From 1c8ad5bfa2be5025b0c81e3c2decd0574d453ab1 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 21 May 2013 21:52:54 +0000 Subject: [PATCH] bridge: use the bridge IP addr as source addr for querier Quote from Adam: "If it is believed that the use of 0.0.0.0 as the IP address is what is causing strange behaviour on other devices then is there a good reason that a bridge rather than a router shouldn't be the active querier? If not then using the bridge IP address and having the querier enabled by default may be a reasonable solution (provided that our querier obeys the election rules and shuts up if it sees a query from a lower IP address that isn't 0.0.0.0). Just because a device is the elected querier for IGMP doesn't appear to mean it is required to perform any other routing functions." And introduce a new troggle for it, as suggested by Herbert. Suggested-by: Adam Baker Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Adam Baker Signed-off-by: Cong Wang Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 5 ++++- net/bridge/br_private.h | 1 + net/bridge/br_sysfs_br.c | 26 ++++++++++++++++++++++++++ 3 files changed, 31 insertions(+), 1 deletion(-) diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 81f2389f78eb..247514793101 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #if IS_ENABLED(CONFIG_IPV6) #include @@ -381,7 +382,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br, iph->frag_off = htons(IP_DF); iph->ttl = 1; iph->protocol = IPPROTO_IGMP; - iph->saddr = 0; + iph->saddr = br->multicast_query_use_ifaddr ? + inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0; iph->daddr = htonl(INADDR_ALLHOSTS_GROUP); ((u8 *)&iph[1])[0] = IPOPT_RA; ((u8 *)&iph[1])[1] = 4; @@ -1618,6 +1620,7 @@ void br_multicast_init(struct net_bridge *br) br->multicast_router = 1; br->multicast_querier = 0; + br->multicast_query_use_ifaddr = 0; br->multicast_last_member_count = 2; br->multicast_startup_query_count = 2; diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index d2c043a857b6..e260710a01d4 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -249,6 +249,7 @@ struct net_bridge u8 multicast_disabled:1; u8 multicast_querier:1; + u8 multicast_query_use_ifaddr:1; u32 hash_elasticity; u32 hash_max; diff --git a/net/bridge/br_sysfs_br.c b/net/bridge/br_sysfs_br.c index 8baa9c08e1a4..394bb96b6087 100644 --- a/net/bridge/br_sysfs_br.c +++ b/net/bridge/br_sysfs_br.c @@ -375,6 +375,31 @@ static ssize_t store_multicast_snooping(struct device *d, static DEVICE_ATTR(multicast_snooping, S_IRUGO | S_IWUSR, show_multicast_snooping, store_multicast_snooping); +static ssize_t show_multicast_query_use_ifaddr(struct device *d, + struct device_attribute *attr, + char *buf) +{ + struct net_bridge *br = to_bridge(d); + return sprintf(buf, "%d\n", br->multicast_query_use_ifaddr); +} + +static int set_query_use_ifaddr(struct net_bridge *br, unsigned long val) +{ + br->multicast_query_use_ifaddr = !!val; + return 0; +} + +static ssize_t +store_multicast_query_use_ifaddr(struct device *d, + struct device_attribute *attr, + const char *buf, size_t len) +{ + return store_bridge_parm(d, buf, len, set_query_use_ifaddr); +} +static DEVICE_ATTR(multicast_query_use_ifaddr, S_IRUGO | S_IWUSR, + show_multicast_query_use_ifaddr, + store_multicast_query_use_ifaddr); + static ssize_t show_multicast_querier(struct device *d, struct device_attribute *attr, char *buf) @@ -734,6 +759,7 @@ static struct attribute *bridge_attrs[] = { &dev_attr_multicast_router.attr, &dev_attr_multicast_snooping.attr, &dev_attr_multicast_querier.attr, + &dev_attr_multicast_query_use_ifaddr.attr, &dev_attr_hash_elasticity.attr, &dev_attr_hash_max.attr, &dev_attr_multicast_last_member_count.attr,