/* * MinIO Go Library for Amazon S3 Compatible Cloud Storage * Copyright 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 minio import ( "bytes" "context" "encoding/base64" "fmt" "io" "net/http" "net/url" "sort" "strings" "sync" "github.com/google/uuid" "github.com/minio/minio-go/v7/pkg/s3utils" ) // putObjectMultipartStream - upload a large object using // multipart upload and streaming signature for signing payload. // Comprehensive put object operation involving multipart uploads. // // Following code handles these types of readers. // // - *minio.Object // - Any reader which has a method 'ReadAt()' func (c *Client) putObjectMultipartStream(ctx context.Context, bucketName, objectName string, reader io.Reader, size int64, opts PutObjectOptions, ) (info UploadInfo, err error) { if opts.ConcurrentStreamParts && opts.NumThreads > 1 { info, err = c.putObjectMultipartStreamParallel(ctx, bucketName, objectName, reader, opts) } else if !isObject(reader) && isReadAt(reader) && !opts.SendContentMd5 { // Verify if the reader implements ReadAt and it is not a *minio.Object then we will use parallel uploader. info, err = c.putObjectMultipartStreamFromReadAt(ctx, bucketName, objectName, reader.(io.ReaderAt), size, opts) } else { info, err = c.putObjectMultipartStreamOptionalChecksum(ctx, bucketName, objectName, reader, size, opts) } if err != nil { errResp := ToErrorResponse(err) // Verify if multipart functionality is not available, if not // fall back to single PutObject operation. if errResp.Code == "AccessDenied" && strings.Contains(errResp.Message, "Access Denied") { // Verify if size of reader is greater than '5GiB'. if size > maxSinglePutObjectSize { return UploadInfo{}, errEntityTooLarge(size, maxSinglePutObjectSize, bucketName, objectName) } // Fall back to uploading as single PutObject operation. return c.putObject(ctx, bucketName, objectName, reader, size, opts) } } return info, err } // uploadedPartRes - the response received from a part upload. type uploadedPartRes struct { Error error // Any error encountered while uploading the part. PartNum int // Number of the part uploaded. Size int64 // Size of the part uploaded. Part ObjectPart } type uploadPartReq struct { PartNum int // Number of the part uploaded. Part ObjectPart // Size of the part uploaded. } // putObjectMultipartFromReadAt - Uploads files bigger than 128MiB. // Supports all readers which implements io.ReaderAt interface // (ReadAt method). // // NOTE: This function is meant to be used for all readers which // implement io.ReaderAt which allows us for resuming multipart // uploads but reading at an offset, which would avoid re-read the // data which was already uploaded. Internally this function uses // temporary files for staging all the data, these temporary files are // cleaned automatically when the caller i.e http client closes the // stream after uploading all the contents successfully. func (c *Client) putObjectMultipartStreamFromReadAt(ctx context.Context, bucketName, objectName string, reader io.ReaderAt, size int64, opts PutObjectOptions, ) (info UploadInfo, err error) { // Input validation. if err = s3utils.CheckValidBucketName(bucketName); err != nil { return UploadInfo{}, err } if err = s3utils.CheckValidObjectName(objectName); err != nil { return UploadInfo{}, err } // Calculate the optimal parts info for a given size. totalPartsCount, partSize, lastPartSize, err := OptimalPartInfo(size, opts.PartSize) if err != nil { return UploadInfo{}, err } withChecksum := c.trailingHeaderSupport if withChecksum { if opts.UserMetadata == nil { opts.UserMetadata = make(map[string]string, 1) } opts.UserMetadata["X-Amz-Checksum-Algorithm"] = opts.AutoChecksum.String() } // Initiate a new multipart upload. uploadID, err := c.newUploadID(ctx, bucketName, objectName, opts) if err != nil { return UploadInfo{}, err } delete(opts.UserMetadata, "X-Amz-Checksum-Algorithm") // Aborts the multipart upload in progress, if the // function returns any error, since we do not resume // we should purge the parts which have been uploaded // to relinquish storage space. defer func() { if err != nil { c.abortMultipartUpload(ctx, bucketName, objectName, uploadID) } }() // Total data read and written to server. should be equal to 'size' at the end of the call. var totalUploadedSize int64 // Complete multipart upload. var complMultipartUpload completeMultipartUpload // Declare a channel that sends the next part number to be uploaded. uploadPartsCh := make(chan uploadPartReq) // Declare a channel that sends back the response of a part upload. uploadedPartsCh := make(chan uploadedPartRes) // Used for readability, lastPartNumber is always totalPartsCount. lastPartNumber := totalPartsCount partitionCtx, partitionCancel := context.WithCancel(ctx) defer partitionCancel() // Send each part number to the channel to be processed. go func() { defer close(uploadPartsCh) for p := 1; p <= totalPartsCount; p++ { select { case <-partitionCtx.Done(): return case uploadPartsCh <- uploadPartReq{PartNum: p}: } } }() // Receive each part number from the channel allowing three parallel uploads. for w := 1; w <= opts.getNumThreads(); w++ { go func(partSize int64) { for { var uploadReq uploadPartReq var ok bool select { case <-ctx.Done(): return case uploadReq, ok = <-uploadPartsCh: if !ok { return } // Each worker will draw from the part channel and upload in parallel. } // If partNumber was not uploaded we calculate the missing // part offset and size. For all other part numbers we // calculate offset based on multiples of partSize. readOffset := int64(uploadReq.PartNum-1) * partSize // As a special case if partNumber is lastPartNumber, we // calculate the offset based on the last part size. if uploadReq.PartNum == lastPartNumber { readOffset = size - lastPartSize partSize = lastPartSize } sectionReader := newHook(io.NewSectionReader(reader, readOffset, partSize), opts.Progress) trailer := make(http.Header, 1) if withChecksum { crc := opts.AutoChecksum.Hasher() trailer.Set(opts.AutoChecksum.Key(), base64.StdEncoding.EncodeToString(crc.Sum(nil))) sectionReader = newHashReaderWrapper(sectionReader, crc, func(hash []byte) { trailer.Set(opts.AutoChecksum.Key(), base64.StdEncoding.EncodeToString(hash)) }) } // Proceed to upload the part. p := uploadPartParams{ bucketName: bucketName, objectName: objectName, uploadID: uploadID, reader: sectionReader, partNumber: uploadReq.PartNum, size: partSize, sse: opts.ServerSideEncryption, streamSha256: !opts.DisableContentSha256, sha256Hex: "", trailer: trailer, } objPart, err := c.uploadPart(ctx, p) if err != nil { uploadedPartsCh <- uploadedPartRes{ Error: err, } // Exit the goroutine. return } // Save successfully uploaded part metadata. uploadReq.Part = objPart // Send successful part info through the channel. uploadedPartsCh <- uploadedPartRes{ Size: objPart.Size, PartNum: uploadReq.PartNum, Part: uploadReq.Part, } } }(partSize) } // Gather the responses as they occur and update any // progress bar. for u := 1; u <= totalPartsCount; u++ { select { case <-ctx.Done(): return UploadInfo{}, ctx.Err() case uploadRes := <-uploadedPartsCh: if uploadRes.Error != nil { return UploadInfo{}, uploadRes.Error } // Update the totalUploadedSize. totalUploadedSize += uploadRes.Size complMultipartUpload.Parts = append(complMultipartUpload.Parts, CompletePart{ ETag: uploadRes.Part.ETag, PartNumber: uploadRes.Part.PartNumber, ChecksumCRC32: uploadRes.Part.ChecksumCRC32, ChecksumCRC32C: uploadRes.Part.ChecksumCRC32C, ChecksumSHA1: uploadRes.Part.ChecksumSHA1, ChecksumSHA256: uploadRes.Part.ChecksumSHA256, }) } } // Verify if we uploaded all the data. if totalUploadedSize != size { return