hostapd: Global control interface notifications

This commit implements hostapd global control interface notifications
infrastructure. hostapd global control interface clients issue
ATTACH/DETACH commands to register and deregister with hostapd
correspondingly - the same way as for any other hostapd/wpa_supplicant
control interface.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>

hostapd/ctrl_iface.c

@@ -58,6 +58,7 @@ struct wpa_ctrl_dst {
 
 
 static void hostapd_ctrl_iface_send(struct hostapd_data *hapd, int level,
+				    enum wpa_msg_type type,
 				    const char *buf, size_t len);
 
 
@@ -2229,7 +2230,7 @@ static void hostapd_ctrl_iface_msg_cb(void *ctx, int level,
 	struct hostapd_data *hapd = ctx;
 	if (hapd == NULL)
 		return;
-	hostapd_ctrl_iface_send(hapd, level, txt, len);
+	hostapd_ctrl_iface_send(hapd, level, type, txt, len);
 }
 
 
@@ -2452,6 +2453,58 @@ static int hostapd_ctrl_iface_remove(struct hapd_interfaces *interfaces,
 }
 
 
+static int hostapd_global_ctrl_iface_attach(struct hapd_interfaces *interfaces,
+					    struct sockaddr_un *from,
+					    socklen_t fromlen)
+{
+	struct wpa_ctrl_dst *dst;
+
+	dst = os_zalloc(sizeof(*dst));
+	if (dst == NULL)
+		return -1;
+	os_memcpy(&dst->addr, from, sizeof(struct sockaddr_un));
+	dst->addrlen = fromlen;
+	dst->debug_level = MSG_INFO;
+	dst->next = interfaces->global_ctrl_dst;
+	interfaces->global_ctrl_dst = dst;
+	wpa_hexdump(MSG_DEBUG, "CTRL_IFACE monitor attached (global)",
+		    from->sun_path,
+		    fromlen - offsetof(struct sockaddr_un, sun_path));
+	return 0;
+}
+
+
+static int hostapd_global_ctrl_iface_detach(struct hapd_interfaces *interfaces,
+					    struct sockaddr_un *from,
+					    socklen_t fromlen)
+{
+	struct wpa_ctrl_dst *dst, *prev = NULL;
+
+	dst = interfaces->global_ctrl_dst;
+	while (dst) {
+		if (fromlen == dst->addrlen &&
+		    os_memcmp(from->sun_path, dst->addr.sun_path,
+			      fromlen - offsetof(struct sockaddr_un, sun_path))
+		    == 0) {
+			wpa_hexdump(MSG_DEBUG,
+				    "CTRL_IFACE monitor detached (global)",
+				    from->sun_path,
+				    fromlen -
+				    offsetof(struct sockaddr_un, sun_path));
+			if (prev == NULL)
+				interfaces->global_ctrl_dst = dst->next;
+			else
+				prev->next = dst->next;
+			os_free(dst);
+			return 0;
+		}
+		prev = dst;
+		dst = dst->next;
+	}
+	return -1;
+}
+
+
 static void hostapd_ctrl_iface_flush(struct hapd_interfaces *interfaces)
 {
 #ifdef CONFIG_WPS_TESTING
@@ -2470,8 +2523,9 @@ static void hostapd_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 	int res;
 	struct sockaddr_un from;
 	socklen_t fromlen = sizeof(from);
-	char reply[24];
+	char *reply;
 	int reply_len;
+	const int reply_size = 4096;
 
 	res = recvfrom(sock, buf, sizeof(buf) - 1, 0,
 		       (struct sockaddr *) &from, &fromlen);
@@ -2483,6 +2537,16 @@ static void hostapd_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 	buf[res] = '\0';
 	wpa_printf(MSG_DEBUG, "Global ctrl_iface command: %s", buf);
 
+	reply = os_malloc(reply_size);
+	if (reply == NULL) {
+		if (sendto(sock, "FAIL\n", 5, 0, (struct sockaddr *) &from,
+			   fromlen) < 0) {
+			wpa_printf(MSG_DEBUG, "CTRL: sendto failed: %s",
+				   strerror(errno));
+		}
+		return;
+	}
+
 	os_memcpy(reply, "OK\n", 3);
 	reply_len = 3;
 
