From 6ccf516c58e70fc05b7715921413bee67bdbe612 Mon Sep 17 00:00:00 2001
From: Evan Chen <evanchen@kumoly.io>
Date: Fri, 24 Dec 2021 12:39:02 +0800
Subject: [PATCH] update

---
 util/encode.go | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
 create mode 100644 util/encode.go

diff --git a/util/encode.go b/util/encode.go
new file mode 100644
index 0000000..28f3f87
--- /dev/null
+++ b/util/encode.go
@@ -0,0 +1,33 @@
+package util
+
+import "encoding/base64"
+
+const DEFAULT_KEY = "kumoly.io/kumoly/app/util"
+
+func Decrypt(msg, key string) (string, error) {
+	if key == "" {
+		key = DEFAULT_KEY
+	}
+	deb64, err := base64.URLEncoding.DecodeString(msg)
+	if err != nil {
+		return "", err
+	}
+	dec := xor(deb64, []byte(key))
+	return string(dec), nil
+}
+
+func Encrypt(msg, key string) string {
+	if key == "" {
+		key = DEFAULT_KEY
+	}
+	enc := xor([]byte(msg), []byte(key))
+	return base64.URLEncoding.EncodeToString(enc)
+}
+
+func xor(msg, key []byte) []byte {
+	ret := make([]byte, len(msg))
+	for i := 0; i < len(msg); i++ {
+		ret[i] = msg[i] ^ key[i%len(key)]
+	}
+	return ret
+}