content/browser/renderer_host/pepper/pepper_security_helper.cc

   1 // Copyright 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "content/browser/renderer_host/pepper/pepper_security_helper.h"
   6
   7 #include "base/logging.h"
   8 #include "content/browser/child_process_security_policy_impl.h"
   9 #include "ppapi/c/ppb_file_io.h"
  10
  11 namespace content {
  12
  13 namespace {
  14
  15 template <typename CanRead,
  16           typename CanWrite,
  17           typename CanCreate,
  18           typename CanCreateReadWrite,
  19           typename FileID>
  20 bool CanOpenFileWithPepperFlags(CanRead can_read,
  21                                 CanWrite can_write,
  22                                 CanCreate can_create,
  23                                 CanCreateReadWrite can_create_read_write,
  24                                 int pp_open_flags,
  25                                 int child_id,
  26                                 const FileID& file) {
  27   ChildProcessSecurityPolicyImpl* policy =
  28       ChildProcessSecurityPolicyImpl::GetInstance();
  29
  30   bool pp_read = !!(pp_open_flags & PP_FILEOPENFLAG_READ);
  31   bool pp_write = !!(pp_open_flags & PP_FILEOPENFLAG_WRITE);
  32   bool pp_create = !!(pp_open_flags & PP_FILEOPENFLAG_CREATE);
  33   bool pp_truncate = !!(pp_open_flags & PP_FILEOPENFLAG_TRUNCATE);
  34   bool pp_exclusive = !!(pp_open_flags & PP_FILEOPENFLAG_EXCLUSIVE);
  35   bool pp_append = !!(pp_open_flags & PP_FILEOPENFLAG_APPEND);
  36
  37   if (pp_read && !(policy->*can_read)(child_id, file))
  38     return false;
  39
  40   if (pp_write && !(policy->*can_write)(child_id, file))
  41     return false;
  42
  43   // TODO(tommycli): Maybe tighten up required permission. crbug.com/284792
  44   if (pp_append && !(policy->*can_create_read_write)(child_id, file))
  45     return false;
  46
  47   if (pp_truncate && !pp_write)
  48     return false;
  49
  50   if (pp_create) {
  51     if (pp_exclusive) {
  52       return (policy->*can_create)(child_id, file);
  53     } else {
  54       // Asks for too much, but this is the only grant that allows overwrite.
  55       return (policy->*can_create_read_write)(child_id, file);
  56     }
  57   } else if (pp_truncate) {
  58     return (policy->*can_create_read_write)(child_id, file);
  59   }
  60
  61   return true;
  62 }
  63 }
  64
  65 bool CanOpenWithPepperFlags(int pp_open_flags,
  66                             int child_id,
  67                             const base::FilePath& file) {
  68   return CanOpenFileWithPepperFlags(
  69       &ChildProcessSecurityPolicyImpl::CanReadFile,
  70       &ChildProcessSecurityPolicyImpl::CanCreateReadWriteFile,
  71       &ChildProcessSecurityPolicyImpl::CanCreateReadWriteFile,
  72       &ChildProcessSecurityPolicyImpl::CanCreateReadWriteFile,
  73       pp_open_flags,
  74       child_id,
  75       file);
  76 }
  77
  78 bool CanOpenFileSystemURLWithPepperFlags(int pp_open_flags,
  79                                          int child_id,
  80                                          const storage::FileSystemURL& url) {
  81   return CanOpenFileWithPepperFlags(
  82       &ChildProcessSecurityPolicyImpl::CanReadFileSystemFile,
  83       &ChildProcessSecurityPolicyImpl::CanWriteFileSystemFile,
  84       &ChildProcessSecurityPolicyImpl::CanCreateFileSystemFile,
  85       &ChildProcessSecurityPolicyImpl::CanCreateReadWriteFileSystemFile,
  86       pp_open_flags,
  87       child_id,
  88       url);
  89 }
  90
  91 }  // namespace content