2 * ARM v8.3-PAuth Operations
4 * Copyright (c) 2019 Linaro, Ltd.
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
20 #include "qemu/osdep.h"
22 #include "internals.h"
23 #include "exec/exec-all.h"
24 #include "exec/cpu_ldst.h"
25 #include "exec/helper-proto.h"
26 #include "tcg/tcg-gvec-desc.h"
29 static uint64_t pac_cell_shuffle(uint64_t i
)
33 o
|= extract64(i
, 52, 4);
34 o
|= extract64(i
, 24, 4) << 4;
35 o
|= extract64(i
, 44, 4) << 8;
36 o
|= extract64(i
, 0, 4) << 12;
38 o
|= extract64(i
, 28, 4) << 16;
39 o
|= extract64(i
, 48, 4) << 20;
40 o
|= extract64(i
, 4, 4) << 24;
41 o
|= extract64(i
, 40, 4) << 28;
43 o
|= extract64(i
, 32, 4) << 32;
44 o
|= extract64(i
, 12, 4) << 36;
45 o
|= extract64(i
, 56, 4) << 40;
46 o
|= extract64(i
, 20, 4) << 44;
48 o
|= extract64(i
, 8, 4) << 48;
49 o
|= extract64(i
, 36, 4) << 52;
50 o
|= extract64(i
, 16, 4) << 56;
51 o
|= extract64(i
, 60, 4) << 60;
56 static uint64_t pac_cell_inv_shuffle(uint64_t i
)
60 o
|= extract64(i
, 12, 4);
61 o
|= extract64(i
, 24, 4) << 4;
62 o
|= extract64(i
, 48, 4) << 8;
63 o
|= extract64(i
, 36, 4) << 12;
65 o
|= extract64(i
, 56, 4) << 16;
66 o
|= extract64(i
, 44, 4) << 20;
67 o
|= extract64(i
, 4, 4) << 24;
68 o
|= extract64(i
, 16, 4) << 28;
70 o
|= i
& MAKE_64BIT_MASK(32, 4);
71 o
|= extract64(i
, 52, 4) << 36;
72 o
|= extract64(i
, 28, 4) << 40;
73 o
|= extract64(i
, 8, 4) << 44;
75 o
|= extract64(i
, 20, 4) << 48;
76 o
|= extract64(i
, 0, 4) << 52;
77 o
|= extract64(i
, 40, 4) << 56;
78 o
|= i
& MAKE_64BIT_MASK(60, 4);
83 static uint64_t pac_sub(uint64_t i
)
85 static const uint8_t sub
[16] = {
86 0xb, 0x6, 0x8, 0xf, 0xc, 0x0, 0x9, 0xe,
87 0x3, 0x7, 0x4, 0x5, 0xd, 0x2, 0x1, 0xa,
92 for (b
= 0; b
< 64; b
+= 4) {
93 o
|= (uint64_t)sub
[(i
>> b
) & 0xf] << b
;
98 static uint64_t pac_inv_sub(uint64_t i
)
100 static const uint8_t inv_sub
[16] = {
101 0x5, 0xe, 0xd, 0x8, 0xa, 0xb, 0x1, 0x9,
102 0x2, 0x6, 0xf, 0x0, 0x4, 0xc, 0x7, 0x3,
107 for (b
= 0; b
< 64; b
+= 4) {
108 o
|= (uint64_t)inv_sub
[(i
>> b
) & 0xf] << b
;
113 static int rot_cell(int cell
, int n
)
115 /* 4-bit rotate left by n. */
117 return extract32(cell
, 4 - n
, 4);
120 static uint64_t pac_mult(uint64_t i
)
125 for (b
= 0; b
< 4 * 4; b
+= 4) {
126 int i0
, i4
, i8
, ic
, t0
, t1
, t2
, t3
;
128 i0
= extract64(i
, b
, 4);
129 i4
= extract64(i
, b
+ 4 * 4, 4);
130 i8
= extract64(i
, b
+ 8 * 4, 4);
131 ic
= extract64(i
, b
+ 12 * 4, 4);
133 t0
= rot_cell(i8
, 1) ^ rot_cell(i4
, 2) ^ rot_cell(i0
, 1);
134 t1
