Add a path for a web page to request the enumeration of a directory. This, together with a WebKit change, will allow a drag-and-drop on a Directory Upload control (<input type=file webkitdirectory>) which provides only the path to the renderer, to correctly populate the control as if the user had selected that directory in a file picker.

BUG=58977
TEST=drag-and-drop on directory upload control (with upstream change)
Review URL: http://codereview.chromium.org/6623015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@81183 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 126 insertions, 0 deletions

diff --git a/content/browser/child_process_security_policy.cc b/content/browser/child_process_security_policy.cc
index 33cf5e0..81eca77 100644
--- a/content/browser/child_process_security_policy.cc
+++ b/content/browser/child_process_security_policy.cc
@@ -20,6 +20,10 @@ static const int kReadFilePermissions =
     base::PLATFORM_FILE_EXCLUSIVE_READ |
     base::PLATFORM_FILE_ASYNC;
 
+static const int kEnumerateDirectoryPermissions =
+    kReadFilePermissions |
+    base::PLATFORM_FILE_ENUMERATE;
+
 // The SecurityState class is used to maintain per-child process security state
 // information.
 class ChildProcessSecurityPolicy::SecurityState {
@@ -241,6 +245,11 @@ void ChildProcessSecurityPolicy::GrantReadFile(int child_id,
   GrantPermissionsForFile(child_id, file, kReadFilePermissions);
 }
 
+void ChildProcessSecurityPolicy::GrantReadDirectory(int child_id,
+                                                    const FilePath& directory) {
+  GrantPermissionsForFile(child_id, directory, kEnumerateDirectoryPermissions);
+}
+
 void ChildProcessSecurityPolicy::GrantPermissionsForFile(
     int child_id, const FilePath& file, int permissions) {
   base::AutoLock lock(lock_);
@@ -372,6 +381,13 @@ bool ChildProcessSecurityPolicy::CanReadFile(int child_id,
   return HasPermissionsForFile(child_id, file, kReadFilePermissions);
 }
 
+bool ChildProcessSecurityPolicy::CanReadDirectory(int child_id,
+                                                  const FilePath& directory) {
+  return HasPermissionsForFile(child_id,
+                               directory,
+                               kEnumerateDirectoryPermissions);
+}
+
 bool ChildProcessSecurityPolicy::HasPermissionsForFile(
     int child_id, const FilePath& file, int permissions) {
   base::AutoLock lock(lock_);
diff --git a/content/browser/child_process_security_policy.h b/content/browser/child_process_security_policy.h
index aa53e9d..ec540f1 100644
--- a/content/browser/child_process_security_policy.h
+++ b/content/browser/child_process_security_policy.h
@@ -71,6 +71,10 @@ class ChildProcessSecurityPolicy {
   // to upload the file to the web.
   void GrantReadFile(int child_id, const FilePath& file);
 
+  // Grants the child process permission to enumerate all the files in
+  // this directory and read those files.
+  void GrantReadDirectory(int child_id, const FilePath& directory);
+
   // Grants certain permissions to a file. |permissions| must be a bit-set of
   // base::PlatformFileFlags.
   void GrantPermissionsForFile(int child_id,
@@ -106,6 +110,10 @@ class ChildProcessSecurityPolicy {
   // capability to upload the requested file.
   bool CanReadFile(int child_id, const FilePath& file);
 
+  // Before servicing a child process's request to enumerate a directory
+  // the browser should call this method to check for the capability.
+  bool CanReadDirectory(int child_id, const FilePath& directory);
+
   // Determines if certain permissions were granted for a file. |permissions|
   // must be a bit-set of base::PlatformFileFlags.
   bool HasPermissionsForFile(int child_id,
diff --git a/content/browser/child_process_security_policy_unittest.cc b/content/browser/child_process_security_policy_unittest.cc
index 8ad4ad4..e20178e 100644
--- a/content/browser/child_process_security_policy_unittest.cc
+++ b/content/browser/child_process_security_policy_unittest.cc
@@ -215,6 +215,38 @@ TEST_F(ChildProcessSecurityPolicyTest, CanReadFiles) {
   p->Remove(kRendererID);
 }
 