@@ -2500,6 +2564,14 @@ static void hostapd_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 	} else if (os_strncmp(buf, "REMOVE ", 7) == 0) {
 		if (hostapd_ctrl_iface_remove(interfaces, buf + 7) < 0)
 			reply_len = -1;
+	} else if (os_strcmp(buf, "ATTACH") == 0) {
+		if (hostapd_global_ctrl_iface_attach(interfaces, &from,
+						     fromlen))
+			reply_len = -1;
+	} else if (os_strcmp(buf, "DETACH") == 0) {
+		if (hostapd_global_ctrl_iface_detach(interfaces, &from,
+			fromlen))
+			reply_len = -1;
 #ifdef CONFIG_MODULE_TESTS
 	} else if (os_strcmp(buf, "MODULE_TESTS") == 0) {
 		int hapd_module_tests(void);
@@ -2522,6 +2594,7 @@ static void hostapd_global_ctrl_iface_receive(int sock, void *eloop_ctx,
 		wpa_printf(MSG_DEBUG, "CTRL: sendto failed: %s",
 			   strerror(errno));
 	}
+	os_free(reply);
 }
 
 
@@ -2659,6 +2732,7 @@ fail:
 void hostapd_global_ctrl_iface_deinit(struct hapd_interfaces *interfaces)
 {
 	char *fname = NULL;
+	struct wpa_ctrl_dst *dst, *prev;
 
 	if (interfaces->global_ctrl_sock > -1) {
 		eloop_unregister_read_sock(interfaces->global_ctrl_sock);
@@ -2683,13 +2757,23 @@ void hostapd_global_ctrl_iface_deinit(struct hapd_interfaces *interfaces)
 					   strerror(errno));
 			}
 		}
+	}
+
 	os_free(interfaces->global_iface_path);
 	interfaces->global_iface_path = NULL;
+
+	dst = interfaces->global_ctrl_dst;
+	interfaces->global_ctrl_dst = NULL;
+	while (dst) {
+		prev = dst;
+		dst = dst->next;
+		os_free(prev);
 	}
 }
 
 
 static void hostapd_ctrl_iface_send(struct hostapd_data *hapd, int level,
+				    enum wpa_msg_type type,
 				    const char *buf, size_t len)
 {
 	struct wpa_ctrl_dst *dst, *next;
@@ -2697,9 +2781,17 @@ static void hostapd_ctrl_iface_send(struct hostapd_data *hapd, int level,
 	int idx;
 	struct iovec io[2];
 	char levelstr[10];
+	int s;
 
+	if (type != WPA_MSG_ONLY_GLOBAL) {
+		s = hapd->ctrl_sock;
 		dst = hapd->ctrl_dst;
-	if (hapd->ctrl_sock < 0 || dst == NULL)
+	} else {
+		s = hapd->iface->interfaces->global_ctrl_sock;
+		dst = hapd->iface->interfaces->global_ctrl_dst;
+	}
+
+	if (s < 0 || dst == NULL)
 		return;
 
 	os_snprintf(levelstr, sizeof(levelstr), "<%d>", level);
@@ -2720,16 +2812,22 @@ static void hostapd_ctrl_iface_send(struct hostapd_data *hapd, int level,
 				    offsetof(struct sockaddr_un, sun_path));
 			msg.msg_name = &dst->addr;
 			msg.msg_namelen = dst->addrlen;
-			if (sendmsg(hapd->ctrl_sock, &msg, 0) < 0) {
+			if (sendmsg(s, &msg, 0) < 0) {
 				int _errno = errno;
 				wpa_printf(MSG_INFO, "CTRL_IFACE monitor[%d]: "
 					   "%d - %s",
 					   idx, errno, strerror(errno));
 				dst->errors++;
 				if (dst->errors > 10 || _errno == ENOENT) {
+					if (type != WPA_MSG_ONLY_GLOBAL)
 						hostapd_ctrl_iface_detach(
 							hapd, &dst->addr,
 							dst->addrlen);
+					else
+						hostapd_global_ctrl_iface_detach(
+							hapd->iface->interfaces,
+							&dst->addr,
+							dst->addrlen);
 				}
 			} else
 				dst->errors = 0;

hostapd/main.c

@@ -561,6 +561,7 @@ int main(int argc, char *argv[])
 	interfaces.global_iface_path = NULL;
 	interfaces.global_iface_name = NULL;
 	interfaces.global_ctrl_sock = -1;
+	interfaces.global_ctrl_dst = NULL;
 
 	for (;;) {
 		c = getopt(argc, argv, "b:Bde:f:hKP:Ttu:vg:G:");

src/ap/hostapd.h

@@ -41,6 +41,7 @@ struct hapd_interfaces {
 
 	size_t count;
 	int global_ctrl_sock;
+	struct wpa_ctrl_dst *global_ctrl_dst;
 	char *global_iface_path;
 	char *global_iface_name;
 #ifndef CONFIG_NATIVE_WINDOWS

src/utils/wpa_debug.c

@@ -749,6 +749,33 @@ void wpa_msg_no_global(void *ctx, int level, const char *fmt, ...)
 	bin_clear_free(buf, buflen);
 }
 