= rot_cell(ic
, 1) ^ rot_cell(i4
, 1) ^ rot_cell(i0
, 2);
135 t2
= rot_cell(ic
, 2) ^ rot_cell(i8
, 1) ^ rot_cell(i0
, 1);
136 t3
= rot_cell(ic
, 1) ^ rot_cell(i8
, 2) ^ rot_cell(i4
, 1);
138 o
|= (uint64_t)t3
<< b
;
139 o
|= (uint64_t)t2
<< (b
+ 4 * 4);
140 o
|= (uint64_t)t1
<< (b
+ 8 * 4);
141 o
|= (uint64_t)t0
<< (b
+ 12 * 4);
146 static uint64_t tweak_cell_rot(uint64_t cell
)
148 return (cell
>> 1) | (((cell
^ (cell
>> 1)) & 1) << 3);
151 static uint64_t tweak_shuffle(uint64_t i
)
155 o
|= extract64(i
, 16, 4) << 0;
156 o
|= extract64(i
, 20, 4) << 4;
157 o
|= tweak_cell_rot(extract64(i
, 24, 4)) << 8;
158 o
|= extract64(i
, 28, 4) << 12;
160 o
|= tweak_cell_rot(extract64(i
, 44, 4)) << 16;
161 o
|= extract64(i
, 8, 4) << 20;
162 o
|= extract64(i
, 12, 4) << 24;
163 o
|= tweak_cell_rot(extract64(i
, 32, 4)) << 28;
165 o
|= extract64(i
, 48, 4) << 32;
166 o
|= extract64(i
, 52, 4) << 36;
167 o
|= extract64(i
, 56, 4) << 40;
168 o
|= tweak_cell_rot(extract64(i
, 60, 4)) << 44;
170 o
|= tweak_cell_rot(extract64(i
, 0, 4)) << 48;
171 o
|= extract64(i
, 4, 4) << 52;
172 o
|= tweak_cell_rot(extract64(i
, 40, 4)) << 56;
173 o
|= tweak_cell_rot(extract64(i
, 36, 4)) << 60;
178 static uint64_t tweak_cell_inv_rot(uint64_t cell
)
180 return ((cell
<< 1) & 0xf) | ((cell
& 1) ^ (cell
>> 3));
183 static uint64_t tweak_inv_shuffle(uint64_t i
)
187 o
|= tweak_cell_inv_rot(extract64(i
, 48, 4));
188 o
|= extract64(i
, 52, 4) << 4;
189 o
|= extract64(i
, 20, 4) << 8;
190 o
|= extract64(i
, 24, 4) << 12;
192 o
|= extract64(i
, 0, 4) << 16;
193 o
|= extract64(i
, 4, 4) << 20;
194 o
|= tweak_cell_inv_rot(extract64(i
, 8, 4)) << 24;
195 o
|= extract64(i
, 12, 4) << 28;
197 o
|= tweak_cell_inv_rot(extract64(i
, 28, 4)) << 32;
198 o
|= tweak_cell_inv_rot(extract64(i
, 60, 4)) << 36;
199 o
|= tweak_cell_inv_rot(extract64(i
, 56, 4)) << 40;
200 o
|= tweak_cell_inv_rot(extract64(i
, 16, 4)) << 44;
202 o
|= extract64(i
, 32, 4) << 48;
203 o
|= extract64(i
, 36, 4) << 52;
204 o
|= extract64(i
, 40, 4) << 56;
205 o
|= tweak_cell_inv_rot(extract64(i
, 44, 4)) << 60;
210 static uint64_t pauth_computepac(uint64_t data
, uint64_t modifier
,
213 static const uint64_t RC
[5] = {
214 0x0000000000000000ull
,
215 0x13198A2E03707344ull
,
216 0xA4093822299F31D0ull
,
217 0x082EFA98EC4E6C89ull
,
218 0x452821E638D01377ull
,
220 const uint64_t alpha
= 0xC0AC29B7C97C50DDull
;
222 * Note that in the ARM pseudocode, key0 contains bits <127:64>
223 * and key1 contains bits <63:0> of the 128-bit key.