UploadInfo{}, errUnexpectedEOF(totalUploadedSize, size, bucketName, objectName) } // Sort all completed parts. sort.Sort(completedParts(complMultipartUpload.Parts)) opts = PutObjectOptions{ ServerSideEncryption: opts.ServerSideEncryption, AutoChecksum: opts.AutoChecksum, } if withChecksum { // Add hash of hashes. crc := opts.AutoChecksum.Hasher() for _, part := range complMultipartUpload.Parts { cs, err := base64.StdEncoding.DecodeString(part.Checksum(opts.AutoChecksum)) if err == nil { crc.Write(cs) } } opts.UserMetadata = map[string]string{opts.AutoChecksum.KeyCapitalized(): base64.StdEncoding.EncodeToString(crc.Sum(nil))} } uploadInfo, err := c.completeMultipartUpload(ctx, bucketName, objectName, uploadID, complMultipartUpload, opts) if err != nil { return UploadInfo{}, err } uploadInfo.Size = totalUploadedSize return uploadInfo, nil } func (c *Client) putObjectMultipartStreamOptionalChecksum(ctx context.Context, bucketName, objectName string, reader io.Reader, size int64, opts PutObjectOptions, ) (info UploadInfo, err error) { // Input validation. if err = s3utils.CheckValidBucketName(bucketName); err != nil { return UploadInfo{}, err } if err = s3utils.CheckValidObjectName(objectName); err != nil { return UploadInfo{}, err } if !opts.SendContentMd5 { if opts.UserMetadata == nil { opts.UserMetadata = make(map[string]string, 1) } opts.UserMetadata["X-Amz-Checksum-Algorithm"] = opts.AutoChecksum.String() } // Calculate the optimal parts info for a given size. totalPartsCount, partSize, lastPartSize, err := OptimalPartInfo(size, opts.PartSize) if err != nil { return UploadInfo{}, err } // Initiates a new multipart request uploadID, err := c.newUploadID(ctx, bucketName, objectName, opts) if err != nil { return UploadInfo{}, err } delete(opts.UserMetadata, "X-Amz-Checksum-Algorithm") // Aborts the multipart upload if the function returns // any error, since we do not resume we should purge // the parts which have been uploaded to relinquish // storage space. defer func() { if err != nil { c.abortMultipartUpload(ctx, bucketName, objectName, uploadID) } }() // Create checksums // CRC32C is ~50% faster on AMD64 @ 30GB/s var crcBytes []byte customHeader := make(http.Header) crc := opts.AutoChecksum.Hasher() md5Hash := c.md5Hasher() defer md5Hash.Close() // Total data read and written to server. should be equal to 'size' at the end of the call. var totalUploadedSize int64 // Initialize parts uploaded map. partsInfo := make(map[int]ObjectPart) // Create a buffer. buf := make([]byte, partSize) // Avoid declaring variables in the for loop var md5Base64 string // Part number always starts with '1'. var partNumber int for partNumber = 1; partNumber <= totalPartsCount; partNumber++ { // Proceed to upload the part. if partNumber == totalPartsCount { partSize = lastPartSize } length, rerr := readFull(reader, buf) if rerr == io.EOF && partNumber > 1 { break } if rerr != nil && rerr != io.ErrUnexpectedEOF && err != io.EOF { return UploadInfo{}, rerr } // Calculate md5sum. if opts.SendContentMd5 { md5Hash.Reset() md5Hash.Write(buf[:length]) md5Base64 = base64.StdEncoding.EncodeToString(md5Hash.Sum(nil)) } else { // Add CRC32C instead. crc.Reset() crc.Write(buf[:length]) cSum := crc.Sum(nil) customHeader.Set(opts.AutoChecksum.KeyCapitalized(), base64.StdEncoding.EncodeToString(cSum)) crcBytes = append(crcBytes, cSum...) } // Update progress reader appropriately to the latest offset // as we read from the source. hooked := newHook(bytes.NewReader(buf[:length]), opts.Progress) p := uploadPartParams{bucketName: bucketName, objectName: objectName, uploadID: uploadID, reader: hooked, partNumber: partNumber, md5Base64: md5Base64, size: partSize, sse: opts.ServerSideEncryption, streamSha256: !opts.DisableContentSha256, customHeader: customHeader} objPart, uerr := c.uploadPart(ctx, p) if uerr != nil { return UploadInfo{}, uerr } // Save successfully