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afl-fuzz.c
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afl-fuzz.c
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/*
Copyright 2013 Google LLC All rights reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at:
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
/*
american fuzzy lop - fuzzer code
--------------------------------
Written and maintained by Michal Zalewski <lcamtuf@google.com>
Forkserver design by Jann Horn <jannhorn@googlemail.com>
This is the real deal: the program takes an instrumented binary and
attempts a variety of basic fuzzing tricks, paying close attention to
how they affect the execution path.
*/
#define AFL_MAIN
#define MESSAGES_TO_STDOUT
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#define _FILE_OFFSET_BITS 64
#define DEBUG1 fileonly
#include "config.h"
#include "types.h"
#include "debug.h"
#include "alloc-inl.h"
#include "hash.h"
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <errno.h>
#include <signal.h>
#include <dirent.h>
#include <ctype.h>
#include <fcntl.h>
#include <termios.h>
#include <dlfcn.h>
#include <sched.h>
#include <stdbool.h>
#include <stdarg.h>
#include <limits.h>
#include <sys/wait.h>
#include <sys/time.h>
#include <sys/shm.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/resource.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/file.h>
#include <math.h>
#if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__)
# include <sys/sysctl.h>
#endif /* __APPLE__ || __FreeBSD__ || __OpenBSD__ */
/* For systems that have sched_setaffinity; right now just Linux, but one
can hope... */
#ifdef __linux__
# define HAVE_AFFINITY 1
#endif /* __linux__ */
/* A toggle to export some variables when building as a library. Not very
useful for the general public. */
#ifdef AFL_LIB
# define EXP_ST
#else
# define EXP_ST static
#endif /* ^AFL_LIB */
/* Lots of globals, but mostly for the status UI and other things where it
really makes no sense to haul them around as function parameters. */
EXP_ST u8 *in_dir, /* Input directory with test cases */
*out_file, /* File to fuzz, if any */
*out_dir, /* Working & output directory */
*sync_dir, /* Synchronization directory */
*sync_id, /* Fuzzer ID */
*use_banner, /* Display banner */
*in_bitmap, /* Input bitmap */
*doc_path, /* Path to documentation dir */
*target_path, /* Path to target binary */
*orig_cmdline; /* Original command line */
EXP_ST u32 exec_tmout = EXEC_TIMEOUT; /* Configurable exec timeout (ms) */
static u32 hang_tmout = EXEC_TIMEOUT; /* Timeout used for hang det (ms) */
EXP_ST u64 mem_limit = MEM_LIMIT; /* Memory cap for child (MB) */
static u32 stats_update_freq = 1; /* Stats update frequency (execs) */
static u8 cooling_schedule = 0; /* Cooling schedule for directed fuzzing */
enum {
/* 00 */ SAN_EXP, /* Exponential schedule */
/* 01 */ SAN_LOG, /* Logarithmical schedule */
/* 02 */ SAN_LIN, /* Linear schedule */
/* 03 */ SAN_QUAD /* Quadratic schedule */
};
EXP_ST u8 skip_deterministic, /* Skip deterministic stages? */
force_deterministic, /* Force deterministic stages? */
use_splicing, /* Recombine input files? */
dumb_mode, /* Run in non-instrumented mode? */
score_changed, /* Scoring for favorites changed? */
kill_signal, /* Signal that killed the child */
resuming_fuzz, /* Resuming an older fuzzing job? */
timeout_given, /* Specific timeout given? */
not_on_tty, /* stdout is not a tty */
term_too_small, /* terminal dimensions too small */
uses_asan, /* Target uses ASAN? */
