1 // -*- C++ -*-
2 //===------------------------- fuzzing.cpp -------------------------------===//
3 //
4 // The LLVM Compiler Infrastructure
5 //
6 // This file is dual licensed under the MIT and the University of Illinois Open
7 // Source Licenses. See LICENSE.TXT for details.
8 //
9 //===----------------------------------------------------------------------===//
10
11 // A set of routines to use when fuzzing the algorithms in libc++
12 // Each one tests a single algorithm.
13 //
14 // They all have the form of:
15 // int `algorithm`(const uint8_t *data, size_t size);
16 //
17 // They perform the operation, and then check to see if the results are correct.
18 // If so, they return zero, and non-zero otherwise.
19 //
20 // For example, sort calls std::sort, then checks two things:
21 // (1) The resulting vector is sorted
22 // (2) The resulting vector contains the same elements as the original data.
23
24
25
26 #include "fuzzing.h"
27 #include <vector>
28 #include <algorithm>
29 #include <functional>
30 #include <regex>
31 #include <cassert>
32
33 #include <iostream>
34
35 // If we had C++14, we could use the four iterator version of is_permutation and equal
36
37 namespace fuzzing {
38
39 // This is a struct we can use to test the stable_XXX algorithms.
40 // perform the operation on the key, then check the order of the payload.
41
42 struct stable_test {
43 uint8_t key;
44 size_t payload;
45
stable_testfuzzing::stable_test46 stable_test(uint8_t k) : key(k), payload(0) {}
stable_testfuzzing::stable_test47 stable_test(uint8_t k, size_t p) : key(k), payload(p) {}
48 };
49
swap(stable_test & lhs,stable_test & rhs)50 void swap(stable_test &lhs, stable_test &rhs)
51 {
52 using std::swap;
53 swap(lhs.key, rhs.key);
54 swap(lhs.payload, rhs.payload);
55 }
56
57 struct key_less
58 {
operator ()fuzzing::key_less59 bool operator () (const stable_test &lhs, const stable_test &rhs) const
60 {
61 return lhs.key < rhs.key;
62 }
63 };
64
65 struct payload_less
66 {
operator ()fuzzing::payload_less67 bool operator () (const stable_test &lhs, const stable_test &rhs) const
68 {
69 return lhs.payload < rhs.payload;
70 }
71 };
72
73 struct total_less
74 {
operator ()fuzzing::total_less75 bool operator () (const stable_test &lhs, const stable_test &rhs) const
76 {
77 return lhs.key == rhs.key ? lhs.payload < rhs.payload : lhs.key < rhs.key;
78 }
79 };
80
operator ==(const stable_test & lhs,const stable_test & rhs)81 bool operator==(const stable_test &lhs, const stable_test &rhs)
82 {
83 return lhs.key == rhs.key && lhs.payload == rhs.payload;
84 }
85
86
87 template<typename T>
88 struct is_even
89 {
operator ()fuzzing::is_even90 bool operator () (const T &t) const
91 {
92 return t % 2 == 0;
93 }
94 };
95
96
97 template<>
98 struct is_even<stable_test>
99 {
operator ()fuzzing::is_even100 bool operator () (const stable_test &t) const
101 {
102 return t.key % 2 == 0;
103 }
104 };
105
106 typedef std::vector<uint8_t> Vec;
107 typedef std::vector<stable_test> StableVec;
108 typedef StableVec::const_iterator SVIter;
109
110 // Cheap version of is_permutation
111 // Builds a set of buckets for each of the key values.
112 // Sums all the payloads.
