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android / platform / external / AFLplusplus / 7470b475 / . / src / afl-fuzz-redqueen.c
blob: 1ae6ab544c1634bf27e2efd0bee9e3d3258f6897 [file] [log] [blame]
/*
american fuzzy lop++ - redqueen implementation on top of cmplog
---------------------------------------------------------------
Originally written by Michal Zalewski
Forkserver design by Jann Horn <jannhorn@googlemail.com>
Now maintained by by Marc Heuse <mh@mh-sec.de>,
Heiko Eißfeldt <heiko.eissfeldt@hexco.de> and
Andrea Fioraldi <andreafioraldi@gmail.com>
Copyright 2016, 2017 Google Inc. All rights reserved.
Copyright 2019-2020 AFLplusplus Project. 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
Shared code to handle the shared memory. This is used by the fuzzer
as well the other components like afl-tmin, afl-showmap, etc...
*/
#include <limits.h>
#include "afl-fuzz.h"
#include "cmplog.h"
///// Colorization
struct range {
u32 start;
u32 end;
struct range *next;
};
static struct range *add_range(struct range *ranges, u32 start, u32 end) {
struct range *r = ck_alloc_nozero(sizeof(struct range));
r->start = start;
r->end = end;
r->next = ranges;
return r;
}
static struct range *pop_biggest_range(struct range **ranges) {
struct range *r = *ranges;
struct range *prev = NULL;
struct range *rmax = NULL;
struct range *prev_rmax = NULL;
u32 max_size = 0;
while (r) {
u32 s = r->end - r->start;
if (s >= max_size) {
max_size = s;
prev_rmax = prev;
rmax = r;
}
prev = r;
r = r->next;
}
if (rmax) {
if (prev_rmax) {
prev_rmax->next = rmax->next;
} else {
*ranges = rmax->next;
}
}
return rmax;
}
static u8 get_exec_checksum(afl_state_t *afl, u8 *buf, u32 len, u64 *cksum) {
if (unlikely(common_fuzz_stuff(afl, buf, len))) { return 1; }
*cksum = hash64(afl->fsrv.trace_bits, afl->fsrv.map_size, HASH_CONST);
return 0;
}
static void rand_replace(afl_state_t *afl, u8 *buf, u32 len) {
u32 i;
for (i = 0; i < len; ++i) {
buf[i] = rand_below(afl, 256);
}
}
static u8 colorization(afl_state_t *afl, u8 *buf, u32 len, u64 exec_cksum) {
struct range *ranges = add_range(NULL, 0, len);
u8 * backup = ck_alloc_nozero(len);
u8 needs_write = 0;
u64 orig_hit_cnt, new_hit_cnt;
orig_hit_cnt = afl->queued_paths + afl->unique_crashes;
afl->stage_name = "colorization";
afl->stage_short = "colorization";
afl->stage_max = 1000;
struct range *rng = NULL;
afl->stage_cur = 0;
while ((rng = pop_biggest_range(&ranges)) != NULL &&
afl->stage_cur < afl->stage_max) {
u32 s = rng->end - rng->start;
if (s != 0) {
/* Range not empty */
memcpy(backup, buf + rng->start, s);
rand_replace(afl, buf + rng->start, s);
u64 cksum;
u64 start_us = get_cur_time_us();
if (unlikely(get_exec_checksum(afl, buf, len, &cksum))) {
goto checksum_fail;
}
u64 stop_us = get_cur_time_us();
/* Discard if the mutations change the paths or if it is too decremental
in speed */
if (cksum != exec_cksum ||
((stop_us - start_us > 2 * afl->queue_cur->exec_us) &&
likely(!afl->fixed_seed))) {
ranges = add_range(ranges, rng->start, rng->start + s / 2);
ranges = add_range(ranges, rng->start + s / 2 + 1, rng->end);
memcpy(buf + rng->start, backup, s);
} else {
needs_write = 1;
}
}
ck_free(rng);
rng = NULL;
