, got: %d", successCase.offsetBegin, hrange.offsetBegin)
+		}
+
+		if hrange.offsetEnd != successCase.offsetEnd {
+			t.Fatalf("expected: %d, got: %d", successCase.offsetEnd, hrange.offsetEnd)
+		}
+		if hrange.getLength() != successCase.length {
+			t.Fatalf("expected: %d, got: %d", successCase.length, hrange.getLength())
+		}
+	}
+
+	// Test invalid range strings.
+	invalidRangeStrings := []string{
+		"bytes=8",
+		"bytes=5-2",
+		"bytes=+2-5",
+		"bytes=2-+5",
+		"bytes=2--5",
+		"bytes=-",
+		"",
+		"2-5",
+		"bytes = 2-5",
+		"bytes=2 - 5",
+		"bytes=0-0,-1",
+		"bytes=2-5 ",
+	}
+	for _, rangeString := range invalidRangeStrings {
+		if _, err := parseCopyPartRange(rangeString, 10); err == nil {
+			t.Fatalf("expected: an error, got: <nil> for range %s", rangeString)
+		}
+	}
+
+	// Test error range strings.
+	errorRangeString := []string{
+		"bytes=10-10",
+		"bytes=20-30",
+	}
+	for _, rangeString := range errorRangeString {
+		if _, err := parseCopyPartRange(rangeString, 10); err != errInvalidRangeSource {
+			t.Fatalf("expected: %s, got: %s", errInvalidRangeSource, err)
+		}
+	}
+}

cmd/fs-v1-multipart.go

@@ -463,7 +463,6 @@ func (fs fsObjects) CopyObjectPart(srcBucket, srcObject, dstBucket, dstObject, u
 	pipeReader, pipeWriter := io.Pipe()
 
 	go func() {
-		var startOffset int64 // Read the whole file.
 		if gerr := fs.GetObject(srcBucket, srcObject, startOffset, length, pipeWriter); gerr != nil {
 			errorIf(gerr, "Unable to read %s/%s.", srcBucket, srcObject)
 			pipeWriter.CloseWithError(gerr)

cmd/object-api-errors.go

@@ -17,7 +17,6 @@
 package cmd
 
 import (
-	"errors"
 	"fmt"
 	"io"
 )
@@ -252,9 +251,6 @@ func (e IncompleteBody) Error() string {
 	return e.Bucket + "#" + e.Object + "has incomplete body"
 }
 
-// errInvalidRange - returned when given range value is not valid.
-var errInvalidRange = errors.New("Invalid range")
-
 // InvalidRange - invalid range typed error.
 type InvalidRange struct {
 	offsetBegin  int64

cmd/object-handlers.go

@@ -601,17 +601,13 @@ func (api objectAPIHandlers) CopyObjectPartHandler(w http.ResponseWriter, r *htt
 	var hrange *httpRange
 	rangeHeader := r.Header.Get("x-amz-copy-source-range")
 	if rangeHeader != "" {
-		if hrange, err = parseRequestRange(rangeHeader, objInfo.Size); err != nil {
+		if hrange, err = parseCopyPartRange(rangeHeader, objInfo.Size); err != nil {
 			// Handle only errInvalidRange
 			// Ignore other parse error and treat it as regular Get request like Amazon S3.
-			if err == errInvalidRange {
-				writeErrorResponse(w, ErrInvalidRange, r.URL)
+			errorIf(err, "Unable to extract range %s", rangeHeader)
+			writeCopyPartErr(w, err, r.URL)
 			return
 		}
-
-			// log the error.
-			errorIf(err, "Invalid request range")
-		}
 	}
 
 	// Verify before x-amz-copy-source preconditions before continuing with CopyObject.
@@ -623,8 +619,8 @@ func (api objectAPIHandlers) CopyObjectPartHandler(w http.ResponseWriter, r *htt
 	var startOffset int64
 	length := objInfo.Size
 	if hrange != nil {
-		startOffset = hrange.offsetBegin
 		length = hrange.getLength()
+		startOffset = hrange.offsetBegin
 	}
 
 	/// maximum copy size for multipart objects in a single operation
@@ -661,6 +657,12 @@ func (api objectAPIHandlers) PutObjectPartHandler(w http.ResponseWriter, r *http
 		return
 	}
 
+	// X-Amz-Copy-Source shouldn't be set for this call.
+	if _, ok := r.Header["X-Amz-Copy-Source"]; ok {
+		writeErrorResponse(w, ErrInvalidCopySource, r.URL)
+		return
+	}
+
 	// get Content-Md5 sent by client and verify if valid
 	md5Bytes, err := checkValidMD5(r.Header.Get("Content-Md5"))
 	if err != nil {

cmd/object-handlers_test.go

@@ -26,6 +26,7 @@ import (
 	"net/http/httptest"
 	"net/url"
 	"strconv"
+	"strings"
 	"sync"
 	"testing"
 
