From 2f78e06636061d0b179c6bbf3b50051faec0f7aa Mon Sep 17 00:00:00 2001 From: Erik Kline Date: Wed, 22 Jul 2015 16:38:25 +0900 Subject: ipv6: sysctl to restrict candidate source addresses Per RFC 6724, section 4, "Candidate Source Addresses": It is RECOMMENDED that the candidate source addresses be the set of unicast addresses assigned to the interface that will be used to send to the destination (the "outgoing" interface). Add a sysctl to enable this behaviour. Signed-off-by: Erik Kline Signed-off-by: David S. Miller [Simplified back-port of net-next 3985e8a3611a93bb36789f65db862e5700aab65e] Bug: 19470192 Bug: 21832279 Bug: 22464419 Change-Id: Ib74ef945dcabe64215064f15ee1660b6524d65ce --- net/ipv6/addrconf.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) (limited to 'net') diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 41f4f7767..3428afb5b 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -208,6 +208,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = { .accept_source_route = 0, /* we do not accept RH0 by default. */ .disable_ipv6 = 0, .accept_dad = 1, + .use_oif_addrs_only = 0, }; static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = { @@ -243,6 +244,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = { .accept_source_route = 0, /* we do not accept RH0 by default. */ .disable_ipv6 = 0, .accept_dad = 1, + .use_oif_addrs_only = 0, }; /* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */ @@ -1391,9 +1393,15 @@ int ipv6_dev_get_saddr(struct net *net, const struct net_device *dst_dev, * include addresses assigned to interfaces * belonging to the same site as the outgoing * interface.) + * - "It is RECOMMENDED that the candidate source addresses + * be the set of unicast addresses assigned to the + * interface that will be used to send to the destination + * (the 'outgoing' interface)." (RFC 6724) */ + idev = dst_dev ? __in6_dev_get(dst_dev) : NULL; if (((dst_type & IPV6_ADDR_MULTICAST) || - dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) && + dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL || + (idev && idev->cnf.use_oif_addrs_only)) && dst.ifindex && dev->ifindex != dst.ifindex) continue; @@ -4375,6 +4383,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf, array[DEVCONF_ACCEPT_DAD] = cnf->accept_dad; array[DEVCONF_FORCE_TLLAO] = cnf->force_tllao; array[DEVCONF_NDISC_NOTIFY] = cnf->ndisc_notify; + array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only; } static inline size_t inet6_ifla6_size(void) @@ -5226,6 +5235,14 @@ static struct addrconf_sysctl_table .mode = 0644, .proc_handler = proc_dointvec }, + { + .procname = "use_oif_addrs_only", + .data = &ipv6_devconf.use_oif_addrs_only, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + + }, { /* sentinel */ } -- cgit v1.2.3