diff --git a/padding/ansi_x923.go b/padding/ansi_x923.go
index 8f60ed8..d1f8a6e 100644
--- a/padding/ansi_x923.go
+++ b/padding/ansi_x923.go
@@ -23,6 +23,7 @@ func (pad ansiX923Padding) Pad(src []byte) []byte {
 	return ret
 }
 
+// Unpad decrypted plaintext, non-constant-time
 func (pad ansiX923Padding) Unpad(src []byte) ([]byte, error) {
 	srcLen := len(src)
 	if srcLen == 0 || srcLen%pad.BlockSize() != 0 {
diff --git a/padding/pkcs7.go b/padding/pkcs7.go
index e52abdc..7702291 100644
--- a/padding/pkcs7.go
+++ b/padding/pkcs7.go
@@ -22,6 +22,7 @@ func (pad pkcs7Padding) Pad(src []byte) []byte {
 	return ret
 }
 
+// Unpad decrypted plaintext, non-constant-time
 func (pad pkcs7Padding) Unpad(src []byte) ([]byte, error) {
 	srcLen := len(src)
 	if srcLen == 0 || srcLen%pad.BlockSize() != 0 {