aboutsummaryrefslogtreecommitdiffstats
path: root/tests/dlext_test.cpp
blob: 97b52080f5045f0897cf0076649e721c25adb4e4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
/*
 * Copyright (C) 2014 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <gtest/gtest.h>

#include <dlfcn.h>
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <android/dlext.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/wait.h>

#include <pagemap/pagemap.h>

#include "TemporaryFile.h"
#include "utils.h"

#define ASSERT_DL_NOTNULL(ptr) \
    ASSERT_TRUE(ptr != nullptr) << "dlerror: " << dlerror()

#define ASSERT_DL_ZERO(i) \
    ASSERT_EQ(0, i) << "dlerror: " << dlerror()

#define ASSERT_NOERROR(i) \
    ASSERT_NE(-1, i) << "errno: " << strerror(errno)

#define ASSERT_SUBSTR(needle, haystack) \
    ASSERT_PRED_FORMAT2(::testing::IsSubstring, needle, haystack)


typedef int (*fn)(void);
#define LIBNAME "libdlext_test.so"
#define LIBNAME_NORELRO "libdlext_test_norelro.so"
#define LIBSIZE 1024*1024 // how much address space to reserve for it

#if defined(__LP64__)
#define NATIVE_TESTS_PATH "/nativetest64"
#else
#define NATIVE_TESTS_PATH "/nativetest"
#endif

#define LIBPATH NATIVE_TESTS_PATH "/libdlext_test_fd/libdlext_test_fd.so"
#define LIBZIPPATH NATIVE_TESTS_PATH "/libdlext_test_zip/libdlext_test_zip_zipaligned.zip"
#define LIBZIPPATH_WITH_RUNPATH NATIVE_TESTS_PATH "/libdlext_test_runpath_zip/libdlext_test_runpath_zip_zipaligned.zip"

#define LIBZIP_OFFSET PAGE_SIZE

class DlExtTest : public ::testing::Test {
protected:
  virtual void SetUp() {
    handle_ = nullptr;
    // verify that we don't have the library loaded already
    void* h = dlopen(LIBNAME, RTLD_NOW | RTLD_NOLOAD);
    ASSERT_TRUE(h == nullptr);
    h = dlopen(LIBNAME_NORELRO, RTLD_NOW | RTLD_NOLOAD);
    ASSERT_TRUE(h == nullptr);
    // call dlerror() to swallow the error, and check it was the one we wanted
    ASSERT_STREQ("dlopen failed: library \"" LIBNAME_NORELRO "\" wasn't loaded and RTLD_NOLOAD prevented it", dlerror());
  }

  virtual void TearDown() {
    if (handle_ != nullptr) {
      ASSERT_DL_ZERO(dlclose(handle_));
    }
  }

  void* handle_;
};

TEST_F(DlExtTest, ExtInfoNull) {
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, nullptr);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, ExtInfoNoFlags) {
  android_dlextinfo extinfo;
  extinfo.flags = 0;
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, ExtInfoUseFd) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBPATH;

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD;
  extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
  ASSERT_TRUE(extinfo.library_fd != -1);
  handle_ = android_dlopen_ext(lib_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_EQ(4, f());

  uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
  ASSERT_DL_NOTNULL(taxicab_number);
  EXPECT_EQ(1729U, *taxicab_number);
}

TEST_F(DlExtTest, ExtInfoUseFdWithOffset) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH;

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
  extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
  extinfo.library_fd_offset = LIBZIP_OFFSET;

  handle_ = android_dlopen_ext(lib_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);

  uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
  ASSERT_DL_NOTNULL(taxicab_number);
  EXPECT_EQ(1729U, *taxicab_number);
}

TEST_F(DlExtTest, ExtInfoUseFdWithInvalidOffset) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH;
  // lib_path is relative when $ANDROID_DATA is relative
  char lib_realpath_buf[PATH_MAX];
  ASSERT_TRUE(realpath(lib_path.c_str(), lib_realpath_buf) == lib_realpath_buf);
  const std::string lib_realpath = std::string(lib_realpath_buf);

