diff --git a/hostapd/ieee802_11.c b/hostapd/ieee802_11.c
index a3bffc77c..bf50abbce 100644
--- a/hostapd/ieee802_11.c
+++ b/hostapd/ieee802_11.c
@@ -639,7 +639,7 @@ static u16 check_assoc_ies(struct hostapd_data *hapd, struct sta_info *sta,
 {
 	struct ieee802_11_elems elems;
 	u16 resp;
-	u8 *wpa_ie;
+	const u8 *wpa_ie;
 	size_t wpa_ie_len;
 
 	if (ieee802_11_parse_elems(ies, ies_len, &elems, 1) == ParseFailed) {
diff --git a/src/common/ieee802_11_common.c b/src/common/ieee802_11_common.c
index 79a9325ed..96ef5b65a 100644
--- a/src/common/ieee802_11_common.c
+++ b/src/common/ieee802_11_common.c
@@ -1,6 +1,6 @@
 /*
  * IEEE 802.11 Common routines
- * Copyright (c) 2002-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -19,7 +19,7 @@
 #include "ieee802_11_common.h"
 
 
-static int ieee802_11_parse_vendor_specific(u8 *pos, size_t elen,
+static int ieee802_11_parse_vendor_specific(const u8 *pos, size_t elen,
 					    struct ieee802_11_elems *elems,
 					    int show_errors)
 {
@@ -131,12 +131,12 @@ static int ieee802_11_parse_vendor_specific(u8 *pos, size_t elen,
  * @show_errors: Whether to show parsing errors in debug log
  * Returns: Parsing result
  */
-ParseRes ieee802_11_parse_elems(u8 *start, size_t len,
+ParseRes ieee802_11_parse_elems(const u8 *start, size_t len,
 				struct ieee802_11_elems *elems,
 				int show_errors)
 {
 	size_t left = len;
-	u8 *pos = start;
+	const u8 *pos = start;
 	int unknown = 0;
 
 	os_memset(elems, 0, sizeof(*elems));
diff --git a/src/common/ieee802_11_common.h b/src/common/ieee802_11_common.h
index 4a48046ff..4a4f5a742 100644
--- a/src/common/ieee802_11_common.h
+++ b/src/common/ieee802_11_common.h
@@ -1,6 +1,6 @@
 /*
  * IEEE 802.11 Common routines
- * Copyright (c) 2002-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -17,57 +17,58 @@
 
 /* Parsed Information Elements */
 struct ieee802_11_elems {
-	u8 *ssid;
+	const u8 *ssid;
+	const u8 *supp_rates;
+	const u8 *fh_params;
+	const u8 *ds_params;
+	const u8 *cf_params;
+	const u8 *tim;
+	const u8 *ibss_params;
+	const u8 *challenge;
+	const u8 *erp_info;
+	const u8 *ext_supp_rates;
+	const u8 *wpa_ie;
+	const u8 *rsn_ie;
+	const u8 *wmm; /* WMM Information or Parameter Element */
+	const u8 *wmm_tspec;
+	const u8 *wps_ie;
+	const u8 *power_cap;
+	const u8 *supp_channels;
+	const u8 *mdie;
+	const u8 *ftie;
+	const u8 *timeout_int;
+	const u8 *ht_capabilities;
+	const u8 *ht_operation;
+	const u8 *vendor_ht_cap;
+
 	u8 ssid_len;
-	u8 *supp_rates;
 	u8 supp_rates_len;
-	u8 *fh_params;
 	u8 fh_params_len;
-	u8 *ds_params;
 	u8 ds_params_len;
-	u8 *cf_params;
 	u8 cf_params_len;
-	u8 *tim;
 	u8 tim_len;
-	u8 *ibss_params;
 	u8 ibss_params_len;
-	u8 *challenge;
 	u8 challenge_len;
-	u8 *erp_info;
 	u8 erp_info_len;
-	u8 *ext_supp_rates;
 	u8 ext_supp_rates_len;
-	u8 *wpa_ie;
 	u8 wpa_ie_len;
-	u8 *rsn_ie;
 	u8 rsn_ie_len;
-	u8 *wmm; /* WMM Information or Parameter Element */
 	u8 wmm_len; /* 7 = WMM Information; 24 = WMM Parameter */
-	u8 *wmm_tspec;
 	u8 wmm_tspec_len;
-	u8 *wps_ie;
 	u8 wps_ie_len;
-	u8 *power_cap;
 	u8 power_cap_len;
-	u8 *supp_channels;
 	u8 supp_channels_len;
-	u8 *mdie;
 	u8 mdie_len;
-	u8 *ftie;
 	u8 ftie_len;
-	u8 *timeout_int;
 	u8 timeout_int_len;
-	u8 *ht_capabilities;
 	u8 ht_capabilities_len;
-	u8 *ht_operation;
 	u8 ht_operation_len;
-	u8 *vendor_ht_cap;
 	u8 vendor_ht_cap_len;
 };
 
 typedef enum { ParseOK = 0, ParseUnknown = 1, ParseFailed = -1 } ParseRes;
 
-ParseRes ieee802_11_parse_elems(u8 *start, size_t len,
+ParseRes ieee802_11_parse_elems(const u8 *start, size_t len,
 				struct ieee802_11_elems *elems,
 				int show_errors);
 int ieee802_11_ie_count(const u8 *ies, size_t ies_len);
diff --git a/wpa_supplicant/mlme.c b/wpa_supplicant/mlme.c
index c71cdd317..cb2dffebe 100644
--- a/wpa_supplicant/mlme.c
+++ b/wpa_supplicant/mlme.c
@@ -130,11 +130,11 @@ static int ecw2cw(int ecw)
 
 
 static void ieee80211_sta_wmm_params(struct wpa_supplicant *wpa_s,
-				     u8 *wmm_param, size_t wmm_param_len)
+				     const u8 *wmm_param, size_t wmm_param_len)
 {
 	size_t left;
 	int count;
-	u8 *pos;
+	const u8 *pos;
 	u8 wmm_acm;
 
 	if (wmm_param_len < 8 || wmm_param[5] /* version */ != 1)
@@ -218,8 +218,8 @@ static int ieee80211_sta_tx(struct wpa_supplicant *wpa_s, const u8 *buf,
 
 
 static void ieee80211_send_auth(struct wpa_supplicant *wpa_s,
-				int transaction, u8 *extra, size_t extra_len,
-				int encrypt)
+				int transaction, const u8 *extra,
+				size_t extra_len, int encrypt)
 {
 	u8 *buf;
 	size_t len;