sandbox/win/src/handle_policy.cc

   1 // Copyright (c) 2012 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 "sandbox/win/src/handle_policy.h"
   6
   7 #include <string>
   8
   9 #include "base/win/scoped_handle.h"
  10 #include "sandbox/win/src/broker_services.h"
  11 #include "sandbox/win/src/ipc_tags.h"
  12 #include "sandbox/win/src/policy_engine_opcodes.h"
  13 #include "sandbox/win/src/policy_params.h"
  14 #include "sandbox/win/src/sandbox_types.h"
  15 #include "sandbox/win/src/sandbox_utils.h"
  16
  17 namespace sandbox {
  18
  19 bool HandlePolicy::GenerateRules(const wchar_t* type_name,
  20                                  TargetPolicy::Semantics semantics,
  21                                  LowLevelPolicy* policy) {
  22   PolicyRule duplicate_rule(ASK_BROKER);
  23
  24   switch (semantics) {
  25     case TargetPolicy::HANDLES_DUP_ANY: {
  26       if (!duplicate_rule.AddNumberMatch(IF_NOT, HandleTarget::TARGET,
  27                                          ::GetCurrentProcessId(), EQUAL)) {
  28         return false;
  29       }
  30       break;
  31     }
  32
  33     case TargetPolicy::HANDLES_DUP_BROKER: {
  34       if (!duplicate_rule.AddNumberMatch(IF, HandleTarget::TARGET,
  35                                          ::GetCurrentProcessId(), EQUAL)) {
  36         return false;
  37       }
  38       break;
  39     }
  40
  41     default:
  42      return false;
  43   }
  44   if (!duplicate_rule.AddStringMatch(IF, HandleTarget::NAME, type_name,
  45                                      CASE_INSENSITIVE)) {
  46     return false;
  47   }
  48   if (!policy->AddRule(IPC_DUPLICATEHANDLEPROXY_TAG, &duplicate_rule)) {
  49     return false;
  50   }
  51   return true;
  52 }
  53
  54 DWORD HandlePolicy::DuplicateHandleProxyAction(EvalResult eval_result,
  55                                                HANDLE source_handle,
  56                                                DWORD target_process_id,
  57                                                HANDLE* target_handle,
  58                                                DWORD desired_access,
  59                                                DWORD options) {
  60   // The only action supported is ASK_BROKER which means duplicate the handle.
  61   if (ASK_BROKER != eval_result) {
  62     return ERROR_ACCESS_DENIED;
  63   }
  64
  65   base::win::ScopedHandle remote_target_process;
  66   if (target_process_id != ::GetCurrentProcessId()) {
  67     // Sandboxed children are dynamic, so we check that manually.
  68     if (!BrokerServicesBase::GetInstance()->IsActiveTarget(target_process_id)) {
  69       return ERROR_ACCESS_DENIED;
  70     }
  71
  72     remote_target_process.Set(::OpenProcess(PROCESS_DUP_HANDLE, FALSE,
  73                                             target_process_id));
  74     if (!remote_target_process.IsValid())
  75       return ::GetLastError();
  76   }
  77
  78   // If the policy didn't block us and we have no valid target, then the broker
  79   // (this process) is the valid target.
  80   HANDLE target_process = remote_target_process.IsValid() ?
  81                           remote_target_process.Get() : ::GetCurrentProcess();
  82   if (!::DuplicateHandle(::GetCurrentProcess(), source_handle, target_process,
  83                          target_handle, desired_access, FALSE,
  84                          options)) {
  85     return ::GetLastError();
  86   }
  87
  88   return ERROR_SUCCESS;
  89 }
  90
  91 }  // namespace sandbox
  92