aboutsummaryrefslogtreecommitdiff
path: root/tests/matrix/matrix_test.go
blob: 574f11fe1dac40b29501075dbb0261cd12a551df (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
// Tests run for (almost all) combinations of openssl, aessiv, plaintextnames.
package matrix

// File reading, writing, modification, truncate
//
// Runs everything four times, for all combinations of
// "-plaintextnames" and "-openssl".
//
// Test Matrix:
//                       openssl=true openssl=false
// plaintextnames=false  X            X
// plaintextnames=true   X            X

import (
	"bytes"
	"flag"
	"fmt"
	"io/ioutil"
	"os"
	"os/exec"
	"runtime"
	"sync"
	"syscall"
	"testing"

	"github.com/rfjakob/gocryptfs/internal/stupidgcm"
	"github.com/rfjakob/gocryptfs/internal/syscallcompat"
	"github.com/rfjakob/gocryptfs/tests/test_helpers"
)

// Several tests need to be aware if plaintextnames is active or not, so make this
// a global variable
var testcase testcaseMatrix

type testcaseMatrix struct {
	plaintextnames bool
	openssl        string
	aessiv         bool
	raw64          bool
}

var matrix = []testcaseMatrix{
	// Normal
	{false, "auto", false, false},
	{false, "true", false, false},
	{false, "false", false, false},
	// Plaintextnames
	{true, "true", false, false},
	{true, "false", false, false},
	// AES-SIV (does not use openssl, no need to test permutations)
	{false, "auto", true, false},
	{true, "auto", true, false},
	// Raw64
	{false, "auto", false, true},
}

// This is the entry point for the tests
func TestMain(m *testing.M) {
	// Make "testing.Verbose()" return the correct value
	flag.Parse()
	for _, testcase = range matrix {
		if testcase.openssl == "true" && stupidgcm.BuiltWithoutOpenssl {
			continue
		}
		if testing.Verbose() {
			fmt.Printf("matrix: testcase = %#v\n", testcase)
		}
		test_helpers.ResetTmpDir(!testcase.plaintextnames)
		opts := []string{"-zerokey"}
		opts = append(opts, fmt.Sprintf("-openssl=%v", testcase.openssl))
		opts = append(opts, fmt.Sprintf("-plaintextnames=%v", testcase.plaintextnames))
		opts = append(opts, fmt.Sprintf("-aessiv=%v", testcase.aessiv))
		opts = append(opts, fmt.Sprintf("-raw64=%v", testcase.raw64))
		test_helpers.MountOrExit(test_helpers.DefaultCipherDir, test_helpers.DefaultPlainDir, opts...)
		r := m.Run()
		test_helpers.UnmountPanic(test_helpers.DefaultPlainDir)
		if r != 0 {
			os.Exit(r)
		}
	}
	os.Exit(0)
}

// Write "n" zero bytes to filename "fn", read again, compare hash
func testWriteN(t *testing.T, fn string, n int) string {
	file, err := os.Create(test_helpers.DefaultPlainDir + "/" + fn)
	if err != nil {
		t.Fatal(err)
	}

	d := make([]byte, n)
	written, err := file.Write(d)
	if err != nil || written != len(d) {
		t.Errorf("err=\"%s\", written=%d", err, written)
	}
	err = file.Close()
	if err != nil {
		t.Error(err)
	}

	test_helpers.VerifySize(t, test_helpers.DefaultPlainDir+"/"+fn, n)

	hashWant := test_helpers.Md5hex(d)

	hashActual := test_helpers.Md5fn(test_helpers.DefaultPlainDir + "/" + fn)

	if hashActual != hashWant {
		t.Errorf("Wrong content, hashWant=%s hashActual=%s", hashWant, hashActual)
	}

	return hashActual
}

func TestWrite10(t *testing.T) {
	testWriteN(t, "10", 10)
}

func TestWrite100(t *testing.T) {
	testWriteN(t, "100", 100)
}

func TestWrite1M(t *testing.T) {
	testWriteN(t, "1M", 1024*1024)
}

func TestWrite100x100(t *testing.T) {
	hashWant := testWriteN(t, "100x100", 100)
	// Read and check 100 times to catch race conditions
	var i int
	for i = 0; i < 100; i++ {
		hashActual := test_helpers.Md5fn(test_helpers.DefaultPlainDir + "/100")
		if hashActual != hashWant {
			fmt.Printf("Read corruption in loop #%d\n", i)
			t.FailNow()
		} else {
			//fmt.Print(".")
		}
	}
}

