xref: /llvm-project/compiler-rt/test/dfsan/custom.cpp (revision 643a2080ec028bd7674206e0f97cbc7d0f132f99)
1 // RUN: %clang_dfsan %s -o %t && env DFSAN_OPTIONS="strict_data_dependencies=0" %run %t
2 // RUN: %clang_dfsan -DSTRICT_DATA_DEPENDENCIES %s -o %t && %run %t
3 // RUN: %clang_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 -mllvm -dfsan-combine-pointer-labels-on-load=false -DSTRICT_DATA_DEPENDENCIES %s -o %t && %run %t
4 // RUN: %clang_dfsan -DORIGIN_TRACKING -mllvm -dfsan-track-origins=1 -mllvm -dfsan-combine-pointer-labels-on-load=false -no-pie %s -o %t && env DFSAN_OPTIONS="strict_data_dependencies=0" %run %t
5 //
6 // Tests custom implementations of various glibc functions.
7 
8 #pragma clang diagnostic ignored "-Wformat-extra-args"
9 
10 #include <sanitizer/dfsan_interface.h>
11 
12 #include <arpa/inet.h>
13 #include <assert.h>
14 #include <fcntl.h>
15 #include <link.h>
16 #include <poll.h>
17 #include <pthread.h>
18 #include <pwd.h>
19 #include <sched.h>
20 #include <signal.h>
21 #include <stdint.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <strings.h>
26 #include <sys/epoll.h>
27 #include <sys/resource.h>
28 #include <sys/select.h>
29 #include <sys/socket.h>
30 #include <sys/stat.h>
31 #include <sys/time.h>
32 #include <sys/types.h>
33 #include <time.h>
34 #include <unistd.h>
35 
36 dfsan_label i_label = 0;
37 dfsan_label j_label = 0;
38 dfsan_label k_label = 0;
39 dfsan_label m_label = 0;
40 dfsan_label n_label = 0;
41 dfsan_label i_j_label = 0;
42 
43 #define ASSERT_ZERO_LABEL(data) \
44   assert(0 == dfsan_get_label((long) (data)))
45 
46 #define ASSERT_READ_ZERO_LABEL(ptr, size) \
47   assert(0 == dfsan_read_label(ptr, size))
48 
49 #define ASSERT_LABEL(data, label) \
50   assert(label == dfsan_get_label((long) (data)))
51 
52 #define ASSERT_READ_LABEL(ptr, size, label) \
53   assert(label == dfsan_read_label(ptr, size))
54 
55 #ifdef ORIGIN_TRACKING
56 #define ASSERT_ZERO_ORIGIN(data) \
57   assert(0 == dfsan_get_origin((long)(data)))
58 #else
59 #define ASSERT_ZERO_ORIGIN(data)
60 #endif
61 
62 #ifdef ORIGIN_TRACKING
63 #define ASSERT_ZERO_ORIGINS(ptr, size)                       \
64   for (int i = 0; i < size; ++i) {                           \
65     assert(0 == dfsan_get_origin((long)(((char *)ptr)[i]))); \
66   }
67 #else
68 #define ASSERT_ZERO_ORIGINS(ptr, size)
69 #endif
70 
71 #ifdef ORIGIN_TRACKING
72 #define ASSERT_ORIGIN(data, origin) \
73   assert(origin == dfsan_get_origin((long)(data)))
74 #else
75 #define ASSERT_ORIGIN(data, origin)
76 #endif
77 
78 #ifdef ORIGIN_TRACKING
79 #define ASSERT_ORIGINS(ptr, size, origin)                         \
80   for (int i = 0; i < size; ++i) {                                \
81     assert(origin == dfsan_get_origin((long)(((char *)ptr)[i]))); \
82   }
83 #else
84 #define ASSERT_ORIGINS(ptr, size, origin)
85 #endif
86 
87 #ifdef ORIGIN_TRACKING
88 #define ASSERT_INIT_ORIGIN(ptr, origin) \
89   assert(origin == dfsan_get_init_origin(ptr))
90 #else
91 #define ASSERT_INIT_ORIGIN(ptr, origin)
92 #endif
93 
94 #ifdef ORIGIN_TRACKING
95 #define ASSERT_INIT_ORIGIN_EQ_ORIGIN(ptr, data) \
96   assert(dfsan_get_origin((long)(data)) == dfsan_get_init_origin(ptr))
97 #else
98 #define ASSERT_INIT_ORIGIN_EQ_ORIGIN(ptr, data)
99 #endif
100 
101 #ifdef ORIGIN_TRACKING
102 #define ASSERT_INIT_ORIGINS(ptr, size, origin)                  \
103   for (int i = 0; i < size; ++i) {                              \
104     assert(origin == dfsan_get_init_origin(&((char *)ptr)[i])); \
105   }
106 #else
107 #define ASSERT_INIT_ORIGINS(ptr, size, origin)
108 #endif
109 
110 #ifdef ORIGIN_TRACKING
111 #define ASSERT_EQ_ORIGIN(data1, data2) \
112   assert(dfsan_get_origin((long)(data1)) == dfsan_get_origin((long)(data2)))
113 #else
114 #define ASSERT_EQ_ORIGIN(data1, data2)
115 #endif
116 
117 #ifdef ORIGIN_TRACKING
118 #define DEFINE_AND_SAVE_ORIGINS(val)    \
119   dfsan_origin val##_o[sizeof(val)];    \
120   for (int i = 0; i < sizeof(val); ++i) \
121     val##_o[i] = dfsan_get_origin((long)(((char *)(&val))[i]));
122 #else
123 #define DEFINE_AND_SAVE_ORIGINS(val)
124 #endif
125 
126 #ifdef ORIGIN_TRACKING
127 #define SAVE_ORIGINS(val)               \
128   for (int i = 0; i < sizeof(val); ++i) \
129     val##_o[i] = dfsan_get_origin((long)(((char *)(&val))[i]));
130 #else
131 #define SAVE_ORIGINS(val)
132 #endif
133 
134 #ifdef ORIGIN_TRACKING
135 #define ASSERT_SAVED_ORIGINS(val)       \
136   for (int i = 0; i < sizeof(val); ++i) \
137     ASSERT_ORIGIN(((char *)(&val))[i], val##_o[i]);
138 #else
139 #define ASSERT_SAVED_ORIGINS(val)
140 #endif
141 
142 #ifdef ORIGIN_TRACKING
143 #define DEFINE_AND_SAVE_N_ORIGINS(val, n) \
144   dfsan_origin val##_o[n];                \
145   for (int i = 0; i < n; ++i)             \
146     val##_o[i] = dfsan_get_origin((long)(val[i]));
147 #else
148 #define DEFINE_AND_SAVE_N_ORIGINS(val, n)
149 #endif
150 
151 #ifdef ORIGIN_TRACKING
152 #define ASSERT_SAVED_N_ORIGINS(val, n) \
153   for (int i = 0; i < n; ++i)          \
154     ASSERT_ORIGIN(val[i], val##_o[i]);
155 #else
156 #define ASSERT_SAVED_N_ORIGINS(val, n)
157 #endif
158 
159 #if !defined(__GLIBC_PREREQ)
160 #  define __GLIBC_PREREQ(a, b) 0
161 #endif
162 
163 void test_stat() {
164   int i = 1;
165   dfsan_set_label(i_label, &i, sizeof(i));
166 
167   struct stat s;
168   s.st_dev = i;
169   DEFINE_AND_SAVE_ORIGINS(s)
170   int ret = stat("/", &s);
171   assert(0 == ret);
172   ASSERT_ZERO_LABEL(ret);
173   ASSERT_ZERO_LABEL(s.st_dev);
174   ASSERT_SAVED_ORIGINS(s)
175 
176   s.st_dev = i;
177   SAVE_ORIGINS(s)
178   ret = stat("/nonexistent_581cb021aba7", &s);
179   assert(-1 == ret);
180   ASSERT_ZERO_LABEL(ret);
181   ASSERT_LABEL(s.st_dev, i_label);
182   ASSERT_SAVED_ORIGINS(s)
183 }
184 
185 void test_fstat() {
186   int i = 1;
187   dfsan_set_label(i_label, &i, sizeof(i));
188 
189   struct stat s;
190   int fd = open("/dev/zero", O_RDONLY);
191   s.st_dev = i;
192   DEFINE_AND_SAVE_ORIGINS(s)
193   int rv = fstat(fd, &s);
194   assert(0 == rv);
195   ASSERT_ZERO_LABEL(rv);
196   ASSERT_ZERO_LABEL(s.st_dev);
197   ASSERT_SAVED_ORIGINS(s)
198 }
199 
200 void test_memcmp() {
201   char str1[] = "str1", str2[] = "str2";
202   dfsan_set_label(i_label, &str1[3], 1);
203   dfsan_set_label(j_label, &str2[3], 1);
204 
205   int rv = memcmp(str1, str2, sizeof(str1));
206   assert(rv < 0);
207 #ifdef STRICT_DATA_DEPENDENCIES
208   ASSERT_ZERO_LABEL(rv);
209 #else
210   ASSERT_LABEL(rv, i_j_label);
211   ASSERT_EQ_ORIGIN(rv, str1[3]);
212 #endif
213 
214   rv = memcmp(str1, str2, sizeof(str1) - 2);
215   assert(rv == 0);
216   ASSERT_ZERO_LABEL(rv);
217 }
218 
219 void test_bcmp() {
220   char str1[] = "str1", str2[] = "str2";
221   dfsan_set_label(i_label, &str1[3], 1);
222   dfsan_set_label(j_label, &str2[3], 1);
223 
224   int rv = bcmp(str1, str2, sizeof(str1));
225   assert(rv != 0);
226 #ifdef STRICT_DATA_DEPENDENCIES
227   ASSERT_ZERO_LABEL(rv);
228 #else
229   ASSERT_LABEL(rv, i_j_label);
230   ASSERT_EQ_ORIGIN(rv, str1[3]);
231 #endif
232 
233   rv = bcmp(str1, str2, sizeof(str1) - 2);
234   assert(rv == 0);
235   ASSERT_ZERO_LABEL(rv);
236 }
237 
238 void test_memcpy() {
239   char str1[] = "str1";
240   char str2[sizeof(str1)];
241   dfsan_set_label(i_label, &str1[3], 1);
242 
243   DEFINE_AND_SAVE_ORIGINS(str1)
244 
245   char *ptr2 = str2;
246   dfsan_set_label(j_label, &ptr2, sizeof(ptr2));
247 
248   void *r = memcpy(ptr2, str1, sizeof(str1));
249   ASSERT_LABEL(r, j_label);
250   ASSERT_EQ_ORIGIN(r, ptr2);
251   assert(0 == memcmp(str2, str1, sizeof(str1)));
252   ASSERT_ZERO_LABEL(str2[0]);
253   ASSERT_LABEL(str2[3], i_label);
254 
255   for (int i = 0; i < sizeof(str2); ++i) {
256     if (!dfsan_get_label(str2[i]))
257       continue;
258     ASSERT_INIT_ORIGIN(&(str2[i]), str1_o[i]);
259   }
260 }
261 
262 void test_memmove() {
263   char str[] = "str1xx";
264   dfsan_set_label(i_label, &str[3], 1);
265 
266   DEFINE_AND_SAVE_ORIGINS(str)
267 
268   char *ptr = str + 2;
269   dfsan_set_label(j_label, &ptr, sizeof(ptr));
270 
271   void *r = memmove(ptr, str, 4);
272   ASSERT_LABEL(r, j_label);
273   ASSERT_EQ_ORIGIN(r, ptr);
274   assert(0 == memcmp(str + 2, "str1", 4));
275   ASSERT_ZERO_LABEL(str[4]);
276   ASSERT_LABEL(str[5], i_label);
277 
278   for (int i = 0; i < 4; ++i) {
279     if (!dfsan_get_label(ptr[i]))
280       continue;
281     ASSERT_INIT_ORIGIN(&(ptr[i]), str_o[i]);
282   }
283 }
284 
285 void test_memset() {
286   char buf[8];
287   int j = 'a';
288   char *ptr = buf;
289   dfsan_set_label(j_label, &j, sizeof(j));
290   dfsan_set_label(k_label, &ptr, sizeof(ptr));
291   void *ret = memset(ptr, j, sizeof(buf));
292   ASSERT_LABEL(ret, k_label);
293   ASSERT_EQ_ORIGIN(ret, ptr);
294   for (int i = 0; i < 8; ++i) {
295     ASSERT_LABEL(buf[i], j_label);
296     ASSERT_EQ_ORIGIN(buf[i], j);
297     assert(buf[i] == 'a');
298   }
299 }
300 
301 void test_strcmp() {
302   char str1[] = "str1", str2[] = "str2";
303   dfsan_set_label(i_label, &str1[3], 1);
304   dfsan_set_label(j_label, &str2[3], 1);
305 
306   int rv = strcmp(str1, str2);
307   assert(rv < 0);
308 #ifdef STRICT_DATA_DEPENDENCIES
309   ASSERT_ZERO_LABEL(rv);
310 #else
311   ASSERT_LABEL(rv, i_j_label);
312   ASSERT_EQ_ORIGIN(rv, str1[3]);
313 #endif
314 
315   rv = strcmp(str1, str1);
316   assert(rv == 0);
317 #ifdef STRICT_DATA_DEPENDENCIES
318   ASSERT_ZERO_LABEL(rv);
319   ASSERT_ZERO_ORIGIN(rv);
320 #else
321   ASSERT_LABEL(rv, i_label);
322   ASSERT_EQ_ORIGIN(rv, str1[3]);
323 #endif
324 }
325 
326 void test_strcat() {
327   char src[] = "world";
328   int volatile x = 0; // buffer to ensure src and dst do not share origins
329   (void)x;
330   char dst[] = "hello \0    ";
331   int volatile y = 0; // buffer to ensure dst and p do not share origins
332   (void)y;
333   char *p = dst;
334   dfsan_set_label(k_label, &p, sizeof(p));
335   dfsan_set_label(i_label, src, sizeof(src));
336   dfsan_set_label(j_label, dst, sizeof(dst));
337   dfsan_origin dst_o = dfsan_get_origin((long)dst[0]);
338   (void)dst_o;
339   char *ret = strcat(p, src);
340 
341   ASSERT_LABEL(ret, k_label);
342   ASSERT_EQ_ORIGIN(ret, p);
343   assert(ret == dst);
344   assert(strcmp(src, dst + 6) == 0);
345   // Origins are assigned for every 4 contiguous 4-aligned bytes. After
346   // appending src to dst, origins of src can overwrite origins of dst if their
347   // application adddresses are within [start_aligned_down, end_aligned_up).
