Do not sign Transfer-Encoding Header if present on the request

.changes/next-release/bugfix-AWSSDKforJavav2-ed80b40.json

@@ -0,0 +1,6 @@
+{
+    "type": "bugfix",
+    "category": "AWS SDK for Java v2",
+    "contributor": "",
+    "description": "Transfer-Encoding headers will no longer be signed during SigV4 authentication"
+}

core/auth/src/main/java/software/amazon/awssdk/auth/signer/internal/AbstractAws4Signer.java

@@ -68,7 +68,7 @@ public abstract class AbstractAws4Signer<T extends Aws4SignerParams, U extends A
     private static final FifoCache<SignerKey> SIGNER_CACHE =
         new FifoCache<>(SIGNER_CACHE_MAX_SIZE);
     private static final List<String> LIST_OF_HEADERS_TO_IGNORE_IN_LOWER_CASE =
-        Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect");
+        Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect", "transfer-encoding");
 
     protected SdkHttpFullRequest.Builder doSign(SdkHttpFullRequest request,
                                                 Aws4SignerRequestParams requestParams,

core/auth/src/main/java/software/amazon/awssdk/auth/signer/internal/util/HeaderTransformsHelper.java

@@ -32,7 +32,7 @@
 public final class HeaderTransformsHelper {
 
     private static final List<String> LIST_OF_HEADERS_TO_IGNORE_IN_LOWER_CASE =
-            Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect");
+        Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect", "transfer-encoding");
 
     private HeaderTransformsHelper() {
     }

core/auth/src/test/java/software/amazon/awssdk/auth/signer/Aws4SignerTest.java

@@ -398,4 +398,18 @@ public void signing_with_Crc32Checksum_with__trailer_header_already_present() th
         assertThat(signed.firstMatchingHeader(SignerConstant.X_AMZ_CONTENT_SHA256)).isNotPresent();
         assertThat(signed.firstMatchingHeader("Authorization")).hasValue(expectedAuthorization);
     }
+
+    @Test
+    public void TransferEncodingIsNotSigned_NotSigned() {
+        AwsBasicCredentials credentials = AwsBasicCredentials.create("akid", "skid");
+        SdkHttpFullRequest.Builder request = generateBasicRequest();
+        request.putHeader("Transfer-Encoding", "chunked");
+
+        SdkHttpFullRequest actual = SignerTestUtils.signRequest(signer, request.build(), credentials, "demo", signingOverrideClock, "us-east-1");
+
+        assertThat(actual.firstMatchingHeader("Authorization"))
+            .hasValue("AWS4-HMAC-SHA256 Credential=akid/19810216/us-east-1/demo/aws4_request, " +
+                      "SignedHeaders=host;x-amz-archive-description;x-amz-date, " +
+                      "Signature=581d0042389009a28d461124138f1fe8eeb8daed87611d2a2b47fd3d68d81d73");
+    }
 }

core/auth/src/test/java/software/amazon/awssdk/auth/signer/internal/util/HeaderTransformsHelperTest.java

@@ -0,0 +1,61 @@
+/*
+ * 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.auth.signer.internal.util;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class HeaderTransformsHelperTest {
+
+    @Test
+    void shouldExcludeIgnoredHeadersWhenCanonicalizing() {
+        Map<String, List<String>> headers = new HashMap<>();
+
+        // Ignored headers that should be excluded from signing
+        headers.put("connection", Collections.singletonList("keep-alive"));
+        headers.put("x-amzn-trace-id", Collections.singletonList("Root=1-234567890"));
+        headers.put("user-agent", Collections.singletonList("md/user"));
+        headers.put("expect", Collections.singletonList("100-continue"));
+        headers.put("transfer-encoding", Collections.singletonList("chunked"));
+
+        // Headers that should be included in signing
+        headers.put("Content-Type", Collections.singletonList("application/json"));
+        headers.put("Host", Collections.singletonList("example.com"));
+
+        Map<String, List<String>> canonicalizedHeaders = HeaderTransformsHelper.canonicalizeSigningHeaders(headers);
+
+        assertEquals(2, canonicalizedHeaders.size(), "Should only contain non-ignored headers");
+
+        // Verify included headers
+        assertTrue(canonicalizedHeaders.containsKey("content-type"), "Should contain content-type header");
+        assertTrue(canonicalizedHeaders.containsKey("host"), "Should contain host header");
+
+        // Verify excluded headers
+        assertFalse(canonicalizedHeaders.containsKey("connection"), "Should not contain connection header");
+        assertFalse(canonicalizedHeaders.containsKey("x-amzn-trace-id"), "Should not contain x-amzn-trace-id header");
+        assertFalse(canonicalizedHeaders.containsKey("user-agent"), "Should not contain user-agent header");
+        assertFalse(canonicalizedHeaders.containsKey("expect"), "Should not contain expect header");
+        assertFalse(canonicalizedHeaders.containsKey("transfer-encoding"), "Should not contain transfer-encoding header");
+    }
+
+}

core/http-auth-aws/src/main/java/software/amazon/awssdk/http/auth/aws/internal/signer/V4CanonicalRequest.java

