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path: root/net/ipv6/addrconf.c
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2006-09-22[IPv6] route: FIB6 configuration using struct fib6_configThomas Graf
Replaces the struct in6_rtmsg based interface orignating from the ioctl interface with a struct fib6_config based on. Allows changing the interface without breaking the ioctl interface and avoids passing on tons of parameters. The recently introduced struct nl_info is used to pass on netlink authorship information for notifications. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv6] route: Simplify ip6_ins_rt()Thomas Graf
Provide a simple ip6_ins_rt() for the majority of users and an alternative for the exception via netlink. Avoids code obfuscation. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv6] route: Simplify ip6_del_rt()Thomas Graf
Provide a simple ip6_del_rt() for the majority of users and an alternative for the exception via netlink. Avoids code obfuscation. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[NET/IPV4/IPV6]: Change some sysctl variables to __read_mostlyBrian Haley
Change net/core, ipv4 and ipv6 sysctl variables to __read_mostly. Couldn't actually measure any performance increase while testing (.3% I consider noise), but seems like the right thing to do. Signed-off-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv6] prefix: Convert prefix notifications to use rtnl_notify()Thomas Graf
Fixes a wrong use of current->pid as netlink pid. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv6] link: Convert link notifications to use rtnl_notify()Thomas Graf
Fixes a wrong use of current->pid as netlink pid. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv6] address: Convert address notification to use rtnl_notify()Thomas Graf
Fixes a wrong use of current->pid as netlink pid. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[RTNETLINK]: Use rtnl_unicast() for rtnetlink unicastsThomas Graf
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPV6]: Protect RTM_GETRULE table entry with IPV6_MULTIPLE_TABLES ifdefDavid S. Miller
This is how IPv4 handles this case too. Based upon a patch from Andrew Morton. Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPv4]: Move interface address bits to linux/if_addr.hThomas Graf
Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPV6]: Policy Routing RulesThomas Graf
Adds support for policy routing rules including a new local table for routes with a local destination. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22[IPV6]: Multiple Routing TablesThomas Graf
Adds the framework to support multiple IPv6 routing tables. Currently all automatically generated routes are put into the same table. This could be changed at a later point after considering the produced locking overhead. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-29[IPV6]: ipv6_add_addr should install dstentry earlierKeir Fraser
ipv6_add_addr allocates a struct inet6_ifaddr and a dstentry, but it doesn't install the dstentry in ifa->rt until after it releases the addrconf_hash_lock. This means other CPUs will be able to see the new address while it hasn't been initialized completely yet. One possible fix would be to grab the ifp->lock spinlock when creating the address struct; a simpler fix is to just move the assignment. Acked-by: jbeulich@novell.com Acked-by: okir@suse.de Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-09[IPV6]: The ifa lock is a BH lockHerbert Xu
The ifa lock is expected to be taken in BH context (by addrconf timers) so we must disable BH when accessing it from user context. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02[IPV6] ADDRCONF: NLM_F_REPLACE support for RTM_NEWADDRNoriaki TAKAMIYA
Based on MIPL2 kernel patch. Signed-off-by: Noriaki YAKAMIYA <takamiya@po.ntts.co.jp> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2006-08-02[IPV6] ADDRCONF: Support get operation of single addressNoriaki TAKAMIYA
Based on MIPL2 kernel patch. Signed-off-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2006-08-02[IPV6] ADDRCONF: Do not verify an address with infinity lifetimeYOSHIFUJI Hideaki
We also do not try regenarating new temporary address corresponding to an address with infinite preferred lifetime. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2006-08-02[IPV6] ADDRCONF: Allow user-space to specify address lifetimeNoriaki TAKAMIYA
Based on MIPL2 kernel patch. Signed-off-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2006-08-02[IPV6] ADDRCONF: Check payload length for IFA_LOCAL attribute in ↵YOSHIFUJI Hideaki
RTM_{ADD,DEL}MSG message Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2006-07-12[IPV6]: Use ipv6_addr_src_scope for link address sorting.YOSHIFUJI Hideaki
