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Message-ID: <20070126191817.GC15916@hmsreliant.homelinux.net>
Date: Fri, 26 Jan 2007 14:18:17 -0500
From: Neil Horman <nhorman@...driver.com>
To: YOSHIFUJI Hideaki / 吉藤英明
<yoshfuji@...ux-ipv6.org>
Cc: vladislav.yasevich@...com, sri@...ibm.com, davem@...emloft.net,
kuznet@....inr.ac.ru, pekkas@...core.fi, jmorris@...ei.org,
kaber@...eworks.de, netdev@...r.kernel.org
Subject: Re: [PATCH] IPv6: Implement RFC 4429 Optimistic Duplicate Address Detection
On Fri, Jan 26, 2007 at 09:13:31AM +0900, YOSHIFUJI Hideaki / 吉藤英明 wrote:
> In article <20070125194500.GB8891@...reliant.homelinux.net> (at Thu, 25 Jan 2007 14:45:00 -0500), Neil Horman <nhorman@...driver.com> says:
New patch attached with most of your suggestions incorporated. I've a few
comments mixed in for some of the suggestions that I think need further
discussion
> If optimistic_dad is disabled, flags should be IFA_F_TEMPORARY,
> not IFA_F_TEMPORARY|IFA_F_OPTIMISTIC.
>
> Another idea is to use IFA_F_OPTIMISTIC not
> IFA_F_OPTIMISTIC|IFA_F_TENTATIVE until the DAD has been finished.
>
I'm currently setting the OPTIMISTIC flag in every location that its possibly
needed, and then clearing it in addrconf_dad_start if that interface is not
participating in optimistic dad. I do this because the RFC in section 3.1
indicates that manually configured addresses should not set the optimistic flag.
If I removed the OPTIMISTIC flag from the locations it gets set in the patch and
then only set it for participating interfaces in addrconf_dad_start, I would
need to have some way to tell if the address in question was manually configured
(to avoid setting it in that case). At present I see no clear way to do that,
but if you have a suggestion, I'll happily change this around.
<snip>
>
> ((ifa_result->flags & (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC)) == 0)
<snip>
> ditto.
>
Done
> > @@ -2123,7 +2133,8 @@ static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr
> > {
> > struct inet6_ifaddr * ifp;
> >
> > - ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, IFA_F_PERMANENT);
> > + ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK,
> > + IFA_F_PERMANENT|IFA_F_OPTIMISTIC);
> > if (!IS_ERR(ifp)) {
> > addrconf_dad_start(ifp, 0);
> > in6_ifa_put(ifp);
>
> Please do not always put IFA_F_OPTIMISTIC.
>
Again, same reasoning as above for why I set optimistic in this way.
> >
> > + /*
> > + * Optimistic nodes need to joing the anycast address
> > + * right away
> > + */
> > + if (ifp->flags & IFA_F_OPTIMISTIC)
> > + addrconf_join_anycast(ifp);
> > +
> > if (ifp->prefix_len != 128 && (ifp->flags&IFA_F_PERMANENT))
> > addrconf_prefix_route(&ifp->addr, ifp->prefix_len, dev, 0,
> > flags);
>
> Should we join anycast even if the node is a host (not a router)?!
>
I've moved this to the spot below where we check if we are forwarding, so the
new patch attached does not join anycast if we are a router.
> When you add a call to "addrconf_join_anycast()",
> you must consider when to leave this.
>
I think addrconf_dad_completed is appropriate for this. New patch leaves
anycast group when we are no longer optimistic
>
> > @@ -2573,6 +2594,18 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
> > addrconf_dad_stop(ifp);
> > return;
> > }
> > +
> > + /*
> > + * Forwarding devices (routers) should not use
> > + * optimistic addresses
> > + * Nor should interfaces that don't know the
> > + * Source address for their default gateway
> > + * RFC 4429 Sec 3.3
> > + */
> > + if ((ipv6_devconf.forwarding) ||
> > + (ifp->rt == NULL))
> > + ifp->flags &= ~IFA_F_OPTIMISTIC;
> > +
> > addrconf_dad_kick(ifp);
> > spin_unlock_bh(&ifp->lock);
> > out:
>
> Please test this condition when you are adding the
> address.