@@ -43,7 +43,7 @@
 @Immutable
 public final class V4CanonicalRequest {
     private static final List<String> HEADERS_TO_IGNORE_IN_LOWER_CASE =
-        Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect");
+        Arrays.asList("connection", "x-amzn-trace-id", "user-agent", "expect", "transfer-encoding");
 
     private final SdkHttpRequest request;
     private final String contentHash;

core/http-auth-aws/src/test/java/software/amazon/awssdk/http/auth/aws/internal/signer/V4CanonicalRequestTest.java

@@ -84,6 +84,7 @@ public void canonicalRequest_WithForbiddenHeaders_shouldExcludeForbidden() {
                                                .method(SdkHttpMethod.PUT)
                                                .putHeader("foo", "bar")
                                                .putHeader("x-amzn-trace-id", "wontBePresent")
+                                               .putHeader("Transfer-Encoding", "wontBePresent")
                                                .build();
         V4CanonicalRequest cr = new V4CanonicalRequest(request, "sha-256",
                                                        new V4CanonicalRequest.Options(true,

test/codegen-generated-classes-test/src/test/java/software/amazon/awssdk/services/AsyncRequestCompressionTest.java

@@ -26,7 +26,8 @@
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.reactivestreams.Subscriber;
-import software.amazon.awssdk.auth.credentials.AnonymousCredentialsProvider;
+import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
+import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
 import software.amazon.awssdk.core.SdkBytes;
 import software.amazon.awssdk.core.async.AsyncRequestBody;
 import software.amazon.awssdk.core.async.AsyncResponseTransformer;
@@ -44,17 +45,19 @@
 public class AsyncRequestCompressionTest {
     private static final String UNCOMPRESSED_BODY =
         "RequestCompressionTest-RequestCompressionTest-RequestCompressionTest-RequestCompressionTest-RequestCompressionTest";
+    private  static String TRANSFER_ENCODING_HEADER = "Transfer-Encoding";
     private String compressedBody;
     private int compressedLen;
     private MockAsyncHttpClient mockAsyncHttpClient;
     private ProtocolRestJsonAsyncClient asyncClient;
     private Compressor compressor;
+    private static final AwsBasicCredentials CLIENT_CREDENTIALS = AwsBasicCredentials.create("akid", "skid");
 
     @BeforeEach
     public void setUp() {
         mockAsyncHttpClient = new MockAsyncHttpClient();
         asyncClient = ProtocolRestJsonAsyncClient.builder()
-                                                 .credentialsProvider(AnonymousCredentialsProvider.create())
+                                                 .credentialsProvider(StaticCredentialsProvider.create(CLIENT_CREDENTIALS))
                                                  .region(Region.US_EAST_1)
                                                  .httpClient(mockAsyncHttpClient)
                                                  .build();
@@ -129,7 +132,9 @@ public void asyncStreamingOperation_compressionEnabled_compressesCorrectly() {
         assertThat(loggedBody).isEqualTo(compressedBody);
         assertThat(loggedRequest.firstMatchingHeader("Content-encoding").get()).isEqualTo("gzip");
         assertThat(loggedRequest.matchingHeaders("Content-Length")).isEmpty();
-        assertThat(loggedRequest.firstMatchingHeader("Transfer-Encoding").get()).isEqualTo("chunked");
+        assertThat(loggedRequest.firstMatchingHeader(TRANSFER_ENCODING_HEADER).get()).isEqualTo("chunked");
+        assertThat(loggedRequest.firstMatchingHeader("Authorization").get())
+            .doesNotContainIgnoringCase(TRANSFER_ENCODING_HEADER);
     }
 
     @Test
@@ -172,8 +177,8 @@ public void asyncStreamingOperation_compressionEnabledWithRetry_compressesCorrec
 
         assertThat(loggedBody).isEqualTo(compressedBody);
         assertThat(loggedRequest.firstMatchingHeader("Content-encoding").get()).isEqualTo("gzip");
-        assertThat(loggedRequest.matchingHeaders("Content-Length")).isEmpty();
-        assertThat(loggedRequest.firstMatchingHeader("Transfer-Encoding").get()).isEqualTo("chunked");
+        assertThat(loggedRequest.matchingHeaders("Content-Length")).isEmpty();assertThat(loggedRequest.firstMatchingHeader(TRANSFER_ENCODING_HEADER).get()).isEqualTo("chunked");
+        assertThat(loggedRequest.firstMatchingHeader("Authorization").get()).doesNotContainIgnoringCase(TRANSFER_ENCODING_HEADER);
     }
 
     private HttpExecuteResponse mockResponse() {