software.amazon.awssdk.http.auth.aws.internal.signer.Checksummer Maven / Gradle / Ivy
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/*
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file 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 software.amazon.awssdk.http.auth.aws.internal.signer;
import static software.amazon.awssdk.checksums.DefaultChecksumAlgorithm.SHA256;
import static software.amazon.awssdk.http.auth.aws.internal.signer.FlexibleChecksummer.option;
import static software.amazon.awssdk.http.auth.aws.internal.signer.util.ChecksumUtil.ConstantChecksumAlgorithm;
import static software.amazon.awssdk.http.auth.aws.internal.signer.util.ChecksumUtil.checksumHeaderName;
import static software.amazon.awssdk.http.auth.aws.internal.signer.util.SignerConstant.X_AMZ_CONTENT_SHA256;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.util.concurrent.CompletableFuture;
import org.reactivestreams.Publisher;
import software.amazon.awssdk.annotations.SdkInternalApi;
import software.amazon.awssdk.checksums.spi.ChecksumAlgorithm;
import software.amazon.awssdk.http.ContentStreamProvider;
import software.amazon.awssdk.http.SdkHttpRequest;
import software.amazon.awssdk.utils.BinaryUtils;
/**
* An interface for defining how a checksum is formed from a payload synchronously and asynchronously.
*
* The implementation may choose to also manipulate the request with the checksum, such as adding it as a header.
*
* Note: Currently, checksummers set the X_AMZ_CONTENT_SHA256 header for all requests. It is not strictly
* required to add the headers to all AWS requests - it's required for S3 and a couple of other select use cases. The
* pre-SRA implementation has a stricter set of rules for when to add the header. Being more restrictive with adding
* the header would require restructuring the signer / checksummer design.
*/
@SdkInternalApi
public interface Checksummer {
/**
* Get a default implementation of a checksummer, which calculates the SHA-256 checksum and places it in the
* x-amz-content-sha256 header.
*/
static Checksummer create() {
return new FlexibleChecksummer(
option().headerName(X_AMZ_CONTENT_SHA256).algorithm(SHA256).formatter(BinaryUtils::toHex).build()
);
}
/**
* Get a flexible checksummer that performs two checksums: the given checksum-algorithm and the SHA-256 checksum. It places
* the SHA-256 checksum in x-amz-content-sha256 header, and the given checksum-algorithm in the x-amz-checksum-[name] header.
*/
static Checksummer forFlexibleChecksum(ChecksumAlgorithm checksumAlgorithm) {
if (checksumAlgorithm != null) {
return new FlexibleChecksummer(
option().headerName(X_AMZ_CONTENT_SHA256).algorithm(SHA256).formatter(BinaryUtils::toHex)
.build(),
option().headerName(checksumHeaderName(checksumAlgorithm)).algorithm(checksumAlgorithm)
.formatter(BinaryUtils::toBase64).build()
);
}
throw new IllegalArgumentException("Checksum Algorithm cannot be null!");
}
/**
* Get a precomputed checksummer which places the precomputed checksum to the x-amz-content-sha256 header.
*/
static Checksummer forPrecomputed256Checksum(String precomputedSha256) {
return new PrecomputedSha256Checksummer(() -> precomputedSha256);
}
/**
* Get a flexible checksummer that performs two checksums: the given checksum-algorithm and a precomputed checksum from the
* given checksum string. It places the precomputed checksum in x-amz-content-sha256 header, and the given checksum-algorithm
* in the x-amz-checksum-[name] header.
*/
static Checksummer forFlexibleChecksum(String precomputedSha256, ChecksumAlgorithm checksumAlgorithm) {
if (checksumAlgorithm != null) {
return new FlexibleChecksummer(
option().headerName(X_AMZ_CONTENT_SHA256).algorithm(new ConstantChecksumAlgorithm(precomputedSha256))
.formatter(b -> new String(b, StandardCharsets.UTF_8)).build(),
option().headerName(checksumHeaderName(checksumAlgorithm)).algorithm(checksumAlgorithm)
.formatter(BinaryUtils::toBase64).build()
);
}
throw new IllegalArgumentException("Checksum Algorithm cannot be null!");
}
static Checksummer forNoOp() {
return new FlexibleChecksummer();
}
/**
* Given a payload, calculate a checksum and add it to the request.
*/
void checksum(ContentStreamProvider payload, SdkHttpRequest.Builder request);
/**
* Given a payload, asynchronously calculate a checksum and promise to add it to the request.
*/
CompletableFuture> checksum(Publisher payload, SdkHttpRequest.Builder request);
}