34 lines
901 B
C
34 lines
901 B
C
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#include <assert.h>
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static int x;
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int main()
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{
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int *p0 = &x, *p1, *p2, *p3;
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unsigned long salt = 0;
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/*
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* With TBI enabled and a 48-bit VA, there are 7 bits of auth, and so
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* a 1/128 chance of auth = pac(ptr,key,salt) producing zero.
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* Find a salt that creates auth != 0.
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*/
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do {
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salt++;
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asm("pacda %0, %1" : "=r"(p1) : "r"(salt), "0"(p0));
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} while (p0 == p1);
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/*
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* This pac must fail, because the input pointer bears an encryption,
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* and so is not properly extended within bits [55:47]. This will
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* toggle bit 54 in the output...
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*/
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asm("pacda %0, %1" : "=r"(p2) : "r"(salt), "0"(p1));
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/* ... so that the aut must fail, setting bit 53 in the output ... */
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asm("autda %0, %1" : "=r"(p3) : "r"(salt), "0"(p2));
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/* ... which means this equality must not hold. */
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assert(p3 != p0);
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return 0;
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}
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