>
Are you sure? There are several locations where we add an address that we start
dad on. Shall I test this in all of those places? It would seem more
appropriate to do it in addrconf_dad_start, as I do. Or am I missing something?
> BTW, you have not implemented the later condition,
> right? Sefault gatewa is not tested.
>
I thought I was testing it. I was under the impression from my reading of the
code the ifp->rt held the rt6_info pointer for the default gateway, so if its
not set, we don't know the default gateway. I may well be missing something
here though. Please let me know.
> > index 6a9f616..fcd22e3 100644
> > --- a/net/ipv6/ndisc.c
> > +++ b/net/ipv6/ndisc.c
> > @@ -498,7 +498,21 @@ static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
> > msg->icmph.icmp6_unused = 0;
> > msg->icmph.icmp6_router = router;
> > msg->icmph.icmp6_solicited = solicited;
> > - msg->icmph.icmp6_override = override;
> > + if (!ifp || !(ifp->flags & IFA_F_OPTIMISTIC))
> > + msg->icmph.icmp6_override = override;
> > + else {
> > + /*
> > + * We must clear the override flag on all
> > + * neighbor advertisements from source
> > + * addresses that are OPTIMISTIC - RFC 4429
> > + * section 2.2
> > + */
> > + if (override)
> > + printk(KERN_WARNING
> > + "Disallowing override flag for OPTIMISTIC addr\n");
> > + msg->icmph.icmp6_override = 0;
> > + }
> > +
>
> Ifp is already put. Please clear "override" in the code
> where we try getting temporary source address for NS.
>
Done. I've moved the check to before the in6_ifa_put, and added a flag to skip
adding the sllao option if we find we are optimistic.
> > @@ -622,9 +637,20 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
> > + /*
> > + * Check the source address. If its OPTIMISTIC
> > + * and addr_len is non-zero (implying the sllao option)
> > + * then don't send the RS (RFC 4429, section 2.2)
> > + */
> > + ifp = ipv6_get_ifaddr(saddr, dev, 1);
> > +
> > + if ((!ifp) || ((ifp->flags & IFA_F_OPTIMISTIC) && dev->addr_len))
> > + return;
> > +
> > ndisc_flow_init(&fl, NDISC_ROUTER_SOLICITATION, saddr, daddr,
> > dev->ifindex);
> >
>
> I disagree. Please send RS in other way.
> Choose another address, or send it without SLLAO.
>
Done
More thoughts/comments appreciated.
Thanks & Regards
Neil
Signed-off-by: Neil Horman <nhorman@...driver.com>
include/linux/if_addr.h | 1
include/linux/ipv6.h | 2 +
include/linux/sysctl.h | 1
include/net/addrconf.h | 4 +-
net/ipv6/addrconf.c | 78 +++++++++++++++++++++++++++++++++++++++---------
net/ipv6/mcast.c | 4 +-
net/ipv6/ndisc.c | 74 +++++++++++++++++++++++++++++++--------------
7 files changed, 124 insertions(+), 40 deletions(-)
diff --git a/include/linux/if_addr.h b/include/linux/if_addr.h
index d557e4c..43f3bed 100644
--- a/include/linux/if_addr.h
+++ b/include/linux/if_addr.h
@@ -39,6 +39,7 @@ enum
#define IFA_F_TEMPORARY IFA_F_SECONDARY
#define IFA_F_NODAD 0x02
+#define IFA_F_OPTIMISTIC 0x04
#define IFA_F_HOMEADDRESS 0x10
#define IFA_F_DEPRECATED 0x20
#define IFA_F_TENTATIVE 0x40
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index f824113..5d37abf 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -177,6 +177,7 @@ struct ipv6_devconf {
#endif
#endif
__s32 proxy_ndp;
+ __s32 optimistic_dad;
void *sysctl;
};
@@ -205,6 +206,7 @@ enum {
DEVCONF_RTR_PROBE_INTERVAL,
DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN,
