diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/addrconf.c | 67 |
1 files changed, 52 insertions, 15 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 2c1ed642e3f4..d3f4b7b9cf1f 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -195,6 +195,7 @@ static struct ipv6_devconf ipv6_devconf __read_mostly = { .use_tempaddr = 0, .temp_valid_lft = TEMP_VALID_LIFETIME, .temp_prefered_lft = TEMP_PREFERRED_LIFETIME, + .regen_min_advance = REGEN_MIN_ADVANCE, .regen_max_retry = REGEN_MAX_RETRY, .max_desync_factor = MAX_DESYNC_FACTOR, .max_addresses = IPV6_MAX_ADDRESSES, @@ -257,6 +258,7 @@ static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = { .use_tempaddr = 0, .temp_valid_lft = TEMP_VALID_LIFETIME, .temp_prefered_lft = TEMP_PREFERRED_LIFETIME, + .regen_min_advance = REGEN_MIN_ADVANCE, .regen_max_retry = REGEN_MAX_RETRY, .max_desync_factor = MAX_DESYNC_FACTOR, .max_addresses = IPV6_MAX_ADDRESSES, @@ -1339,12 +1341,20 @@ out: in6_ifa_put(ifp); } +static unsigned long ipv6_get_regen_advance(struct inet6_dev *idev) +{ + return idev->cnf.regen_min_advance + idev->cnf.regen_max_retry * + idev->cnf.dad_transmits * + max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ; +} + static int ipv6_create_tempaddr(struct inet6_ifaddr *ifp, bool block) { struct inet6_dev *idev = ifp->idev; unsigned long tmp_tstamp, age; unsigned long regen_advance; unsigned long now = jiffies; + u32 if_public_preferred_lft; s32 cnf_temp_preferred_lft; struct inet6_ifaddr *ift; struct ifa6_config cfg; @@ -1380,9 +1390,7 @@ retry: age = (now - ifp->tstamp) / HZ; - regen_advance = idev->cnf.regen_max_retry * - idev->cnf.dad_transmits * - max(NEIGH_VAR(idev->nd_parms, RETRANS_TIME), HZ/100) / HZ; + regen_advance = ipv6_get_regen_advance(idev); /* recalculate max_desync_factor each time and update * idev->desync_factor if it's larger @@ -1402,11 +1410,13 @@ retry: } } + if_public_preferred_lft = ifp->prefered_lft; + memset(&cfg, 0, sizeof(cfg)); cfg.valid_lft = min_t(__u32, ifp->valid_lft, idev->cnf.temp_valid_lft + age); cfg.preferred_lft = cnf_temp_preferred_lft + age - idev->desync_factor; - cfg.preferred_lft = min_t(__u32, ifp->prefered_lft, cfg.preferred_lft); + cfg.preferred_lft = min_t(__u32, if_public_preferred_lft, cfg.preferred_lft); cfg.preferred_lft = min_t(__u32, cfg.valid_lft, cfg.preferred_lft); cfg.plen = ifp->prefix_len; @@ -1415,19 +1425,41 @@ retry: write_unlock_bh(&idev->lock); - /* A temporary address is created only if this calculated Preferred - * Lifetime is greater than REGEN_ADVANCE time units. In particular, - * an implementation must not create a temporary address with a zero - * Preferred Lifetime. + /* From RFC 4941: + * + * A temporary address is created only if this calculated Preferred + * Lifetime is greater than REGEN_ADVANCE time units. In + * particular, an implementation must not create a temporary address + * with a zero Preferred Lifetime. + * + * ... + * + * When creating a temporary address, the lifetime values MUST be + * derived from the corresponding prefix as follows: + * + * ... + * + * * Its Preferred Lifetime is the lower of the Preferred Lifetime + * of the public address or TEMP_PREFERRED_LIFETIME - + * DESYNC_FACTOR. + * + * To comply with the RFC's requirements, clamp the preferred lifetime + * to a minimum of regen_advance, unless that would exceed valid_lft or + * ifp->prefered_lft. + * * Use age calculation as in addrconf_verify to avoid unnecessary * temporary addresses being generated. */ age = (now - tmp_tstamp + ADDRCONF_TIMER_FUZZ_MINUS) / HZ; if (cfg.preferred_lft <= regen_advance + age) { - in6_ifa_put(ifp); - in6_dev_put(idev); - ret = -1; - goto out; + cfg.preferred_lft = regen_advance + age + 1; + if (cfg.preferred_lft > cfg.valid_lft || + cfg.preferred_lft > if_public_preferred_lft) { + in6_ifa_put(ifp); + in6_dev_put(idev); + ret = -1; + goto out; + } } cfg.ifa_flags = IFA_F_TEMPORARY; @@ -4595,9 +4627,7 @@ restart: !ifp->regen_count && ifp->ifpub) { /* This is a non-regenerated temporary addr. */ - unsigned long regen_advance = ifp->idev->cnf.regen_max_retry * - ifp->idev->cnf.dad_transmits * - max(NEIGH_VAR(ifp->idev->nd_parms, RETRANS_TIME), HZ/100) / HZ; + unsigned long regen_advance = ipv6_get_regen_advance(ifp->idev); if (age + regen_advance >= ifp->prefered_lft) { struct inet6_ifaddr *ifpub = ifp->ifpub; @@ -6817,6 +6847,13 @@ static const struct ctl_table addrconf_sysctl[] = { .proc_handler = proc_dointvec, }, { + .procname = "regen_min_advance", + .data = &ipv6_devconf.regen_min_advance, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { .procname = "regen_max_retry", .data = &ipv6_devconf.regen_max_retry, .maxlen = sizeof(int), |