// Hint for calculating reference md5sums:
// dd if=/dev/zero count=1 bs=XYZ | md5sum
func TestTruncate(t *testing.T) {
	fn := test_helpers.DefaultPlainDir + "/truncate"
	file, err := os.Create(fn)
	if err != nil {
		t.FailNow()
	}
	// Grow to two blocks
	file.Truncate(7000)
	test_helpers.VerifySize(t, fn, 7000)
	if md5 := test_helpers.Md5fn(fn); md5 != "95d4ec7038e3e4fdbd5f15c34c3f0b34" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Shrink - needs RMW
	file.Truncate(6999)
	test_helpers.VerifySize(t, fn, 6999)
	if md5 := test_helpers.Md5fn(fn); md5 != "35fd15873ec6c35380064a41b9b9683b" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Shrink to one partial block
	file.Truncate(465)
	test_helpers.VerifySize(t, fn, 465)
	if md5 := test_helpers.Md5fn(fn); md5 != "a1534d6e98a6b21386456a8f66c55260" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Grow to exactly one block
	file.Truncate(4096)
	test_helpers.VerifySize(t, fn, 4096)
	if md5 := test_helpers.Md5fn(fn); md5 != "620f0b67a91f7f74151bc5be745b7110" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Truncate to zero
	file.Truncate(0)
	test_helpers.VerifySize(t, fn, 0)
	// Grow to 10MB (creates file holes)
	var sz int
	sz = 10 * 1024 * 1024
	file.Truncate(int64(sz))
	test_helpers.VerifySize(t, fn, sz)
	if md5 := test_helpers.Md5fn(fn); md5 != "f1c9645dbc14efddc7d8a322685f26eb" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Grow to 10MB + 100B (partial block on the end)
	sz = 10*1024*1024 + 100
	file.Truncate(int64(sz))
	test_helpers.VerifySize(t, fn, sz)
	if md5 := test_helpers.Md5fn(fn); md5 != "c23ea79b857b91a7ff07c6ecf185f1ca" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Grow to 20MB (creates file holes, partial block on the front)
	sz = 20 * 1024 * 1024
	file.Truncate(int64(sz))
	test_helpers.VerifySize(t, fn, sz)
	if md5 := test_helpers.Md5fn(fn); md5 != "8f4e33f3dc3e414ff94e5fb6905cba8c" {
		t.Errorf("Wrong md5 %s", md5)
	}
}

const (
	// From man statfs
	TMPFS_MAGIC      = 0x01021994
	EXT4_SUPER_MAGIC = 0xef53
)

// isWellKnownFS decides if the backing filesystem is well-known.
// The expected allocated sizes are only valid on tmpfs and ext4. btrfs
// gives different results, but that's not an error.
func isWellKnownFS(fn string) bool {
	var fs syscall.Statfs_t
	err := syscall.Statfs(fn, &fs)
	if err != nil {
		panic(err)
	}
	if fs.Type == EXT4_SUPER_MAGIC || fs.Type == TMPFS_MAGIC {
		return true
	}
	return false
}

