manager: Add new file for wiphy/interface management

Add manager.c, a new file where the wiphy and interface creation/removal
will be handled and interface use policies will be implemented.  Since
not all kernel-side nl80211 interfaces are tied to kernel-side netdevs,
netdev.c can't manage all of the interfaces that we will be using, so
the logic is being moved to a common place where all interfaces on a
wiphy will be managed according to the policy, device support for things
like P2P and user enabling/disabling/connecting with P2P which require
interfaces to be dynamically added and removed.

Makefile.am

@@ -202,6 +202,7 @@ src_iwd_SOURCES = src/main.c linux/nl80211.h src/iwd.h src/missing.h \
 					src/nl80211util.h src/nl80211util.c \
 					src/owe.h src/owe.c \
 					src/blacklist.h src/blacklist.c \
+					src/manager.c \
 					$(eap_sources) \
 					$(builtin_sources)
 src_iwd_LDADD = $(ell_ldadd) -ldl

src/iwd.h

@@ -48,3 +48,6 @@ void device_exit(void);
 
 bool station_init(void);
 void station_exit(void);
+
+bool manager_init(struct l_genl_family *in);
+void manager_exit(void);

src/main.c

@@ -161,12 +161,14 @@ static void nl80211_appeared(void *user_data)
 
 	ap_init(nl80211);
 	adhoc_init(nl80211);
+	manager_init(nl80211);
 }
 
 static void nl80211_vanished(void *user_data)
 {
 	l_debug("Lost nl80211 interface");
 
+	manager_exit();
 	ap_exit();
 	adhoc_exit();
 	scan_exit();

src/manager.c

@@ -0,0 +1,150 @@
+/*
+ *
+ *  Wireless daemon for Linux
+ *
+ *  Copyright (C) 2019  Intel Corporation. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Lesser General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Lesser General Public
+ *  License along with this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <linux/if_ether.h>
+#include <fnmatch.h>
+
+#include <ell/ell.h>
+
+#include "linux/nl80211.h"
+
+#include "src/iwd.h"
+#include "src/wiphy.h"
+#include "src/util.h"
+#include "src/common.h"
+
+static struct l_genl_family *nl80211 = NULL;
+
+static void manager_new_wiphy_event(struct l_genl_msg *msg)
+{
+	struct wiphy *wiphy;
+	struct l_genl_attr attr;
+	uint32_t id;
+	const char *name;
+
+	if (!l_genl_attr_init(&attr, msg))
+		return;
+
+	if (!wiphy_parse_id_and_name(&attr, &id, &name))
+		return;
+
+	wiphy = wiphy_find(id);
+	if (wiphy) {
+		wiphy_update_from_genl(wiphy, msg);
+		return;
+	}
+
+	wiphy = wiphy_create(id, name);
+	if (!wiphy)	/* Possibly blacklisted */
+		return;
+
+	wiphy_update_from_genl(wiphy, msg);
+}
+
+static uint32_t manager_parse_wiphy_id(struct l_genl_attr *attr)
+{
+	uint16_t type, len;
+	const void *data;
+
+	while (l_genl_attr_next(attr, &type, &len, &data)) {
+		if (type != NL80211_ATTR_WIPHY)
+			continue;
+
+		if (len != sizeof(uint32_t))
+			break;
+
+		return *((uint32_t *) data);
+	}
+
+	return -1;
+}
+
+static void manager_del_wiphy_event(struct l_genl_msg *msg)
+{
+	struct wiphy *wiphy;
+	struct l_genl_attr attr;
+	uint32_t id;
+
+	if (!l_genl_attr_init(&attr, msg))
+		return;
+
+	id = manager_parse_wiphy_id(&attr);
+
+	wiphy = wiphy_find(id);
+	if (wiphy)
+		wiphy_destroy(wiphy);
+}
+
+static void manager_config_notify(struct l_genl_msg *msg, void *user_data)
+{
+	uint8_t cmd;
+
+	cmd = l_genl_msg_get_command(msg);
+
+	l_debug("Notification of command %u", cmd);
+
+	switch (cmd) {
+	case NL80211_CMD_NEW_WIPHY:
+		manager_new_wiphy_event(msg);
+		break;
+
+	case NL80211_CMD_DEL_WIPHY:
+		manager_del_wiphy_event(msg);
+		break;
+	}
+}
+
+static void manager_wiphy_dump_callback(struct l_genl_msg *msg, void *user_data)
+{
+	l_debug("");
+
+	manager_new_wiphy_event(msg);
+}
+
+bool manager_init(struct l_genl_family *in)
+{
+	nl80211 = in;
+
+	if (!l_genl_family_register(nl80211, "config", manager_config_notify,
+					NULL, NULL))
+		l_error("Registering for config notifications failed");
+
+	if (!l_genl_family_dump(nl80211,
+				l_genl_msg_new(NL80211_CMD_GET_WIPHY),
+				manager_wiphy_dump_callback,
+				NULL, NULL))
+		l_error("Initial wiphy information dump failed");
+
+	return true;
+}
+
+void manager_exit(void)
+{
+	nl80211 = NULL;
+}