225 uint64_t key0
= key
.hi
, key1
= key
.lo
;
226 uint64_t workingval
, runningmod
, roundkey
, modk0
;
229 modk0
= (key0
<< 63) | ((key0
>> 1) ^ (key0
>> 63));
230 runningmod
= modifier
;
231 workingval
= data
^ key0
;
233 for (i
= 0; i
<= 4; ++i
) {
234 roundkey
= key1
^ runningmod
;
235 workingval
^= roundkey
;
238 workingval
= pac_cell_shuffle(workingval
);
239 workingval
= pac_mult(workingval
);
241 workingval
= pac_sub(workingval
);
242 runningmod
= tweak_shuffle(runningmod
);
244 roundkey
= modk0
^ runningmod
;
245 workingval
^= roundkey
;
246 workingval
= pac_cell_shuffle(workingval
);
247 workingval
= pac_mult(workingval
);
248 workingval
= pac_sub(workingval
);
249 workingval
= pac_cell_shuffle(workingval
);
250 workingval
= pac_mult(workingval
);
252 workingval
= pac_cell_inv_shuffle(workingval
);
253 workingval
= pac_inv_sub(workingval
);
254 workingval
= pac_mult(workingval
);
255 workingval
= pac_cell_inv_shuffle(workingval
);
257 workingval
^= runningmod
;
258 for (i
= 0; i
<= 4; ++i
) {
259 workingval
= pac_inv_sub(workingval
);
261 workingval
= pac_mult(workingval
);
262 workingval
= pac_cell_inv_shuffle(workingval
);
264 runningmod
= tweak_inv_shuffle(runningmod
);
265 roundkey
= key1
^ runningmod
;
266 workingval
^= RC
[4 - i
];
267 workingval
^= roundkey
;
275 static uint64_t pauth_addpac(CPUARMState
*env
, uint64_t ptr
, uint64_t modifier
,
276 ARMPACKey
*key
, bool data
)
278 ARMMMUIdx mmu_idx
= arm_stage1_mmu_idx(env
);
279 ARMVAParameters param
= aa64_va_parameters(env
, ptr
, mmu_idx
, data
);
280 uint64_t pac
, ext_ptr
, ext
, test
;
281 int bot_bit
, top_bit
;
283 /* If tagged pointers are in use, use ptr<55>, otherwise ptr<63>. */
285 ext
= sextract64(ptr
, 55, 1);
287 ext
= sextract64(ptr
, 63, 1);
290 /* Build a pointer with known good extension bits. */
291 top_bit
= 64 - 8 * param
.tbi
;
292 bot_bit
= 64 - param
.tsz
;
293 ext_ptr
= deposit64(ptr
, bot_bit
, top_bit
- bot_bit
, ext
);
295 pac
= pauth_computepac(ext_ptr
, modifier
, *key
);
298 * Check if the ptr has good extension bits and corrupt the
299 * pointer authentication code if not.
301 test
= sextract64(ptr
, bot_bit
, top_bit
- bot_bit
);
302 if (test
!= 0 && test
!= -1) {
304 * Note that our top_bit is one greater than the pseudocode's
305 * version, hence "- 2" here.
307 pac
^= MAKE_64BIT_MASK(top_bit
- 2, 1);
311 * Preserve the determination between upper and lower at bit 55,
312 * and insert pointer authentication code.
315 ptr
&= ~MAKE_64BIT_MASK(bot_bit
, 55 - bot_bit
+ 1);
316 pac
&= MAKE_64BIT_MASK(bot_bit
, 54 - bot_bit
+ 1);
318 ptr
&= MAKE_64BIT_MASK(0, bot_bit
);
319 pac
&= ~(MAKE_64BIT_MASK(55, 1) | MAKE_64BIT_MASK(0, bot_bit
));
321 ext
&= MAKE_64BIT_MASK(55, 1);
322 return pac
| ext
| ptr
;
325 static uint64_t pauth_original_ptr(uint64_t ptr
, ARMVAParameters param
)
327 /* Note that bit 55 is used whether or not the regime has 2 ranges. */
328 uint64_t extfield
= sextract64(ptr
, 55, 1);
329 int bot_pac_bit
= 64 - param
.tsz
;
330 int top_pac_bit
= 64 - 8 * param
.tbi
;
332 return deposit64(ptr
, bot_pac_bit
, top_pac_bit
- bot_pac_bit
, extfield
);
335 static uint64_t pauth_auth(CPUARMState
*env
, uint64_t ptr
, uint64_t modifier
,
336 ARMPACKey
*key
, bool data
, int keynumber
)
338 ARMMMUIdx mmu_idx
= arm_stage1_mmu_idx(env
);
339 ARMVAParameters param
= aa64_va_parameters(env
, ptr
, mmu_idx
, data
);
340 int bot_bit
, top_bit
;
341 uint64_t pac
, orig_ptr
, test
;
343 orig_ptr
= pauth_original_ptr(ptr
, param
);
344 pac
= pauth_computepac(orig_ptr
, modifier
, *key
);
345 bot_bit
= 64 - param
.tsz
;
346 top_bit
= 64 - 8 * param
.tbi
;
348 test
= (pac
^ ptr
) & ~MAKE_64BIT_MASK(55, 1);
349 if (unlikely(extract64(test
, bot_bit
, top_bit
- bot_bit
))) {
350 int error_code
= (keynumber
<< 1) | (keynumber
^ 1);
352 return deposit64(orig_ptr
