Do not hardcode key length. Pointed out by jsing@

ok deraadt@

diff --git a/sys/dev/rnd.c b/sys/dev/rnd.c
index 945d947..48ae1af 100644 (file)
--- a/sys/dev/rnd.c
+++ b/sys/dev/rnd.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: rnd.c,v 1.196 2018/02/08 09:27:44 mortimer Exp $      */
+/*     $OpenBSD: rnd.c,v 1.197 2018/02/08 10:01:12 mortimer Exp $      */
 
 /*
  * Copyright (c) 2011 Theo de Raadt.
@@ -661,7 +661,7 @@ arc4random_ctx_new()
 
        chacha_ctx *ctx = malloc(sizeof(chacha_ctx), M_TEMP, M_WAITOK);
        arc4random_buf(keybuf, KEYSZ + IVSZ);
-       chacha_keysetup(ctx, keybuf, 256);
+       chacha_keysetup(ctx, keybuf, KEYSZ * 8);
        chacha_ivsetup(ctx, keybuf + KEYSZ, NULL);
        explicit_bzero(keybuf, sizeof(keybuf));
        return (struct arc4random_ctx *)ctx;