hostapd: add support for WPS pushbutton station

similar to hostapd, also add a ubus interface for wpa_supplicant
which will allow handling WPS push-button just as it works for hostapd.
In order to have wpa_supplicant running without any network
configuration (so you can use it to retrieve credentials via WPS),
configure wifi-iface in /etc/config/wireless:

  config wifi-iface 'default_radio0'
      option device 'radio0'
      option network 'wwan'
      option mode 'sta'
      option encryption 'wps'

This section will automatically be edited if credentials have
successfully been acquired via WPS.

Size difference (mips_24kc): roughly +4kb for the 'full' variants of
wpa_supplicant and wpad which do support WPS.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>

package/network/services/hostapd/Makefile

@@ -7,7 +7,7 @@
 include $(TOPDIR)/rules.mk
 
 PKG_NAME:=hostapd
-PKG_RELEASE:=6
+PKG_RELEASE:=7
 
 PKG_SOURCE_URL:=http://w1.fi/hostap.git
 PKG_SOURCE_PROTO:=git
@@ -296,7 +296,7 @@ define Package/wpa-supplicant/Default
   CATEGORY:=Network
   TITLE:=WPA Supplicant
   URL:=http://hostap.epitest.fi/wpa_supplicant/
-  DEPENDS:=$(DRV_DEPENDS)
+  DEPENDS:=$(DRV_DEPENDS) +hostapd-common +libubus
   PROVIDES:=wpa-supplicant
   CONFLICTS:=$(SUPPLICANT_PROVIDERS)
   SUPPLICANT_PROVIDERS+=$(1)
@@ -444,10 +444,7 @@ TARGET_CPPFLAGS := \
 	$(if $(CONFIG_WPA_MSG_MIN_PRIORITY),-DCONFIG_MSG_MIN_PRIORITY=$(CONFIG_WPA_MSG_MIN_PRIORITY))
 
 TARGET_CFLAGS += -ffunction-sections -fdata-sections -flto
-TARGET_LDFLAGS += -Wl,--gc-sections -flto=jobserver -fuse-linker-plugin
+TARGET_LDFLAGS += -Wl,--gc-sections -flto=jobserver -fuse-linker-plugin -lubox -lubus
-ifeq ($(findstring supplicant,$(BUILD_VARIANT)),)
-  TARGET_LDFLAGS += -lubox -lubus
-endif
 
 ifdef CONFIG_PACKAGE_kmod-cfg80211
   TARGET_LDFLAGS += -lm -lnl-tiny
@@ -534,8 +531,9 @@ define Install/supplicant
 endef
 
 define Package/hostapd-common/install
-	$(INSTALL_DIR) $(1)/lib/netifd
+	$(INSTALL_DIR) $(1)/lib/netifd $(1)/etc/rc.button
 	$(INSTALL_DATA) ./files/hostapd.sh $(1)/lib/netifd/hostapd.sh
+	$(INSTALL_BIN) ./files/wps-hotplug.sh $(1)/etc/rc.button/wps
 endef
 
 define Package/hostapd/install
@@ -549,9 +547,8 @@ Package/hostapd-wolfssl/install = $(Package/hostapd/install)
 
 ifneq ($(LOCAL_TYPE),supplicant)
   define Package/hostapd-utils/install
-	$(INSTALL_DIR) $(1)/usr/sbin $(1)/etc/rc.button
+	$(INSTALL_DIR) $(1)/usr/sbin
 	$(INSTALL_BIN) $(PKG_BUILD_DIR)/hostapd/hostapd_cli $(1)/usr/sbin/
-	$(INSTALL_BIN) ./files/wps-hotplug.sh $(1)/etc/rc.button/wps
   endef
 endif
 

package/network/services/hostapd/files/hostapd.sh

@@ -762,6 +762,9 @@ wpa_supplicant_add_network() {
 			hostapd_append_wep_key network_data
 			append network_data "wep_tx_keyidx=$wep_keyidx" "$N$T"
 		;;
+		wps)
+			key_mgmt='WPS'
+		;;
 		psk|sae|psk-sae)
 			local passphrase
 
@@ -869,7 +872,10 @@ wpa_supplicant_add_network() {
 		append network_data "mcast_rate=$mc_rate" "$N$T"
 	}
 
