1 /*
2 american fuzzy lop++ - LD_PRELOAD for fuzzing argv in binaries
3 ------------------------------------------------------------
4
5 Copyright 2019-2024 Kjell Braden <[email protected]>
6
7 Licensed under the Apache License, Version 2.0 (the "License");
8 you may not use this file except in compliance with the License.
9 You may obtain a copy of the License at:
10
11 http://www.apache.org/licenses/LICENSE-2.0
12
13 */
14
15 #define _GNU_SOURCE /* for RTLD_NEXT */
16 #include <dlfcn.h>
17 #include <stdlib.h>
18 #include <stdio.h>
19 #include <unistd.h>
20 #include "argv-fuzz-inl.h"
21
__libc_start_main(int (* main)(int,char **,char **),int argc,char ** argv,void (* init)(void),void (* fini)(void),void (* rtld_fini)(void),void * stack_end)22 int __libc_start_main(int (*main)(int, char **, char **), int argc, char **argv,
23 void (*init)(void), void (*fini)(void),
24 void (*rtld_fini)(void), void *stack_end) {
25
26 int (*orig)(int (*main)(int, char **, char **), int argc, char **argv,
27 void (*init)(void), void (*fini)(void), void (*rtld_fini)(void),
28 void *stack_end);
29 int sub_argc;
30 char **sub_argv;
31
32 (void)argc;
33 (void)argv;
34
35 orig = dlsym(RTLD_NEXT, __func__);
36
37 if (!orig) {
38
39 fprintf(stderr, "hook did not find original %s: %s\n", __func__, dlerror());
40 exit(EXIT_FAILURE);
41
42 }
43
44 sub_argv = afl_init_argv(&sub_argc);
45
46 return orig(main, sub_argc, sub_argv, init, fini, rtld_fini, stack_end);
47
48 }
49
50