-
Notifications
You must be signed in to change notification settings - Fork 40
/
Copy pathafl-fuzz.c
8470 lines (5488 loc) · 225 KB
/
afl-fuzz.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
american fuzzy lop - fuzzer code
--------------------------------
Written and maintained by Michal Zalewski <lcamtuf@google.com>
Forkserver design by Jann Horn <jannhorn@googlemail.com>
Copyright 2013, 2014, 2015 Google Inc. 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
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
#define _GNU_SOURCE
#define _FILE_OFFSET_BITS 64
#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 <netdb.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 <sys/socket.h>
#include <arpa/inet.h>
#include <sys/sendfile.h>
#if defined(__APPLE__) || defined(__FreeBSD__) || defined (__OpenBSD__)
# include <sys/sysctl.h>
#endif /* __APPLE__ || __FreeBSD__ || __OpenBSD__ */
/* 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. */
static 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 */
static u32 exec_tmout = EXEC_TIMEOUT; /* Configurable exec timeout (ms) */
static u64 mem_limit = MEM_LIMIT; /* Memory cap for child (MB) */
static u32 stats_update_freq = 1; /* Stats update frequency (execs) */
static 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_var_check, /* Don't detect variable behavior */
bitmap_changed = 1, /* Time to update bitmap? */
qemu_mode, /* Running in QEMU mode? */
skip_requested, /* Skip request, via SIGUSR1 */
run_over10m; /* Run time over 10 minutes? */
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 */
static u8* trace_bits; /* SHM with instrumentation bitmap */
static u8 virgin_bits[MAP_SIZE], /* Regions yet untouched by fuzzing */
virgin_hang[MAP_SIZE], /* Bits we haven't seen in hangs */
virgin_crash[MAP_SIZE]; /* Bits we haven't seen in crashes */
static s32 shm_id; /* 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? */
static u32 queued_paths, /* Total number of queued testcases */
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 */
current_entry, /* Current queue entry ID */
havoc_div = 1; /* Cycle count divisor for havoc */
static u64 total_crashes, /* Total number of crashes */
unique_crashes, /* Crashes with unique signatures */
total_hangs, /* Total number of hangs */
unique_hangs, /* Hangs with unique signatures */
total_execs, /* Total execve() calls */
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) */
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_hangs; /* Number of hangs 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 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_entries; /* Number of bitmaps counted */
static u32 cpu_core_count; /* CPU core count */
static FILE* plot_file; /* Gnuplot output file */
/* Globals for network support */
static struct addrinfo *N_results = NULL, /* for results from getaddrinfo() */
*N_rp = NULL; /* to iterate through N_results[] */
static struct sockaddr_storage N_myaddr; /* to hold send port info */
static struct sockaddr_storage N_server_addr; /* and server (send side) */
static socklen_t N_myaddrlen = sizeof (struct sockaddr_storage);
/* and length of both */
static u32 N_option_specified = 0; /* 1 if a -N option is present */
static u8* N_option_string = 0; /* points to copy of -N option str */
static u32 N_slen = 0; /* length of the -N option string */
static u32 N_valid = 0; /* 1 if valid URL option to -N */
static u32 N_fuzz_client = 0; /* 1 if target is a network client */
static u32 N_myaddr_valid = 0; /* use established conn or addr */
static s32 N_fd; /* for network file descriptor */
static u32 N_timeout_given = 0; /* use delay before network I/O */
static u32 N_exec_tmout = 0; /* network I/O delay in msec */
static struct timespec N_it; /* structure for nanosleep() call */
struct queue_entry {
u8* fname; /* File name for the test case */
