support encrypted database

interface.go

@@ -5,6 +5,7 @@ type Manager interface {
 	// If the vault does not exist, it will be created.
 	// If id is empty, DefaultVaultID will be used.
 	OpenVault(id string) (Vault, error)
+	OpenVaultCrypto(id string, cryptoKey string) (Vault, error)
 }
 
 type Vault interface {

manager.go

@@ -42,7 +42,7 @@ func (m *manager) OpenVault(id string) (Vault, error) {
 		return v, nil
 	}
 
-	vault, err := m.openVault(id)
+	vault, err := m.openVault(id, "")
 	if err != nil {
 		return nil, fmt.Errorf("failed to open vault: %w", err)
 	}
@@ -51,7 +51,25 @@ func (m *manager) OpenVault(id string) (Vault, error) {
 	return vault, nil
 }
 
-func (m *manager) openVault(id string) (Vault, error) {
+func (m *manager) OpenVaultCrypto(id string, cryptoKey string) (Vault, error) {
+	if id == "" {
+		id = DefaultVaultID
+	}
+
+	if v, ok := m.vaults[id]; ok {
+		return v, nil
+	}
+
+	vault, err := m.openVault(id, cryptoKey)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open vault: %w", err)
+	}
+	m.vaults[id] = vault
+
+	return vault, nil
+}
+
+func (m *manager) openVault(id string, cryptoKey string) (Vault, error) {
 	metaFile, err := os.Open(path.Join(m.dir, id+".crc"))
 	if err != nil {
 		return nil, fmt.Errorf("failed to open metadata file: %w", err)
@@ -69,7 +87,7 @@ func (m *manager) openVault(id string) (Vault, error) {
 		return nil, fmt.Errorf("failed to load metadata: %w", err)
 	}
 
-	v, err := loadVault(vaultFile, meta)
+	v, err := loadVault(vaultFile, meta, cryptoKey)
 	if err != nil {
 		return nil, fmt.Errorf("failed to load vault: %w", err)
 	}

manager_test.go

@@ -7,11 +7,28 @@ import (
 )
 
 func TestNewManager(t *testing.T) {
-	mgr, err := NewManager("./testdata")
-	assert.NoError(t, err)
-	assert.NotNil(t, mgr)
+	t.Run("Default", func(t *testing.T) {
+		mgr, err := NewManager("./testdata")
+		assert.NoError(t, err)
+		assert.NotNil(t, mgr)
 
-	vault, err := mgr.OpenVault("")
-	assert.NoError(t, err)
-	assert.NotNil(t, vault)
+		vault, err := mgr.OpenVault("")
+		assert.NoError(t, err)
+		assert.NotNil(t, vault)
+	})
+	t.Run("Crypto", func(t *testing.T) {
+		mgr, err := NewManager("./testdata")
+		assert.NoError(t, err)
+		assert.NotNil(t, mgr)
+
+		vault, err := mgr.OpenVaultCrypto("crypto", "123456")
+		val, err := vault.GetString("world")
+		assert.NotNil(t, vault)
+
+		assert.Equal(t, "hello", val)
+		assert.NoError(t, err)
+
+		_, err = vault.GetBytes("foo")
+		assert.Error(t, err)
+	})
 }

vault.go

@@ -1,6 +1,8 @@
 package mmkv
 
 import (
+	"crypto/aes"
+	"crypto/cipher"
 	"encoding/binary"
 	"fmt"
 	"hash/crc32"
@@ -44,8 +46,8 @@ func (v vault) GetString(key string) (string, error) {
 	return string(val), nil
 }
 
-// metadata is optional. but if it exists, validate with it.
-func loadVault(src io.Reader, m *metadata) (Vault, error) {
+// metadata and cryptoKey are optional. but if it exists, validate with them.
+func loadVault(src io.Reader, m *metadata, cryptoKey string) (Vault, error) {
 	fileSizeBuf := make([]byte, 4)
 	_, err := io.ReadFull(src, fileSizeBuf)
 	if err != nil {
@@ -67,6 +69,19 @@ func loadVault(src io.Reader, m *metadata) (Vault, error) {
 		return nil, fmt.Errorf("metadata and vault payload crc32 mismatch")
 	}
 
+	// 将数据库完整解密
+	if len(cryptoKey) > 0 {
+		m_key := make([]byte, aes.BlockSize) // 16 bytes key
+		copy(m_key, cryptoKey)
+
+		block, err := aes.NewCipher(m_key)
+		if err != nil {
+			return nil, fmt.Errorf("failed to create aes cipher")
+		}
+		stream := cipher.NewCFBDecrypter(block, m.aesVector)
+		stream.XORKeyStream(buf, buf)
+	}
+
 	v := make(vault)
 
 	// mmkv is not really protobuf compatible,

vault_test.go

@@ -12,7 +12,7 @@ func Test_loadVault(t *testing.T) {
 	file, err := os.Open("./testdata/mmkv.default")
 	require.NoError(t, err)
 
-	v, err := loadVault(file, nil)
+	v, err := loadVault(file, nil, "")
 	require.NoError(t, err)
 
 	assert.Equal(t, 2, len(v.Keys()))