+TEST_F(ChildProcessSecurityPolicyTest, CanReadDirectories) {
+  ChildProcessSecurityPolicy* p = ChildProcessSecurityPolicy::GetInstance();
+
+  p->Add(kRendererID);
+
+  EXPECT_FALSE(p->CanReadDirectory(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/"))));
+  p->GrantReadDirectory(kRendererID, FilePath(FILE_PATH_LITERAL("/etc/")));
+  EXPECT_TRUE(p->CanReadDirectory(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/"))));
+  EXPECT_TRUE(p->CanReadFile(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/passwd"))));
+
+  p->Remove(kRendererID);
+  p->Add(kRendererID);
+
+  EXPECT_FALSE(p->CanReadDirectory(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/"))));
+  EXPECT_FALSE(p->CanReadFile(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/passwd"))));
+
+  // Just granting read permission as a file doesn't imply reading as a
+  // directory.
+  p->GrantReadFile(kRendererID, FilePath(FILE_PATH_LITERAL("/etc/")));
+  EXPECT_TRUE(p->CanReadFile(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/passwd"))));
+  EXPECT_FALSE(p->CanReadDirectory(kRendererID,
+      FilePath(FILE_PATH_LITERAL("/etc/"))));
+
+  p->Remove(kRendererID);
+}
+
 TEST_F(ChildProcessSecurityPolicyTest, FilePermissions) {
   ChildProcessSecurityPolicy* p = ChildProcessSecurityPolicy::GetInstance();
 
diff --git a/content/browser/renderer_host/render_view_host.cc b/content/browser/renderer_host/render_view_host.cc
index 1f35dc3..b9e1f52 100644
--- a/content/browser/renderer_host/render_view_host.cc
+++ b/content/browser/renderer_host/render_view_host.cc
@@ -465,6 +465,10 @@ void RenderViewHost::DragTargetDragEnter(
     policy->GrantRequestURL(process()->id(),
                             net::FilePathToFileURL(path));
     policy->GrantReadFile(process()->id(), path);
+
+    // Allow dragged directories to be enumerated by the child process.
+    // Note that we can't tell a file from a directory at this point.
+    policy->GrantReadDirectory(process()->id(), path);
   }
   Send(new DragMsg_TargetDragEnter(routing_id(), drop_data, client_pt,
                                    screen_pt, operations_allowed));
@@ -683,6 +687,20 @@ void RenderViewHost::FilesSelectedInChooser(
   Send(new ViewMsg_RunFileChooserResponse(routing_id(), files));
 }
 
+void RenderViewHost::DirectoryEnumerationFinished(
+    int request_id,
+    const std::vector<FilePath>& files) {
+  // Grant the security access requested to the given files.
+  for (std::vector<FilePath>::const_iterator file = files.begin();
+       file != files.end(); ++file) {
+    ChildProcessSecurityPolicy::GetInstance()->GrantReadFile(
+        process()->id(), *file);
+  }
+  Send(new ViewMsg_EnumerateDirectoryResponse(routing_id(),
+                                              request_id,
+                                              files));
+}
+
 void RenderViewHost::LoadStateChanged(const GURL& url,
                                       net::LoadState load_state,
                                       uint64 upload_position,
diff --git a/content/browser/renderer_host/render_view_host.h b/content/browser/renderer_host/render_view_host.h
index 72920cb..75846ab 100644
--- a/content/browser/renderer_host/render_view_host.h
+++ b/content/browser/renderer_host/render_view_host.h
@@ -385,6 +385,10 @@ class RenderViewHost : public RenderWidgetHost {
   // from an Open File dialog for the form.
   void FilesSelectedInChooser(const std::vector<FilePath>& files);
 
+  // Notifies the listener that a directory enumeration is complete.
+  void DirectoryEnumerationFinished(int request_id,
+                                    const std::vector<FilePath>& files);
+
   // Notifies the RenderViewHost that its load state changed.
   void LoadStateChanged(const GURL& url, net::LoadState load_state,
                         uint64 upload_position, uint64 upload_size);
diff --git a/content/common/view_messages.h b/content/common/view_messages.h
index 3abb27d..ae921bd 100644
--- a/content/common/view_messages.h
+++ b/content/common/view_messages.h
@@ -1030,6 +1030,11 @@ IPC_MESSAGE_ROUTED1(ViewMsg_SetAltErrorPageURL,
 IPC_MESSAGE_ROUTED1(ViewMsg_RunFileChooserResponse,
                     std::vector<FilePath> /* selected files */)
 
+// Provides the results of directory enumeration.
+IPC_MESSAGE_ROUTED2(ViewMsg_EnumerateDirectoryResponse,
+                    int /* request_id */,
+                    std::vector<FilePath> /* files_in_directory */)
+
 // When a renderer sends a ViewHostMsg_Focus to the browser process,
 // the browser has the option of sending a ViewMsg_CantFocus back to
 // the renderer.
@@ -1642,6 +1647,14 @@ IPC_MESSAGE_ROUTED1(ViewHostMsg_SelectionChanged,
 IPC_MESSAGE_ROUTED1(ViewHostMsg_RunFileChooser,
                     ViewHostMsg_RunFileChooser_Params)
 
