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authorErik Kline <ek@google.com>2015-07-22 09:38:25 +0200
committerDavid S. Miller <davem@davemloft.net>2015-07-22 19:54:11 +0200
commit3985e8a3611a93bb36789f65db862e5700aab65e (patch)
tree667800cbbe808601389a59754448cdf237a51ab8
parentr8152: support the new RTL8153 chip (diff)
downloadlinux-3985e8a3611a93bb36789f65db862e5700aab65e.tar.xz
linux-3985e8a3611a93bb36789f65db862e5700aab65e.zip
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 <ek@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--Documentation/networking/ip-sysctl.txt7
-rw-r--r--include/linux/ipv6.h1
-rw-r--r--include/uapi/linux/ipv6.h1
-rw-r--r--net/ipv6/addrconf.c22
4 files changed, 28 insertions, 3 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index f63aeefd2c24..1a5ab21bcca5 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -1460,6 +1460,13 @@ router_solicitations - INTEGER
routers are present.
Default: 3
+use_oif_addrs_only - BOOLEAN
+ When enabled, the candidate source addresses for destinations
+ routed via this interface are restricted to the set of addresses
+ configured on this interface (vis. RFC 6724, section 4).
+
+ Default: false
+
use_tempaddr - INTEGER
Preference for Privacy Extensions (RFC3041).
<= 0 : disable Privacy Extensions
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 1319a6bb6b82..06ed637225b8 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -57,6 +57,7 @@ struct ipv6_devconf {
bool initialized;
struct in6_addr secret;
} stable_secret;
+ __s32 use_oif_addrs_only;
void *sysctl;
};
diff --git a/include/uapi/linux/ipv6.h b/include/uapi/linux/ipv6.h
index 5efa54ae567c..641a146ead7d 100644
--- a/include/uapi/linux/ipv6.h
+++ b/include/uapi/linux/ipv6.h
@@ -171,6 +171,7 @@ enum {
DEVCONF_USE_OPTIMISTIC,
DEVCONF_ACCEPT_RA_MTU,
DEVCONF_STABLE_SECRET,
+ DEVCONF_USE_OIF_ADDRS_ONLY,
DEVCONF_MAX
};
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 32153c248959..eb0c6a3a8a00 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -211,7 +211,8 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = {
.accept_ra_mtu = 1,
.stable_secret = {
.initialized = false,
- }
+ },
+ .use_oif_addrs_only = 0,
};
static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
@@ -253,6 +254,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
.stable_secret = {
.initialized = false,
},
+ .use_oif_addrs_only = 0,
};
/* Check if a valid qdisc is available */
@@ -1472,11 +1474,16 @@ 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)
*/
if (dst_dev) {
+ idev = __in6_dev_get(dst_dev);
if ((dst_type & IPV6_ADDR_MULTICAST) ||
- dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL) {
- idev = __in6_dev_get(dst_dev);
+ dst.scope <= IPV6_ADDR_SCOPE_LINKLOCAL ||
+ (idev && idev->cnf.use_oif_addrs_only)) {
use_oif_addr = true;
}
}
@@ -4607,6 +4614,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
array[DEVCONF_ACCEPT_RA_FROM_LOCAL] = cnf->accept_ra_from_local;
array[DEVCONF_ACCEPT_RA_MTU] = cnf->accept_ra_mtu;
/* we omit DEVCONF_STABLE_SECRET for now */
+ array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
}
static inline size_t inet6_ifla6_size(void)
@@ -5606,6 +5614,14 @@ static struct addrconf_sysctl_table
.proc_handler = addrconf_sysctl_stable_secret,
},
{
+ .procname = "use_oif_addrs_only",
+ .data = &ipv6_devconf.use_oif_addrs_only,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_dointvec,
+
+ },
+ {
/* sentinel */
}
},