target/arm: Add PAuth helpers

The cryptographic internals are stubbed out for now,
but the enable and trap bits are checked.

Backports commit 0d43e1a2d29a05f7b0d5629caaff18733cbdf3bb from qemu

qemu/aarch64.h

@@ -3327,6 +3327,10 @@
 #define helper_advsimd_rinth_exact helper_advsimd_rinth_exact_aarch64
 #define helper_advsimd_sub2h helper_advsimd_sub2h_aarch64
 #define helper_advsimd_subh helper_advsimd_subh_aarch64
+#define helper_autda helper_autda_aarch64
+#define helper_autdb helper_autdb_aarch64
+#define helper_autia helper_autia_aarch64
+#define helper_autib helper_autib_aarch64
 #define helper_casp_be_parallel helper_casp_be_parallel_aarch64
 #define helper_casp_le_parallel helper_casp_le_parallel_aarch64
 #define helper_crc32_64 helper_crc32_64_aarch64
@@ -3348,6 +3352,11 @@
 #define helper_neon_ceq_f64 helper_neon_ceq_f64_aarch64
 #define helper_neon_cge_f64 helper_neon_cge_f64_aarch64
 #define helper_neon_cgt_f64 helper_neon_cgt_f64_aarch64
+#define helper_pacda helper_pacda_aarch64
+#define helper_pacdb helper_pacdb_aarch64
+#define helper_pacga helper_pacga_aarch64
+#define helper_pacia helper_pacia_aarch64
+#define helper_pacib helper_pacib_aarch64
 #define helper_paired_cmpxchg64_be helper_paired_cmpxchg64_be_aarch64
 #define helper_paired_cmpxchg64_le helper_paired_cmpxchg64_le_aarch64
 #define helper_rbit64 helper_rbit64_aarch64
@@ -4261,6 +4270,8 @@
 #define helper_vfp_cmps_a64 helper_vfp_cmps_a64_aarch64
 #define helper_vfp_mulxd helper_vfp_mulxd_aarch64
 #define helper_vfp_mulxs helper_vfp_mulxs_aarch64
+#define helper_xpacd helper_xpacd_aarch64
+#define helper_xpaci helper_xpaci_aarch64
 #define logic_imm_decode_wmask logic_imm_decode_wmask_aarch64
 #define mla_op mla_op_aarch64
 #define mls_op mls_op_aarch64

qemu/aarch64eb.h

@@ -3327,6 +3327,10 @@
 #define helper_advsimd_rinth_exact helper_advsimd_rinth_exact_aarch64eb
 #define helper_advsimd_sub2h helper_advsimd_sub2h_aarch64eb
 #define helper_advsimd_subh helper_advsimd_subh_aarch64eb
+#define helper_autda helper_autda_aarch64eb
+#define helper_autdb helper_autdb_aarch64eb
+#define helper_autia helper_autia_aarch64eb
+#define helper_autib helper_autib_aarch64eb
 #define helper_casp_be_parallel helper_casp_be_parallel_aarch64eb
 #define helper_casp_le_parallel helper_casp_le_parallel_aarch64eb
 #define helper_crc32_64 helper_crc32_64_aarch64eb
@@ -3348,6 +3352,11 @@
 #define helper_neon_ceq_f64 helper_neon_ceq_f64_aarch64eb
 #define helper_neon_cge_f64 helper_neon_cge_f64_aarch64eb
 #define helper_neon_cgt_f64 helper_neon_cgt_f64_aarch64eb
+#define helper_pacda helper_pacda_aarch64eb
+#define helper_pacdb helper_pacdb_aarch64eb
+#define helper_pacga helper_pacga_aarch64eb
+#define helper_pacia helper_pacia_aarch64eb
+#define helper_pacib helper_pacib_aarch64eb
 #define helper_paired_cmpxchg64_be helper_paired_cmpxchg64_be_aarch64eb
 #define helper_paired_cmpxchg64_le helper_paired_cmpxchg64_le_aarch64eb
 #define helper_rbit64 helper_rbit64_aarch64eb
@@ -4261,6 +4270,8 @@
 #define helper_vfp_cmps_a64 helper_vfp_cmps_a64_aarch64eb
 #define helper_vfp_mulxd helper_vfp_mulxd_aarch64eb
 #define helper_vfp_mulxs helper_vfp_mulxs_aarch64eb
+#define helper_xpacd helper_xpacd_aarch64eb
+#define helper_xpaci helper_xpaci_aarch64eb
 #define logic_imm_decode_wmask logic_imm_decode_wmask_aarch64eb
 #define mla_op mla_op_aarch64eb
 #define mls_op mls_op_aarch64eb