++afl->stage_cur;
}
if (afl->stage_cur < afl->stage_max) { afl->queue_cur->fully_colorized = 1; }
new_hit_cnt = afl->queued_paths + afl->unique_crashes;
afl->stage_finds[STAGE_COLORIZATION] += new_hit_cnt - orig_hit_cnt;
afl->stage_cycles[STAGE_COLORIZATION] += afl->stage_cur;
ck_free(backup);
ck_free(rng);
rng = NULL;
while (ranges) {
rng = ranges;
ranges = rng->next;
ck_free(rng);
rng = NULL;
}
// save the input with the high entropy
if (needs_write) {
s32 fd;
if (afl->no_unlink) {
fd = open(afl->queue_cur->fname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
} else {
unlink(afl->queue_cur->fname); /* ignore errors */
fd = open(afl->queue_cur->fname, O_WRONLY | O_CREAT | O_EXCL, 0600);
}
if (fd < 0) { PFATAL("Unable to create '%s'", afl->queue_cur->fname); }
ck_write(fd, buf, len, afl->queue_cur->fname);
afl->queue_cur->len = len; // no-op, just to be 100% safe
close(fd);
}
return 0;
checksum_fail:
if (rng) { ck_free(rng); }
ck_free(backup);
while (ranges) {
rng = ranges;
ranges = rng->next;
ck_free(rng);
rng = NULL;
}
// TODO: clang notices a _potential_ leak of mem pointed to by rng
return 1;
}
///// Input to State replacement
static u8 its_fuzz(afl_state_t *afl, u8 *buf, u32 len, u8 *status) {
u64 orig_hit_cnt, new_hit_cnt;
orig_hit_cnt = afl->queued_paths + afl->unique_crashes;
if (unlikely(common_fuzz_stuff(afl, buf, len))) { return 1; }
new_hit_cnt = afl->queued_paths + afl->unique_crashes;
if (unlikely(new_hit_cnt != orig_hit_cnt)) {
*status = 1;
} else {
*status = 2;
}
return 0;
}
static long long strntoll(const char *str, size_t sz, char **end, int base) {
char buf[64];
long long ret;
const char *beg = str;
for (; beg && sz && *beg == ' '; beg++, sz--) {};
if (!sz || sz >= sizeof(buf)) {
if (end) *end = (char *)str;
return 0;
}
memcpy(buf, beg, sz);
buf[sz] = '\0';
ret = strtoll(buf, end, base);
if (ret == LLONG_MIN || ret == LLONG_MAX) return ret;
if (end) *end = (char *)beg + (*end - buf);
return ret;
}
static unsigned long long strntoull(const char *str, size_t sz, char **end,
int base) {
char buf[64];
unsigned long long ret;
const char * beg = str;
for (; beg && sz && *beg == ' '; beg++, sz--)
;
if (!sz || sz >= sizeof(buf)) {
if (end) *end = (char *)str;
return 0;
}
memcpy(buf, beg, sz);
buf[sz] = '\0';
ret = strtoull(buf, end, base);
if (end) *end = (char *)beg + (*end - buf);
return ret;
}
static u8 cmp_extend_encoding(afl_state_t *afl, struct cmp_header *h,
u64 pattern, u64 repl, u64 o_pattern, u32 idx,
u8 *orig_buf, u8 *buf, u32 len, u8 do_reverse,
u8 *status) {
if (!buf) { FATAL("BUG: buf was NULL. Please report this.\n"); }
u64 *buf_64 = (u64 *)&buf[idx];
u32 *buf_32 = (u32 *)&buf[idx];
u16 *buf_16 = (u16 *)&buf[idx];
u8 * buf_8 = &buf[idx];
u64 *o_buf_64 = (u64 *)&orig_buf[idx];
u32 *o_buf_32 = (u32 *)&orig_buf[idx];
u16 *o_buf_16 = (u16 *)&orig_buf[idx];
u8 * o_buf_8 = &orig_buf[idx];
u32 its_len = len - idx;
// *status = 0;
u8 * endptr;
u8 use_num = 0, use_unum = 0;
unsigned long long unum;
long long num;
if (afl->queue_cur->is_ascii) {
endptr = buf_8;
num = strntoll(buf_8, len - idx, (char **)&endptr, 0);
if (endptr == buf_8) {
unum = strntoull(buf_8, len - idx, (char **)&endptr, 0);
if (endptr == buf_8) use_unum = 1;
