diff options
author | Hannes Frederic Sowa <hannes@stressinduktion.org> | 2015-03-24 01:36:04 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-03-24 05:12:09 +0300 |
commit | 5f40ef77adb237954d615a76621df1b80a329b31 (patch) | |
tree | 29c69d4f196d3d7f8fa9e33b7d54ea8c48ba76e1 /net/ipv6 | |
parent | 8e8e676d0b3c7f074c719c7c05b20296b9b0b0b1 (diff) | |
download | linux-5f40ef77adb237954d615a76621df1b80a329b31.tar.xz |
ipv6: do retries on stable privacy addresses
If a DAD conflict is detected, we want to retry privacy stable address
generation up to idgen_retries (= 3) times with a delay of idgen_delay
(= 1 second). Add the logic to addrconf_dad_failure.
By design, we don't clean up dad failed permanent addresses.
Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
-rw-r--r-- | net/ipv6/addrconf.c | 57 |
1 files changed, 54 insertions, 3 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 1cc5320e510f..9b51fdb42ba9 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -1710,6 +1710,7 @@ static int addrconf_dad_end(struct inet6_ifaddr *ifp) void addrconf_dad_failure(struct inet6_ifaddr *ifp) { + struct in6_addr addr; struct inet6_dev *idev = ifp->idev; if (addrconf_dad_end(ifp)) { @@ -1720,9 +1721,59 @@ void addrconf_dad_failure(struct inet6_ifaddr *ifp) net_info_ratelimited("%s: IPv6 duplicate address %pI6c detected!\n", ifp->idev->dev->name, &ifp->addr); - if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) { - struct in6_addr addr; + spin_lock_bh(&ifp->lock); + + if (ifp->flags & IFA_F_STABLE_PRIVACY) { + int scope = ifp->scope; + u32 flags = ifp->flags; + struct in6_addr new_addr; + struct inet6_ifaddr *ifp2; + u32 valid_lft, preferred_lft; + int pfxlen = ifp->prefix_len; + const unsigned int idgen_retries = 3; + const unsigned int idgen_delay = 1 * HZ; + int retries = ifp->stable_privacy_retry + 1; + + if (retries > idgen_retries) { + net_info_ratelimited("%s: privacy stable address generation failed because of DAD conflicts!\n", + ifp->idev->dev->name); + goto errdad; + } + + new_addr = ifp->addr; + if (ipv6_generate_stable_address(&new_addr, retries, + idev)) + goto errdad; + valid_lft = ifp->valid_lft; + preferred_lft = ifp->prefered_lft; + + spin_unlock_bh(&ifp->lock); + + if (idev->cnf.max_addresses && + ipv6_count_addresses(idev) >= + idev->cnf.max_addresses) + goto lock_errdad; + + net_info_ratelimited("%s: generating new stable privacy address because of DAD conflict\n", + ifp->idev->dev->name); + + ifp2 = ipv6_add_addr(idev, &new_addr, NULL, pfxlen, + scope, flags, valid_lft, + preferred_lft); + if (IS_ERR(ifp2)) + goto lock_errdad; + + spin_lock_bh(&ifp2->lock); + ifp2->stable_privacy_retry = retries; + ifp2->state = INET6_IFADDR_STATE_PREDAD; + spin_unlock_bh(&ifp2->lock); + + addrconf_mod_dad_work(ifp2, idgen_delay); + in6_ifa_put(ifp2); +lock_errdad: + spin_lock_bh(&ifp->lock); + } else if (idev->cnf.accept_dad > 1 && !idev->cnf.disable_ipv6) { addr.s6_addr32[0] = htonl(0xfe800000); addr.s6_addr32[1] = 0; @@ -1736,7 +1787,7 @@ void addrconf_dad_failure(struct inet6_ifaddr *ifp) } } - spin_lock_bh(&ifp->lock); +errdad: /* transition from _POSTDAD to _ERRDAD */ ifp->state = INET6_IFADDR_STATE_ERRDAD; spin_unlock_bh(&ifp->lock); |