nl80211: Use nla_nest_start/end instead of nla_put_nested

Instead of allocating a new message and then moving that into
the message being built, use nla_nest_start() and put the data
into the message directly.

Signed-hostap: Johannes Berg <johannes.berg@intel.com>

src/drivers/driver_nl80211.c

@@ -3763,7 +3763,6 @@ nl80211_scan_common(struct wpa_driver_nl80211_data *drv, u8 cmd,
 		    struct wpa_driver_scan_params *params)
 {
 	struct nl_msg *msg;
-	int err;
 	size_t i;
 
 	msg = nlmsg_alloc();
@@ -3776,23 +3775,20 @@ nl80211_scan_common(struct wpa_driver_nl80211_data *drv, u8 cmd,
 		goto fail;
 
 	if (params->num_ssids) {
-		struct nl_msg *ssids = nlmsg_alloc();
+		struct nlattr *ssids;
+
+		ssids = nla_nest_start(msg, NL80211_ATTR_SCAN_SSIDS);
 		if (ssids == NULL)
 			goto fail;
 		for (i = 0; i < params->num_ssids; i++) {
 			wpa_hexdump_ascii(MSG_MSGDUMP, "nl80211: Scan SSID",
 					  params->ssids[i].ssid,
 					  params->ssids[i].ssid_len);
-			if (nla_put(ssids, i + 1, params->ssids[i].ssid_len,
-				    params->ssids[i].ssid) < 0) {
-				nlmsg_free(ssids);
+			if (nla_put(msg, i + 1, params->ssids[i].ssid_len,
+				    params->ssids[i].ssid) < 0)
 				goto fail;
-			}
 		}
-		err = nla_put_nested(msg, NL80211_ATTR_SCAN_SSIDS, ssids);
-		nlmsg_free(ssids);
-		if (err < 0)
-			goto fail;
+		nla_nest_end(msg, ssids);
 	}
 
 	if (params->extra_ies) {
@@ -3804,22 +3800,17 @@ nl80211_scan_common(struct wpa_driver_nl80211_data *drv, u8 cmd,
 	}
 
 	if (params->freqs) {
-		struct nl_msg *freqs = nlmsg_alloc();
+		struct nlattr *freqs;
+		freqs = nla_nest_start(msg, NL80211_ATTR_SCAN_FREQUENCIES);
 		if (freqs == NULL)
 			goto fail;
 		for (i = 0; params->freqs[i]; i++) {
 			wpa_printf(MSG_MSGDUMP, "nl80211: Scan frequency %u "
 				   "MHz", params->freqs[i]);
-			if (nla_put_u32(freqs, i + 1, params->freqs[i]) < 0) {
-				nlmsg_free(freqs);
+			if (nla_put_u32(msg, i + 1, params->freqs[i]) < 0)
 				goto fail;
-			}
 		}
-		err = nla_put_nested(msg, NL80211_ATTR_SCAN_FREQUENCIES,
-				     freqs);
-		nlmsg_free(freqs);
-		if (err < 0)
-			goto fail;
+		nla_nest_end(msg, freqs);
 	}
 
 	os_free(drv->filter_ssids);
@@ -3846,7 +3837,7 @@ static int wpa_driver_nl80211_scan(struct i802_bss *bss,
 {
 	struct wpa_driver_nl80211_data *drv = bss->drv;
 	int ret = -1, timeout;
-	struct nl_msg *msg, *rates = NULL;
+	struct nl_msg *msg = NULL;
 
 	wpa_dbg(drv->ctx, MSG_DEBUG, "nl80211: scan request");
 	drv->scan_for_auth = 0;
@@ -3856,9 +3847,11 @@ static int wpa_driver_nl80211_scan(struct i802_bss *bss,
 		return -1;
 
 	if (params->p2p_probe) {
+		struct nlattr *rates;
+
 		wpa_printf(MSG_DEBUG, "nl80211: P2P probe - mask SuppRates");
 
-		rates = nlmsg_alloc();
+		rates = nla_nest_start(msg, NL80211_ATTR_SCAN_SUPP_RATES);
 		if (rates == NULL)
 			goto nla_put_failure;
 
