Initial open source release

backend/utils/crypt.go

@@ -0,0 +1,69 @@
+package utils
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"encoding/base64"
+	"io"
+	"strings"
+
+	"github.com/google/uuid"
+	"github.com/phishingclub/phishingclub/errs"
+)
+
+func Encrypt(s string, secret string) (string, error) {
+	block, err := aes.NewCipher([]byte(secret))
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	nonce := make([]byte, gcm.NonceSize())
+	if _, err = io.ReadFull(rand.Reader, nonce); err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	ciphertext := gcm.Seal(nonce, nonce, []byte(s), nil)
+	return base64.URLEncoding.EncodeToString(ciphertext), nil
+}
+
+func Decrypt(s string, secret string) (string, error) {
+	block, err := aes.NewCipher([]byte(secret))
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	gcm, err := cipher.NewGCM(block)
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	data, err := base64.URLEncoding.DecodeString(s)
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	nonceSize := gcm.NonceSize()
+	if len(data) < nonceSize {
+		return "", errs.Wrap(err)
+	}
+
+	nonce, ciphertext := data[:nonceSize], data[nonceSize:]
+	plaintext, err := gcm.Open(nil, nonce, ciphertext, nil)
+	if err != nil {
+		return "", errs.Wrap(err)
+	}
+
+	return string(plaintext), nil
+}
+
+// UUIDToSecret converts a UUIDv4 to a 32 char secret string by
+// removing the '-' between the UUID parts
+func UUIDToSecret(id *uuid.UUID) string {
+	return strings.ReplaceAll(id.String(), "-", "")
+}