DEVCONF_PROXY_NDP,
+ DEVCONF_OPTIMISTIC_DAD,
DEVCONF_MAX
};
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 81480e6..972a33a 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -570,6 +570,7 @@ enum {
NET_IPV6_RTR_PROBE_INTERVAL=21,
NET_IPV6_ACCEPT_RA_RT_INFO_MAX_PLEN=22,
NET_IPV6_PROXY_NDP=23,
+ NET_IPV6_OPTIMISTIC_DAD=24,
__NET_IPV6_MAX
};
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 88df8fc..d248a19 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -73,7 +73,9 @@ extern int ipv6_get_saddr(struct dst_entry *dst,
extern int ipv6_dev_get_saddr(struct net_device *dev,
struct in6_addr *daddr,
struct in6_addr *saddr);
-extern int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *);
+extern int ipv6_get_lladdr(struct net_device *dev,
+ struct in6_addr *,
+ unsigned char banned_flags);
extern int ipv6_rcv_saddr_equal(const struct sock *sk,
const struct sock *sk2);
extern void addrconf_join_solict(struct net_device *dev,
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 2a7e461..fc29815 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -830,7 +830,8 @@ retry:
ift = !max_addresses ||
ipv6_count_addresses(idev) < max_addresses ?
ipv6_add_addr(idev, &addr, tmp_plen,
- ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK, IFA_F_TEMPORARY) : NULL;
+ ipv6_addr_type(&addr)&IPV6_ADDR_SCOPE_MASK,
+ IFA_F_TEMPORARY|IFA_F_OPTIMISTIC) : NULL;
if (!ift || IS_ERR(ift)) {
in6_ifa_put(ifp);
in6_dev_put(idev);
@@ -962,13 +963,14 @@ int ipv6_dev_get_saddr(struct net_device *daddr_dev,
* - Tentative Address (RFC2462 section 5.4)
* - A tentative address is not considered
* "assigned to an interface" in the traditional
- * sense.
+ * sense, unless it is also flagged as optimistic.
* - Candidate Source Address (section 4)
* - In any case, anycast addresses, multicast
* addresses, and the unspecified address MUST
* NOT be included in a candidate set.
*/
- if (ifa->flags & IFA_F_TENTATIVE)
+ if ((ifa->flags & IFA_F_TENTATIVE) &&
+ (!(ifa->flags & IFA_F_OPTIMISTIC)))
continue;
if (unlikely(score.addr_type == IPV6_ADDR_ANY ||
score.addr_type & IPV6_ADDR_MULTICAST)) {
@@ -1027,15 +1029,17 @@ int ipv6_dev_get_saddr(struct net_device *daddr_dev,
}
}
- /* Rule 3: Avoid deprecated address */
+ /* Rule 3: Avoid deprecated and optimistic address */
if (hiscore.rule < 3) {
if (ipv6_saddr_preferred(hiscore.addr_type) ||
- !(ifa_result->flags & IFA_F_DEPRECATED))
+ ((ifa_result->flags &
+ (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC) == 0)))
hiscore.attrs |= IPV6_SADDR_SCORE_PREFERRED;
hiscore.rule++;
}
if (ipv6_saddr_preferred(score.addr_type) ||
- !(ifa->flags & IFA_F_DEPRECATED)) {
+ ((ifa_result->flags &
+ (IFA_F_DEPRECATED|IFA_F_OPTIMISTIC) == 0))) {
score.attrs |= IPV6_SADDR_SCORE_PREFERRED;
if (!(hiscore.attrs & IPV6_SADDR_SCORE_PREFERRED)) {
score.rule = 3;
@@ -1174,7 +1178,8 @@ int ipv6_get_saddr(struct dst_entry *dst,
}
-int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr)
+int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr,
+ unsigned char banned_flags)
{
struct inet6_dev *idev;
int err = -EADDRNOTAVAIL;
@@ -1185,7 +1190,7 @@ int ipv6_get_lladdr(struct net_device *dev, struct in6_addr *addr)
read_lock_bh(&idev->lock);
for (ifp=idev->addr_list; ifp; ifp=ifp->if_next) {
- if (ifp->scope == IFA_LINK && !(ifp->flags&IFA_F_TENTATIVE)) {
