Fix potential DoS in Decrypt

titanous · titanous · commit 2499bf1bad23 · 2021-04-22T17:10:02.000-04:00
diff --git a/state.go b/state.go
@@ -62,8 +62,11 @@ func (s *CipherState) Decrypt(out, ad, ciphertext []byte) ([]byte, error) {
 		return nil, ErrMaxNonce
 	}
 	out, err := s.c.Decrypt(out, s.n, ad, ciphertext)
+	if err != nil {
+		return nil, err
+	}
 	s.n++
-	return out, err
+	return out, nil
 }
 
 // Cipher returns the low-level symmetric encryption primitive. It should only

Original file line number	Diff line number	Diff line change
`@@ -62,8 +62,11 @@ func (s *CipherState) Decrypt(out, ad, ciphertext []byte) ([]byte, error) {`
`62`	`62`	`return nil, ErrMaxNonce`
`63`	`63`	`}`
`64`	`64`	`out, err := s.c.Decrypt(out, s.n, ad, ciphertext)`
	`65`	`+ if err != nil {`
	`66`	`+ return nil, err`
	`67`	`+ }`
`65`	`68`	`s.n++`
`66`		`- return out, err`
	`69`	`+ return out, nil`
`67`	`70`	`}`
`68`	`71`
`69`	`72`	`// Cipher returns the low-level symmetric encryption primitive. It should only`