no_forkserver, /* Disable forkserver? */
crash_mode, /* Crash mode! Yeah! */
in_place_resume, /* Attempt in-place resume? */
auto_changed, /* Auto-generated tokens changed? */
no_cpu_meter_red, /* Feng shui on the status screen */
no_arith, /* Skip most arithmetic ops */
shuffle_queue, /* Shuffle input queue? */
bitmap_changed = 1, /* Time to update bitmap? */
bitmap_changed_suf_bb = 1, /* Time to update bitmap? */
qemu_mode, /* Running in QEMU mode? */
skip_requested, /* Skip request, via SIGUSR1 */
run_over10m, /* Run time over 10 minutes? */
persistent_mode, /* Running in persistent mode? */
deferred_mode, /* Deferred forkserver mode? */
fast_cal; /* Try to calibrate faster? */
static s32 out_fd, /* Persistent fd for out_file */
dev_urandom_fd = -1, /* Persistent fd for /dev/urandom */
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) */
static s32 forksrv_pid, /* PID of the fork server */
child_pid = -1, /* PID of the fuzzed program */
out_dir_fd = -1; /* FD of the lock file */
EXP_ST u8* trace_bits; /* SHM with instrumentation bitmap */
EXP_ST u8* trace_bits_c; /* SHM with instrumentation bitmap */
EXP_ST u8* trace_bits_suf; /* SHM with instrumentation bitmap */
EXP_ST u8* trace_bits_suf_bb; /* SHM with instrumentation bitmap */
static u64 hit_bits[MAP_SIZE]; /* @RB@ Hits to every basic block transition */
EXP_ST u8 virgin_bits[MAP_SIZE], /* Regions yet untouched by fuzzing */
target_intersectionBits[MAP_SIZE>>3],
virgin_bits_suf[MAP_SIZE], /* Bits we haven't seen in tmouts */
virgin_bits_suf_target[MAP_SIZE], /* Bits we haven't seen in tmouts */
virgin_bits_suf_bb[MAP_SIZE], /* Bits we haven't seen in tmouts */
virgin_tmout[MAP_SIZE], /* Bits we haven't seen in tmouts */
virgin_crash[MAP_SIZE]; /* Bits we haven't seen in crashes */
static u8 var_bytes[MAP_SIZE]; /* Bytes that appear to be variable */
static s32 shm_id; /* ID of the SHM region */
static s32 shm_id_suf; /* ID of the SHM region */
static s32 shm_id_c; /* ID of the SHM region */
static s32 shm_id_suf_bb; /* ID of the SHM region */
static volatile u8 stop_soon, /* Ctrl-C pressed? */
clear_screen = 1, /* Window resized? */
child_timed_out; /* Traced process timed out? */
EXP_ST u32 queued_paths, /* Total number of queued testcases */
target_paths_total,
queued_variable, /* Testcases with variable behavior */
queued_at_start, /* Total number of initial inputs */
queued_discovered, /* Items discovered during this run */
queued_imported, /* Items imported via -S */
queued_favored, /* Paths deemed favorable */
queued_with_cov, /* Paths with new coverage bytes */
pending_not_fuzzed, /* Queued but not done yet */
pending_favored, /* Pending favored paths */
cur_skipped_paths, /* Abandoned inputs in cur cycle */
cur_depth, /* Current path depth */
max_depth, /* Max path depth */
useless_at_start, /* Number of useless starting paths */
var_byte_count, /* Bitmap bytes with var behavior */
current_entry, /* Current queue entry ID */
temp_current_entry=0,
havoc_div = 1; /* Cycle count divisor for havoc */
EXP_ST u32 queued_paths2, /* Total number of queued testcases */
pending_not_fuzzed2; /* Queued but not done yet */
EXP_ST u64 total_crashes, /* Total number of crashes */
unique_crashes, /* Crashes with unique signatures */
total_tmouts, /* Total number of timeouts */
unique_tmouts, /* Timeouts with unique signatures */
unique_hangs, /* Hangs with unique signatures */
total_execs, /* Total execve() calls */
slowest_exec_ms, /* Slowest testcase non hang in ms */