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD | ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
  extinfo.library_fd = TEMP_FAILURE_RETRY(open(lib_path.c_str(), O_RDONLY | O_CLOEXEC));
  extinfo.library_fd_offset = 17;

  handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
  ASSERT_STREQ("dlopen failed: file offset for the library \"libname_placeholder\" is not page-aligned: 17", dlerror());

  // Test an address above 2^44, for http://b/18178121 .
  extinfo.library_fd_offset = (5LL<<48) + PAGE_SIZE;
  handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
  ASSERT_SUBSTR("dlopen failed: file offset for the library \"libname_placeholder\" >= file size", dlerror());

  extinfo.library_fd_offset = 0LL - PAGE_SIZE;
  handle_ = android_dlopen_ext("libname_placeholder", RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
  ASSERT_SUBSTR("dlopen failed: file offset for the library \"libname_placeholder\" is negative", dlerror());

  extinfo.library_fd_offset = 0;
  handle_ = android_dlopen_ext("libname_ignored", RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
  ASSERT_EQ("dlopen failed: \"" + lib_realpath + "\" has bad ELF magic", dlerror());

  // Check if dlsym works after unsuccessful dlopen().
  // Supply non-exiting one to make linker visit every soinfo.
  void* sym = dlsym(RTLD_DEFAULT, "this_symbol_does_not_exist___");
  ASSERT_TRUE(sym == nullptr);

  close(extinfo.library_fd);
}

TEST_F(DlExtTest, ExtInfoUseOffsetWihtoutFd) {
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET;
  extinfo.library_fd_offset = LIBZIP_OFFSET;

  handle_ = android_dlopen_ext("/some/lib/that/does_not_exist", RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
  ASSERT_STREQ("dlopen failed: invalid extended flag combination (ANDROID_DLEXT_USE_LIBRARY_FD_OFFSET without ANDROID_DLEXT_USE_LIBRARY_FD): 0x20", dlerror());
}

TEST(dlext, android_dlopen_ext_force_load_smoke) {
  // 1. Open actual file
  void* handle = dlopen("libdlext_test.so", RTLD_NOW);
  ASSERT_DL_NOTNULL(handle);
  // 2. Open link with force_load flag set
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_FORCE_LOAD;
  void* handle2 = android_dlopen_ext("libdlext_test_v2.so", RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle2);
  ASSERT_TRUE(handle != handle2);

  dlclose(handle2);
  dlclose(handle);
}

TEST(dlext, android_dlopen_ext_force_load_soname_exception) {
  // Check if soname lookup still returns already loaded library
  // when ANDROID_DLEXT_FORCE_LOAD flag is specified.
  void* handle = dlopen("libdlext_test_v2.so", RTLD_NOW);
  ASSERT_DL_NOTNULL(handle);

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_FORCE_LOAD;

  // Note that 'libdlext_test.so' is dt_soname for libdlext_test_v2.so
  void* handle2 = android_dlopen_ext("libdlext_test.so", RTLD_NOW, &extinfo);

  ASSERT_DL_NOTNULL(handle2);
  ASSERT_TRUE(handle == handle2);

  dlclose(handle2);
  dlclose(handle);
}

TEST(dlfcn, dlopen_from_zip_absolute_path) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH;

  void* handle = dlopen((lib_path + "!/libdir/libatest_simple_zip.so").c_str(), RTLD_NOW);
  ASSERT_TRUE(handle != nullptr) << dlerror();

  uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
  ASSERT_DL_NOTNULL(taxicab_number);
  EXPECT_EQ(1729U, *taxicab_number);

  dlclose(handle);
}

TEST(dlfcn, dlopen_from_zip_with_dt_runpath) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH_WITH_RUNPATH;

  void* handle = dlopen((lib_path + "!/libdir/libtest_dt_runpath_d_zip.so").c_str(), RTLD_NOW);

  ASSERT_TRUE(handle != nullptr) << dlerror();

  typedef void *(* dlopen_b_fn)();
  dlopen_b_fn fn = (dlopen_b_fn)dlsym(handle, "dlopen_b");
  ASSERT_TRUE(fn != nullptr) << dlerror();

  void *p = fn();
  ASSERT_TRUE(p != nullptr) << dlerror();

  dlclose(p);
  dlclose(handle);
}

TEST(dlfcn, dlopen_from_zip_ld_library_path) {
  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + LIBZIPPATH + "!/libdir";

  typedef void (*fn_t)(const char*);
  fn_t android_update_LD_LIBRARY_PATH =
      reinterpret_cast<fn_t>(dlsym(RTLD_DEFAULT, "android_update_LD_LIBRARY_PATH"));

