Un-refcount SSLClientAuthHandler.

content/browser/ssl/ssl_client_auth_handler.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/ssl/ssl_client_auth_handler.h"
 
 #include "base/bind.h"
-#include "base/callback_helpers.h"
+#include "base/logging.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/resource_request_info.h"
+#include "net/cert/x509_certificate.h"
 #include "net/ssl/client_cert_store.h"
 #include "net/url_request/url_request.h"
 
 namespace content {
 
+namespace {
+
+void CertificateSelectedOnUIThread(
+    const SSLClientAuthHandler::CertificateCallback& io_thread_callback,
+    net::X509Certificate* cert) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(io_thread_callback, make_scoped_refptr(cert)));
+}
+
+void SelectCertificateOnUIThread(
+    int render_process_host_id,
+    int render_frame_host_id,
+    net::SSLCertRequestInfo* cert_request_info,
+    const SSLClientAuthHandler::CertificateCallback& io_thread_callback) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+
+  GetContentClient()->browser()->SelectClientCertificate(
+      render_process_host_id, render_frame_host_id, cert_request_info,
+      base::Bind(&CertificateSelectedOnUIThread, io_thread_callback));
+}
+
+}  // namespace
+
+class SSLClientAuthHandler::Core : public base::RefCountedThreadSafe<Core> {

[mmenke, 2014/12/11 21:02:20]

Should give a description of this class, and what it's needed (To keep
client_cert_store_ and cert_request_info_ until GetClientCerts completes
asynchronously)

[davidben, 2014/12/11 22:08:10]

Done.

+ public:
+  Core(SSLClientAuthHandler* handler,
+       scoped_ptr<net::ClientCertStore> client_cert_store,
+       net::SSLCertRequestInfo* cert_request_info)
+      : handler_(handler),
+        client_cert_store_(client_cert_store.Pass()),
+        cert_request_info_(cert_request_info) {}
+
+  bool has_client_cert_store() const { return client_cert_store_; }
+
+  void Detach() { handler_ = nullptr; }

[mmenke, 2014/12/11 21:02:20]

Using a WeakPtr here seems more natural, and it already has a weak factory, too,
conveniently enough.

[davidben, 2014/12/11 22:08:10]

Done.

+
+  void GetClientCerts() {
+    if (client_cert_store_) {
+      client_cert_store_->GetClientCerts(
+          *cert_request_info_, &cert_request_info_->client_certs,

[mmenke, 2014/12/11 21:02:20]

Eeee...This is ugly.  It takes a const SSLCertRequestInfo&, and then a non-const
member of that same const object.

Beyond the scope of this CL, but this makes me sad.

[davidben, 2014/12/11 22:08:10]

Completely agreed. This is crazy. Even making this part of SSLClientAuthHandler
at all is weird. We may as well farm that out to the chrome/ layer, thread
ownership of various pieces aside. It's already the case that ClientCertStore is
not used on one platform because the Android platform API we happen to call out
to in chrome/ happens to work differently...

...except that everyone down to net/ needs to know about that platform API
because the consumer only passes the certificate down and net/ digs up the key
from some platform global which is one of the reasons it's impossible to unit
test...

I started trying to fix this but that ought to be for another CL. :-) There's a
lot of stuff to tease out of this codepath.

+          base::Bind(&SSLClientAuthHandler::Core::DidGetClientCerts, this));
+    } else {
+      DidGetClientCerts();
+    }
+  }
+
+ private:
+  friend class base::RefCountedThreadSafe<Core>;
+
+  ~Core() {}
+
+  // Called when |client_cert_store_| is done retrieving the cert list.
+  void DidGetClientCerts() {
+    if (handler_)
+      handler_->DidGetClientCerts();
+  }
+
+  SSLClientAuthHandler* handler_;
+  scoped_ptr<net::ClientCertStore> client_cert_store_;
+  scoped_refptr<net::SSLCertRequestInfo> cert_request_info_;
+};
+
 SSLClientAuthHandler::SSLClientAuthHandler(
     scoped_ptr<net::ClientCertStore> client_cert_store,
     net::URLRequest* request,
     net::SSLCertRequestInfo* cert_request_info,
     const SSLClientAuthHandler::CertificateCallback& callback)
-    : request_(request),
+    : core_(new Core(this, client_cert_store.Pass(), cert_request_info)),
+      request_(request),
       cert_request_info_(cert_request_info),
-      client_cert_store_(client_cert_store.Pass()),
-      callback_(callback) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+      callback_(callback),
+      weak_factory_(this) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
 }
 