, 53, 2, error_code
);
354 return deposit64(orig_ptr
, 61, 2, error_code
);
360 static uint64_t pauth_strip(CPUARMState
*env
, uint64_t ptr
, bool data
)
362 ARMMMUIdx mmu_idx
= arm_stage1_mmu_idx(env
);
363 ARMVAParameters param
= aa64_va_parameters(env
, ptr
, mmu_idx
, data
);
365 return pauth_original_ptr(ptr
, param
);
368 static void QEMU_NORETURN
pauth_trap(CPUARMState
*env
, int target_el
,
371 raise_exception_ra(env
, EXCP_UDEF
, syn_pactrap(), target_el
, ra
);
374 static void pauth_check_trap(CPUARMState
*env
, int el
, uintptr_t ra
)
376 if (el
< 2 && arm_feature(env
, ARM_FEATURE_EL2
)) {
377 uint64_t hcr
= arm_hcr_el2_eff(env
);
378 bool trap
= !(hcr
& HCR_API
);
380 /* Trap only applies to EL1&0 regime. */
381 trap
&= (hcr
& (HCR_E2H
| HCR_TGE
)) != (HCR_E2H
| HCR_TGE
);
383 /* FIXME: ARMv8.3-NV: HCR_NV trap takes precedence for ERETA[AB]. */
385 pauth_trap(env
, 2, ra
);
388 if (el
< 3 && arm_feature(env
, ARM_FEATURE_EL3
)) {
389 if (!(env
->cp15
.scr_el3
& SCR_API
)) {
390 pauth_trap(env
, 3, ra
);
395 static bool pauth_key_enabled(CPUARMState
*env
, int el
, uint32_t bit
)
397 return (arm_sctlr(env
, el
) & bit
) != 0;
400 uint64_t HELPER(pacia
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
402 int el
= arm_current_el(env
);
403 if (!pauth_key_enabled(env
, el
, SCTLR_EnIA
)) {
406 pauth_check_trap(env
, el
, GETPC());
407 return pauth_addpac(env
, x
, y
, &env
->keys
.apia
, false);
410 uint64_t HELPER(pacib
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
412 int el
= arm_current_el(env
);
413 if (!pauth_key_enabled(env
, el
, SCTLR_EnIB
)) {
416 pauth_check_trap(env
, el
, GETPC());
417 return pauth_addpac(env
, x
, y
, &env
->keys
.apib
, false);
420 uint64_t HELPER(pacda
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
422 int el
= arm_current_el(env
);
423 if (!pauth_key_enabled(env
, el
, SCTLR_EnDA
)) {
426 pauth_check_trap(env
, el
, GETPC());
427 return pauth_addpac(env
, x
, y
, &env
->keys
.apda
, true);
430 uint64_t HELPER(pacdb
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
432 int el
= arm_current_el(env
);
433 if (!pauth_key_enabled(env
, el
, SCTLR_EnDB
)) {
436 pauth_check_trap(env
, el
, GETPC());
437 return pauth_addpac(env
, x
, y
, &env
->keys
.apdb
, true);
440 uint64_t HELPER(pacga
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
444 pauth_check_trap(env
, arm_current_el(env
), GETPC());
445 pac
= pauth_computepac(x
, y
, env
->keys
.apga
);
447 return pac
& 0xffffffff00000000ull
;
450 uint64_t HELPER(autia
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
452 int el
= arm_current_el(env
);
453 if (!pauth_key_enabled(env
, el
, SCTLR_EnIA
)) {
456 pauth_check_trap(env
, el
, GETPC());
457 return pauth_auth(env
, x
, y
, &env
->keys
.apia
, false, 0);
460 uint64_t HELPER(autib
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
462 int el
= arm_current_el(env
);
463 if (!pauth_key_enabled(env
, el
, SCTLR_EnIB
)) {
466 pauth_check_trap(env
, el
, GETPC());
467 return pauth_auth(env
, x
, y
, &env
->keys
.apib
, false, 1);
470 uint64_t HELPER(autda
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
472 int el
= arm_current_el(env
);
473 if (!pauth_key_enabled(env
, el
, SCTLR_EnDA
)) {
476 pauth_check_trap(env
, el
, GETPC());
477 return pauth_auth(env
, x
, y
, &env
->keys
.apda
, true, 0);
480 uint64_t HELPER(autdb
)(CPUARMState
*env
, uint64_t x
, uint64_t y
)
482 int el
= arm_current_el(env
);
483 if (!pauth_key_enabled(env
, el
, SCTLR_EnDB
)) {
486 pauth_check_trap(env
, el
, GETPC());
487 return pauth_auth(env
, x
, y
, &env
->keys
.apdb
, true, 1);
490 uint64_t HELPER(xpaci
)(CPUARMState
*env
, uint64_t a
)
492 return pauth_strip(env
, a
, false);
495 uint64_t HELPER(xpacd
)(CPUARMState
*env
, uint64_t a
)
497 return pauth_strip(env
, a
, true);