  ASSERT_TRUE(android_update_LD_LIBRARY_PATH != nullptr) << dlerror();

  void* handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
  ASSERT_TRUE(handle == nullptr);

  android_update_LD_LIBRARY_PATH(lib_path.c_str());

  handle = dlopen("libdlext_test_zip.so", RTLD_NOW);
  ASSERT_TRUE(handle != nullptr) << dlerror();

  int (*fn)(void);
  fn = reinterpret_cast<int (*)(void)>(dlsym(handle, "getRandomNumber"));
  ASSERT_TRUE(fn != nullptr);
  EXPECT_EQ(4, fn());

  uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle, "dlopen_testlib_taxicab_number"));
  ASSERT_DL_NOTNULL(taxicab_number);
  EXPECT_EQ(1729U, *taxicab_number);

  dlclose(handle);
}


TEST_F(DlExtTest, Reserved) {
  void* start = mmap(nullptr, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                     -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
  extinfo.reserved_addr = start;
  extinfo.reserved_size = LIBSIZE;
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_GE(reinterpret_cast<void*>(f), start);
  EXPECT_LT(reinterpret_cast<void*>(f),
            reinterpret_cast<char*>(start) + LIBSIZE);
  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, ReservedTooSmall) {
  void* start = mmap(nullptr, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                     -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
  extinfo.reserved_addr = start;
  extinfo.reserved_size = PAGE_SIZE;
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  EXPECT_EQ(nullptr, handle_);
}

TEST_F(DlExtTest, ReservedHint) {
  void* start = mmap(nullptr, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                     -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
  extinfo.reserved_addr = start;
  extinfo.reserved_size = LIBSIZE;
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_GE(reinterpret_cast<void*>(f), start);
  EXPECT_LT(reinterpret_cast<void*>(f),
            reinterpret_cast<char*>(start) + LIBSIZE);
  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, ReservedHintTooSmall) {
  void* start = mmap(nullptr, PAGE_SIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                     -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_RESERVED_ADDRESS_HINT;
  extinfo.reserved_addr = start;
  extinfo.reserved_size = PAGE_SIZE;
  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_TRUE(reinterpret_cast<void*>(f) < start ||
              (reinterpret_cast<void*>(f) >=
               reinterpret_cast<char*>(start) + PAGE_SIZE));
  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, LoadAtFixedAddress) {
  void* start = mmap(nullptr, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                     -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  munmap(start, LIBSIZE);

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS;
  extinfo.reserved_addr = start;

  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_DL_NOTNULL(handle_);
  fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
  ASSERT_DL_NOTNULL(f);
  EXPECT_GE(reinterpret_cast<void*>(f), start);
  EXPECT_LT(reinterpret_cast<void*>(f), reinterpret_cast<char*>(start) + LIBSIZE);

  EXPECT_EQ(4, f());
}

TEST_F(DlExtTest, LoadAtFixedAddressTooSmall) {
  void* start = mmap(nullptr, LIBSIZE + PAGE_SIZE, PROT_NONE,
                         MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  ASSERT_TRUE(start != MAP_FAILED);
  munmap(start, LIBSIZE + PAGE_SIZE);
  void* new_addr = mmap(reinterpret_cast<uint8_t*>(start) + PAGE_SIZE, LIBSIZE, PROT_NONE,
                        MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
  ASSERT_TRUE(new_addr != MAP_FAILED);