 SSLClientAuthHandler::~SSLClientAuthHandler() {
-  // If we were simply dropped, then act as if we selected no certificate.
-  DoCertificateSelected(NULL);
-}
-
-void SSLClientAuthHandler::OnRequestCancelled() {
-  request_ = NULL;
-  callback_.Reset();
+  core_->Detach();
 }
 
 void SSLClientAuthHandler::SelectCertificate() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  DCHECK(request_);
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
-  if (client_cert_store_) {
-    client_cert_store_->GetClientCerts(
-        *cert_request_info_,
-        &cert_request_info_->client_certs,
-        base::Bind(&SSLClientAuthHandler::DidGetClientCerts, this));
-  } else {
-    DidGetClientCerts();
-  }
-}
-
-void SSLClientAuthHandler::CertificateSelected(net::X509Certificate* cert) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  DVLOG(1) << this << " CertificateSelected " << cert;
-  BrowserThread::PostTask(
-      BrowserThread::IO, FROM_HERE,
-      base::Bind(
-          &SSLClientAuthHandler::DoCertificateSelected, this,
-          make_scoped_refptr(cert)));
+  // |core_| will call DidGetClientCerts when done.
+  core_->GetClientCerts();
 }
 
 void SSLClientAuthHandler::DidGetClientCerts() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  // Request may have cancelled while we were getting client certs.
-  if (!request_)
-    return;
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
   // Note that if |client_cert_store_| is NULL, we intentionally fall through to
   // DoCertificateSelected. This is for platforms where the client cert matching
-  // is not performed by Chrome, the platform can handle the cert matching
-  // before showing the dialog.
-  if (client_cert_store_ && cert_request_info_->client_certs.empty()) {
+  // is not performed by Chrome. Those platforms handle the cert matching before
+  // showing the dialog.
+  if (core_->has_client_cert_store() &&
+      cert_request_info_->client_certs.empty()) {
     // No need to query the user if there are no certs to choose from.
-    DoCertificateSelected(NULL);
+    CertificateSelected(NULL);
     return;
   }
 
   int render_process_host_id;
   int render_frame_host_id;
   if (!ResourceRequestInfo::ForRequest(request_)->GetAssociatedRenderFrame(
-          &render_process_host_id,
-          &render_frame_host_id))
+          &render_process_host_id, &render_frame_host_id)) {
     NOTREACHED();
+    CertificateSelected(NULL);
+    return;
+  }
 
-  // If the RVH does not exist by the time this task gets run, then the task
-  // will be dropped and the scoped_refptr to SSLClientAuthHandler will go
-  // away, so we do not leak anything. The destructor takes care of ensuring
-  // the net::URLRequest always gets a response.
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
-      base::Bind(
-          &SSLClientAuthHandler::DoSelectCertificate, this,
-          render_process_host_id, render_frame_host_id));
+      base::Bind(&SelectCertificateOnUIThread, render_process_host_id,
+                 render_frame_host_id, cert_request_info_,
+                 base::Bind(&SSLClientAuthHandler::CertificateSelected,
+                            weak_factory_.GetWeakPtr())));
 }
 
-void SSLClientAuthHandler::DoCertificateSelected(net::X509Certificate* cert) {
+void SSLClientAuthHandler::CertificateSelected(net::X509Certificate* cert) {
   DVLOG(1) << this << " DoCertificateSelected " << cert;
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  // request_ could have been NULLed if the request was cancelled while the
-  // user was choosing a cert, or because we have already responded to the
-  // certificate.
-  if (request_) {
-    request_ = NULL;
-    DCHECK(!callback_.is_null());
-    base::ResetAndReturn(&callback_).Run(cert);
-  }
-}
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
 
-void SSLClientAuthHandler::DoSelectCertificate(
-    int render_process_host_id, int render_frame_host_id) {
-  GetContentClient()->browser()->SelectClientCertificate(
-      render_process_host_id,
-      render_frame_host_id,
-      cert_request_info_.get(),
-      base::Bind(&SSLClientAuthHandler::CertificateSelected, this));
+  callback_.Run(cert);
+  // |this| may be deleted at this point.
 }
 
 }  // namespace content