+ if (ifp->scope == IFA_LINK && !(ifp->flags & banned_flags)) {
ipv6_addr_copy(addr, &ifp->addr);
err = 0;
break;
@@ -1751,6 +1756,7 @@ ok:
update_lft = create = 1;
ifp->cstamp = jiffies;
+ ifp->flags |= IFA_F_OPTIMISTIC;
addrconf_dad_start(ifp, RTF_ADDRCONF|RTF_PREFIX_RT);
}
@@ -1945,7 +1951,11 @@ static int inet6_addr_add(int ifindex, struct in6_addr *pfx, int plen,
ifp->prefered_lft = prefered_lft;
ifp->tstamp = jiffies;
spin_unlock_bh(&ifp->lock);
-
+ /*
+ * Note that section 3.1 of RFC 4429 indicates
+ * That the Optimistic flag should not be set for
+ * manually configured addresses
+ */
addrconf_dad_start(ifp, 0);
in6_ifa_put(ifp);
addrconf_verify(0);
@@ -2123,7 +2133,8 @@ static void addrconf_add_linklocal(struct inet6_dev *idev, struct in6_addr *addr
{
struct inet6_ifaddr * ifp;
- ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK, IFA_F_PERMANENT);
+ ifp = ipv6_add_addr(idev, addr, 64, IFA_LINK,
+ IFA_F_PERMANENT|IFA_F_OPTIMISTIC);
if (!IS_ERR(ifp)) {
addrconf_dad_start(ifp, 0);
in6_ifa_put(ifp);
@@ -2190,7 +2201,7 @@ ipv6_inherit_linklocal(struct inet6_dev *idev, struct net_device *link_dev)
{
struct in6_addr lladdr;
- if (!ipv6_get_lladdr(link_dev, &lladdr)) {
+ if (!ipv6_get_lladdr(link_dev, &lladdr, IFA_F_TENTATIVE)) {
addrconf_add_linklocal(idev, &lladdr);
return 0;
}
@@ -2527,7 +2538,11 @@ static void addrconf_dad_kick(struct inet6_ifaddr *ifp)
unsigned long rand_num;
struct inet6_dev *idev = ifp->idev;
- rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
+ if (ifp->flags & IFA_F_OPTIMISTIC)
+ rand_num = 0;
+ else
+ rand_num = net_random() % (idev->cnf.rtr_solicit_delay ? : 1);
+
ifp->probes = idev->cnf.dad_transmits;
addrconf_mod_timer(ifp, AC_DAD, rand_num);
}
@@ -2537,6 +2552,9 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
struct inet6_dev *idev = ifp->idev;
struct net_device *dev = idev->dev;
+ if (!idev->cnf.optimistic_dad)
+ ifp->flags &= ~IFA_F_OPTIMISTIC;
+
addrconf_join_solict(dev, &ifp->addr);
if (ifp->prefix_len != 128 && (ifp->flags&IFA_F_PERMANENT))
@@ -2553,7 +2571,7 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
if (dev->flags&(IFF_NOARP|IFF_LOOPBACK) ||
!(ifp->flags&IFA_F_TENTATIVE) ||
ifp->flags & IFA_F_NODAD) {
- ifp->flags &= ~IFA_F_TENTATIVE;
+ ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC);
spin_unlock_bh(&ifp->lock);
read_unlock_bh(&idev->lock);
@@ -2573,6 +2591,25 @@ static void addrconf_dad_start(struct inet6_ifaddr *ifp, u32 flags)
addrconf_dad_stop(ifp);
return;
}
+
+ /*
+ * Forwarding devices (routers) should not use
+ * optimistic addresses
+ * Nor should interfaces that don't know the
+ * Source address for their default gateway
+ * RFC 4429 Sec 3.3
+ */
+ if ((ipv6_devconf.forwarding) ||
+ (ifp->rt == NULL))
+ ifp->flags &= ~IFA_F_OPTIMISTIC;
+
+ /*
+ * Optimistic nodes need to join the anycast address
+ * right away
+ */
+ if (ifp->flags & IFA_F_OPTIMISTIC)
+ addrconf_join_anycast(ifp);
+
addrconf_dad_kick(ifp);
spin_unlock_bh(&ifp->lock);
out:
@@ -2597,7 +2634,7 @@ static void addrconf_dad_timer(unsigned long data)
* DAD was successful
*/
- ifp->flags &= ~IFA_F_TENTATIVE;
+ ifp->flags &= ~(IFA_F_TENTATIVE|IFA_F_OPTIMISTIC);
spin_unlock_bh(&ifp->lock);
read_unlock_bh(&idev->lock);
@@ -2627,6 +2664,9 @@ static void addrconf_dad_completed(struct inet6_ifaddr *ifp)
* Configure the address for reception. Now it is valid.
