Update the child process security policy to use explicit permission grants.

content/browser/child_process_security_policy_impl.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/child_process_security_policy_impl.h"
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/metrics/histogram.h"
@@ skipping 28 matching lines @@
     base::PLATFORM_FILE_ASYNC |
     base::PLATFORM_FILE_WRITE_ATTRIBUTES;
 
 const int kCreateFilePermissions =
     base::PLATFORM_FILE_CREATE;
 
 const int kEnumerateDirectoryPermissions =
     kReadFilePermissions |
     base::PLATFORM_FILE_ENUMERATE;
 
+const int kReadWriteFilePermissions =
+    base::PLATFORM_FILE_OPEN |
+    base::PLATFORM_FILE_CREATE |
+    base::PLATFORM_FILE_OPEN_ALWAYS |
+    base::PLATFORM_FILE_CREATE_ALWAYS |
+    base::PLATFORM_FILE_OPEN_TRUNCATED |
+    base::PLATFORM_FILE_READ |
+    base::PLATFORM_FILE_WRITE |
+    base::PLATFORM_FILE_EXCLUSIVE_READ |
+    base::PLATFORM_FILE_EXCLUSIVE_WRITE |
+    base::PLATFORM_FILE_ASYNC |
+    base::PLATFORM_FILE_WRITE_ATTRIBUTES;
+
+const int kCreateWriteFilePermissions =
+      base::PLATFORM_FILE_CREATE |
+      base::PLATFORM_FILE_CREATE_ALWAYS |
+      base::PLATFORM_FILE_OPEN |
+      base::PLATFORM_FILE_OPEN_ALWAYS |
+      base::PLATFORM_FILE_OPEN_TRUNCATED |
+      base::PLATFORM_FILE_WRITE |
+      base::PLATFORM_FILE_WRITE_ATTRIBUTES |
+      base::PLATFORM_FILE_ASYNC;
+      // need EXCLUSIVE_WRITE in this mix?
+
 }  // namespace
 
 // The SecurityState class is used to maintain per-child process security state
 // information.
 class ChildProcessSecurityPolicyImpl::SecurityState {
  public:
   SecurityState()
     : enabled_bindings_(0),
       can_read_raw_cookies_(false) { }
 
@@ skipping 339 matching lines @@
     if (net::FileURLToFilePath(url, &path))
       state->second->GrantRequestOfSpecificFile(path);
   }
 }
 
 void ChildProcessSecurityPolicyImpl::GrantReadFile(int child_id,
                                                    const base::FilePath& file) {
   GrantPermissionsForFile(child_id, file, kReadFilePermissions);
 }
 
+void ChildProcessSecurityPolicyImpl::GrantReadWriteFile(
+    int child_id, const base::FilePath& file) {
+  GrantPermissionsForFile(child_id, file, kReadWriteFilePermissions);
+}
+
+void ChildProcessSecurityPolicyImpl::GrantCreateWriteFile(
+    int child_id, const base::FilePath& file) {
+  GrantPermissionsForFile(child_id, file, kCreateWriteFilePermissions);
+}
+
 void ChildProcessSecurityPolicyImpl::GrantReadDirectory(
     int child_id, const base::FilePath& directory) {
   GrantPermissionsForFile(child_id, directory, kEnumerateDirectoryPermissions);
 }
 
 void ChildProcessSecurityPolicyImpl::GrantPermissionsForFile(
     int child_id, const base::FilePath& file, int permissions) {
   base::AutoLock lock(lock_);
 
   SecurityStateMap::iterator state = security_state_.find(child_id);
@@ skipping 268 matching lines @@
     int permission) {
   base::AutoLock lock(lock_);
 
   SecurityStateMap::iterator state = security_state_.find(child_id);
   if (state == security_state_.end())
     return false;
   return state->second->HasPermissionsForFileSystem(filesystem_id, permission);
 }
 
 }  // namespace content