Pepper: Refactor PNaCl OpenManifestEntry logic.

components/nacl/renderer/ppb_nacl_private_impl.cc

 // Copyright 2013 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 "components/nacl/renderer/ppb_nacl_private_impl.h"
 
 #include <numeric>
 #include <string>
 #include <vector>
 
@@ skipping 48 matching lines @@
 #include "third_party/WebKit/public/web/WebURLLoaderOptions.h"
 #include "third_party/jsoncpp/source/include/json/reader.h"
 #include "third_party/jsoncpp/source/include/json/value.h"
 
 namespace nacl {
 namespace {
 
 // The pseudo-architecture used to indicate portable native client.
 const char* const kPortableArch = "portable";
 
+// The base URL for resources used by the PNaCl translator processes.
+const char* kPNaClTranslatorBaseUrl = "chrome://pnacl-translator/";
+
 base::LazyInstance<scoped_refptr<PnaclTranslationResourceHost> >
     g_pnacl_resource_host = LAZY_INSTANCE_INITIALIZER;
 
 bool InitializePnaclResourceHost() {
   // Must run on the main thread.
   content::RenderThread* render_thread = content::RenderThread::Get();
   if (!render_thread)
     return false;
   if (!g_pnacl_resource_host.Get()) {
     g_pnacl_resource_host.Get() = new PnaclTranslationResourceHost(
@@ skipping 434 matching lines @@
                               uint32_t options) {
 #if defined(OS_WIN)
   return content::BrokerDuplicateHandle(source_handle, process_id,
                                         target_handle, desired_access,
                                         options);
 #else
   return 0;
 #endif
 }
 
-PP_FileHandle GetReadonlyPnaclFD(const char* filename) {
+// Convert a URL to a filename for GetReadonlyPnaclFd.
+// Must be kept in sync with PnaclCanOpenFile() in
+// components/nacl/browser/nacl_file_host.cc.
+std::string PnaclComponentURLToFilename(const std::string& url) {
+  // strip component scheme.

[bbudge, 2014/05/30 17:57:56]

Since we're in chrome now, can you use GURL to parse URLs now?

+  std::string r = url.substr(
+      std::string(kPNaClTranslatorBaseUrl).length());
+
+  // Use white-listed-chars.

[bbudge, 2014/05/30 20:04:57]

If we're generating these, why do we have to do this?

[teravest, 2014/05/30 20:09:05]

We depend on this translation happening for some files
(like "chrome://pnacl-translator/pnacl.json"). Presumably "llc" and "ld" could
make open_resource() calls that would have unsafe file paths? But we do the
appending for the "chrome://pnacl-translator" prefix, which is provided here.

My point is that this isn't a "real" URL.

[bbudge, 2014/05/30 20:17:13]

Could you add a short comment to that effect here, i.e. why replace unsafe
chars?
Also, above where you use std::string to remove the prefix, why that is safe.
Most chrome reviewers would want you to use GURL for this, so explain why it's
OK here.

+  size_t replace_pos;
+  static const char* white_list = "abcdefghijklmnopqrstuvwxyz0123456789_";
+  replace_pos = r.find_first_not_of(white_list);
+  while(replace_pos != std::string::npos) {
+    r = r.replace(replace_pos, 1, "_");
+    replace_pos = r.find_first_not_of(white_list);
+  }
+  return r;
+}
+
+PP_FileHandle GetReadonlyPnaclFd(const char* url) {
+  std::string filename = PnaclComponentURLToFilename(url);
   IPC::PlatformFileForTransit out_fd = IPC::InvalidPlatformFileForTransit();
   IPC::Sender* sender = content::RenderThread::Get();
   DCHECK(sender);
   if (!sender->Send(new NaClHostMsg_GetReadonlyPnaclFD(
           std::string(filename),
           &out_fd))) {
     return base::kInvalidPlatformFileValue;
   }
   if (out_fd == IPC::InvalidPlatformFileForTransit()) {
     return base::kInvalidPlatformFileValue;
@@ skipping 534 matching lines @@
     std::string key_string(key);
     if (key_string.find(kFilesPrefix) == std::string::npos) {
       nacl::NexeLoadManager* load_manager = GetNexeLoadManager(instance);
       if (load_manager)
         load_manager->ReportLoadError(PP_NACL_ERROR_MANIFEST_RESOLVE_URL,
                                       "key did not start with files/");
       return PP_FALSE;
     }
     std::string key_basename = key_string.substr(kFilesPrefix.length());
     std::string pnacl_url =
-        std::string("chrome://pnacl-translator/") + GetSandboxArch() + "/" +
+        std::string(kPNaClTranslatorBaseUrl) + GetSandboxArch() + "/" +
         key_basename;
     *pp_full_url = ppapi::StringVar::StringToPPVar(pnacl_url);
     return PP_TRUE;
   }
 
