153 lines
4.5 KiB
C
153 lines
4.5 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
#ifndef __ASM_POINTER_AUTH_H
|
|
#define __ASM_POINTER_AUTH_H
|
|
|
|
#include <linux/bitops.h>
|
|
#include <linux/prctl.h>
|
|
#include <linux/random.h>
|
|
|
|
#include <asm/cpufeature.h>
|
|
#include <asm/memory.h>
|
|
#include <asm/sysreg.h>
|
|
|
|
#define PR_PAC_ENABLED_KEYS_MASK \
|
|
(PR_PAC_APIAKEY | PR_PAC_APIBKEY | PR_PAC_APDAKEY | PR_PAC_APDBKEY)
|
|
|
|
#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_user {
|
|
struct ptrauth_key apia;
|
|
struct ptrauth_key apib;
|
|
struct ptrauth_key apda;
|
|
struct ptrauth_key apdb;
|
|
struct ptrauth_key apga;
|
|
};
|
|
|
|
#define __ptrauth_key_install_nosync(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)
|
|
|
|
#ifdef CONFIG_ARM64_PTR_AUTH_KERNEL
|
|
|
|
struct ptrauth_keys_kernel {
|
|
struct ptrauth_key apia;
|
|
};
|
|
|
|
static __always_inline void ptrauth_keys_init_kernel(struct ptrauth_keys_kernel *keys)
|
|
{
|
|
if (system_supports_address_auth())
|
|
get_random_bytes(&keys->apia, sizeof(keys->apia));
|
|
}
|
|
|
|
static __always_inline void ptrauth_keys_switch_kernel(struct ptrauth_keys_kernel *keys)
|
|
{
|
|
if (!system_supports_address_auth())
|
|
return;
|
|
|
|
__ptrauth_key_install_nosync(APIA, keys->apia);
|
|
isb();
|
|
}
|
|
|
|
#endif /* CONFIG_ARM64_PTR_AUTH_KERNEL */
|
|
|
|
static inline void ptrauth_keys_install_user(struct ptrauth_keys_user *keys)
|
|
{
|
|
if (system_supports_address_auth()) {
|
|
__ptrauth_key_install_nosync(APIB, keys->apib);
|
|
__ptrauth_key_install_nosync(APDA, keys->apda);
|
|
__ptrauth_key_install_nosync(APDB, keys->apdb);
|
|
}
|
|
|
|
if (system_supports_generic_auth())
|
|
__ptrauth_key_install_nosync(APGA, keys->apga);
|
|
}
|
|
|
|
static inline void ptrauth_keys_init_user(struct ptrauth_keys_user *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));
|
|
|
|
ptrauth_keys_install_user(keys);
|
|
}
|
|
|
|
extern int ptrauth_prctl_reset_keys(struct task_struct *tsk, unsigned long arg);
|
|
|
|
extern int ptrauth_set_enabled_keys(struct task_struct *tsk, unsigned long keys,
|
|
unsigned long enabled);
|
|
extern int ptrauth_get_enabled_keys(struct task_struct *tsk);
|
|
|
|
static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr)
|
|
{
|
|
return ptrauth_clear_pac(ptr);
|
|
}
|
|
|
|
static __always_inline void ptrauth_enable(void)
|
|
{
|
|
if (!system_supports_address_auth())
|
|
return;
|
|
sysreg_clear_set(sctlr_el1, 0, (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB |
|
|
SCTLR_ELx_ENDA | SCTLR_ELx_ENDB));
|
|
isb();
|
|
}
|
|
|
|
#define ptrauth_suspend_exit() \
|
|
ptrauth_keys_install_user(¤t->thread.keys_user)
|
|
|
|
#define ptrauth_thread_init_user() \
|
|
do { \
|
|
ptrauth_keys_init_user(¤t->thread.keys_user); \
|
|
\
|
|
/* enable all keys */ \
|
|
if (system_supports_address_auth()) \
|
|
ptrauth_set_enabled_keys(current, \
|
|
PR_PAC_ENABLED_KEYS_MASK, \
|
|
PR_PAC_ENABLED_KEYS_MASK); \
|
|
} while (0)
|
|
|
|
#define ptrauth_thread_switch_user(tsk) \
|
|
ptrauth_keys_install_user(&(tsk)->thread.keys_user)
|
|
|
|
#else /* CONFIG_ARM64_PTR_AUTH */
|
|
#define ptrauth_enable()
|
|
#define ptrauth_prctl_reset_keys(tsk, arg) (-EINVAL)
|
|
#define ptrauth_set_enabled_keys(tsk, keys, enabled) (-EINVAL)
|
|
#define ptrauth_get_enabled_keys(tsk) (-EINVAL)
|
|
#define ptrauth_strip_insn_pac(lr) (lr)
|
|
#define ptrauth_suspend_exit()
|
|
#define ptrauth_thread_init_user()
|
|
#define ptrauth_thread_switch_user(tsk)
|
|
#endif /* CONFIG_ARM64_PTR_AUTH */
|
|
|
|
#ifdef CONFIG_ARM64_PTR_AUTH_KERNEL
|
|
#define ptrauth_thread_init_kernel(tsk) \
|
|
ptrauth_keys_init_kernel(&(tsk)->thread.keys_kernel)
|
|
#define ptrauth_thread_switch_kernel(tsk) \
|
|
ptrauth_keys_switch_kernel(&(tsk)->thread.keys_kernel)
|
|
#else
|
|
#define ptrauth_thread_init_kernel(tsk)
|
|
#define ptrauth_thread_switch_kernel(tsk)
|
|
#endif /* CONFIG_ARM64_PTR_AUTH_KERNEL */
|
|
|
|
#endif /* __ASM_POINTER_AUTH_H */
|