f

go.work

@@ -2,5 +2,5 @@ go 1.23.0
 
 use (
 	./
-
+	./pkg/crypto
 )

pkg/crypto/go.mod

@@ -0,0 +1,3 @@
+module github.com/zeevdiukman/z/crypto
+
+go 1.23.0

pkg/crypto/sketch.go

@@ -0,0 +1,63 @@
+package sketch
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+)
+
+func Encrypt(plaintext string, key []byte) (string, error) {
+	// Create a new AES cipher
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return "", err
+	}
+
+	// Generate a random nonce
+	nonce := make([]byte, 12)
+	if _, err := rand.Read(nonce); err != nil {
+		return "", err
+	}
+
+	// Create a GCM cipher
+	gcm, err := cipher.NewGCM(c)
+	if err != nil {
+		return "", err
+	}
+
+	// Encrypt the plaintext
+	ciphertext := gcm.Seal(nonce, nonce, []byte(plaintext), nil)
+
+	// Encode the ciphertext to base64
+	return base64.StdEncoding.EncodeToString(ciphertext), nil
+}
+
+func Decrypt(ciphertext string, key []byte) (string, error) {
+	// Decode the ciphertext from base64
+	ciphertextBytes, err := base64.StdEncoding.DecodeString(ciphertext)
+	if err != nil {
+		return "", err
+	}
+
+	// Create a new AES cipher
+	c, err := aes.NewCipher(key)
+	if err != nil {
+		return "", err
+	}
+
+	// Create a GCM cipher
+	gcm, err := cipher.NewGCM(c)
+	if err != nil {
+		return "", err
+	}
+
+	// Decrypt the ciphertext
+	nonce := ciphertextBytes[:12]
+	plaintext, err := gcm.Open(nil, nonce, ciphertextBytes[12:], nil)
+	if err != nil {
+		return "", err
+	}
+
+	return string(plaintext), nil
+}