From 275d314d5706e412c346fe85027b888cf7d99f76 Mon Sep 17 00:00:00 2001 From: Xi Wang Date: Mon, 22 Oct 2012 16:09:46 -0400 Subject: [PATCH] Fix incorrect loop condition in egg_hkdf_perform() This does not cause a change in behavior (as evidenced by tests, at least on linux when built with gcc) but is more correct code, and less likely to be miscompiled. The condition (i < 256) in the following loop is always false since i is of type guchar, which is at most 255. guchar i; ... for (i = 1; i < 256; ++i) { ... } This patch changes i to a larger type gint. Also in the loop we have: gcry_md_write (md2, &i, 1); change it to use gcry_md_putc(). --- egg/egg-hkdf.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/egg/egg-hkdf.c b/egg/egg-hkdf.c index e79b9d4..bc2919a 100644 --- a/egg/egg-hkdf.c +++ b/egg/egg-hkdf.c @@ -39,7 +39,7 @@ egg_hkdf_perform (const gchar *hash_algo, gconstpointer input, gsize n_input, gpointer buffer = NULL; gcry_md_hd_t md1, md2; guint hash_len; - guchar i; + gint i; gint flags, algo; gsize step, n_buffer; guchar *at; @@ -89,7 +89,7 @@ egg_hkdf_perform (const gchar *hash_algo, gconstpointer input, gsize n_input, gcry_md_reset (md2); gcry_md_write (md2, buffer, n_buffer); gcry_md_write (md2, info, n_info); - gcry_md_write (md2, &i, 1); + gcry_md_putc (md2, i); n_buffer = hash_len; memcpy (buffer, gcry_md_read (md2, algo), n_buffer);