@@ -3868,11 +3861,9 @@ static int wpa_driver_nl80211_scan(struct i802_bss *bss,
 		 * 9, 12, 18, 24, 36, 48, 54 Mbps from non-MCS rates. All 5 GHz
 		 * rates are left enabled.
 		 */
-		NLA_PUT(rates, NL80211_BAND_2GHZ, 8,
+		NLA_PUT(msg, NL80211_BAND_2GHZ, 8,
 			"\x0c\x12\x18\x24\x30\x48\x60\x6c");
-		if (nla_put_nested(msg, NL80211_ATTR_SCAN_SUPP_RATES, rates) <
-		    0)
-			goto nla_put_failure;
+		nla_nest_end(msg, rates);
 
 		NLA_PUT_FLAG(msg, NL80211_ATTR_TX_NO_CCK_RATE);
 	}
@@ -3926,7 +3917,6 @@ static int wpa_driver_nl80211_scan(struct i802_bss *bss,
 
 nla_put_failure:
 	nlmsg_free(msg);
-	nlmsg_free(rates);
 	return ret;
 }
 
@@ -3946,8 +3936,6 @@ static int wpa_driver_nl80211_sched_scan(void *priv,
 	struct wpa_driver_nl80211_data *drv = bss->drv;
 	int ret = -1;
 	struct nl_msg *msg;
-	struct nl_msg *match_set_ssid = NULL, *match_sets = NULL;
-	struct nl_msg *match_set_rssi = NULL;
 	size_t i;
 
 	wpa_dbg(drv->ctx, MSG_DEBUG, "nl80211: sched_scan request");
@@ -3966,46 +3954,42 @@ static int wpa_driver_nl80211_sched_scan(void *priv,
 	if ((drv->num_filter_ssids &&
 	    (int) drv->num_filter_ssids <= drv->capa.max_match_sets) ||
 	    params->filter_rssi) {
-		match_sets = nlmsg_alloc();
+		struct nlattr *match_sets;
+		match_sets = nla_nest_start(msg, NL80211_ATTR_SCHED_SCAN_MATCH);
 		if (match_sets == NULL)
 			goto nla_put_failure;
 
 		for (i = 0; i < drv->num_filter_ssids; i++) {
+			struct nlattr *match_set_ssid;
 			wpa_hexdump_ascii(MSG_MSGDUMP,
 					  "nl80211: Sched scan filter SSID",
 					  drv->filter_ssids[i].ssid,
 					  drv->filter_ssids[i].ssid_len);
 
-			match_set_ssid = nlmsg_alloc();
+			match_set_ssid = nla_nest_start(msg, i + 1);
 			if (match_set_ssid == NULL)
 				goto nla_put_failure;
-			NLA_PUT(match_set_ssid,
-				NL80211_ATTR_SCHED_SCAN_MATCH_SSID,
+			NLA_PUT(msg, NL80211_ATTR_SCHED_SCAN_MATCH_SSID,
 				drv->filter_ssids[i].ssid_len,
 				drv->filter_ssids[i].ssid);
 
-			if (nla_put_nested(match_sets, i + 1, match_set_ssid) <
-			    0)
-				goto nla_put_failure;
+			nla_nest_end(msg, match_sets);
 		}
 
 		if (params->filter_rssi) {
-			match_set_rssi = nlmsg_alloc();
+			struct nlattr *match_set_rssi;
+			match_set_rssi = nla_nest_start(msg, 0);
 			if (match_set_rssi == NULL)
 				goto nla_put_failure;
-			NLA_PUT_U32(match_set_rssi,
-				    NL80211_SCHED_SCAN_MATCH_ATTR_RSSI,
+			NLA_PUT_U32(msg, NL80211_SCHED_SCAN_MATCH_ATTR_RSSI,
 				    params->filter_rssi);
 			wpa_printf(MSG_MSGDUMP,
 				   "nl80211: Sched scan RSSI filter %d dBm",
 				   params->filter_rssi);
-			if (nla_put_nested(match_sets, 0, match_set_rssi) < 0)
-				goto nla_put_failure;
+			nla_nest_end(msg, match_set_rssi);
 		}
 