const FALLOC_DEFAULT = 0x00
const FALLOC_FL_KEEP_SIZE = 0x01

func TestFallocate(t *testing.T) {
	if runtime.GOOS == "darwin" {
		t.Skipf("OSX does not support fallocate")
	}
	fn := test_helpers.DefaultPlainDir + "/fallocate"
	file, err := os.Create(fn)
	if err != nil {
		t.FailNow()
	}
	wellKnown := isWellKnownFS(test_helpers.DefaultCipherDir)
	fd := int(file.Fd())
	nBytes := test_helpers.Du(t, fd)
	if nBytes != 0 {
		t.Fatalf("Empty file has %d bytes", nBytes)
	}
	// Allocate 30 bytes, keep size
	// gocryptfs ||        (0 blocks)
	//      ext4 |  d   |  (1 block)
	err = syscallcompat.Fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 30)
	if err != nil {
		t.Error(err)
	}
	var want int64
	nBytes = test_helpers.Du(t, fd)
	want = 4096
	if nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	test_helpers.VerifySize(t, fn, 0)
	// Three ciphertext blocks. The middle one should be a file hole.
	// gocryptfs |  h   |   h  | d|   (1 block)
	//      ext4 |  d  |  h  |  d  |  (2 blocks)
	// (Note that gocryptfs blocks are slightly bigger than the ext4 blocks,
	// but the last one is partial)
	err = file.Truncate(9000)
	if err != nil {
		t.Fatal(err)
	}
	nBytes = test_helpers.Du(t, fd)
	want = 2 * 4096
	if wellKnown && nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	if md5 := test_helpers.Md5fn(fn); md5 != "5420afa22f6423a9f59e669540656bb4" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Allocate the whole file space
	// gocryptfs |  h   |   h  | d|   (1 block)
	//      ext4 |  d  |  d  |  d  |  (3 blocks
	err = syscallcompat.Fallocate(fd, FALLOC_DEFAULT, 0, 9000)
	if err != nil {
		t.Fatal(err)
	}
	nBytes = test_helpers.Du(t, fd)
	want = 3 * 4096
	if nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	// Neither apparent size nor content should have changed
	test_helpers.VerifySize(t, fn, 9000)
	if md5 := test_helpers.Md5fn(fn); md5 != "5420afa22f6423a9f59e669540656bb4" {
		t.Errorf("Wrong md5 %s", md5)
	}

	// Partial block on the end. The first ext4 block is dirtied by the header.
	// gocryptfs |  h   |   h  | d|   (1 block)
	//      ext4 |  d  |  h  |  d  |  (2 blocks)
	file.Truncate(0)
	file.Truncate(9000)
	nBytes = test_helpers.Du(t, fd)
	want = 2 * 4096
	if wellKnown && nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	// Allocate 10 bytes in the second block
	// gocryptfs |  h   |   h  | d|   (1 block)
	//      ext4 |  d  |  d  |  d  |  (3 blocks)
	syscallcompat.Fallocate(fd, FALLOC_DEFAULT, 5000, 10)
	nBytes = test_helpers.Du(t, fd)
	want = 3 * 4096
	if wellKnown && nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	// Neither apparent size nor content should have changed
	test_helpers.VerifySize(t, fn, 9000)
	if md5 := test_helpers.Md5fn(fn); md5 != "5420afa22f6423a9f59e669540656bb4" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Grow the file to 4 blocks
	// gocryptfs |  h   |  h   |  d   |d|  (2 blocks)
	//      ext4 |  d  |  d  |  d  |  d  | (4 blocks)
	syscallcompat.Fallocate(fd, FALLOC_DEFAULT, 15000, 10)
	nBytes = test_helpers.Du(t, fd)
	want = 4 * 4096
	if wellKnown && nBytes != want {
		t.Errorf("Expected %d allocated bytes, have %d", want, nBytes)
	}
	test_helpers.VerifySize(t, fn, 15010)
	if md5 := test_helpers.Md5fn(fn); md5 != "c4c44c7a41ab7798a79d093eb44f99fc" {
		t.Errorf("Wrong md5 %s", md5)
	}
	// Shrinking a file using fallocate should have no effect
	for _, off := range []int64{0, 10, 2000, 5000} {
		for _, sz := range []int64{0, 1, 42, 6000} {
			syscallcompat.Fallocate(fd, FALLOC_DEFAULT, off, sz)
			test_helpers.VerifySize(t, fn, 15010)
			if md5 := test_helpers.Md5fn(fn); md5 != "c4c44c7a41ab7798a79d093eb44f99fc" {
				t.Errorf("Wrong md5 %s", md5)
			}
		}
	}
	// Cleanup
	file.Close()
	syscall.Unlink(fn)
	if !wellKnown {
		// Even though most tests have been executed still, inform the user
		// that some were disabled
		t.Skipf("backing fs is not ext4 or tmpfs, skipped some disk-usage checks\n")
	}
}

func TestAppend(t *testing.T) {
	fn := test_helpers.DefaultPlainDir + "/append"
	file, err := os.Create(fn)
	if err != nil {
		t.FailNow()
	}
	data := []byte("testdata123456789") // length 17
	var buf bytes.Buffer
	var hashWant string
	for i := 0; i <= 500; i++ {
		file.Write(data)
		buf.Write(data)
		hashWant = test_helpers.Md5hex(buf.Bytes())
		hashActual := test_helpers.Md5fn(fn)
		if hashWant != hashActual {
			t.FailNow()
		}
	}