} else
use_num = 1;
}
if (use_num && (u64)num == pattern) {
size_t old_len = endptr - buf_8;
size_t num_len = snprintf(NULL, 0, "%lld", num);
u8 *new_buf = afl_realloc((void **)&afl->out_scratch_buf, len + num_len);
if (unlikely(!new_buf)) { PFATAL("alloc"); }
memcpy(new_buf, buf, idx);
snprintf(new_buf + idx, num_len, "%lld", num);
memcpy(new_buf + idx + num_len, buf_8 + old_len, len - idx - old_len);
if (unlikely(its_fuzz(afl, new_buf, len, status))) { return 1; }
} else if (use_unum && unum == pattern) {
size_t old_len = endptr - buf_8;
size_t num_len = snprintf(NULL, 0, "%llu", unum);
u8 *new_buf = afl_realloc((void **)&afl->out_scratch_buf, len + num_len);
if (unlikely(!new_buf)) { PFATAL("alloc"); }
memcpy(new_buf, buf, idx);
snprintf(new_buf + idx, num_len, "%llu", unum);
memcpy(new_buf + idx + num_len, buf_8 + old_len, len - idx - old_len);
if (unlikely(its_fuzz(afl, new_buf, len, status))) { return 1; }
}
if (SHAPE_BYTES(h->shape) >= 8 && *status != 1) {
if (its_len >= 8 && *buf_64 == pattern && *o_buf_64 == o_pattern) {
*buf_64 = repl;
if (unlikely(its_fuzz(afl, buf, len, status))) { return 1; }
*buf_64 = pattern;
}
// reverse encoding
if (do_reverse && *status != 1) {
if (unlikely(cmp_extend_encoding(afl, h, SWAP64(pattern), SWAP64(repl),
SWAP64(o_pattern), idx, orig_buf, buf,
len, 0, status))) {
return 1;
}
}
}
if (SHAPE_BYTES(h->shape) >= 4 && *status != 1) {
if (its_len >= 4 && *buf_32 == (u32)pattern &&
*o_buf_32 == (u32)o_pattern) {
*buf_32 = (u32)repl;
if (unlikely(its_fuzz(afl, buf, len, status))) { return 1; }
*buf_32 = pattern;
}
// reverse encoding
if (do_reverse && *status != 1) {
if (unlikely(cmp_extend_encoding(afl, h, SWAP32(pattern), SWAP32(repl),
SWAP32(o_pattern), idx, orig_buf, buf,
len, 0, status))) {
return 1;
}
}
}
if (SHAPE_BYTES(h->shape) >= 2 && *status != 1) {
if (its_len >= 2 && *buf_16 == (u16)pattern &&
*o_buf_16 == (u16)o_pattern) {
*buf_16 = (u16)repl;
if (unlikely(its_fuzz(afl, buf, len, status))) { return 1; }
*buf_16 = (u16)pattern;
}
// reverse encoding
if (do_reverse && *status != 1) {
if (unlikely(cmp_extend_encoding(afl, h, SWAP16(pattern), SWAP16(repl),
SWAP16(o_pattern), idx, orig_buf, buf,
len, 0, status))) {
return 1;
}
}
}
if (SHAPE_BYTES(h->shape) >= 1 && *status != 1) {
if (its_len >= 1 && *buf_8 == (u8)pattern && *o_buf_8 == (u8)o_pattern) {
*buf_8 = (u8)repl;
if (unlikely(its_fuzz(afl, buf, len, status))) { return 1; }
*buf_8 = (u8)pattern;
}
}
return 0;
}
static void try_to_add_to_dict(afl_state_t *afl, u64 v, u8 shape) {
u8 *b = (u8 *)&v;
u32 k;
u8 cons_ff = 0, cons_0 = 0;
for (k = 0; k < shape; ++k) {
if (b[k] == 0) {
++cons_0;
} else if (b[k] == 0xff) {
++cons_0;
} else {
cons_0 = cons_ff = 0;
}
if (cons_0 > 1 || cons_ff > 1) { return; }
}
maybe_add_auto(afl, (u8 *)&v, shape);
u64 rev;
switch (shape) {
case 1:
break;
case 2:
rev = SWAP16((u16)v);
maybe_add_auto(afl, (u8 *)&rev, shape);
break;
case 4:
rev = SWAP32((u32)v);
maybe_add_auto(afl, (u8 *)&rev, shape);
break;
case 8:
rev = SWAP64(v);
maybe_add_auto(afl, (u8 *)&rev, shape);
break;
}
}
static u8 cmp_fuzz(afl_state_t *afl, u32 key, u8 *orig_buf, u8 *buf, u32 len) {
struct cmp_header *h = &afl->shm.cmp_map->headers[key];
