Move cipher suite selection into common helper functions

Signed-hostap: Jouni Malinen <j@w1.fi>

src/ap/wpa_auth_ie.c

@@ -564,12 +564,9 @@ int wpa_validate_wpa_ie(struct wpa_authenticator *wpa_auth,
 	}
 #endif /* CONFIG_IEEE80211R */
 
-	if (ciphers & WPA_CIPHER_CCMP)
-		sm->pairwise = WPA_CIPHER_CCMP;
-	else if (ciphers & WPA_CIPHER_GCMP)
-		sm->pairwise = WPA_CIPHER_GCMP;
-	else
-		sm->pairwise = WPA_CIPHER_TKIP;
+	sm->pairwise = wpa_pick_pairwise_cipher(ciphers, 0);
+	if (sm->pairwise < 0)
+		return WPA_INVALID_PAIRWISE;
 
 	/* TODO: clear WPA/WPA2 state if STA changes from one to another */
 	if (wpa_ie[0] == WLAN_EID_RSN)

src/common/wpa_common.c

@@ -1,6 +1,6 @@
 /*
  * WPA/RSN - Shared functions for supplicant and authenticator
- * Copyright (c) 2002-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
@@ -1214,3 +1214,33 @@ int wpa_cipher_put_suites(u8 *pos, int ciphers)
 
 	return num_suites;
 }
+
+
+int wpa_pick_pairwise_cipher(int ciphers, int none_allowed)
+{
+	if (ciphers & WPA_CIPHER_CCMP)
+		return WPA_CIPHER_CCMP;
+	if (ciphers & WPA_CIPHER_GCMP)
+		return WPA_CIPHER_GCMP;
+	if (ciphers & WPA_CIPHER_TKIP)
+		return WPA_CIPHER_TKIP;
+	if (none_allowed && (ciphers & WPA_CIPHER_NONE))
+		return WPA_CIPHER_NONE;
+	return -1;
+}
+
+
+int wpa_pick_group_cipher(int ciphers)
+{
+	if (ciphers & WPA_CIPHER_CCMP)
+		return WPA_CIPHER_CCMP;
+	if (ciphers & WPA_CIPHER_GCMP)
+		return WPA_CIPHER_GCMP;
+	if (ciphers & WPA_CIPHER_TKIP)
+		return WPA_CIPHER_TKIP;
+	if (ciphers & WPA_CIPHER_WEP104)
+		return WPA_CIPHER_WEP104;
+	if (ciphers & WPA_CIPHER_WEP40)
+		return WPA_CIPHER_WEP40;
+	return -1;
+}

src/common/wpa_common.h

@@ -1,6 +1,6 @@
 /*
  * WPA definitions shared between hostapd and wpa_supplicant
- * Copyright (c) 2002-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2002-2013, Jouni Malinen <j@w1.fi>
  *
  * This software may be distributed under the terms of the BSD license.
  * See README for more details.
@@ -390,5 +390,7 @@ int wpa_cipher_valid_pairwise(int cipher);
 u32 wpa_cipher_to_suite(int proto, int cipher);
 int rsn_cipher_put_suites(u8 *pos, int ciphers);
 int wpa_cipher_put_suites(u8 *pos, int ciphers);
+int wpa_pick_pairwise_cipher(int ciphers, int none_allowed);
+int wpa_pick_group_cipher(int ciphers);
 
 #endif /* WPA_COMMON_H */

src/rsn_supp/peerkey.c

@@ -217,23 +217,17 @@ static int wpa_supplicant_process_smk_m2(
 		return -1;
 	}
 
-	cipher = ie.pairwise_cipher & sm->allowed_pairwise_cipher;
-	if (cipher & WPA_CIPHER_CCMP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using CCMP for PeerKey");
-		cipher = WPA_CIPHER_CCMP;
-	} else if (cipher & WPA_CIPHER_GCMP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using GCMP for PeerKey");
-		cipher = WPA_CIPHER_GCMP;
-	} else if (cipher & WPA_CIPHER_TKIP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using TKIP for PeerKey");
-		cipher = WPA_CIPHER_TKIP;
-	} else {
+	cipher = wpa_pick_pairwise_cipher(ie.pairwise_cipher &
+					  sm->allowed_pairwise_cipher, 0);
+	if (cipher < 0) {
 		wpa_printf(MSG_INFO, "RSN: No acceptable cipher in SMK M2");
 		wpa_supplicant_send_smk_error(sm, src_addr, kde.mac_addr,
 					      STK_MUI_SMK, STK_ERR_CPHR_NS,
 					      ver);
 		return -1;
 	}
+	wpa_printf(MSG_DEBUG, "RSN: Using %s for PeerKey",
+		   wpa_cipher_txt(cipher));
 
 	/* TODO: find existing entry and if found, use that instead of adding
 	 * a new one; how to handle the case where both ends initiate at the
@@ -496,17 +490,9 @@ static int wpa_supplicant_process_smk_m5(struct wpa_sm *sm,
 	peerkey->rsnie_p_len = kde->rsn_ie_len;
 	os_memcpy(peerkey->pnonce, kde->nonce, WPA_NONCE_LEN);
 