qemu/header_gen.py

@@ -3362,6 +3362,10 @@ aarch64_symbols = (
     'helper_advsimd_rinth_exact',
     'helper_advsimd_sub2h',
     'helper_advsimd_subh',
+    'helper_autda',
+    'helper_autdb',
+    'helper_autia',
+    'helper_autib',
     'helper_casp_be_parallel',
     'helper_casp_le_parallel',
     'helper_crc32_64',
@@ -3383,6 +3387,11 @@ aarch64_symbols = (
     'helper_neon_ceq_f64',
     'helper_neon_cge_f64',
     'helper_neon_cgt_f64',
+    'helper_pacda',
+    'helper_pacdb',
+    'helper_pacga',
+    'helper_pacia',
+    'helper_pacib',
     'helper_paired_cmpxchg64_be',
     'helper_paired_cmpxchg64_le',
     'helper_rbit64',
@@ -4296,6 +4305,8 @@ aarch64_symbols = (
     'helper_vfp_cmps_a64',
     'helper_vfp_mulxd',
     'helper_vfp_mulxs',
+    'helper_xpacd',
+    'helper_xpaci',
     'logic_imm_decode_wmask',
     'mla_op',
     'mls_op',

qemu/target/arm/Makefile.objs

@@ -2,6 +2,7 @@ obj-y += translate.o op_helper.o helper.o cpu.o
 obj-y += neon_helper.o iwmmxt_helper.o vec_helper.o
 obj-$(CONFIG_SOFTMMU) += psci.o
 obj-$(TARGET_AARCH64) += cpu64.o translate-a64.o helper-a64.o unicorn_aarch64.o
+obj-$(TARGET_AARCH64) += pauth_helper.o
 obj-$(TARGET_ARM) += unicorn_arm.o
 obj-y += crypto_helper.o
 obj-y += arm-powerctl.o

qemu/target/arm/helper-a64.h

@@ -81,3 +81,15 @@ DEF_HELPER_2(advsimd_rinth, f16, f16, ptr)
 DEF_HELPER_2(advsimd_f16tosinth, i32, f16, ptr)
 DEF_HELPER_2(advsimd_f16touinth, i32, f16, ptr)
 DEF_HELPER_2(sqrt_f16, f16, f16, ptr)
+
+DEF_HELPER_FLAGS_3(pacia, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(pacib, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(pacda, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(pacdb, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(pacga, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(autia, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(autib, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(autda, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_3(autdb, TCG_CALL_NO_WG, i64, env, i64, i64)
+DEF_HELPER_FLAGS_2(xpaci, TCG_CALL_NO_RWG_SE, i64, env, i64)
+DEF_HELPER_FLAGS_2(xpacd, TCG_CALL_NO_RWG_SE, i64, env, i64)

qemu/target/arm/internals.h

@@ -268,6 +268,7 @@ enum arm_exception_class {
     EC_CP14DTTRAP             = 0x06,
     EC_ADVSIMDFPACCESSTRAP    = 0x07,
     EC_FPIDTRAP               = 0x08,
+    EC_PACTRAP                = 0x09,
     EC_CP14RRTTRAP            = 0x0c,
     EC_ILLEGALSTATE           = 0x0e,
     EC_AA32_SVC               = 0x11,
@@ -435,6 +436,11 @@ static inline uint32_t syn_sve_access_trap(void)
     return EC_SVEACCESSTRAP << ARM_EL_EC_SHIFT;
 }
 
