[NetworkInformation] Support network IP/status events

	Add support for the events in NetworkChanged (linux-only).

3 files changed, 383 insertions, 0 deletions

diff --git a/support/Makefile.am b/support/Makefile.am
index c64bfc827c1..95299f8fa9c 100644
--- a/support/Makefile.am
+++ b/support/Makefile.am
@@ -32,6 +32,8 @@ MPH_UNIX_SOURCE =				\
 	fstab.c					\
 	grp.c					\
 	macros.c				\
+	nl.c					\
+	nl.h					\
 	old-map.c				\
 	old-map.h				\
 	pwd.c					\
diff --git a/support/nl.c b/support/nl.c
new file mode 100644
index 00000000000..e36fe6eb1ab
--- /dev/null
+++ b/support/nl.c
@@ -0,0 +1,369 @@
+#include <config.h>
+#include "nl.h"
+
+#if defined(HAVE_LINUX_NETLINK_H) && defined(HAVE_LINUX_RTNETLINK_H)
+
+#include <errno.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <arpa/inet.h>
+#include <linux/netlink.h>
+#include <linux/rtnetlink.h>
+
+#undef NL_DEBUG
+#define NL_DEBUG_PRINT(...)
+/*
+#define NL_DEBUG 1
+#define NL_DEBUG_PRINT(...) g_message(__VA_ARGS__)
+*/
+
+enum event_type {
+	EVT_NONE = 0,
+#define EVT_NONE 0
+	EVT_AVAILABILITY = 1 << 0,
+#define EVT_AVAILABILITY (1 << 0)
+	EVT_ADDRESS = 1 << 1,
+#define EVT_ADDRESS (1 << 1)
+	EVT_ALL = EVT_AVAILABILITY | EVT_ADDRESS
+#define EVT_ALL (EVT_AVAILABILITY | EVT_ADDRESS)
+};
+
+#ifdef NL_DEBUG
+typedef struct {
+	int value;
+	const char *name;
+} value2name_t;
+
+#define INIT(x) { x, #x }
+#define FIND_NAME(a, b) value_to_name (a, b)
+
+#define FIND_RT_TYPE_NAME(b) FIND_NAME (rt_types, b)
+static value2name_t rt_types [] = {
+	INIT (RTM_NEWROUTE),
+	INIT (RTM_DELROUTE),
+	INIT (RTM_GETROUTE),
+	INIT (RTM_NEWADDR),
+	INIT (RTM_DELADDR),
+	INIT (RTM_GETADDR),
+	INIT (RTM_NEWLINK),
+	INIT (RTM_GETLINK),
+	INIT (RTM_DELLINK),
+	INIT (RTM_NEWNEIGH),
+	INIT (RTM_GETNEIGH),
+	INIT (RTM_DELNEIGH),
+	{0, NULL}
+};
+
+#define FIND_RTM_TYPE_NAME(b) FIND_NAME (rtm_types, b)
+static value2name_t rtm_types [] = {
+	INIT (RTN_UNSPEC),
+	INIT (RTN_UNICAST),
+	INIT (RTN_LOCAL),
+	INIT (RTN_BROADCAST),
+	INIT (RTN_ANYCAST),
+	INIT (RTN_MULTICAST),
+	INIT (RTN_BLACKHOLE),
+	INIT (RTN_UNREACHABLE),
+	INIT (RTN_PROHIBIT),
+	INIT (RTN_THROW),
+	INIT (RTN_NAT),
+	INIT (RTN_XRESOLVE),
+	{0, NULL}
+};
+
+#define FIND_RTM_PROTO_NAME(b) FIND_NAME (rtm_protocols, b)
