/* * Copyright (c) 2019 Apple Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ #ifndef _ARM64_PAC_ASM_H_ #define _ARM64_PAC_ASM_H_ #ifndef __ASSEMBLER__ #error "This header should only be used in .s files" #endif #include <pexpert/arm64/board_config.h> #include <arm64/proc_reg.h> #if HAS_PARAVIRTUALIZED_PAC #include "smccc_asm.h" #endif #include "assym.s" #if defined(HAS_APPLE_PAC) /* BEGIN IGNORE CODESTYLE */ /** * REPROGRAM_JOP_KEYS * * Loads a userspace process's JOP key (task->jop_pid) into the CPU, and * updates current_cpu_datap()->jop_key accordingly. This reprogramming process * is skipped whenever the "new" JOP key has already been loaded into the CPU. * * skip_label - branch to this label if new_jop_key is already loaded into CPU * new_jop_key - process's jop_pid * cpudatap - current cpu_data_t * * tmp - scratch register */ .macro REPROGRAM_JOP_KEYS skip_label, new_jop_key, cpudatap, tmp ldr \tmp, [\cpudatap, CPU_JOP_KEY] cmp \new_jop_key, \tmp b.eq \skip_label SET_JOP_KEY_REGISTERS \new_jop_key, \tmp str \new_jop_key, [\cpudatap, CPU_JOP_KEY] .endmacro /** * REPROGRAM_ROP_KEYS * * Loads a userspace process's ROP key (task->rop_pid) into the CPU, and * updates current_cpu_datap()->rop_key accordingly. This reprogramming process * is skipped whenever the "new" ROP key has already been loaded into the CPU. * * skip_label - branch to this label if new_rop_key is already loaded into CPU * new_rop_key - process's rop_pid * cpudatap - current cpu_data_t * * tmp - scratch register */ .macro REPROGRAM_ROP_KEYS skip_label, new_rop_key, cpudatap, tmp ldr \tmp, [\cpudatap, CPU_ROP_KEY] cmp \new_rop_key, \tmp b.eq \skip_label SET_ROP_KEY_REGISTERS \new_rop_key, \tmp str \new_rop_key, [\cpudatap, CPU_ROP_KEY] .endmacro /** * SET_JOP_KEY_REGISTERS * * Unconditionally loads a userspace process's JOP key (task->jop_pid) into the * CPU. The caller is responsible for updating current_cpu_datap()->jop_key as * needed. * * new_jop_key - process's jop_pid * tmp - scratch register */ .macro SET_JOP_KEY_REGISTERS new_jop_key, tmp #if HAS_PARAVIRTUALIZED_PAC SAVE_SMCCC_CLOBBERED_REGISTERS /* * We're deliberately calling PAC_SET_EL0_DIVERSIFIER here, even though the * EL0 diversifier affects both A (JOP) and B (ROP) keys. We don't want * SET_JOP_KEY_REGISTERS to have an impact on the EL1 A key state, since * these are the keys the kernel uses to sign pointers on the heap. * * Using new_jop_key as the EL0 diversifer has the same net effect of giving * userspace its own set of JOP keys, but doesn't affect EL1 A key state. */ MOV64 x0, VMAPPLE_PAC_SET_EL0_DIVERSIFIER mov x1, \new_jop_key hvc #0 LOAD_SMCCC_CLOBBERED_REGISTERS #endif /* HAS_PARAVIRTUALIZED_PAC */ .endmacro /** * SET_ROP_KEY_REGISTERS * * Unconditionally loads a userspace process's ROP key (task->rop_pid) into the * CPU. The caller is responsible for updating current_cpu_datap()->rop_key as * needed. * * new_rop_key - process's rop_pid * tmp - scratch register */ .macro SET_ROP_KEY_REGISTERS new_rop_key, tmp #if HAS_PARAVIRTUALIZED_PAC SAVE_SMCCC_CLOBBERED_REGISTERS MOV64 x0, VMAPPLE_PAC_SET_B_KEYS mov x1, \new_rop_key hvc #0 LOAD_SMCCC_CLOBBERED_REGISTERS #endif /* HAS_PARAVIRTUALIZED_PAC */ .endmacro /* END IGNORE CODESTYLE */ #endif /* defined(HAS_APPLE_PAC) */ #endif /* _ARM64_PAC_ASM_H_ */ /* vim: set ts=4 ft=asm: */