0

Disable RendererSideContentDecoding for navigations

The RendererSideContentDecoding feature allows the network service to
skip decoding response bodies (e.g., handling `Content-Encoding: gzip`),
delegating this task to the client, typically the renderer process. This
is activated by setting the `client_side_content_decoding_enabled` flag
on the `ResourceRequest`.

However, enabling this feature for navigation requests caused issues.
Not all navigation responses are sent to a renderer process. For
instance, a response with a `Content-Disposition: attachment` header
triggers a download. If the network service skips decoding for such a
response, the user would incorrectly download the raw, encoded file
(e.g., the gzipped data) instead of the decoded content.

Determining within the network service whether a navigation response
will ultimately lead to a download is complex (See
`content::download_utils::MustDownload()` method). Therefore, this CL
takes a simpler, more robust approach: it disables the
`RendererSideContentDecoding` feature entirely for navigation requests.
This is achieved by removing the logic that sets the
`client_side_content_decoding_enabled` flag within
`CreateResourceRequestForNavigation`.

As a result, the network service will now always handle content decoding
for navigation responses. This guarantees that the correct, decoded
content is consistently provided, whether the response is intended for
rendering or triggers a download.

A browser test
(`DownloadContentTest.CompressedResponseWithContentDisposition`) has
been added to verify this fix. It ensures that navigating to a URL that
serves content with both `Content-Encoding: gzip` and
`Content-Disposition: attachment` results in a correctly decoded
downloaded file.

Bug: 391950057
Change-Id: I2e8bc9fb6d1c3fe3124662f62e7b403b7e1e182c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6399553
Reviewed-by: Adam Rice <ricea@chromium.org>
Reviewed-by: Min Qin <qinmin@chromium.org>
Commit-Queue: Tsuyoshi Horo <horo@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1439161}
This commit is contained in:
Tsuyoshi Horo
2025-03-27 18:31:41 -07:00
committed by Chromium LUCI CQ
parent 619ed18814
commit f958d2bc4b
5 changed files with 33 additions and 5 deletions

@@ -4419,6 +4419,33 @@ IN_PROC_BROWSER_TEST_F(DownloadContentTest, DuplicateContentDisposition) {
downloads[0]->GetTargetFilePath().BaseName().value());
}
IN_PROC_BROWSER_TEST_F(DownloadContentTest,
CompressedResponseWithContentDisposition) {
// gzip-content-with-content-disposition.gz is served with Content-Disposition
// headers, and `Content-Encoding: gzip`.
NavigateToURLAndWaitForDownload(
shell(),
embedded_test_server()->GetURL(
"/download/gzip-content-with-content-disposition.gz"),
download::DownloadItem::COMPLETE);
std::vector<raw_ptr<download::DownloadItem, VectorExperimental>> downloads;
DownloadManagerForShell(shell())->GetAllDownloads(&downloads);
ASSERT_EQ(1u, downloads.size());
EXPECT_EQ(FILE_PATH_LITERAL("hello.txt"),
downloads[0]->GetTargetFilePath().BaseName().value());
// Verify the file is downloaded correctly.
{
base::ScopedAllowBlockingForTesting allow_blocking;
std::string downloaded_content;
ASSERT_TRUE(base::ReadFileToString(downloads[0]->GetTargetFilePath(),
&downloaded_content));
EXPECT_EQ(downloaded_content, "Hello World!\n");
}
}
// Test that the network isolation key is populated for:
// (1) <a download> triggered download request that doesn't go through the
// navigation path

@@ -559,11 +559,6 @@ std::unique_ptr<network::ResourceRequest> CreateResourceRequestForNavigation(
new_request->enable_load_timing = true;
if (base::FeatureList::IsEnabled(
network::features::kRendererSideContentDecoding)) {
new_request->client_side_content_decoding_enabled = true;
}
return new_request;
}

@@ -6671,6 +6671,8 @@ data/download/download-with-xfo-deny.html.mock-http-headers
data/download/empty.bin
data/download/empty.bin.mock-http-headers
data/download/forms.mhtml
data/download/gzip-content-with-content-disposition.gz
data/download/gzip-content-with-content-disposition.gz.mock-http-headers
data/download/gzip-content.gz
data/download/gzip-content.gz.mock-http-headers
data/download/hello.mhtml

@@ -0,0 +1,4 @@
HTTP/1.1 200 OK
Content-Length: 33
Content-Disposition: attachment; filename=hello.txt
Content-Encoding: gzip