-	cat >> "$_config" <<EOF
+	if [ "$key_mgnt" = "WPS" ]; then
+		echo "wps_cred_processing=1" >> "$_config"
+	else
+		cat >> "$_config" <<EOF
 network={
 	$scan_ssid
 	ssid="$ssid"
@@ -877,6 +883,7 @@ network={
 	$network_data
 }
 EOF
+	fi
 	return 0
 }
 

package/network/services/hostapd/files/wpa_supplicant-basic.config

@@ -591,3 +591,8 @@ CONFIG_NO_RANDOM_POOL=y
 # Opportunistic Wireless Encryption (OWE)
 # Experimental implementation of draft-harkins-owe-07.txt
 #CONFIG_OWE=y
+
+# uBus IPC/RPC System
+# Services can connect to the bus and provide methods
+# that can be called by other services or clients.
+CONFIG_UBUS=y

package/network/services/hostapd/files/wpa_supplicant-full.config

@@ -593,3 +593,8 @@ CONFIG_IBSS_RSN=y
 # Opportunistic Wireless Encryption (OWE)
 # Experimental implementation of draft-harkins-owe-07.txt
 #CONFIG_OWE=y
+
+# uBus IPC/RPC System
+# Services can connect to the bus and provide methods
+# that can be called by other services or clients.
+CONFIG_UBUS=y

package/network/services/hostapd/files/wpa_supplicant-mini.config

@@ -593,3 +593,8 @@ CONFIG_NO_RANDOM_POOL=y
 # Opportunistic Wireless Encryption (OWE)
 # Experimental implementation of draft-harkins-owe-07.txt
 #CONFIG_OWE=y
+
+# uBus IPC/RPC System
+# Services can connect to the bus and provide methods
+# that can be called by other services or clients.
+CONFIG_UBUS=y

package/network/services/hostapd/files/wpa_supplicant-p2p.config

@@ -593,3 +593,8 @@ CONFIG_IBSS_RSN=y
 # Opportunistic Wireless Encryption (OWE)
 # Experimental implementation of draft-harkins-owe-07.txt
 #CONFIG_OWE=y
+
+# uBus IPC/RPC System
+# Services can connect to the bus and provide methods
+# that can be called by other services or clients.
+CONFIG_UBUS=y

package/network/services/hostapd/files/wps-hotplug.sh

@@ -1,11 +1,56 @@
 #!/bin/sh
 
-if [ "$ACTION" = "pressed" -a "$BUTTON" = "wps" ]; then
+wps_catch_credentials() {
-	cd /var/run/hostapd
+	local iface ifaces ifc ifname ssid encryption key radio radios
-	for socket in *; do
+	local found=0
-		[ -S "$socket" ] || continue
+
-		hostapd_cli -i "$socket" wps_pbc
+	. /usr/share/libubox/jshn.sh
+	ubus -S -t 30 listen wps_credentials | while read creds; do
+		json_init
+		json_load "$creds"
+		json_select wps_credentials || continue
+		json_get_vars ifname ssid key encryption
+		local ifcname="$ifname"
+		json_init
+		json_load "$(ubus -S call network.wireless status)"
+		json_get_keys radios
+		for radio in $radios; do
+			json_select $radio
+			json_select interfaces
+			json_get_keys ifaces
+			for ifc in $ifaces; do
+				json_select $ifc
+				json_get_vars ifname
+				[ "$ifname" = "$ifcname" ] && {
+					ubus -S call uci set "{\"config\":\"wireless\", \"type\":\"wifi-iface\",		\
+								\"match\": { \"device\": \"$radio\", \"encryption\": \"wps\" },	\
+								\"values\": { \"encryption\": \"$encryption\", 			\
+										\"ssid\": \"$ssid\", 				\
+										\"key\": \"$key\" } }"
+					ubus -S call uci commit '{"config": "wireless"}'
+					ubus -S call uci apply
+				}
+				json_select ..
+			done
+			json_select ..
+			json_select ..
+		done
 	done
+}
+
+if [ "$ACTION" = "pressed" -a "$BUTTON" = "wps" ]; then
+	wps_done=0
+	ubusobjs="$( ubus -S list hostapd.* )"
+	for ubusobj in $ubusobjs; do
+		ubus -S call $ubusobj wps_start && wps_done=1
+	done
+	[ $wps_done = 0 ] || return 0
+	wps_done=0
+	ubusobjs="$( ubus -S list wpa_supplicant.* )"
+	for ubusobj in $ubusobjs; do
+		ubus -S call $ubusobj wps_start && wps_done=1
+	done
+	[ $wps_done = 0 ] || wps_catch_credentials &
 fi
 