348   // Other origins are not changed.
349   char *start_aligned_down = (char *)(((size_t)(dst + 6)) & ~3UL);
350   char *end_aligned_up = (char *)(((size_t)(dst + 11 + 4)) & ~3UL);
351   for (int i = 0; i < 12; ++i) {
352     if (dst + i < start_aligned_down || dst + i >= end_aligned_up) {
353       ASSERT_INIT_ORIGIN(&dst[i], dst_o);
354     } else {
355       ASSERT_INIT_ORIGIN_EQ_ORIGIN(&dst[i], src[0]);
356     }
357   }
358   for (int i = 0; i < 6; ++i) {
359     ASSERT_LABEL(dst[i], j_label);
360   }
361   for (int i = 6; i < strlen(dst); ++i) {
362     ASSERT_LABEL(dst[i], i_label);
363     assert(dfsan_get_label(dst[i]) == dfsan_get_label(src[i - 6]));
364   }
365   ASSERT_LABEL(dst[11], j_label);
366 }
367 
368 void test_strncat(int n) {
369   char src[] = "world";
370   int volatile x = 0; // buffer to ensure src and dst do not share origins
371   (void)x;
372   char dst[] = "hello \0    ";
373   int volatile y = 0; // buffer to ensure dst and p do not share origins
374   (void)y;
375   char *p = dst;
376   dfsan_set_label(k_label, &p, sizeof(p));
377   dfsan_set_label(i_label, src, sizeof(src));
378   dfsan_set_label(j_label, dst, sizeof(dst));
379   dfsan_origin dst_o = dfsan_get_origin((long)dst[0]);
380   (void)dst_o;
381   char *ret = strncat(p, src, n);
382 
383   ASSERT_LABEL(ret, k_label);
384   ASSERT_EQ_ORIGIN(ret, p);
385   assert(ret == dst);
386   assert(strncmp(src, dst + 6, n) == 0);
387   // Origins are assigned for every 4 contiguous 4-aligned bytes. After
388   // appending src to dst, origins of src can overwrite origins of dst if their
389   // application adddresses are within [start_aligned_down, end_aligned_up).
390   // Other origins are not changed.
391   int pad = n % 4;
392   if (pad)
393     pad = 4 - pad;
394 
395   char *start_aligned_down = (char *)(((size_t)(dst + 6)) & ~3UL);
396   char *end_aligned_up = (char *)(((size_t)(dst + 6 + n + pad)) & ~3UL);
397 
398   for (int i = 0; i < 12; ++i) {
399     if (dst + i < start_aligned_down || dst + i >= end_aligned_up) {
400       ASSERT_INIT_ORIGIN(&dst[i], dst_o);
401     } else {
402       ASSERT_INIT_ORIGIN_EQ_ORIGIN(&dst[i], src[0]);
403     }
404   }
405   for (int i = 0; i < 6; ++i) {
406     ASSERT_LABEL(dst[i], j_label);
407   }
408   for (int i = 6; i < 6 + n; ++i) {
409     ASSERT_LABEL(dst[i], i_label);
410     assert(dfsan_get_label(dst[i]) == dfsan_get_label(src[i - 6]));
411   }
412   for (int i = 6 + n; i < strlen(dst); ++i) {
413     ASSERT_LABEL(dst[i], j_label);
414   }
415   ASSERT_LABEL(dst[11], j_label);
416 }
417 
418 void test_strlen() {
419   char str1[] = "str1";
420   dfsan_set_label(i_label, &str1[3], 1);
421 
422   int rv = strlen(str1);
423   assert(rv == 4);
424 #ifdef STRICT_DATA_DEPENDENCIES
425   ASSERT_ZERO_LABEL(rv);
426 #else
427   ASSERT_LABEL(rv, i_label);
428   ASSERT_EQ_ORIGIN(rv, str1[3]);
429 #endif
430 }
431 
432 void test_strnlen() {
433   char str1[] = "str1";
434   dfsan_set_label(i_label, &str1[3], 1);
435 
436   int maxlen = 4;
437   dfsan_set_label(j_label, &maxlen, sizeof(maxlen));
438 
439   int rv = strnlen(str1, maxlen);
440   assert(rv == 4);
441 #ifdef STRICT_DATA_DEPENDENCIES
442   ASSERT_ZERO_LABEL(rv);
443 #else
444   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
445   ASSERT_EQ_ORIGIN(rv, str1[3]);
446 #endif
447 
448   maxlen = 2;
449   dfsan_set_label(j_label, &maxlen, sizeof(maxlen));
450   rv = strnlen(str1, maxlen);
451   assert(rv == 2);
452 #ifdef STRICT_DATA_DEPENDENCIES
453   ASSERT_ZERO_LABEL(rv);
454 #else
455   ASSERT_LABEL(rv, j_label);
456   ASSERT_EQ_ORIGIN(rv, maxlen);
457 #endif
458 }
459 
460 void test_strdup() {
461   char str1[] = "str1";
462   dfsan_set_label(i_label, &str1[3], 1);
463   DEFINE_AND_SAVE_ORIGINS(str1)
464 
465   char *strd = strdup(str1);
466   ASSERT_ZERO_LABEL(strd);
467   ASSERT_ZERO_LABEL(strd[0]);
468   ASSERT_LABEL(strd[3], i_label);
469 
470   for (int i = 0; i < strlen(strd); ++i) {
471     if (!dfsan_get_label(strd[i]))
472       continue;
473     ASSERT_INIT_ORIGIN(&(strd[i]), str1_o[i]);
474   }
475 
476   free(strd);
477 }
478 
479 void test_strncpy() {
480   char str1[] = "str1";
481   char str2[sizeof(str1)];
482   dfsan_set_label(i_label, &str1[3], 1);
483 
484   char *strd = strncpy(str2, str1, 5);
485   assert(strd == str2);
486   assert(strcmp(str1, str2) == 0);
487   ASSERT_ZERO_LABEL(strd);
488   ASSERT_ZERO_LABEL(strd[0]);
489   ASSERT_ZERO_LABEL(strd[1]);
490   ASSERT_ZERO_LABEL(strd[2]);
491   ASSERT_LABEL(strd[3], i_label);
492   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&(strd[3]), str1[3]);
493 
494   char *p2 = str2;
495   dfsan_set_label(j_label, &p2, sizeof(p2));
496   strd = strncpy(p2, str1, 3);
497   assert(strd == str2);
498   assert(strncmp(str1, str2, 3) == 0);
499   ASSERT_LABEL(strd, j_label);
500   ASSERT_EQ_ORIGIN(strd, p2);
501   // When -dfsan-combine-pointer-labels-on-load is on, strd's label propagates
502   // to strd[i]'s label. When ORIGIN_TRACKING is defined,
503   // -dfsan-combine-pointer-labels-on-load is always off, otherwise the flag
504   // is on by default.
505 #if defined(ORIGIN_TRACKING)
506   ASSERT_ZERO_LABEL(strd[0]);
507   ASSERT_ZERO_LABEL(strd[1]);
508   ASSERT_ZERO_LABEL(strd[2]);
509 #else
510   ASSERT_LABEL(strd[0], j_label);
511   ASSERT_LABEL(strd[1], j_label);
512   ASSERT_LABEL(strd[2], j_label);
513 #endif
514 }
515 
516 void test_strncmp() {
517   char str1[] = "str1", str2[] = "str2";
518   dfsan_set_label(i_label, &str1[3], 1);
519   dfsan_set_label(j_label, &str2[3], 1);
520 
521   int rv = strncmp(str1, str2, sizeof(str1));
522   assert(rv < 0);
523 #ifdef STRICT_DATA_DEPENDENCIES
524   ASSERT_ZERO_LABEL(rv);
525 #else
526   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
527   ASSERT_EQ_ORIGIN(rv, str1[3]);
528 #endif
529 
530   rv = strncmp(str1, str2, 0);
531   assert(rv == 0);
532   ASSERT_ZERO_LABEL(rv);
533 
534   rv = strncmp(str1, str2, 3);
535   assert(rv == 0);
536   ASSERT_ZERO_LABEL(rv);
537 
538   rv = strncmp(str1, str1, 4);
539   assert(rv == 0);
540 #ifdef STRICT_DATA_DEPENDENCIES
541   ASSERT_ZERO_LABEL(rv);
542 #else
543   ASSERT_LABEL(rv, i_label);
544   ASSERT_EQ_ORIGIN(rv, str1[3]);
545 #endif
546 }
547 
548 void test_strcasecmp() {
549   char str1[] = "str1", str2[] = "str2", str3[] = "Str1";
550   dfsan_set_label(i_label, &str1[3], 1);
551   dfsan_set_label(j_label, &str2[3], 1);
552   dfsan_set_label(j_label, &str3[2], 1);
553 
554   int rv = strcasecmp(str1, str2);
555   assert(rv < 0);
556 #ifdef STRICT_DATA_DEPENDENCIES
557   ASSERT_ZERO_LABEL(rv);
558 #else
559   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
560   ASSERT_EQ_ORIGIN(rv, str1[3]);
561 #endif
562 
563   rv = strcasecmp(str1, str3);
564   assert(rv == 0);
565 #ifdef STRICT_DATA_DEPENDENCIES
566   ASSERT_ZERO_LABEL(rv);
567 #else
568   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
569   ASSERT_EQ_ORIGIN(rv, str1[3]);
570 #endif
571 
572   char s1[] = "AbZ";
573   char s2[] = "aBy";
574   dfsan_set_label(i_label, &s1[2], 1);
575   dfsan_set_label(j_label, &s2[2], 1);
576 
577   rv = strcasecmp(s1, s2);
578   assert(rv > 0); // 'Z' > 'y'
579 #ifdef STRICT_DATA_DEPENDENCIES
580   ASSERT_ZERO_LABEL(rv);
581 #else
582   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
583   ASSERT_EQ_ORIGIN(rv, s1[2]);
584 #endif
585 }
586 
587 void test_strncasecmp() {
588   char str1[] = "Str1", str2[] = "str2";
589   dfsan_set_label(i_label, &str1[3], 1);
590   dfsan_set_label(j_label, &str2[3], 1);
591 
592   int rv = strncasecmp(str1, str2, sizeof(str1));
593   assert(rv < 0);
594 #ifdef STRICT_DATA_DEPENDENCIES
595   ASSERT_ZERO_LABEL(rv);
596 #else
597   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
598   ASSERT_EQ_ORIGIN(rv, str1[3]);
599 #endif
600 
601   rv = strncasecmp(str1, str2, 3);
602   assert(rv == 0);
603   ASSERT_ZERO_LABEL(rv);
604 
605   char s1[] = "AbZ";
606   char s2[] = "aBy";
607   dfsan_set_label(i_label, &s1[2], 1);
608   dfsan_set_label(j_label, &s2[2], 1);
609 
610   rv = strncasecmp(s1, s2, 0);
611   assert(rv == 0); // Compare zero chars.
