net: igmp: fix source address check for IGMPv3 reports

[pandora-kernel.git] / net / ipv4 / igmp.c

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index d9c1d58..96ad44a 100644 (file)
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -89,6 +89,7 @@
 #include <linux/if_arp.h>
 #include <linux/rtnetlink.h>
 #include <linux/times.h>
+#include <linux/byteorder/generic.h>
 
 #include <net/net_namespace.h>
 #include <net/arp.h>
@@ -140,7 +141,7 @@
          time_before(jiffies, (in_dev)->mr_v2_seen)))
 
 static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im);
-static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr);
+static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im);
 static void igmpv3_clear_delrec(struct in_device *in_dev);
 static int sf_setstate(struct ip_mc_list *pmc);
 static void sf_markstate(struct ip_mc_list *pmc);
@@ -197,9 +198,14 @@ static void igmp_start_timer(struct ip_mc_list *im, int max_delay)
 static void igmp_gq_start_timer(struct in_device *in_dev)
 {
        int tv = net_random() % in_dev->mr_maxdelay;
+       unsigned long exp = jiffies + tv + 2;
+
+       if (in_dev->mr_gq_running &&
+           time_after_eq(exp, (in_dev->mr_gq_timer).expires))
+               return;
 
        in_dev->mr_gq_running = 1;
-       if (!mod_timer(&in_dev->mr_gq_timer, jiffies+tv+2))
+       if (!mod_timer(&in_dev->mr_gq_timer, exp))
                in_dev_hold(in_dev);
 }
 
@@ -294,6 +300,23 @@ igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
        return scount;
 }
 
+/* source address selection per RFC 3376 section 4.2.13 */
+static __be32 igmpv3_get_srcaddr(struct net_device *dev,
+                                const struct flowi4 *fl4)
+{
+       struct in_device *in_dev = __in_dev_get_rcu(dev);
+
+       if (!in_dev)
+               return htonl(INADDR_ANY);
+
+       for_ifa(in_dev) {
+               if (fl4->saddr == ifa->ifa_local)
+                       return fl4->saddr;
+       } endfor_ifa(in_dev);
+
+       return htonl(INADDR_ANY);
+}
+
 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 {
        struct sk_buff *skb;
@@ -327,9 +350,8 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
        skb_dst_set(skb, &rt->dst);
        skb->dev = dev;
 
-       skb->reserved_tailroom = skb_end_offset(skb) -
-                                min(mtu, skb_end_offset(skb));
        skb_reserve(skb, hlen);
+       skb_tailroom_reserve(skb, mtu, tlen);
 
        skb_reset_network_header(skb);
        pip = ip_hdr(skb);
@@ -341,7 +363,7 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
        pip->frag_off = htons(IP_DF);
        pip->ttl      = 1;
        pip->daddr    = fl4.daddr;
-       pip->saddr    = fl4.saddr;
+       pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
        pip->protocol = IPPROTO_IGMP;
        pip->tot_len  = 0;      /* filled in later */
        ip_select_ident(skb, NULL);
@@ -1078,10 +1100,14 @@ static void igmpv3_add_delrec(struct in_device *in_dev, struct ip_mc_list *im)
        spin_unlock_bh(&in_dev->mc_tomb_lock);
 }
 
-static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
+/*
+ * restore ip_mc_list deleted records
+ */
+static void igmpv3_del_delrec(struct in_device *in_dev, struct ip_mc_list *im)
 {
        struct ip_mc_list *pmc, *pmc_prev;
-       struct ip_sf_list *psf, *psf_next;
+       struct ip_sf_list *psf;
+       __be32 multiaddr = im->multiaddr;
 
        spin_lock_bh(&in_dev->mc_tomb_lock);
        pmc_prev = NULL;
@@ -1097,16 +1123,27 @@ static void igmpv3_del_delrec(struct in_device *in_dev, __be32 multiaddr)
                        in_dev->mc_tomb = pmc->next;
        }
        spin_unlock_bh(&in_dev->mc_tomb_lock);
+
+       spin_lock_bh(&im->lock);
        if (pmc) {
-               for (psf=pmc->tomb; psf; psf=psf_next) {
-                       psf_next = psf->sf_next;
-                       kfree(psf);
+               im->interface = pmc->interface;
+               im->crcount = in_dev->mr_qrv ?: IGMP_Unsolicited_Report_Count;
+               im->sfmode = pmc->sfmode;
+               if (pmc->sfmode == MCAST_INCLUDE) {
+                       im->tomb = pmc->tomb;
+                       im->sources = pmc->sources;
+                       for (psf = im->sources; psf; psf = psf->sf_next)
+                               psf->sf_crcount = im->crcount;
                }
                in_dev_put(pmc->interface);
                kfree(pmc);
        }
+       spin_unlock_bh(&im->lock);
 }
 
+/*
+ * flush ip_mc_list deleted records
+ */
 static void igmpv3_clear_delrec(struct in_device *in_dev)
 {
        struct ip_mc_list *pmc, *nextpmc;
@@ -1251,7 +1288,7 @@ void ip_mc_inc_group(struct in_device *in_dev, __be32 addr)
        rcu_assign_pointer(in_dev->mc_list, im);
 
 #ifdef CONFIG_IP_MULTICAST
-       igmpv3_del_delrec(in_dev, im->multiaddr);
+       igmpv3_del_delrec(in_dev, im);
 #endif
        igmp_group_added(im);
        if (!in_dev->dead)
@@ -1341,8 +1378,12 @@ void ip_mc_remap(struct in_device *in_dev)
 
        ASSERT_RTNL();
 
-       for_each_pmc_rtnl(in_dev, pmc)
+       for_each_pmc_rtnl(in_dev, pmc) {
+#ifdef CONFIG_IP_MULTICAST
+               igmpv3_del_delrec(in_dev, pmc);
+#endif
                igmp_group_added(pmc);
+       }
 }
 
 /* Device going down */
@@ -1363,7 +1404,6 @@ void ip_mc_down(struct in_device *in_dev)
        in_dev->mr_gq_running = 0;
        if (del_timer(&in_dev->mr_gq_timer))
                __in_dev_put(in_dev);
-       igmpv3_clear_delrec(in_dev);
 #endif
 
        ip_mc_dec_group(in_dev, IGMP_ALL_HOSTS);
@@ -1398,8 +1438,12 @@ void ip_mc_up(struct in_device *in_dev)
 
        ip_mc_inc_group(in_dev, IGMP_ALL_HOSTS);
 
-       for_each_pmc_rtnl(in_dev, pmc)
+       for_each_pmc_rtnl(in_dev, pmc) {
+#ifdef CONFIG_IP_MULTICAST
+               igmpv3_del_delrec(in_dev, pmc);
+#endif
                igmp_group_added(pmc);
+       }
 }
 
 /*
@@ -1414,13 +1458,13 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
 
        /* Deactivate timers */
        ip_mc_down(in_dev);
+#ifdef CONFIG_IP_MULTICAST
+       igmpv3_clear_delrec(in_dev);
+#endif
 
        while ((i = rtnl_dereference(in_dev->mc_list)) != NULL) {
                in_dev->mc_list = i->next_rcu;
                in_dev->mc_count--;
-
-               /* We've dropped the groups in ip_mc_down already */
-               ip_mc_clear_src(i);
                ip_ma_put(i);
        }
 }