	// Overwrite with the same data
	// Hash must stay the same
	file.Seek(0, 0)
	for i := 0; i <= 500; i++ {
		file.Write(data)
		hashActual := test_helpers.Md5fn(fn)
		if hashWant != hashActual {
			t.FailNow()
		}
	}
}

// Create a file with holes by writing to offset 0 (block #0) and
// offset 4096 (block #1).
func TestFileHoles(t *testing.T) {
	fn := test_helpers.DefaultPlainDir + "/fileholes"
	file, err := os.Create(fn)
	if err != nil {
		t.Errorf("file create failed")
	}
	foo := []byte("foo")
	file.Write(foo)
	file.WriteAt(foo, 4096)
	_, err = ioutil.ReadFile(fn)
	if err != nil {
		t.Error(err)
	}
}

// sContains - does the slice of strings "haystack" contain "needle"?
func sContains(haystack []string, needle string) bool {
	for _, element := range haystack {
		if element == needle {
			return true
		}
	}
	return false
}

func TestRmwRace(t *testing.T) {

	runtime.GOMAXPROCS(10)

	fn := test_helpers.DefaultPlainDir + "/rmwrace"
	f1, err := os.Create(fn)
	if err != nil {
		t.Fatalf("file create failed")
	}
	defer f1.Close()
	f2, err := os.Create(fn)
	if err != nil {
		t.Fatalf("file create failed")
	}
	defer f2.Close()

	oldBlock := bytes.Repeat([]byte("o"), 4096)

	newBlock := bytes.Repeat([]byte("n"), 4096)

	shortBlock := bytes.Repeat([]byte("s"), 16)

	mergedBlock := make([]byte, 4096)
	copy(mergedBlock, newBlock)
	copy(mergedBlock[4080:], shortBlock)

	goodMd5 := make(map[string]int)

	for i := 0; i < 1000; i++ {
		// Reset to [ooooooooo]
		_, err = f1.WriteAt(oldBlock, 0)
		if err != nil {
			t.Fatalf("Write failed")
		}

		var wg sync.WaitGroup
		wg.Add(2)

		// Write to the end of the file, [....ssss]
		go func() {
			f1.WriteAt(shortBlock, 4080)
			wg.Done()
		}()

		// Overwrite to [nnnnnnn]
		go func() {
			f2.WriteAt(newBlock, 0)
			wg.Done()
		}()

		wg.Wait()

		// The file should be either:
		// [nnnnnnnnnn] (md5: 6c1660fdabccd448d1359f27b3db3c99) or
		// [nnnnnnssss] (md5: da885006a6a284530a427c73ce1e5c32)
		// but it must not be
		// [oooooossss]

		buf, _ := ioutil.ReadFile(fn)
		m := test_helpers.Md5hex(buf)
		goodMd5[m] = goodMd5[m] + 1

		/*
			if m == "6c1660fdabccd448d1359f27b3db3c99" {
				fmt.Println(hex.Dump(buf))
				t.FailNow()
			}
		*/
	}
}

// With "--plaintextnames", the name "/gocryptfs.conf" is reserved.
// Otherwise there should be no restrictions.
func TestFiltered(t *testing.T) {
	filteredFile := test_helpers.DefaultPlainDir + "/gocryptfs.conf"
	file, err := os.Create(filteredFile)
	if testcase.plaintextnames && err == nil {
		t.Errorf("should have failed but didn't")
	} else if !testcase.plaintextnames && err != nil {
		t.Error(err)
	}
	file.Close()

	err = os.Remove(filteredFile)
	if testcase.plaintextnames && err == nil {
		t.Errorf("should have failed but didn't")
	} else if !testcase.plaintextnames && err != nil {
		t.Error(err)
	}
}

func TestFilenameEncryption(t *testing.T) {
	file, err := os.Create(test_helpers.DefaultPlainDir + "/TestFilenameEncryption.txt")
	file.Close()
	if err != nil {
		t.Fatal(err)
	}
	_, err = os.Stat(test_helpers.DefaultCipherDir + "/TestFilenameEncryption.txt")
	if testcase.plaintextnames && err != nil {
		t.Errorf("plaintextnames not working: %v", err)
	} else if !testcase.plaintextnames && err == nil {
		t.Errorf("file name encryption not working")
	}
}