612   ASSERT_ZERO_LABEL(rv);
613 
614   rv = strncasecmp(s1, s2, 1);
615   assert(rv == 0); // 'A' == 'a'
616   ASSERT_ZERO_LABEL(rv);
617 
618   rv = strncasecmp(s1, s2, 2);
619   assert(rv == 0); // 'b' == 'B'
620   ASSERT_ZERO_LABEL(rv);
621 
622   rv = strncasecmp(s1, s2, 3);
623   assert(rv > 0); // 'Z' > 'y'
624 #ifdef STRICT_DATA_DEPENDENCIES
625   ASSERT_ZERO_LABEL(rv);
626 #else
627   ASSERT_LABEL(rv, dfsan_union(i_label, j_label));
628   ASSERT_EQ_ORIGIN(rv, s1[2]);
629 #endif
630 }
631 
632 void test_strchr() {
633   char str1[] = "str1";
634   dfsan_set_label(i_label, &str1[3], 1);
635 
636   char *p1 = str1;
637   char c = 'r';
638   dfsan_set_label(k_label, &c, sizeof(c));
639 
640   char *crv = strchr(p1, c);
641   assert(crv == &str1[2]);
642 #ifdef STRICT_DATA_DEPENDENCIES
643   ASSERT_ZERO_LABEL(crv);
644 #else
645   ASSERT_LABEL(crv, k_label);
646   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, c);
647 #endif
648 
649   dfsan_set_label(j_label, &p1, sizeof(p1));
650   crv = strchr(p1, 'r');
651   assert(crv == &str1[2]);
652   ASSERT_LABEL(crv, j_label);
653   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, p1);
654 
655   crv = strchr(p1, '1');
656   assert(crv == &str1[3]);
657 #ifdef STRICT_DATA_DEPENDENCIES
658   ASSERT_LABEL(crv, j_label);
659   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, p1);
660 #else
661   ASSERT_LABEL(crv, i_j_label);
662   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, str1[3]);
663 #endif
664 
665   crv = strchr(p1, 'x');
666   assert(!crv);
667 #ifdef STRICT_DATA_DEPENDENCIES
668   ASSERT_LABEL(crv, j_label);
669   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, p1);
670 #else
671   ASSERT_LABEL(crv, i_j_label);
672   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, str1[3]);
673 #endif
674 
675   // `man strchr` says:
676   // The terminating null byte is considered part of the string, so that if c
677   // is specified as '\0', these functions return a pointer to the terminator.
678   crv = strchr(p1, '\0');
679   assert(crv == &str1[4]);
680 #ifdef STRICT_DATA_DEPENDENCIES
681   ASSERT_LABEL(crv, j_label);
682   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, p1);
683 #else
684   ASSERT_LABEL(crv, i_j_label);
685   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&crv, str1[3]);
686 #endif
687 }
688 
689 void test_recvmmsg() {
690   int sockfds[2];
691   int ret = socketpair(AF_UNIX, SOCK_DGRAM, 0, sockfds);
692   assert(ret != -1);
693 
694   // Setup messages to send.
695   struct mmsghdr smmsg[2] = {};
696   char sbuf0[] = "abcdefghijkl";
697   struct iovec siov0[2] = {{&sbuf0[0], 4}, {&sbuf0[4], 4}};
698   smmsg[0].msg_hdr.msg_iov = siov0;
699   smmsg[0].msg_hdr.msg_iovlen = 2;
700   char sbuf1[] = "1234567890";
701   struct iovec siov1[1] = {{&sbuf1[0], 7}};
702   smmsg[1].msg_hdr.msg_iov = siov1;
703   smmsg[1].msg_hdr.msg_iovlen = 1;
704 
705   // Send messages.
706   int sent_msgs = sendmmsg(sockfds[0], smmsg, 2, 0);
707   assert(sent_msgs == 2);
708 
709   // Setup receive buffers.
710   struct mmsghdr rmmsg[2] = {};
711   char rbuf0[128];
712   struct iovec riov0[2] = {{&rbuf0[0], 4}, {&rbuf0[4], 4}};
713   rmmsg[0].msg_hdr.msg_iov = riov0;
714   rmmsg[0].msg_hdr.msg_iovlen = 2;
715   char rbuf1[128];
716   struct iovec riov1[1] = {{&rbuf1[0], 16}};
717   rmmsg[1].msg_hdr.msg_iov = riov1;
718   rmmsg[1].msg_hdr.msg_iovlen = 1;
719   struct timespec timeout = {1, 1};
720   dfsan_set_label(i_label, rbuf0, sizeof(rbuf0));
721   dfsan_set_label(i_label, rbuf1, sizeof(rbuf1));
722   dfsan_set_label(i_label, &rmmsg[0].msg_len, sizeof(rmmsg[0].msg_len));
723   dfsan_set_label(i_label, &rmmsg[1].msg_len, sizeof(rmmsg[1].msg_len));
724   dfsan_set_label(i_label, &timeout, sizeof(timeout));
725 
726   dfsan_origin msg_len0_o = dfsan_get_origin((long)(rmmsg[0].msg_len));
727   dfsan_origin msg_len1_o = dfsan_get_origin((long)(rmmsg[1].msg_len));
728 #ifndef ORIGIN_TRACKING
729   (void)msg_len0_o;
730   (void)msg_len1_o;
731 #endif
732 
733   // Receive messages and check labels.
734   int received_msgs = recvmmsg(sockfds[1], rmmsg, 2, 0, &timeout);
735   assert(received_msgs == sent_msgs);
736   assert(rmmsg[0].msg_len == smmsg[0].msg_len);
737   assert(rmmsg[1].msg_len == smmsg[1].msg_len);
738   assert(memcmp(sbuf0, rbuf0, 8) == 0);
739   assert(memcmp(sbuf1, rbuf1, 7) == 0);
740   ASSERT_ZERO_LABEL(received_msgs);
741   ASSERT_ZERO_LABEL(rmmsg[0].msg_len);
742   ASSERT_ZERO_LABEL(rmmsg[1].msg_len);
743   ASSERT_READ_ZERO_LABEL(&rbuf0[0], 8);
744   ASSERT_READ_LABEL(&rbuf0[8], 1, i_label);
745   ASSERT_READ_ZERO_LABEL(&rbuf1[0], 7);
746   ASSERT_READ_LABEL(&rbuf1[7], 1, i_label);
747   ASSERT_LABEL(timeout.tv_sec, i_label);
748   ASSERT_LABEL(timeout.tv_nsec, i_label);
749 
750   ASSERT_ORIGIN((long)(rmmsg[0].msg_len), msg_len0_o);
751   ASSERT_ORIGIN((long)(rmmsg[1].msg_len), msg_len1_o);
752 
753   close(sockfds[0]);
754   close(sockfds[1]);
755 }
756 
757 void test_recvmsg() {
758   int sockfds[2];
759   int ret = socketpair(AF_UNIX, SOCK_DGRAM, 0, sockfds);
760   assert(ret != -1);
761 
762   char sbuf[] = "abcdefghijkl";
763   struct iovec siovs[2] = {{&sbuf[0], 4}, {&sbuf[4], 4}};
764   struct msghdr smsg = {};
765   smsg.msg_iov = siovs;
766   smsg.msg_iovlen = 2;
767 
768   ssize_t sent = sendmsg(sockfds[0], &smsg, 0);
769   assert(sent > 0);
770 
771   {
772     char rpbuf[2];
773     struct iovec peek_iov;
774     peek_iov.iov_base = rpbuf;
775     peek_iov.iov_len = 2;
776 
777     struct msghdr peek_header = {};
778     peek_header.msg_iov = &peek_iov;
779     peek_header.msg_iovlen = 1;
780 
781     dfsan_set_label(i_label, rpbuf, sizeof(rpbuf));
782     dfsan_set_label(i_label, &peek_header, sizeof(peek_header));
783 
784     DEFINE_AND_SAVE_ORIGINS(peek_header)
785 
786     ssize_t received = recvmsg(sockfds[1], &peek_header, MSG_PEEK | MSG_TRUNC);
787     assert(received == sent);
788     assert(memcmp(sbuf, rpbuf, 2) == 0);
789     ASSERT_ZERO_LABEL(received);
790     ASSERT_READ_ZERO_LABEL(&peek_header, sizeof(peek_header));
791     ASSERT_READ_ZERO_LABEL(&rpbuf[0], 0);
792 
793     ASSERT_SAVED_ORIGINS(peek_header)
794   }
795 
796   {
797     char rbuf[128];
798     struct iovec riovs[2] = {{&rbuf[0], 4}, {&rbuf[4], 4}};
799     struct msghdr rmsg = {};
800     rmsg.msg_iov = riovs;
801     rmsg.msg_iovlen = 2;
802 
803     dfsan_set_label(i_label, rbuf, sizeof(rbuf));
804     dfsan_set_label(i_label, &rmsg, sizeof(rmsg));
805 
806     DEFINE_AND_SAVE_ORIGINS(rmsg)
807 
808     ssize_t received = recvmsg(sockfds[1], &rmsg, 0);
809     assert(received == sent);
810     assert(memcmp(sbuf, rbuf, 8) == 0);
811     ASSERT_ZERO_LABEL(received);
812     ASSERT_READ_ZERO_LABEL(&rmsg, sizeof(rmsg));
813     ASSERT_READ_ZERO_LABEL(&rbuf[0], 8);
814     ASSERT_READ_LABEL(&rbuf[8], 1, i_label);
815 
816     ASSERT_SAVED_ORIGINS(rmsg)
817   }
818 
819   close(sockfds[0]);
820   close(sockfds[1]);
821 }
822 
823 void test_read() {
824   char buf[16];
825   dfsan_set_label(i_label, buf, 1);
826   dfsan_set_label(j_label, buf + 15, 1);
827 
828   DEFINE_AND_SAVE_ORIGINS(buf)
829   ASSERT_LABEL(buf[0], i_label);
830   ASSERT_LABEL(buf[15], j_label);
831 
832   int fd = open("/dev/zero", O_RDONLY);
833   int rv = read(fd, buf, sizeof(buf));
834   assert(rv == sizeof(buf));
835   ASSERT_ZERO_LABEL(rv);
836   ASSERT_ZERO_LABEL(buf[0]);
837   ASSERT_ZERO_LABEL(buf[15]);
838   ASSERT_SAVED_ORIGINS(buf)
839   close(fd);
840 }
841 
842 void test_pread() {
843   char buf[16];
844   dfsan_set_label(i_label, buf, 1);
845   dfsan_set_label(j_label, buf + 15, 1);
846 
847   DEFINE_AND_SAVE_ORIGINS(buf)
848   ASSERT_LABEL(buf[0], i_label);
849   ASSERT_LABEL(buf[15], j_label);
850 
851   int fd = open("/bin/sh", O_RDONLY);
852   int rv = pread(fd, buf, sizeof(buf), 0);
853   assert(rv == sizeof(buf));
854   ASSERT_ZERO_LABEL(rv);
855   ASSERT_ZERO_LABEL(buf[0]);
856   ASSERT_ZERO_LABEL(buf[15]);
857   ASSERT_SAVED_ORIGINS(buf)
858   close(fd);
859 }
860 
861 void test_dlopen() {
862   void *map = dlopen(NULL, RTLD_NOW);
863   assert(map);
864   ASSERT_ZERO_LABEL(map);
865   dlclose(map);
866   map = dlopen("/nonexistent", RTLD_NOW);
867   assert(!map);
868   ASSERT_ZERO_LABEL(map);
869 }
870 
871 void test_clock_gettime() {
872   struct timespec tp;
873   dfsan_set_label(j_label, ((char *)&tp) + 3, 1);
874   dfsan_origin origin = dfsan_get_origin((long)(((char *)&tp)[3]));
875 #ifndef ORIGIN_TRACKING
876   (void)origin;
877 #endif
878   int t = clock_gettime(CLOCK_REALTIME, &tp);
879   assert(t == 0);
880   ASSERT_ZERO_LABEL(t);
881   ASSERT_ZERO_LABEL(((char *)&tp)[3]);
882   ASSERT_ORIGIN(((char *)&tp)[3], origin);
883 }
884 
885 void test_ctime_r() {
886   char *buf = (char*) malloc(64);
887   time_t t = 0;
888 
889   DEFINE_AND_SAVE_ORIGINS(buf)
890   dfsan_origin t_o = dfsan_get_origin((long)t);
891 
892   char *ret = ctime_r(&t, buf);
893   ASSERT_ZERO_LABEL(ret);
894   assert(buf == ret);
895   ASSERT_READ_ZERO_LABEL(buf, strlen(buf) + 1);
896   ASSERT_SAVED_ORIGINS(buf)
897 
898   dfsan_set_label(i_label, &t, sizeof(t));
899   t_o = dfsan_get_origin((long)t);
900   ret = ctime_r(&t, buf);
901   ASSERT_ZERO_LABEL(ret);
902   ASSERT_READ_LABEL(buf, strlen(buf) + 1, i_label);
903   for (int i = 0; i < strlen(buf) + 1; ++i)
904     ASSERT_ORIGIN(buf[i], t_o);
905 
906   t = 0;
907   dfsan_set_label(j_label, &buf, sizeof(&buf));
908   dfsan_origin buf_ptr_o = dfsan_get_origin((long)buf);
909 #ifndef ORIGIN_TRACKING
910   (void)buf_ptr_o;
911 #endif
912   ret = ctime_r(&t, buf);
913   ASSERT_LABEL(ret, j_label);
914   ASSERT_ORIGIN(ret, buf_ptr_o);
915   ASSERT_READ_ZERO_LABEL(buf, strlen(buf) + 1);
916   for (int i = 0; i < strlen(buf) + 1; ++i)
917     ASSERT_ORIGIN(buf[i], t_o);
918 }
919 
920 static int write_callback_count = 0;
921 static int last_fd;
922 static const unsigned char *last_buf;
923 static size_t last_count;
924 
925 void write_callback(int fd, const void *buf, size_t count) {
926   write_callback_count++;
927 
928   last_fd = fd;
929   last_buf = (const unsigned char*) buf;
930   last_count = count;
931 }
932 
933 void test_dfsan_set_write_callback() {
934   char a_buf[] = "Sample chars";
935   int a_buf_len = strlen(a_buf);
936 
937   int fd = open("/dev/null", O_WRONLY);
938 
939   dfsan_set_write_callback(write_callback);
940 
941   write_callback_count = 0;
942 
943   DEFINE_AND_SAVE_ORIGINS(a_buf)
944 
945   // Callback should be invoked on every call to write().