In the source address selection, the address must be sorted from global to node-local. But, ifp->scope is different from the scope for source address selection. 2001::1 fe80::1 ::1 ifp->scope 0 0x02 0x01 ipv6_addr_src_scope(&ifp->addr) 0x0e 0x02 0x01 So, we need to use ipv6_addr_src_scope(&ifp->addr) for sorting. And, for backward compatibility, addresses should be sorted from new one to old one. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Acked-by: Brian Haley <brian.haley@hp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-12[IPV6]: order addresses by scopeBrian Haley
If IPv6 addresses are ordered by scope, then ipv6_dev_get_saddr() can break-out of the device addr_list for() loop when the candidate source address scope is less than the destination address scope. Signed-off-by: Brian Haley <brian.haley@hp.com> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30Remove obsolete #include <linux/config.h>Jörn Engel
Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
2006-06-23[IPV6] ADDRCONF: Fix default source address selection without ↵YOSHIFUJI Hideaki
CONFIG_IPV6_PRIVACY We need to update hiscore.rule even if we don't enable CONFIG_IPV6_PRIVACY, because we have more less significant rule; longest match. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23[IPV6]: Fix source address selection.Łukasz Stelmach
Two additional labels (RFC 3484, sec. 10.3) for IPv6 addreses are defined to make a distinction between global unicast addresses and Unique Local Addresses (fc00::/7, RFC 4193) and Teredo (2001::/32, RFC 4380). It is necessary to avoid attempts of connection that would either fail (eg. fec0:: to 2001:feed::) or be sub-optimal (2001:0:: to 2001:feed::). Signed-off-by: Łukasz Stelmach <stlman@poczta.fm> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-17[IPV6]: Sum real space for RTAs.YOSHIFUJI Hideaki
This patch fixes RTNLGRP_IPV6_IFINFO netlink notifications. Issue pointed out by Patrick McHardy <kaber@trash.net>. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Acked-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-27[PATCH] Notifier chain update: API changesAlan Stern
The kernel's implementation of notifier chains is unsafe. There is no protection against entries being added to or removed from a chain while the chain is in use. The issues were discussed in this thread: http://marc.theaimsgroup.com/?l=linux-kernel&m=113018709002036&w=2 We noticed that notifier chains in the kernel fall into two basic usage classes: "Blocking" chains are always called from a process context and the callout routines are allowed to sleep; "Atomic" chains can be called from an atomic context and the callout routines are not allowed to sleep. We decided to codify this distinction and make it part of the API. Therefore this set of patches introduces three new, parallel APIs: one for blocking notifiers, one for atomic notifiers, and one for "raw" notifiers (which is really just the old API under a new name). New kinds of data structures are used for the heads of the chains, and new routines are defined for registration, unregistration, and calling a chain. The three APIs are explained in include/linux/notifier.h and their implementation is in kernel/sys.c. With atomic and blocking chains, the implementation guarantees that the chain links will not be corrupted and that chain callers will not get messed up by entries being added or removed. For raw chains the implementation provides no guarantees at all; users of this API must provide their own protections. (The idea was that situations may come up where the assumptions of the atomic and blocking APIs are not appropriate, so it should be possible for users to handle these things in their own way.) There are some limitations, which should not be too hard to live with. For atomic/blocking chains, registration and unregistration must always be done in a process context since the chain is protected by a mutex/rwsem. Also, a callout routine for a non-raw chain must not try to register or unregister entries on its own chain. (This did happen in a couple of places and the code had to be changed to avoid it.) Since atomic chains may be called from within an NMI handler, they cannot use spinlocks for synchronization. Instead we use RCU. The overhead falls almost entirely in the unregister routine, which is okay since unregistration is much less frequent that calling a chain. Here is the list of chains that we adjusted and their classifications. None of them use the raw API, so for the moment it is only a placeholder. ATOMIC CHAINS ------------- arch/i386/kernel/traps.c: i386die_chain arch/ia64/kernel/traps.c: ia64die_chain arch/powerpc/kernel/traps.c: powerpc_die_chain arch/sparc64/kernel/traps.c: sparc64die_chain arch/x86_64/kernel/traps.c: die_chain drivers/char/ipmi/ipmi_si_intf.c: xaction_notifier_list kernel/panic.c: panic_notifier_list kernel/profile.c: task_free_notifier net/bluetooth/hci_core.c: hci_notifier