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_LOAD_AT_FIXED_ADDRESS;
  extinfo.reserved_addr = start;

  handle_ = android_dlopen_ext(LIBNAME, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle_ == nullptr);
}

class DlExtRelroSharingTest : public DlExtTest {
protected:
  virtual void SetUp() {
    DlExtTest::SetUp();
    void* start = mmap(nullptr, LIBSIZE, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS,
                       -1, 0);
    ASSERT_TRUE(start != MAP_FAILED);
    extinfo_.flags = ANDROID_DLEXT_RESERVED_ADDRESS;
    extinfo_.reserved_addr = start;
    extinfo_.reserved_size = LIBSIZE;
    extinfo_.relro_fd = -1;
  }

  virtual void TearDown() {
    DlExtTest::TearDown();
  }

  void CreateRelroFile(const char* lib, const char* relro_file) {
    int relro_fd = open(relro_file, O_RDWR | O_TRUNC);
    ASSERT_NOERROR(relro_fd);

    pid_t pid = fork();
    if (pid == 0) {
      // child process
      extinfo_.flags |= ANDROID_DLEXT_WRITE_RELRO;
      extinfo_.relro_fd = relro_fd;
      void* handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
      if (handle == nullptr) {
        fprintf(stderr, "in child: %s\n", dlerror());
        exit(1);
      }
      exit(0);
    }

    // continuing in parent
    ASSERT_NOERROR(close(relro_fd));
    ASSERT_NOERROR(pid);
    int status;
    ASSERT_EQ(pid, waitpid(pid, &status, 0));
    ASSERT_TRUE(WIFEXITED(status));
    ASSERT_EQ(0, WEXITSTATUS(status));

    // reopen file for reading so it can be used
    relro_fd = open(relro_file, O_RDONLY);
    ASSERT_NOERROR(relro_fd);
    extinfo_.flags |= ANDROID_DLEXT_USE_RELRO;
    extinfo_.relro_fd = relro_fd;
  }

  void TryUsingRelro(const char* lib) {
    handle_ = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
    ASSERT_DL_NOTNULL(handle_);
    fn f = reinterpret_cast<fn>(dlsym(handle_, "getRandomNumber"));
    ASSERT_DL_NOTNULL(f);
    EXPECT_EQ(4, f());

    uint32_t* taxicab_number = reinterpret_cast<uint32_t*>(dlsym(handle_, "dlopen_testlib_taxicab_number"));
    ASSERT_DL_NOTNULL(taxicab_number);
    EXPECT_EQ(1729U, *taxicab_number);
  }

  void SpawnChildrenAndMeasurePss(const char* lib, bool share_relro, size_t* pss_out);

  android_dlextinfo extinfo_;
};

TEST_F(DlExtRelroSharingTest, ChildWritesGoodData) {
  TemporaryFile tf; // Use tf to get an unique filename.
  ASSERT_NOERROR(close(tf.fd));

  ASSERT_NO_FATAL_FAILURE(CreateRelroFile(LIBNAME, tf.filename));
  ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME));

  // Use destructor of tf to close and unlink the file.
  tf.fd = extinfo_.relro_fd;
}

TEST_F(DlExtRelroSharingTest, ChildWritesNoRelro) {
  TemporaryFile tf; // // Use tf to get an unique filename.
  ASSERT_NOERROR(close(tf.fd));

  ASSERT_NO_FATAL_FAILURE(CreateRelroFile(LIBNAME_NORELRO, tf.filename));
  ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME_NORELRO));

  // Use destructor of tf to close and unlink the file.
  tf.fd = extinfo_.relro_fd;
}

TEST_F(DlExtRelroSharingTest, RelroFileEmpty) {
  ASSERT_NO_FATAL_FAILURE(TryUsingRelro(LIBNAME));
}

TEST_F(DlExtRelroSharingTest, VerifyMemorySaving) {
  if (geteuid() != 0) {
    GTEST_LOG_(INFO) << "This test must be run as root.\n";
    return;
  }

  TemporaryFile tf; // Use tf to get an unique filename.
  ASSERT_NOERROR(close(tf.fd));

  ASSERT_NO_FATAL_FAILURE(CreateRelroFile(LIBNAME, tf.filename));

  int pipefd[2];
  ASSERT_NOERROR(pipe(pipefd));

  size_t without_sharing, with_sharing;
  ASSERT_NO_FATAL_FAILURE(SpawnChildrenAndMeasurePss(LIBNAME, false, &without_sharing));
  ASSERT_NO_FATAL_FAILURE(SpawnChildrenAndMeasurePss(LIBNAME, true, &with_sharing));