946   int res = write(fd, a_buf, a_buf_len);
947   assert(write_callback_count == 1);
948   ASSERT_READ_ZERO_LABEL(&res, sizeof(res));
949   ASSERT_READ_ZERO_LABEL(&last_fd, sizeof(last_fd));
950   ASSERT_READ_ZERO_LABEL(last_buf, sizeof(last_buf));
951 
952   for (int i = 0; i < a_buf_len; ++i)
953     ASSERT_ORIGIN(last_buf[i], a_buf_o[i]);
954 
955   ASSERT_ZERO_ORIGINS(&last_count, sizeof(last_count));
956   last_fd = 0;
957   last_buf = 0;
958   last_count = 0;
959 
960   char b_buf[] = "Other chars";
961   int b_buf_len = strlen(b_buf);
962   // Create a separate variable so we can taint the pointer.
963   // We would always get a shadow of 0 for b_buf because it is a constant.
964   const unsigned char *buf = (const unsigned char *)b_buf;
965 
966   // Add a label to write() arguments.  Check that the labels are readable from
967   // the values passed to the callback.
968   dfsan_set_label(i_label, &fd, sizeof(fd));
969   dfsan_set_label(j_label, &buf, sizeof(buf)); // ptr
970   dfsan_set_label(k_label, &(b_buf[3]), 1);    // content
971   dfsan_set_label(m_label, &b_buf_len, sizeof(b_buf_len));
972 
973   dfsan_origin fd_o = dfsan_get_origin((long)fd);
974   dfsan_origin b_buf3_o = dfsan_get_origin((long)(b_buf[3]));
975   dfsan_origin b_buf_len_o = dfsan_get_origin((long)b_buf_len);
976 #ifndef ORIGIN_TRACKING
977   (void)fd_o;
978   (void)b_buf3_o;
979   (void)b_buf_len_o;
980 #endif
981   DEFINE_AND_SAVE_ORIGINS(b_buf)
982 
983   res = write(fd, buf, b_buf_len);
984   assert(write_callback_count == 2);
985   assert(last_fd == fd);
986   assert(last_buf == (const unsigned char *)b_buf);
987   assert(last_count == b_buf_len);
988 
989   ASSERT_READ_ZERO_LABEL(&res, sizeof(res));
990   ASSERT_READ_LABEL(&last_fd, sizeof(last_fd), i_label);
991   ASSERT_READ_LABEL(&last_buf, sizeof(&last_buf), j_label);      // ptr
992   ASSERT_READ_LABEL(last_buf, last_count, k_label);              // content
993   ASSERT_READ_LABEL(&last_buf[3], sizeof(last_buf[3]), k_label); // content
994   ASSERT_READ_LABEL(&last_count, sizeof(last_count), m_label);
995   ASSERT_ZERO_ORIGINS(&res, sizeof(res));
996   ASSERT_INIT_ORIGINS(&last_fd, sizeof(last_fd), fd_o);
997   ASSERT_INIT_ORIGINS(&last_buf[3], sizeof(last_buf[3]), b_buf3_o);
998 
999   // Origins are assigned for every 4 contiguous 4-aligned bytes. After
1000   // appending src to dst, origins of src can overwrite origins of dst if their
1001   // application adddresses are within an aligned range. Other origins are not
1002   // changed.
1003   for (int i = 0; i < b_buf_len; ++i) {
1004     size_t i_addr = size_t(&last_buf[i]);
1005     if (((size_t(&last_buf[3]) & ~3UL) > i_addr) ||
1006         (((size_t(&last_buf[3]) + 4) & ~3UL) <= i_addr))
1007       ASSERT_ORIGIN(last_buf[i], b_buf_o[i]);
1008   }
1009 
1010   ASSERT_INIT_ORIGINS(&last_count, sizeof(last_count), b_buf_len_o);
1011 
1012   dfsan_set_write_callback(NULL);
1013 }
1014 
1015 void test_fgets() {
1016   char *buf = (char*) malloc(128);
1017   FILE *f = fopen("/etc/passwd", "r");
1018   dfsan_set_label(j_label, buf, 1);
1019   DEFINE_AND_SAVE_N_ORIGINS(buf, 128)
1020 
1021   char *ret = fgets(buf, sizeof(buf), f);
1022   assert(ret == buf);
1023   ASSERT_ZERO_LABEL(ret);
1024   ASSERT_EQ_ORIGIN(ret, buf);
1025   ASSERT_READ_ZERO_LABEL(buf, 128);
1026   ASSERT_SAVED_N_ORIGINS(buf, 128)
1027 
1028   dfsan_set_label(j_label, &buf, sizeof(&buf));
1029   ret = fgets(buf, sizeof(buf), f);
1030   ASSERT_LABEL(ret, j_label);
1031   ASSERT_EQ_ORIGIN(ret, buf);
1032   ASSERT_SAVED_N_ORIGINS(buf, 128)
1033 
1034   fclose(f);
1035   free(buf);
1036 }
1037 
1038 void test_getcwd() {
1039   char buf[1024];
1040   char *ptr = buf;
1041   dfsan_set_label(i_label, buf + 2, 2);
1042   DEFINE_AND_SAVE_ORIGINS(buf)
1043 
1044   char* ret = getcwd(buf, sizeof(buf));
1045   assert(ret == buf);
1046   assert(ret[0] == '/');
1047   ASSERT_ZERO_LABEL(ret);
1048   ASSERT_EQ_ORIGIN(ret, buf);
1049   ASSERT_READ_ZERO_LABEL(buf + 2, 2);
1050   ASSERT_SAVED_ORIGINS(buf)
1051 
1052   dfsan_set_label(i_label, &ptr, sizeof(ptr));
1053   ret = getcwd(ptr, sizeof(buf));
1054   ASSERT_LABEL(ret, i_label);
1055   ASSERT_EQ_ORIGIN(ret, ptr);
1056   ASSERT_SAVED_ORIGINS(buf)
1057 }
1058 
1059 void test_get_current_dir_name() {
1060   char* ret = get_current_dir_name();
1061   assert(ret);
1062   assert(ret[0] == '/');
1063   ASSERT_READ_ZERO_LABEL(ret, strlen(ret) + 1);
1064   ASSERT_ZERO_LABEL(ret);
1065 }
1066 
1067 void test_getentropy() {
1068   char buf[64];
1069   dfsan_set_label(i_label, buf + 2, 2);
1070   DEFINE_AND_SAVE_ORIGINS(buf)
1071 #if __GLIBC_PREREQ(2, 25)
1072   // glibc >= 2.25 has getentropy()
1073   int ret = getentropy(buf, sizeof(buf));
1074   ASSERT_ZERO_LABEL(ret);
1075   if (ret == 0) {
1076     ASSERT_READ_ZERO_LABEL(buf + 2, 2);
1077     ASSERT_SAVED_ORIGINS(buf)
1078   }
1079 #endif
1080 }
1081 
1082 void test_gethostname() {
1083   char buf[1024];
1084   dfsan_set_label(i_label, buf + 2, 2);
1085   DEFINE_AND_SAVE_ORIGINS(buf)
1086   int ret = gethostname(buf, sizeof(buf));
1087   assert(ret == 0);
1088   ASSERT_ZERO_LABEL(ret);
1089   ASSERT_READ_ZERO_LABEL(buf + 2, 2);
1090   ASSERT_SAVED_ORIGINS(buf)
1091 }
1092 
1093 void test_getrlimit() {
1094   struct rlimit rlim;
1095   dfsan_set_label(i_label, &rlim, sizeof(rlim));
1096   DEFINE_AND_SAVE_ORIGINS(rlim);
1097   int ret = getrlimit(RLIMIT_CPU, &rlim);
1098   assert(ret == 0);
1099   ASSERT_ZERO_LABEL(ret);
1100   ASSERT_READ_ZERO_LABEL(&rlim, sizeof(rlim));
1101   ASSERT_SAVED_ORIGINS(rlim)
1102 }
1103 
1104 void test_getrusage() {
1105   struct rusage usage;
1106   dfsan_set_label(i_label, &usage, sizeof(usage));
1107   DEFINE_AND_SAVE_ORIGINS(usage);
1108   int ret = getrusage(RUSAGE_SELF, &usage);
1109   assert(ret == 0);
1110   ASSERT_ZERO_LABEL(ret);
1111   ASSERT_READ_ZERO_LABEL(&usage, sizeof(usage));
1112   ASSERT_SAVED_ORIGINS(usage)
1113 }
1114 
1115 void test_strcpy() {
1116   char src[] = "hello world";
1117   char dst[sizeof(src) + 2];
1118   char *p_dst = dst;
1119   dfsan_set_label(0, src, sizeof(src));
1120   dfsan_set_label(0, dst, sizeof(dst));
1121   dfsan_set_label(k_label, &p_dst, sizeof(p_dst));
1122   dfsan_set_label(i_label, src + 2, 1);
1123   dfsan_set_label(j_label, src + 3, 1);
1124   dfsan_set_label(j_label, dst + 4, 1);
1125   dfsan_set_label(i_label, dst + 12, 1);
1126   char *ret = strcpy(p_dst, src);
1127   assert(ret == dst);
1128   assert(strcmp(src, dst) == 0);
1129   ASSERT_LABEL(ret, k_label);
1130   ASSERT_EQ_ORIGIN(ret, p_dst);
1131   for (int i = 0; i < strlen(src) + 1; ++i) {
1132     assert(dfsan_get_label(dst[i]) == dfsan_get_label(src[i]));
1133     if (dfsan_get_label(dst[i]))
1134       assert(dfsan_get_init_origin(&dst[i]) == dfsan_get_origin(src[i]));
1135   }
1136   // Note: if strlen(src) + 1 were used instead to compute the first untouched
1137   // byte of dest, the label would be I|J. This is because strlen() might
1138   // return a non-zero label, and because by default pointer labels are not
1139   // ignored on loads.