+static value2name_t rtm_protocols[] = {
+	INIT (RTPROT_UNSPEC),
+	INIT (RTPROT_REDIRECT),
+	INIT (RTPROT_KERNEL),
+	INIT (RTPROT_BOOT),
+	INIT (RTPROT_STATIC),
+	{0, NULL}
+};
+
+#define FIND_RTM_SCOPE_NAME(b) FIND_NAME (rtm_scopes, b)
+static value2name_t rtm_scopes [] = {
+	INIT (RT_SCOPE_UNIVERSE),
+	INIT (RT_SCOPE_SITE),
+	INIT (RT_SCOPE_LINK),
+	INIT (RT_SCOPE_HOST),
+	INIT (RT_SCOPE_NOWHERE),
+	{0, NULL}
+};
+
+#define FIND_RTM_ATTRS_NAME(b) FIND_NAME (rtm_attrs, b)
+static value2name_t rtm_attrs [] = {
+	INIT (RTA_UNSPEC),
+	INIT (RTA_DST),
+	INIT (RTA_SRC),
+	INIT (RTA_IIF),
+	INIT (RTA_OIF),
+	INIT (RTA_GATEWAY),
+	INIT (RTA_PRIORITY),
+	INIT (RTA_PREFSRC),
+	INIT (RTA_METRICS),
+	INIT (RTA_MULTIPATH),
+	INIT (RTA_PROTOINFO),
+	INIT (RTA_FLOW),
+	INIT (RTA_CACHEINFO),
+	INIT (RTA_SESSION),
+	INIT (RTA_MP_ALGO),
+	INIT (RTA_TABLE),
+	{0, NULL}
+};
+
+#define FIND_RT_TABLE_NAME(b) FIND_NAME (rtm_tables, b)
+static value2name_t rtm_tables [] = {
+        INIT (RT_TABLE_UNSPEC),
+	INIT (RT_TABLE_COMPAT),
+	INIT (RT_TABLE_DEFAULT),
+	INIT (RT_TABLE_MAIN),
+	INIT (RT_TABLE_LOCAL),
+	{0,0}
+};
+
+static const char *
+value_to_name (value2name_t *tbl, int value)
+{
+	static char auto_name [16];
+
+	while (tbl->name) {
+		if (tbl->value == value)
+			return tbl->name;
+		tbl++;
+	}
+	snprintf (auto_name, sizeof (auto_name), "#%d", value);
+	return auto_name;
+}
+#endif /* NL_DEBUG */
+
+int
+CreateNLSocket (void)
+{
+	int sock;
+	struct sockaddr_nl sa;
+	int ret;
+	
+	sock = socket (AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+
+	ret = fcntl (sock, F_GETFL, 0);
+#ifdef O_NONBLOCK
+	if (ret != -1) {
+		ret |= O_NONBLOCK;
+		ret = fcntl (sock, F_SETFL, ret);
+		if (ret < 0)
+			return -1;
+	}
+#endif
+
+	memset (&sa, 0, sizeof (sa));
+	if (sock < 0)
+		return -1;
+	sa.nl_family = AF_NETLINK;
+	sa.nl_pid = getpid ();
+	sa.nl_groups = RTMGRP_IPV4_ROUTE | RTMGRP_IPV6_ROUTE | RTMGRP_NOTIFY;
+	/* RTNLGRP_IPV4_IFADDR | RTNLGRP_IPV6_IFADDR
+	 * RTMGRP_LINK */
+
+	if (bind (sock, (struct sockaddr *) &sa, sizeof (sa)) < 0)
+		return -1;
+
+	return sock;
+}
+
+int
+ReadEvents (gpointer sock, gpointer buffer, gint32 count, gint32 size)
+{
+	struct nlmsghdr *nlp;
+	struct rtmsg *rtp;
+	int rtl;
