ipv6 netns: Address labels per namespace

This pacth makes IPv6 address labels per network namespace.
It keeps the global label tables, ip6addrlbl_table, but
adds a 'net' member to each ip6addrlbl_entry.
This new member is taken into account when matching labels.

Changelog
=========
* v1: Initial version
* v2:
  * Minize the penalty when network namespaces are not configured:
      *  the 'net' member is added only if CONFIG_NET_NS is
         defined. This saves space when network namespaces are not
         configured.
      * 'net' value is retrieved with the inlined function
         ip6addrlbl_net() that always return &init_net when
         CONFIG_NET_NS is not defined.
  * 'net' member in ip6addrlbl_entry renamed to the less generic
    'lbl_net' name (helps code search).

Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index bbd3d58..06b2814 100644 (file)
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -121,7 +121,8 @@ static inline int addrconf_finite_timeout(unsigned long timeout)
  */
 extern int                     ipv6_addr_label_init(void);
 extern void                    ipv6_addr_label_rtnl_register(void);
-extern u32                     ipv6_addr_label(const struct in6_addr *addr,
+extern u32                     ipv6_addr_label(struct net *net,
+                                               const struct in6_addr *addr,
                                                int type, int ifindex);
 
 /*

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 9ea4e62..fa43374 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -964,7 +964,8 @@ static inline int ipv6_saddr_preferred(int type)
        return 0;
 }
 
-static int ipv6_get_saddr_eval(struct ipv6_saddr_score *score,
+static int ipv6_get_saddr_eval(struct net *net,
+                              struct ipv6_saddr_score *score,
                               struct ipv6_saddr_dst *dst,
                               int i)
 {
@@ -1043,7 +1044,8 @@ static int ipv6_get_saddr_eval(struct ipv6_saddr_score *score,
                break;
        case IPV6_SADDR_RULE_LABEL:
                /* Rule 6: Prefer matching label */
-               ret = ipv6_addr_label(&score->ifa->addr, score->addr_type,
+               ret = ipv6_addr_label(net,
+                                     &score->ifa->addr, score->addr_type,
                                      score->ifa->idev->dev->ifindex) == dst->label;
                break;
 #ifdef CONFIG_IPV6_PRIVACY
@@ -1097,7 +1099,7 @@ int ipv6_dev_get_saddr(struct net_device *dst_dev,
        dst.addr = daddr;
        dst.ifindex = dst_dev ? dst_dev->ifindex : 0;
        dst.scope = __ipv6_addr_src_scope(dst_type);
-       dst.label = ipv6_addr_label(daddr, dst_type, dst.ifindex);
+       dst.label = ipv6_addr_label(net, daddr, dst_type, dst.ifindex);
        dst.prefs = prefs;
 
        hiscore->rule = -1;
@@ -1165,8 +1167,8 @@ int ipv6_dev_get_saddr(struct net_device *dst_dev,
                        for (i = 0; i < IPV6_SADDR_RULE_MAX; i++) {
                                int minihiscore, miniscore;
 
-                               minihiscore = ipv6_get_saddr_eval(hiscore, &dst, i);
-                               miniscore = ipv6_get_saddr_eval(score, &dst, i);
+                               minihiscore = ipv6_get_saddr_eval(net, hiscore, &dst, i);
+                               miniscore = ipv6_get_saddr_eval(net, score, &dst, i);
 
                                if (minihiscore > miniscore) {
                                        if (i == IPV6_SADDR_RULE_SCOPE &&

diff --git a/net/ipv6/addrlabel.c b/net/ipv6/addrlabel.c
index 9bfa884..0890903 100644 (file)
--- a/net/ipv6/addrlabel.c
+++ b/net/ipv6/addrlabel.c
@@ -29,6 +29,9 @@
  */
 struct ip6addrlbl_entry
 {
+#ifdef CONFIG_NET_NS
+       struct net *lbl_net;
+#endif
        struct in6_addr prefix;
        int prefixlen;
        int ifindex;
@@ -46,6 +49,16 @@ static struct ip6addrlbl_table
        u32 seq;
 } ip6addrlbl_table;
 