u32 len; /* Input length */
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 */
exec_cksum; /* Checksum of the execution trace */
u64 exec_us, /* Execution time (us) */
handicap, /* Number of queue cycles behind */
depth; /* Path depth */
u8* trace_mini; /* Trace bytes, if kept */
u32 tc_ref; /* Trace bytes ref count */
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 */
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 u8* (*post_handler)(u8* buf, u32* len);
/* 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 };
/* 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_HANG,
/* 02 */ FAULT_CRASH,
/* 03 */ FAULT_ERROR,
/* 04 */ FAULT_NOINST,
/* 05 */ FAULT_NOBITS
};
/* 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 (!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;
}
#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 {
if (unlink(fn)) PFATAL("Unable to remove '%s'", fn);
}
ck_free(fn);
}
/* Append new test case to the queue. */
static void add_to_queue(u8* fname, u32 len, u8 passed_det) {
struct queue_entry* q = ck_alloc(sizeof(struct queue_entry));
q->fname = fname;
q->len = len;
q->depth = cur_depth + 1;
q->passed_det = passed_det;
if (q->depth > max_depth) max_depth = q->depth;
if (queue_top) {
queue_top->next = q;
queue_top = q;
} else q_prev100 = queue = queue_top = q;
queued_paths++;
pending_not_fuzzed++;
if (!(queued_paths % 100)) {
q_prev100->next_100 = q;
q_prev100 = q;
}
last_path_time = get_cur_time();
}
/* Destroy the entire queue. */
static void destroy_queue(void) {
struct queue_entry *q = queue, *n;
while (q) {
n = q->next;
ck_free(q->fname);
ck_free(q->trace_mini);
ck_free(q);
q = n;
}
}
/* Write bitmap to file. The bitmap is useful mostly for the secret
-B option, to focus a separate fuzzing session on a particular
interesting input without rediscovering all the others. */
static void write_bitmap(void) {
u8* fname;
s32 fd;
if (!bitmap_changed) return;
bitmap_changed = 0;
fname = alloc_printf("%s/fuzz_bitmap", out_dir);
fd = open(fname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd < 0) PFATAL("Unable to open '%s'", fname);
ck_write(fd, virgin_bits, MAP_SIZE, fname);
close(fd);
ck_free(fname);
}
/* Read bitmap from file. This is for the -B option again. */
static void read_bitmap(u8* fname) {
s32 fd = open(fname, O_RDONLY);
if (fd < 0) PFATAL("Unable to open '%s'", fname);
ck_read(fd, virgin_bits, MAP_SIZE, fname);
close(fd);
}
/* Check if the current execution path brings anything new to the table.
Update virgin bits to reflect the finds. Returns 1 if the only change is
the hit-count for a particular tuple; 2 if there are new tuples seen.
Updates the map, so subsequent calls will always return 0.
This function is called after every exec() on a fairly large buffer, so
it needs to be fast. We do this in 32-bit and 64-bit flavors. */
#define FFL(_b) (0xffULL << ((_b) << 3))
#define FF(_b) (0xff << ((_b) << 3))
static inline u8 has_new_bits(u8* virgin_map) {
#ifdef __x86_64__
u64* current = (u64*)trace_bits;
u64* virgin = (u64*)virgin_map;
u32 i = (MAP_SIZE >> 3);
#else
u32* current = (u32*)trace_bits;
u32* virgin = (u32*)virgin_map;
u32 i = (MAP_SIZE >> 2);
#endif /* ^__x86_64__ */
u8 ret = 0;
while (i--) {
#ifdef __x86_64__
u64 cur = *current;
u64 vir = *virgin;
#else
u32 cur = *current;
u32 vir = *virgin;
#endif /* ^__x86_64__ */
/* Optimize for *current == ~*virgin, since this will almost always be the
case. */
if (cur & vir) {
if (ret < 2) {
/* This trace did not have any new bytes yet; see if there's any
current[] byte that is non-zero when virgin[] is 0xff. */
#ifdef __x86_64__
if (((cur & FFL(0)) && (vir & FFL(0)) == FFL(0)) ||
((cur & FFL(1)) && (vir & FFL(1)) == FFL(1)) ||
((cur & FFL(2)) && (vir & FFL(2)) == FFL(2)) ||
((cur & FFL(3)) && (vir & FFL(3)) == FFL(3)) ||
((cur & FFL(4)) && (vir & FFL(4)) == FFL(4)) ||
((cur & FFL(5)) && (vir & FFL(5)) == FFL(5)) ||