// Test Mkdir and Rmdir
func testMkdirRmdir(t *testing.T) {
	test_helpers.TestMkdirRmdir(t, test_helpers.DefaultPlainDir)
}

// Test Rename
func testRename(t *testing.T) {
	test_helpers.TestRename(t, test_helpers.DefaultPlainDir)
}

// Overwrite an empty directory with another directory
func TestDirOverwrite(t *testing.T) {
	dir1 := test_helpers.DefaultPlainDir + "/DirOverwrite1"
	dir2 := test_helpers.DefaultPlainDir + "/DirOverwrite2"
	err := os.Mkdir(dir1, 0777)
	if err != nil {
		t.Fatal(err)
	}
	err = os.Mkdir(dir2, 0777)
	if err != nil {
		t.Fatal(err)
	}
	err = syscall.Rename(dir1, dir2)
	if err != nil {
		t.Fatal(err)
	}
}

func TestLongNames(t *testing.T) {
	fi, err := ioutil.ReadDir(test_helpers.DefaultCipherDir)
	if err != nil {
		t.Fatal(err)
	}
	cnt1 := len(fi)
	wd := test_helpers.DefaultPlainDir + "/"
	// Create file with long name
	n255x := string(bytes.Repeat([]byte("x"), 255))
	f, err := os.Create(wd + n255x)
	if err != nil {
		t.Fatalf("Could not create n255x: %v", err)
	}
	f.Close()
	if !test_helpers.VerifyExistence(wd + n255x) {
		t.Errorf("n255x is not in directory listing")
	}
	// Rename long to long (target does not exist)
	n255y := string(bytes.Repeat([]byte("y"), 255))
	err = os.Rename(wd+n255x, wd+n255y)
	if err != nil {
		t.Fatalf("Could not rename n255x to n255y: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + n255y) {
		t.Errorf("n255y is not in directory listing")
	}
	// Rename long to long (target exists)
	f, err = os.Create(wd + n255x)
	if err != nil {
		t.Fatalf("Could not create n255x: %v", err)
	}
	f.Close()
	err = os.Rename(wd+n255x, wd+n255y)
	if err != nil {
		t.Fatalf("Could not rename n255x to n255y: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + n255y) {
		t.Errorf("n255y is not in directory listing")
	}
	// Rename long to short (target does not exist)
	err = os.Rename(wd+n255y, wd+"short")
	if err != nil {
		t.Fatalf("Could not rename n255y to short: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + "short") {
		t.Errorf("short is not in directory listing")
	}
	// Rename long to short (target exists)
	f, err = os.Create(wd + n255y)
	if err != nil {
		t.Fatalf("Could not create n255y: %v", err)
	}
	f.Close()
	err = os.Rename(wd+n255y, wd+"short")
	if err != nil {
		t.Fatalf("Could not rename n255y to short: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + "short") {
		t.Errorf("short is not in directory listing")
	}
	// Rename short to long (target does not exist)
	err = os.Rename(wd+"short", wd+n255x)
	if err != nil {
		t.Fatalf("Could not rename short to n255x: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + n255x) {
		t.Errorf("255x is not in directory listing II")
	}
	// Rename short to long (target exists)
	f, err = os.Create(wd + "short")
	if err != nil {
		t.Fatalf("Could not create short: %v", err)
	}
	f.Close()
	err = os.Rename(wd+"short", wd+n255x)
	if err != nil {
		t.Fatalf("Could not rename short to n255x: %v", err)
	}
	if !test_helpers.VerifyExistence(wd + n255x) {
		t.Errorf("n255x is not in directory listing")
	}
	// Unlink
	err = syscall.Unlink(wd + n255x)
	if err != nil {
		t.Fatalf("Could not unlink n255x: %v", err)
	}
	if test_helpers.VerifyExistence(wd + n255x) {
		t.Errorf("n255x still there after unlink")
	}
	// Long symlink
	n255s := string(bytes.Repeat([]byte("s"), 255))
	err = os.Symlink("/", wd+n255s)
	if err != nil {
		t.Fatal(err)
	}
	if !test_helpers.VerifyExistence(wd + n255s) {
		t.Errorf("n255s is not in directory listing")
	}
	err = syscall.Unlink(wd + n255s)
	if err != nil {
		t.Error(err)
	}
	// Long dir
	n255d := string(bytes.Repeat([]byte("d"), 255))
	err = os.Mkdir(wd+n255d, 0777)
	if err != nil {
		t.Fatal(err)
	}
	err = syscall.Rmdir(wd + n255d)
	if err != nil {
		t.Error(err)
	}
	// Check for orphaned files
	fi, err = ioutil.ReadDir(test_helpers.DefaultCipherDir)
	if err != nil {
		t.Fatal(err)
	}
	cnt2 := len(fi)
	if cnt1 != cnt2 {
		t.Errorf("Leftover files, cnt1=%d cnt2=%d", cnt1, cnt2)
	}
}

