xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_ptrauth.h (revision 36b606ae6aa4b24061096ba18582e0a08ccd5dba)
15ffd83dbSDimitry Andric //===-- sanitizer_ptrauth.h -------------------------------------*- C++ -*-===//
25ffd83dbSDimitry Andric //
35ffd83dbSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
45ffd83dbSDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
55ffd83dbSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
65ffd83dbSDimitry Andric //
75ffd83dbSDimitry Andric //===----------------------------------------------------------------------===//
85ffd83dbSDimitry Andric 
95ffd83dbSDimitry Andric #ifndef SANITIZER_PTRAUTH_H
105ffd83dbSDimitry Andric #define SANITIZER_PTRAUTH_H
115ffd83dbSDimitry Andric 
12*36b606aeSDimitry Andric #if __has_feature(ptrauth_intrinsics)
135ffd83dbSDimitry Andric #  include <ptrauth.h>
14fe6060f1SDimitry Andric #elif defined(__ARM_FEATURE_PAC_DEFAULT) && !defined(__APPLE__)
15fe6060f1SDimitry Andric // On the stack the link register is protected with Pointer
16fe6060f1SDimitry Andric // Authentication Code when compiled with -mbranch-protection.
17fe6060f1SDimitry Andric // Let's stripping the PAC unconditionally because xpaclri is in
18fe6060f1SDimitry Andric // the NOP space so will do nothing when it is not enabled or not available.
19*36b606aeSDimitry Andric #  define ptrauth_strip(__value, __key) \
20*36b606aeSDimitry Andric     ({                                  \
21*36b606aeSDimitry Andric       __typeof(__value) ret;            \
22*36b606aeSDimitry Andric       asm volatile(                     \
23*36b606aeSDimitry Andric           "mov x30, %1\n\t"             \
24*36b606aeSDimitry Andric           "hint #7\n\t"                 \
25*36b606aeSDimitry Andric           "mov %0, x30\n\t"             \
26*36b606aeSDimitry Andric           "mov x30, xzr\n\t"            \
27*36b606aeSDimitry Andric           : "=r"(ret)                   \
28*36b606aeSDimitry Andric           : "r"(__value)                \
29*36b606aeSDimitry Andric           : "x30");                     \
30*36b606aeSDimitry Andric       ret;                              \
31*36b606aeSDimitry Andric     })
32fe6060f1SDimitry Andric #  define ptrauth_auth_data(__value, __old_key, __old_data) __value
33fe6060f1SDimitry Andric #  define ptrauth_string_discriminator(__string) ((int)0)
345ffd83dbSDimitry Andric #else
355ffd83dbSDimitry Andric // Copied from <ptrauth.h>
365ffd83dbSDimitry Andric #  define ptrauth_strip(__value, __key) __value
375ffd83dbSDimitry Andric #  define ptrauth_auth_data(__value, __old_key, __old_data) __value
385ffd83dbSDimitry Andric #  define ptrauth_string_discriminator(__string) ((int)0)
395ffd83dbSDimitry Andric #endif
405ffd83dbSDimitry Andric 
41fe6060f1SDimitry Andric #define STRIP_PAC_PC(pc) ((uptr)ptrauth_strip(pc, 0))
42e8d8bef9SDimitry Andric 
435ffd83dbSDimitry Andric #endif // SANITIZER_PTRAUTH_H
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