diff --git a/src/server.c b/src/server.c
index 0dd5d61b..77837072 100644
--- a/src/server.c
+++ b/src/server.c
@@ -610,7 +610,7 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
          *    |  1   | Variable |    2     |      10        |
          *    +------+----------+----------+----------------+
          *
-         *    If ATYP & ONETIMEAUTH_FLAG(0x10) == 1, Authentication (HMAC-SHA1) is enabled.
+         *    If ATYP & ONETIMEAUTH_FLAG(0x10) != 0, Authentication (HMAC-SHA1) is enabled.
          *
          *    The key of HMAC-SHA1 is (IV + KEY) and the input is the whole header.
          *    The output of HMAC-SHA is truncated to 10 bytes (leftmost bits).
diff --git a/src/udprelay.c b/src/udprelay.c
index 62b1ff03..e253a787 100644
--- a/src/udprelay.c
+++ b/src/udprelay.c
@@ -911,7 +911,7 @@ static void server_recv_cb(EV_P_ ev_io *w, int revents)
      * |  1   | Variable |    2     | Variable |     10      |
      * +------+----------+----------+----------+-------------+
      *
-     * If ATYP & ONETIMEAUTH_FLAG(0x10) == 1, Authentication (HMAC-SHA1) is enabled.
+     * If ATYP & ONETIMEAUTH_FLAG(0x10) != 0, Authentication (HMAC-SHA1) is enabled.
      *
      * The key of HMAC-SHA1 is (IV + KEY) and the input is the whole packet.
      * The output of HMAC-SHA is truncated to 10 bytes (leftmost bits).