start_time, /* Unix start time (ms) */
last_path_time, /* Time for most recent path (ms) */
last_crash_time, /* Time for most recent crash (ms) */
last_hang_time, /* Time for most recent hang (ms) */
last_crash_execs, /* Exec counter at last crash */
queue_cycle, /* Queue round counter */
cycles_wo_finds, /* Cycles without any new paths */
trim_execs, /* Execs done to trim input files */
bytes_trim_in, /* Bytes coming into the trimmer */
bytes_trim_out, /* Bytes coming outa the trimmer */
blocks_eff_total, /* Blocks subject to effector maps */
blocks_eff_select; /* Blocks selected as fuzzable */
static u32 subseq_tmouts; /* Number of timeouts in a row */
static u8 *stage_name = "init", /* Name of the current fuzz stage */
*stage_short, /* Short stage name */
*syncing_party; /* Currently syncing with... */
static s32 stage_cur, stage_max; /* Stage progression */
static s32 splicing_with = -1; /* Splicing with which test case? */
static u32 master_id, master_max; /* Master instance job splitting */
static u32 syncing_case; /* Syncing with case #... */
static s32 stage_cur_byte, /* Byte offset of current stage op */
stage_cur_val; /* Value used for stage op */
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 */
static u32 rand_cnt; /* Random number counter */
static u64 total_cal_us, /* Total calibration time (us) */
total_cal_cycles; /* Total calibration cycles */
static u64 total_bitmap_size, /* Total bit count for all bitmaps */
total_bitmap_size_suf, /* Number of bitmaps counted */
total_bitmap_size_suf_target, /* Number of bitmaps counted */
total_bitmap_entries, /* Number of bitmaps counted */
total_bitmap_entries_suf, /* Number of bitmaps counted */
total_bitmap_entries_suf_target; /* Number of bitmaps counted */
static s32 cpu_core_count; /* CPU core count */
#ifdef HAVE_AFFINITY
static s32 cpu_aff = -1; /* Selected CPU core */
#endif /* HAVE_AFFINITY */
static FILE* plot_file; /* Gnuplot output file */
struct queue_entry {
u8* fname; /* File name for the test case */
u32 number; /* File name for the test case */
u32 len; /* Input length */
u64 ttarget_excutes;
u64 crash_excutes;
u64 around_target;
u64 not_useful_seed;
u64 not_pre;
u8 cal_failed, /* Calibration failed? */
trim_done, /* Trimmed? */
was_fuzzed, /* Had any fuzzing done yet? */
passed_det, /* Deterministic stages passed? */
has_new_cov, /* Triggers new coverage? */
var_behavior, /* Variable behavior? */
favored, /* Currently favored? */
fs_redundant; /* Marked as redundant in the fs? */
u32 bitmap_size, /* Number of bits set in bitmap */
fuzz_level,
bitmap_size_suffix,
bitmap_size_suffix_target,
exec_cksum; /* Checksum of the execution trace */
u64 exec_us, /* Execution time (us) */
handicap, /* Number of queue cycles behind */
depth, /* Path depth */
n_fuzz; /* Number of fuzz, does not overflow */
u8* trace_mini; /* Trace bytes, if kept */
u8 *target_branch_trace;
u8 *target_branch_trace_target[TARGETS_NUM];
u8 *target_branch_trace_target_data[TARGETS_NUM];
u32 tc_ref; /* Trace bytes ref count */
double distance; /* Distance to targets */
double distance_target[TARGETS_NUM]; /* Distance to targets */
double suffix_cnt; /* Distance to targets */
u8 is_suf_target;
u8 is_target;
u8 is_rare_target;
u8 is_rare_target_suffix;
u32 rarest_num;
u32 rarest_id;
u8 *trace_bb;
u8 *targets;
u8* fuzzed_branches; /* @RB@ which branches have been done */
u32 *queue_target_branch_hit;
struct queue_entry *next, /* Next element, if any */
*next_100; /* 100 elements ahead */
};
static struct queue_entry *queue, /* Fuzzing queue (linked list) */