   JsonManifestMap::iterator it = g_manifest_map.Get().find(instance);
   if (it == g_manifest_map.Get().end())
     return PP_FALSE;
 
   std::string full_url;
   bool ok = it->second->ResolveKey(key, &full_url, pnacl_options);
   if (ok)
     *pp_full_url = ppapi::StringVar::StringToPPVar(full_url);
   return PP_FromBool(ok);
 }
 
 PP_Bool GetPNaClResourceInfo(PP_Instance instance,
                              const char* filename,
                              PP_Var* llc_tool_name,
                              PP_Var* ld_tool_name) {
   NexeLoadManager* load_manager = GetNexeLoadManager(instance);
   DCHECK(load_manager);
   if (!load_manager)
     return PP_FALSE;
 
-  base::PlatformFile file = GetReadonlyPnaclFD(filename);
+  base::PlatformFile file = GetReadonlyPnaclFd(filename);
   if (file == base::kInvalidPlatformFileValue) {
     load_manager->ReportLoadError(
         PP_NACL_ERROR_PNACL_RESOURCE_FETCH,
         "The Portable Native Client (pnacl) component is not "
         "installed. Please consult chrome://components for more "
         "information.");
     return PP_FALSE;
   }
 
   base::PlatformFileInfo file_info;
@@ skipping 296 matching lines @@
   NexeLoadManager* load_manager = GetNexeLoadManager(instance);
   DCHECK(load_manager);
   if (!load_manager) {
     ppapi::PpapiGlobals::Get()->GetMainThreadMessageLoop()->PostTask(
         FROM_HERE,
         base::Bind(callback.func, callback.user_data,
                    static_cast<int32_t>(PP_ERROR_FAILED)));
     return;
   }
 
+  // Handle special PNaCl support files which are installed on the user's
+  // machine.
+  std::string url_string(url);
+  if (url_string.find(kPNaClTranslatorBaseUrl, 0) == 0) {
+    PP_FileHandle handle = GetReadonlyPnaclFd(url);
+    if (handle == PP_kInvalidFileHandle) {
+      ppapi::PpapiGlobals::Get()->GetMainThreadMessageLoop()->PostTask(
+          FROM_HERE,
+          base::Bind(callback.func, callback.user_data,
+                     static_cast<int32_t>(PP_ERROR_FAILED)));
+      return;
+    }
+    // TODO(ncbray): enable the fast loading and validation paths for this type
+    // of file.
+    file_info->handle = handle;
+    file_info->token_lo = 0;
+    file_info->token_hi = 0;
+    ppapi::PpapiGlobals::Get()->GetMainThreadMessageLoop()->PostTask(
+        FROM_HERE,
+        base::Bind(callback.func, callback.user_data,
+                   static_cast<int32_t>(PP_OK)));
+    return;
+  }
+
   // We have to ensure that this url resolves relative to the plugin base url
   // before downloading it.
   const GURL& test_gurl = load_manager->plugin_base_url().Resolve(url);
   if (!test_gurl.is_valid()) {
     ppapi::PpapiGlobals::Get()->GetMainThreadMessageLoop()->PostTask(
         FROM_HERE,
         base::Bind(callback.func, callback.user_data,
                    static_cast<int32_t>(PP_ERROR_FAILED)));
     return;
   }
@@ skipping 46 matching lines @@
                  base::Owned(tracker), url));
   file_downloader->Load(url_request);
 }
 
 const PPB_NaCl_Private nacl_interface = {
   &LaunchSelLdr,
   &StartPpapiProxy,
   &UrandomFD,
   &Are3DInterfacesDisabled,
   &BrokerDuplicateHandle,
-  &GetReadonlyPnaclFD,
+  &GetReadonlyPnaclFd,
   &CreateTemporaryFile,
   &GetNumberOfProcessors,
   &PPIsNonSFIModeEnabled,
   &GetNexeFd,
   &ReportTranslationFinished,
   &DispatchEvent,
   &ReportLoadSuccess,
   &ReportLoadError,
   &ReportLoadAbort,
   &NexeDidCrash,
@@ skipping 23 matching lines @@
   &DownloadFile
 };
 
 }  // namespace
 
 const PPB_NaCl_Private* GetNaClPrivateInterface() {
   return &nacl_interface;
 }
 
 }  // namespace nacl