diff options
| author | David Carlier <devnexen@gmail.com> | 2019-07-30 07:25:56 +0000 |
|---|---|---|
| committer | Tobias Kortkamp <t@tobik.me> | 2019-08-08 08:29:25 +0200 |
| commit | 8b6a4e575978fac83155efd90d39030c84b2a755 (patch) | |
| tree | b99583d65dba76a15cd59e8eea15b770692129b3 | |
| parent | 07df1e303419a642b96750411af99b586d0ea5a0 (diff) | |
| download | afl++-8b6a4e575978fac83155efd90d39030c84b2a755.tar.gz | |
For BSD/APPLE platform use native random calls
Solution not involving file descriptors, seeded upon fork and on
a regular basis.
Signed-off-by: Tobias Kortkamp <t@tobik.me>
| -rw-r--r-- | afl-fuzz.c | 28 |
1 files changed, 21 insertions, 7 deletions
@@ -62,6 +62,7 @@ #if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__) # include <sys/sysctl.h> +# define HAVE_ARC4RANDOM 1 #endif /* __APPLE__ || __FreeBSD__ || __OpenBSD__ */ /* For systems that have sched_setaffinity; right now just Linux, but one @@ -219,7 +220,9 @@ EXP_ST u8 skip_deterministic, /* Skip deterministic stages? */ fast_cal; /* Try to calibrate faster? */ static s32 out_fd, /* Persistent fd for out_file */ +#ifndef HAVE_ARC4RANDOM dev_urandom_fd = -1, /* Persistent fd for /dev/urandom */ +#endif dev_null_fd = -1, /* Persistent fd for /dev/null */ fsrv_ctl_fd, /* Fork server control pipe (write) */ fsrv_st_fd; /* Fork server status pipe (read) */ @@ -297,7 +300,9 @@ static u8 stage_val_type; /* Value type (STAGE_VAL_*) */ static u64 stage_finds[32], /* Patterns found per fuzz stage */ stage_cycles[32]; /* Execs per fuzz stage */ +#ifndef HAVE_ARC4RANDOM static u32 rand_cnt; /* Random number counter */ +#endif static u64 total_cal_us, /* Total calibration time (us) */ total_cal_cycles; /* Total calibration cycles */ @@ -641,14 +646,8 @@ static void trim_py(char** ret, size_t* retlen) { int select_algorithm(void) { int i_puppet, j_puppet; - u32 seed[2]; - - if (!fixed_seed) { - ck_read(dev_urandom_fd, &seed, sizeof(seed), "/dev/urandom"); - srandom(seed[0]); - } - double sele = ((double)(random()%10000)*0.0001); + double sele = ((double)(UR(10000))*0.0001); j_puppet = 0; for (i_puppet = 0; i_puppet < operator_num; i_puppet++) { if (unlikely(i_puppet == 0)) { @@ -699,7 +698,15 @@ static u64 get_cur_time_us(void) { have slight bias. */ static inline u32 UR(u32 limit) { +#ifdef HAVE_ARC4RANDOM + if (fixed_seed) { + return random() % limit; + } + /* The boundary not being necessarily a power of 2, + we need to ensure the result uniformity. */ + return arc4random_uniform(limit); +#else if (!fixed_seed && unlikely(!rand_cnt--)) { u32 seed[2]; @@ -709,6 +716,7 @@ static inline u32 UR(u32 limit) { } return random() % limit; +#endif } @@ -2407,7 +2415,9 @@ EXP_ST void init_forkserver(char** argv) { close(out_dir_fd); close(dev_null_fd); +#ifndef HAVE_ARC4RANDOM close(dev_urandom_fd); +#endif close(fileno(plot_file)); /* This should improve performance a bit, since it stops the linker from @@ -2681,7 +2691,9 @@ static u8 run_target(char** argv, u32 timeout) { close(dev_null_fd); close(out_dir_fd); +#ifndef HAVE_ARC4RANDOM close(dev_urandom_fd); +#endif close(fileno(plot_file)); /* Set sane defaults for ASAN if nothing else specified. */ @@ -11466,8 +11478,10 @@ EXP_ST void setup_dirs_fds(void) { dev_null_fd = open("/dev/null", O_RDWR); if (dev_null_fd < 0) PFATAL("Unable to open /dev/null"); +#ifndef HAVE_ARC4RANDOM dev_urandom_fd = open("/dev/urandom", O_RDONLY); if (dev_urandom_fd < 0) PFATAL("Unable to open /dev/urandom"); +#endif /* Gnuplot output file. */ |