*queue_cur, /* Current offset within the queue */
*queue_top, /* Top of the list */
*q_prev100; /* Previous 100 marker */
struct Q2 {
struct queue_entry *queue_this;
struct Q2 *queue_next;
};
static struct Q2 *queue2=NULL,
*queue2_top=NULL,
*queue2_cur=NULL;
static struct queue_entry *queue_temp = NULL;
static struct queue_entry*
top_rated[MAP_SIZE]; /* Top entries for bitmap bytes */
struct extra_data {
u8* data; /* Dictionary token data */
u32 len; /* Dictionary token length */
u32 hit_cnt; /* Use count in the corpus */
};
static struct extra_data* extras; /* Extra tokens to fuzz with */
static u32 extras_cnt; /* Total number of tokens read */
static struct extra_data* a_extras; /* Automatically selected extras */
static u32 a_extras_cnt; /* Total number of tokens available */
static int TTarget_seed = 0;
static int crashSite_seed = 0;
EXP_ST u64 Exit_seed = 0;
static double cur_distance = -1.0; /* Distance of executed input */
static double cur_distance_target[TARGETS_NUM] = {-1.0};
static double max_distance = -1.0; /* Maximal distance for any input */
static double max_distance_target[TARGETS_NUM] = {-1.0};
static double min_distance = -1.0; /* Minimal distance for any input */
static double min_distance_target[TARGETS_NUM] = {-1.0};
static double cur_suffix = -1.0; /* Distance of executed input */
static double max_suffix = -1.0; /* Maximal distance for any input */
static double min_suffix = -1.0; /* Minimal distance for any input */
static u32 t_x = 10; /* Time to exploitation (Default: 10 min) */
static u8* (*post_handler)(u8* buf, u32* len);
static u32 HITCOUNT_THRESHOLD = 10000;
static u32 CO_HITCOUNT_THRESHOLD = 2000;
static u32 MIN_NUMHIT = 1;
/* @RB@ Things about branches */
static u32 vanilla_afl = 1000; /* @RB@ How many executions to conduct
in vanilla AFL mode */
static u32 Inter_TargetSeedNum = 256;
static int rare_branch_exp = 4; /* @RB@ less than 2^rare_branch_exp is rare*/
static int * blacklist;
static int blacklist_size = 1024;
static int blacklist_pos;
static u32 rb_fuzzing = 0; /* @RB@ non-zero branch index + 1 if fuzzing is being done with that branch constant*/
static u32 total_branch_tries = 0;
static u32 successful_branch_tries = 0;
static u8 shadow_mode = 0; /* @RB@ shadow AFL run -- do not modify
queue or branch hits */
static u8 run_with_shadow = 0;
static u8 use_branch_mask = 1;
static int prev_cycle_wo_new = 0;
static int cycle_wo_new = 0;
static int bootstrap = 0; /* @RB@ */
static u8 skip_deterministic_bootstrap = 0;
static int trim_for_branch = 0;
u32* target_count;
u32* target_count_orig;
static u8 is_target;
static u8 is_rare_target;
static FILE* critical_log;
static FILE* distance_log;
static FILE* mutation_log;
static FILE* targets_log;
static FILE* crashes_log;
static u64 last_min_time,
last_target_time = 0;
static u8 explore_status;
static u8 run_in_Q2 = 0;
static u32 target_exec = 0;
static u32 seed_num = 0;
/* Interesting values, as per config.h */
static s8 interesting_8[] = { INTERESTING_8 };
static s16 interesting_16[] = { INTERESTING_8, INTERESTING_16 };
static s32 interesting_32[] = { INTERESTING_8, INTERESTING_16, INTERESTING_32 };
static u32 targets_num = 0;
static u32 targets_num_orig = 0;
static u32 targets_branch_num = 0;
static u32 targets_branch_num_target[TARGETS_NUM] = {0};
static u32 targets_branch_num_target_data[TARGETS_NUM] = {0};
u32 order_edge[MAX_RARE_BRANCHES] = {0};
u32 order_edge_target[TARGETS_NUM][MAX_RARE_BRANCHES] = {0};