-		if (nla_put_nested(msg, NL80211_ATTR_SCHED_SCAN_MATCH,
-				   match_sets) < 0)
-			goto nla_put_failure;
+		nla_nest_end(msg, match_sets);
 	}
 
 	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
@@ -4023,9 +4007,6 @@ static int wpa_driver_nl80211_sched_scan(void *priv,
 		   "scan interval %d msec", ret, interval);
 
 nla_put_failure:
-	nlmsg_free(match_set_ssid);
-	nlmsg_free(match_sets);
-	nlmsg_free(match_set_rssi);
 	nlmsg_free(msg);
 	return ret;
 }
@@ -4514,18 +4495,15 @@ static int wpa_driver_nl80211_set_key(const char *ifname, struct i802_bss *bss,
 				    NL80211_KEYTYPE_GROUP);
 		}
 	} else if (addr && is_broadcast_ether_addr(addr)) {
-		struct nl_msg *types;
-		int err;
+		struct nlattr *types;
+
 		wpa_printf(MSG_DEBUG, "   broadcast key");
-		types = nlmsg_alloc();
+
+		types = nla_nest_start(msg, NL80211_ATTR_KEY_DEFAULT_TYPES);
 		if (!types)
 			goto nla_put_failure;
-		NLA_PUT_FLAG(types, NL80211_KEY_DEFAULT_TYPE_MULTICAST);
-		err = nla_put_nested(msg, NL80211_ATTR_KEY_DEFAULT_TYPES,
-				     types);
-		nlmsg_free(types);
-		if (err)
-			goto nla_put_failure;
+		NLA_PUT_FLAG(msg, NL80211_KEY_DEFAULT_TYPE_MULTICAST);
+		nla_nest_end(msg, types);
 	}
 	NLA_PUT_U8(msg, NL80211_ATTR_KEY_IDX, key_idx);
 	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, ifindex);
@@ -4559,29 +4537,21 @@ static int wpa_driver_nl80211_set_key(const char *ifname, struct i802_bss *bss,
 	else
 		NLA_PUT_FLAG(msg, NL80211_ATTR_KEY_DEFAULT);
 	if (addr && is_broadcast_ether_addr(addr)) {
-		struct nl_msg *types;
-		int err;
-		types = nlmsg_alloc();
+		struct nlattr *types;
+
+		types = nla_nest_start(msg, NL80211_ATTR_KEY_DEFAULT_TYPES);
 		if (!types)
 			goto nla_put_failure;
-		NLA_PUT_FLAG(types, NL80211_KEY_DEFAULT_TYPE_MULTICAST);
-		err = nla_put_nested(msg, NL80211_ATTR_KEY_DEFAULT_TYPES,
-				     types);
-		nlmsg_free(types);
-		if (err)
-			goto nla_put_failure;
+		NLA_PUT_FLAG(msg, NL80211_KEY_DEFAULT_TYPE_MULTICAST);
+		nla_nest_end(msg, types);
 	} else if (addr) {
-		struct nl_msg *types;
-		int err;
-		types = nlmsg_alloc();
+		struct nlattr *types;
+
+		types = nla_nest_start(msg, NL80211_ATTR_KEY_DEFAULT_TYPES);
 		if (!types)
 			goto nla_put_failure;
-		NLA_PUT_FLAG(types, NL80211_KEY_DEFAULT_TYPE_UNICAST);
-		err = nla_put_nested(msg, NL80211_ATTR_KEY_DEFAULT_TYPES,
-				     types);
-		nlmsg_free(types);
-		if (err)
-			goto nla_put_failure;
+		NLA_PUT_FLAG(msg, NL80211_KEY_DEFAULT_TYPE_UNICAST);
+		nla_nest_end(msg, types);
 	}
 
 	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
@@ -6053,7 +6023,7 @@ static int wpa_driver_nl80211_sta_add(void *priv,
 {
 	struct i802_bss *bss = priv;
 	struct wpa_driver_nl80211_data *drv = bss->drv;
-	struct nl_msg *msg, *wme = NULL;
+	struct nl_msg *msg;
 	struct nl80211_sta_flag_update upd;
 	int ret = -ENOBUFS;
 