+static inline
+struct net *ip6addrlbl_net(const struct ip6addrlbl_entry *lbl)
+{
+#ifdef CONFIG_NET_NS
+       return lbl->lbl_net;
+#else
+       return &init_net;
+#endif
+}
+
 /*
  * Default policy table (RFC3484 + extensions)
  *
@@ -65,7 +78,7 @@ static struct ip6addrlbl_table
 
 #define IPV6_ADDR_LABEL_DEFAULT        0xffffffffUL
 
-static const __initdata struct ip6addrlbl_init_table
+static const __net_initdata struct ip6addrlbl_init_table
 {
        const struct in6_addr *prefix;
        int prefixlen;
@@ -108,6 +121,9 @@ static const __initdata struct ip6addrlbl_init_table
 /* Object management */
 static inline void ip6addrlbl_free(struct ip6addrlbl_entry *p)
 {
+#ifdef CONFIG_NET_NS
+       release_net(p->lbl_net);
+#endif
        kfree(p);
 }
 
@@ -128,10 +144,13 @@ static inline void ip6addrlbl_put(struct ip6addrlbl_entry *p)
 }
 
 /* Find label */
-static int __ip6addrlbl_match(struct ip6addrlbl_entry *p,
+static int __ip6addrlbl_match(struct net *net,
+                             struct ip6addrlbl_entry *p,
                              const struct in6_addr *addr,
                              int addrtype, int ifindex)
 {
+       if (!net_eq(ip6addrlbl_net(p), net))
+               return 0;
        if (p->ifindex && p->ifindex != ifindex)
                return 0;
        if (p->addrtype && p->addrtype != addrtype)
@@ -141,19 +160,21 @@ static int __ip6addrlbl_match(struct ip6addrlbl_entry *p,
        return 1;
 }
 
-static struct ip6addrlbl_entry *__ipv6_addr_label(const struct in6_addr *addr,
+static struct ip6addrlbl_entry *__ipv6_addr_label(struct net *net,
+                                                 const struct in6_addr *addr,
                                                  int type, int ifindex)
 {
        struct hlist_node *pos;
        struct ip6addrlbl_entry *p;
        hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
-               if (__ip6addrlbl_match(p, addr, type, ifindex))
+               if (__ip6addrlbl_match(net, p, addr, type, ifindex))
                        return p;
        }
        return NULL;
 }
 
-u32 ipv6_addr_label(const struct in6_addr *addr, int type, int ifindex)
+u32 ipv6_addr_label(struct net *net,
+                   const struct in6_addr *addr, int type, int ifindex)
 {
        u32 label;
        struct ip6addrlbl_entry *p;
@@ -161,7 +182,7 @@ u32 ipv6_addr_label(const struct in6_addr *addr, int type, int ifindex)
        type &= IPV6_ADDR_MAPPED | IPV6_ADDR_COMPATv4 | IPV6_ADDR_LOOPBACK;
 
        rcu_read_lock();
-       p = __ipv6_addr_label(addr, type, ifindex);
+       p = __ipv6_addr_label(net, addr, type, ifindex);
        label = p ? p->label : IPV6_ADDR_LABEL_DEFAULT;
        rcu_read_unlock();
 
@@ -174,7 +195,8 @@ u32 ipv6_addr_label(const struct in6_addr *addr, int type, int ifindex)
 }
 
 /* allocate one entry */
-static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
+static struct ip6addrlbl_entry *ip6addrlbl_alloc(struct net *net,
+                                                const struct in6_addr *prefix,
                                                 int prefixlen, int ifindex,
                                                 u32 label)
 {
@@ -216,6 +238,9 @@ static struct ip6addrlbl_entry *ip6addrlbl_alloc(const struct in6_addr *prefix,
        newp->addrtype = addrtype;
        newp->label = label;
        INIT_HLIST_NODE(&newp->list);
+#ifdef CONFIG_NET_NS
+       newp->lbl_net = hold_net(net);
+#endif
        atomic_set(&newp->refcnt, 1);
        return newp;
 }
@@ -237,6 +262,7 @@ static int __ip6addrlbl_add(struct ip6addrlbl_entry *newp, int replace)
                hlist_for_each_entry_safe(p, pos, n,
                                          &ip6addrlbl_table.head, list) {
                        if (p->prefixlen == newp->prefixlen &&
+                           net_eq(ip6addrlbl_net(p), ip6addrlbl_net(newp)) &&
                            p->ifindex == newp->ifindex &&
                            ipv6_addr_equal(&p->prefix, &newp->prefix)) {
                                if (!replace) {
@@ -261,7 +287,8 @@ out:
 }
 