 return 0

package/network/services/hostapd/patches/600-ubus_support.patch

@@ -341,3 +341,85 @@
  }
  
  
+--- a/wpa_supplicant/Makefile
++++ b/wpa_supplicant/Makefile
+@@ -189,6 +189,12 @@ ifdef CONFIG_EAPOL_TEST
+ CFLAGS += -Werror -DEAPOL_TEST
+ endif
+ 
++ifdef CONFIG_UBUS
++CFLAGS += -DUBUS_SUPPORT
++OBJS += ubus.o
++LIBS += -lubox -lubus
++endif
++
+ ifdef CONFIG_CODE_COVERAGE
+ CFLAGS += -O0 -fprofile-arcs -ftest-coverage
+ LIBS += -lgcov
+@@ -915,6 +921,9 @@ endif
+ ifdef CONFIG_IEEE80211AX
+ OBJS += ../src/ap/ieee802_11_he.o
+ endif
++ifdef CONFIG_UBUS
++OBJS += ../src/ap/ubus.o
++endif
+ endif
+ ifdef CONFIG_WNM_AP
+ CFLAGS += -DCONFIG_WNM_AP
+--- a/wpa_supplicant/wpa_supplicant.c
++++ b/wpa_supplicant/wpa_supplicant.c
+@@ -5998,6 +5998,8 @@ struct wpa_supplicant * wpa_supplicant_a
+ 	}
+ #endif /* CONFIG_P2P */
+ 
++	wpas_ubus_add_bss(wpa_s);
++
+ 	return wpa_s;
+ }
+ 
+@@ -6024,6 +6026,8 @@ int wpa_supplicant_remove_iface(struct w
+ 	struct wpa_supplicant *parent = wpa_s->parent;
+ #endif /* CONFIG_MESH */
+ 
++	wpas_ubus_free_bss(wpa_s);
++
+ 	/* Remove interface from the global list of interfaces */
+ 	prev = global->ifaces;
+ 	if (prev == wpa_s) {
+--- a/wpa_supplicant/wpa_supplicant_i.h
++++ b/wpa_supplicant/wpa_supplicant_i.h
+@@ -17,6 +17,7 @@
+ #include "wps/wps_defs.h"
+ #include "config_ssid.h"
+ #include "wmm_ac.h"
++#include "ubus.h"
+ 
+ extern const char *const wpa_supplicant_version;
+ extern const char *const wpa_supplicant_license;
+@@ -500,6 +501,7 @@ struct wpa_supplicant {
+ 	unsigned char own_addr[ETH_ALEN];
+ 	unsigned char perm_addr[ETH_ALEN];
+ 	char ifname[100];
++	struct wpas_ubus_bss ubus;
+ #ifdef CONFIG_MATCH_IFACE
+ 	int matched;
+ #endif /* CONFIG_MATCH_IFACE */
+--- a/wpa_supplicant/wps_supplicant.c
++++ b/wpa_supplicant/wps_supplicant.c
+@@ -33,6 +33,7 @@
+ #include "p2p/p2p.h"
+ #include "p2p_supplicant.h"
+ #include "wps_supplicant.h"
++#include "ubus.h"
+ 
+ 
+ #ifndef WPS_PIN_SCAN_IGNORE_SEL_REG
+@@ -388,6 +389,8 @@ static int wpa_supplicant_wps_cred(void
+ 	wpa_hexdump_key(MSG_DEBUG, "WPS: Received Credential attribute",
+ 			cred->cred_attr, cred->cred_attr_len);
+ 
++	wpas_ubus_notify(wpa_s, cred);
++
+ 	if (wpa_s->conf->wps_cred_processing == 1)
+ 		return 0;
+ 