// Create hard link with long name.
// This was broken up to v1.2.
func TestLongLink(t *testing.T) {
	wd := test_helpers.DefaultPlainDir + "/"
	target := wd + "TestLongLink.target"
	f, err := os.Create(target)
	if err != nil {
		t.Fatalf("%v", err)
	}
	f.Close()
	l255 := string(bytes.Repeat([]byte("l"), 255))
	err = os.Link(target, wd+l255)
	if err != nil {
		t.Error(err)
	}
}

func TestLchown(t *testing.T) {
	name := test_helpers.DefaultPlainDir + "/symlink"
	err := os.Symlink("/target/does/not/exist", name)
	if err != nil {
		t.Fatal(err)
	}
	err = os.Chown(name, os.Getuid(), os.Getgid())
	if err == nil {
		t.Error("Chown on dangling symlink should fail")
	}
	err = os.Lchown(name, os.Getuid(), os.Getgid())
	if err != nil {
		t.Error(err)
	}
}

// Set nanoseconds by path, symlink
func Symlink(t *testing.T) {
	if runtime.GOOS == "darwin" {
		t.Skipf("MacOS \"touch\" does not support \"--no-dereference\"")
	}
	path := test_helpers.DefaultPlainDir + "/utimesnano_symlink"
	err := os.Symlink("/some/nonexisting/file", path)
	if err != nil {
		t.Fatal(err)
	}
	// syscall.UtimesNano does not provide a way to pass AT_SYMLINK_NOFOLLOW,
	// so we call the external utility "touch", which does.
	cmd := exec.Command("touch", "--no-dereference", path)
	cmd.Stderr = os.Stderr
	cmd.Stdout = os.Stdout
	err = cmd.Run()
	if err != nil {
		t.Error(err)
	}
}

type utimesTestcaseStruct struct {
	// Input atime and mtime
	in [2]syscall.Timespec
	// Expected output atime and mtime
	out [2]syscall.Timespec
}

// compareTimespec return true if the two passed Timespec are identical.
func compareTimespec(want syscall.Timespec, actual syscall.Timespec) bool {
	if want.Sec != actual.Sec {
		return false
	}
	if want.Nsec != actual.Nsec {
		return false
	}
	return true
}

const _UTIME_OMIT = ((1 << 30) - 2)

// doTestUtimesNano verifies that setting nanosecond-precision times on "path"
// works correctly. Pass "/proc/self/fd/N" to test a file descriptor.
func doTestUtimesNano(t *testing.T, path string) {
	utimeTestcases := []utimesTestcaseStruct{
		{
			in:  [2]syscall.Timespec{{Sec: 50, Nsec: 0}, {Sec: 51, Nsec: 0}},
			out: [2]syscall.Timespec{{Sec: 50, Nsec: 0}, {Sec: 51, Nsec: 0}},
		},
		{
			in:  [2]syscall.Timespec{{Sec: 1, Nsec: 2}, {Sec: 3, Nsec: 4}},
			out: [2]syscall.Timespec{{Sec: 1, Nsec: 2}, {Sec: 3, Nsec: 4}},
		},
		{
			in:  [2]syscall.Timespec{{Sec: 7, Nsec: 8}, {Sec: 99, Nsec: _UTIME_OMIT}},
			out: [2]syscall.Timespec{{Sec: 7, Nsec: 8}, {Sec: 3, Nsec: 4}},
		},
		{
			in:  [2]syscall.Timespec{{Sec: 99, Nsec: _UTIME_OMIT}, {Sec: 5, Nsec: 6}},
			out: [2]syscall.Timespec{{Sec: 7, Nsec: 8}, {Sec: 5, Nsec: 6}},
		},
	}
	if runtime.GOOS == "darwin" {
		// darwin neither supports UTIME_OMIT nor nanoseconds (!?)
		utimeTestcases = utimeTestcases[:1]
	}
	for i, tc := range utimeTestcases {
		err := syscall.UtimesNano(path, tc.in[:])
		if err != nil {
			t.Fatal(err)
		}
		var st syscall.Stat_t
		err = syscall.Stat(path, &st)
		if err != nil {
			t.Fatal(err)
		}
		want := tc.out
		have := extractAtimeMtime(st)
		if !compareTimespec(want[0], have[0]) {
			t.Errorf("Testcase %d: atime: want=%+v, have=%+v", i, want[0], have[0])
		}
		if !compareTimespec(want[1], have[1]) {
			t.Errorf("Testcase %d: mtime: want=%+v, have=%+v", i, want[1], have[1])
		}
	}
}

