读取的数据长度与预期不同：dataLength=964481363；预期长度=964481376；

Question

我正在尝试从 S3 读取加密对象，然后使用不同的加密密钥将其上传到 S3 中的新存储桶。当我尝试读取对象时，使用 getObject() 并尝试使用 PutObject 请求放置对象。

当我打印源的内容长度时，是964481376。那么，数据长度是从哪里来的呢？即 964481363

我的源文件的元数据如下所示：

内容类型

二进制/八位字节流

x-amz-meta-x-amz-unencrypted-content-length

964481363

x-amz-meta-x-amz-wrap-alg

公里

我无法共享 KMS 密钥。

public boolean copyS3Object(AmazonS3Encryption sourceS3Client, AmazonS3URI sourceS3Uri,
            AmazonS3Encryption destS3Client, AmazonS3URI destS3Uri) throws AmazonServiceException, IOException {
        //String eTag;
        S3Object sourceS3Object = null;

        try {
            //Get the Source object stream
            sourceS3Object = sourceS3Client.getObject(sourceS3Uri.getBucket(), sourceS3Uri.getKey());
            ObjectMetadata objectMetadata = sourceS3Object.getObjectMetadata();
            System.out.println("content length " + objectMetadata.getContentLength());
            PutObjectRequest putRequest = new PutObjectRequest(destS3Uri.getBucket(), destS3Uri.getKey(),
                    sourceS3Object.getObjectContent(), sourceS3Object.getObjectMetadata());

            destS3Client.putObject(putRequest);
//
//            if (eTag.isEmpty()) {
//                System.out.println("Copy failed, New object in " + destS3Uri.toString() + " is empty");
//                return false;
//            }

        } catch (AmazonServiceException e) {
            throw e;
        } finally {
            if (sourceS3Object != null) {
                sourceS3Object.close();
            }
        }
        //System.out.println("Copied successfully to " + destS3Uri.toString() + " Etag:" + eTag);
        return true;
    }