u32 i, j, idx;
u32 loggeds = h->hits;
if (h->hits > CMP_MAP_H) { loggeds = CMP_MAP_H; }
u8 status = 0;
// opt not in the paper
u32 fails;
u8 found_one = 0;
/* loop cmps are useless, detect and ignore them */
u64 s_v0, s_v1;
u8 s_v0_fixed = 1, s_v1_fixed = 1;
u8 s_v0_inc = 1, s_v1_inc = 1;
u8 s_v0_dec = 1, s_v1_dec = 1;
for (i = 0; i < loggeds; ++i) {
fails = 0;
struct cmp_operands *o = &afl->shm.cmp_map->log[key][i];
// loop detection code
if (i == 0) {
s_v0 = o->v0;
s_v1 = o->v1;
} else {
if (s_v0 != o->v0) { s_v0_fixed = 0; }
if (s_v1 != o->v1) { s_v1_fixed = 0; }
if (s_v0 + 1 != o->v0) { s_v0_inc = 0; }
if (s_v1 + 1 != o->v1) { s_v1_inc = 0; }
if (s_v0 - 1 != o->v0) { s_v0_dec = 0; }
if (s_v1 - 1 != o->v1) { s_v1_dec = 0; }
s_v0 = o->v0;
s_v1 = o->v1;
}
struct cmp_operands *orig_o = &afl->orig_cmp_map->log[key][i];
// opt not in the paper
for (j = 0; j < i; ++j) {
if (afl->shm.cmp_map->log[key][j].v0 == o->v0 &&
afl->shm.cmp_map->log[key][i].v1 == o->v1) {
goto cmp_fuzz_next_iter;
}
}
for (idx = 0; idx < len && fails < 8; ++idx) {
status = 0;
if (unlikely(cmp_extend_encoding(afl, h, o->v0, o->v1, orig_o->v0, idx,
orig_buf, buf, len, 1, &status))) {
return 1;
}
if (status == 2) {
++fails;
} else if (status == 1) {
break;
}
status = 0;
if (unlikely(cmp_extend_encoding(afl, h, o->v1, o->v0, orig_o->v1, idx,
orig_buf, buf, len, 1, &status))) {
return 1;
}
if (status == 2) {
++fails;
} else if (status == 1) {
break;
}
}
if (status == 1) { found_one = 1; }
// If failed, add to dictionary
if (fails == 8) {
if (afl->pass_stats[key].total == 0) {
try_to_add_to_dict(afl, o->v0, SHAPE_BYTES(h->shape));
try_to_add_to_dict(afl, o->v1, SHAPE_BYTES(h->shape));
}
}
cmp_fuzz_next_iter:
afl->stage_cur++;
}
if (loggeds > 3 && ((s_v0_fixed && s_v1_inc) || (s_v1_fixed && s_v0_inc) ||
(s_v0_fixed && s_v1_dec) || (s_v1_fixed && s_v0_dec))) {
afl->pass_stats[key].total = afl->pass_stats[key].faileds = 0xff;
}
if (!found_one && afl->pass_stats[key].faileds < 0xff) {
afl->pass_stats[key].faileds++;
}
if (afl->pass_stats[key].total < 0xff) { afl->pass_stats[key].total++; }
return 0;
}
static u8 rtn_extend_encoding(afl_state_t *afl, u8 *pattern, u8 *repl,
u8 *o_pattern, u32 idx, u8 *orig_buf, u8 *buf,
u32 len, u8 *status) {
u32 i;
u32 its_len = MIN((u32)32, len - idx);
u8 save[32];
memcpy(save, &buf[idx], its_len);
*status = 0;
for (i = 0; i < its_len; ++i) {
if (pattern[i] != buf[idx + i] || o_pattern[i] != orig_buf[idx + i] ||
*status == 1) {
break;
}
buf[idx + i] = repl[i];
if (unlikely(its_fuzz(afl, buf, len, status))) { return 1; }
}
memcpy(&buf[idx], save, i);
return 0;
}
static u8 rtn_fuzz(afl_state_t *afl, u32 key, u8 *orig_buf, u8 *buf, u32 len) {
struct cmp_header *h = &afl->shm.cmp_map->headers[key];
u32 i, j, idx;
u32 loggeds = h->hits;
if (h->hits > CMP_MAP_RTN_H) { loggeds = CMP_MAP_RTN_H; }
u8 status = 0;
// opt not in the paper
u32 fails = 0;
u8 found_one = 0;
for (i = 0; i < loggeds; ++i) {
fails = 0;
struct cmpfn_operands *o =
&((struct cmpfn_operands *)afl->shm.cmp_map->log[key])[i];
struct cmpfn_operands *orig_o =
&((struct cmpfn_operands *)afl->orig_cmp_map->log[key])[i];
// opt not in the paper
for (j = 0; j < i; ++j) {