+static inline uint32_t syn_pactrap(void)
+{
+    return EC_PACTRAP << ARM_EL_EC_SHIFT;
+}
+
 static inline uint32_t syn_insn_abort(int same_el, int ea, int s1ptw, int fsc)
 {
     return (EC_INSNABORT << ARM_EL_EC_SHIFT) | (same_el << ARM_EL_EC_SHIFT)

qemu/target/arm/pauth_helper.c

@@ -0,0 +1,186 @@
+/*
+ * ARM v8.3-PAuth Operations
+ *
+ * Copyright (c) 2019 Linaro, Ltd.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "qemu/osdep.h"
+#include "cpu.h"
+#include "internals.h"
+#include "exec/exec-all.h"
+#include "exec/cpu_ldst.h"
+#include "exec/helper-proto.h"
+#include "tcg/tcg-gvec-desc.h"
+
+
+static uint64_t pauth_computepac(uint64_t data, uint64_t modifier,
+                                 ARMPACKey key)
+{
+    g_assert_not_reached(); /* FIXME */
+}
+
+static uint64_t pauth_addpac(CPUARMState *env, uint64_t ptr, uint64_t modifier,
+                             ARMPACKey *key, bool data)
+{
+    g_assert_not_reached(); /* FIXME */
+}
+
+static uint64_t pauth_auth(CPUARMState *env, uint64_t ptr, uint64_t modifier,
+                           ARMPACKey *key, bool data, int keynumber)
+{
+    g_assert_not_reached(); /* FIXME */
+}
+
+static uint64_t pauth_strip(CPUARMState *env, uint64_t ptr, bool data)
+{
+    g_assert_not_reached(); /* FIXME */
+}
+
+static void QEMU_NORETURN pauth_trap(CPUARMState *env, int target_el,
+                                     uintptr_t ra)
+{
+    raise_exception_ra(env, EXCP_UDEF, syn_pactrap(), target_el, ra);
+}
+
+static void pauth_check_trap(CPUARMState *env, int el, uintptr_t ra)
+{
+    if (el < 2 && arm_feature(env, ARM_FEATURE_EL2)) {
+        uint64_t hcr = arm_hcr_el2_eff(env);
+        bool trap = !(hcr & HCR_API);
+        /* FIXME: ARMv8.1-VHE: trap only applies to EL1&0 regime.  */
+        /* FIXME: ARMv8.3-NV: HCR_NV trap takes precedence for ERETA[AB].  */
+        if (trap) {
+            pauth_trap(env, 2, ra);
+        }
+    }
+    if (el < 3 && arm_feature(env, ARM_FEATURE_EL3)) {
+        if (!(env->cp15.scr_el3 & SCR_API)) {
+            pauth_trap(env, 3, ra);
+        }
+    }
+}
+
+static bool pauth_key_enabled(CPUARMState *env, int el, uint32_t bit)
+{
+    uint32_t sctlr;
+    if (el == 0) {
+        /* FIXME: ARMv8.1-VHE S2 translation regime.  */
+        sctlr = env->cp15.sctlr_el[1];
+    } else {
+        sctlr = env->cp15.sctlr_el[el];
+    }
+    return (sctlr & bit) != 0;
+}
+
+uint64_t HELPER(pacia)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnIA)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_addpac(env, x, y, &env->apia_key, false);
+}
+
+uint64_t HELPER(pacib)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnIB)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_addpac(env, x, y, &env->apib_key, false);
+}
+
+uint64_t HELPER(pacda)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnDA)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_addpac(env, x, y, &env->apda_key, true);
+}
+
+uint64_t HELPER(pacdb)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnDB)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_addpac(env, x, y, &env->apdb_key, true);
+}
+
+uint64_t HELPER(pacga)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    uint64_t pac;
+
+    pauth_check_trap(env, arm_current_el(env), GETPC());
+    pac = pauth_computepac(x, y, env->apga_key);
+
+    return pac & 0xffffffff00000000ull;
+}
+
+uint64_t HELPER(autia)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnIA)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_auth(env, x, y, &env->apia_key, false, 0);
+}
+
+uint64_t HELPER(autib)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnIB)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_auth(env, x, y, &env->apib_key, false, 1);
+}
+
+uint64_t HELPER(autda)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnDA)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_auth(env, x, y, &env->apda_key, true, 0);
+}
+
+uint64_t HELPER(autdb)(CPUARMState *env, uint64_t x, uint64_t y)
+{
+    int el = arm_current_el(env);
+    if (!pauth_key_enabled(env, el, SCTLR_EnDB)) {
+        return x;
+    }
+    pauth_check_trap(env, el, GETPC());
+    return pauth_auth(env, x, y, &env->apdb_key, true, 1);
+}
+
+uint64_t HELPER(xpaci)(CPUARMState *env, uint64_t a)
+{
+    return pauth_strip(env, a, false);
+}
+
+uint64_t HELPER(xpacd)(CPUARMState *env, uint64_t a)
+{
+    return pauth_strip(env, a, true);
+}