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Diffstat (limited to 'security/sandbox/linux/LinuxCapabilities.h')
-rw-r--r-- | security/sandbox/linux/LinuxCapabilities.h | 128 |
1 files changed, 0 insertions, 128 deletions
diff --git a/security/sandbox/linux/LinuxCapabilities.h b/security/sandbox/linux/LinuxCapabilities.h deleted file mode 100644 index 9d3220841..000000000 --- a/security/sandbox/linux/LinuxCapabilities.h +++ /dev/null @@ -1,128 +0,0 @@ -/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ -/* vim: set ts=8 sts=2 et sw=2 tw=80: */ -/* This Source Code Form is subject to the terms of the Mozilla Public - * License, v. 2.0. If a copy of the MPL was not distributed with this file, - * You can obtain one at http://mozilla.org/MPL/2.0/. */ - -#ifndef mozilla_LinuxCapabilities_h -#define mozilla_LinuxCapabilities_h - -#include <linux/capability.h> -#include <stdint.h> - -#include "mozilla/Assertions.h" -#include "mozilla/Attributes.h" -#include "mozilla/PodOperations.h" - -// This class is a relatively simple interface to manipulating the -// capabilities of a Linux process/thread; see the capabilities(7) man -// page for background information. - -// Unfortunately, Android's kernel headers omit some definitions -// needed for the low-level capability interface. They're part of the -// stable syscall ABI, so it's safe to include them here. -#ifndef _LINUX_CAPABILITY_VERSION_3 -#define _LINUX_CAPABILITY_VERSION_3 0x20080522 -#define _LINUX_CAPABILITY_U32S_3 2 -#endif -#ifndef CAP_TO_INDEX -#define CAP_TO_INDEX(x) ((x) >> 5) -#define CAP_TO_MASK(x) (1 << ((x) & 31)) -#endif - -namespace mozilla { - -class LinuxCapabilities final -{ -public: - // A class to represent a bit within the capability sets as an lvalue. - class BitRef { - __u32& mWord; - __u32 mMask; - friend class LinuxCapabilities; - BitRef(__u32& aWord, uint32_t aMask) : mWord(aWord), mMask(aMask) { } - BitRef(const BitRef& aBit) : mWord(aBit.mWord), mMask(aBit.mMask) { } - public: - MOZ_IMPLICIT operator bool() const { - return mWord & mMask; - } - BitRef& operator=(bool aSetTo) { - if (aSetTo) { - mWord |= mMask; - } else { - mWord &= mMask; - } - return *this; - } - }; - - // The default value is the empty set. - LinuxCapabilities() { PodArrayZero(mBits); } - - // Get the current thread's capability sets and assign them to this - // object. Returns whether it succeeded and sets errno on failure. - // Shouldn't fail unless the kernel is very old. - bool GetCurrent(); - - // Try to set the current thread's capability sets to those - // specified in this object. Returns whether it succeeded and sets - // errno on failure. - bool SetCurrentRaw() const; - - // The capability model requires that the permitted set always be a - // superset of the effective and inheritable sets. This method - // expands the permitted set as needed and then sets the current - // thread's capabilities, as described above. - bool SetCurrent() { - Normalize(); - return SetCurrentRaw(); - } - - void Normalize() { - for (size_t i = 0; i < _LINUX_CAPABILITY_U32S_3; ++i) { - mBits[i].permitted |= mBits[i].effective | mBits[i].inheritable; - } - } - - bool AnyEffective() const { - for (size_t i = 0; i < _LINUX_CAPABILITY_U32S_3; ++i) { - if (mBits[i].effective != 0) { - return true; - } - } - return false; - } - - // These three methods expose individual bits in the three - // capability sets as objects that can be used as bool lvalues. - // The argument is the capability number, as defined in - // the <linux/capability.h> header. - BitRef Effective(unsigned aCap) - { - return GenericBitRef(&__user_cap_data_struct::effective, aCap); - } - - BitRef Permitted(unsigned aCap) - { - return GenericBitRef(&__user_cap_data_struct::permitted, aCap); - } - - BitRef Inheritable(unsigned aCap) - { - return GenericBitRef(&__user_cap_data_struct::inheritable, aCap); - } - -private: - __user_cap_data_struct mBits[_LINUX_CAPABILITY_U32S_3]; - - BitRef GenericBitRef(__u32 __user_cap_data_struct::* aField, unsigned aCap) - { - // Please don't pass untrusted data as the capability number. - MOZ_ASSERT(CAP_TO_INDEX(aCap) < _LINUX_CAPABILITY_U32S_3); - return BitRef(mBits[CAP_TO_INDEX(aCap)].*aField, CAP_TO_MASK(aCap)); - } -}; - -} // namespace mozilla - -#endif // mozilla_LinuxCapabilities_h |