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#include <stdint.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include "pauth.h"
#define TESTS 1000
int main()
{
char base[TESTS];
int i, count = 0;
float perc;
int pac_feature = get_pac_feature();
/*
* Exit if no PAuth or FEAT_FPAC, which will SIGILL on AUTIA failure
* rather than return an error for us to check below.
*/
if (pac_feature == 0 || pac_feature >= 4) {
return 0;
}
for (i = 0; i < TESTS; i++) {
uintptr_t in, x, y;
in = i + (uintptr_t) base;
asm("mov %0, %[in]\n\t"
"pacia %0, sp\n\t"
"eor %0, %0, #4\n\t" /* corrupt single bit */
"mov %1, %0\n\t"
"autia %1, sp\n\t" /* validate corrupted pointer */
"xpaci %0\n\t" /* strip pac from corrupted pointer */
: /* out */ "=r"(x), "=r"(y)
: /* in */ [in] "r" (in)
: /* clobbers */);
/*
* Once stripped, the corrupted pointer is of the form 0x0000...wxyz.
* We expect the autia to indicate failure, producing a pointer of the
* form 0x000e....wxyz. Use xpaci and != for the test, rather than
* extracting explicit bits from the top, because the location of the
* error code "e" depends on the configuration of virtual memory.
*/
if (x != y) {
count++;
}
}
perc = (float) count / (float) TESTS;
printf("Checks Passed: %0.2f%%\n", perc * 100.0);
assert(perc > 0.95);
return 0;
}
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