target/arm: move helpers to tcg/

Signed-off-by: Claudio Fontana <cfontana@suse.de>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 515 insertions, 0 deletions

diff --git a/target/arm/tcg/pauth_helper.c b/target/arm/tcg/pauth_helper.c
new file mode 100644
index 0000000000..d0483bf051
--- /dev/null
+++ b/target/arm/tcg/pauth_helper.c
@@ -0,0 +1,515 @@
+/*
+ * 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 2.1 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"
+#include "qemu/xxhash.h"
+
+
+static uint64_t pac_cell_shuffle(uint64_t i)
+{
+    uint64_t o = 0;
+
+    o |= extract64(i, 52, 4);
+    o |= extract64(i, 24, 4) << 4;
+    o |= extract64(i, 44, 4) << 8;
+    o |= extract64(i,  0, 4) << 12;
+
+    o |= extract64(i, 28, 4) << 16;
+    o |= extract64(i, 48, 4) << 20;
+    o |= extract64(i,  4, 4) << 24;
+    o |= extract64(i, 40, 4) << 28;
+
+    o |= extract64(i, 32, 4) << 32;
+    o |= extract64(i, 12, 4) << 36;
+    o |= extract64(i, 56, 4) << 40;
+    o |= extract64(i, 20, 4) << 44;
+
+    o |= extract64(i,  8, 4) << 48;
+    o |= extract64(i, 36, 4) << 52;
+    o |= extract64(i, 16, 4) << 56;
+    o |= extract64(i, 60, 4) << 60;
+
+    return o;
+}
+
+static uint64_t pac_cell_inv_shuffle(uint64_t i)
+{
+    uint64_t o = 0;
+
+    o |= extract64(i, 12, 4);
+    o |= extract64(i, 24, 4) << 4;
+    o |= extract64(i, 48, 4) << 8;
+    o |= extract64(i, 36, 4) << 12;
+
+    o |= extract64(i, 56, 4) << 16;
+    o |= extract64(i, 44, 4) << 20;
+    o |= extract64(i,  4, 4) << 24;
+    o |= extract64(i, 16, 4) << 28;
+
+    o |= i & MAKE_64BIT_MASK(32, 4);
+    o |= extract64(i, 52, 4) << 36;
+    o |= extract64(i, 28, 4) << 40;
+    o |= extract64(i,  8, 4) << 44;
+
+    o |= extract64(i, 20, 4) << 48;
+    o |= extract64(i,  0, 4) << 52;
+    o |= extract64(i, 40, 4) << 56;
+    o |= i & MAKE_64BIT_MASK(60, 4);
+
+    return o;
+}
+
+static uint64_t pac_sub(uint64_t i)
+{
+    static const uint8_t sub[16] = {
+        0xb, 0x6, 0x8, 0xf, 0xc, 0x0, 0x9, 0xe,
+        0x3, 0x7, 0x4, 0x5, 0xd, 0x2, 0x1, 0xa,
+    };
+    uint64_t o = 0;
+    int b;
+
+    for (b = 0; b < 64; b += 4) {
+        o |= (uint64_t)sub[(i >> b) & 0xf] << b;
+    }
+    return o;
+}
+
+static uint64_t pac_inv_sub(uint64_t i)
+{
+    static const uint8_t inv_sub[16] = {
+        0x5, 0xe, 0xd, 0x8, 0xa, 0xb, 0x1, 0x9,
+        0x2, 0x6, 0xf, 0x0, 0x4, 0xc, 0x7, 0x3,
+    };
+    uint64_t o = 0;
+    int b;
+
+    for (b = 0; b < 64; b += 4) {
+        o |= (uint64_t)inv_sub[(i >> b) & 0xf] << b;
+    }
+    return o;
+}
+
+static int rot_cell(int cell, int n)
+{
+    /* 4-bit rotate left by n.  */
+    cell |= cell << 4;
+    return extract32(cell, 4 - n, 4);
+}
+
+static uint64_t pac_mult(uint64_t i)
+{
+    uint64_t o = 0;
+    int b;
+
+    for (b = 0; b < 4 * 4; b += 4) {
+        int i0, i4, i8, ic, t0, t1, t2, t3;
+
+        i0 = extract64(i, b, 4);
+        i4 = extract64(i, b + 4 * 4, 4);