但我收到以下错误：

{ "errorMessage": "读取的数据长度与预期不同：dataLength=964481363；expectedLength=964481376；includeSkipped=false；in.getClass()=class com.amazonaws.internal.ReleasableInputStream；markedSupported=false；marked=0； resetSinceLastMarked=false；markCount=0；resetCount=0", “errorType”：“com.amazonaws.SdkClientException”， “堆栈跟踪”： [ “com.amazonaws.util.LengthCheckInputStream.checkLength（LengthCheckInputStream.java:151）”， “com.amazonaws.util.LengthCheckInputStream.read（LengthCheckInputStream.java:109）”， "java.io.FilterInputStream.read(FilterInputStream.java:107)", “com.amazonaws.services.s3.internal.crypto.CipherLiteInputStream.nextChunk（CipherLiteInputStream.java:225）”， “com.amazonaws.services.s3.internal.crypto.CipherLiteInputStream.read（CipherLiteInputStream.java:118）”， “com.amazonaws.services.s3.internal.crypto.RenewableCipherLiteInputStream.read（RenewableCipherLiteInputStream.java:112）”， “com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:90)”, “com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:90)”, “com.amazonaws.util.LengthCheckInputStream.read（LengthCheckInputStream.java:107）”， “com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:90)”, “com.amazonaws.services.s3.internal.MD5DigestCalculatingInputStream.read（MD5DigestCalculatingInputStream.java:128）”， "java.io.BufferedInputStream.fill(BufferedInputStream.java:246)", "java.io.BufferedInputStream.read1(BufferedInputStream.java:286)", "java.io.BufferedInputStream.read(BufferedInputStream.java:345)", “com.amazonaws.internal.SdkBufferedInputStream.read(SdkBufferedInputStream.java:76)”, “com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:90)”, “com.amazonaws.event.ProgressInputStream.read(ProgressInputStream.java:180)”, “com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:90)”, “org.apache.http.entity.InputStreamEntity.writeTo(InputStreamEntity.java:140)”, “com.amazonaws.http.RepeatableInputStreamRequestEntity.writeTo(RepeatableInputStreamRequestEntity.java:160)”, “org.apache.http.impl.DefaultBHttpClientConnection.sendRequestEntity（DefaultBHttpClientConnection.java:156）”， “org.apache.http.impl.conn.CPoolProxy.sendRequestEntity(CPoolProxy.java:162)”, “org.apache.http.protocol.HttpRequestExecutor.doSendRequest(HttpRequestExecutor.java:238)”, “com.amazonaws.http.protocol.SdkHttpRequestExecutor.doSendRequest(SdkHttpRequestExecutor.java:63)”, “org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:123)”, “org.apache.http.impl.execchain.MainClientExec.execute（MainClientExec.java:271）”， “org.apache.http.impl.execchain.ProtocolExec.execute（ProtocolExec.java:184）”， “org.apache.http.impl.client.InternalHttpClient.doExecute(InternalHttpClient.java:184)”, “org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:82)”, “org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:55)”, “com.amazonaws.http.apache.client.impl.SdkHttpClient.execute(SdkHttpClient.java:72)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeOneRequest(AmazonHttpClient.java:1297)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeHelper(AmazonHttpClient.java:1113)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.doExecute(AmazonHttpClient.java:770)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.executeWithTimer(AmazonHttpClient.java:744)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.execute(AmazonHttpClient.java:726)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutor.access$500(AmazonHttpClient.java:686)”, “com.amazonaws.http.AmazonHttpClient$RequestExecutionBuilderImpl.execute(AmazonHttpClient.java:668)”, “com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:532)”, “com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:512)”, “com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:4914)”, “com.amazonaws.services.s3.AmazonS3Client.invoke(AmazonS3Client.java:4860)”, “com.amazonaws.services.s3.AmazonS3Client.access$300(AmazonS3Client.java:389)”, “com.amazonaws.services.s3.AmazonS3Client$PutObjectStrategy.invokeServiceCall(AmazonS3Client.java:5793)”, “com.amazonaws.services.s3.AmazonS3Client.uploadObject(AmazonS3Client.java:1786)”, “com.amazonaws.services.s3.AmazonS3Client.putObject(AmazonS3Client.java:1746)”, “com.amazonaws.services.s3.AmazonS3EncryptionClient.access$101(AmazonS3EncryptionClient.java:81)”, “com.amazonaws.services.s3.AmazonS3EncryptionClient$S3DirectImpl.putObject(AmazonS3EncryptionClient.java:690)”, “com.amazonaws.services.s3.internal.crypto.S3CryptoModuleBase.putObjectUsingMetadata（S3CryptoModuleBase.java:175）”， “com.amazonaws.services.s3.internal.crypto.S3CryptoModuleBase.putObjectSecurely（S3CryptoModuleBase.java:161）”， “com.amazonaws.services.s3.internal.crypto.CryptoModuleDispatcher.putObjectSecurely（CryptoModuleDispatcher.java:108）”， “com.amazonaws.services.s3.AmazonS3EncryptionClient.putObject(AmazonS3EncryptionClient.java:570)”, “com.amazon.testCase.lambda.object.UploadObject.coyS3Object（UploadObject.java:93）”， “com.amazon.testCase.lambda.object.UploadObject.handleRequest(UploadObject.java:54)”, "sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)", “sun.reflect.NativeMethodAccessorImpl.invoke（NativeMethodAccessorImpl.java:62）”， “sun.reflect.DelegatingMethodAccessorImpl.invoke（DelegatingMethodAccessorImpl.java:43）”， “java.lang.reflect.Method.invoke(Method.java:498)” ] }

Answer 1

我发现了问题所在。 S3 对象的内容长度是加密后的数据长度。但是当我放置对象时，我试图放置未加密的数据。 所以我需要将对象的内容长度显式设置为未加密的长度。下面的代码解决了这个问题。

 try {
            //Get the Source object stream
            sourceS3Object = sourceS3Client.getObject(sourceS3Uri.getBucket(), sourceS3Uri.getKey());
            //For a decrypted object, the content length in metadata has the encrypted length
            //Set the content length to the unencrypted-data-length
            ObjectMetadata objectMetadata = sourceS3Object.getObjectMetadata();
            Map<String, String> modelMetaData = objectMetadata.getUserMetadata();
            Long unencryptedDataLength = Long.parseLong(modelMetaData.get(
                    "x-amz-unencrypted-content-length"));
            objectMetadata.setContentLength(unencryptedDataLength);
            PutObjectRequest putRequest = new PutObjectRequest(destS3Uri.getBucket(), destS3Uri.getKey(),
                    sourceS3Object.getObjectContent(), objectMetadata);

            eTag = destS3Client.putObject(putRequest).getETag();

            if (eTag.isEmpty()) {
                System.out.println("Copy failed, New object in " + destS3Uri.toString() + " is empty");
                return false;
            }