uploaded part metadata. partsInfo[partNumber] = objPart // Save successfully uploaded size. totalUploadedSize += partSize } // Verify if we uploaded all the data. if size > 0 { if totalUploadedSize != size { return UploadInfo{}, errUnexpectedEOF(totalUploadedSize, size, bucketName, objectName) } } // Complete multipart upload. var complMultipartUpload completeMultipartUpload // Loop over total uploaded parts to save them in // Parts array before completing the multipart request. for i := 1; i < partNumber; i++ { part, ok := partsInfo[i] if !ok { return UploadInfo{}, errInvalidArgument(fmt.Sprintf("Missing part number %d", i)) } complMultipartUpload.Parts = append(complMultipartUpload.Parts, CompletePart{ ETag: part.ETag, PartNumber: part.PartNumber, ChecksumCRC32: part.ChecksumCRC32, ChecksumCRC32C: part.ChecksumCRC32C, ChecksumSHA1: part.ChecksumSHA1, ChecksumSHA256: part.ChecksumSHA256, }) } // Sort all completed parts. sort.Sort(completedParts(complMultipartUpload.Parts)) opts = PutObjectOptions{ ServerSideEncryption: opts.ServerSideEncryption, AutoChecksum: opts.AutoChecksum, } if len(crcBytes) > 0 { // Add hash of hashes. crc.Reset() crc.Write(crcBytes) opts.UserMetadata = map[string]string{opts.AutoChecksum.KeyCapitalized(): base64.StdEncoding.EncodeToString(crc.Sum(nil))} } uploadInfo, err := c.completeMultipartUpload(ctx, bucketName, objectName, uploadID, complMultipartUpload, opts) if err != nil { return UploadInfo{}, err } uploadInfo.Size = totalUploadedSize return uploadInfo, nil } // putObjectMultipartStreamParallel uploads opts.NumThreads parts in parallel. // This is expected to take opts.PartSize * opts.NumThreads * (GOGC / 100) bytes of buffer. func (c *Client) putObjectMultipartStreamParallel(ctx context.Context, bucketName, objectName string, reader io.Reader, opts PutObjectOptions, ) (info UploadInfo, err error) { // Input validation. if err = s3utils.CheckValidBucketName(bucketName); err != nil { return UploadInfo{}, err } if err = s3utils.CheckValidObjectName(objectName); err != nil { return UploadInfo{}, err } if !opts.SendContentMd5 { if opts.UserMetadata == nil { opts.UserMetadata = make(map[string]string, 1) } opts.UserMetadata["X-Amz-Checksum-Algorithm"] = opts.AutoChecksum.String() } // Cancel all when an error occurs. ctx, cancel := context.WithCancel(ctx) defer cancel() // Calculate the optimal parts info for a given size. totalPartsCount, partSize, _, err := OptimalPartInfo(-1, opts.PartSize) if err != nil { return UploadInfo{}, err } // Initiates a new multipart request uploadID, err := c.newUploadID(ctx, bucketName, objectName, opts) if err != nil { return UploadInfo{}, err } delete(opts.UserMetadata, "X-Amz-Checksum-Algorithm") // Aborts the multipart upload if the function returns // any error, since we do not resume we should purge // the parts which have been uploaded to relinquish // storage space. defer func() { if err != nil { c.abortMultipartUpload(ctx, bucketName, objectName, uploadID) } }() // Create checksums // CRC32C is ~50% faster on AMD64 @ 30GB/s var crcBytes []byte crc := opts.AutoChecksum.Hasher() // Total data read and written to server. should be equal to 'size' at the end of the call. var totalUploadedSize int64 // Initialize parts uploaded map. partsInfo := make(map[int]ObjectPart) // Create a buffer. nBuffers := int64(opts.NumThreads) bufs := make(chan []byte, nBuffers) all := make([]byte, nBuffers*partSize) for i := int64(0); i < nBuffers; i++ { bufs <- all[i*partSize : i*partSize+partSize] } var wg sync.WaitGroup var mu sync.Mutex errCh := make(chan error, opts.NumThreads) reader = newHook(reader, opts.Progress) // Part number always starts with '1'. var partNumber int for partNumber = 1; partNumber <= totalPartsCount; partNumber++ { // Proceed to upload the part. var buf []byte select { case buf = <-bufs: case err = <-errCh: cancel() wg.Wait() return UploadInfo{}, err } if int64(len(buf)) != partSize { return UploadInfo{}, fmt.Errorf("read buffer < %d than expected partSize: %d", len(buf), partSize) } length, rerr := readFull(reader, buf) if rerr == io.EOF && partNumber > 1 { // Done break } if rerr != nil && rerr != io.ErrUnexpectedEOF && err != io.EOF { cancel() wg.Wait() return UploadInfo{}, rerr } // Calculate md5sum. customHeader := make(http.Header) if !opts.SendContentMd5 { // Add CRC32C instead. crc.Reset() crc.Write(buf[:length]) cSum := crc.Sum(nil) customHeader.Set(opts.AutoChecksum.Key(), base64.StdEncoding.EncodeToString(cSum)) crcBytes = append(crcBytes, cSum...) } wg.Add(1) go func(partNumber int) { // Avoid declaring variables in the for loop var md5Base64 string if opts.SendContentMd5 { md5Hash := c.md5Hasher() md5Hash.Write(buf[:length]) md5Base64 = base64.StdEncoding.EncodeToString(md5Hash.Sum(nil)) md5Hash.Close() } defer wg.Done() p := uploadPartParams{ bucketName: bucketName, objectName: objectName, uploadID: uploadID, reader: bytes.NewReader(buf[:length]), partNumber: partNumber, md5Base64: md5Base64, size: int64(length), sse: opts.ServerSideEncryption, streamSha256: !opts.DisableContentSha256, customHeader: customHeader, } objPart, uerr := c.uploadPart(ctx, p) if uerr != nil { errCh <- uerr return } // Save successfully uploaded part metadata. mu.Lock() partsInfo[partNumber] = objPart mu.Unlock() // Send buffer back so it can be reused. bufs <- buf }(partNumber) // Save successfully uploaded size. totalUploadedSize += int64(length) } wg.Wait() // Collect any error select { case err = <-errCh: return UploadInfo{}, err default: } // Complete multipart upload. var complMultipartUpload completeMultipartUpload // Loop over total uploaded parts to save them in // Parts array before completing the multipart request. for i := 1; i < partNumber; i++ { part, ok := partsInfo[i] if !ok { return UploadInfo{}, errInvalidArgument(fmt.Sprintf("Missing part number %d", i)) } complMultipartUpload.Parts = append(complMultipartUpload.Parts, CompletePart{ ETag: part.ETag, PartNumber: part.PartNumber, ChecksumCRC32: part.ChecksumCRC32, ChecksumCRC32C: part.ChecksumCRC32C, ChecksumSHA1: part.ChecksumSHA1, ChecksumSHA256: part.ChecksumSHA256, }) } // Sort all completed parts. sort.Sort(completedParts(complMultipartUpload.Parts)) opts = PutObjectOptions{ ServerSideEncryption: opts.ServerSideEncryption, AutoChecksum: opts.AutoChecksum, } if len(crcBytes) > 0 { // Add hash of hashes. crc.Reset() crc.Write(crcBytes) opts.UserMetadata = map[string]string{opts.AutoChecksum.KeyCapitalized(): base64.StdEncoding.EncodeToString(crc.Sum(nil))} } uploadInfo, err := c.completeMultipartUpload(ctx, bucketName, objectName, uploadID, complMultipartUpload, opts) if err != nil { return UploadInfo{}, err } uploadInfo.Size = totalUploadedSize return uploadInfo, nil } // putObject special function used Google Cloud Storage. This special function // is used for Google Cloud Storage since Google's multipart API is not S3 compatible. func (c *Client) putObject(ctx context.Context, bucketName, objectName string, reader io.Reader, size int64, opts PutObjectOptions) (info UploadInfo, err error) { // Input validation. if err := s3utils.CheckValidBucketName(bucketName); err != nil { return UploadInfo{}, err } if err := s3utils.CheckValidObjectName(objectName); err != nil { return UploadInfo{}, err } // Size -1 is only supported on Google Cloud Storage, we error // out in all other situations. if size < 0 && !s3utils.IsGoogleEndpoint(*c.endpointURL) { return UploadInfo{}, errEntityTooSmall(size, bucketName, objectName) } if opts.SendContentMd5 && s3utils.IsGoogleEndpoint(*c.endpointURL) && size < 0 { return UploadInfo{}, errInvalidArgument("MD5Sum cannot be calculated with size '-1'") } var readSeeker io.Seeker if size > 0 { if isReadAt(reader) && !isObject(reader) { seeker, ok := reader.