 /* add a label */
-static int ip6addrlbl_add(const struct in6_addr *prefix, int prefixlen,
+static int ip6addrlbl_add(struct net *net,
+                         const struct in6_addr *prefix, int prefixlen,
                          int ifindex, u32 label, int replace)
 {
        struct ip6addrlbl_entry *newp;
@@ -274,7 +301,7 @@ static int ip6addrlbl_add(const struct in6_addr *prefix, int prefixlen,
                        (unsigned int)label,
                        replace);
 
-       newp = ip6addrlbl_alloc(prefix, prefixlen, ifindex, label);
+       newp = ip6addrlbl_alloc(net, prefix, prefixlen, ifindex, label);
        if (IS_ERR(newp))
                return PTR_ERR(newp);
        spin_lock(&ip6addrlbl_table.lock);
@@ -286,7 +313,8 @@ static int ip6addrlbl_add(const struct in6_addr *prefix, int prefixlen,
 }
 
 /* remove a label */
-static int __ip6addrlbl_del(const struct in6_addr *prefix, int prefixlen,
+static int __ip6addrlbl_del(struct net *net,
+                           const struct in6_addr *prefix, int prefixlen,
                            int ifindex)
 {
        struct ip6addrlbl_entry *p = NULL;
@@ -300,6 +328,7 @@ static int __ip6addrlbl_del(const struct in6_addr *prefix, int prefixlen,
 
        hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
                if (p->prefixlen == prefixlen &&
+                   net_eq(ip6addrlbl_net(p), net) &&
                    p->ifindex == ifindex &&
                    ipv6_addr_equal(&p->prefix, prefix)) {
                        hlist_del_rcu(&p->list);
@@ -311,7 +340,8 @@ static int __ip6addrlbl_del(const struct in6_addr *prefix, int prefixlen,
        return ret;
 }
 
-static int ip6addrlbl_del(const struct in6_addr *prefix, int prefixlen,
+static int ip6addrlbl_del(struct net *net,
+                         const struct in6_addr *prefix, int prefixlen,
                          int ifindex)
 {
        struct in6_addr prefix_buf;
@@ -324,13 +354,13 @@ static int ip6addrlbl_del(const struct in6_addr *prefix, int prefixlen,
 
        ipv6_addr_prefix(&prefix_buf, prefix, prefixlen);
        spin_lock(&ip6addrlbl_table.lock);
-       ret = __ip6addrlbl_del(&prefix_buf, prefixlen, ifindex);
+       ret = __ip6addrlbl_del(net, &prefix_buf, prefixlen, ifindex);
        spin_unlock(&ip6addrlbl_table.lock);
        return ret;
 }
 
 /* add default label */
-static __init int ip6addrlbl_init(void)
+static int __net_init ip6addrlbl_net_init(struct net *net)
 {
        int err = 0;
        int i;
@@ -338,7 +368,8 @@ static __init int ip6addrlbl_init(void)
        ADDRLABEL(KERN_DEBUG "%s()\n", __func__);
 
        for (i = 0; i < ARRAY_SIZE(ip6addrlbl_init_table); i++) {
-               int ret = ip6addrlbl_add(ip6addrlbl_init_table[i].prefix,
+               int ret = ip6addrlbl_add(net,
+                                        ip6addrlbl_init_table[i].prefix,
                                         ip6addrlbl_init_table[i].prefixlen,
                                         0,
                                         ip6addrlbl_init_table[i].label, 0);
@@ -349,11 +380,32 @@ static __init int ip6addrlbl_init(void)
        return err;
 }
 