net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_chain net/ipv4/netfilter/ip_conntrack_core.c: ip_conntrack_expect_chain net/ipv6/addrconf.c: inet6addr_chain net/netfilter/nf_conntrack_core.c: nf_conntrack_chain net/netfilter/nf_conntrack_core.c: nf_conntrack_expect_chain net/netlink/af_netlink.c: netlink_chain BLOCKING CHAINS --------------- arch/powerpc/platforms/pseries/reconfig.c: pSeries_reconfig_chain arch/s390/kernel/process.c: idle_chain arch/x86_64/kernel/process.c idle_notifier drivers/base/memory.c: memory_chain drivers/cpufreq/cpufreq.c cpufreq_policy_notifier_list drivers/cpufreq/cpufreq.c cpufreq_transition_notifier_list drivers/macintosh/adb.c: adb_client_list drivers/macintosh/via-pmu.c sleep_notifier_list drivers/macintosh/via-pmu68k.c sleep_notifier_list drivers/macintosh/windfarm_core.c wf_client_list drivers/usb/core/notify.c usb_notifier_list drivers/video/fbmem.c fb_notifier_list kernel/cpu.c cpu_chain kernel/module.c module_notify_list kernel/profile.c munmap_notifier kernel/profile.c task_exit_notifier kernel/sys.c reboot_notifier_list net/core/dev.c netdev_chain net/decnet/dn_dev.c: dnaddr_chain net/ipv4/devinet.c: inetaddr_chain It's possible that some of these classifications are wrong. If they are, please let us know or submit a patch to fix them. Note that any chain that gets called very frequently should be atomic, because the rwsem read-locking used for blocking chains is very likely to incur cache misses on SMP systems. (However, if the chain's callout routines may sleep then the chain cannot be atomic.) The patch set was written by Alan Stern and Chandra Seetharaman, incorporating material written by Keith Owens and suggestions from Paul McKenney and Andrew Morton. [jes@sgi.com: restructure the notifier chain initialization macros] Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Chandra Seetharaman <sekharan@us.ibm.com> Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-20[IPV6]: Cleanups for net/ipv6/addrconf.c (kzalloc, early exit) v2Ingo Oeser
Here are some possible (and trivial) cleanups. - use kzalloc() where possible - invert allocation failure test like if (object) { /* Rest of function here */ } to if (object == NULL) return NULL; /* Rest of function here */ Signed-off-by: Ingo Oeser <ioe-lkml@rameria.de> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ROUTE: Add accept_ra_rt_info_max_plen sysctl.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ROUTE: Add router_probe_interval sysctl.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ROUTE: Add accept_ra_rtr_pref sysctl.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ADDRCONF: Add accept_ra_pinfo sysctl.YOSHIFUJI Hideaki
This controls whether we accept Prefix Information in RAs. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ROUTE: Add accept_ra_defrtr sysctl.YOSHIFUJI Hideaki
This controls whether we accept default router information in RAs. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ADDRCONF: Split up ipv6_generate_eui64() by device type.YOSHIFUJI Hideaki
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: ADDRCONF: Use our standard algorithm for randomized ifid.YOSHIFUJI Hideaki
RFC 3041 describes an algorithm to generate random interface identifier. In RFC 3041bis, it is allowed to use different algorithm than one described in RFC 3041. So, let's use our standard pseudo random algorithm to simplify our implementation. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-20[IPV6]: TUNNEL6: Don't try to add multicast route twice.YOSHIFUJI Hideaki
Since addrconf_add_dev() has already called addrconf_add_mroute() to added route for multicast prefix, there's no point to call it again in addrconf_ip6_tnl_config(). Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-11[IPV6]: fix ipv6_saddr_score struct elementBrian Haley
The scope element in the ipv6_saddr_score struct used in ipv6_dev_get_saddr() is an unsigned integer, but __ipv6_addr_src_scope() returns a signed integer (and can return -1). Signed-off-by: Brian Haley <brian.haley@hp.com> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-08[IPV6]: Address autoconfiguration does not work after device down/up cycleKristian Slavov
If you set network interface down and up again, the IPv6 address autoconfiguration does not work. 'ip addr' shows that the link-local address is in tentative state. We don't even react to periodical router advertisements. During NETDEV_DOWN we clear IF_READY, and we don't set it back in NETDEV_UP. While starting to perform DAD on the link-local address, we notice that the device is not in IF_READY, and we abort autoconfiguration process (which would eventually send router solicitations). Acked-by: Juha-Matti Tapio <jmtapio@verkkotelakka.net> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-02-02[IPV6]: Don't hold extra ref count in ipv6_ifa_notifyHerbert Xu