  // We expect the sharing to save at least 10% of the total PSS. In practice
  // it saves 40%+ for this test.
  size_t expected_size = without_sharing - (without_sharing/10);
  EXPECT_LT(with_sharing, expected_size);

  // Use destructor of tf to close and unlink the file.
  tf.fd = extinfo_.relro_fd;
}

void getPss(pid_t pid, size_t* pss_out) {
  pm_kernel_t* kernel;
  ASSERT_EQ(0, pm_kernel_create(&kernel));

  pm_process_t* process;
  ASSERT_EQ(0, pm_process_create(kernel, pid, &process));

  pm_map_t** maps;
  size_t num_maps;
  ASSERT_EQ(0, pm_process_maps(process, &maps, &num_maps));

  size_t total_pss = 0;
  for (size_t i = 0; i < num_maps; i++) {
    pm_memusage_t usage;
    ASSERT_EQ(0, pm_map_usage(maps[i], &usage));
    total_pss += usage.pss;
  }
  *pss_out = total_pss;

  free(maps);
  pm_process_destroy(process);
  pm_kernel_destroy(kernel);
}

void DlExtRelroSharingTest::SpawnChildrenAndMeasurePss(const char* lib, bool share_relro,
                                                       size_t* pss_out) {
  const int CHILDREN = 20;

  // Create children
  pid_t childpid[CHILDREN];
  int childpipe[CHILDREN];
  for (int i=0; i<CHILDREN; ++i) {
    char read_buf;
    int child_done_pipe[2], parent_done_pipe[2];
    ASSERT_NOERROR(pipe(child_done_pipe));
    ASSERT_NOERROR(pipe(parent_done_pipe));

    pid_t child = fork();
    if (child == 0) {
      // close the 'wrong' ends of the pipes in the child
      close(child_done_pipe[0]);
      close(parent_done_pipe[1]);

      // open the library
      void* handle;
      if (share_relro) {
        handle = android_dlopen_ext(lib, RTLD_NOW, &extinfo_);
      } else {
        handle = dlopen(lib, RTLD_NOW);
      }
      if (handle == nullptr) {
        fprintf(stderr, "in child: %s\n", dlerror());
        exit(1);
      }

      // close write end of child_done_pipe to signal the parent that we're done.
      close(child_done_pipe[1]);

      // wait for the parent to close parent_done_pipe, then exit
      read(parent_done_pipe[0], &read_buf, 1);
      exit(0);
    }

    ASSERT_NOERROR(child);

    // close the 'wrong' ends of the pipes in the parent
    close(child_done_pipe[1]);
    close(parent_done_pipe[0]);

    // wait for the child to be done
    read(child_done_pipe[0], &read_buf, 1);
    close(child_done_pipe[0]);

    // save the child's pid and the parent_done_pipe
    childpid[i] = child;
    childpipe[i] = parent_done_pipe[1];
  }

  // Sum the PSS of all the children
  size_t total_pss = 0;
  for (int i=0; i<CHILDREN; ++i) {
    size_t child_pss;
    ASSERT_NO_FATAL_FAILURE(getPss(childpid[i], &child_pss));
    total_pss += child_pss;
  }
  *pss_out = total_pss;

  // Close pipes and wait for children to exit
  for (int i=0; i<CHILDREN; ++i) {
    ASSERT_NOERROR(close(childpipe[i]));
  }
  for (int i=0; i<CHILDREN; ++i) {
    int status;
    ASSERT_EQ(childpid[i], waitpid(childpid[i], &status, 0));
    ASSERT_TRUE(WIFEXITED(status));
    ASSERT_EQ(0, WEXITSTATUS(status));
  }
}

// Testing namespaces
static const char* g_public_lib = "libnstest_public.so";

TEST(dlext, ns_smoke) {
  static const char* root_lib = "libnstest_root.so";
  std::string path = std::string("libc.so:libc++.so:libdl.so:libm.so:") + g_public_lib;

  ASSERT_FALSE(android_init_namespaces(path.c_str(), nullptr));
  ASSERT_STREQ("android_init_namespaces failed: error initializing public namespace: "
               "\"libnstest_public.so\" was not found in the default namespace", dlerror());

