/*
* fuzzing driver
*
* Copyright Red Hat Inc., 2019
*
* Authors:
* Alexander Bulekov <alxndr@bu.edu>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#ifndef QTEST_FUZZ_H
#define QTEST_FUZZ_H
#include "qemu/units.h"
#include "qapi/error.h"
#include "tests/qtest/libqtest.h"
/**
* A libfuzzer fuzzing target
*
* The QEMU fuzzing binary is built with all available targets, each
* with a unique @name that can be specified on the command-line to
* select which target should run.
*
* A target must implement ->fuzz() to process a random input. If QEMU
* crashes in ->fuzz() then libfuzzer will record a failure.
*
* Fuzzing targets are registered with fuzz_add_target():
*
* static const FuzzTarget fuzz_target = {
* .name = "my-device-fifo",
* .description = "Fuzz the FIFO buffer registers of my-device",
* ...
* };
*
* static void register_fuzz_target(void)
* {
* fuzz_add_target(&fuzz_target);
* }
* fuzz_target_init(register_fuzz_target);
*/
typedef struct FuzzTarget {
const char *name; /* target identifier (passed to --fuzz-target=)*/
const char *description; /* help text */
/*
* Returns the arguments that are passed to qemu/softmmu init(). Freed by
* the caller.
*/
GString *(*get_init_cmdline)(struct FuzzTarget *);
/*
* will run once, prior to running qemu/softmmu init.
* eg: set up shared-memory for communication with the child-process
* Can be NULL
*/
void(*pre_vm_init)(void);
/*
* will run once, after QEMU has been initialized, prior to the fuzz-loop.
* eg: detect the memory map
* Can be NULL
*/
void(*pre_fuzz)(QTestState *);
/*
* accepts and executes an input from libfuzzer. this is repeatedly
* executed during the fuzzing loop. Its should handle setup, input
* execution and cleanup.
* Cannot be NULL
*/
void(*fuzz)(QTestState *, const unsigned char *, size_t);
/*
* The fuzzer can specify a "Custom Crossover" function for combining two
* inputs from the corpus. This function is sometimes called by libfuzzer
* when mutating inputs.
*
* data1: location of first input
* size1: length of first input
* data1: location of second input
* size1: length of second input
* out: where to place the resulting, mutated input
* max_out_size: the maximum length of the input that can be placed in out
* seed: the seed that should be used to make mutations deterministic, when
* needed
*
* See libfuzzer's LLVMFuzzerCustomCrossOver API for more info.
*
* Can be NULL
*/
size_t(*crossover)(const uint8_t *data1, size_t size1,
const uint8_t *data2, size_t size2,
uint8_t *out, size_t max_out_size,
unsigned int seed);
void *opaque;
} FuzzTarget;
void flush_events(QTestState *);
void reboot(QTestState *);
/* Use the QTest ASCII protocol or call address_space API directly?*/
void fuzz_qtest_set_serialize(bool option);
/*
* makes a copy of *target and adds it to the target-list.
* i.e. fine to set up target on the caller's stack
*/
void fuzz_add_target(const FuzzTarget *target);
size_t LLVMFuzzerCustomCrossOver(const uint8_t *data1, size_t size1,
const uint8_t *data2, size_t size2,
uint8_t *out, size_t max_out_size,
unsigned int seed);
int LLVMFuzzerTestOneInput(const unsigned char *Data, size_t Size);
int LLVMFuzzerInitialize(int *argc, char ***argv, char ***envp);
#endif