1140   ASSERT_LABEL(dst[12], i_label);
1141 }
1142 
1143 void test_strtol() {
1144   char non_number_buf[] = "ab ";
1145   char *endptr = NULL;
1146   long int ret = strtol(non_number_buf, &endptr, 10);
1147   assert(ret == 0);
1148   assert(endptr == non_number_buf);
1149   ASSERT_ZERO_LABEL(ret);
1150 
1151   char buf[] = "1234578910";
1152   int base = 10;
1153   dfsan_set_label(k_label, &base, sizeof(base));
1154   ret = strtol(buf, &endptr, base);
1155   assert(ret == 1234578910);
1156   assert(endptr == buf + 10);
1157   ASSERT_LABEL(ret, k_label);
1158   ASSERT_EQ_ORIGIN(ret, base);
1159 
1160   dfsan_set_label(i_label, buf + 1, 1);
1161   dfsan_set_label(j_label, buf + 10, 1);
1162   ret = strtol(buf, &endptr, 10);
1163   assert(ret == 1234578910);
1164   assert(endptr == buf + 10);
1165   ASSERT_LABEL(ret, i_j_label);
1166   ASSERT_EQ_ORIGIN(ret, buf[1]);
1167 }
1168 
1169 void test_strtoll() {
1170   char non_number_buf[] = "ab ";
1171   char *endptr = NULL;
1172   long long int ret = strtoll(non_number_buf, &endptr, 10);
1173   assert(ret == 0);
1174   assert(endptr == non_number_buf);
1175   ASSERT_ZERO_LABEL(ret);
1176 
1177   char buf[] = "1234578910 ";
1178   int base = 10;
1179   dfsan_set_label(k_label, &base, sizeof(base));
1180   ret = strtoll(buf, &endptr, base);
1181   assert(ret == 1234578910);
1182   assert(endptr == buf + 10);
1183   ASSERT_LABEL(ret, k_label);
1184   ASSERT_EQ_ORIGIN(ret, base);
1185 
1186   dfsan_set_label(i_label, buf + 1, 1);
1187   dfsan_set_label(j_label, buf + 2, 1);
1188   ret = strtoll(buf, &endptr, 10);
1189   assert(ret == 1234578910);
1190   assert(endptr == buf + 10);
1191   ASSERT_LABEL(ret, i_j_label);
1192   ASSERT_EQ_ORIGIN(ret, buf[1]);
1193 }
1194 
1195 void test_strtoul() {
1196   char non_number_buf[] = "xy ";
1197   char *endptr = NULL;
1198   long unsigned int ret = strtoul(non_number_buf, &endptr, 16);
1199   assert(ret == 0);
1200   assert(endptr == non_number_buf);
1201   ASSERT_ZERO_LABEL(ret);
1202 
1203   char buf[] = "ffffffffffffaa";
1204   int base = 16;
1205   dfsan_set_label(k_label, &base, sizeof(base));
1206   ret = strtoul(buf, &endptr, base);
1207   assert(ret == 72057594037927850);
1208   assert(endptr == buf + 14);
1209   ASSERT_LABEL(ret, k_label);
1210   ASSERT_EQ_ORIGIN(ret, base);
1211 
1212   dfsan_set_label(i_label, buf + 1, 1);
1213   dfsan_set_label(j_label, buf + 2, 1);
1214   ret = strtoul(buf, &endptr, 16);
1215   assert(ret == 72057594037927850);
1216   assert(endptr == buf + 14);
1217   ASSERT_LABEL(ret, i_j_label);
1218   ASSERT_EQ_ORIGIN(ret, buf[1]);
1219 }
1220 
1221 void test_strtoull() {
1222   char non_number_buf[] = "xy ";
1223   char *endptr = NULL;
1224   long long unsigned int ret = strtoull(non_number_buf, &endptr, 16);
1225   assert(ret == 0);
1226   assert(endptr == non_number_buf);
1227   ASSERT_ZERO_LABEL(ret);
1228 
1229   char buf[] = "ffffffffffffffaa";
1230   int base = 16;
1231   dfsan_set_label(k_label, &base, sizeof(base));
1232   ret = strtoull(buf, &endptr, base);
1233   assert(ret == 0xffffffffffffffaa);
1234   assert(endptr == buf + 16);
1235   ASSERT_LABEL(ret, k_label);
1236   ASSERT_EQ_ORIGIN(ret, base);
1237 
1238   dfsan_set_label(i_label, buf + 1, 1);
1239   dfsan_set_label(j_label, buf + 2, 1);
1240   ret = strtoull(buf, &endptr, 16);
1241   assert(ret == 0xffffffffffffffaa);
1242   assert(endptr == buf + 16);
1243   ASSERT_LABEL(ret, i_j_label);
1244   ASSERT_EQ_ORIGIN(ret, buf[1]);
1245 }
1246 
1247 void test_strtod() {
1248   char non_number_buf[] = "ab ";
1249   char *endptr = NULL;
1250   double ret = strtod(non_number_buf, &endptr);
1251   assert(ret == 0);
1252   assert(endptr == non_number_buf);
1253   ASSERT_ZERO_LABEL(ret);
1254 
1255   char buf[] = "12345.76 foo";
1256   dfsan_set_label(i_label, buf + 1, 1);
1257   dfsan_set_label(j_label, buf + 6, 1);
1258   ret = strtod(buf, &endptr);
1259   assert(ret == 12345.76);
1260   assert(endptr == buf + 8);
1261   ASSERT_LABEL(ret, i_j_label);
1262   ASSERT_EQ_ORIGIN(ret, buf[1]);
1263 }
1264 
1265 void test_time() {
1266   time_t t = 0;
1267   dfsan_set_label(i_label, &t, 1);
1268   DEFINE_AND_SAVE_ORIGINS(t)
1269   time_t ret = time(&t);
1270   assert(ret == t);
1271   assert(ret > 0);
1272   ASSERT_ZERO_LABEL(ret);
1273   ASSERT_ZERO_LABEL(t);
1274   ASSERT_SAVED_ORIGINS(t)
1275 }
1276 
1277 void test_inet_pton() {
1278   char addr4[] = "127.0.0.1";
1279   dfsan_set_label(i_label, addr4 + 3, 1);
1280   struct in_addr in4;
1281   int ret4 = inet_pton(AF_INET, addr4, &in4);
1282   assert(ret4 == 1);
1283   ASSERT_ZERO_LABEL(ret4);
1284   ASSERT_READ_LABEL(&in4, sizeof(in4), i_label);
1285   ASSERT_ORIGINS(&in4, sizeof(in4), dfsan_get_origin((long)(addr4[3])))
1286   assert(in4.s_addr == htonl(0x7f000001));
1287 
1288   char addr6[] = "::1";
1289   dfsan_set_label(j_label, addr6 + 3, 1);
1290   struct in6_addr in6;
1291   int ret6 = inet_pton(AF_INET6, addr6, &in6);
1292   assert(ret6 == 1);
1293   ASSERT_ZERO_LABEL(ret6);
1294   ASSERT_READ_LABEL(((char *) &in6) + sizeof(in6) - 1, 1, j_label);
1295   ASSERT_ORIGINS(&in6, sizeof(in6), dfsan_get_origin((long)(addr6[3])))
1296 }
1297 
1298 void test_localtime_r() {
1299   time_t t0 = 1384800998;
1300   struct tm t1;
1301   dfsan_set_label(i_label, &t0, sizeof(t0));
1302   dfsan_origin t0_o = dfsan_get_origin((long)t0);
1303   struct tm *pt1 = &t1;
1304   dfsan_set_label(j_label, &pt1, sizeof(pt1));
1305   dfsan_origin pt1_o = dfsan_get_origin((long)pt1);
1306 
1307 #ifndef ORIGIN_TRACKING
1308   (void)t0_o;
1309   (void)pt1_o;
1310 #endif
1311 
1312   struct tm *ret = localtime_r(&t0, pt1);
1313   assert(ret == &t1);
1314   assert(t1.tm_min == 56);
1315   ASSERT_LABEL(ret, j_label);
1316   ASSERT_INIT_ORIGIN(&ret, pt1_o);
1317   ASSERT_READ_LABEL(&ret, sizeof(ret), j_label);
1318   ASSERT_LABEL(t1.tm_mon, i_label);
1319   ASSERT_ORIGIN(t1.tm_mon, t0_o);
1320 }
1321 
1322 void test_getpwuid_r() {
1323   struct passwd pwd;
1324   char buf[1024];
1325   struct passwd *result;
1326 
1327   dfsan_set_label(i_label, &pwd, 4);
1328   DEFINE_AND_SAVE_ORIGINS(pwd)
1329   DEFINE_AND_SAVE_ORIGINS(buf)
1330   int ret = getpwuid_r(0, &pwd, buf, sizeof(buf), &result);
1331   assert(ret == 0);
1332   assert(strcmp(pwd.pw_name, "root") == 0);
1333   assert(result == &pwd);
1334   ASSERT_ZERO_LABEL(ret);
1335   ASSERT_READ_ZERO_LABEL(&pwd, 4);
1336   ASSERT_SAVED_ORIGINS(pwd)
1337   ASSERT_SAVED_ORIGINS(buf)
1338 }
1339 
1340 void test_epoll_wait() {
1341   // Set up a pipe to monitor with epoll.
1342   int pipe_fds[2];
1343   int ret = pipe(pipe_fds);
1344   assert(ret != -1);
1345 
1346   // Configure epoll to monitor the pipe.
1347   int epfd = epoll_create1(0);
1348   assert(epfd != -1);
1349   struct epoll_event event;
1350   event.events = EPOLLIN;
1351   event.data.fd = pipe_fds[0];
1352   ret = epoll_ctl(epfd, EPOLL_CTL_ADD, pipe_fds[0], &event);
1353   assert(ret != -1);
1354 
1355   // Test epoll_wait when no events have occurred.
1356   event = {};
1357   dfsan_set_label(i_label, &event, sizeof(event));
1358   DEFINE_AND_SAVE_ORIGINS(event)
1359   ret = epoll_wait(epfd, &event, /*maxevents=*/1, /*timeout=*/0);
1360   assert(ret == 0);
1361   assert(event.events == 0);
1362   assert(event.data.fd == 0);
1363   ASSERT_ZERO_LABEL(ret);
1364   ASSERT_READ_LABEL(&event, sizeof(event), i_label);
1365   ASSERT_SAVED_ORIGINS(event)
1366 
1367   // Test epoll_wait when an event occurs.
1368   write(pipe_fds[1], "x", 1);
1369   ret = epoll_wait(epfd, &event, /*maxevents=*/1, /*timeout=*/0);
1370   assert(ret == 1);
1371   assert(event.events == EPOLLIN);
1372   assert(event.data.fd == pipe_fds[0]);
1373   ASSERT_ZERO_LABEL(ret);
1374   ASSERT_READ_ZERO_LABEL(&event, sizeof(event));
1375   ASSERT_SAVED_ORIGINS(event)
1376 
1377   // Clean up.
1378   close(epfd);
1379   close(pipe_fds[0]);
1380   close(pipe_fds[1]);
1381 }
1382 
1383 void test_poll() {
1384   struct pollfd fd;
1385   fd.fd = 0;
1386   fd.events = POLLIN;
1387   dfsan_set_label(i_label, &fd.revents, sizeof(fd.revents));
1388   DEFINE_AND_SAVE_ORIGINS(fd)
1389   int ret = poll(&fd, 1, 1);
1390   ASSERT_ZERO_LABEL(ret);
1391   ASSERT_ZERO_LABEL(fd.revents);
1392   ASSERT_SAVED_ORIGINS(fd)
1393   assert(ret >= 0);
1394 }
1395 
1396 void test_select() {
1397   struct timeval t;
1398   fd_set fds;
1399   t.tv_sec = 2;
1400   FD_SET(0, &fds);
1401   dfsan_set_label(i_label, &fds, sizeof(fds));
1402   dfsan_set_label(j_label, &t, sizeof(t));
1403   DEFINE_AND_SAVE_ORIGINS(fds)
1404   DEFINE_AND_SAVE_ORIGINS(t)
1405   int ret = select(1, &fds, NULL, NULL, &t);
1406   assert(ret >= 0);
1407   ASSERT_ZERO_LABEL(ret);
1408   ASSERT_ZERO_LABEL(t.tv_sec);
1409   ASSERT_READ_ZERO_LABEL(&fds, sizeof(fds));
1410   ASSERT_SAVED_ORIGINS(fds)
1411   ASSERT_SAVED_ORIGINS(t)
1412 }
1413 
1414 void test_sched_getaffinity() {
1415   cpu_set_t mask;
1416   dfsan_set_label(j_label, &mask, 1);
1417   DEFINE_AND_SAVE_ORIGINS(mask)
1418   int ret = sched_getaffinity(0, sizeof(mask), &mask);
1419   assert(ret == 0);
1420   ASSERT_ZERO_LABEL(ret);
1421   ASSERT_READ_ZERO_LABEL(&mask, sizeof(mask));
1422   ASSERT_SAVED_ORIGINS(mask)
1423 }
1424 
1425 void test_sigemptyset() {
1426   sigset_t set;
1427   dfsan_set_label(j_label, &set, 1);
1428   DEFINE_AND_SAVE_ORIGINS(set)
1429   int ret = sigemptyset(&set);
1430   assert(ret == 0);
1431   ASSERT_ZERO_LABEL(ret);
1432   ASSERT_READ_ZERO_LABEL(&set, sizeof(set));
1433   ASSERT_SAVED_ORIGINS(set)
1434 }
1435 
1436 static void SignalHandler(int signo) {}
1437 
1438 static void SignalAction(int signo, siginfo_t *si, void *uc) {}
1439 
1440 void test_sigaction() {
1441   struct sigaction newact_with_sigaction = {};
1442   newact_with_sigaction.sa_flags = SA_SIGINFO;
1443   newact_with_sigaction.sa_sigaction = SignalAction;
1444 
1445   // Set sigaction to be SignalAction, save the last one into origin_act
1446   struct sigaction origin_act;
1447   dfsan_set_label(j_label, &origin_act, 1);
1448   DEFINE_AND_SAVE_ORIGINS(origin_act)
1449   int ret = sigaction(SIGUSR1, &newact_with_sigaction, &origin_act);
1450   assert(ret == 0);
1451   ASSERT_ZERO_LABEL(ret);
1452   ASSERT_READ_ZERO_LABEL(&origin_act, sizeof(origin_act));
1453   ASSERT_SAVED_ORIGINS(origin_act)
1454 
1455   struct sigaction newact_with_sighandler = {};
1456   newact_with_sighandler.sa_handler = SignalHandler;
1457 
1458   // Set sigaction to be SignalHandler, check the last one is SignalAction
1459   struct sigaction oldact;
1460   assert(0 == sigaction(SIGUSR1, &newact_with_sighandler, &oldact));
1461   assert(oldact.sa_sigaction == SignalAction);
1462   assert(oldact.sa_flags & SA_SIGINFO);
1463 
1464   // Set SIG_IGN or SIG_DFL, and check the previous one is expected.
1465   newact_with_sighandler.sa_handler = SIG_IGN;
1466   assert(0 == sigaction(SIGUSR1, &newact_with_sighandler, &oldact));
1467   assert(oldact.sa_handler == SignalHandler);
1468   assert((oldact.sa_flags & SA_SIGINFO) == 0);
1469 
1470   newact_with_sighandler.sa_handler = SIG_DFL;
1471   assert(0 == sigaction(SIGUSR1, &newact_with_sighandler, &oldact));
1472   assert(oldact.sa_handler == SIG_IGN);
1473   assert((oldact.sa_flags & SA_SIGINFO) == 0);
1474 
1475   // Restore sigaction to the orginal setting, check the last one is SignalHandler
1476   assert(0 == sigaction(SIGUSR1, &origin_act, &oldact));
1477   assert(oldact.sa_handler == SIG_DFL);
1478   assert((oldact.sa_flags & SA_SIGINFO) == 0);
1479 }
1480 
1481 void test_signal() {
1482   // Set signal to be SignalHandler, save the previous one into
1483   // old_signal_handler.
1484   sighandler_t old_signal_handler = signal(SIGHUP, SignalHandler);
1485   ASSERT_ZERO_LABEL(old_signal_handler);
1486 
1487   // Set SIG_IGN or SIG_DFL, and check the previous one is expected.
