/* SPDX-License-Identifier: GPL-2.0 */#ifndef __ASM_POINTER_AUTH_H#define __ASM_POINTER_AUTH_H #include <linux/bitops.h>#include <linux/random.h> #include <asm/cpufeature.h>#include <asm/memory.h>#include <asm/sysreg.h> #ifdef CONFIG_ARM64_PTR_AUTH/* * Each key is a 128-bit quantity which is split across a pair of 64-bit * registers (Lo and Hi). */struct ptrauth_key {	unsigned long lo, hi;}; /* * We give each process its own keys, which are shared by all threads. The keys * are inherited upon fork(), and reinitialised upon exec*(). */struct ptrauth_keys {	struct ptrauth_key apia;	struct ptrauth_key apib;	struct ptrauth_key apda;	struct ptrauth_key apdb;	struct ptrauth_key apga;}; static inline void ptrauth_keys_init(struct ptrauth_keys *keys){	if (system_supports_address_auth()) {		get_random_bytes(&keys->apia, sizeof(keys->apia));		get_random_bytes(&keys->apib, sizeof(keys->apib));		get_random_bytes(&keys->apda, sizeof(keys->apda));		get_random_bytes(&keys->apdb, sizeof(keys->apdb));	} 	if (system_supports_generic_auth())		get_random_bytes(&keys->apga, sizeof(keys->apga));} #define __ptrauth_key_install(k, v)				\do {								\	struct ptrauth_key __pki_v = (v);			\	write_sysreg_s(__pki_v.lo, SYS_ ## k ## KEYLO_EL1);	\	write_sysreg_s(__pki_v.hi, SYS_ ## k ## KEYHI_EL1);	\} while (0) static inline void ptrauth_keys_switch(struct ptrauth_keys *keys){	if (system_supports_address_auth()) {		__ptrauth_key_install(APIA, keys->apia);		__ptrauth_key_install(APIB, keys->apib);		__ptrauth_key_install(APDA, keys->apda);		__ptrauth_key_install(APDB, keys->apdb);	} 	if (system_supports_generic_auth())		__ptrauth_key_install(APGA, keys->apga);} extern int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg); /* * The EL0 pointer bits used by a pointer authentication code. * This is dependent on TBI0 being enabled, or bits 63:56 would also apply. */#define ptrauth_user_pac_mask()	GENMASK(54, vabits_user) /* Only valid for EL0 TTBR0 instruction pointers */static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr){	return ptr & ~ptrauth_user_pac_mask();} #define ptrauth_thread_init_user(tsk)					\do {									\	struct task_struct *__ptiu_tsk = (tsk);				\	ptrauth_keys_init(&__ptiu_tsk->thread.keys_user);		\	ptrauth_keys_switch(&__ptiu_tsk->thread.keys_user);		\} while (0) #define ptrauth_thread_switch(tsk)	\	ptrauth_keys_switch(&(tsk)->thread.keys_user) #else /* CONFIG_ARM64_PTR_AUTH */#define ptrauth_prctl_reset_keys(tsk, arg)	(-EINVAL)#define ptrauth_strip_insn_pac(lr)	(lr)#define ptrauth_thread_init_user(tsk)#define ptrauth_thread_switch(tsk)#endif /* CONFIG_ARM64_PTR_AUTH */ #endif /* __ASM_POINTER_AUTH_H */