1 //===-- sanitizer_ptrauth.h -------------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef SANITIZER_PTRAUTH_H 10 #define SANITIZER_PTRAUTH_H 11 12 #if __has_feature(ptrauth_calls) 13 #include <ptrauth.h> 14 #elif defined(__ARM_FEATURE_PAC_DEFAULT) && !defined(__APPLE__) 15 inline unsigned long ptrauth_strip(void* __value, unsigned int __key) { 16 // On the stack the link register is protected with Pointer 17 // Authentication Code when compiled with -mbranch-protection. 18 // Let's stripping the PAC unconditionally because xpaclri is in 19 // the NOP space so will do nothing when it is not enabled or not available. 20 unsigned long ret; 21 asm volatile( 22 "mov x30, %1\n\t" 23 "hint #7\n\t" // xpaclri 24 "mov %0, x30\n\t" 25 : "=r"(ret) 26 : "r"(__value) 27 : "x30"); 28 return ret; 29 } 30 #define ptrauth_auth_data(__value, __old_key, __old_data) __value 31 #define ptrauth_string_discriminator(__string) ((int)0) 32 #else 33 // Copied from <ptrauth.h> 34 #define ptrauth_strip(__value, __key) __value 35 #define ptrauth_auth_data(__value, __old_key, __old_data) __value 36 #define ptrauth_string_discriminator(__string) ((int)0) 37 #endif 38 39 #define STRIP_PAC_PC(pc) ((uptr)ptrauth_strip(pc, 0)) 40 41 #endif // SANITIZER_PTRAUTH_H 42