The Browser object represents the top-level Chrome browser window. One or more
tabs (WebContents) are then owned by the Browser object via TabStripModel. A
new Browser object can be created programmatically using "new Browser" or
Browser::Create, or as a result of user action such as dragging a tab out of an
existing window. New or existing tabs can also be added to an already existing
Browser object.
The Browser object acts as the WebContentsDelegate for all attached tabs. CEF
integration requires WebContentsDelegate callbacks and notification of tab
attach/detach. To support this integration we add a cef::BrowserDelegate
(ChromeBrowserDelegate) member that is created in the Browser constructor and
receives delegation for the Browser callbacks. ChromeBrowserDelegate creates a
new ChromeBrowserHostImpl when a tab is added to a Browser for the first time,
and that ChromeBrowserHostImpl continues to exist until the tab's WebContents
is destroyed. The associated WebContents object does not change, but the
Browser object will change when the tab is dragged between windows.
CEF callback logic is shared between the chrome and alloy runtimes where
possible. This shared logic has been extracted from CefBrowserHostImpl to
create new CefBrowserHostBase and CefBrowserContentsDelegate classes. The
CefBrowserHostImpl class is now only used with the alloy runtime and will be
renamed to AlloyBrowserHostImpl in a future commit.
A CORS preflight request is an "OPTIONS" request sent to a server prior to a
cross-origin XMLHttpRequest or Fetch request. The server's response determines
which HTTP request methods are allowed and supported, and whether credentials
such as Cookies and HTTP Authentication should be sent with requests.
A CORS preflight request will only be sent if certain conditions are met. For
example, it will be sent for requests that have potentially unsafe HTTP
methods [1] or request headers [2]. See the NeedsPreflight function in
services/network/cors/cors_url_loader.cc for full details.
CORS preflight functionality is implemented in the network service and will not
be triggered if the client handles the request instead of allowing it to proceed
over the network. Since the preflight request itself also runs in the network
service it cannot be intercepted by the client.
[1] https://fetch.spec.whatwg.org/#cors-safelisted-method
[2] https://fetch.spec.whatwg.org/#cors-safelisted-request-header
The request.trusted_params.isolation_info.site_for_cookies value must
match request.site_for_cookies.
This change also adds unit test coverage for cross-origin GET redirects.
This fixes an IsCanonical() DCHECK failure triggered by calling
CanonicalCookie::Create for a non-cookieable URL.
This change also adds unit test coverage for cross-origin cookie
behavior with sub-resource requests (iframe, XHR, Fetch).
- CefURLRequest::Create is no longer supported in the renderer process
(see https://crbug.com/891872). Use CefFrame::CreateURLRequest instead.
- Mac platform definitions have been changed from `MACOSX` to `MAC`
(see https://crbug.com/1105907) and related CMake macro names have
been updated. The old `OS_MACOSX` define is still set in code and CMake
for backwards compatibility.
- Linux ARM build is currently broken (see https://crbug.com/1123214).
- Windows: 10.0.19041 SDK is now required.
- macOS: 10.15.1 SDK (at least Xcode 11.2) is now required.
- Remove CefMediaSource::IsValid and CefMediaSink::IsValid which would
always return true.
Existing CefBrowserContext functionality is now split between
CefBrowserContext and AlloyBrowserContext. Runtime implementations of
CefBrowserContext will provide access to the content::BrowserContext and
Profile types via different inheritance paths. For example, the Alloy
runtime uses ChromeProfileAlloy and the Chrome runtime uses ProfileImpl.
This change also renames CefResourceContext to CefIOThreadState to more
accurately represent its purpose as it no longer needs to extend
content::ResourceContext.
This is the first pass in removing direct dependencies on the Alloy
runtime from code that can potentially be shared between runtimes.
CefBrowserHost and CefRequestContext APIs (including CefCookieManager,
CefURLRequest, etc.) are not yet implemented for the Chrome runtime.
Assert early if these API methods are called while the Chrome runtime
is enabled.
As part of introducing the Chrome runtime we now need to distinguish
between the classes that implement the current CEF runtime and the
classes the implement the shared CEF library/runtime structure and
public API. We choose the name Alloy for the current CEF runtime
because it describes a combination of Chrome and other elements.
Shared CEF library/runtime classes will continue to use the Cef
prefix. Classes that implement the Alloy or Chrome runtime will use
the Alloy or Chrome prefixes respectively. Classes that extend an
existing Chrome-prefixed class will add the Cef or Alloy suffix,
thereby following the existing naming pattern of Chrome-derived
classes.
This change applies the new naming pattern to an initial set of
runtime-related classes. Additional classes/files will be renamed
and moved as the Chrome runtime implementation progresses.
This change also restores the Chromium default values for the
SameSiteByDefaultCookies and CookiesWithoutSameSiteMustBeSecure features. See
https://www.chromium.org/updates/same-site for feature details and rollout
timeline.
With this change CefCookieManagerImpl no longer keeps a reference to the
originating CefRequestContextImpl. This means that the CefRequestContextImpl
can be destroyed if all other references are released while the
CefCookieManagerImpl exists. If CefRequestContextImpl destruction results in
the underlying CefBrowserContext being destroyed then the CefCookieManagerImpl's
reference to that CefBrowserContext will be invalidated.