package/network/services/hostapd/src/wpa_supplicant/ubus.c

@@ -0,0 +1,249 @@
+/*
+ * wpa_supplicant / ubus support
+ * Copyright (c) 2018, Daniel Golle <daniel@makrotopia.org>
+ * Copyright (c) 2013, Felix Fietkau <nbd@nbd.name>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+
+#include "utils/includes.h"
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "utils/wpabuf.h"
+#include "common/ieee802_11_defs.h"
+#include "wpa_supplicant_i.h"
+#include "wps_supplicant.h"
+#include "ubus.h"
+
+static struct ubus_context *ctx;
+static struct blob_buf b;
+static int ctx_ref;
+
+static inline struct wpa_supplicant *get_wpas_from_object(struct ubus_object *obj)
+{
+	return container_of(obj, struct wpa_supplicant, ubus.obj);
+}
+
+static void ubus_receive(int sock, void *eloop_ctx, void *sock_ctx)
+{
+	struct ubus_context *ctx = eloop_ctx;
+	ubus_handle_event(ctx);
+}
+
+static void ubus_reconnect_timeout(void *eloop_data, void *user_ctx)
+{
+	if (ubus_reconnect(ctx, NULL)) {
+		eloop_register_timeout(1, 0, ubus_reconnect_timeout, ctx, NULL);
+		return;
+	}
+
+	eloop_register_read_sock(ctx->sock.fd, ubus_receive, ctx, NULL);
+}
+
+static void wpas_ubus_connection_lost(struct ubus_context *ctx)
+{
+	eloop_unregister_read_sock(ctx->sock.fd);
+	eloop_register_timeout(1, 0, ubus_reconnect_timeout, ctx, NULL);
+}
+
+static bool wpas_ubus_init(void)
+{
+	if (ctx)
+		return true;
+
+	ctx = ubus_connect(NULL);
+	if (!ctx)
+		return false;
+
+	ctx->connection_lost = wpas_ubus_connection_lost;
+	eloop_register_read_sock(ctx->sock.fd, ubus_receive, ctx, NULL);
+	return true;
+}
+
+static void wpas_ubus_ref_inc(void)
+{
+	ctx_ref++;
+}
+
+static void wpas_ubus_ref_dec(void)
+{
+	ctx_ref--;
+	if (!ctx)
+		return;
+
+	if (ctx_ref)
+		return;
+
+	eloop_unregister_read_sock(ctx->sock.fd);
+	ubus_free(ctx);
+	ctx = NULL;
+}
+
+static int
+wpas_bss_get_features(struct ubus_context *ctx, struct ubus_object *obj,
+			struct ubus_request_data *req, const char *method,
+			struct blob_attr *msg)
+{
+	struct wpa_supplicant *wpa_s = get_wpas_from_object(obj);
+
+	blob_buf_init(&b, 0);
+	blobmsg_add_u8(&b, "ht_supported", ht_supported(wpa_s->hw.modes));
+	blobmsg_add_u8(&b, "vht_supported", vht_supported(wpa_s->hw.modes));
+	ubus_send_reply(ctx, req, b.head);
+
+	return 0;
+}
+
+#ifdef CONFIG_WPS
+static int
+wpas_bss_wps_start(struct ubus_context *ctx, struct ubus_object *obj,
+			struct ubus_request_data *req, const char *method,
+			struct blob_attr *msg)
+{
+	int rc;
+	struct wpa_supplicant *wpa_s = get_wpas_from_object(obj);
+
+	rc = wpas_wps_start_pbc(wpa_s, NULL, 0);
+
+	if (rc != 0)
+		return UBUS_STATUS_NOT_SUPPORTED;
+
+	return 0;
+}
+
+static int
+wpas_bss_wps_cancel(struct ubus_context *ctx, struct ubus_object *obj,
+			struct ubus_request_data *req, const char *method,
+			struct blob_attr *msg)
+{
+	int rc;
+	struct wpa_supplicant *wpa_s = get_wpas_from_object(obj);
+
+	rc = wpas_wps_cancel(wpa_s);
+
+	if (rc != 0)
+		return UBUS_STATUS_NOT_SUPPORTED;
+
+	return 0;
+}
+#endif
+
+static const struct ubus_method bss_methods[] = {
+#ifdef CONFIG_WPS
+	UBUS_METHOD_NOARG("wps_start", wpas_bss_wps_start),
+	UBUS_METHOD_NOARG("wps_cancel", wpas_bss_wps_cancel),
+#endif
+	UBUS_METHOD_NOARG("get_features", wpas_bss_get_features),
+};
+
+static struct ubus_object_type bss_object_type =
+	UBUS_OBJECT_TYPE("wpas_bss", bss_methods);
+
+void wpas_ubus_add_bss(struct wpa_supplicant *wpa_s)
+{
+	struct ubus_object *obj = &wpa_s->ubus.obj;
+	char *name;
+	int ret;
+
+	if (!wpas_ubus_init())
+		return;
+
+	if (asprintf(&name, "wpa_supplicant.%s", wpa_s->ifname) < 0)
+		return;
+
+	obj->name = name;
+	obj->type = &bss_object_type;
+	obj->methods = bss_object_type.methods;
+	obj->n_methods = bss_object_type.n_methods;
+	ret = ubus_add_object(ctx, obj);
+	wpas_ubus_ref_inc();
+}
+
+void wpas_ubus_free_bss(struct wpa_supplicant *wpa_s)
+{
+	struct ubus_object *obj = &wpa_s->ubus.obj;
+	char *name = (char *) obj->name;
+
+	if (!ctx)
+		return;
+
+	if (obj->id) {
+		ubus_remove_object(ctx, obj);
+		wpas_ubus_ref_dec();
+	}
+
+	free(name);
+}
+
+#ifdef CONFIG_WPS
+void wpas_ubus_notify(struct wpa_supplicant *wpa_s, const struct wps_credential *cred)
+{
+	u16 auth_type;
+	char *ifname, *encryption, *ssid, *key;
+	size_t ifname_len;
+
+	if (!cred)
+		return;
+
+	auth_type = cred->auth_type;
+
+	if (auth_type == (WPS_AUTH_WPAPSK | WPS_AUTH_WPA2PSK))
+		auth_type = WPS_AUTH_WPA2PSK;
+
+	if (auth_type != WPS_AUTH_OPEN &&
+	    auth_type != WPS_AUTH_WPAPSK &&
+	    auth_type != WPS_AUTH_WPA2PSK) {
+		wpa_printf(MSG_DEBUG, "WPS: Ignored credentials for "
+			   "unsupported authentication type 0x%x",
+			   auth_type);
+		return;
+	}
+
+	if (auth_type == WPS_AUTH_WPAPSK || auth_type == WPS_AUTH_WPA2PSK) {
+		if (cred->key_len < 8 || cred->key_len > 2 * PMK_LEN) {
+			wpa_printf(MSG_ERROR, "WPS: Reject PSK credential with "
+				   "invalid Network Key length %lu",
+				   (unsigned long) cred->key_len);
+			return;
+		}
+	}
+
+	blob_buf_init(&b, 0);
+
+	ifname_len = strlen(wpa_s->ifname);
+	ifname = blobmsg_alloc_string_buffer(&b, "ifname", ifname_len + 1);
+	memcpy(ifname, wpa_s->ifname, ifname_len + 1);
+	ifname[ifname_len] = '\0';
+	blobmsg_add_string_buffer(&b);
+
+	switch (auth_type) {
+		case WPS_AUTH_WPA2PSK:
+			encryption = "psk2";
+			break;
+		case WPS_AUTH_WPAPSK:
+			encryption = "psk";
+			break;
+		default:
+			encryption = "none";
+			break;
+	}
+
+	blobmsg_add_string(&b, "encryption", encryption);
+
+	ssid = blobmsg_alloc_string_buffer(&b, "ssid", cred->ssid_len + 1);
+	memcpy(ssid, cred->ssid, cred->ssid_len);
+	ssid[cred->ssid_len] = '\0';
+	blobmsg_add_string_buffer(&b);
+
+	if (cred->key_len > 0) {
+		key = blobmsg_alloc_string_buffer(&b, "key", cred->key_len + 1);
+		memcpy(key, cred->key, cred->key_len);
+		key[cred->key_len] = '\0';
+		blobmsg_add_string_buffer(&b);
+	}
+
+//	ubus_notify(ctx, &wpa_s->ubus.obj, "wps_credentials", b.head, -1);
+	ubus_send_event(ctx, "wps_credentials", b.head);
+}
+#endif /* CONFIG_WPS */