+	struct rtattr *rtap;
+	int result;
+	int s;
+
+	NL_DEBUG_PRINT ("ENTER ReadEvents()");
+	result = EVT_NONE;
+	s = GPOINTER_TO_INT (sock);
+	/* This socket is not found by IO layer, so we do everything here */
+	if (count == 0) {
+		while ((count = recv (s, buffer, size, 0)) == -1 && errno == EINTR);
+		if (count <= 0) {
+			NL_DEBUG_PRINT ("EXIT ReadEvents()");
+			return result;
+		}
+	}
+	for (nlp = (struct nlmsghdr *) buffer; NLMSG_OK (nlp, count); nlp = NLMSG_NEXT (nlp, count)) {
+		int family;
+		int addr_length;
+		int msg_type;
+		int table;
+		int protocol;
+		int scope;
+		int rtm_type;
+		gboolean have_dst;
+		gboolean have_src;
+		gboolean have_pref_src;
+		gboolean have_gw;
+#ifdef AF_INET6
+		char dst [16];
+		char src [16];
+		char pref_src [16];
+		char gw [16];
+#else
+		char dst [4];
+		char src [4];
+		char pref_src [4];
+		char gw [4];
+#endif
+
+		msg_type = nlp->nlmsg_type;
+		NL_DEBUG_PRINT ("TYPE: %d %s", msg_type, FIND_RT_TYPE_NAME (msg_type));
+		if (msg_type != RTM_NEWROUTE && msg_type != RTM_DELROUTE)
+			continue;
+
+		rtp = (struct rtmsg *) NLMSG_DATA (nlp);
+		family = rtp->rtm_family;
+#ifdef AF_INET6
+		addr_length = (family == AF_INET) ? 4 : 16;
+#else
+		addr_length = 4;
+#endif
+		table = rtp->rtm_table;
+		protocol = rtp->rtm_protocol;
+		scope = rtp->rtm_scope;
+		rtm_type = rtp->rtm_type;
+		NL_DEBUG_PRINT ("\tRTMSG table: %d %s", table, FIND_RT_TABLE_NAME (table));
+		if (table != RT_TABLE_MAIN && table != RT_TABLE_LOCAL)
+			continue;
+
+		NL_DEBUG_PRINT ("\tRTMSG protocol: %d %s", protocol, FIND_RTM_PROTO_NAME (protocol));
+		NL_DEBUG_PRINT ("\tRTMSG scope: %d %s", scope, FIND_RTM_SCOPE_NAME (scope));
+		NL_DEBUG_PRINT ("\tRTMSG type: %d %s", rtm_type, FIND_RTM_TYPE_NAME (rtm_type));
+
+		rtap = (struct rtattr *) RTM_RTA (rtp);
+		rtl = RTM_PAYLOAD (nlp);
+		// loop & get every attribute
+		//
+		// 
+		// NEW_ROUTE
+		// 	table = RT_TABLE_LOCAL, Scope = HOST + pref.src == src  + type=LOCAL -> new if addr
+		// 	RT_TABLE_MAIN, Scope = Universe, unicast, gateway exists -> NEW default route
+		// DEL_ROUTE
+		// 	table = RT_TABLE_LOCAL, Scope = HOST, perfsrc = dst  + type=LOCAL -> if addr deleted
+		// 	RT_TABLE_MAIN - DELROUTE + unicast -> event (gw down?)