if (!memcmp(&((struct cmpfn_operands *)afl->shm.cmp_map->log[key])[j], o,
sizeof(struct cmpfn_operands))) {
goto rtn_fuzz_next_iter;
}
}
for (idx = 0; idx < len && fails < 8; ++idx) {
if (unlikely(rtn_extend_encoding(afl, o->v0, o->v1, orig_o->v0, idx,
orig_buf, buf, len, &status))) {
return 1;
}
if (status == 2) {
++fails;
} else if (status == 1) {
break;
}
if (unlikely(rtn_extend_encoding(afl, o->v1, o->v0, orig_o->v1, idx,
orig_buf, buf, len, &status))) {
return 1;
}
if (status == 2) {
++fails;
} else if (status == 1) {
break;
}
}
if (status == 1) { found_one = 1; }
// If failed, add to dictionary
if (fails == 8) {
if (afl->pass_stats[key].total == 0) {
maybe_add_auto(afl, o->v0, SHAPE_BYTES(h->shape));
maybe_add_auto(afl, o->v1, SHAPE_BYTES(h->shape));
}
}
rtn_fuzz_next_iter:
afl->stage_cur++;
}
if (!found_one && afl->pass_stats[key].faileds < 0xff) {
afl->pass_stats[key].faileds++;
}
if (afl->pass_stats[key].total < 0xff) { afl->pass_stats[key].total++; }
return 0;
}
///// Input to State stage
// afl->queue_cur->exec_cksum
u8 input_to_state_stage(afl_state_t *afl, u8 *orig_buf, u8 *buf, u32 len,
u64 exec_cksum) {
u8 r = 1;
if (afl->orig_cmp_map == NULL) {
afl->orig_cmp_map = ck_alloc_nozero(sizeof(struct cmp_map));
}
if (afl->pass_stats == NULL) {
afl->pass_stats = ck_alloc(sizeof(struct afl_pass_stat) * CMP_MAP_W);
}
// do it manually, forkserver clear only afl->fsrv.trace_bits
memset(afl->shm.cmp_map->headers, 0, sizeof(afl->shm.cmp_map->headers));
if (unlikely(common_fuzz_cmplog_stuff(afl, buf, len))) { return 1; }
memcpy(afl->orig_cmp_map, afl->shm.cmp_map, sizeof(struct cmp_map));
if (unlikely(colorization(afl, buf, len, exec_cksum))) { return 1; }
// do it manually, forkserver clear only afl->fsrv.trace_bits
memset(afl->shm.cmp_map->headers, 0, sizeof(afl->shm.cmp_map->headers));
if (unlikely(common_fuzz_cmplog_stuff(afl, buf, len))) { return 1; }
u64 orig_hit_cnt, new_hit_cnt;
u64 orig_execs = afl->fsrv.total_execs;
orig_hit_cnt = afl->queued_paths + afl->unique_crashes;
afl->stage_name = "input-to-state";
afl->stage_short = "its";
afl->stage_max = 0;
afl->stage_cur = 0;
u32 k;
for (k = 0; k < CMP_MAP_W; ++k) {
if (!afl->shm.cmp_map->headers[k].hits) { continue; }
if (afl->pass_stats[k].total &&
(rand_below(afl, afl->pass_stats[k].total) >=
afl->pass_stats[k].faileds ||
afl->pass_stats[k].total == 0xff)) {
afl->shm.cmp_map->headers[k].hits = 0; // ignore this cmp
}
if (afl->shm.cmp_map->headers[k].type == CMP_TYPE_INS) {
afl->stage_max +=
MIN((u32)(afl->shm.cmp_map->headers[k].hits), (u32)CMP_MAP_H);
} else {
afl->stage_max +=
MIN((u32)(afl->shm.cmp_map->headers[k].hits), (u32)CMP_MAP_RTN_H);
}
}
for (k = 0; k < CMP_MAP_W; ++k) {
if (!afl->shm.cmp_map->headers[k].hits) { continue; }
if (afl->shm.cmp_map->headers[k].type == CMP_TYPE_INS) {
if (unlikely(cmp_fuzz(afl, k, orig_buf, buf, len))) { goto exit_its; }
} else {
if (unlikely(rtn_fuzz(afl, k, orig_buf, buf, len))) { goto exit_its; }
}
}
r = 0;
exit_its:
new_hit_cnt = afl->queued_paths + afl->unique_crashes;
afl->stage_finds[STAGE_ITS] += new_hit_cnt - orig_hit_cnt;
afl->stage_cycles[STAGE_ITS] += afl->fsrv.total_execs - orig_execs;
memcpy(orig_buf, buf, len);
return r;
}