u32 order_edge_target_data[TARGETS_NUM][MAX_DATA_SUFFIX] = {0};
int target_ids[TARGETS_NUM] = {1};
u32 edge_curloc[MAP_SIZE] = {0};
u32 edge_distance[MAP_SIZE] = {(u32)(-1)};
struct CE{
u32 edgeidx;
struct CE *next;
};
struct CE *curloc_edge[MAP_SIZE] = {NULL};
static u8* targets_bits;
static u32 *target_suffix; /*now:map<target_id,suffix_num>*/ /*todo::map<target_id,set<suffix_id>>*/
u32 *suffix_bb_execs; /*map<suf_id,execs>*/
u32 *rare_suffix_bb; /*set<suf_id>*/
u32 total_suffix_num;
u32 rare_suffix_num;
u32 distance_val[MAP_SIZE] = {(u32)(-1)};
u32 branch_distance[MAP_SIZE] = {(u32)(-1)};
u32 branch_flag[MAP_SIZE] = {0};
/* Fuzzing stages */
enum {
/* 00 */ STAGE_FLIP1,
/* 01 */ STAGE_FLIP2,
/* 02 */ STAGE_FLIP4,
/* 03 */ STAGE_FLIP8,
/* 04 */ STAGE_FLIP16,
/* 05 */ STAGE_FLIP32,
/* 06 */ STAGE_ARITH8,
/* 07 */ STAGE_ARITH16,
/* 08 */ STAGE_ARITH32,
/* 09 */ STAGE_INTEREST8,
/* 10 */ STAGE_INTEREST16,
/* 11 */ STAGE_INTEREST32,
/* 12 */ STAGE_EXTRAS_UO,
/* 13 */ STAGE_EXTRAS_UI,
/* 14 */ STAGE_EXTRAS_AO,
/* 15 */ STAGE_HAVOC,
/* 16 */ STAGE_SPLICE
};
/* Stage value types */
enum {
/* 00 */ STAGE_VAL_NONE,
/* 01 */ STAGE_VAL_LE,
/* 02 */ STAGE_VAL_BE
};
/* Execution status fault codes */
enum {
/* 00 */ FAULT_NONE,
/* 01 */ FAULT_TMOUT,
/* 02 */ FAULT_CRASH,
/* 03 */ FAULT_ERROR,
/* 04 */ FAULT_NOINST,
/* 05 */ FAULT_NOBITS
};
/* create a new branch mask of the specified size */
static inline u8* alloc_branch_mask(u32 size) {
u8* mem;
if (!size) return NULL;
mem = ck_alloc_nozero(size);
memset(mem, 7, size);
mem[size - 1] = 4;
return mem;
}
void fileonly (char const *fmt, ...) {
static FILE *f = NULL;
char *debugEnv = getenv("DEBUG1");
if (debugEnv != NULL && f == NULL) {
u8 *fn = alloc_printf("%s/target_seed_time.log", out_dir);
f = fopen(fn, "w");
ck_free(fn);
}
if (f != NULL) {
va_list ap;
va_start(ap, fmt);
vfprintf(f, fmt, ap);
va_end(ap);
}
}
/* Get unix time in milliseconds */
static u64 get_cur_time(void) {
struct timeval tv;
struct timezone tz;
gettimeofday(&tv, &tz);
return (tv.tv_sec * 1000ULL) + (tv.tv_usec / 1000);
}
/* Get unix time in microseconds */
static u64 get_cur_time_us(void) {
struct timeval tv;
struct timezone tz;
gettimeofday(&tv, &tz);
return (tv.tv_sec * 1000000ULL) + tv.tv_usec;
}
/* Generate a random number (from 0 to limit - 1). This may
have slight bias. */
static inline u32 UR(u32 limit) {
if (unlikely(!rand_cnt--)) {
u32 seed[2];
ck_read(dev_urandom_fd, &seed, sizeof(seed), "/dev/urandom");
srandom(seed[0]);
rand_cnt = (RESEED_RNG / 2) + (seed[1] % RESEED_RNG);
}
return random() % limit;
}
/* Shuffle an array of pointers. Might be slightly biased. */
static void shuffle_ptrs(void** ptrs, u32 cnt) {
u32 i;
for (i = 0; i < cnt - 2; i++) {
u32 j = i + UR(cnt - i);
void *s = ptrs[i];
ptrs[i] = ptrs[j];
ptrs[j] = s;
}
}
#ifdef HAVE_AFFINITY
/* Build a list of processes bound to specific cores. Returns -1 if nothing
can be found. Assumes an upper bound of 4k CPUs. */
static void bind_to_free_cpu(void) {
DIR* d;
struct dirent* de;
cpu_set_t c;
u8 cpu_used[4096] = { 0 };
u32 i;
if (cpu_core_count < 2) return;
if (getenv("AFL_NO_AFFINITY")) {
WARNF("Not binding to a CPU core (AFL_NO_AFFINITY set).");
return;
}
d = opendir("/proc");
if (!d) {
WARNF("Unable to access /proc - can't scan for free CPU cores.");
return;
}
ACTF("Checking CPU core loadout...");
/* Introduce some jitter, in case multiple AFL tasks are doing the same
thing at the same time... */
usleep(R(1000) * 250);
/* Scan all /proc/<pid>/status entries, checking for Cpus_allowed_list.