1488   assert(SignalHandler == signal(SIGHUP, SIG_DFL));
1489   assert(SIG_DFL == signal(SIGHUP, SIG_IGN));
1490 
1491   // Restore signal to old_signal_handler.
1492   assert(SIG_IGN == signal(SIGHUP, old_signal_handler));
1493 }
1494 
1495 void test_sigaltstack() {
1496   stack_t old_altstack = {};
1497   dfsan_set_label(j_label, &old_altstack, sizeof(old_altstack));
1498   DEFINE_AND_SAVE_ORIGINS(old_altstack)
1499   int ret = sigaltstack(NULL, &old_altstack);
1500   assert(ret == 0);
1501   ASSERT_ZERO_LABEL(ret);
1502   ASSERT_READ_ZERO_LABEL(&old_altstack, sizeof(old_altstack));
1503   ASSERT_SAVED_ORIGINS(old_altstack)
1504 }
1505 
1506 void test_gettimeofday() {
1507   struct timeval tv;
1508   struct timezone tz;
1509   dfsan_set_label(i_label, &tv, sizeof(tv));
1510   dfsan_set_label(j_label, &tz, sizeof(tz));
1511   DEFINE_AND_SAVE_ORIGINS(tv)
1512   DEFINE_AND_SAVE_ORIGINS(tz)
1513   int ret = gettimeofday(&tv, &tz);
1514   assert(ret == 0);
1515   ASSERT_READ_ZERO_LABEL(&tv, sizeof(tv));
1516   ASSERT_READ_ZERO_LABEL(&tz, sizeof(tz));
1517   ASSERT_SAVED_ORIGINS(tv)
1518   ASSERT_SAVED_ORIGINS(tz)
1519 }
1520 
1521 void *pthread_create_test_cb(void *p) {
1522   assert(p == (void *)1);
1523   ASSERT_ZERO_LABEL(p);
1524   return (void *)2;
1525 }
1526 
1527 void test_pthread_create() {
1528   pthread_t pt;
1529   int create_ret = pthread_create(&pt, 0, pthread_create_test_cb, (void *)1);
1530   assert(create_ret == 0);
1531   ASSERT_ZERO_LABEL(create_ret);
1532   void *cbrv;
1533   dfsan_set_label(i_label, &cbrv, sizeof(cbrv));
1534   DEFINE_AND_SAVE_ORIGINS(cbrv)
1535   int joint_ret = pthread_join(pt, &cbrv);
1536   assert(joint_ret == 0);
1537   assert(cbrv == (void *)2);
1538   ASSERT_ZERO_LABEL(joint_ret);
1539   ASSERT_ZERO_LABEL(cbrv);
1540   ASSERT_SAVED_ORIGINS(cbrv);
1541 }
1542 
1543 // Tested by test_pthread_create().  This empty function is here to appease the
1544 // check-wrappers script.
1545 void test_pthread_join() {}
1546 
1547 int dl_iterate_phdr_test_cb(struct dl_phdr_info *info, size_t size,
1548                             void *data) {
1549   assert(data == (void *)3);
1550   ASSERT_ZERO_LABEL(info);
1551   ASSERT_ZERO_LABEL(size);
1552   ASSERT_ZERO_LABEL(data);
1553   return 0;
1554 }
1555 
1556 void test_dl_iterate_phdr() {
1557   dl_iterate_phdr(dl_iterate_phdr_test_cb, (void *)3);
1558 }
1559 
1560 // On glibc < 2.27, this symbol is not available.  Mark it weak so we can skip
1561 // testing in this case.
1562 __attribute__((weak)) extern "C" void _dl_get_tls_static_info(size_t *sizep,
1563                                                               size_t *alignp);
1564 
1565 void test__dl_get_tls_static_info() {
1566   if (!_dl_get_tls_static_info)
1567     return;
1568   size_t sizep = 0, alignp = 0;
1569   dfsan_set_label(i_label, &sizep, sizeof(sizep));
1570   dfsan_set_label(i_label, &alignp, sizeof(alignp));
1571   dfsan_origin sizep_o = dfsan_get_origin(sizep);
1572   dfsan_origin alignp_o = dfsan_get_origin(alignp);
1573 #ifndef ORIGIN_TRACKING
1574   (void)sizep_o;
1575   (void)alignp_o;
1576 #endif
1577   _dl_get_tls_static_info(&sizep, &alignp);
1578   ASSERT_ZERO_LABEL(sizep);
1579   ASSERT_ZERO_LABEL(alignp);
1580   ASSERT_ORIGIN(sizep, sizep_o);
1581   ASSERT_ORIGIN(alignp, alignp_o);
1582 }
1583 
1584 void test_strrchr() {
1585   char str1[] = "str1str1";
1586 
1587   char *p = str1;
1588   dfsan_set_label(j_label, &p, sizeof(p));
1589 
1590   char *rv = strrchr(p, 'r');
1591   assert(rv == &str1[6]);
1592   ASSERT_LABEL(rv, j_label);
1593   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p);
1594 
1595   char c = 'r';
1596   dfsan_set_label(k_label, &c, sizeof(c));
1597   rv = strrchr(str1, c);
1598   assert(rv == &str1[6]);
1599 #ifdef STRICT_DATA_DEPENDENCIES
1600   ASSERT_ZERO_LABEL(rv);
1601 #else
1602   ASSERT_LABEL(rv, k_label);
1603   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, c);
1604 #endif
1605 
1606   dfsan_set_label(i_label, &str1[7], 1);
1607 
1608   rv = strrchr(str1, 'r');
1609   assert(rv == &str1[6]);
1610 #ifdef STRICT_DATA_DEPENDENCIES
1611   ASSERT_ZERO_LABEL(rv);
1612 #else
1613   ASSERT_LABEL(rv, i_label);
1614   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, str1[7]);
1615 #endif
1616 }
1617 
1618 void test_strstr() {
1619   char str1[] = "str1str1";
1620 
1621   char *p1 = str1;
1622   dfsan_set_label(k_label, &p1, sizeof(p1));
1623   char *rv = strstr(p1, "1s");
1624   assert(rv == &str1[3]);
1625   ASSERT_LABEL(rv, k_label);
1626   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p1);
1627 
1628   char str2[] = "1s";
1629   char *p2 = str2;
1630   dfsan_set_label(m_label, &p2, sizeof(p2));
1631   rv = strstr(str1, p2);
1632   assert(rv == &str1[3]);
1633 #ifdef STRICT_DATA_DEPENDENCIES
1634   ASSERT_ZERO_LABEL(rv);
1635 #else
1636   ASSERT_LABEL(rv, m_label);
1637   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p2);
1638 #endif
1639 
1640   dfsan_set_label(n_label, &str2[0], 1);
1641   rv = strstr(str1, str2);
1642   assert(rv == &str1[3]);
1643 #ifdef STRICT_DATA_DEPENDENCIES
1644   ASSERT_ZERO_LABEL(rv);
1645 #else
1646   ASSERT_LABEL(rv, n_label);
1647   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, str2[0]);
1648 #endif
1649 
1650   dfsan_set_label(i_label, &str1[3], 1);
1651   dfsan_set_label(j_label, &str1[5], 1);
1652 
1653   rv = strstr(str1, "1s");
1654   assert(rv == &str1[3]);
1655 #ifdef STRICT_DATA_DEPENDENCIES
1656   ASSERT_ZERO_LABEL(rv);
1657 #else
1658   ASSERT_LABEL(rv, i_label);
1659   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, str1[3]);
1660 #endif
1661 
1662   rv = strstr(str1, "2s");
1663   assert(rv == NULL);
1664 #ifdef STRICT_DATA_DEPENDENCIES
1665   ASSERT_ZERO_LABEL(rv);
1666 #else
1667   ASSERT_LABEL(rv, i_j_label);
1668   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, str1[3]);
1669 #endif
1670 }
1671 
1672 void test_strpbrk() {
1673   char s[] = "abcdefg";
1674   char accept[] = "123fd";
1675 
1676   char *p_s = s;
1677   char *p_accept = accept;
1678 
1679   dfsan_set_label(n_label, &p_accept, sizeof(p_accept));
1680 
1681   char *rv = strpbrk(p_s, p_accept);
1682   assert(rv == &s[3]);
1683 #ifdef STRICT_DATA_DEPENDENCIES
1684   ASSERT_ZERO_LABEL(rv);
1685 #else
1686   ASSERT_LABEL(rv, n_label);
1687   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p_accept);
1688 #endif
1689 
1690   dfsan_set_label(m_label, &p_s, sizeof(p_s));
1691 
1692   rv = strpbrk(p_s, p_accept);
1693   assert(rv == &s[3]);
1694 #ifdef STRICT_DATA_DEPENDENCIES
1695   ASSERT_LABEL(rv, m_label);
1696   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p_s);
1697 #else
1698   ASSERT_LABEL(rv, dfsan_union(m_label, n_label));
1699   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p_s);
1700 #endif
1701 
1702   dfsan_set_label(i_label, &s[5], 1);
1703   dfsan_set_label(j_label, &accept[1], 1);
1704 
1705   rv = strpbrk(s, accept);
1706   assert(rv == &s[3]);
1707 #ifdef STRICT_DATA_DEPENDENCIES
1708   ASSERT_ZERO_LABEL(rv);
1709 #else
1710   ASSERT_LABEL(rv, j_label);
1711   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, accept[1]);
1712 #endif
1713 
1714   char *ps = s;
1715   dfsan_set_label(j_label, &ps, sizeof(ps));
1716 
1717   rv = strpbrk(ps, "123gf");
1718   assert(rv == &s[5]);
1719 #ifdef STRICT_DATA_DEPENDENCIES
1720   ASSERT_LABEL(rv, j_label);
1721 #else
1722   ASSERT_LABEL(rv, i_j_label);
1723   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, s[5]);
1724 #endif
1725 
1726   rv = strpbrk(ps, "123");
1727   assert(rv == NULL);
1728 #ifdef STRICT_DATA_DEPENDENCIES
1729   ASSERT_ZERO_LABEL(rv);
1730 #else
1731   ASSERT_LABEL(rv, i_j_label);
1732   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, s[5]);
1733 #endif
1734 }
1735 
1736 void test_strsep() {
1737   char *s = strdup("Hello world/");
1738   char *delim = strdup(" /");
1739 
1740   char *p_s = s;
1741   char *base = s;
1742   char *p_delim = delim;
1743 
1744   // taint delim bytes
1745   dfsan_set_label(i_label, p_delim, strlen(p_delim));
1746   // taint delim pointer
1747   dfsan_set_label(j_label, &p_delim, sizeof(p_delim));
1748   // taint the string data bytes
1749   dfsan_set_label(k_label, s, 5);
1750   // taint the string pointer
1751   dfsan_set_label(m_label, &p_s, sizeof(p_s));
1752 
1753   char *rv = strsep(&p_s, p_delim);
1754   assert(rv == &base[0]);
1755 #ifdef STRICT_DATA_DEPENDENCIES
1756   ASSERT_LABEL(rv, m_label);
1757   ASSERT_READ_LABEL(rv, strlen(rv), k_label);
1758 #else
1759   ASSERT_LABEL(rv, dfsan_union(dfsan_union(i_label, j_label),
1760                                dfsan_union(k_label, m_label)));
1761   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, p_s);
1762 #endif
1763 
1764   // taint the remaining string's pointer
1765   char **pp_s = &p_s;
1766   char **pp_s_base = pp_s;
1767   dfsan_set_label(n_label, pp_s, sizeof(pp_s));
1768 
1769   rv = strsep(pp_s, p_delim);
1770 
1771   assert(rv == &base[6]);
1772 #ifdef STRICT_DATA_DEPENDENCIES
1773   ASSERT_LABEL(rv, n_label);
1774   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, *pp_s);
1775 #else
1776   ASSERT_LABEL(rv, dfsan_union(dfsan_union(i_label, j_label), n_label));
1777   ASSERT_INIT_ORIGIN_EQ_ORIGIN(&rv, *pp_s);
1778 #endif
1779 }
1780 
1781 void test_memchr() {
1782   char str1[] = "str1";
1783   dfsan_set_label(i_label, &str1[3], 1);
1784   dfsan_set_label(j_label, &str1[4], 1);
1785 
1786   char *crv = (char *) memchr(str1, 'r', sizeof(str1));
1787   assert(crv == &str1[2]);
1788   ASSERT_ZERO_LABEL(crv);
1789 
1790   char c = 'r';
1791   dfsan_set_label(k_label, &c, sizeof(c));
1792   crv = (char *)memchr(str1, c, sizeof(str1));
1793   assert(crv == &str1[2]);
1794 #ifdef STRICT_DATA_DEPENDENCIES
1795   ASSERT_ZERO_LABEL(crv);
1796 #else
1797   ASSERT_LABEL(crv, k_label);
1798   ASSERT_EQ_ORIGIN(crv, c);
1799 #endif
1800 
1801   char *ptr = str1;