113 // Not 100% perfect, but _way_ faster
is_permutation(SVIter first1,SVIter last1,SVIter first2)114 bool is_permutation(SVIter first1, SVIter last1, SVIter first2)
115 {
116 size_t xBuckets[256] = {0};
117 size_t xPayloads[256] = {0};
118 size_t yBuckets[256] = {0};
119 size_t yPayloads[256] = {0};
120
121 for (; first1 != last1; ++first1, ++first2)
122 {
123 xBuckets [first1->key]++;
124 xPayloads[first1->key] += first1->payload;
125
126 yBuckets [first2->key]++;
127 yPayloads[first2->key] += first2->payload;
128 }
129
130 for (size_t i = 0; i < 256; ++i)
131 {
132 if (xBuckets[i] != yBuckets[i])
133 return false;
134 if (xPayloads[i] != yPayloads[i])
135 return false;
136 }
137
138 return true;
139 }
140
141 template <typename Iter1, typename Iter2>
is_permutation(Iter1 first1,Iter1 last1,Iter2 first2)142 bool is_permutation(Iter1 first1, Iter1 last1, Iter2 first2)
143 {
144 static_assert((std::is_same<typename std::iterator_traits<Iter1>::value_type, uint8_t>::value), "");
145 static_assert((std::is_same<typename std::iterator_traits<Iter2>::value_type, uint8_t>::value), "");
146
147 size_t xBuckets[256] = {0};
148 size_t yBuckets[256] = {0};
149
150 for (; first1 != last1; ++first1, ++first2)
151 {
152 xBuckets [*first1]++;
153 yBuckets [*first2]++;
154 }
155
156 for (size_t i = 0; i < 256; ++i)
157 if (xBuckets[i] != yBuckets[i])
158 return false;
159
160 return true;
161 }
162
163 // == sort ==
sort(const uint8_t * data,size_t size)164 int sort(const uint8_t *data, size_t size)
165 {
166 Vec working(data, data + size);
167 std::sort(working.begin(), working.end());
168
169 if (!std::is_sorted(working.begin(), working.end())) return 1;
170 if (!fuzzing::is_permutation(data, data + size, working.cbegin())) return 99;
171 return 0;
172 }
173
174
175 // == stable_sort ==
stable_sort(const uint8_t * data,size_t size)176 int stable_sort(const uint8_t *data, size_t size)
177 {
178 StableVec input;
179 for (size_t i = 0; i < size; ++i)
180 input.push_back(stable_test(data[i], i));
181 StableVec working = input;
182 std::stable_sort(working.begin(), working.end(), key_less());
183
184 if (!std::is_sorted(working.begin(), working.end(), key_less())) return 1;
185 auto iter = working.begin();
186 while (iter != working.end())
187 {
188 auto range = std::equal_range(iter, working.end(), *iter, key_less());
189 if (!std::is_sorted(range.first, range.second, total_less())) return 2;
190 iter = range.second;
191 }
192 if (!fuzzing::is_permutation(input.cbegin(), input.cend(), working.cbegin())) return 99;
193 return 0;
194 }
195
196 // == partition ==
partition(const uint8_t * data,size_t size)197 int partition(const uint8_t *data, size_t size)
198 {
199 Vec working(data, data + size);
200 auto iter = std::partition(working.begin(), working.end(), is_even<uint8_t>());
201
202 if (!std::all_of (working.begin(), iter, is_even<uint8_t>())) return 1;
203 if (!std::none_of(iter, working.end(), is_even<uint8_t>())) return 2;
204 if (!fuzzing::is_permutation(data, data + size, working.cbegin())) return 99;
205 return 0;
206 }
207
208
209 // == partition_copy ==
partition_copy(const uint8_t * data,size_t size)210 int partition_copy(const uint8_t *data, size_t size)
211 {
212 Vec v1, v2;
213 auto iter = std::partition_copy(data, data + size,
214 std::back_inserter<Vec>(v1), std::back_inserter<Vec>(v2),
215 is_even<uint8_t>());
216
217 // The two vectors should add up to the original size
218 if (v1.size() + v2.size() != size) return 1;
219
220 // All of the even values should be in the first vector, and none in the second
221 if (!std::all_of (v1.begin(), v1.end(), is_even<uint8_t>())) return 2;
222 if (!std::none_of(v2.begin(), v2.end(), is_even<uint8_t>())) return 3;
223
224 // Every value in both vectors has to be in the original
225 for (auto v: v1)
226 if (std::find(data, data + size, v) == data + size) return 4;
227
228 for (auto v: v2)
229 if (std::find(data, data + size, v) == data + size) return 5;
230
231 return 0;
232 }
233
234 // == stable_partition ==
stable_partition(const uint8_t * data,size_t size)235 int stable_partition (const uint8_t *data, size_t size)
236 {
237 StableVec input;
238 for (size_t i = 0; i < size; ++i)
239 input.push_back(stable_test(data[i], i));
240 StableVec working = input;
241 auto iter = std::stable_partition(working.begin(), working.end(), is_even<stable_test>());
242
243 if (!std::all_of (working.begin(), iter, is_even<stable_test>())) return 1;
244 if (!std::none_of(iter, working.end(), is_even<stable_test>())) return 2;
245 if (!std::is_sorted(working.begin(), iter, payload_less())) return 3;
246 if (!std::is_sorted(iter, working.end(), payload_less())) return 4;
247 if (!fuzzing::is_permutation(input.cbegin(), input.cend(), working.cbegin())) return 99;
248 return 0;
249 }
250
251 // == nth_element ==
252 // use the first element as a position into the data
nth_element(const uint8_t * data,size_t size)253 int nth_element (const uint8_t *data, size_t size)
254 {
255 if (size <= 1) return 0;
256 const size_t partition_point = data[0] % size;
257 Vec working(data + 1, data + size);
258 const auto partition_iter = working.begin() + partition_point;
259 std::nth_element(working.begin(), partition_iter, working.end());
260
261 // nth may be the end iterator, in this case nth_element has no effect.