(io.Seeker) if ok { offset, err := seeker.Seek(0, io.SeekCurrent) if err != nil { return UploadInfo{}, errInvalidArgument(err.Error()) } reader = io.NewSectionReader(reader.(io.ReaderAt), offset, size) readSeeker = reader.(io.Seeker) } } } var md5Base64 string if opts.SendContentMd5 { // Calculate md5sum. hash := c.md5Hasher() if readSeeker != nil { if _, err := io.Copy(hash, reader); err != nil { return UploadInfo{}, err } // Seek back to beginning of io.NewSectionReader's offset. _, err = readSeeker.Seek(0, io.SeekStart) if err != nil { return UploadInfo{}, errInvalidArgument(err.Error()) } } else { // Create a buffer. buf := make([]byte, size) length, err := readFull(reader, buf) if err != nil && err != io.ErrUnexpectedEOF && err != io.EOF { return UploadInfo{}, err } hash.Write(buf[:length]) reader = bytes.NewReader(buf[:length]) } md5Base64 = base64.StdEncoding.EncodeToString(hash.Sum(nil)) hash.Close() } // Update progress reader appropriately to the latest offset as we // read from the source. progressReader := newHook(reader, opts.Progress) // This function does not calculate sha256 and md5sum for payload. // Execute put object. return c.putObjectDo(ctx, bucketName, objectName, progressReader, md5Base64, "", size, opts) } // putObjectDo - executes the put object http operation. // NOTE: You must have WRITE permissions on a bucket to add an object to it. func (c *Client) putObjectDo(ctx context.Context, bucketName, objectName string, reader io.Reader, md5Base64, sha256Hex string, size int64, opts PutObjectOptions) (UploadInfo, error) { // Input validation. if err := s3utils.CheckValidBucketName(bucketName); err != nil { return UploadInfo{}, err } if err := s3utils.CheckValidObjectName(objectName); err != nil { return UploadInfo{}, err } // Set headers. customHeader := opts.Header() // Add CRC when client supports it, MD5 is not set, not Google and we don't add SHA256 to chunks. addCrc := c.trailingHeaderSupport && md5Base64 == "" && !s3utils.IsGoogleEndpoint(*c.endpointURL) && (opts.DisableContentSha256 || c.secure) if addCrc { // If user has added checksums, don't add them ourselves. for k := range opts.UserMetadata { if strings.HasPrefix(strings.ToLower(k), "x-amz-checksum-") { addCrc = false } } } // Populate request metadata. reqMetadata := requestMetadata{ bucketName: bucketName, objectName: objectName, customHeader: customHeader, contentBody: reader, contentLength: size, contentMD5Base64: md5Base64, contentSHA256Hex: sha256Hex, streamSha256: !opts.DisableContentSha256, } if addCrc { opts.AutoChecksum.SetDefault(ChecksumCRC32C) reqMetadata.addCrc = &opts.AutoChecksum } if opts.Internal.SourceVersionID != "" { if opts.Internal.SourceVersionID != nullVersionID { if _, err := uuid.Parse(opts.Internal.SourceVersionID); err != nil { return UploadInfo{}, errInvalidArgument(err.Error()) } } urlValues := make(url.Values) urlValues.Set("versionId", opts.Internal.SourceVersionID) reqMetadata.queryValues = urlValues } // Execute PUT an objectName. resp, err := c.executeMethod(ctx, http.MethodPut, reqMetadata) defer closeResponse(resp) if err != nil { return UploadInfo{}, err } if resp != nil { if resp.StatusCode != http.StatusOK { return UploadInfo{}, httpRespToErrorResponse(resp, bucketName, objectName) } } // extract lifecycle expiry date and rule ID expTime, ruleID := amzExpirationToExpiryDateRuleID(resp.Header.Get(amzExpiration)) h := resp.Header return UploadInfo{ Bucket: bucketName, Key: objectName, ETag: trimEtag(h.Get("ETag")), VersionID: h.Get(amzVersionID), Size: size, Expiration: expTime, ExpirationRuleID: ruleID, // Checksum values ChecksumCRC32: h.Get("x-amz-checksum-crc32"), ChecksumCRC32C: h.Get("x-amz-checksum-crc32c"), ChecksumSHA1: h.Get("x-amz-checksum-sha1"), ChecksumSHA256: h.Get("x-amz-checksum-sha256"), }, nil }