@@ -344,9 +344,9 @@ static uint64_t pauth_auth(CPUARMState *env, uint64_t ptr, uint64_t modifier,
if (unlikely(extract64(test, bot_bit, top_bit - bot_bit))) {
int error_code = (keynumber << 1) | (keynumber ^ 1);
if (param.tbi) {
- return deposit64(ptr, 53, 2, error_code);
+ return deposit64(orig_ptr, 53, 2, error_code);
} else {
- return deposit64(ptr, 61, 2, error_code);
+ return deposit64(orig_ptr, 61, 2, error_code);
}
}
return orig_ptr;
new file mode 100644
@@ -0,0 +1,61 @@
+#include <stdint.h>
+#include <assert.h>
+
+asm(".arch armv8.4-a");
+
+void do_test(uint64_t value)
+{
+ uint64_t salt1, salt2;
+ uint64_t encode, decode;
+
+ /*
+ * With TBI enabled and a 48-bit VA, there are 7 bits of auth,
+ * and so a 1/128 chance of encode = pac(value,key,salt) producing
+ * an auth for which leaves value unchanged.
+ * Iterate until we find a salt for which encode != value.
+ */
+ for (salt1 = 1; ; salt1++) {
+ asm volatile("pacda %0, %2" : "=r"(encode) : "0"(value), "r"(salt1));
+ if (encode != value) {
+ break;
+ }
+ }
+
+ /* A valid salt must produce a valid authorization. */
+ asm volatile("autda %0, %2" : "=r"(decode) : "0"(encode), "r"(salt1));
+ assert(decode == value);
+
+ /*
+ * An invalid salt usually fails authorization, but again there
+ * is a chance of choosing another salt that works.
+ * Iterate until we find another salt which does fail.
+ */
+ for (salt2 = salt1 + 1; ; salt2++) {
+ asm volatile("autda %0, %2" : "=r"(decode) : "0"(encode), "r"(salt2));
+ if (decode != value) {
+ break;
+ }
+ }
+
+ /* The VA bits, bit 55, and the TBI bits, should be unchanged. */
+ assert(((decode ^ value) & 0xff80ffffffffffffull) == 0);
+
+ /*
+ * Bits [54:53] are an error indicator based on the key used;
+ * the DA key above is keynumber 0, so error == 0b01. Otherwise
+ * bit 55 of the original is sign-extended into the rest of the auth.
+ */
+ if ((value >> 55) & 1) {
+ assert(((decode >> 48) & 0xff) == 0b10111111);
+ } else {
+ assert(((decode >> 48) & 0xff) == 0b00100000);
+ }
+}
+
+int main()
+{
+ do_test(0);
+ do_test(-1);
+ do_test(0xda004acedeadbeefull);
+ return 0;
+}
@@ -15,7 +15,7 @@ run-fcvt: fcvt
$(call run-test,$<,$(QEMU) $<, "$< on $(TARGET_NAME)")
$(call diff-out,$<,$(AARCH64_SRC)/fcvt.ref)
-AARCH64_TESTS += pauth-1
+AARCH64_TESTS += pauth-1 pauth-2
run-pauth-%: QEMU += -cpu max
TESTS:=$(AARCH64_TESTS)
The ARM pseudocode installs the error_code into the original pointer, not the encrypted pointer. The difference applies within the 7 bits of pac data; the result should be the sign extension of bit 55. Add a testcase to that effect. Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- target/arm/pauth_helper.c | 4 +- tests/tcg/aarch64/pauth-2.c | 61 +++++++++++++++++++++++++++++++ tests/tcg/aarch64/Makefile.target | 2 +- 3 files changed, 64 insertions(+), 3 deletions(-) create mode 100644 tests/tcg/aarch64/pauth-2.c -- 2.17.1