rdisc: obey rtr_solicitations and rtr_solicitation_interval

The IPv6 spec say that when performing SLAAC, you should sent at most
3 RSes, at least 4 seconds apart. We were previously continuing to
send RSes forever if we didn't get back a response. Fix that.

(Since the fix involves making nm-lndp-rdisc use NMPlatform, it was
necessary to rewrite the rdisc test program a bit, to not try to
include <net/if.h>, which is incompatible with <linux/if.h>.)

src/devices/nm-device.c

@@ -445,13 +445,6 @@ restore_ip6_properties (NMDevice *self)
 		nm_device_ipv6_sysctl_set (self, key, value);
 }
 
-static gint32
-sysctl_get_ipv6_max_addresses (NMDevice *self)
-{
-	return nm_platform_sysctl_get_int32 (ip6_property_path (self, "max_addresses"), 16);
-}
-
-
 /*
  * Get driver info from SIOCETHTOOL ioctl() for 'iface'
  * Returns driver and firmware versions to 'driver_version and' 'firmware_version'
@@ -3498,8 +3491,7 @@ addrconf6_start (NMDevice *self, NMSettingIP6ConfigPrivacy use_tempaddr)
 		priv->ac_ip6_config = NULL;
 	}
 
-	priv->rdisc = nm_lndp_rdisc_new (nm_device_get_ip_ifindex (self), ip_iface,
-	                                 sysctl_get_ipv6_max_addresses (self));
+	priv->rdisc = nm_lndp_rdisc_new (nm_device_get_ip_ifindex (self), ip_iface);
 	if (!priv->rdisc) {
 		nm_log_err (LOGD_IP6, "(%s): failed to start router discovery.", ip_iface);
 		return FALSE;

src/rdisc/nm-fake-rdisc.c

@@ -36,15 +36,15 @@ G_DEFINE_TYPE (NMFakeRDisc, nm_fake_rdisc, NM_TYPE_RDISC)
 /******************************************************************/
 
 NMRDisc *
-nm_fake_rdisc_new (int ifindex, const char *ifname, gint32 max_addresses)
+nm_fake_rdisc_new (int ifindex, const char *ifname)
 {
 	NMRDisc *rdisc = g_object_new (NM_TYPE_FAKE_RDISC, NULL);
 
-	g_assert (rdisc);
-
 	rdisc->ifindex = ifindex;
 	rdisc->ifname = g_strdup (ifname);
-	rdisc->max_addresses = max_addresses;
+	rdisc->max_addresses = NM_RDISC_MAX_ADDRESSES_DEFAULT;
+	rdisc->rtr_solicitations = NM_RDISC_RTR_SOLICITATIONS_DEFAULT;
+	rdisc->rtr_solicitation_interval = NM_RDISC_RTR_SOLICITATION_INTERVAL_DEFAULT;
 
 	return rdisc;
 }

src/rdisc/nm-fake-rdisc.h

@@ -44,6 +44,6 @@ typedef struct {
 
 GType nm_fake_rdisc_get_type (void);
 
-NMRDisc *nm_fake_rdisc_new (int ifindex, const char *ifname, gint32 max_addressses);
+NMRDisc *nm_fake_rdisc_new (int ifindex, const char *ifname);
 
 #endif /* NM_FAKE_RDISC_H */

src/rdisc/nm-lndp-rdisc.c

@@ -40,6 +40,8 @@ typedef struct {
 	GIOChannel *event_channel;
 	guint event_id;
 	guint timeout_id;
+
+	int solicitations_left;
 } NMLNDPRDiscPrivate;
 
 #define NM_LNDP_RDISC_GET_PRIVATE(o) (G_TYPE_INSTANCE_GET_PRIVATE ((o), NM_TYPE_LNDP_RDISC, NMLNDPRDiscPrivate))
@@ -48,19 +50,30 @@ G_DEFINE_TYPE (NMLNDPRDisc, nm_lndp_rdisc, NM_TYPE_RDISC)
 
 /******************************************************************/
 
+static inline gint32
+ipv6_sysctl_get (const char *ifname, const char *property, gint32 defval)
+{
+	return nm_platform_sysctl_get_int32 (nm_utils_ip6_property_path (ifname, property), defval);
+}
+
 NMRDisc *
-nm_lndp_rdisc_new (int ifindex, const char *ifname, gint32 max_addresses)
+nm_lndp_rdisc_new (int ifindex, const char *ifname)
 {
 	NMRDisc *rdisc;
 	NMLNDPRDiscPrivate *priv;
 	int error;
 
 	rdisc = g_object_new (NM_TYPE_LNDP_RDISC, NULL);
-	g_assert (rdisc);
 
 	rdisc->ifindex = ifindex;
 	rdisc->ifname = g_strdup (ifname);
-	rdisc->max_addresses = max_addresses;
+
+	rdisc->max_addresses = ipv6_sysctl_get (ifname, "max_addresses",
+	                                        NM_RDISC_MAX_ADDRESSES_DEFAULT);
+	rdisc->rtr_solicitations = ipv6_sysctl_get (ifname, "router_solicitations",
+	                                            NM_RDISC_RTR_SOLICITATIONS_DEFAULT);
+	rdisc->rtr_solicitation_interval = ipv6_sysctl_get (ifname, "router_solicitation_interval",
+	                                                    NM_RDISC_RTR_SOLICITATION_INTERVAL_DEFAULT);
 
 	priv = NM_LNDP_RDISC_GET_PRIVATE (rdisc);
 	error = ndp_open (&priv->ndp);
@@ -210,8 +223,6 @@ add_dns_domain (NMRDisc *rdisc, const NMRDiscDNSDomain *new)
 	return TRUE;
 }
 