@@ -6120,18 +6090,18 @@ static int wpa_driver_nl80211_sta_add(void *priv,
 	NLA_PUT(msg, NL80211_ATTR_STA_FLAGS2, sizeof(upd), &upd);
 
 	if (params->flags & WPA_STA_WMM) {
-		wme = nlmsg_alloc();
+		struct nlattr *wme = nla_nest_start(msg, NL80211_ATTR_STA_WME);
+
 		if (!wme)
 			goto nla_put_failure;
 
 		wpa_printf(MSG_DEBUG, "  * qosinfo=0x%x", params->qosinfo);
-		NLA_PUT_U8(wme, NL80211_STA_WME_UAPSD_QUEUES,
+		NLA_PUT_U8(msg, NL80211_STA_WME_UAPSD_QUEUES,
 				params->qosinfo & WMM_QOSINFO_STA_AC_MASK);
-		NLA_PUT_U8(wme, NL80211_STA_WME_MAX_SP,
+		NLA_PUT_U8(msg, NL80211_STA_WME_MAX_SP,
 				(params->qosinfo >> WMM_QOSINFO_STA_SP_SHIFT) &
 				WMM_QOSINFO_STA_SP_MASK);
-		if (nla_put_nested(msg, NL80211_ATTR_STA_WME, wme) < 0)
-			goto nla_put_failure;
+		nla_nest_end(msg, wme);
 	}
 
 	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
@@ -6143,7 +6113,6 @@ static int wpa_driver_nl80211_sta_add(void *priv,
 	if (ret == -EEXIST)
 		ret = 0;
  nla_put_failure:
-	nlmsg_free(wme);
 	nlmsg_free(msg);
 	return ret;
 }
@@ -6227,7 +6196,7 @@ static int nl80211_create_iface_once(struct wpa_driver_nl80211_data *drv,
 				     enum nl80211_iftype iftype,
 				     const u8 *addr, int wds)
 {
-	struct nl_msg *msg, *flags = NULL;
+	struct nl_msg *msg;
 	int ifidx;
 	int ret = -ENOBUFS;
 
@@ -6244,20 +6213,15 @@ static int nl80211_create_iface_once(struct wpa_driver_nl80211_data *drv,
 	NLA_PUT_U32(msg, NL80211_ATTR_IFTYPE, iftype);
 
 	if (iftype == NL80211_IFTYPE_MONITOR) {
-		int err;
+		struct nlattr *flags;
 
-		flags = nlmsg_alloc();
+		flags = nla_nest_start(msg, NL80211_ATTR_MNTR_FLAGS);
 		if (!flags)
 			goto nla_put_failure;
 
-		NLA_PUT_FLAG(flags, NL80211_MNTR_FLAG_COOK_FRAMES);
-
-		err = nla_put_nested(msg, NL80211_ATTR_MNTR_FLAGS, flags);
+		NLA_PUT_FLAG(msg, NL80211_MNTR_FLAG_COOK_FRAMES);
 
-		nlmsg_free(flags);
-
-		if (err)
-			goto nla_put_failure;
+		nla_nest_end(msg, flags);
 	} else if (wds) {
 		NLA_PUT_U8(msg, NL80211_ATTR_4ADDR, wds);
 	}
@@ -6877,19 +6841,14 @@ static int wpa_driver_nl80211_sta_set_flags(void *priv, const u8 *addr,
 {
 	struct i802_bss *bss = priv;
 	struct wpa_driver_nl80211_data *drv = bss->drv;
-	struct nl_msg *msg, *flags = NULL;
+	struct nl_msg *msg;
+	struct nlattr *flags;
 	struct nl80211_sta_flag_update upd;
 
 	msg = nlmsg_alloc();
 	if (!msg)
 		return -ENOMEM;
 
-	flags = nlmsg_alloc();
-	if (!flags) {
-		nlmsg_free(msg);
-		return -ENOMEM;
-	}
-
 	nl80211_cmd(drv, msg, 0, NL80211_CMD_SET_STATION);
 