This is the same ownership model introduced with CefMediaRouterImpl in the
previous commit.
Requests from the PDF viewer are not associated with a CefBrowser. Consequently,
the InterceptedRequestHandler for those requests will register as an observer of
CefContext destruction. When the browser is closed the InterceptedRequestHandler
is destroyed and an async task is posted to remove/delete the observer on the UI
thread. If CefShutdown is then called the task may execute after shutdown has
started, in which case CONTEXT_STATE_VALID() will return false. We still need to
remove the observer in this case to avoid a use-after-free in
FinishShutdownOnUIThread.
Modifying the URL in OnBeforeResourceLoad causes an internal redirect response.
In cases where the request is cross-origin and credentials mode is 'include'
the redirect response must include the "Access-Control-Allow-Credentials"
header, otherwise the request will be blocked.
When NetworkService is enabled requests created using CefFrame::CreateURLRequest
will call CefRequestHandler::GetAuthCredentials for the associated browser after
calling CefURLRequestClient::GetAuthCredentials if that call returns false.
For 303 redirects all request methods except HEAD are converted to GET as per
the latest http draft. For historical reasons the draft also allows POST
requests to be converted to GETs when following 301/302 redirects. Most major
browsers do this and so shall we. When a request is converted to GET any POST
data should also be removed.
Use 307 redirects instead if you want the request to be repeated using the same
method and POST data.
Modifying the URL in OnBeforeResourceLoad causes an internal redirect response.
In cases where the request is cross-origin (containing a non-null "Origin"
header) the redirect response must include the "Access-Control-Allow-Origin"
header, otherwise the request will be blocked.
This change also fixes a problem where existing request headers would be
discarded if the request was modified in OnBeforeResourceLoad.
Initialization of request objects requires asynchronous hops between the UI and
IO threads. In some cases the browser may be destroyed, the mojo connection may
be aborted, or the ProxyURLLoaderFactory object may be deleted while
initialization is still in progress. This change fixes crashes and adds unit
tests that try to reproduce these conditions.
To test: Run `ceftests --gtest_repeat=50
--gtest_filter=ResourceRequestHandlerTest.Basic*Abort*`
This is a speculative fix for a crash where |on_disconnect_| appears to be null
in ProxyURLLoaderFactory::MaybeDestroySelf. The hypothesis here is that
OnURLLoaderClientError is being called while the proxy object is still in-flight
to ResourceContextData::AddProxy (e.g. before SetDisconnectCallback has been
called for the proxy object). Additonally, this change protects against
MaybeDestroySelf attempting to execute |on_disconnect_| multiple times.
The behavior has changed as follows with NetworkService enabled:
- All pending and in-progress requests will now be aborted when the CEF context
or associated browser is destroyed. The OnResourceLoadComplete callback will
now also be called in this case for in-progress requests that have a handler.
- The CefResourceHandler::Cancel method will now always be called when resource
handling is complete, irrespective of whether handling completed successfully.
- Request callbacks that arrive after the OnBeforeClose callback for the
associated browser (which may happen for in-progress requests that are aborted
on browser destruction) will now always have a non-nullptr CefBrowser
parameter.
- Allow empty parameters to CefRequest and CefResponse methods where it makes
sense (e.g. resetting default response state, or clearing a referrer value).
- Fixed a reference loop that was keeping CefResourceHandler objects from being
destroyed if they were holding a callback reference (from ProcessRequest,
ReadResponse, etc.) during CEF context or associated browser destruction.
- Fixed an issue where the main frame was not detached on browser destruction
which could cause a crash due to RFH use-after-free (see issue #2498).
To test: All unit tests pass as expected.
This change fixes an issue where the cancel_callback for a pending request
might already have been executed when the OnBrowserDestroyed notification is
received.
This change moves the SendProcessMessage method from CefBrowser to CefFrame and
adds CefBrowser parameters to OnProcessMessageReceived and
OnDraggableRegionsChanged.
The internal implementation has changed as follows:
- Frame IDs are now a 64-bit combination of the 32-bit render_process_id and
render_routing_id values that uniquely identify a RenderFrameHost (RFH).
- CefFrameHostImpl objects are now managed by CefBrowserInfo with life span tied
to RFH expectations. Specifically, a CefFrameHostImpl object representing a
sub-frame will be created when a RenderFrame is created in the renderer
process and detached when the associated RenderFrame is deleted or the
renderer process in which it runs has died.
- The CefFrameHostImpl object representing the main frame will always be valid
but the underlying RFH (and associated frame ID) may change over time as a
result of cross-origin navigations. Despite these changes calling LoadURL on
the main frame object in the browser process will always navigate as expected.
- Speculative RFHs, which may be created as a result of a cross-origin
navigation and discarded if that navigation is not committed, are now handled
correctly (e.g. ignored in most cases until they're committed).
- It is less likely, but still possible, to receive a CefFrame object with an
invalid frame ID (ID < 0). This can happen in cases where a RFH has not yet
been created for a sub-frame. For example, when OnBeforeBrowse is called
before initiating navigation in a previously nonexisting sub-frame.
To test: All tests pass with NetworkService enabled and disabled.