*/
+ if (ifp->flags & IFA_F_OPTIMISTIC)
+ addrconf_leave_anycast(ifp);
+
ipv6_ifa_notify(RTM_NEWADDR, ifp);
/* If added prefix is link local and forwarding is off,
@@ -3398,6 +3438,7 @@ static void inline ipv6_store_devconf(struct ipv6_devconf *cnf,
#endif
#endif
array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
+ array[DEVCONF_OPTIMISTIC_DAD] = cnf->optimistic_dad;
}
static inline size_t inet6_if_nlmsg_size(void)
@@ -3918,6 +3959,15 @@ static struct addrconf_sysctl_table
.proc_handler = &proc_dointvec,
},
{
+ .ctl_name = NET_IPV6_OPTIMISTIC_DAD,
+ .procname = "optimistic_dad",
+ .data = &ipv6_devconf.optimistic_dad,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+
+ },
+ {
.ctl_name = 0, /* sentinel */
}
},
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 882cde4..9c5273c 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1411,7 +1411,7 @@ static struct sk_buff *mld_newpack(struct net_device *dev, int size)
skb_reserve(skb, LL_RESERVED_SPACE(dev));
- if (ipv6_get_lladdr(dev, &addr_buf)) {
+ if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
/* <draft-ietf-magma-mld-source-05.txt>:
* use unspecified address as the source address
* when a valid link-local address is not available.
@@ -1789,7 +1789,7 @@ static void igmp6_send(struct in6_addr *addr, struct net_device *dev, int type)
skb_reserve(skb, LL_RESERVED_SPACE(dev));
- if (ipv6_get_lladdr(dev, &addr_buf)) {
+ if (ipv6_get_lladdr(dev, &addr_buf, IFA_F_TENTATIVE)) {
/* <draft-ietf-magma-mld-source-05.txt>:
* use unspecified address as the source address
* when a valid link-local address is not available.
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index 6a9f616..6ed0357 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -447,6 +447,8 @@ static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
ifp = ipv6_get_ifaddr(solicited_addr, dev, 1);
if (ifp) {
src_addr = solicited_addr;
+ if (ifp->flags & IFA_F_OPTIMISTIC)
+ override = 0;
in6_ifa_put(ifp);
} else {
if (ipv6_dev_get_saddr(dev, daddr, &tmpaddr))
@@ -498,7 +500,8 @@ static void ndisc_send_na(struct net_device *dev, struct neighbour *neigh,
msg->icmph.icmp6_unused = 0;
msg->icmph.icmp6_router = router;
msg->icmph.icmp6_solicited = solicited;
- msg->icmph.icmp6_override = override;
+ msg->icmph.icmp6_override = override;
+
/* Set the target address. */
ipv6_addr_copy(&msg->target, solicited_addr);
@@ -542,7 +545,8 @@ void ndisc_send_ns(struct net_device *dev, struct neighbour *neigh,
int send_llinfo;
if (saddr == NULL) {
- if (ipv6_get_lladdr(dev, &addr_buf))
+ if (ipv6_get_lladdr(dev, &addr_buf,
+ (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)))
return;
saddr = &addr_buf;
}
@@ -622,9 +626,21 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
struct sk_buff *skb;
struct icmp6hdr *hdr;