  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + NATIVE_TESTS_PATH;

  const std::string lib_public_path = lib_path + "/public_namespace_libs/" + g_public_lib;
  void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
  ASSERT_TRUE(handle_public != nullptr) << dlerror();

  ASSERT_TRUE(android_init_namespaces(path.c_str(), nullptr)) << dlerror();

  // Check that libraries added to public namespace are NODELETE
  dlclose(handle_public);
  handle_public = dlopen((lib_path + "/public_namespace_libs/" + g_public_lib).c_str(), RTLD_NOW | RTLD_NOLOAD);
  ASSERT_TRUE(handle_public != nullptr) << dlerror();

  android_namespace_t* ns1 = android_create_namespace("private", nullptr, (lib_path + "/private_namespace_libs").c_str(), false);
  ASSERT_TRUE(ns1 != nullptr) << dlerror();

  android_namespace_t* ns2 = android_create_namespace("private_isolated", nullptr, (lib_path + "/private_namespace_libs").c_str(), true);
  ASSERT_TRUE(ns2 != nullptr) << dlerror();

  // This should not have affect search path for default namespace:
  ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
  void* handle = dlopen(g_public_lib, RTLD_NOW);
  ASSERT_TRUE(handle != nullptr) << dlerror();
  dlclose(handle);

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
  extinfo.library_namespace = ns1;

  void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle1 != nullptr) << dlerror();

  extinfo.library_namespace = ns2;
  void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle2 != nullptr) << dlerror();

  ASSERT_TRUE(handle1 != handle2);

  // dlopen for a public library using an absolute path should work for isolated namespaces
  extinfo.library_namespace = ns2;
  handle = android_dlopen_ext(lib_public_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle != nullptr) << dlerror();
  ASSERT_TRUE(handle == handle_public);

  dlclose(handle);

  typedef const char* (*fn_t)();

  fn_t ns_get_local_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
  ASSERT_TRUE(ns_get_local_string1 != nullptr) << dlerror();
  fn_t ns_get_local_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_local_string"));
  ASSERT_TRUE(ns_get_local_string2 != nullptr) << dlerror();

  EXPECT_STREQ("This string is local to root library", ns_get_local_string1());
  EXPECT_STREQ("This string is local to root library", ns_get_local_string2());

  ASSERT_TRUE(ns_get_local_string1() != ns_get_local_string2());

  fn_t ns_get_private_extern_string1 =
          reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
  ASSERT_TRUE(ns_get_private_extern_string1 != nullptr) << dlerror();
  fn_t ns_get_private_extern_string2 =
          reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_private_extern_string"));
  ASSERT_TRUE(ns_get_private_extern_string2 != nullptr) << dlerror();

  EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string1());
  EXPECT_STREQ("This string is from private namespace", ns_get_private_extern_string2());

  ASSERT_TRUE(ns_get_private_extern_string1() != ns_get_private_extern_string2());

  fn_t ns_get_public_extern_string1 =
          reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
  ASSERT_TRUE(ns_get_public_extern_string1 != nullptr) << dlerror();
  fn_t ns_get_public_extern_string2 =
          reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_public_extern_string"));
  ASSERT_TRUE(ns_get_public_extern_string2 != nullptr) << dlerror();

  EXPECT_STREQ("This string is from public namespace", ns_get_public_extern_string1());
  ASSERT_TRUE(ns_get_public_extern_string1() == ns_get_public_extern_string2());

  // and now check that dlopen() does the right thing in terms of preserving namespace
  fn_t ns_get_dlopened_string1 = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
  ASSERT_TRUE(ns_get_dlopened_string1 != nullptr) << dlerror();
  fn_t ns_get_dlopened_string2 = reinterpret_cast<fn_t>(dlsym(handle2, "ns_get_dlopened_string"));
  ASSERT_TRUE(ns_get_dlopened_string2 != nullptr) << dlerror();

  EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string1());
  EXPECT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());

  ASSERT_TRUE(ns_get_dlopened_string1() != ns_get_dlopened_string2());

  dlclose(handle1);

  // Check if handle2 is still alive (and well)
  ASSERT_STREQ("This string is local to root library", ns_get_local_string2());
  ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string2());
  ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string2());
  ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string2());

  dlclose(handle2);
}

extern "C" void android_set_application_target_sdk_version(uint32_t target);

