addrconf: put prefix address add in an own function

This patch moves the functionality to add a RA PIO prefix generated
address in an own function. This move prepares to add a hook for
adding a second address for a second link-layer address. E.g. short
address for 802.15.4 6LoWPAN.

Cc: David S. Miller <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 1ce4048..44c1cef 100644 (file)
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2333,12 +2333,110 @@ static bool is_addr_mode_generate_stable(struct inet6_dev *idev)
               idev->addr_gen_mode == IN6_ADDR_GEN_MODE_RANDOM;
 }
 
+static int addrconf_prefix_rcv_add_addr(struct net *net,
+                                       struct net_device *dev,
+                                       const struct prefix_info *pinfo,
+                                       struct inet6_dev *in6_dev,
+                                       const struct in6_addr *addr,
+                                       int addr_type, u32 addr_flags,
+                                       bool sllao, bool tokenized,
+                                       __u32 valid_lft, u32 prefered_lft)
+{
+       struct inet6_ifaddr *ifp = ipv6_get_ifaddr(net, addr, dev, 1);
+       int create = 0, update_lft = 0;
+
+       if (!ifp && valid_lft) {
+               int max_addresses = in6_dev->cnf.max_addresses;
+
+#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
+               if (in6_dev->cnf.optimistic_dad &&
+                   !net->ipv6.devconf_all->forwarding && sllao)
+                       addr_flags |= IFA_F_OPTIMISTIC;
+#endif
+
+               /* Do not allow to create too much of autoconfigured
+                * addresses; this would be too easy way to crash kernel.
+                */
+               if (!max_addresses ||
+                   ipv6_count_addresses(in6_dev) < max_addresses)
+                       ifp = ipv6_add_addr(in6_dev, addr, NULL,
+                                           pinfo->prefix_len,
+                                           addr_type&IPV6_ADDR_SCOPE_MASK,
+                                           addr_flags, valid_lft,
+                                           prefered_lft);
+
+               if (IS_ERR_OR_NULL(ifp))
+                       return -1;
+
+               update_lft = 0;
+               create = 1;
+               spin_lock_bh(&ifp->lock);
+               ifp->flags |= IFA_F_MANAGETEMPADDR;
+               ifp->cstamp = jiffies;
+               ifp->tokenized = tokenized;
+               spin_unlock_bh(&ifp->lock);
+               addrconf_dad_start(ifp);
+       }
+
+       if (ifp) {
+               u32 flags;
+               unsigned long now;
+               u32 stored_lft;
+
+               /* update lifetime (RFC2462 5.5.3 e) */
+               spin_lock_bh(&ifp->lock);
+               now = jiffies;
+               if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
+                       stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
+               else
+                       stored_lft = 0;
+               if (!update_lft && !create && stored_lft) {
+                       const u32 minimum_lft = min_t(u32,
+                               stored_lft, MIN_VALID_LIFETIME);
+                       valid_lft = max(valid_lft, minimum_lft);
+
+                       /* RFC4862 Section 5.5.3e:
+                        * "Note that the preferred lifetime of the
+                        *  corresponding address is always reset to
+                        *  the Preferred Lifetime in the received
+                        *  Prefix Information option, regardless of
+                        *  whether the valid lifetime is also reset or
+                        *  ignored."
+                        *
+                        * So we should always update prefered_lft here.
+                        */
+                       update_lft = 1;
+               }
+
+               if (update_lft) {
+                       ifp->valid_lft = valid_lft;
+                       ifp->prefered_lft = prefered_lft;
+                       ifp->tstamp = now;
+                       flags = ifp->flags;
+                       ifp->flags &= ~IFA_F_DEPRECATED;
+                       spin_unlock_bh(&ifp->lock);
+
+                       if (!(flags&IFA_F_TENTATIVE))
+                               ipv6_ifa_notify(0, ifp);
+               } else
+                       spin_unlock_bh(&ifp->lock);
+
+               manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
+                                create, now);
+
+               in6_ifa_put(ifp);
+               addrconf_verify();
+       }
+
+       return 0;
+}
+
 void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
 {
        struct prefix_info *pinfo;
        __u32 valid_lft;
        __u32 prefered_lft;
-       int addr_type;
+       int addr_type, err;
        u32 addr_flags = 0;
        struct inet6_dev *in6_dev;
        struct net *net = dev_net(dev);
@@ -2432,9 +2530,7 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
        /* Try to figure out our local address for this prefix */
 
        if (pinfo->autoconf && in6_dev->cnf.autoconf) {
-               struct inet6_ifaddr *ifp;
                struct in6_addr addr;
-               int create = 0, update_lft = 0;
                bool tokenized = false;
 
