fuzz.h

/* Feeding generated bytes to the code that parses what comes off the wire.
 *
 * Each harness is an LLVMFuzzerTestOneInput, so a real fuzzer drives it.
 * Where there is no fuzzer -- Apple's clang ships no libFuzzer runtime --
 * standalone.c supplies a main that replays the committed corpus and then a
 * deterministic stream of its own, which says the harness is wired up
 * correctly and nothing about coverage.
 *
 * What is being looked for is memory safety, not wrong answers: these inputs
 * are meant to be rejected, and the question is how they are rejected.
 */
#ifndef CRYPTON_TESTS_FUZZ_H
#define CRYPTON_TESTS_FUZZ_H

#include <stdint.h>
#include <stddef.h>
#include <string.h>

int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size);

/* Carve a fixed-width field out of the input.  Short input means the harness
 * returns rather than reading past the end, which is the harness's own bug to
 * avoid and not the library's to report. */
static int fz_take(const uint8_t **p, size_t *left, void *out, size_t n)
{
	if (*left < n)
		return 0;
	memcpy(out, *p, n);
	*p += n;
	*left -= n;
	return 1;
}

#endif