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// 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.
#ifndef CONTENT_COMMON_SANDBOX_LINUX_H_
#define CONTENT_COMMON_SANDBOX_LINUX_H_
#include <string>
#include "base/basictypes.h"
#include "base/memory/scoped_ptr.h"
#include "content/public/common/sandbox_linux.h"
template <typename T> struct DefaultSingletonTraits;
namespace sandbox { class SetuidSandboxClient; }
namespace content {
// A singleton class to represent and change our sandboxing state for the
// three main Linux sandboxes.
class LinuxSandbox {
public:
// This is a list of sandbox IPC methods which the renderer may send to the
// sandbox host. See http://code.google.com/p/chromium/wiki/LinuxSandboxIPC
// This isn't the full list, values < 32 are reserved for methods called from
// Skia.
enum LinuxSandboxIPCMethods {
METHOD_GET_FONT_FAMILY_FOR_CHARS = 32,
METHOD_LOCALTIME = 33,
METHOD_GET_CHILD_WITH_INODE = 34,
METHOD_GET_STYLE_FOR_STRIKE = 35,
METHOD_MAKE_SHARED_MEMORY_SEGMENT = 36,
METHOD_MATCH_WITH_FALLBACK = 37,
};
// Get our singleton instance.
static LinuxSandbox* GetInstance();
// Do some initialization that can only be done before any of the sandboxes
// is enabled.
//
// There are two versions of this function. One takes a process_type
// as an argument, the other doesn't.
// It may be necessary to call PreinitializeSandboxBegin before knowing the
// process type (this is for instance the case with the Zygote).
// In that case, it is crucial that PreinitializeSandboxFinish() gets
// called for every child process.
// TODO(markus, jln) we know this is not always done at the moment
// (crbug.com/139877).
void PreinitializeSandbox(const std::string& process_type);
// These should be called together.
void PreinitializeSandboxBegin();
void PreinitializeSandboxFinish(const std::string& process_type);
// Returns the Status of the sandbox. Can only be queried if we went through
// PreinitializeSandbox() or PreinitializeSandboxBegin(). This is a bitmask
// and uses the constants defined in "enum LinuxSandboxStatus".
// Since we need to provide the status before the sandboxes are actually
// started, this returns what will actually happen once the various Start*
// functions are called from inside a renderer.
int GetStatus() const;
// Is the current process single threaded?
bool IsSingleThreaded() const;
// Did we start Seccomp BPF?
bool seccomp_bpf_started() const;
// Simple accessor for our instance of the setuid sandbox. Will never return
// NULL.
// There is no StartSetuidSandbox(), the SetuidSandboxClient instance should
// be used directly.
sandbox::SetuidSandboxClient* setuid_sandbox_client() const;
// Check the policy and eventually start the seccomp-legacy sandbox.
bool StartSeccompLegacy(const std::string& process_type);
// Check the policy and eventually start the seccomp-bpf sandbox.
bool StartSeccompBpf(const std::string& process_type);
// Limit the address space of the current process (and its children).
// to make some vulnerabilities harder to exploit.
bool LimitAddressSpace(const std::string& process_type);
private:
friend struct DefaultSingletonTraits<LinuxSandbox>;
// We must have been pre_initialized_ before using either of these.
bool seccomp_legacy_supported() const;
bool seccomp_bpf_supported() const;
int proc_fd_;
bool seccomp_bpf_started_;
// Have we been through PreinitializeSandbox or PreinitializeSandboxBegin?
bool pre_initialized_;
bool seccomp_legacy_supported_; // Accurate if pre_initialized_.
bool seccomp_bpf_supported_; // Accurate if pre_initialized_.
scoped_ptr<sandbox::SetuidSandboxClient> setuid_sandbox_client_;
~LinuxSandbox();
DISALLOW_IMPLICIT_CONSTRUCTORS(LinuxSandbox);
};
} // namespace content
#endif // CONTENT_COMMON_SANDBOX_LINUX_H_
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