sandbox/linux/services/namespace_sandbox.h

   1 // Copyright 2015 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 #ifndef SANDBOX_LINUX_SERVICES_NAMESPACE_SANDBOX_H_
   6 #define SANDBOX_LINUX_SERVICES_NAMESPACE_SANDBOX_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/command_line.h"
  12 #include "base/macros.h"
  13 #include "base/process/launch.h"
  14 #include "base/process/process.h"
  15 #include "sandbox/sandbox_export.h"
  16
  17 namespace sandbox {
  18
  19 // Helper class for starting a process inside a new user, PID, and network
  20 // namespace. Before using a namespace sandbox, check for namespaces support
  21 // using Credentials::CanCreateProcessInNewUserNS.
  22 //
  23 // A typical use for "A" launching a sandboxed process "B" would be:
  24 // 1. A sets up a command line and launch options for process B.
  25 // 2. A launches B with LaunchProcess.
  26 // 3. B should be prepared to assume the role of init(1). In particular, apart
  27 //    from SIGKILL and SIGSTOP, B cannot receive any signal for which it does
  28 //    not have an explicit signal handler registered.
  29 //    If B dies, all the processes in the namespace will die.
  30 //    B can fork() and the parent can assume the role of init(1), by using
  31 //    CreateInitProcessReaper().
  32 // 4. B chroots using Credentials::MoveToNewUserNS() and
  33 //    Credentials::DropFileSystemAccess()
  34 // 5. B drops capabilities gained by entering the new user namespace with
  35 //    Credentials::DropAllCapabilities().
  36 class SANDBOX_EXPORT NamespaceSandbox {
  37  public:
  38   // Launch a new process inside its own user/PID/network namespaces (depending
  39   // on kernel support). Requires at a minimum that user namespaces are
  40   // supported (use Credentials::CanCreateProcessInNewUserNS to check this).
  41   //
  42   // pre_exec_delegate and clone_flags fields of LaunchOptions should be nullptr
  43   // and 0, respectively, since this function makes a copy of options and
  44   // overrides them.
  45   static base::Process LaunchProcess(const base::CommandLine& cmdline,
  46                                      const base::LaunchOptions& options);
  47   static base::Process LaunchProcess(const std::vector<std::string>& argv,
  48                                      const base::LaunchOptions& options);
  49
  50   // Returns whether the namespace sandbox created a new user, PID, and network
  51   // namespace. In particular, InNewUserNamespace should return true iff the
  52   // process was started via this class.
  53   static bool InNewUserNamespace();
  54   static bool InNewPidNamespace();
  55   static bool InNewNetNamespace();
  56
  57  private:
  58   DISALLOW_IMPLICIT_CONSTRUCTORS(NamespaceSandbox);
  59 };
  60
  61 }  // namespace sandbox
  62
  63 #endif  // SANDBOX_LINUX_SERVICES_NAMESPACE_SANDBOX_H_