ipv6 addrconf: introduce IFA_F_MANAGETEMPADDR to tell kernel to manage temporary addresses
Creating an address with this flag set will result in kernel taking care
of temporary addresses in the same way as if the address was created by
kernel itself (after RA receive). This allows userspace applications
implementing the autoconfiguration (NetworkManager for example) to
implement ipv6 addresses privacy.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Thomas Haller <thaller@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 334a7e1..5087cc5 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1024,7 +1024,7 @@
u32 addr_flags;
unsigned long now = jiffies;
- write_lock(&idev->lock);
+ write_lock_bh(&idev->lock);
if (ift) {
spin_lock_bh(&ift->lock);
memcpy(&addr.s6_addr[8], &ift->addr.s6_addr[8], 8);
@@ -1036,7 +1036,7 @@
retry:
in6_dev_hold(idev);
if (idev->cnf.use_tempaddr <= 0) {
- write_unlock(&idev->lock);
+ write_unlock_bh(&idev->lock);
pr_info("%s: use_tempaddr is disabled\n", __func__);
in6_dev_put(idev);
ret = -1;
@@ -1046,7 +1046,7 @@
if (ifp->regen_count++ >= idev->cnf.regen_max_retry) {
idev->cnf.use_tempaddr = -1; /*XXX*/
spin_unlock_bh(&ifp->lock);
- write_unlock(&idev->lock);
+ write_unlock_bh(&idev->lock);
pr_warn("%s: regeneration time exceeded - disabled temporary address support\n",
__func__);
in6_dev_put(idev);
@@ -1072,7 +1072,7 @@
regen_advance = idev->cnf.regen_max_retry *
idev->cnf.dad_transmits *
idev->nd_parms->retrans_time / HZ;
- write_unlock(&idev->lock);
+ write_unlock_bh(&idev->lock);
/* A temporary address is created only if this calculated Preferred
* Lifetime is greater than REGEN_ADVANCE time units. In particular,
@@ -1099,7 +1099,7 @@
in6_dev_put(idev);
pr_info("%s: retry temporary address regeneration\n", __func__);
tmpaddr = &addr;
- write_lock(&idev->lock);
+ write_lock_bh(&idev->lock);
goto retry;
}
@@ -2016,6 +2016,73 @@
return idev;
}
+static void manage_tempaddrs(struct inet6_dev *idev,
+ struct inet6_ifaddr *ifp,
+ __u32 valid_lft, __u32 prefered_lft,
+ bool create, unsigned long now)
+{
+ u32 flags;
+ struct inet6_ifaddr *ift;
+
+ read_lock_bh(&idev->lock);
+ /* update all temporary addresses in the list */
+ list_for_each_entry(ift, &idev->tempaddr_list, tmp_list) {
+ int age, max_valid, max_prefered;
+
+ if (ifp != ift->ifpub)
+ continue;
+
+ /* RFC 4941 section 3.3:
+ * If a received option will extend the lifetime of a public
+ * address, the lifetimes of temporary addresses should
+ * be extended, subject to the overall constraint that no
+ * temporary addresses should ever remain "valid" or "preferred"
+ * for a time longer than (TEMP_VALID_LIFETIME) or
+ * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR), respectively.
+ */
+ age = (now - ift->cstamp) / HZ;
+ max_valid = idev->cnf.temp_valid_lft - age;
+ if (max_valid < 0)
+ max_valid = 0;
+
+ max_prefered = idev->cnf.temp_prefered_lft -
+ idev->cnf.max_desync_factor - age;
+ if (max_prefered < 0)
+ max_prefered = 0;
+
+ if (valid_lft > max_valid)
+ valid_lft = max_valid;
+
+ if (prefered_lft > max_prefered)
+ prefered_lft = max_prefered;
+
+ spin_lock(&ift->lock);
+ flags = ift->flags;
+ ift->valid_lft = valid_lft;
+ ift->prefered_lft = prefered_lft;
+ ift->tstamp = now;
+ if (prefered_lft > 0)
+ ift->flags &= ~IFA_F_DEPRECATED;
+
+ spin_unlock(&ift->lock);
+ if (!(flags&IFA_F_TENTATIVE))
+ ipv6_ifa_notify(0, ift);
+ }
+
+ if ((create || list_empty(&idev->tempaddr_list)) &&
+ idev->cnf.use_tempaddr > 0) {
+ /* When a new public address is created as described
+ * in [ADDRCONF], also create a new temporary address.
+ * Also create a temporary address if it's enabled but
+ * no temporary address currently exists.
+ */
+ read_unlock_bh(&idev->lock);
+ ipv6_create_tempaddr(ifp, NULL);
+ } else {
+ read_unlock_bh(&idev->lock);
+ }
+}
+
void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
{
struct prefix_info *pinfo;
@@ -2170,6 +2237,7 @@
return;
}
+ ifp->flags |= IFA_F_MANAGETEMPADDR;
update_lft = 0;
create = 1;
ifp->cstamp = jiffies;
@@ -2180,7 +2248,6 @@
if (ifp) {
u32 flags;
unsigned long now;
- struct inet6_ifaddr *ift;
u32 stored_lft;
/* update lifetime (RFC2462 5.5.3 e) */
@@ -2221,70 +2288,8 @@
} else
spin_unlock(&ifp->lock);
- read_lock_bh(&in6_dev->lock);
- /* update all temporary addresses in the list */
- list_for_each_entry(ift, &in6_dev->tempaddr_list,
- tmp_list) {
- int age, max_valid, max_prefered;
-
- if (ifp != ift->ifpub)
- continue;
-
- /*
- * RFC 4941 section 3.3:
- * If a received option will extend the lifetime
- * of a public address, the lifetimes of
- * temporary addresses should be extended,
- * subject to the overall constraint that no
- * temporary addresses should ever remain
- * "valid" or "preferred" for a time longer than
- * (TEMP_VALID_LIFETIME) or
- * (TEMP_PREFERRED_LIFETIME - DESYNC_FACTOR),
- * respectively.