-#define RETRY 10
-
 static gboolean
 send_rs (NMRDisc *rdisc)
 {
@@ -228,13 +239,23 @@ send_rs (NMRDisc *rdisc)
 	error = ndp_msg_send (priv->ndp, msg);
 	if (error)
 		error ("(%s): cannot send router solicitation: %d.", rdisc->ifname, error);
+	else
+		priv->solicitations_left--;
 
 	ndp_msg_destroy (msg);
 
-	debug ("(%s): scheduling router solicitation retry in %d seconds.", rdisc->ifname, RETRY);
-	priv->send_rs_id = g_timeout_add_seconds (RETRY, (GSourceFunc) send_rs, rdisc);
+	if (priv->solicitations_left > 0) {
+		debug ("(%s): scheduling router solicitation retry in %d seconds.",
+		       rdisc->ifname, rdisc->rtr_solicitation_interval);
+		priv->send_rs_id = g_timeout_add_seconds (rdisc->rtr_solicitation_interval,
+		                                          (GSourceFunc) send_rs, rdisc);
+	} else {
+		debug ("(%s): did not receive a router advertisement after %d solicitations.",
+		       rdisc->ifname, rdisc->rtr_solicitations);
+		priv->send_rs_id = 0;
+	}
 
-	return FALSE;
+	return G_SOURCE_REMOVE;
 }
 
 static void
@@ -245,6 +266,7 @@ solicit (NMRDisc *rdisc)
 	if (!priv->send_rs_id) {
 		debug ("(%s): scheduling router solicitation.", rdisc->ifname);
 		priv->send_rs_id = g_idle_add ((GSourceFunc) send_rs, rdisc);
+		priv->solicitations_left = rdisc->rtr_solicitations;
 	}
 }
 

src/rdisc/nm-lndp-rdisc.h

@@ -44,6 +44,6 @@ typedef struct {
 
 GType nm_lndp_rdisc_get_type (void);
 
-NMRDisc *nm_lndp_rdisc_new (int ifindex, const char *ifname, gint32 max_addresses);
+NMRDisc *nm_lndp_rdisc_new (int ifindex, const char *ifname);
 
 #endif /* NM_LNDP_RDISC_H */

src/rdisc/nm-rdisc.h

@@ -94,6 +94,10 @@ typedef enum {
 	NM_RDISC_CONFIG_HOP_LIMIT                           = 1 << 6,
 } NMRDiscConfigMap;
 
+#define NM_RDISC_MAX_ADDRESSES_DEFAULT 16
+#define NM_RDISC_RTR_SOLICITATIONS_DEFAULT 3
+#define NM_RDISC_RTR_SOLICITATION_INTERVAL_DEFAULT 4
+
 /**
  * NMRDisc:
  * @ifindex: Interface index
@@ -108,6 +112,8 @@ typedef struct {
 	char *ifname;
 	GBytes *lladdr;
 	gint32 max_addresses;
+	gint32 rtr_solicitations;
+	gint32 rtr_solicitation_interval;
 
 	NMRDiscDHCPLevel dhcp_level;
 	GArray *gateways;

src/rdisc/tests/rdisc.c

@@ -1,40 +1,68 @@
+/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
+/* rdisc.c - test program
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Copyright (C) 2013 Red Hat, Inc.
+ */
+
 #include <string.h>
 #include <syslog.h>
-#include <net/if.h>
 
 #include "nm-rdisc.h"
 #include "nm-fake-rdisc.h"
 #include "nm-lndp-rdisc.h"
 #include "nm-logging.h"
 
+#include "nm-fake-platform.h"
+#include "nm-linux-platform.h"
+
 int
 main (int argc, char **argv)
 {
 	GMainLoop *loop;
 	NMRDisc *rdisc;
-	NMRDisc *(*new) (int ifindex, const char *ifname, gint32 max_addresses) = nm_lndp_rdisc_new;
+	NMRDisc *(*new) (int ifindex, const char *ifname);
 	int ifindex = 1;
-	char ifname[IF_NAMESIZE];
+	const char *ifname;
 	char mac[6] = { 0x02, 0xaa, 0xbb, 0xcc, 0xdd, 0xee };
 
-	if_indextoname (ifindex, ifname);
-
 	g_type_init ();
 	loop = g_main_loop_new (NULL, FALSE);
-	nm_logging_setup ("debug", NULL, NULL, NULL);
+	nm_logging_setup ("debug", "ip6", NULL, NULL);
 	openlog (G_LOG_DOMAIN, LOG_CONS | LOG_PERROR, LOG_DAEMON);
 
 	argv++;
-	for (; *argv; argv++) {
-		if (!g_strcmp0 (*argv, "--fake"))
-			new = nm_fake_rdisc_new;
-		else {
-			strncpy (ifname, *argv, IF_NAMESIZE);
-			ifindex = if_nametoindex (ifname);
-		}
+	if (!g_strcmp0 (argv[0], "--fake")) {
+		new = nm_fake_rdisc_new;
+		nm_fake_platform_setup ();
+		argv++;
+	} else {
+		new = nm_lndp_rdisc_new;
+		nm_linux_platform_setup ();
 	}
 
-	rdisc = new (ifindex, ifname, 0);
+	if (argv[0]) {
+		ifname = argv[0];
+		ifindex = nm_platform_link_get_ifindex (ifname);
+	} else {
+		ifindex = 1;
+		ifname = nm_platform_link_get_name (ifindex);
+	}
+
+	rdisc = new (ifindex, ifname);
 	if (!rdisc)
 		return EXIT_FAILURE;