+		have_dst = have_src = have_pref_src = have_gw = FALSE;
+		for(; RTA_OK (rtap, rtl); rtap = RTA_NEXT(rtap, rtl)) {
+			char *data;
+#ifdef NL_DEBUG
+#ifdef AF_INET6
+			char ip [INET6_ADDRSTRLEN];
+			int ip_length = INET6_ADDRSTRLEN;
+#else
+			char ip [INET_ADDRSTRLEN];
+			int ip_length = INET_ADDRSTRLEN;
+#endif
+#endif
+
+			NL_DEBUG_PRINT ("\tAttribute: %d %d (%s)", rtap->rta_len, rtap->rta_type, FIND_RTM_ATTRS_NAME (rtap->rta_type));
+			data = RTA_DATA (rtap);
+			switch (rtap->rta_type) {
+			case RTA_DST:
+				have_dst = TRUE;
+				memcpy (dst, data, addr_length);
+#ifdef NL_DEBUG
+				*ip = 0;
+				inet_ntop (family, RTA_DATA (rtap), ip, ip_length);
+				NL_DEBUG_PRINT ("\t\tDst: %s", ip);
+#endif
+				break;
+			case RTA_PREFSRC:
+				have_pref_src = TRUE;
+				memcpy (pref_src, data, addr_length);
+#ifdef NL_DEBUG
+				*ip = 0;
+				inet_ntop (family, RTA_DATA (rtap), ip, ip_length);
+				NL_DEBUG_PRINT ("\t\tPref. Src.: %s", ip);
+#endif
+				break;
+			case RTA_SRC:
+				have_src = TRUE;
+				memcpy (src, data, addr_length);
+#ifdef NL_DEBUG
+				*ip = 0;
+				inet_ntop (family, RTA_DATA (rtap), ip, ip_length);
+				NL_DEBUG_PRINT ("\tSrc: %s", ip);
+#endif
+				break;
+			case RTA_GATEWAY:
+				have_gw = TRUE;
+				memcpy (gw, data, addr_length);
+#ifdef NL_DEBUG
+				*ip = 0;
+				inet_ntop (family, RTA_DATA (rtap), ip, ip_length);
+				NL_DEBUG_PRINT ("\t\tGateway: %s", ip);
+#endif
+				break;
+			default:
+				break;
+			}
+		}
+		if (msg_type == RTM_NEWROUTE) {
+			if (table == RT_TABLE_MAIN) {
+				NL_DEBUG_PRINT ("NEWROUTE: Availability changed");
+				result |= EVT_AVAILABILITY;
+			} else if (table == RT_TABLE_LOCAL) {
+				NL_DEBUG_PRINT ("NEWROUTE: new IP");
+				if (have_dst && have_pref_src && memcmp (dst, pref_src, addr_length) == 0)
+					result |= EVT_ADDRESS;
+			}
+		} else if (msg_type == RTM_DELROUTE) {
+			if (table == RT_TABLE_MAIN) {
+				if (rtm_type == RTN_UNICAST && (have_dst || have_pref_src)) {
+					result |= EVT_AVAILABILITY;
+					NL_DEBUG_PRINT ("DELROUTE: Availability changed");
+				}
+			} else if (table == RT_TABLE_LOCAL) {
+				if (have_dst && have_pref_src && memcmp (dst, pref_src, addr_length) == 0) {
+					result |= EVT_ADDRESS;
+					NL_DEBUG_PRINT ("DELROUTE: deleted IP");
+				}
+			}
+		}
+		while ((count = recv (s, buffer, size, 0)) == -1 && errno == EINTR);
+		if (count <= 0) {
+			NL_DEBUG_PRINT ("EXIT ReadEvents() -> %d", result);
+			return result;
+		}
+		nlp = (struct nlmsghdr *) buffer;
+	}
+	NL_DEBUG_PRINT ("EXIT ReadEvents() -> %d", result);
+	return result;
+}
+
+int
+CloseNLSocket (gpointer sock)
+{
+	return close (GPOINTER_TO_INT (sock));
+}
+#else
+int
+GetNLSocket (void)
+{
+	return -1;
+}
+
+int
+ReadEvents (gpointer sock, gpointer buffer, gint32 count, gint32 size)
+{
+	return 0;
+}
+
+int
+CloseNLSocket (gpointer sock)
+{
+	return -1;
+}
+#endif /* linux/netlink.h + linux/rtnetlink.h */
+
diff --git a/support/nl.h b/support/nl.h
new file mode 100644
index 00000000000..4a464266382
--- /dev/null
+++ b/support/nl.h
@@ -0,0 +1,12 @@
+#ifndef NL_H
+#define NL_H
+#include <glib.h>
+
+G_BEGIN_DECLS
+int CreateNLSocket (void);
+int ReadEvents (gpointer sock, gpointer buffer, gint32 count, gint32 size);
+int CloseNLSocket (gpointer sock);
+G_END_DECLS
+
+#endif
+