+
+void wpa_msg_global_only(void *ctx, int level, const char *fmt, ...)
+{
+	va_list ap;
+	char *buf;
+	int buflen;
+	int len;
+
+	va_start(ap, fmt);
+	buflen = vsnprintf(NULL, 0, fmt, ap) + 1;
+	va_end(ap);
+
+	buf = os_malloc(buflen);
+	if (buf == NULL) {
+		wpa_printf(MSG_ERROR, "%s: Failed to allocate message buffer",
+			   __func__);
+		return;
+	}
+	va_start(ap, fmt);
+	len = vsnprintf(buf, buflen, fmt, ap);
+	va_end(ap);
+	wpa_printf(level, "%s", buf);
+	if (wpa_msg_cb)
+		wpa_msg_cb(ctx, level, WPA_MSG_ONLY_GLOBAL, buf, len);
+	os_free(buf);
+}
+
 #endif /* CONFIG_NO_WPA_MSG */
 
 

src/utils/wpa_debug.h

@@ -164,6 +164,7 @@ void wpa_hexdump_ascii_key(int level, const char *title, const void *buf,
 #define wpa_msg_global(args...) do { } while (0)
 #define wpa_msg_global_ctrl(args...) do { } while (0)
 #define wpa_msg_no_global(args...) do { } while (0)
+#define wpa_msg_global_only(args...) do { } while (0)
 #define wpa_msg_register_cb(f) do { } while (0)
 #define wpa_msg_register_ifname_cb(f) do { } while (0)
 #else /* CONFIG_NO_WPA_MSG */
@@ -243,10 +244,25 @@ PRINTF_FORMAT(3, 4);
 void wpa_msg_no_global(void *ctx, int level, const char *fmt, ...)
 PRINTF_FORMAT(3, 4);
 
+/**
+ * wpa_msg_global_only - Conditional printf for ctrl_iface monitors
+ * @ctx: Pointer to context data; this is the ctx variable registered
+ *	with struct wpa_driver_ops::init()
+ * @level: priority level (MSG_*) of the message
+ * @fmt: printf format string, followed by optional arguments
+ *
+ * This function is used to print conditional debugging and error messages.
+ * This function is like wpa_msg_global(), but it sends the output only as a
+ * global event.
+ */
+void wpa_msg_global_only(void *ctx, int level, const char *fmt, ...)
+PRINTF_FORMAT(3, 4);
+
 enum wpa_msg_type {
 	WPA_MSG_PER_INTERFACE,
 	WPA_MSG_GLOBAL,
 	WPA_MSG_NO_GLOBAL,
+	WPA_MSG_ONLY_GLOBAL,
 };
 
 typedef void (*wpa_msg_cb_func)(void *ctx, int level, enum wpa_msg_type type,

wpa_supplicant/ctrl_iface_unix.c

@@ -316,13 +316,14 @@ static void wpa_supplicant_ctrl_iface_msg_cb(void *ctx, int level,
 		if (!dl_list_empty(&priv->ctrl_dst)) {
 			wpa_supplicant_ctrl_iface_send(
 				wpa_s,
-				type == WPA_MSG_GLOBAL ? NULL : wpa_s->ifname,
+				type != WPA_MSG_PER_INTERFACE ?
+				NULL : wpa_s->ifname,
 				priv->sock, &priv->ctrl_dst, level, txt, len,
 				NULL, priv);
 		}
 	}
 
-	if (wpa_s->ctrl_iface == NULL)
+	if (type == WPA_MSG_ONLY_GLOBAL || wpa_s->ctrl_iface == NULL)
 		return;
 	wpa_supplicant_ctrl_iface_send(wpa_s, NULL, wpa_s->ctrl_iface->sock,
 				       &wpa_s->ctrl_iface->ctrl_dst,