__u8 * opt;
+ struct inet6_ifaddr *ifp;
+ int include_sllao_option = 1;
int len;
int err;
+ /*
+ * Check the source address. If its OPTIMISTIC
+ * and addr_len is non-zero (implying the sllao option)
+ * then don't send the RS (RFC 4429, section 2.2)
+ */
+ ifp = ipv6_get_ifaddr(saddr, dev, 1);
+
+ if ((!ifp) || ((ifp->flags & IFA_F_OPTIMISTIC) && dev->addr_len))
+ include_sllao_option=0;
+
ndisc_flow_init(&fl, NDISC_ROUTER_SOLICITATION, saddr, daddr,
dev->ifindex);
@@ -664,7 +680,7 @@ void ndisc_send_rs(struct net_device *dev, struct in6_addr *saddr,
opt = (u8*) (hdr + 1);
- if (dev->addr_len)
+ if (dev->addr_len && include_sllao_option)
ndisc_fill_addr_option(opt, ND_OPT_SOURCE_LL_ADDR, dev->dev_addr,
dev->addr_len, dev->type);
@@ -746,6 +762,7 @@ static void ndisc_recv_ns(struct sk_buff *skb)
int dad = ipv6_addr_any(saddr);
int inc;
int is_router;
+ int type;
if (ipv6_addr_is_multicast(&msg->target)) {
ND_PRINTK2(KERN_WARNING
@@ -796,28 +813,39 @@ static void ndisc_recv_ns(struct sk_buff *skb)
inc = ipv6_addr_is_multicast(daddr);
if ((ifp = ipv6_get_ifaddr(&msg->target, dev, 1)) != NULL) {
- if (ifp->flags & IFA_F_TENTATIVE) {
- /* Address is tentative. If the source
- is unspecified address, it is someone
- does DAD, otherwise we ignore solicitations
- until DAD timer expires.
- */
- if (!dad)
+
+ if (ifp->flags & (IFA_F_TENTATIVE|IFA_F_OPTIMISTIC)) {
+ if (dad) {
+ if (dev->type == ARPHRD_IEEE802_TR) {
+ unsigned char *sadr = skb->mac.raw;
+ if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
+ sadr[9] == dev->dev_addr[1] &&
+ sadr[10] == dev->dev_addr[2] &&
+ sadr[11] == dev->dev_addr[3] &&
+ sadr[12] == dev->dev_addr[4] &&
+ sadr[13] == dev->dev_addr[5]) {
+ /* looped-back to us */
+ goto out;
+ }
+ }
+
+ /*
+ * We are colliding with another node
+ * who is doing DAD
+ * so fail our DAD process
+ */
+ addrconf_dad_failure(ifp);
goto out;
- if (dev->type == ARPHRD_IEEE802_TR) {
- unsigned char *sadr = skb->mac.raw;
- if (((sadr[8] ^ dev->dev_addr[0]) & 0x7f) == 0 &&
- sadr[9] == dev->dev_addr[1] &&
- sadr[10] == dev->dev_addr[2] &&
- sadr[11] == dev->dev_addr[3] &&
- sadr[12] == dev->dev_addr[4] &&
- sadr[13] == dev->dev_addr[5]) {
- /* looped-back to us */
+ } else {
+ /*
+ * This is not a dad solicitation.
+ * If we are an optimistic node,
+ * we should respond.
+ * Otherwise, we should ignore it.
+ */
+ if (!(ifp->flags & IFA_F_OPTIMISTIC))
goto out;
- }
}
- addrconf_dad_failure(ifp);
- return;
}
idev = ifp->idev;
@@ -1406,7 +1434,7 @@ void ndisc_send_redirect(struct sk_buff *skb, struct neighbour *neigh,
dev = skb->dev;
- if (ipv6_get_lladdr(dev, &saddr_buf)) {
+ if (ipv6_get_lladdr(dev, &saddr_buf, IFA_F_TENTATIVE)) {
ND_PRINTK2(KERN_WARNING
"ICMPv6 Redirect: no link-local address on %s\n",
dev->name);
-
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