Add Encrypt() and Decrypt() functionality

pkg/transcrypt/convert.go

@@ -0,0 +1,87 @@
+package transcrypt
+
+import (
+	"bytes"
+	"encoding/binary"
+	"encoding/hex"
+	"fmt"
+	"reflect"
+	"regexp"
+	"strings"
+
+	"github.com/minio/sio"
+)
+
+var regexEncryptedString = regexp.MustCompile(`\d{2}:[\w\d]{24}:[\w\d]*:[\w\d]*`)
+
+func convertValueToHexString(v reflect.Value) (string, error) {
+	var err error
+	switch v.Kind() {
+	case reflect.Int:
+		buf := make([]byte, 0)
+		bufWriter := bytes.NewBuffer(buf)
+		err = binary.Write(bufWriter, binary.BigEndian, v.Int())
+		if err != nil {
+			return "", err
+		}
+		return hex.EncodeToString(bufWriter.Bytes()), nil
+	default:
+		return hex.EncodeToString([]byte(v.String())), nil
+	}
+}
+
+func convertBytesToValue(d []byte, k reflect.Kind) (reflect.Value, error) {
+	switch k {
+	case reflect.Int:
+		decodedInt := binary.BigEndian.Uint64(d)
+		return reflect.ValueOf(int(decodedInt)), nil
+	default:
+		return reflect.ValueOf(string(d)), nil
+	}
+}
+
+func decodeHexString(key string, data string) ([]byte, reflect.Kind, sio.Config, error) {
+	if data == "" {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("value is empty")
+	}
+
+	if !regexEncryptedString.MatchString(data) {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("value is not valid")
+	}
+
+	var split []string
+	split = strings.Split(data, ":")
+
+	var err error
+	var cipherSuiteBytes []byte
+	if cipherSuiteBytes, err = hex.DecodeString(split[0]); err != nil {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot decode cipersuite: %w", err)
+	}
+
+	var nonce []byte
+	if nonce, err = hex.DecodeString(split[1]); err != nil {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot decode nonce: %w", err)
+	}
+
+	var encryptedBytes []byte
+	if encryptedBytes, err = hex.DecodeString(split[2]); err != nil {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot decode encrypted data: %w", err)
+	}
+
+	var kindBytes []byte
+	if kindBytes, err = hex.DecodeString(split[3]); err != nil {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot decode kindBytes: %w", err)
+	}
+
+	var kind reflect.Kind
+	if kind = getKindForString(string(kindBytes)); kind == reflect.Invalid {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot decode kind: %w", err)
+	}
+
+	var cryptoConfig sio.Config
+	if cryptoConfig, err = createCryptoConfig(key, cipherSuiteBytes, nonce); err != nil {
+		return nil, reflect.Invalid, sio.Config{}, fmt.Errorf("cannot create crypto config: %w", err)
+	}
+
+	return encryptedBytes, kind, cryptoConfig, nil
+}