P2P: Allow PSK to be used instead of passphrase for persistent GO

This continues optimizations for use of CPU heavy pbkdf2_sha1() in GO
setup after the earlier commit 30c371e8a54c3b1bece6366ff0666da15d63e45e
by allowing PSK to be used instead of passphrase when creating
persistent group information manually for the GO.

It should be noted that this would not meet the requirements in the P2P
specification (GO shall maintain the passphrase), so this should be used
only when there is no need to allow manual configuration of legacy STAs
using the passphrase.

Signed-hostap: Masashi Honma <masashi.honma@gmail.com>

wpa_supplicant/p2p_supplicant.c

@@ -796,15 +796,28 @@ static void p2p_go_configured(void *ctx, void *data)
 		wpa_printf(MSG_DEBUG, "P2P: Group setup without provisioning");
 		if (wpa_s->global->p2p_group_formation == wpa_s)
 			wpa_s->global->p2p_group_formation = NULL;
-		wpa_msg(wpa_s->parent, MSG_INFO, P2P_EVENT_GROUP_STARTED
-			"%s GO ssid=\"%s\" freq=%d passphrase=\"%s\" "
-			"go_dev_addr=" MACSTR "%s",
-			wpa_s->ifname,
-			wpa_ssid_txt(ssid->ssid, ssid->ssid_len),
-			ssid->frequency,
-			params->passphrase ? params->passphrase : "",
-			MAC2STR(wpa_s->global->p2p_dev_addr),
-			params->persistent_group ? " [PERSISTENT]" : "");
+		if (os_strlen(params->passphrase) > 0) {
+			wpa_msg(wpa_s->parent, MSG_INFO, P2P_EVENT_GROUP_STARTED
+				"%s GO ssid=\"%s\" freq=%d passphrase=\"%s\" "
+				"go_dev_addr=" MACSTR "%s", wpa_s->ifname,
+				wpa_ssid_txt(ssid->ssid, ssid->ssid_len),
+				ssid->frequency, params->passphrase,
+				MAC2STR(wpa_s->global->p2p_dev_addr),
+				params->persistent_group ? " [PERSISTENT]" :
+				"");
+		} else {
+			char psk[65];
+			wpa_snprintf_hex(psk, sizeof(psk), params->psk,
+					 sizeof(params->psk));
+			wpa_msg(wpa_s->parent, MSG_INFO, P2P_EVENT_GROUP_STARTED
+				"%s GO ssid=\"%s\" freq=%d psk=%s "
+				"go_dev_addr=" MACSTR "%s", wpa_s->ifname,
+				wpa_ssid_txt(ssid->ssid, ssid->ssid_len),
+				ssid->frequency, psk,
+				MAC2STR(wpa_s->global->p2p_dev_addr),
+				params->persistent_group ? " [PERSISTENT]" :
+				"");
+		}
 
 		if (params->persistent_group)
 			network_id = wpas_p2p_store_persistent_group(
@@ -874,13 +887,16 @@ static void wpas_start_wps_go(struct wpa_supplicant *wpa_s,
 	ssid->key_mgmt = WPA_KEY_MGMT_PSK;
 	ssid->proto = WPA_PROTO_RSN;
 	ssid->pairwise_cipher = WPA_CIPHER_CCMP;
-	ssid->passphrase = os_strdup(params->passphrase);
-	if (ssid->passphrase == NULL) {
-		wpa_msg(wpa_s, MSG_ERROR, "P2P: Failed to copy passphrase for "
-			"GO");
-		wpa_config_remove_network(wpa_s->conf, ssid->id);
-		return;
-	}
+	if (os_strlen(params->passphrase) > 0) {
+		ssid->passphrase = os_strdup(params->passphrase);
+		if (ssid->passphrase == NULL) {
+			wpa_msg(wpa_s, MSG_ERROR, "P2P: Failed to copy "
+				"passphrase for GO");
+			wpa_config_remove_network(wpa_s->conf, ssid->id);
+			return;
+		}
+	} else
+		ssid->passphrase = NULL;
 	ssid->psk_set = params->psk_set;
 	if (ssid->psk_set)
 		os_memcpy(ssid->psk, params->psk, sizeof(ssid->psk));
@@ -4099,14 +4115,15 @@ int wpas_p2p_group_add_persistent(struct wpa_supplicant *wpa_s,
 	params.psk_set = ssid->psk_set;
 	if (params.psk_set)
 		os_memcpy(params.psk, ssid->psk, sizeof(params.psk));
-	if (ssid->passphrase == NULL ||
-	    os_strlen(ssid->passphrase) >= sizeof(params.passphrase)) {
-		wpa_printf(MSG_DEBUG, "P2P: Invalid passphrase in persistent "
-			   "group");
-		return -1;
+	if (ssid->passphrase) {
+		if (os_strlen(ssid->passphrase) >= sizeof(params.passphrase)) {
+			wpa_printf(MSG_ERROR, "P2P: Invalid passphrase in "
+				   "persistent group");
+			return -1;
+		}
+		os_strlcpy(params.passphrase, ssid->passphrase,
+			   sizeof(params.passphrase));
 	}
-	os_strlcpy(params.passphrase, ssid->passphrase,
-		   sizeof(params.passphrase));
 	os_memcpy(params.ssid, ssid->ssid, ssid->ssid_len);
 	params.ssid_len = ssid->ssid_len;
 	params.persistent_group = 1;