1802   dfsan_set_label(k_label, &ptr, sizeof(ptr));
1803   crv = (char *)memchr(ptr, 'r', sizeof(str1));
1804   assert(crv == &str1[2]);
1805   ASSERT_LABEL(crv, k_label);
1806   ASSERT_EQ_ORIGIN(crv, ptr);
1807 
1808   crv = (char *) memchr(str1, '1', sizeof(str1));
1809   assert(crv == &str1[3]);
1810 #ifdef STRICT_DATA_DEPENDENCIES
1811   ASSERT_ZERO_LABEL(crv);
1812 #else
1813   ASSERT_LABEL(crv, i_label);
1814   ASSERT_EQ_ORIGIN(crv, str1[3]);
1815 #endif
1816 
1817   crv = (char *) memchr(str1, 'x', sizeof(str1));
1818   assert(!crv);
1819 #ifdef STRICT_DATA_DEPENDENCIES
1820   ASSERT_ZERO_LABEL(crv);
1821 #else
1822   ASSERT_LABEL(crv, i_j_label);
1823   ASSERT_EQ_ORIGIN(crv, str1[3]);
1824 #endif
1825 }
1826 
1827 void alarm_handler(int unused) {
1828   ;
1829 }
1830 
1831 void test_nanosleep() {
1832   struct timespec req, rem;
1833   req.tv_sec = 1;
1834   req.tv_nsec = 0;
1835   dfsan_set_label(i_label, &rem, sizeof(rem));
1836   DEFINE_AND_SAVE_ORIGINS(rem)
1837 
1838   // non interrupted
1839   int rv = nanosleep(&req, &rem);
1840   assert(rv == 0);
1841   ASSERT_ZERO_LABEL(rv);
1842   ASSERT_READ_LABEL(&rem, 1, i_label);
1843   ASSERT_SAVED_ORIGINS(rem)
1844 
1845   // interrupted by an alarm
1846   signal(SIGALRM, alarm_handler);
1847   req.tv_sec = 3;
1848   alarm(1);
1849   rv = nanosleep(&req, &rem);
1850   assert(rv == -1);
1851   ASSERT_ZERO_LABEL(rv);
1852   ASSERT_READ_ZERO_LABEL(&rem, sizeof(rem));
1853   ASSERT_SAVED_ORIGINS(rem)
1854 }
1855 
1856 void test_socketpair() {
1857   int fd[2];
1858   dfsan_origin fd_o[2];
1859 
1860   dfsan_set_label(i_label, fd, sizeof(fd));
1861   fd_o[0] = dfsan_get_origin((long)(fd[0]));
1862   fd_o[1] = dfsan_get_origin((long)(fd[1]));
1863   int rv = socketpair(PF_LOCAL, SOCK_STREAM, 0, fd);
1864   assert(rv == 0);
1865   ASSERT_ZERO_LABEL(rv);
1866   ASSERT_READ_ZERO_LABEL(fd, sizeof(fd));
1867   ASSERT_ORIGIN(fd[0], fd_o[0]);
1868   ASSERT_ORIGIN(fd[1], fd_o[1]);
1869 }
1870 
1871 void test_getpeername() {
1872   int sockfds[2];
1873   int ret = socketpair(AF_UNIX, SOCK_DGRAM, 0, sockfds);
1874   assert(ret != -1);
1875 
1876   struct sockaddr addr = {};
1877   socklen_t addrlen = sizeof(addr);
1878   dfsan_set_label(i_label, &addr, addrlen);
1879   dfsan_set_label(i_label, &addrlen, sizeof(addrlen));
1880   DEFINE_AND_SAVE_ORIGINS(addr)
1881   DEFINE_AND_SAVE_ORIGINS(addrlen)
1882 
1883   ret = getpeername(sockfds[0], &addr, &addrlen);
1884   assert(ret != -1);
1885   ASSERT_ZERO_LABEL(ret);
1886   ASSERT_ZERO_LABEL(addrlen);
1887   assert(addrlen < sizeof(addr));
1888   ASSERT_READ_ZERO_LABEL(&addr, addrlen);
1889   ASSERT_READ_LABEL(((char *)&addr) + addrlen, 1, i_label);
1890   ASSERT_SAVED_ORIGINS(addr)
1891   ASSERT_SAVED_ORIGINS(addrlen)
1892 
1893   close(sockfds[0]);
1894   close(sockfds[1]);
1895 }
1896 
1897 void test_getsockname() {
1898   int sockfd = socket(AF_UNIX, SOCK_DGRAM, 0);
1899   assert(sockfd != -1);
1900 
1901   struct sockaddr addr = {};
1902   socklen_t addrlen = sizeof(addr);
1903   dfsan_set_label(i_label, &addr, addrlen);
1904   dfsan_set_label(i_label, &addrlen, sizeof(addrlen));
1905   DEFINE_AND_SAVE_ORIGINS(addr)
1906   DEFINE_AND_SAVE_ORIGINS(addrlen)
1907   int ret = getsockname(sockfd, &addr, &addrlen);
1908   assert(ret != -1);
1909   ASSERT_ZERO_LABEL(ret);
1910   ASSERT_ZERO_LABEL(addrlen);
1911   assert(addrlen < sizeof(addr));
1912   ASSERT_READ_ZERO_LABEL(&addr, addrlen);
1913   ASSERT_READ_LABEL(((char *)&addr) + addrlen, 1, i_label);
1914   ASSERT_SAVED_ORIGINS(addr)
1915   ASSERT_SAVED_ORIGINS(addrlen)
1916 
1917   close(sockfd);
1918 }
1919 
1920 void test_getsockopt() {
1921   int sockfd = socket(AF_UNIX, SOCK_DGRAM, 0);
1922   assert(sockfd != -1);
1923 
1924   int optval[2] = {-1, -1};
1925   socklen_t optlen = sizeof(optval);
1926   dfsan_set_label(i_label, &optval, sizeof(optval));
1927   dfsan_set_label(i_label, &optlen, sizeof(optlen));
1928   DEFINE_AND_SAVE_ORIGINS(optval)
1929   DEFINE_AND_SAVE_ORIGINS(optlen)
1930   int ret = getsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE, &optval, &optlen);
1931   assert(ret != -1);
1932   assert(optlen == sizeof(int));
1933   assert(optval[0] == 0);
1934   assert(optval[1] == -1);
1935   ASSERT_ZERO_LABEL(ret);
1936   ASSERT_ZERO_LABEL(optlen);
1937   ASSERT_ZERO_LABEL(optval[0]);
1938   ASSERT_LABEL(optval[1], i_label);
1939   ASSERT_SAVED_ORIGINS(optval)
1940   ASSERT_SAVED_ORIGINS(optlen)
1941 
1942   close(sockfd);
1943 }
1944 
1945 void test_write() {
1946   int fd = open("/dev/null", O_WRONLY);
1947 
1948   char buf[] = "a string";
1949   int len = strlen(buf);
1950 
1951   // The result of a write always unlabeled.
1952   int res = write(fd, buf, len);
1953   assert(res > 0);
1954   ASSERT_ZERO_LABEL(res);
1955 
1956   // Label all arguments to write().
1957   dfsan_set_label(i_label, &(buf[3]), 1);
1958   dfsan_set_label(j_label, &fd, sizeof(fd));
1959   dfsan_set_label(k_label, &len, sizeof(len));
1960 
1961   // The value returned by write() should have no label.
1962   res = write(fd, buf, len);
1963   ASSERT_ZERO_LABEL(res);
1964 
1965   close(fd);
1966 }
1967 
1968 template <class T>
1969 void test_sprintf_chunk(const char* expected, const char* format, T arg) {
1970   char buf[512];
1971   memset(buf, 'a', sizeof(buf));
1972 
1973   char padded_expected[512];
1974   strcpy(padded_expected, "foo ");
1975   strcat(padded_expected, expected);
1976   strcat(padded_expected, " bar");
1977 
1978   char padded_format[512];
1979   strcpy(padded_format, "foo ");
1980   strcat(padded_format, format);
1981   strcat(padded_format, " bar");
1982 
1983   // Non labelled arg.
1984   assert(sprintf(buf, padded_format,  arg) == strlen(padded_expected));
1985   assert(strcmp(buf, padded_expected) == 0);
1986   ASSERT_READ_LABEL(buf, strlen(padded_expected), 0);
1987   memset(buf, 'a', sizeof(buf));
1988 
1989   // Labelled arg.
1990   dfsan_set_label(i_label, &arg, sizeof(arg));
1991   dfsan_origin a_o = dfsan_get_origin((long)(arg));
1992 #ifndef ORIGIN_TRACKING
1993   (void)a_o;
1994 #endif
1995   assert(sprintf(buf, padded_format,  arg) == strlen(padded_expected));
1996   assert(strcmp(buf, padded_expected) == 0);
1997   ASSERT_READ_LABEL(buf, 4, 0);
1998   ASSERT_READ_LABEL(buf + 4, strlen(padded_expected) - 8, i_label);
1999   ASSERT_INIT_ORIGINS(buf + 4, strlen(padded_expected) - 8, a_o);
2000   ASSERT_READ_LABEL(buf + (strlen(padded_expected) - 4), 4, 0);
2001 }
2002 
2003 void test_sprintf() {
2004   char buf[2048];
2005   memset(buf, 'a', sizeof(buf));
2006 
2007   // Test formatting (no conversion specifier).
2008   assert(sprintf(buf, "Hello world!") == 12);
2009   assert(strcmp(buf, "Hello world!") == 0);
2010   ASSERT_READ_LABEL(buf, sizeof(buf), 0);
2011 
2012   // Test for extra arguments.
2013   assert(sprintf(buf, "Hello world!", 42, "hello") == 12);
2014   assert(strcmp(buf, "Hello world!") == 0);
2015   ASSERT_READ_LABEL(buf, sizeof(buf), 0);
2016 
2017   // Test formatting & label propagation (multiple conversion specifiers): %s,
2018   // %d, %n, %f, and %%.
2019   const char* s = "world";
2020   int m = 8;
2021   int d = 27;
2022   dfsan_set_label(k_label, (void *) (s + 1), 2);
2023   dfsan_origin s_o = dfsan_get_origin((long)(s[1]));
2024   dfsan_set_label(i_label, &m, sizeof(m));
2025   dfsan_origin m_o = dfsan_get_origin((long)m);
2026   dfsan_set_label(j_label, &d, sizeof(d));
2027   dfsan_origin d_o = dfsan_get_origin((long)d);
2028 #ifndef ORIGIN_TRACKING
2029   (void)s_o;
2030   (void)m_o;
2031   (void)d_o;
2032 #endif
2033   int n;
2034   int r = sprintf(buf, "hello %s, %-d/%d/%d %f %% %n%d", s, 2014, m, d,
2035                   12345.6781234, &n, 1000);
2036   assert(r == 42);
2037   assert(strcmp(buf, "hello world, 2014/8/27 12345.678123 % 1000") == 0);
2038   ASSERT_READ_LABEL(buf, 7, 0);
2039   ASSERT_READ_LABEL(buf + 7, 2, k_label);
2040   ASSERT_INIT_ORIGINS(buf + 7, 2, s_o);
2041   ASSERT_READ_LABEL(buf + 9, 9, 0);
2042   ASSERT_READ_LABEL(buf + 18, 1, i_label);
2043   ASSERT_INIT_ORIGINS(buf + 18, 1, m_o);
2044   ASSERT_READ_LABEL(buf + 19, 1, 0);
2045   ASSERT_READ_LABEL(buf + 20, 2, j_label);
2046   ASSERT_INIT_ORIGINS(buf + 20, 2, d_o);
2047   ASSERT_READ_LABEL(buf + 22, 15, 0);
2048   ASSERT_LABEL(r, 0);
2049   assert(n == 38);
2050 
2051   // Test formatting & label propagation (single conversion specifier, with
2052   // additional length and precision modifiers).
2053   test_sprintf_chunk("-559038737", "%d", 0xdeadbeef);
2054   test_sprintf_chunk("3735928559", "%u", 0xdeadbeef);
2055   test_sprintf_chunk("12345", "%i", 12345);
2056   test_sprintf_chunk("751", "%o", 0751);
2057   test_sprintf_chunk("babe", "%x", 0xbabe);
2058   test_sprintf_chunk("0000BABE", "%.8X", 0xbabe);
2059   test_sprintf_chunk("-17", "%hhd", 0xdeadbeef);
2060   test_sprintf_chunk("-16657", "%hd", 0xdeadbeef);
2061   test_sprintf_chunk("deadbeefdeadbeef", "%lx", 0xdeadbeefdeadbeef);
2062   test_sprintf_chunk("0xdeadbeefdeadbeef", "%p",
2063                  (void *)  0xdeadbeefdeadbeef);
2064   test_sprintf_chunk("18446744073709551615", "%ju", (intmax_t) -1);
2065   test_sprintf_chunk("18446744073709551615", "%zu", (size_t) -1);
2066   test_sprintf_chunk("18446744073709551615", "%tu", (size_t) -1);
2067 
2068   test_sprintf_chunk("0x1.f9acffa7eb6bfp-4", "%a", 0.123456);
2069   test_sprintf_chunk("0X1.F9ACFFA7EB6BFP-4", "%A", 0.123456);
2070   test_sprintf_chunk("0.12346", "%.5f", 0.123456);
2071   test_sprintf_chunk("0.123456", "%g", 0.123456);
2072   test_sprintf_chunk("1.234560e-01", "%e", 0.123456);
2073   test_sprintf_chunk("1.234560E-01", "%E", 0.123456);
2074   test_sprintf_chunk("0.1234567891234560", "%.16Lf",
2075                      (long double) 0.123456789123456);
2076 
2077   test_sprintf_chunk("z", "%c", 'z');
2078 
2079   // %n, %s, %d, %f, and %% already tested
2080 
2081   // Test formatting with width passed as an argument.