+        i8 = extract64(i, b + 8 * 4, 4);
+        ic = extract64(i, b + 12 * 4, 4);
+
+        t0 = rot_cell(i8, 1) ^ rot_cell(i4, 2) ^ rot_cell(i0, 1);
+        t1 = rot_cell(ic, 1) ^ rot_cell(i4, 1) ^ rot_cell(i0, 2);
+        t2 = rot_cell(ic, 2) ^ rot_cell(i8, 1) ^ rot_cell(i0, 1);
+        t3 = rot_cell(ic, 1) ^ rot_cell(i8, 2) ^ rot_cell(i4, 1);
+
+        o |= (uint64_t)t3 << b;
+        o |= (uint64_t)t2 << (b + 4 * 4);
+        o |= (uint64_t)t1 << (b + 8 * 4);
+        o |= (uint64_t)t0 << (b + 12 * 4);
+    }
+    return o;
+}
+
+static uint64_t tweak_cell_rot(uint64_t cell)
+{
+    return (cell >> 1) | (((cell ^ (cell >> 1)) & 1) << 3);
+}
+
+static uint64_t tweak_shuffle(uint64_t i)
+{
+    uint64_t o = 0;
+
+    o |= extract64(i, 16, 4) << 0;
+    o |= extract64(i, 20, 4) << 4;
+    o |= tweak_cell_rot(extract64(i, 24, 4)) << 8;
+    o |= extract64(i, 28, 4) << 12;
+
+    o |= tweak_cell_rot(extract64(i, 44, 4)) << 16;
+    o |= extract64(i,  8, 4) << 20;
+    o |= extract64(i, 12, 4) << 24;
+    o |= tweak_cell_rot(extract64(i, 32, 4)) << 28;
+
+    o |= extract64(i, 48, 4) << 32;
+    o |= extract64(i, 52, 4) << 36;
+    o |= extract64(i, 56, 4) << 40;
+    o |= tweak_cell_rot(extract64(i, 60, 4)) << 44;
+
+    o |= tweak_cell_rot(extract64(i,  0, 4)) << 48;
+    o |= extract64(i,  4, 4) << 52;
+    o |= tweak_cell_rot(extract64(i, 40, 4)) << 56;
+    o |= tweak_cell_rot(extract64(i, 36, 4)) << 60;
+
+    return o;
+}
+
+static uint64_t tweak_cell_inv_rot(uint64_t cell)
+{
+    return ((cell << 1) & 0xf) | ((cell & 1) ^ (cell >> 3));
+}
+
+static uint64_t tweak_inv_shuffle(uint64_t i)
+{
+    uint64_t o = 0;
+
+    o |= tweak_cell_inv_rot(extract64(i, 48, 4));
+    o |= extract64(i, 52, 4) << 4;
+    o |= extract64(i, 20, 4) << 8;
+    o |= extract64(i, 24, 4) << 12;
+
+    o |= extract64(i,  0, 4) << 16;
+    o |= extract64(i,  4, 4) << 20;
+    o |= tweak_cell_inv_rot(extract64(i,  8, 4)) << 24;
+    o |= extract64(i, 12, 4) << 28;
+
+    o |= tweak_cell_inv_rot(extract64(i, 28, 4)) << 32;
+    o |= tweak_cell_inv_rot(extract64(i, 60, 4)) << 36;
+    o |= tweak_cell_inv_rot(extract64(i, 56, 4)) << 40;
+    o |= tweak_cell_inv_rot(extract64(i, 16, 4)) << 44;
+
+    o |= extract64(i, 32, 4) << 48;
+    o |= extract64(i, 36, 4) << 52;
+    o |= extract64(i, 40, 4) << 56;
+    o |= tweak_cell_inv_rot(extract64(i, 44, 4)) << 60;
+
+    return o;
+}
+
+static uint64_t pauth_computepac_architected(uint64_t data, uint64_t modifier,
+                                             ARMPACKey key)
+{
+    static const uint64_t RC[5] = {
+        0x0000000000000000ull,
+        0x13198A2E03707344ull,
+        0xA4093822299F31D0ull,
+        0x082EFA98EC4E6C89ull,
+        0x452821E638D01377ull,
+    };
+    const uint64_t alpha = 0xC0AC29B7C97C50DDull;
+    /*
+     * Note that in the ARM pseudocode, key0 contains bits <127:64>
+     * and key1 contains bits <63:0> of the 128-bit key.