+// Asks the browser to enumerate a directory.  This is equivalent to running
+// the file chooser in directory-enumeration mode and having the user select
+// the given directory.  The result is returned in a
+// ViewMsg_EnumerateDirectoryResponse message.
+IPC_MESSAGE_ROUTED2(ViewHostMsg_EnumerateDirectory,
+                    int /* request_id */,
+                    FilePath /* file_path */)
+
 // Tells the browser to move the focus to the next (previous if reverse is
 // true) focusable element.
 IPC_MESSAGE_ROUTED1(ViewHostMsg_TakeFocus,
diff --git a/content/renderer/render_view.cc b/content/renderer/render_view.cc
index 6052063..c916155 100644
--- a/content/renderer/render_view.cc
+++ b/content/renderer/render_view.cc
@@ -935,6 +935,8 @@ bool RenderView::OnMessageReceived(const IPC::Message& message) {
     IPC_MESSAGE_HANDLER(ViewMsg_InstallMissingPlugin, OnInstallMissingPlugin)
     IPC_MESSAGE_HANDLER(ViewMsg_DisplayPrerenderedPage,
                         OnDisplayPrerenderedPage)
+    IPC_MESSAGE_HANDLER(ViewMsg_EnumerateDirectoryResponse,
+                        OnEnumerateDirectoryResponse)
     IPC_MESSAGE_HANDLER(ViewMsg_RunFileChooserResponse, OnFileChooserResponse)
     IPC_MESSAGE_HANDLER(ViewMsg_EnableViewSourceMode, OnEnableViewSourceMode)
     IPC_MESSAGE_HANDLER(ViewMsg_GetAllSavableResourceLinksForCurrentPage,
@@ -2159,6 +2161,17 @@ bool RenderView::runFileChooser(
   return ScheduleFileChooser(ipc_params, chooser_completion);
 }
 
+bool RenderView::enumerateDirectory(
+    const WebString& path,
+    WebFileChooserCompletion* chooser_completion) {
+  int id = enumeration_completion_id_++;
+  enumeration_completions_[id] = chooser_completion;
+  return Send(new ViewHostMsg_EnumerateDirectory(
+      routing_id_,
+      id,
+      webkit_glue::WebStringToFilePath(path)));
+}
+
 void RenderView::runModalAlertDialog(
     WebFrame* frame, const WebString& message) {
   RunJavaScriptMessage(ui::MessageBoxFlags::kIsJavascriptAlert,
@@ -4237,6 +4250,20 @@ void RenderView::OnDisplayPrerenderedPage() {
   }
 }
 
+void RenderView::OnEnumerateDirectoryResponse(
+    int id,
+    const std::vector<FilePath>& paths) {
+  if (!enumeration_completions_[id])
+    return;
+
+  WebVector<WebString> ws_file_names(paths.size());
+  for (size_t i = 0; i < paths.size(); ++i)
+    ws_file_names[i] = webkit_glue::FilePathToWebString(paths[i]);
+
+  enumeration_completions_[id]->didChooseFile(ws_file_names);
+  enumeration_completions_.erase(id);
+}
+
 void RenderView::OnFileChooserResponse(const std::vector<FilePath>& paths) {
   // This could happen if we navigated to a different page before the user
   // closed the chooser.
diff --git a/content/renderer/render_view.h b/content/renderer/render_view.h
index 347d761..6542966 100644
--- a/content/renderer/render_view.h
+++ b/content/renderer/render_view.h
@@ -391,6 +391,9 @@ class RenderView : public RenderWidget,
   virtual bool runFileChooser(
       const WebKit::WebFileChooserParams& params,
       WebKit::WebFileChooserCompletion* chooser_completion);
+  virtual bool enumerateDirectory(
+      const WebKit::WebString& path,
+      WebKit::WebFileChooserCompletion* chooser_completion);
   virtual void runModalAlertDialog(WebKit::WebFrame* frame,
                                    const WebKit::WebString& message);
   virtual bool runModalConfirmDialog(WebKit::WebFrame* frame,
@@ -804,6 +807,7 @@ class RenderView : public RenderWidget,
                             WebKit::WebDragOperationsMask operations_allowed);
   void OnEnablePreferredSizeChangedMode(int flags);
   void OnEnableViewSourceMode();
+  void OnEnumerateDirectoryResponse(int id, const std::vector<FilePath>& paths);
   void OnExecuteEditCommand(const std::string& name, const std::string& value);
   void OnFileChooserResponse(const std::vector<FilePath>& paths);
   void OnFind(int request_id, const string16&, const WebKit::WebFindOptions&);
@@ -1259,6 +1263,10 @@ class RenderView : public RenderWidget,
   struct PendingFileChooser;
   std::deque< linked_ptr<PendingFileChooser> > file_chooser_completions_;
 
+  // The current directory enumeration callback
+  std::map<int, WebKit::WebFileChooserCompletion*> enumeration_completions_;
+  int enumeration_completion_id_;
+
   // ImageResourceFetchers schedule via DownloadImage.
   ImageResourceFetcherList image_fetchers_;