Major refactoring: Split up "cryptfs" into several internal packages

"git status" for reference:

deleted:    cryptfs/cryptfs.go
deleted:    cryptfs/names_core.go
modified:   integration_tests/cli_test.go
modified:   integration_tests/helpers.go
renamed:    cryptfs/config_file.go -> internal/configfile/config_file.go
renamed:    cryptfs/config_test.go -> internal/configfile/config_test.go
renamed:    cryptfs/config_test/.gitignore -> internal/configfile/config_test/.gitignore
renamed:    cryptfs/config_test/PlaintextNames.conf -> internal/configfile/config_test/PlaintextNames.conf
renamed:    cryptfs/config_test/StrangeFeature.conf -> internal/configfile/config_test/StrangeFeature.conf
renamed:    cryptfs/config_test/v1.conf -> internal/configfile/config_test/v1.conf
renamed:    cryptfs/config_test/v2.conf -> internal/configfile/config_test/v2.conf
renamed:    cryptfs/kdf.go -> internal/configfile/kdf.go
renamed:    cryptfs/kdf_test.go -> internal/configfile/kdf_test.go
renamed:    cryptfs/cryptfs_content.go -> internal/contentenc/content.go
new file:   internal/contentenc/content_api.go
renamed:    cryptfs/content_test.go -> internal/contentenc/content_test.go
renamed:    cryptfs/file_header.go -> internal/contentenc/file_header.go
renamed:    cryptfs/intrablock.go -> internal/contentenc/intrablock.go
renamed:    cryptfs/address_translation.go -> internal/contentenc/offsets.go
new file:   internal/cryptocore/crypto_api.go
renamed:    cryptfs/gcm_go1.4.go -> internal/cryptocore/gcm_go1.4.go
renamed:    cryptfs/gcm_go1.5.go -> internal/cryptocore/gcm_go1.5.go
renamed:    cryptfs/nonce.go -> internal/cryptocore/nonce.go
renamed:    cryptfs/openssl_aead.go -> internal/cryptocore/openssl_aead.go
renamed:    cryptfs/openssl_benchmark.bash -> internal/cryptocore/openssl_benchmark.bash
renamed:    cryptfs/openssl_test.go -> internal/cryptocore/openssl_test.go
new file:   internal/nametransform/name_api.go
new file:   internal/nametransform/names_core.go
renamed:    cryptfs/names_diriv.go -> internal/nametransform/names_diriv.go
renamed:    cryptfs/names_noiv.go -> internal/nametransform/names_noiv.go
renamed:    cryptfs/names_test.go -> internal/nametransform/names_test.go
new file:   internal/nametransform/pad16.go
renamed:    cryptfs/log.go -> internal/toggledlog/log.go
renamed:    cryptfs/log_go1.4.go -> internal/toggledlog/log_go1.4.go
renamed:    cryptfs/log_go1.5.go -> internal/toggledlog/log_go1.5.go
modified:   main.go
modified:   masterkey.go
modified:   pathfs_frontend/file.go
modified:   pathfs_frontend/file_holes.go
modified:   pathfs_frontend/fs.go
modified:   pathfs_frontend/fs_dir.go
modified:   pathfs_frontend/names.go
modified:   test.bash

1 files changed, 91 insertions, 0 deletions

diff --git a/internal/contentenc/content_test.go b/internal/contentenc/content_test.go
new file mode 100644
index 0000000..70ad58d
--- /dev/null
+++ b/internal/contentenc/content_test.go
@@ -0,0 +1,91 @@
+package contentenc
+
+import (
+	"testing"
+)
+
+type testRange struct {
+	offset uint64
+	length uint64
+}
+
+func TestSplitRange(t *testing.T) {
+	var ranges []testRange
+
+	ranges = append(ranges, testRange{0, 70000},
+		testRange{0, 10},
+		testRange{234, 6511},
+		testRange{65444, 54},
+		testRange{0, 1024 * 1024},
+		testRange{0, 65536},
+		testRange{6654, 8945})
+
+	key := make([]byte, KEY_LEN)
+	f := NewCryptFS(key, true, false, true)
+
+	for _, r := range ranges {
+		parts := f.ExplodePlainRange(r.offset, r.length)
+		var lastBlockNo uint64 = 1 << 63
+		for _, p := range parts {
+			if p.BlockNo == lastBlockNo {
+				t.Errorf("Duplicate block number %d", p.BlockNo)
+			}
+			lastBlockNo = p.BlockNo
+			if p.Length > DEFAULT_PLAINBS || p.Skip >= DEFAULT_PLAINBS {
+				t.Errorf("Test fail: n=%d, length=%d, offset=%d\n", p.BlockNo, p.Length, p.Skip)
+			}
+		}
+	}
+}
+
+func TestCiphertextRange(t *testing.T) {
+	var ranges []testRange
+
+	ranges = append(ranges, testRange{0, 70000},
+		testRange{0, 10},
+		testRange{234, 6511},
+		testRange{65444, 54},
+		testRange{6654, 8945})
+
+	key := make([]byte, KEY_LEN)
+	f := NewCryptFS(key, true, false, true)
+
+	for _, r := range ranges {
+
+		blocks := f.ExplodePlainRange(r.offset, r.length)
+		alignedOffset, alignedLength := blocks[0].JointCiphertextRange(blocks)
+		skipBytes := blocks[0].Skip
+
+		if alignedLength < r.length {
+			t.Errorf("alignedLength=%d is smaller than length=%d", alignedLength, r.length)
+		}
+		if (alignedOffset-HEADER_LEN)%f.cipherBS != 0 {
+			t.Errorf("alignedOffset=%d is not aligned", alignedOffset)
+		}
+		if r.offset%f.plainBS != 0 && skipBytes == 0 {
+			t.Errorf("skipBytes=0")
+		}
+	}
+}
+
+func TestBlockNo(t *testing.T) {
+	key := make([]byte, KEY_LEN)
+	f := NewCryptFS(key, true, false, true)
+
+	b := f.CipherOffToBlockNo(788)
+	if b != 0 {
+		t.Errorf("actual: %d", b)
+	}
+	b = f.CipherOffToBlockNo(HEADER_LEN + f.cipherBS)
+	if b != 1 {
+		t.Errorf("actual: %d", b)
+	}
+	b = f.PlainOffToBlockNo(788)
+	if b != 0 {
+		t.Errorf("actual: %d", b)
+	}
+	b = f.PlainOffToBlockNo(f.plainBS)
+	if b != 1 {
+		t.Errorf("actual: %d", b)
+	}
+}