+static void __net_exit ip6addrlbl_net_exit(struct net *net)
+{
+       struct ip6addrlbl_entry *p = NULL;
+       struct hlist_node *pos, *n;
+
+       /* Remove all labels belonging to the exiting net */
+       spin_lock(&ip6addrlbl_table.lock);
+       hlist_for_each_entry_safe(p, pos, n, &ip6addrlbl_table.head, list) {
+               if (net_eq(ip6addrlbl_net(p), net)) {
+                       hlist_del_rcu(&p->list);
+                       ip6addrlbl_put(p);
+               }
+       }
+       spin_unlock(&ip6addrlbl_table.lock);
+}
+
+static struct pernet_operations ipv6_addr_label_ops = {
+       .init = ip6addrlbl_net_init,
+       .exit = ip6addrlbl_net_exit,
+};
+
 int __init ipv6_addr_label_init(void)
 {
        spin_lock_init(&ip6addrlbl_table.lock);
 
-       return ip6addrlbl_init();
+       return register_pernet_subsys(&ipv6_addr_label_ops);
 }
 
 static const struct nla_policy ifal_policy[IFAL_MAX+1] = {
@@ -371,9 +423,6 @@ static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
        u32 label;
        int err = 0;
 
-       if (net != &init_net)
-               return 0;
-
        err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
        if (err < 0)
                return err;
@@ -385,7 +434,7 @@ static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
                return -EINVAL;
 
        if (ifal->ifal_index &&
-           !__dev_get_by_index(&init_net, ifal->ifal_index))
+           !__dev_get_by_index(net, ifal->ifal_index))
                return -EINVAL;
 
        if (!tb[IFAL_ADDRESS])
@@ -403,12 +452,12 @@ static int ip6addrlbl_newdel(struct sk_buff *skb, struct nlmsghdr *nlh,
 
        switch(nlh->nlmsg_type) {
        case RTM_NEWADDRLABEL:
-               err = ip6addrlbl_add(pfx, ifal->ifal_prefixlen,
+               err = ip6addrlbl_add(net, pfx, ifal->ifal_prefixlen,
                                     ifal->ifal_index, label,
                                     nlh->nlmsg_flags & NLM_F_REPLACE);
                break;
        case RTM_DELADDRLABEL:
-               err = ip6addrlbl_del(pfx, ifal->ifal_prefixlen,
+               err = ip6addrlbl_del(net, pfx, ifal->ifal_prefixlen,
                                     ifal->ifal_index);
                break;
        default:
@@ -458,12 +507,10 @@ static int ip6addrlbl_dump(struct sk_buff *skb, struct netlink_callback *cb)
        int idx = 0, s_idx = cb->args[0];
        int err;
 
-       if (net != &init_net)
-               return 0;
-
        rcu_read_lock();
        hlist_for_each_entry_rcu(p, pos, &ip6addrlbl_table.head, list) {
-               if (idx >= s_idx) {
+               if (idx >= s_idx &&
+                   net_eq(ip6addrlbl_net(p), net)) {
                        if ((err = ip6addrlbl_fill(skb, p,
                                                   ip6addrlbl_table.seq,
                                                   NETLINK_CB(cb->skb).pid,
@@ -499,9 +546,6 @@ static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
        struct ip6addrlbl_entry *p;
        struct sk_buff *skb;
 
-       if (net != &init_net)
-               return 0;
-
        err = nlmsg_parse(nlh, sizeof(*ifal), tb, IFAL_MAX, ifal_policy);
        if (err < 0)
                return err;
@@ -513,7 +557,7 @@ static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
                return -EINVAL;
 
        if (ifal->ifal_index &&
-           !__dev_get_by_index(&init_net, ifal->ifal_index))
+           !__dev_get_by_index(net, ifal->ifal_index))
                return -EINVAL;
 
        if (!tb[IFAL_ADDRESS])
@@ -524,7 +568,7 @@ static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
                return -EINVAL;
 
        rcu_read_lock();
-       p = __ipv6_addr_label(addr, ipv6_addr_type(addr), ifal->ifal_index);
+       p = __ipv6_addr_label(net, addr, ipv6_addr_type(addr), ifal->ifal_index);
        if (p && ip6addrlbl_hold(p))
                p = NULL;
        lseq = ip6addrlbl_table.seq;
@@ -552,7 +596,7 @@ static int ip6addrlbl_get(struct sk_buff *in_skb, struct nlmsghdr* nlh,
                goto out;
        }
 
-       err = rtnl_unicast(skb, &init_net, NETLINK_CB(in_skb).pid);
+       err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
 out:
        return err;
 }