262 if (partition_iter == working.end())
263 {
264 if (!std::equal(data + 1, data + size, working.begin())) return 98;
265 }
266 else
267 {
268 const uint8_t nth = *partition_iter;
269 if (!std::all_of(working.begin(), partition_iter, [=](uint8_t v) { return v <= nth; }))
270 return 1;
271 if (!std::all_of(partition_iter, working.end(), [=](uint8_t v) { return v >= nth; }))
272 return 2;
273 if (!fuzzing::is_permutation(data + 1, data + size, working.cbegin())) return 99;
274 }
275
276 return 0;
277 }
278
279 // == partial_sort ==
280 // use the first element as a position into the data
partial_sort(const uint8_t * data,size_t size)281 int partial_sort (const uint8_t *data, size_t size)
282 {
283 if (size <= 1) return 0;
284 const size_t sort_point = data[0] % size;
285 Vec working(data + 1, data + size);
286 const auto sort_iter = working.begin() + sort_point;
287 std::partial_sort(working.begin(), sort_iter, working.end());
288
289 if (sort_iter != working.end())
290 {
291 const uint8_t nth = *std::min_element(sort_iter, working.end());
292 if (!std::all_of(working.begin(), sort_iter, [=](uint8_t v) { return v <= nth; }))
293 return 1;
294 if (!std::all_of(sort_iter, working.end(), [=](uint8_t v) { return v >= nth; }))
295 return 2;
296 }
297 if (!std::is_sorted(working.begin(), sort_iter)) return 3;
298 if (!fuzzing::is_permutation(data + 1, data + size, working.cbegin())) return 99;
299
300 return 0;
301 }
302
303
304 // == partial_sort_copy ==
305 // use the first element as a count
partial_sort_copy(const uint8_t * data,size_t size)306 int partial_sort_copy (const uint8_t *data, size_t size)
307 {
308 if (size <= 1) return 0;
309 const size_t num_results = data[0] % size;
310 Vec results(num_results);
311 (void) std::partial_sort_copy(data + 1, data + size, results.begin(), results.end());
312
313 // The results have to be sorted
314 if (!std::is_sorted(results.begin(), results.end())) return 1;
315 // All the values in results have to be in the original data
316 for (auto v: results)
317 if (std::find(data + 1, data + size, v) == data + size) return 2;
318
319 // The things in results have to be the smallest N in the original data
320 Vec sorted(data + 1, data + size);
321 std::sort(sorted.begin(), sorted.end());
322 if (!std::equal(results.begin(), results.end(), sorted.begin())) return 3;
323 return 0;
324 }
325
326 // The second sequence has been "uniqued"
327 template <typename Iter1, typename Iter2>
compare_unique(Iter1 first1,Iter1 last1,Iter2 first2,Iter2 last2)328 static bool compare_unique(Iter1 first1, Iter1 last1, Iter2 first2, Iter2 last2)
329 {
330 assert(first1 != last1 && first2 != last2);
331 if (*first1 != *first2) return false;
332
333 uint8_t last_value = *first1;
334 ++first1; ++first2;
335 while(first1 != last1 && first2 != last2)
336 {
337 // Skip over dups in the first sequence
338 while (*first1 == last_value)
339 if (++first1 == last1) return false;
340 if (*first1 != *first2) return false;
341 last_value = *first1;
342 ++first1; ++first2;
343 }
344
345 // Still stuff left in the 'uniqued' sequence - oops
346 if (first1 == last1 && first2 != last2) return false;
347
348 // Still stuff left in the original sequence - better be all the same
349 while (first1 != last1)
350 {
351 if (*first1 != last_value) return false;
352 ++first1;
353 }
354 return true;
355 }
356
357 // == unique ==
unique(const uint8_t * data,size_t size)358 int unique (const uint8_t *data, size_t size)
359 {
360 Vec working(data, data + size);
361 std::sort(working.begin(), working.end());
362 Vec results = working;
363 Vec::iterator new_end = std::unique(results.begin(), results.end());
364 Vec::iterator it; // scratch iterator
365
366 // Check the size of the unique'd sequence.