TEST(dlext, ns_isolated) {
  static const char* root_lib = "libnstest_root_not_isolated.so";
  std::string path = std::string("libc.so:libc++.so:libdl.so:libm.so:") + g_public_lib;

  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + NATIVE_TESTS_PATH;
  const std::string lib_public_path = lib_path + "/public_namespace_libs/" + g_public_lib;
  void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);
  ASSERT_TRUE(handle_public != nullptr) << dlerror();

  android_set_application_target_sdk_version(42U); // something > 23

  ASSERT_TRUE(android_init_namespaces(path.c_str(), nullptr)) << dlerror();

  android_namespace_t* ns_not_isolated = android_create_namespace("private", nullptr, (lib_path + "/private_namespace_libs").c_str(), false);
  ASSERT_TRUE(ns_not_isolated != nullptr) << dlerror();

  android_namespace_t* ns_isolated = android_create_namespace("private_isolated1", nullptr, (lib_path + "/private_namespace_libs").c_str(), true);
  ASSERT_TRUE(ns_isolated != nullptr) << dlerror();

  android_namespace_t* ns_isolated2 = android_create_namespace("private_isolated2", (lib_path + "/private_namespace_libs").c_str(), nullptr, true);
  ASSERT_TRUE(ns_isolated2 != nullptr) << dlerror();

  ASSERT_TRUE(dlopen(root_lib, RTLD_NOW) == nullptr);
  ASSERT_STREQ("dlopen failed: library \"libnstest_root_not_isolated.so\" not found", dlerror());

  std::string lib_private_external_path =
      lib_path + "/private_namespace_libs_external/libnstest_private_external.so";

  // Load lib_private_external_path to default namespace
  // (it should remain invisible for the isolated namespaces after this)
  void* handle = dlopen(lib_private_external_path.c_str(), RTLD_NOW);
  ASSERT_TRUE(handle != nullptr) << dlerror();

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
  extinfo.library_namespace = ns_not_isolated;

  void* handle1 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle1 != nullptr) << dlerror();

  extinfo.library_namespace = ns_isolated;

  void* handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle2 == nullptr);
  ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());

  // Check dlopen by absolute path
  handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle2 == nullptr);
  ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" is not accessible for the namespace \"private_isolated1\"", dlerror());

  extinfo.library_namespace = ns_isolated2;

  handle2 = android_dlopen_ext(root_lib, RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle2 == nullptr);
  ASSERT_STREQ("dlopen failed: library \"libnstest_private_external.so\" not found", dlerror());

  // Check dlopen by absolute path
  handle2 = android_dlopen_ext(lib_private_external_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle2 == nullptr);
  ASSERT_EQ("dlopen failed: library \"" + lib_private_external_path + "\" is not accessible for the namespace \"private_isolated2\"", dlerror());

  typedef const char* (*fn_t)();
  fn_t ns_get_local_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_local_string"));
  ASSERT_TRUE(ns_get_local_string != nullptr) << dlerror();

  ASSERT_STREQ("This string is local to root library", ns_get_local_string());

  fn_t ns_get_private_extern_string =
          reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_private_extern_string"));
  ASSERT_TRUE(ns_get_private_extern_string != nullptr) << dlerror();

  ASSERT_STREQ("This string is from private namespace", ns_get_private_extern_string());

  fn_t ns_get_public_extern_string =
          reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_public_extern_string"));
  ASSERT_TRUE(ns_get_public_extern_string != nullptr) << dlerror();

  ASSERT_STREQ("This string is from public namespace", ns_get_public_extern_string());

  fn_t ns_get_dlopened_string = reinterpret_cast<fn_t>(dlsym(handle1, "ns_get_dlopened_string"));
  ASSERT_TRUE(ns_get_dlopened_string != nullptr) << dlerror();

  ASSERT_STREQ("This string is from private namespace (dlopened library)", ns_get_dlopened_string());

  dlclose(handle1);
}

TEST(dlext, ns_anonymous) {
  static const char* root_lib = "libnstest_root.so";
  std::string path = std::string("libc.so:libc++.so:libdl.so:libm.so:") + g_public_lib;

  const std::string lib_path = std::string(getenv("ANDROID_DATA")) + NATIVE_TESTS_PATH;

  const std::string lib_public_path = lib_path + "/public_namespace_libs/" + g_public_lib;
  void* handle_public = dlopen(lib_public_path.c_str(), RTLD_NOW);

