diff options
-rw-r--r-- | internal/fusefrontend_reverse/reverse_longnames.go | 11 | ||||
-rw-r--r-- | tests/example_filesystems/example_filesystems_test.go | 2 | ||||
-rw-r--r-- | tests/reverse/correctness_test.go | 36 |
3 files changed, 30 insertions, 19 deletions
diff --git a/internal/fusefrontend_reverse/reverse_longnames.go b/internal/fusefrontend_reverse/reverse_longnames.go index ec164f1..3bfe3af 100644 --- a/internal/fusefrontend_reverse/reverse_longnames.go +++ b/internal/fusefrontend_reverse/reverse_longnames.go @@ -17,7 +17,14 @@ import ( ) const ( - shortNameMax = 176 + // File names are padded to 16-byte multiples, encrypted and + // base64-encoded. We can encode at most 176 bytes to stay below the 255 + // bytes limit: + // * base64(176 bytes) = 235 bytes + // * base64(192 bytes) = 256 bytes (over 255!) + // But the PKCS#7 padding is at least one byte. This means we can only use + // 175 bytes for the file name. + shortNameMax = 175 ) var longnameParentCache map[string]string @@ -57,6 +64,7 @@ func (rfs *ReverseFS) findLongnameParent(dir string, dirIV []byte, longname stri } dirEntries, err := dirfd.Readdirnames(-1) if err != nil { + tlog.Warn.Printf("findLongnameParent: Readdirnames failed: %v\n", err) return "", err } longnameCacheLock.Lock() @@ -78,7 +86,6 @@ func (rfs *ReverseFS) findLongnameParent(dir string, dirIV []byte, longname stri if hit == "" { return "", syscall.ENOENT } - return hit, nil } diff --git a/tests/example_filesystems/example_filesystems_test.go b/tests/example_filesystems/example_filesystems_test.go index cbea251..0732eb6 100644 --- a/tests/example_filesystems/example_filesystems_test.go +++ b/tests/example_filesystems/example_filesystems_test.go @@ -254,6 +254,8 @@ func TestExampleFSv13(t *testing.T) { // gocryptfs v1.3 introduced HKDF. // We check the md5 sum of the encrypted version of a file to make sure we don't // accidentially change the ciphertext generation. +// Create a full crypto round-trip by mounting two times: +// dirA -> reverse mount -> dirB -> forward mount -> dirC func TestExampleFSv13reverse(t *testing.T) { // Prepare directories dirA := "v1.3-reverse" diff --git a/tests/reverse/correctness_test.go b/tests/reverse/correctness_test.go index a5719eb..40b53f9 100644 --- a/tests/reverse/correctness_test.go +++ b/tests/reverse/correctness_test.go @@ -1,6 +1,7 @@ package reverse_test import ( + "bytes" "io/ioutil" "os" "syscall" @@ -10,25 +11,26 @@ import ( "github.com/rfjakob/gocryptfs/tests/test_helpers" ) +// TestLongnameStat checks that file names of all sizes (1 to 255) show up in +// the decrypted reverse view (dirC, mounted in TestMain). func TestLongnameStat(t *testing.T) { - fd, err := os.Create(dirA + "/" + x240) - if err != nil { - t.Fatal(err) - } - path := dirC + "/" + x240 - if !test_helpers.VerifyExistence(path) { - t.Fail() - } - test_helpers.VerifySize(t, path, 0) - _, err = fd.Write(make([]byte, 10)) - if err != nil { - t.Fatal(err) + for i := 1; i <= 255; i++ { + name := string(bytes.Repeat([]byte("x"), i)) + fd, err := os.Create(dirA + "/" + name) + if err != nil { + t.Fatal(err) + } + fd.Close() + path := dirC + "/" + name + if !test_helpers.VerifyExistence(path) { + t.Fail() + } + test_helpers.VerifySize(t, path, 0) + // A large number of longname files is a performance problem in + // reverse mode. Delete the file once we are done with it to speed up + // the test (2 seconds -> 0.2 seconds) + syscall.Unlink(dirA + "/" + name) } - fd.Close() - /* - time.Sleep(1000 * time.Millisecond) - test_helpers.VerifySize(t, path, 10) - */ } func TestSymlinks(t *testing.T) { |