                if (pinfo->prefix_len == 64) {
@@ -2453,106 +2549,25 @@ void addrconf_prefix_rcv(struct net_device *dev, u8 *opt, int len, bool sllao)
                                goto ok;
                        } else if (ipv6_generate_eui64(addr.s6_addr + 8, dev) &&
                                   ipv6_inherit_eui64(addr.s6_addr + 8, in6_dev)) {
-                               in6_dev_put(in6_dev);
-                               return;
+                               goto put;
                        }
                        goto ok;
                }
                net_dbg_ratelimited("IPv6 addrconf: prefix with wrong length %d\n",
                                    pinfo->prefix_len);
-               in6_dev_put(in6_dev);
-               return;
+               goto put;
 
 ok:
-
-               ifp = ipv6_get_ifaddr(net, &addr, dev, 1);
-
-               if (!ifp && valid_lft) {
-                       int max_addresses = in6_dev->cnf.max_addresses;
-
-#ifdef CONFIG_IPV6_OPTIMISTIC_DAD
-                       if (in6_dev->cnf.optimistic_dad &&
-                           !net->ipv6.devconf_all->forwarding && sllao)
-                               addr_flags |= IFA_F_OPTIMISTIC;
-#endif
-
-                       /* Do not allow to create too much of autoconfigured
-                        * addresses; this would be too easy way to crash kernel.
-                        */
-                       if (!max_addresses ||
-                           ipv6_count_addresses(in6_dev) < max_addresses)
-                               ifp = ipv6_add_addr(in6_dev, &addr, NULL,
-                                                   pinfo->prefix_len,
-                                                   addr_type&IPV6_ADDR_SCOPE_MASK,
-                                                   addr_flags, valid_lft,
-                                                   prefered_lft);
-
-                       if (IS_ERR_OR_NULL(ifp)) {
-                               in6_dev_put(in6_dev);
-                               return;
-                       }
-
-                       update_lft = 0;
-                       create = 1;
-                       spin_lock_bh(&ifp->lock);
-                       ifp->flags |= IFA_F_MANAGETEMPADDR;
-                       ifp->cstamp = jiffies;
-                       ifp->tokenized = tokenized;
-                       spin_unlock_bh(&ifp->lock);
-                       addrconf_dad_start(ifp);
-               }
-
-               if (ifp) {
-                       u32 flags;
-                       unsigned long now;
-                       u32 stored_lft;
-
-                       /* update lifetime (RFC2462 5.5.3 e) */
-                       spin_lock_bh(&ifp->lock);
-                       now = jiffies;
-                       if (ifp->valid_lft > (now - ifp->tstamp) / HZ)
-                               stored_lft = ifp->valid_lft - (now - ifp->tstamp) / HZ;
-                       else
-                               stored_lft = 0;
-                       if (!update_lft && !create && stored_lft) {
-                               const u32 minimum_lft = min_t(u32,
-                                       stored_lft, MIN_VALID_LIFETIME);
-                               valid_lft = max(valid_lft, minimum_lft);
-
-                               /* RFC4862 Section 5.5.3e:
-                                * "Note that the preferred lifetime of the
-                                *  corresponding address is always reset to
-                                *  the Preferred Lifetime in the received
-                                *  Prefix Information option, regardless of
-                                *  whether the valid lifetime is also reset or
-                                *  ignored."
-                                *
-                                * So we should always update prefered_lft here.
-                                */
-                               update_lft = 1;
-                       }
-
-                       if (update_lft) {
-                               ifp->valid_lft = valid_lft;
-                               ifp->prefered_lft = prefered_lft;
-                               ifp->tstamp = now;
-                               flags = ifp->flags;
-                               ifp->flags &= ~IFA_F_DEPRECATED;
-                               spin_unlock_bh(&ifp->lock);
-
-                               if (!(flags&IFA_F_TENTATIVE))
-                                       ipv6_ifa_notify(0, ifp);
-                       } else
-                               spin_unlock_bh(&ifp->lock);
-
-                       manage_tempaddrs(in6_dev, ifp, valid_lft, prefered_lft,
-                                        create, now);
-
-                       in6_ifa_put(ifp);
-                       addrconf_verify();
-               }
+               err = addrconf_prefix_rcv_add_addr(net, dev, pinfo, in6_dev,
+                                                  &addr, addr_type,
+                                                  addr_flags, sllao,
+                                                  tokenized, valid_lft,
+                                                  prefered_lft);
+               if (err)
+                       goto put;
        }
        inet6_prefix_notify(RTM_NEWPREFIX, in6_dev, pinfo);
+put:
        in6_dev_put(in6_dev);
 }