@@ -939,6 +940,124 @@ func testAPIPutObjectHandler(obj ObjectLayer, instanceType, bucketName string, a
 
 }
 
+// Tests sanity of attempting to copying each parts at offsets from an existing
+// file and create a new object. Also validates if the written is same as what we
+// expected.
+func TestAPICopyObjectPartHandlerSanity(t *testing.T) {
+	defer DetectTestLeak(t)()
+	ExecObjectLayerAPITest(t, testAPICopyObjectPartHandlerSanity, []string{"CopyObjectPart"})
+}
+
+func testAPICopyObjectPartHandlerSanity(obj ObjectLayer, instanceType, bucketName string, apiRouter http.Handler,
+	credentials credential, t *testing.T) {
+
+	objectName := "test-object"
+	// register event notifier.
+	err := initEventNotifier(obj)
+	if err != nil {
+		t.Fatalf("Initializing event notifiers failed")
+	}
+
+	// set of byte data for PutObject.
+	// object has to be created before running tests for Copy Object.
+	// this is required even to assert the copied object,
+	bytesData := []struct {
+		byteData []byte
+	}{
+		{generateBytesData(6 * humanize.MiByte)},
+	}
+
+	// set of inputs for uploading the objects before tests for downloading is done.
+	putObjectInputs := []struct {
+		bucketName    string
+		objectName    string
+		contentLength int64
+		textData      []byte
+		metaData      map[string]string
+	}{
+		// case - 1.
+		{bucketName, objectName, int64(len(bytesData[0].byteData)), bytesData[0].byteData, make(map[string]string)},
+	}
+	sha256sum := ""
+	// iterate through the above set of inputs and upload the object.
+	for i, input := range putObjectInputs {
+		// uploading the object.
+		_, err = obj.PutObject(input.bucketName, input.objectName, input.contentLength,
+			bytes.NewBuffer(input.textData), input.metaData, sha256sum)
+		// if object upload fails stop the test.
+		if err != nil {
+			t.Fatalf("Put Object case %d:  Error uploading object: <ERROR> %v", i+1, err)
+		}
+	}
+
+	// Initiate Multipart upload for testing PutObjectPartHandler.
+	testObject := "testobject"
+
+	// PutObjectPart API HTTP Handler has to be tested in isolation,
+	// that is without any other handler being registered,
+	// That's why NewMultipartUpload is initiated using ObjectLayer.
+	uploadID, err := obj.NewMultipartUpload(bucketName, testObject, nil)
+	if err != nil {
+		// Failed to create NewMultipartUpload, abort.
+		t.Fatalf("Minio %s : <ERROR>  %s", instanceType, err)
+	}
+
+	a := 0
+	b := globalMinPartSize - 1
+	var parts []completePart
+	for partNumber := 1; partNumber <= 2; partNumber++ {
+		// initialize HTTP NewRecorder, this records any mutations to response writer inside the handler.
+		rec := httptest.NewRecorder()
+		cpPartURL := getCopyObjectPartURL("", bucketName, testObject, uploadID, fmt.Sprintf("%d", partNumber))
+
+		// construct HTTP request for copy object.
+		var req *http.Request
+		req, err = newTestSignedRequestV4("PUT", cpPartURL, 0, nil, credentials.AccessKey, credentials.SecretKey)
+		if err != nil {
+			t.Fatalf("Test failed to create HTTP request for copy object part: <ERROR> %v", err)
+		}
+
+		// "X-Amz-Copy-Source" header contains the information about the source bucket and the object to copied.
+		req.Header.Set("X-Amz-Copy-Source", url.QueryEscape(pathJoin(bucketName, objectName)))
+		req.Header.Set("X-Amz-Copy-Source-Range", fmt.Sprintf("bytes=%d-%d", a, b))
+
+		// Since `apiRouter` satisfies `http.Handler` it has a ServeHTTP to execute the logic of the handler.
+		// Call the ServeHTTP to execute the handler, `func (api objectAPIHandlers) CopyObjectHandler` handles the request.
+		a = globalMinPartSize
+		b = len(bytesData[0].byteData) - 1
+		apiRouter.ServeHTTP(rec, req)
+		if rec.Code != http.StatusOK {
+			t.Fatalf("Test failed to create HTTP request for copy %d", rec.Code)
+		}
+
+		resp := &CopyObjectPartResponse{}
+		if err = xmlDecoder(rec.Body, resp, rec.Result().ContentLength); err != nil {
+			t.Fatalf("Test failed to decode XML response: <ERROR> %v", err)
+		}
+
+		parts = append(parts, completePart{
+			PartNumber: partNumber,
+			ETag:       strings.Trim(resp.ETag, "\""),
+		})
+	}
+
+	result, err := obj.CompleteMultipartUpload(bucketName, testObject, uploadID, parts)
+	if err != nil {
+		t.Fatalf("Test: %s complete multipart upload failed: <ERROR> %v", instanceType, err)
+	}
+	if result.Size != int64(len(bytesData[0].byteData)) {
+		t.Fatalf("Test: %s expected size not written: expected %d, got %d", instanceType, len(bytesData[0].byteData), result.Size)
+	}
+
+	var buf bytes.Buffer
+	if err = obj.GetObject(bucketName, testObject, 0, int64(len(bytesData[0].byteData)), &buf); err != nil {
+		t.Fatalf("Test: %s reading completed file failed: <ERROR> %v", instanceType, err)
+	}
+	if !bytes.Equal(buf.Bytes(), bytesData[0].byteData) {
+		t.Fatalf("Test: %s returned data is not expected corruption detected:", instanceType)
+	}
+}
+
 // Wrapper for calling Copy Object Part API handler tests for both XL multiple disks and single node setup.
 func TestAPICopyObjectPartHandler(t *testing.T) {
 	defer DetectTestLeak(t)()
@@ -1069,10 +1188,23 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			accessKey:        credentials.AccessKey,
 			secretKey:        credentials.SecretKey,
 