+     */
+    uint64_t key0 = key.hi, key1 = key.lo;
+    uint64_t workingval, runningmod, roundkey, modk0;
+    int i;
+
+    modk0 = (key0 << 63) | ((key0 >> 1) ^ (key0 >> 63));
+    runningmod = modifier;
+    workingval = data ^ key0;
+
+    for (i = 0; i <= 4; ++i) {
+        roundkey = key1 ^ runningmod;
+        workingval ^= roundkey;
+        workingval ^= RC[i];
+        if (i > 0) {
+            workingval = pac_cell_shuffle(workingval);
+            workingval = pac_mult(workingval);
+        }
+        workingval = pac_sub(workingval);
+        runningmod = tweak_shuffle(runningmod);
+    }
+    roundkey = modk0 ^ runningmod;
+    workingval ^= roundkey;
+    workingval = pac_cell_shuffle(workingval);
+    workingval = pac_mult(workingval);
+    workingval = pac_sub(workingval);
+    workingval = pac_cell_shuffle(workingval);
+    workingval = pac_mult(workingval);
+    workingval ^= key1;
+    workingval = pac_cell_inv_shuffle(workingval);
+    workingval = pac_inv_sub(workingval);
+    workingval = pac_mult(workingval);
+    workingval = pac_cell_inv_shuffle(workingval);
+    workingval ^= key0;
+    workingval ^= runningmod;
+    for (i = 0; i <= 4; ++i) {
+        workingval = pac_inv_sub(workingval);
+        if (i < 4) {
+            workingval = pac_mult(workingval);
+            workingval = pac_cell_inv_shuffle(workingval);
+        }
+        runningmod = tweak_inv_shuffle(runningmod);
+        roundkey = key1 ^ runningmod;
+        workingval ^= RC[4 - i];
+        workingval ^= roundkey;
+        workingval ^= alpha;
+    }
+    workingval ^= modk0;
+
+    return workingval;
+}
+
+static uint64_t pauth_computepac_impdef(uint64_t data, uint64_t modifier,
+                                        ARMPACKey key)
+{
+    return qemu_xxhash64_4(data, modifier, key.lo, key.hi);
+}
+
+static uint64_t pauth_computepac(CPUARMState *env, uint64_t data,
+                                 uint64_t modifier, ARMPACKey key)
+{
+    if (cpu_isar_feature(aa64_pauth_arch, env_archcpu(env))) {
+        return pauth_computepac_architected(data, modifier, key);
+    } else {
+        return pauth_computepac_impdef(data, modifier, key);
+    }
+}
+
+static uint64_t pauth_addpac(CPUARMState *env, uint64_t ptr, uint64_t modifier,
+                             ARMPACKey *key, bool data)
+{
+    ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
+    ARMVAParameters param = aa64_va_parameters(env, ptr, mmu_idx, data);
+    uint64_t pac, ext_ptr, ext, test;
+    int bot_bit, top_bit;
+
+    /* If tagged pointers are in use, use ptr<55>, otherwise ptr<63>.  */
+    if (param.tbi) {
+        ext = sextract64(ptr, 55, 1);
+    } else {
+        ext = sextract64(ptr, 63, 1);
+    }
+
+    /* Build a pointer with known good extension bits.  */
+    top_bit = 64 - 8 * param.tbi;
+    bot_bit = 64 - param.tsz;
+    ext_ptr = deposit64(ptr, bot_bit, top_bit - bot_bit, ext);
+
+    pac = pauth_computepac(env, ext_ptr, modifier, *key);
+
+    /*
+     * Check if the ptr has good extension bits and corrupt the
+     * pointer authentication code if not.
