| /* |
| * Copyright (C) 2018 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #pragma once |
| |
| namespace JSC { |
| |
| // NOTE: SecurityKind is for distancing. But caging implies distancing. So, things that have their own |
| // cages (like typed arrays) don't need to worry about the security kind. |
| enum class SecurityKind : uint8_t { |
| // The JSValueOOB security kind is for cells that contain JValues and can be accessed out-of-bounds |
| // up to minimumDistanceBetweenCellsFromDifferentOrigins. |
| // |
| // JSValues can reference cells in JSValueOOB. Therefore, JSValues can only reference cells in |
| // JSValueOOB - otherwise a Spectre OOB attack would be able to violate the rules of JSValueStrict |
| // and DangerousBits. |
| // |
| // The OOB space is the space that depends on the heap's distancing to do OOB protection. |
| JSValueOOB, |
| |
| // The JSValueStrict security kind is for cells that contain JSValues but cannot be accessed |
| // out-of-bounds. Currently, it's not essential to keep this separate from DangerousBits. We're |
| // using this to get some wiggle room for how we handle array elements. For example, we might want |
| // to allow OOB reads but not OOB writes, since JSValueStrict contains only JSValues and length fields. |
| // Using Spectre to read the length fields is not useful for attackers since they can read them anyway. |
| // So, they will only want to write to length fields, in order to confuse a subsequent bounds check. |
| // They can do that within a speculation window. However, we currently use precise index masking for |
| // this. |
| // |
| // It's illegal to use this for any subclass of JSObject, JSString, or Symbol, or any other cell |
| // that could be referenced from a JSValue. You must use poisoned pointers to point at these cells. |
| JSValueStrict, |
| |
| // The DangerousBits security kind is for cells that contain values that could be usefully type- |
| // confused with JSValue. |
| // |
| // It's illegal to use this for any subclass of JSObject, JSString, or Symbol, or any other cell |
| // that could be referenced from a JSValue. You must use poisoned pointers to point at these cells. |
| DangerousBits |
| }; |
| |
| } // namespace JSC |
| |
| namespace WTF { |
| |
| class PrintStream; |
| |
| void printInternal(PrintStream&, JSC::SecurityKind); |
| |
| } // namespace WTF |
| |