367 // it should only be zero if the input sequence was empty.
368 if (results.begin() == new_end)
369 return working.size() == 0 ? 0 : 1;
370
371 // 'results' is sorted
372 if (!std::is_sorted(results.begin(), new_end)) return 2;
373
374 // All the elements in 'results' must be different
375 it = results.begin();
376 uint8_t prev_value = *it++;
377 for (; it != new_end; ++it)
378 {
379 if (*it == prev_value) return 3;
380 prev_value = *it;
381 }
382
383 // Every element in 'results' must be in 'working'
384 for (it = results.begin(); it != new_end; ++it)
385 if (std::find(working.begin(), working.end(), *it) == working.end())
386 return 4;
387
388 // Every element in 'working' must be in 'results'
389 for (auto v : working)
390 if (std::find(results.begin(), new_end, v) == new_end)
391 return 5;
392
393 return 0;
394 }
395
396 // == unique_copy ==
unique_copy(const uint8_t * data,size_t size)397 int unique_copy (const uint8_t *data, size_t size)
398 {
399 Vec working(data, data + size);
400 std::sort(working.begin(), working.end());
401 Vec results;
402 (void) std::unique_copy(working.begin(), working.end(),
403 std::back_inserter<Vec>(results));
404 Vec::iterator it; // scratch iterator
405
406 // Check the size of the unique'd sequence.
407 // it should only be zero if the input sequence was empty.
408 if (results.size() == 0)
409 return working.size() == 0 ? 0 : 1;
410
411 // 'results' is sorted
412 if (!std::is_sorted(results.begin(), results.end())) return 2;
413
414 // All the elements in 'results' must be different
415 it = results.begin();
416 uint8_t prev_value = *it++;
417 for (; it != results.end(); ++it)
418 {
419 if (*it == prev_value) return 3;
420 prev_value = *it;
421 }
422
423 // Every element in 'results' must be in 'working'
424 for (auto v : results)
425 if (std::find(working.begin(), working.end(), v) == working.end())
426 return 4;
427
428 // Every element in 'working' must be in 'results'
429 for (auto v : working)
430 if (std::find(results.begin(), results.end(), v) == results.end())
431 return 5;
432
433 return 0;
434 }
435
436
437 // -- regex fuzzers
regex_helper(const uint8_t * data,size_t size,std::regex::flag_type flag)438 static int regex_helper(const uint8_t *data, size_t size, std::regex::flag_type flag)
439 {
440 if (size > 0)
441 {
442 try
443 {
444 std::string s((const char *)data, size);
445 std::regex re(s, flag);
446 return std::regex_match(s, re) ? 1 : 0;
447 }
448 catch (std::regex_error &ex) {}
449 }
450 return 0;
451 }
452
453
regex_ECMAScript(const uint8_t * data,size_t size)454 int regex_ECMAScript (const uint8_t *data, size_t size)
455 {
456 (void) regex_helper(data, size, std::regex_constants::ECMAScript);
457 return 0;
458 }
459
regex_POSIX(const uint8_t * data,size_t size)460 int regex_POSIX (const uint8_t *data, size_t size)
461 {
462 (void) regex_helper(data, size, std::regex_constants::basic);
463 return 0;
464 }
465
regex_extended(const uint8_t * data,size_t size)466 int regex_extended (const uint8_t *data, size_t size)
467 {
468 (void) regex_helper(data, size, std::regex_constants::extended);
469 return 0;
470 }
471
regex_awk(const uint8_t * data,size_t size)472 int regex_awk (const uint8_t *data, size_t size)
473 {
474 (void) regex_helper(data, size, std::regex_constants::awk);
475 return 0;
476 }
477
regex_grep(const uint8_t * data,size_t size)478 int regex_grep (const uint8_t *data, size_t size)
479 {
480 (void) regex_helper(data, size, std::regex_constants::grep);
481 return 0;
482 }
483
regex_egrep(const uint8_t * data,size_t size)484 int regex_egrep (const uint8_t *data, size_t size)
485 {
486 (void) regex_helper(data, size, std::regex_constants::egrep);
487 return 0;
488 }
489
490 // -- heap fuzzers
make_heap(const uint8_t * data,size_t size)491 int make_heap (const uint8_t *data, size_t size)
492 {