 	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX,
@@ -6900,35 +6859,34 @@ static int wpa_driver_nl80211_sta_set_flags(void *priv, const u8 *addr,
 	 * Backwards compatibility version using NL80211_ATTR_STA_FLAGS. This
 	 * can be removed eventually.
 	 */
+	flags = nla_nest_start(msg, NL80211_ATTR_STA_FLAGS);
+	if (!flags)
+		goto nla_put_failure;
 	if (total_flags & WPA_STA_AUTHORIZED)
-		NLA_PUT_FLAG(flags, NL80211_STA_FLAG_AUTHORIZED);
+		NLA_PUT_FLAG(msg, NL80211_STA_FLAG_AUTHORIZED);
 
 	if (total_flags & WPA_STA_WMM)
-		NLA_PUT_FLAG(flags, NL80211_STA_FLAG_WME);
+		NLA_PUT_FLAG(msg, NL80211_STA_FLAG_WME);
 
 	if (total_flags & WPA_STA_SHORT_PREAMBLE)
-		NLA_PUT_FLAG(flags, NL80211_STA_FLAG_SHORT_PREAMBLE);
+		NLA_PUT_FLAG(msg, NL80211_STA_FLAG_SHORT_PREAMBLE);
 
 	if (total_flags & WPA_STA_MFP)
-		NLA_PUT_FLAG(flags, NL80211_STA_FLAG_MFP);
+		NLA_PUT_FLAG(msg, NL80211_STA_FLAG_MFP);
 
 	if (total_flags & WPA_STA_TDLS_PEER)
-		NLA_PUT_FLAG(flags, NL80211_STA_FLAG_TDLS_PEER);
+		NLA_PUT_FLAG(msg, NL80211_STA_FLAG_TDLS_PEER);
 
-	if (nla_put_nested(msg, NL80211_ATTR_STA_FLAGS, flags))
-		goto nla_put_failure;
+	nla_nest_end(msg, flags);
 
 	os_memset(&upd, 0, sizeof(upd));
 	upd.mask = sta_flags_nl80211(flags_or | ~flags_and);
 	upd.set = sta_flags_nl80211(flags_or);
 	NLA_PUT(msg, NL80211_ATTR_STA_FLAGS2, sizeof(upd), &upd);
 
-	nlmsg_free(flags);
-
 	return send_and_recv_msgs(drv, msg, NULL, NULL);
  nla_put_failure:
 	nlmsg_free(msg);
-	nlmsg_free(flags);
 	return -ENOBUFS;
 }
 
@@ -9001,7 +8959,8 @@ static int nl80211_signal_monitor(void *priv, int threshold, int hysteresis)
 {
 	struct i802_bss *bss = priv;
 	struct wpa_driver_nl80211_data *drv = bss->drv;
-	struct nl_msg *msg, *cqm = NULL;
+	struct nl_msg *msg;
+	struct nlattr *cqm;
 	int ret = -1;
 
 	wpa_printf(MSG_DEBUG, "nl80211: Signal monitor threshold=%d "
@@ -9015,20 +8974,18 @@ static int nl80211_signal_monitor(void *priv, int threshold, int hysteresis)
 
 	NLA_PUT_U32(msg, NL80211_ATTR_IFINDEX, bss->ifindex);
 
-	cqm = nlmsg_alloc();
+	cqm = nla_nest_start(msg, NL80211_ATTR_CQM);
 	if (cqm == NULL)
 		goto nla_put_failure;
 
-	NLA_PUT_U32(cqm, NL80211_ATTR_CQM_RSSI_THOLD, threshold);
-	NLA_PUT_U32(cqm, NL80211_ATTR_CQM_RSSI_HYST, hysteresis);
-	if (nla_put_nested(msg, NL80211_ATTR_CQM, cqm) < 0)
-		goto nla_put_failure;
+	NLA_PUT_U32(msg, NL80211_ATTR_CQM_RSSI_THOLD, threshold);
+	NLA_PUT_U32(msg, NL80211_ATTR_CQM_RSSI_HYST, hysteresis);
+	nla_nest_end(msg, cqm);
 
 	ret = send_and_recv_msgs(drv, msg, NULL, NULL);
 	msg = NULL;
 
 nla_put_failure:
-	nlmsg_free(cqm);
 	nlmsg_free(msg);
 	return ret;
 }