-			expectedRespStatus: http.StatusRequestedRangeNotSatisfiable,
+			expectedRespStatus: http.StatusBadRequest,
 		},
 
 		// Test case - 6.
+		// Test case with ivalid byte range for exceeding source size boundaries.
+		{
+			bucketName:       bucketName,
+			uploadID:         uploadID,
+			copySourceHeader: url.QueryEscape("/" + bucketName + "/" + objectName),
+			copySourceRange:  "bytes=0-6144",
+			accessKey:        credentials.AccessKey,
+			secretKey:        credentials.SecretKey,
+
+			expectedRespStatus: http.StatusBadRequest,
+		},
+
+		// Test case - 7.
 		// Test case with object name missing from source.
 		// fail with BadRequest.
 		{
@@ -1085,7 +1217,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			expectedRespStatus: http.StatusBadRequest,
 		},
 
-		// Test case - 7.
+		// Test case - 8.
 		// Test case with non-existent source file.
 		// Case for the purpose of failing `api.ObjectAPI.GetObjectInfo`.
 		// Expecting the response status code to http.StatusNotFound (404).
@@ -1099,7 +1231,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			expectedRespStatus: http.StatusNotFound,
 		},
 
-		// Test case - 8.
+		// Test case - 9.
 		// Test case with non-existent source file.
 		// Case for the purpose of failing `api.ObjectAPI.PutObjectPart`.
 		// Expecting the response status code to http.StatusNotFound (404).
@@ -1113,7 +1245,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			expectedRespStatus: http.StatusNotFound,
 		},
 
-		// Test case - 9.
+		// Test case - 10.
 		// Case with invalid AccessKey.
 		{
 			bucketName:       bucketName,
@@ -1125,7 +1257,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			expectedRespStatus: http.StatusForbidden,
 		},
 
-		// Test case - 10.
+		// Test case - 11.
 		// Case with non-existent upload id.
 		{
 			bucketName:       bucketName,
@@ -1136,7 +1268,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 
 			expectedRespStatus: http.StatusNotFound,
 		},
-		// Test case - 11.
+		// Test case - 12.
 		// invalid part number.
 		{
 			bucketName:         bucketName,
@@ -1147,7 +1279,7 @@ func testAPICopyObjectPartHandler(obj ObjectLayer, instanceType, bucketName stri
 			secretKey:          credentials.SecretKey,
 			expectedRespStatus: http.StatusOK,
 		},
-		// Test case - 12.
+		// Test case - 13.
 		// maximum part number.
 		{
 			bucketName:         bucketName,

cmd/typed-errors.go

@@ -54,3 +54,10 @@ var errServerTimeMismatch = errors.New("Server times are too far apart")
 // errReservedBucket - bucket name is reserved for Minio, usually
 // returned for 'minio', '.minio.sys'
 var errReservedBucket = errors.New("All access to this bucket is disabled")
+
+// errInvalidRange - returned when given range value is not valid.
+var errInvalidRange = errors.New("Invalid range")
+
+// errInvalidRangeSource - returned when given range value exceeds
+// the source object size.
+var errInvalidRangeSource = errors.New("Range specified exceeds source object size")

cmd/xl-v1-multipart.go

@@ -546,7 +546,6 @@ func (xl xlObjects) CopyObjectPart(srcBucket, srcObject, dstBucket, dstObject, u
 	pipeReader, pipeWriter := io.Pipe()
 
 	go func() {
-		var startOffset int64 // Read the whole file.
 		if gerr := xl.GetObject(srcBucket, srcObject, startOffset, length, pipeWriter); gerr != nil {
 			errorIf(gerr, "Unable to read %s of the object `%s/%s`.", srcBucket, srcObject)
 			pipeWriter.CloseWithError(toObjectErr(gerr, srcBucket, srcObject))