+     */
+    test = sextract64(ptr, bot_bit, top_bit - bot_bit);
+    if (test != 0 && test != -1) {
+        /*
+         * Note that our top_bit is one greater than the pseudocode's
+         * version, hence "- 2" here.
+         */
+        pac ^= MAKE_64BIT_MASK(top_bit - 2, 1);
+    }
+
+    /*
+     * Preserve the determination between upper and lower at bit 55,
+     * and insert pointer authentication code.
+     */
+    if (param.tbi) {
+        ptr &= ~MAKE_64BIT_MASK(bot_bit, 55 - bot_bit + 1);
+        pac &= MAKE_64BIT_MASK(bot_bit, 54 - bot_bit + 1);
+    } else {
+        ptr &= MAKE_64BIT_MASK(0, bot_bit);
+        pac &= ~(MAKE_64BIT_MASK(55, 1) | MAKE_64BIT_MASK(0, bot_bit));
+    }
+    ext &= MAKE_64BIT_MASK(55, 1);
+    return pac | ext | ptr;
+}
+
+static uint64_t pauth_original_ptr(uint64_t ptr, ARMVAParameters param)
+{
+    /* Note that bit 55 is used whether or not the regime has 2 ranges. */
+    uint64_t extfield = sextract64(ptr, 55, 1);
+    int bot_pac_bit = 64 - param.tsz;
+    int top_pac_bit = 64 - 8 * param.tbi;
+
+    return deposit64(ptr, bot_pac_bit, top_pac_bit - bot_pac_bit, extfield);
+}
+
+static uint64_t pauth_auth(CPUARMState *env, uint64_t ptr, uint64_t modifier,
+                           ARMPACKey *key, bool data, int keynumber)
+{
+    ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
+    ARMVAParameters param = aa64_va_parameters(env, ptr, mmu_idx, data);
+    int bot_bit, top_bit;
+    uint64_t pac, orig_ptr, test;
+
+    orig_ptr = pauth_original_ptr(ptr, param);
+    pac = pauth_computepac(env, orig_ptr, modifier, *key);
+    bot_bit = 64 - param.tsz;
+    top_bit = 64 - 8 * param.tbi;
+
+    test = (pac ^ ptr) & ~MAKE_64BIT_MASK(55, 1);
+    if (unlikely(extract64(test, bot_bit, top_bit - bot_bit))) {
+        int error_code = (keynumber << 1) | (keynumber ^ 1);
+        if (param.tbi) {
+            return deposit64(orig_ptr, 53, 2, error_code);
+        } else {
+            return deposit64(orig_ptr, 61, 2, error_code);
+        }
+    }
+    return orig_ptr;
+}
+
+static uint64_t pauth_strip(CPUARMState *env, uint64_t ptr, bool data)
+{
+    ARMMMUIdx mmu_idx = arm_stage1_mmu_idx(env);
+    ARMVAParameters param = aa64_va_parameters(env, ptr, mmu_idx, data);
+
+    return pauth_original_ptr(ptr, param);
+}
+
+static G_NORETURN
+void 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_is_el2_enabled(env)) {
+        uint64_t hcr = arm_hcr_el2_eff(env);
+        bool trap = !(hcr & HCR_API);
+        if (el == 0) {
+            /* Trap only applies to EL1&0 regime.  */
+            trap &= (hcr & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE);
+        }
+        /* 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)
+{
+    return (arm_sctlr(env, el) & 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->keys.apia, 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->keys.apib, 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->keys.apda, 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->keys.apdb, 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(env, x, y, env->keys.apga);
+
+    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->keys.apia, 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->keys.apib, 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->keys.apda, 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->keys.apdb, 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);
+}