Method Decrypt

server-source-code/internal/util/encryption.go:100–134

Decrypt decrypts data encrypted with Encrypt.

(encrypted string)

// Decrypt decrypts data encrypted with Encrypt.
func (e *Encryption) Decrypt(encrypted string) (string, error) {
	if encrypted == "" {
		return "", nil
	}
	parts := strings.Split(encrypted, ":")
	if len(parts) != 3 {
		return "", fmt.Errorf("encryption: invalid format")
	}
	iv, err := hex.DecodeString(parts[0])
	if err != nil || len(iv) != ivLength {
		return "", fmt.Errorf("encryption: invalid iv")
	}
	authTag, err := hex.DecodeString(parts[1])
	if err != nil || len(authTag) != authTagLength {
		return "", fmt.Errorf("encryption: invalid auth tag")
	}
	ciphertext, err := hex.DecodeString(parts[2])
	if err != nil {
		return "", err
	}
	block, err := aes.NewCipher(e.key)
	if err != nil {
		return "", err
	}
	aead, err := cipher.NewGCM(block)
	if err != nil {
		return "", err
	}
	combined := append(ciphertext, authTag...)
	plaintext, err := aead.Open(nil, iv, combined, nil)
	if err != nil {
		return "", err
	}
	return string(plaintext), nil
}