-	cipher = ie.pairwise_cipher & sm->allowed_pairwise_cipher;
-	if (cipher & WPA_CIPHER_CCMP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using CCMP for PeerKey");
-		peerkey->cipher = WPA_CIPHER_CCMP;
-	} else if (cipher & WPA_CIPHER_GCMP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using GCMP for PeerKey");
-		peerkey->cipher = WPA_CIPHER_GCMP;
-	} else if (cipher & WPA_CIPHER_TKIP) {
-		wpa_printf(MSG_DEBUG, "RSN: Using TKIP for PeerKey");
-		peerkey->cipher = WPA_CIPHER_TKIP;
-	} else {
+	cipher = wpa_pick_pairwise_cipher(ie.pairwise_cipher &
+					  sm->allowed_pairwise_cipher, 0);
+	if (cipher < 0) {
 		wpa_printf(MSG_INFO, "RSN: SMK Peer STA " MACSTR " selected "
 			   "unacceptable cipher", MAC2STR(kde->mac_addr));
 		wpa_supplicant_send_smk_error(sm, src_addr, kde->mac_addr,
@@ -515,6 +501,9 @@ static int wpa_supplicant_process_smk_m5(struct wpa_sm *sm,
 		/* TODO: abort negotiation */
 		return -1;
 	}
+	wpa_printf(MSG_DEBUG, "RSN: Using %s for PeerKey",
+		   wpa_cipher_txt(cipher));
+	peerkey->cipher = cipher;
 
 	return 0;
 }

wpa_supplicant/ap.c

@@ -466,15 +466,9 @@ int wpa_supplicant_create_ap(struct wpa_supplicant *wpa_s,
 		wpa_s->key_mgmt = WPA_KEY_MGMT_NONE;
 	params.key_mgmt_suite = key_mgmt2driver(wpa_s->key_mgmt);
 
-	if (ssid->pairwise_cipher & WPA_CIPHER_CCMP)
-		wpa_s->pairwise_cipher = WPA_CIPHER_CCMP;
-	else if (ssid->pairwise_cipher & WPA_CIPHER_GCMP)
-		wpa_s->pairwise_cipher = WPA_CIPHER_GCMP;
-	else if (ssid->pairwise_cipher & WPA_CIPHER_TKIP)
-		wpa_s->pairwise_cipher = WPA_CIPHER_TKIP;
-	else if (ssid->pairwise_cipher & WPA_CIPHER_NONE)
-		wpa_s->pairwise_cipher = WPA_CIPHER_NONE;
-	else {
+	wpa_s->pairwise_cipher = wpa_pick_pairwise_cipher(ssid->pairwise_cipher,
+							  1);
+	if (wpa_s->pairwise_cipher < 0) {
 		wpa_printf(MSG_WARNING, "WPA: Failed to select pairwise "
 			   "cipher.");
 		return -1;

wpa_supplicant/wpa_supplicant.c

@@ -1033,45 +1033,24 @@ int wpa_supplicant_set_suites(struct wpa_supplicant *wpa_s,
 	}
 
 	sel = ie.group_cipher & ssid->group_cipher;
-	if (sel & WPA_CIPHER_CCMP) {
-		wpa_s->group_cipher = WPA_CIPHER_CCMP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK CCMP");
-	} else if (sel & WPA_CIPHER_GCMP) {
-		wpa_s->group_cipher = WPA_CIPHER_GCMP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK GCMP");
-	} else if (sel & WPA_CIPHER_TKIP) {
-		wpa_s->group_cipher = WPA_CIPHER_TKIP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK TKIP");
-	} else if (sel & WPA_CIPHER_WEP104) {
-		wpa_s->group_cipher = WPA_CIPHER_WEP104;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK WEP104");
-	} else if (sel & WPA_CIPHER_WEP40) {
-		wpa_s->group_cipher = WPA_CIPHER_WEP40;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK WEP40");
-	} else {
+	wpa_s->group_cipher = wpa_pick_group_cipher(sel);
+	if (wpa_s->group_cipher < 0) {
 		wpa_msg(wpa_s, MSG_WARNING, "WPA: Failed to select group "
 			"cipher");
 		return -1;
 	}
+	wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using GTK %s",
+		wpa_cipher_txt(wpa_s->group_cipher));
 
 	sel = ie.pairwise_cipher & ssid->pairwise_cipher;
-	if (sel & WPA_CIPHER_CCMP) {
-		wpa_s->pairwise_cipher = WPA_CIPHER_CCMP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using PTK CCMP");
-	} else if (sel & WPA_CIPHER_GCMP) {
-		wpa_s->pairwise_cipher = WPA_CIPHER_GCMP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using PTK GCMP");
-	} else if (sel & WPA_CIPHER_TKIP) {
-		wpa_s->pairwise_cipher = WPA_CIPHER_TKIP;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using PTK TKIP");
-	} else if (sel & WPA_CIPHER_NONE) {
-		wpa_s->pairwise_cipher = WPA_CIPHER_NONE;
-		wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using PTK NONE");
-	} else {
+	wpa_s->pairwise_cipher = wpa_pick_pairwise_cipher(sel, 1);
+	if (wpa_s->pairwise_cipher < 0) {
 		wpa_msg(wpa_s, MSG_WARNING, "WPA: Failed to select pairwise "
 			"cipher");
 		return -1;
 	}
+	wpa_dbg(wpa_s, MSG_DEBUG, "WPA: using PTK %s",
+		wpa_cipher_txt(wpa_s->pairwise_cipher));
 
 	sel = ie.key_mgmt & ssid->key_mgmt;
 #ifdef CONFIG_SAE