package/network/services/hostapd/src/wpa_supplicant/ubus.h

@@ -0,0 +1,53 @@
+/*
+ * wpa_supplicant / ubus support
+ * Copyright (c) 2018, Daniel Golle <daniel@makrotopia.org>
+ * Copyright (c) 2013, Felix Fietkau <nbd@nbd.name>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ */
+#ifndef __WPAS_UBUS_H
+#define __WPAS_UBUS_H
+
+struct wpa_supplicant;
+#include "wps_supplicant.h"
+
+#ifdef UBUS_SUPPORT
+#include <libubus.h>
+
+struct wpas_ubus_bss {
+	struct ubus_object obj;
+};
+
+void wpas_ubus_add_bss(struct wpa_supplicant *wpa_s);
+void wpas_ubus_free_bss(struct wpa_supplicant *wpa_s);
+
+#ifdef CONFIG_WPS
+void wpas_ubus_notify(struct wpa_supplicant *wpa_s, const struct wps_credential *cred);
+#endif
+
+#else
+struct wpas_ubus_bss {};
+
+static inline void wpas_ubus_add_iface(struct wpa_supplicant *wpa_s)
+{
+}
+
+static inline void wpas_ubus_free_iface(struct wpa_supplicant *wpa_s)
+{
+}
+
+static inline void wpas_ubus_add_bss(struct wpa_supplicant *wpa_s)
+{
+}
+
+static inline void wpas_ubus_free_bss(struct wpa_supplicant *wpa_s)
+{
+}
+
+static inline void wpas_ubus_notify(struct wpa_supplicant *wpa_s, struct wps_credential *cred)
+{
+}
+#endif
+
+#endif