2082   r = sprintf(buf, "hi %*d my %*s friend %.*f", 3, 1, 6, "dear", 4, 3.14159265359);
2083   assert(r == 30);
2084   assert(strcmp(buf, "hi   1 my   dear friend 3.1416") == 0);
2085 }
2086 
2087 void test_snprintf() {
2088   char buf[2048];
2089   memset(buf, 'a', sizeof(buf));
2090   dfsan_set_label(0, buf, sizeof(buf));
2091   const char* s = "world";
2092   int y = 2014;
2093   int m = 8;
2094   int d = 27;
2095   dfsan_set_label(k_label, (void *) (s + 1), 2);
2096   dfsan_origin s_o = dfsan_get_origin((long)(s[1]));
2097   dfsan_set_label(i_label, &y, sizeof(y));
2098   dfsan_origin y_o = dfsan_get_origin((long)y);
2099   dfsan_set_label(j_label, &m, sizeof(m));
2100   dfsan_origin m_o = dfsan_get_origin((long)m);
2101 #ifndef ORIGIN_TRACKING
2102   (void)s_o;
2103   (void)y_o;
2104   (void)m_o;
2105 #endif
2106   int r = snprintf(buf, 19, "hello %s, %-d/   %d/%d %f", s, y, m, d,
2107                    12345.6781234);
2108   // The return value is the number of bytes that would have been written to
2109   // the final string if enough space had been available.
2110   assert(r == 38);
2111   assert(memcmp(buf, "hello world, 2014/", 19) == 0);
2112   ASSERT_READ_LABEL(buf, 7, 0);
2113   ASSERT_READ_LABEL(buf + 7, 2, k_label);
2114   ASSERT_INIT_ORIGINS(buf + 7, 2, s_o);
2115   ASSERT_READ_LABEL(buf + 9, 4, 0);
2116   ASSERT_READ_LABEL(buf + 13, 4, i_label);
2117   ASSERT_INIT_ORIGINS(buf + 13, 4, y_o);
2118   ASSERT_READ_LABEL(buf + 17, 2, 0);
2119   ASSERT_LABEL(r, 0);
2120 }
2121 
2122 template <class T>
2123 void test_sscanf_chunk(T expected, const char *format, char *input,
2124                        int items_num) {
2125   char padded_input[512];
2126   strcpy(padded_input, "foo ");
2127   strcat(padded_input, input);
2128   strcpy(padded_input, "@");
2129   strcat(padded_input, input);
2130   strcat(padded_input, " bar");
2131 
2132   char padded_format[512];
2133   strcpy(padded_format, "foo ");
2134   // Swap the first '%' for '%*' so this input is skipped.
2135   strcpy(padded_format, "%*");
2136   strcat(padded_format, format + 1);
2137   strcpy(padded_format, "@");
2138   strcat(padded_format, format);
2139   strcat(padded_format, " bar");
2140 
2141   char *s = padded_input + 4;
2142   T arg;
2143   memset(&arg, 0, sizeof(arg));
2144   dfsan_set_label(i_label, (void *)(padded_input), strlen(padded_input));
2145   dfsan_set_label(j_label, (void *)(padded_format), strlen(padded_format));
2146   dfsan_origin a_o = dfsan_get_origin((long)(*s));
2147 #ifndef ORIGIN_TRACKING
2148   (void)a_o;
2149 #else
2150   assert(a_o != 0);
2151 #endif
2152   int rv = sscanf(padded_input, padded_format, &arg);
2153   assert(rv == items_num);
2154   assert(arg == expected);
2155   ASSERT_READ_LABEL(&arg, sizeof(arg), i_label);
2156   ASSERT_INIT_ORIGINS(&arg, 1, a_o);
2157 }
2158 
2159 void test_sscanf() {
2160   char buf[2048];
2161   char buf_out[2048];
2162   memset(buf, 'a', sizeof(buf));
2163   memset(buf_out, 'a', sizeof(buf_out));
2164 
2165   // Test formatting
2166   strcpy(buf, "Hello world!");
2167   assert(sscanf(buf, "%s", buf_out) == 1);
2168   assert(strcmp(buf, "Hello world!") == 0);
2169   assert(strcmp(buf_out, "Hello") == 0);
2170   ASSERT_READ_LABEL(buf, sizeof(buf), 0);
2171   ASSERT_READ_LABEL(buf_out, sizeof(buf_out), 0);
2172 
2173   // Test for extra arguments.
2174   assert(sscanf(buf, "%s", buf_out, 42, "hello") == 1);
2175   assert(strcmp(buf, "Hello world!") == 0);
2176   assert(strcmp(buf_out, "Hello") == 0);
2177   ASSERT_READ_LABEL(buf, sizeof(buf), 0);
2178   ASSERT_READ_LABEL(buf_out, sizeof(buf_out), 0);
2179 
2180   // Test formatting & label propagation (multiple conversion specifiers): %s,
2181   // %d, %n, %f, and %%.
2182   int n;
2183   strcpy(buf, "hello world, 42 2014/8/31 12345.678123 % 1000");
2184   char *s = buf + 6; //starts with world
2185   int y = 0;
2186   int m = 0;
2187   int d = 0;
2188   float fval;
2189   int val = 0;
2190   dfsan_set_label(k_label, (void *)(s + 1), 2); // buf[7]-b[9]
2191   dfsan_origin s_o = dfsan_get_origin((long)(s[1]));
2192   assert(s[10] == '2');
2193   dfsan_set_label(i_label, (void *)(s + 10), 4);    // 2014
2194   dfsan_origin y_o = dfsan_get_origin((long)s[10]); // buf[16]
2195   assert(s[17] == '3');
2196   dfsan_set_label(j_label, (void *)(s + 17), 2);    // 31
2197   dfsan_origin d_o = dfsan_get_origin((long)s[17]); // buf[23]
2198   assert(s[20] == '1');
2199   dfsan_set_label(m_label, (void *)(s + 20), 5);    // 12345
2200   dfsan_origin f_o = dfsan_get_origin((long)s[20]); //buf[26]
2201 
2202 #ifndef ORIGIN_TRACKING
2203   (void)s_o;
2204   (void)y_o;
2205   (void)d_o;
2206   (void)f_o;
2207 #else
2208   assert(s_o != 0);
2209   assert(y_o != 0);
2210   assert(d_o != 0);
2211   assert(f_o != 0);
2212 #endif
2213   int r = sscanf(buf, "hello %s %*d %d/%d/%d %f %% %n%d", buf_out, &y, &m, &d,
2214                  &fval, &n, &val);
2215   assert(r == 6);
2216   assert(strcmp(buf_out, "world,") == 0);
2217   assert(y == 2014);
2218   assert(m == 8);
2219   assert(d == 31);
2220   assert(fval > 12300.0f);
2221   assert(fval < 12400.0f);
2222   ASSERT_READ_LABEL(buf_out, 1, 0);
2223   ASSERT_READ_LABEL(buf_out + 1, 2, k_label);
2224   ASSERT_INIT_ORIGINS(buf_out + 1, 2, s_o);
2225   ASSERT_READ_LABEL(&y, sizeof(y), i_label);
2226   ASSERT_INIT_ORIGINS(&y, sizeof(y), y_o);
2227   ASSERT_READ_LABEL(&d, sizeof(d), j_label);
2228   ASSERT_INIT_ORIGINS(&d, sizeof(d), d_o);
2229   ASSERT_READ_LABEL(&fval, sizeof(fval), m_label);
2230   ASSERT_INIT_ORIGINS(&fval, sizeof(fval), f_o);
2231   ASSERT_READ_LABEL(&val, 4, 0);
2232   ASSERT_LABEL(r, 0);
2233   assert(n == 41);
2234   assert(val == 1000);
2235 
2236   // Test formatting & label propagation (single conversion specifier, with
2237   // additional length and precision modifiers).
2238   char input_buf[512];
2239   char *input_ptr = input_buf;
2240   strcpy(input_buf, "-559038737");
2241   test_sscanf_chunk(-559038737, "%d", input_ptr, 1);
2242   strcpy(input_buf, "3735928559");
2243   test_sscanf_chunk(3735928559, "%u", input_ptr, 1);
2244   strcpy(input_buf, "12345");
2245   test_sscanf_chunk(12345, "%i", input_ptr, 1);
2246   strcpy(input_buf, "0751");
2247   test_sscanf_chunk(489, "%o", input_ptr, 1);
2248   strcpy(input_buf, "0xbabe");
2249   test_sscanf_chunk(47806, "%x", input_ptr, 1);
2250   strcpy(input_buf, "0x0000BABE");
2251   test_sscanf_chunk(47806, "%10X", input_ptr, 1);
2252   strcpy(input_buf, "3735928559");
2253   test_sscanf_chunk((char)-17, "%hhd", input_ptr, 1);
2254   strcpy(input_buf, "3735928559");
2255   test_sscanf_chunk((short)-16657, "%hd", input_ptr, 1);
2256   strcpy(input_buf, "0xdeadbeefdeadbeef");
2257   test_sscanf_chunk(0xdeadbeefdeadbeefL, "%lx", input_buf, 1);
2258   test_sscanf_chunk((void *)0xdeadbeefdeadbeefL, "%p", input_buf, 1);
2259 
2260   intmax_t _x = (intmax_t)-1;
2261   char _buf[256];
2262   memset(_buf, 0, sizeof(_buf));
2263   sprintf(_buf, "%ju", _x);
2264   test_sscanf_chunk((intmax_t)18446744073709551615, "%ju", _buf, 1);
2265   memset(_buf, 0, sizeof(_buf));
2266   size_t _y = (size_t)-1;
2267   sprintf(_buf, "%zu", _y);
2268   test_sscanf_chunk((size_t)18446744073709551615, "%zu", _buf, 1);
2269   memset(_buf, 0, sizeof(_buf));
2270   ptrdiff_t _z = (size_t)-1;
2271   sprintf(_buf, "%tu", _z);
2272   test_sscanf_chunk((ptrdiff_t)18446744073709551615, "%tu", _buf, 1);
2273 
2274   strcpy(input_buf, "0.123456");
2275   test_sscanf_chunk((float)0.123456, "%8f", input_ptr, 1);
2276   test_sscanf_chunk((float)0.123456, "%g", input_ptr, 1);
2277   test_sscanf_chunk((float)1.234560e-01, "%e", input_ptr, 1);
2278   test_sscanf_chunk((char)'z', "%c", "z", 1);
2279 
2280   // %n, %s, %d, %f, and %% already tested
2281 }
2282 
2283 // Tested by a separate source file.  This empty function is here to appease the
2284 // check-wrappers script.
2285 void test_fork() {}
2286 
2287 int main(void) {
2288   i_label = 1;
2289   j_label = 2;
2290   k_label = 4;
2291   m_label = 8;
2292   n_label = 16;
2293   i_j_label = dfsan_union(i_label, j_label);
2294   assert(i_j_label != i_label);
2295   assert(i_j_label != j_label);
2296   assert(i_j_label != k_label);
2297 
2298   test__dl_get_tls_static_info();
2299   test_bcmp();
2300   test_clock_gettime();
2301   test_ctime_r();
2302   test_dfsan_set_write_callback();
2303   test_dl_iterate_phdr();
2304   test_dlopen();
2305   test_epoll_wait();
2306   test_fgets();
2307   test_fork();
2308   test_fstat();
2309   test_get_current_dir_name();
2310   test_getcwd();
2311   test_getentropy();
2312   test_gethostname();
2313   test_getpeername();
2314   test_getpwuid_r();
2315   test_getrlimit();
2316   test_getrusage();
2317   test_getsockname();
2318   test_getsockopt();
2319   test_gettimeofday();
2320   test_inet_pton();
2321   test_localtime_r();
2322   test_memchr();
2323   test_memcmp();
2324   test_memcpy();
2325   test_memmove();
2326   test_memset();
2327   test_nanosleep();
2328   test_poll();
2329   test_pread();
2330   test_pthread_create();
2331   test_pthread_join();
2332   test_read();
2333   test_recvmmsg();
2334   test_recvmsg();
2335   test_sched_getaffinity();
2336   test_select();
2337   test_sigaction();
2338   test_signal();
2339   test_sigaltstack();
2340   test_sigemptyset();
2341   test_snprintf();
2342   test_sscanf();
2343   test_socketpair();
2344   test_sprintf();
2345   test_stat();
2346   test_strcasecmp();
2347   test_strchr();
2348   test_strcmp();
2349   test_strcat();
2350   test_strncat(5);
2351   test_strncat(2);
2352   test_strcpy();
2353   test_strdup();
2354   test_strlen();
2355   test_strnlen();
2356   test_strncasecmp();
2357   test_strncmp();
2358   test_strncpy();
2359   test_strpbrk();
2360   test_strsep();
2361   test_strrchr();
2362   test_strstr();
2363   test_strtod();
2364   test_strtol();
2365   test_strtoll();
2366   test_strtoul();
2367   test_strtoull();
2368   test_time();
2369   test_write();
2370 }
2371