// Set nanoseconds by path, normal file
func TestUtimesNano(t *testing.T) {
	path := test_helpers.DefaultPlainDir + "/utimesnano"
	err := ioutil.WriteFile(path, []byte("foobar"), 0600)
	if err != nil {
		t.Fatal(err)
	}
	doTestUtimesNano(t, path)
}

// Set nanoseconds by fd
func TestUtimesNanoFd(t *testing.T) {
	if runtime.GOOS == "darwin" {
		t.Skipf("MacOS does not have /proc")
	}
	path := test_helpers.DefaultPlainDir + "/utimesnanofd"
	f, err := os.Create(path)
	if err != nil {
		t.Fatal(err)
	}
	defer f.Close()
	procPath := fmt.Sprintf("/proc/self/fd/%d", f.Fd())
	doTestUtimesNano(t, procPath)
}

// Make sure the Mknod call works by creating a fifo (named pipe)
func TestMkfifo(t *testing.T) {
	path := test_helpers.DefaultPlainDir + "/fifo1"
	err := syscall.Mkfifo(path, 0700)
	if err != nil {
		t.Fatal(err)
	}
	path = test_helpers.DefaultPlainDir + "/gocryptfs.longname.XXX"
	err = syscall.Mkfifo(path, 0700)
	if err != nil {
		t.Fatal(err)
	}
	err = os.Remove(path)
	if err != nil {
		t.Fatal(err)
	}
}

// TestMagicNames verifies that "magic" names are handled correctly
// https://github.com/rfjakob/gocryptfs/issues/174
func TestMagicNames(t *testing.T) {
	names := []string{"gocryptfs.longname.QhUr5d9FHerwEs--muUs6_80cy6JRp89c1otLwp92Cs", "gocryptfs.diriv"}
	for _, n := range names {
		t.Logf("Testing n=%q", n)
		p := test_helpers.DefaultPlainDir + "/" + n
		// Create file
		err := ioutil.WriteFile(p, []byte("xxxxxxx"), 0200)
		if err != nil {
			t.Fatalf("creating file %q failed: %v", n, err)
		}
		// Rename magic to normal
		err = os.Rename(p, test_helpers.DefaultPlainDir+"/x")
		if err != nil {
			t.Fatalf("rename 1 failed: %v", err)
		}
		// Rename normal to magic
		err = os.Rename(test_helpers.DefaultPlainDir+"/x", p)
		if err != nil {
			t.Fatalf("rename 2 failed: %v", err)
		}
		// Unlink
		err = syscall.Unlink(p)
		if err != nil {
			t.Fatal(err)
		}
		// Mkdir
		err = os.Mkdir(p, 0700)
		if err != nil {
			t.Fatal(err)
		}
		// Rmdir
		err = syscall.Rmdir(p)
		if err != nil {
			t.Fatal(err)
		}
		// Symlink
		err = syscall.Symlink("xxxyyyyzzz", p)
		if err != nil {
			t.Fatal(err)
		}
		syscall.Unlink(p)
		// Link
		target := test_helpers.DefaultPlainDir + "/linktarget"
		err = ioutil.WriteFile(target, []byte("yyyyy"), 0200)
		if err != nil {
			t.Fatal(err)
		}
		err = syscall.Link(target, p)
		if err != nil {
			t.Fatal(err)
		}
	}
}