Flag all processes bound to a specific CPU using cpu_used[]. This will
fail for some exotic binding setups, but is likely good enough in almost
all real-world use cases. */
while ((de = readdir(d))) {
u8* fn;
FILE* f;
u8 tmp[MAX_LINE];
u8 has_vmsize = 0;
if (!isdigit(de->d_name[0])) continue;
fn = alloc_printf("/proc/%s/status", de->d_name);
if (!(f = fopen(fn, "r"))) {
ck_free(fn);
continue;
}
while (fgets(tmp, MAX_LINE, f)) {
u32 hval;
/* Processes without VmSize are probably kernel tasks. */
if (!strncmp(tmp, "VmSize:\t", 8)) has_vmsize = 1;
if (!strncmp(tmp, "Cpus_allowed_list:\t", 19) &&
!strchr(tmp, '-') && !strchr(tmp, ',') &&
sscanf(tmp + 19, "%u", &hval) == 1 && hval < sizeof(cpu_used) &&
has_vmsize) {
cpu_used[hval] = 1;
break;
}
}
ck_free(fn);
fclose(f);
}
closedir(d);
for (i = 0; i < cpu_core_count; i++) if (!cpu_used[i]) break;
if (i == cpu_core_count) {
SAYF("\n" cLRD "[-] " cRST
"Uh-oh, looks like all %u CPU cores on your system are allocated to\n"
" other instances of afl-fuzz (or similar CPU-locked tasks). Starting\n"
" another fuzzer on this machine is probably a bad plan, but if you are\n"
" absolutely sure, you can set AFL_NO_AFFINITY and try again.\n",
cpu_core_count);
FATAL("No more free CPU cores");
}
OKF("Found a free CPU core, binding to #%u.", i);
cpu_aff = i;
CPU_ZERO(&c);
CPU_SET(i, &c);
if (sched_setaffinity(0, sizeof(c), &c))
PFATAL("sched_setaffinity failed");
}
#endif /* HAVE_AFFINITY */
#ifndef IGNORE_FINDS
/* Helper function to compare buffers; returns first and last differing offset. We
use this to find reasonable locations for splicing two files. */
static void locate_diffs(u8* ptr1, u8* ptr2, u32 len, s32* first, s32* last) {
s32 f_loc = -1;
s32 l_loc = -1;
u32 pos;
for (pos = 0; pos < len; pos++) {
if (*(ptr1++) != *(ptr2++)) {
if (f_loc == -1) f_loc = pos;
l_loc = pos;
}
}
*first = f_loc;
*last = l_loc;
return;
}
#endif /* !IGNORE_FINDS */
/* Describe integer. Uses 12 cyclic static buffers for return values. The value
returned should be five characters or less for all the integers we reasonably
expect to see. */
static u8* DI(u64 val) {
static u8 tmp[12][16];
static u8 cur;
cur = (cur + 1) % 12;
#define CHK_FORMAT(_divisor, _limit_mult, _fmt, _cast) do { \
if (val < (_divisor) * (_limit_mult)) { \
sprintf(tmp[cur], _fmt, ((_cast)val) / (_divisor)); \
return tmp[cur]; \
} \
} while (0)
/* 0-9999 */
CHK_FORMAT(1, 10000, "%llu", u64);
/* 10.0k - 99.9k */
CHK_FORMAT(1000, 99.95, "%0.01fk", double);
/* 100k - 999k */
CHK_FORMAT(1000, 1000, "%lluk", u64);
/* 1.00M - 9.99M */
CHK_FORMAT(1000 * 1000, 9.995, "%0.02fM", double);
/* 10.0M - 99.9M */
CHK_FORMAT(1000 * 1000, 99.95, "%0.01fM", double);
/* 100M - 999M */
CHK_FORMAT(1000 * 1000, 1000, "%lluM", u64);
/* 1.00G - 9.99G */
CHK_FORMAT(1000LL * 1000 * 1000, 9.995, "%0.02fG", double);
/* 10.0G - 99.9G */
CHK_FORMAT(1000LL * 1000 * 1000, 99.95, "%0.01fG", double);
/* 100G - 999G */
CHK_FORMAT(1000LL * 1000 * 1000, 1000, "%lluG", u64);
/* 1.00T - 9.99G */
CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 9.995, "%0.02fT", double);
/* 10.0T - 99.9T */
CHK_FORMAT(1000LL * 1000 * 1000 * 1000, 99.95, "%0.01fT", double);
/* 100T+ */
strcpy(tmp[cur], "infty");
return tmp[cur];
}