493 Vec working(data, data + size);
494 std::make_heap(working.begin(), working.end());
495
496 if (!std::is_heap(working.begin(), working.end())) return 1;
497 if (!fuzzing::is_permutation(data, data + size, working.cbegin())) return 99;
498 return 0;
499 }
500
push_heap(const uint8_t * data,size_t size)501 int push_heap (const uint8_t *data, size_t size)
502 {
503 if (size < 2) return 0;
504
505 // Make a heap from the first half of the data
506 Vec working(data, data + size);
507 auto iter = working.begin() + (size / 2);
508 std::make_heap(working.begin(), iter);
509 if (!std::is_heap(working.begin(), iter)) return 1;
510
511 // Now push the rest onto the heap, one at a time
512 ++iter;
513 for (; iter != working.end(); ++iter) {
514 std::push_heap(working.begin(), iter);
515 if (!std::is_heap(working.begin(), iter)) return 2;
516 }
517
518 if (!fuzzing::is_permutation(data, data + size, working.cbegin())) return 99;
519 return 0;
520 }
521
pop_heap(const uint8_t * data,size_t size)522 int pop_heap (const uint8_t *data, size_t size)
523 {
524 if (size < 2) return 0;
525 Vec working(data, data + size);
526 std::make_heap(working.begin(), working.end());
527
528 // Pop things off, one at a time
529 auto iter = --working.end();
530 while (iter != working.begin()) {
531 std::pop_heap(working.begin(), iter);
532 if (!std::is_heap(working.begin(), --iter)) return 2;
533 }
534
535 return 0;
536 }
537
538
539 // -- search fuzzers
search(const uint8_t * data,size_t size)540 int search (const uint8_t *data, size_t size)
541 {
542 if (size < 2) return 0;
543
544 const size_t pat_size = data[0] * (size - 1) / std::numeric_limits<uint8_t>::max();
545 assert(pat_size <= size - 1);
546 const uint8_t *pat_begin = data + 1;
547 const uint8_t *pat_end = pat_begin + pat_size;
548 const uint8_t *data_end = data + size;
549 assert(pat_end <= data_end);
550 // std::cerr << "data[0] = " << size_t(data[0]) << " ";
551 // std::cerr << "Pattern size = " << pat_size << "; corpus is " << size - 1 << std::endl;
552 auto it = std::search(pat_end, data_end, pat_begin, pat_end);
553 if (it != data_end) // not found
554 if (!std::equal(pat_begin, pat_end, it))
555 return 1;
556 return 0;
557 }
558
559 template <typename S>
search_helper(const uint8_t * data,size_t size)560 static int search_helper (const uint8_t *data, size_t size)
561 {
562 if (size < 2) return 0;
563
564 const size_t pat_size = data[0] * (size - 1) / std::numeric_limits<uint8_t>::max();
565 const uint8_t *pat_begin = data + 1;
566 const uint8_t *pat_end = pat_begin + pat_size;
567 const uint8_t *data_end = data + size;
568
569 auto it = std::search(pat_end, data_end, S(pat_begin, pat_end));
570 if (it != data_end) // not found
571 if (!std::equal(pat_begin, pat_end, it))
572 return 1;
573 return 0;
574 }
575
576 // These are still in std::experimental
577 // int search_boyer_moore (const uint8_t *data, size_t size)
578 // {
579 // return search_helper<std::boyer_moore_searcher<const uint8_t *>>(data, size);
580 // }
581 //
582 // int search_boyer_moore_horspool (const uint8_t *data, size_t size)
583 // {
584 // return search_helper<std::boyer_moore_horspool_searcher<const uint8_t *>>(data, size);
585 // }
586
587
588 // -- set operation fuzzers
589 template <typename S>
set_helper(const uint8_t * data,size_t size,Vec & v1,Vec & v2)590 static void set_helper (const uint8_t *data, size_t size, Vec &v1, Vec &v2)
591 {
592 assert(size > 1);
593
594 const size_t pat_size = data[0] * (size - 1) / std::numeric_limits<uint8_t>::max();
595 const uint8_t *pat_begin = data + 1;
596 const uint8_t *pat_end = pat_begin + pat_size;
597 const uint8_t *data_end = data + size;
598 v1.assign(pat_begin, pat_end);
599 v2.assign(pat_end, data_end);
600
601 std::sort(v1.begin(), v1.end());
602 std::sort(v2.begin(), v2.end());
603 }
604
605 } // namespace fuzzing
606