Currently the logic in ipv6_ifa_notify is to hold an extra reference count for addrconf dst's that get added to the routing table. Thus, when addrconf dst entries are taken out of the routing table, we need to drop that dst. However, addrconf dst entries may be removed from the routing table by means other than __ipv6_ifa_notify. So we're faced with the choice of either fixing up all places where addrconf dst entries are removed, or dropping the extra reference count altogether. I chose the latter because the ifp itself always holds a dst reference count of 1 while it's alive. This is dropped just before we kfree the ifp object. Therefore we know that in __ipv6_ifa_notify we will always hold that count. This bug was found by Eric W. Biederman. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-17[IPV6]: Preserve procfs IPV6 address output formatYOSHIFUJI Hideaki
Procfs always output IPV6 addresses without the colon characters, and we cannot change that. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-13[NET]: Use NIP6_FMT in kernel.hJoe Perches
There are errors and inconsistency in the display of NIP6 strings. ie: net/ipv6/ip6_flowlabel.c There are errors and inconsistency in the display of NIPQUAD strings too. ie: net/netfilter/nf_conntrack_ftp.c This patch: adds NIP6_FMT to kernel.h changes all code to use NIP6_FMT fixes net/ipv6/ip6_flowlabel.c adds NIPQUAD_FMT to kernel.h fixes net/netfilter/nf_conntrack_ftp.c changes a few uses of "%u.%u.%u.%u" to NIPQUAD_FMT for symmetry to NIP6_FMT Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-11[PATCH] capable/capability.h (net/)Randy Dunlap
net: Use <linux/capability.h> where capable() is used. Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-07[IPV6]: small cleanupsAdrian Bunk
This patch contains the following cleanups: - addrconf.c: make addrconf_dad_stop() static - inet6_connection_sock.c should #include <net/inet6_connection_sock.h> for getting the prototypes of it's global functions Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-01-03[IPV6]: Introduce inet6_timewait_sockArnaldo Carvalho de Melo
Out of tcp6_timewait_sock, that now is just an aggregation of inet_timewait_sock and inet6_timewait_sock, using tw_ipv6_offset in struct inet_timewait_sock, that is common to the IPv6 transport protocols that use timewait sockets, like DCCP and TCP. tw_ipv6_offset plays the struct inet_sock pinfo6 role, i.e. for the generic code to find the IPv6 area in a timewait sock. Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-27[IPV6]: Fix addrconf dead lock.YOSHIFUJI Hideaki
We need to release idev->lcok before we call addrconf_dad_stop(). It calls ipv6_addr_del(), which will hold idev->lock. Bug spotted by Yasuyuki KOZAKAI <yasuyuki.kozakai@toshiba.co.jp>. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-23[IPV6]: Fix Temporary Address GenerationHiroyuki YAMAMORI
From: Hiroyuki YAMAMORI <h-yamamo@db3.so-net.ne.jp> Since regen_count is stored in the public address, we need to reset it when we start renewing temporary address. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-23[IPV6]: Fix dead lock.YOSHIFUJI Hideaki
We need to relesae ifp->lock before we call addrconf_dad_stop(), which will hold ifp->lock. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-22Merge git://git.skbuff.net/gitroot/yoshfuji/linux-2.6.14+git+ipv6-fix-20051221aDavid S. Miller
2005-12-21[IPV6]: Fix address deletionKristian Slavov
If you add more than one IPv6 address belonging to the same prefix and delete the address that was last added, routing table entry for that prefix is also deleted. Tested on 2.6.14.4 To reproduce: ip addr add 3ffe::1/64 dev eth0 ip addr add 3ffe::2/64 dev eth0 /* wait DAD */ sleep 1 ip addr del 3ffe::2/64 dev eth0 ip -6 route (route to 3ffe::/64 should be gone) In ipv6_del_addr(), if ifa == ifp, we set ifa->if_next to NULL, and later assign ifap = &ifa->if_next, effectively terminating the for-loop. This prevents us from checking if there are other addresses using the same prefix that are valid, and thus resulting in deletion of the prefix. This applies only if the first entry in idev->addr_list is the address to be deleted. Signed-off-by: Kristian Slavov <kristian.slavov@nomadiclab.com> Acked-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2005-12-21[IPV6]: Don't select a tentative address as a source address.YOSHIFUJI Hideaki
A tentative address is not considered "assigned to an interface" in the traditional sense (RFC2462 Section 4). Don't try to select such an address for the source address. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
2005-12-21[IPV6]: Run DAD when the link becomes ready.YOSHIFUJI Hideaki
If the link was not available when the interface was created, run DAD for pending tentative addresses when the link becomes ready. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>