65 lines
2.4 KiB
C++
65 lines
2.4 KiB
C++
/*
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* Copyright (C) 2015 The Android Open Source Project
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <assert.h>
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#include <errno.h>
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#include <stddef.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/auxv.h>
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#include <sys/cdefs.h>
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#include "private/bionic_globals.h"
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#include "private/libc_logging.h"
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#include "private/KernelArgumentBlock.h"
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void __libc_init_setjmp_cookie(libc_globals* globals,
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KernelArgumentBlock& args) {
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char* random_data = reinterpret_cast<char*>(args.getauxval(AT_RANDOM));
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long value = *reinterpret_cast<long*>(random_data + 8);
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// Mask off the last bit to store the signal flag.
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globals->setjmp_cookie = value & ~1;
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}
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extern "C" __LIBC_HIDDEN__ long __bionic_setjmp_cookie_get(long sigflag) {
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if (sigflag & ~1) {
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__libc_fatal("unexpected sigflag value: %ld", sigflag);
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}
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return __libc_globals->setjmp_cookie | sigflag;
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}
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// Aborts if cookie doesn't match, returns the signal flag otherwise.
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extern "C" __LIBC_HIDDEN__ long __bionic_setjmp_cookie_check(long cookie) {
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if (__libc_globals->setjmp_cookie != (cookie & ~1)) {
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__libc_fatal("setjmp cookie mismatch");
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}
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return cookie & 1;
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}
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