netconfig: Introduce netconfig module

netconfig module will be responsible for the orchestration
of the network configuration with the IP addresses.

iwd creates one netconfig structure per interface index.
The purpose of this struct is to hold all of the interface
related addressing states such as: assigned dhcp
clients, known addresses, routes, etc.

Makefile.am

@@ -206,6 +206,7 @@ src_iwd_SOURCES = src/main.c linux/nl80211.h src/iwd.h src/missing.h \
 					src/rtnlutil.h src/rtnlutil.c \
 					src/auth-proto.h \
 					src/anqp.h src/anqp.c \
+					src/netconfig.h src/netconfig.c\
 					$(eap_sources) \
 					$(builtin_sources)
 src_iwd_LDADD = $(ell_ldadd) -ldl

src/netconfig.c

@@ -0,0 +1,144 @@
+/*
+ *
+ *  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 <errno.h>
+#include <linux/rtnetlink.h>
+
+#include <ell/ell.h>
+
+#include "src/iwd.h"
+#include "src/netconfig.h"
+
+struct netconfig {
+	uint32_t ifindex;
+};
+
+static struct l_queue *netconfig_list;
+
+static void netconfig_destroy(void *data)
+{
+	struct netconfig *netconfig = data;
+
+	l_free(netconfig);
+}
+
+static bool netconfig_match(const void *a, const void *b)
+{
+	const struct netconfig *netconfig = a;
+	uint32_t ifindex = L_PTR_TO_UINT(b);
+
+	if (netconfig->ifindex == ifindex)
+		return true;
+
+	return false;
+}
+
+static struct netconfig *netconfig_find(uint32_t ifindex)
+{
+	const struct l_queue_entry *entry;
+
+	for (entry = l_queue_get_entries(netconfig_list); entry;
+							entry = entry->next) {
+		struct netconfig *netconfig = entry->data;
+
+		if (netconfig->ifindex != ifindex)
+			continue;
+
+		return netconfig;
+	}
+
+	return NULL;
+}
+
+bool netconfig_ifindex_add(uint32_t ifindex)
+{
+	struct netconfig *netconfig;
+
+	if (!netconfig_list)
+		return false;
+
+	l_debug("Starting netconfig for interface: %d", ifindex);
+
+	netconfig = netconfig_find(ifindex);
+	if (netconfig)
+		return true;
+
+	netconfig = l_new(struct netconfig, 1);
+	netconfig->ifindex = ifindex;
+
+	l_queue_push_tail(netconfig_list, netconfig);
+
+	return true;
+}
+
+bool netconfig_ifindex_remove(uint32_t ifindex)
+{
+	struct netconfig *netconfig;
+
+	if (!netconfig_list)
+		return false;
+
+	l_debug();
+
+	netconfig = l_queue_remove_if(netconfig_list, netconfig_match,
+							L_UINT_TO_PTR(ifindex));
+	if (!netconfig)
+		return false;
+
+	netconfig_destroy(netconfig);
+
+	return true;
+}
+
+static int netconfig_init(void)
+{
+	bool enabled;
+
+	if (netconfig_list)
+		return -EALREADY;
+
+	if (!l_settings_get_bool(iwd_get_config(), "General",
+					"enable_network_config", &enabled) ||
+								!enabled) {
+		l_warn("netconfig: Network configuration with the IP addresses "
+								"is disabled.");
+		return false;
+	}
+
+	netconfig_list = l_queue_new();
+
+	return 0;
+}
+
+static void netconfig_exit(void)
+{
+	if (!netconfig_list)
+		return;
+
+	l_queue_destroy(netconfig_list, netconfig_destroy);
+}
+
+IWD_MODULE(netconfig, netconfig_init, netconfig_exit)

src/netconfig.h

@@ -0,0 +1,24 @@
+/*
+ *
+ *  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
+ *
+ */
+
+bool netconfig_ifindex_add(uint32_t ifindex);
+bool netconfig_ifindex_remove(uint32_t ifindex);