[#595] Move decrypter to separate package

Signed-off-by: Denis Kirillov <denis@nspcc.ru>

api/layer/encryption/encryption_test.go

@@ -0,0 +1,116 @@
+package encryption
+
+import (
+	"encoding/hex"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+const (
+	aes256Key = "1234567890qwertyuiopasdfghjklzxc"
+)
+
+func getAES256Key() []byte {
+	key := make([]byte, 32)
+	copy(key[:], aes256Key)
+	return key
+}
+
+func TestHMAC(t *testing.T) {
+	encParam, err := NewParams(getAES256Key())
+	require.NoError(t, err)
+
+	hmacKey, hmacSalt, err := encParam.HMAC()
+	require.NoError(t, err)
+
+	encInfo := ObjectEncryption{
+		Enabled:   true,
+		Algorithm: "",
+		HMACKey:   hex.EncodeToString(hmacKey),
+		HMACSalt:  hex.EncodeToString(hmacSalt),
+	}
+
+	err = encParam.MatchObjectEncryption(encInfo)
+	require.NoError(t, err)
+}
+
+const (
+	objSize     = 30 * 1024 * 1024
+	partNum     = 6
+	partSize    = 5 * 1024 * 1024
+	encObjSize  = 31472640 // objSize + enc headers
+	encPartSize = 5245440  // partSize + enc headers
+)
+
+func getDecrypter(t *testing.T) *Decrypter {
+	parts := make([]encryptedPart, partNum)
+	for i := range parts {
+		parts[i] = encryptedPart{
+			size:          partSize,
+			encryptedSize: encPartSize,
+		}
+	}
+
+	params, err := NewParams(getAES256Key())
+	require.NoError(t, err)
+
+	return &Decrypter{
+		parts:      parts,
+		encryption: params,
+	}
+}
+
+func TestDecrypterInitParams(t *testing.T) {
+	decReader := getDecrypter(t)
+
+	for i, tc := range []struct {
+		rng                                       *Range
+		expSkipLen, expLn, expOff, expSeqNumber   uint64
+		expDecLen, expDataRemain, expEncPartRange uint64
+	}{
+		{
+			rng:             &Range{End: objSize - 1},
+			expSkipLen:      0,
+			expLn:           encObjSize,
+			expOff:          0,
+			expSeqNumber:    0,
+			expDecLen:       objSize,
+			expDataRemain:   partSize,
+			expEncPartRange: encPartSize,
+		},
+		{
+			rng:             &Range{End: 999999},
+			expSkipLen:      0,
+			expLn:           1049088,
+			expOff:          0,
+			expSeqNumber:    0,
+			expDecLen:       1000000,
+			expDataRemain:   1000000,
+			expEncPartRange: 1049088,
+		},
+		{
+			rng:             &Range{Start: 1000000, End: 1999999},
+			expSkipLen:      16960,
+			expLn:           1049088,
+			expOff:          983520,
+			expSeqNumber:    15,
+			expDecLen:       1000000,
+			expDataRemain:   1000000,
+			expEncPartRange: 1049088,
+		},
+	} {
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			decReader.rangeParam = tc.rng
+			decReader.initRangeParams()
+			require.Equal(t, tc.expSkipLen, decReader.skipLen)
+			require.Equal(t, tc.expDecLen, decReader.decLen)
+			require.Equal(t, tc.expLn, decReader.ln)
+			require.Equal(t, tc.expOff, decReader.off)
+			require.Equal(t, tc.expDataRemain, decReader.partDataRemain)
+			require.Equal(t, tc.expEncPartRange, decReader.encPartRangeLen)
+			require.Equal(t, tc.expSeqNumber, decReader.seqNumber)
+		})
+	}
+}