- */
- age = (now - ift->cstamp) / HZ;
- max_valid = in6_dev->cnf.temp_valid_lft - age;
- if (max_valid < 0)
- max_valid = 0;
-
- max_prefered = in6_dev->cnf.temp_prefered_lft -
- in6_dev->cnf.max_desync_factor -
- age;
- if (max_prefered < 0)
- max_prefered = 0;
-
- if (valid_lft > max_valid)
- valid_lft = max_valid;
-
- if (prefered_lft > max_prefered)
- prefered_lft = max_prefered;
-
- spin_lock(&ift->lock);
- flags = ift->flags;
- ift->valid_lft = valid_lft;
- ift->prefered_lft = prefered_lft;
- ift->tstamp = now;
- if (prefered_lft > 0)
- ift->flags &= ~IFA_F_DEPRECATED;
-
- spin_unlock(&ift->lock);
- if (!(flags&IFA_F_TENTATIVE))
- ipv6_ifa_notify(0, ift);
- }
-
- if ((create || list_empty(&in6_dev->tempaddr_list)) && in6_dev->cnf.use_tempaddr > 0) {
- /*
- * When a new public address is created as
- * described in [ADDRCONF], also create a new
- * temporary address. Also create a temporary
- * address if it's enabled but no temporary
- * address currently exists.
- */
- read_unlock_bh(&in6_dev->lock);
- ipv6_create_tempaddr(ifp, NULL);
- } else {
- read_unlock_bh(&in6_dev->lock);
- }
+ manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
+ create, now);
in6_ifa_put(ifp);
addrconf_verify(0);
@@ -2386,6 +2391,9 @@
if (!valid_lft || prefered_lft > valid_lft)
return -EINVAL;
+ if (ifa_flags & IFA_F_MANAGETEMPADDR && plen != 64)
+ return -EINVAL;
+
dev = __dev_get_by_index(net, ifindex);
if (!dev)
return -ENODEV;
@@ -2426,6 +2434,9 @@
* manually configured addresses
*/
addrconf_dad_start(ifp);
+ if (ifa_flags & IFA_F_MANAGETEMPADDR)
+ manage_tempaddrs(idev, ifp, valid_lft, prefered_lft,
+ true, jiffies);
in6_ifa_put(ifp);
addrconf_verify(0);
return 0;
@@ -3603,10 +3614,15 @@
u32 flags;
clock_t expires;
unsigned long timeout;
+ bool was_managetempaddr;
if (!valid_lft || (prefered_lft > valid_lft))
return -EINVAL;
+ if (ifa_flags & IFA_F_MANAGETEMPADDR &&
+ (ifp->flags & IFA_F_TEMPORARY || ifp->prefix_len != 64))
+ return -EINVAL;
+
timeout = addrconf_timeout_fixup(valid_lft, HZ);
if (addrconf_finite_timeout(timeout)) {
expires = jiffies_to_clock_t(timeout * HZ);
@@ -3626,7 +3642,10 @@
}
spin_lock_bh(&ifp->lock);
- ifp->flags = (ifp->flags & ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD | IFA_F_HOMEADDRESS)) | ifa_flags;
+ was_managetempaddr = ifp->flags & IFA_F_MANAGETEMPADDR;
+ ifp->flags &= ~(IFA_F_DEPRECATED | IFA_F_PERMANENT | IFA_F_NODAD |
+ IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR);
+ ifp->flags |= ifa_flags;
ifp->tstamp = jiffies;
ifp->valid_lft = valid_lft;
ifp->prefered_lft = prefered_lft;
@@ -3637,6 +3656,14 @@
addrconf_prefix_route(&ifp->addr, ifp->prefix_len, ifp->idev->dev,
expires, flags);
+
+ if (was_managetempaddr || ifp->flags & IFA_F_MANAGETEMPADDR) {
+ if (was_managetempaddr && !(ifp->flags & IFA_F_MANAGETEMPADDR))
+ valid_lft = prefered_lft = 0;
+ manage_tempaddrs(ifp->idev, ifp, valid_lft, prefered_lft,
+ !was_managetempaddr, jiffies);
+ }
+
addrconf_verify(0);
return 0;
@@ -3682,7 +3709,7 @@
ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) : ifm->ifa_flags;
/* We ignore other flags so far. */
- ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS;
+ ifa_flags &= IFA_F_NODAD | IFA_F_HOMEADDRESS | IFA_F_MANAGETEMPADDR;
ifa = ipv6_get_ifaddr(net, pfx, dev, 1);
if (ifa == NULL) {