((cur & FFL(6)) && (vir & FFL(6)) == FFL(6)) ||
((cur & FFL(7)) && (vir & FFL(7)) == FFL(7))) ret = 2;
else ret = 1;
#else
if (((cur & FF(0)) && (vir & FF(0)) == FF(0)) ||
((cur & FF(1)) && (vir & FF(1)) == FF(1)) ||
((cur & FF(2)) && (vir & FF(2)) == FF(2)) ||
((cur & FF(3)) && (vir & FF(3)) == FF(3))) ret = 2;
else ret = 1;
#endif /* ^__x86_64__ */
}
*virgin = vir & ~cur;
}
current++;
virgin++;
}
if (ret && virgin_map == virgin_bits) bitmap_changed = 1;
return ret;
}
/* Count the number of bits set in the provided bitmap. Used for the status
screen several times every second, does not have to be fast. */
static u32 count_bits(u8* mem) {
u32* ptr = (u32*)mem;
u32 i = (MAP_SIZE >> 2);
u32 ret = 0;
while (i--) {
u32 v = *(ptr++);
/* This gets called on the inverse, virgin bitmap; optimize for sparse
data. */
if (v == 0xffffffff) {
ret += 32;
continue;
}
v -= ((v >> 1) & 0x55555555);
v = (v & 0x33333333) + ((v >> 2) & 0x33333333);
ret += (((v + (v >> 4)) & 0xF0F0F0F) * 0x01010101) >> 24;
}
return ret;
}
/* Count the number of bytes set in the bitmap. Called fairly sporadically,
mostly to update the status screen or calibrate and examine confirmed
new paths. */
static u32 count_bytes(u8* mem) {
u32* ptr = (u32*)mem;
u32 i = (MAP_SIZE >> 2);
u32 ret = 0;
while (i--) {
u32 v = *(ptr++);
if (!v) continue;
if (v & FF(0)) ret++;
if (v & FF(1)) ret++;
if (v & FF(2)) ret++;
if (v & FF(3)) ret++;
}
return ret;
}
/* Count the number of non-255 bytes set in the bitmap. Used strictly for the
status screen, several calls per second or so. */
static u32 count_non_255_bytes(u8* mem) {
u32* ptr = (u32*)mem;
u32 i = (MAP_SIZE >> 2);
u32 ret = 0;
while (i--) {
u32 v = *(ptr++);
/* This is called on the virgin bitmap, so optimize for the most likely
case. */
if (v == 0xffffffff) continue;
if ((v & FF(0)) != FF(0)) ret++;
if ((v & FF(1)) != FF(1)) ret++;
if ((v & FF(2)) != FF(2)) ret++;
if ((v & FF(3)) != FF(3)) ret++;
}
return ret;
}
/* Destructively simplify trace by eliminating hit count information
and replacing it with 0x80 or 0x01 depending on whether the tuple
is hit or not. Called on every new crash or hang, should be
reasonably fast. */
#define AREP4(_sym) (_sym), (_sym), (_sym), (_sym)
#define AREP8(_sym) AREP4(_sym), AREP4(_sym)
#define AREP16(_sym) AREP8(_sym), AREP8(_sym)
#define AREP32(_sym) AREP16(_sym), AREP16(_sym)
#define AREP64(_sym) AREP32(_sym), AREP32(_sym)
#define AREP128(_sym) AREP64(_sym), AREP64(_sym)
static u8 simplify_lookup[256] = {
/* 4 */ 1, 128, 128, 128,
/* +4 */ AREP4(128),
/* +8 */ AREP8(128),
/* +16 */ AREP16(128),
/* +32 */ AREP32(128),
/* +64 */ AREP64(128),
/* +128 */ AREP128(128)
};
#ifdef __x86_64__
static void simplify_trace(u64* mem) {
u32 i = MAP_SIZE >> 3;
while (i--) {
/* Optimize for sparse bitmaps. */
if (*mem) {
u8* mem8 = (u8*)mem;
mem8[0] = simplify_lookup[mem8[0]];
mem8[1] = simplify_lookup[mem8[1]];
mem8[2] = simplify_lookup[mem8[2]];
mem8[3] = simplify_lookup[mem8[3]];
mem8[4] = simplify_lookup[mem8[4]];
mem8[5] = simplify_lookup[mem8[5]];
mem8[6] = simplify_lookup[mem8[6]];
mem8[7] = simplify_lookup[mem8[7]];
} else *mem = 0x0101010101010101ULL;
mem++;
}
}
#else
static void simplify_trace(u32* mem) {
u32 i = MAP_SIZE >> 2;
while (i--) {
/* Optimize for sparse bitmaps. */
if (*mem) {
u8* mem8 = (u8*)mem;
mem8[0] = simplify_lookup[mem8[0]];
mem8[1] = simplify_lookup[mem8[1]];
mem8[2] = simplify_lookup[mem8[2]];
mem8[3] = simplify_lookup[mem8[3]];
} else *mem = 0x01010101;
mem++;
}
}
#endif /* ^__x86_64__ */
/* Destructively classify execution counts in a trace. This is used as a
preprocessing step for any newly acquired traces. Called on every exec,
must be fast. */
static u8 count_class_lookup[256] = {
/* 0 - 3: 4 */ 0, 1, 2, 4,
/* 4 - 7: +4 */ AREP4(8),
/* 8 - 15: +8 */ AREP8(16),
/* 16 - 31: +16 */ AREP16(32),
/* 32 - 127: +96 */ AREP64(64), AREP32(64),