  ASSERT_TRUE(handle_public != nullptr) << dlerror();

  ASSERT_TRUE(android_init_namespaces(path.c_str(), (lib_path + "/private_namespace_libs").c_str()))
      << dlerror();

  android_namespace_t* ns = android_create_namespace(
                                "private", nullptr,
                                (lib_path + "/private_namespace_libs").c_str(),
                                false);

  ASSERT_TRUE(ns != nullptr) << dlerror();

  std::string private_library_absolute_path = lib_path + "/private_namespace_libs/" + root_lib;

  android_dlextinfo extinfo;
  extinfo.flags = ANDROID_DLEXT_USE_NAMESPACE;
  extinfo.library_namespace = ns;

  // we are going to copy this library to anonymous mmap and call the copy of ns_get_dlopened_string
  void* handle = android_dlopen_ext(private_library_absolute_path.c_str(), RTLD_NOW, &extinfo);
  ASSERT_TRUE(handle != nullptr) << dlerror();

  uintptr_t ns_get_dlopened_string_addr =
      reinterpret_cast<uintptr_t>(dlsym(handle, "ns_get_dlopened_string"));
  ASSERT_TRUE(ns_get_dlopened_string_addr != 0) << dlerror();
  typedef const char* (*fn_t)();
  fn_t ns_get_dlopened_string_private = reinterpret_cast<fn_t>(ns_get_dlopened_string_addr);

  std::vector<map_record> maps;
  Maps::parse_maps(&maps);

  uintptr_t addr_start = 0;
  uintptr_t addr_end = 0;
  std::vector<map_record> maps_to_copy;

  for (const auto& rec : maps) {
    if (rec.pathname == private_library_absolute_path) {
      if (addr_start == 0) {
        addr_start = rec.addr_start;
      }
      addr_end = rec.addr_end;

      maps_to_copy.push_back(rec);
    }
  }

  // some sanity checks..
  ASSERT_TRUE(addr_start > 0);
  ASSERT_TRUE(addr_end > 0);
  ASSERT_EQ(3U, maps_to_copy.size());
  ASSERT_TRUE(ns_get_dlopened_string_addr > addr_start);
  ASSERT_TRUE(ns_get_dlopened_string_addr < addr_end);

  // copy
  uintptr_t reserved_addr = reinterpret_cast<uintptr_t>(mmap(nullptr, addr_end - addr_start,
                                                             PROT_NONE, MAP_ANON | MAP_PRIVATE,
                                                             -1, 0));
  ASSERT_TRUE(reinterpret_cast<void*>(reserved_addr) != MAP_FAILED);

  for (const auto& rec : maps_to_copy) {
    uintptr_t offset = rec.addr_start - addr_start;
    size_t size = rec.addr_end - rec.addr_start;
    void* addr = reinterpret_cast<void*>(reserved_addr + offset);
    void* map = mmap(addr, size, PROT_READ | PROT_WRITE,
                     MAP_ANON | MAP_PRIVATE | MAP_FIXED, -1, 0);
    ASSERT_TRUE(map != MAP_FAILED);
    memcpy(map, reinterpret_cast<void*>(rec.addr_start), size);
    mprotect(map, size, rec.perms);
  }

  // call the function copy
  uintptr_t ns_get_dlopened_string_offset  = ns_get_dlopened_string_addr - addr_start;
  fn_t ns_get_dlopened_string_anon = reinterpret_cast<fn_t>(reserved_addr + ns_get_dlopened_string_offset);
  ASSERT_STREQ("This string is from private namespace (dlopened library)",
               ns_get_dlopened_string_anon());

  // They should belong to different namespaces (private and anonymous)
  ASSERT_STREQ("This string is from private namespace (dlopened library)",
               ns_get_dlopened_string_private());

  ASSERT_TRUE(ns_get_dlopened_string_anon() != ns_get_dlopened_string_private());
}