/* Describe float. Similar to the above, except with a single
static buffer. */
static u8* DF(double val) {
static u8 tmp[16];
if (val < 99.995) {
sprintf(tmp, "%0.02f", val);
return tmp;
}
if (val < 999.95) {
sprintf(tmp, "%0.01f", val);
return tmp;
}
return DI((u64)val);
}
/* Describe integer as memory size. */
static u8* DMS(u64 val) {
static u8 tmp[12][16];
static u8 cur;
cur = (cur + 1) % 12;
/* 0-9999 */
CHK_FORMAT(1, 10000, "%llu B", u64);
/* 10.0k - 99.9k */
CHK_FORMAT(1024, 99.95, "%0.01f kB", double);
/* 100k - 999k */
CHK_FORMAT(1024, 1000, "%llu kB", u64);
/* 1.00M - 9.99M */
CHK_FORMAT(1024 * 1024, 9.995, "%0.02f MB", double);
/* 10.0M - 99.9M */
CHK_FORMAT(1024 * 1024, 99.95, "%0.01f MB", double);
/* 100M - 999M */
CHK_FORMAT(1024 * 1024, 1000, "%llu MB", u64);
/* 1.00G - 9.99G */
CHK_FORMAT(1024LL * 1024 * 1024, 9.995, "%0.02f GB", double);
/* 10.0G - 99.9G */
CHK_FORMAT(1024LL * 1024 * 1024, 99.95, "%0.01f GB", double);
/* 100G - 999G */
CHK_FORMAT(1024LL * 1024 * 1024, 1000, "%llu GB", u64);
/* 1.00T - 9.99G */
CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 9.995, "%0.02f TB", double);
/* 10.0T - 99.9T */
CHK_FORMAT(1024LL * 1024 * 1024 * 1024, 99.95, "%0.01f TB", double);
#undef CHK_FORMAT
/* 100T+ */
strcpy(tmp[cur], "infty");
return tmp[cur];
}
/* Describe time delta. Returns one static buffer, 34 chars of less. */
static u8* DTD(u64 cur_ms, u64 event_ms) {
static u8 tmp[64];
u64 delta;
s32 t_d, t_h, t_m, t_s;
if (!event_ms) return "none seen yet";
delta = cur_ms - event_ms;
t_d = delta / 1000 / 60 / 60 / 24;
t_h = (delta / 1000 / 60 / 60) % 24;
t_m = (delta / 1000 / 60) % 60;
t_s = (delta / 1000) % 60;
sprintf(tmp, "%s days, %u hrs, %u min, %u sec", DI(t_d), t_h, t_m, t_s);
return tmp;
}
/* Mark deterministic checks as done for a particular queue entry. We use the
.state file to avoid repeating deterministic fuzzing when resuming aborted
scans. */
static void mark_as_det_done(struct queue_entry* q) {
u8* fn = strrchr(q->fname, '/');
s32 fd;
fn = alloc_printf("%s/queue/.state/deterministic_done/%s", out_dir, fn + 1);
fd = open(fn, O_WRONLY | O_CREAT | O_EXCL, 0600);
if (fd < 0) PFATAL("Unable to create '%s'", fn);
close(fd);
ck_free(fn);
q->passed_det = 1;
}
/* Mark as variable. Create symlinks if possible to make it easier to examine
the files. */
static void mark_as_variable(struct queue_entry* q) {
u8 *fn = strrchr(q->fname, '/') + 1, *ldest;
ldest = alloc_printf("../../%s", fn);
fn = alloc_printf("%s/queue/.state/variable_behavior/%s", out_dir, fn);
if (symlink(ldest, fn)) {
s32 fd = open(fn, O_WRONLY | O_CREAT | O_EXCL, 0600);
if (fd < 0) PFATAL("Unable to create '%s'", fn);
close(fd);
}
ck_free(ldest);
ck_free(fn);
q->var_behavior = 1;
}
/* Mark / unmark as redundant (edge-only). This is not used for restoring state,
but may be useful for post-processing datasets. */
static void mark_as_redundant(struct queue_entry* q, u8 state) {
u8* fn;
s32 fd;
if (state == q->fs_redundant) return;
q->fs_redundant = state;
fn = strrchr(q->fname, '/');
fn = alloc_printf("%s/queue/.state/redundant_edges/%s", out_dir, fn + 1);
if (state) {
fd = open(fn, O_WRONLY | O_CREAT | O_EXCL, 0600);
if (fd < 0) PFATAL("Unable to create '%s'", fn);
close(fd);
} else {