@@ -111,11 +111,6 @@ ipfrag_low_thresh - INTEGER
ipfrag_time - INTEGER
Time in seconds to keep an IP fragment in memory.
-ipfrag_secret_interval - INTEGER
- Regeneration interval (in seconds) of the hash secret (or lifetime
- for the hash secret) for IP fragments.
- Default: 600
-
ipfrag_max_dist - INTEGER
ipfrag_max_dist is a non-negative integer value which defines the
maximum "disorder" which is allowed among fragments which share a
@@ -1164,11 +1159,6 @@ ip6frag_low_thresh - INTEGER
ip6frag_time - INTEGER
Time in seconds to keep an IPv6 fragment in memory.
-ip6frag_secret_interval - INTEGER
- Regeneration interval (in seconds) of the hash secret (or lifetime
- for the hash secret) for IPv6 fragments.
- Default: 600
-
conf/default/*:
Change the interface-specific default settings.
@@ -58,11 +58,11 @@ struct inet_frags {
* Its primarily a rebuild protection rwlock.
*/
rwlock_t lock ____cacheline_aligned_in_smp;
- int secret_interval;
- struct timer_list secret_timer;
struct work_struct frags_work;
unsigned int next_bucket;
+ unsigned long last_rebuild_jiffies;
+ bool rebuild;
/* The first call to hashfn is responsible to initialize
* rnd. This is best done with net_get_random_once.
@@ -419,10 +419,12 @@ static struct ctl_table lowpan_frags_ns_ctl_table[] = {
{ }
};
+/* secret interval has been deprecated */
+static int lowpan_frags_secret_interval_unused;
static struct ctl_table lowpan_frags_ctl_table[] = {
{
.procname = "6lowpanfrag_secret_interval",
- .data = &lowpan_frags.secret_interval,
+ .data = &lowpan_frags_secret_interval_unused,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
@@ -562,7 +564,6 @@ int __init lowpan_net_frag_init(void)
lowpan_frags.qsize = sizeof(struct frag_queue);
lowpan_frags.match = lowpan_frag_match;
lowpan_frags.frag_expire = lowpan_frag_expire;
- lowpan_frags.secret_interval = 10 * 60 * HZ;
inet_frags_init(&lowpan_frags);
return ret;
@@ -28,6 +28,9 @@
#define INETFRAGS_EVICT_BUCKETS 128
#define INETFRAGS_EVICT_MAX 512
+/* don't rebuild inetfrag table with new secret more often than this */
+#define INETFRAGS_MIN_REBUILD_INTERVAL (5 * HZ)
+
/* Given the OR values of all fragments, apply RFC 3168 5.3 requirements
* Value : 0xff if frame should be dropped.
* 0 or INET_ECN_CE value, to be ORed in to final iph->tos field
@@ -55,16 +58,24 @@ inet_frag_hashfn(const struct inet_frags *f, const struct inet_frag_queue *q)
return f->hashfn(q) & (INETFRAGS_HASHSZ - 1);
}
-static void inet_frag_secret_rebuild(unsigned long dummy)
+static bool inet_frag_may_rebuild(struct inet_frags *f)
+{
+ return time_after(jiffies,
+ f->last_rebuild_jiffies + INETFRAGS_MIN_REBUILD_INTERVAL);
+}
+
+static void inet_frag_secret_rebuild(struct inet_frags *f)
{
- struct inet_frags *f = (struct inet_frags *)dummy;
- unsigned long now = jiffies;
int i;
/* Per bucket lock NOT needed here, due to write lock protection */
- write_lock(&f->lock);
+ write_lock_bh(&f->lock);
+
+ if (!inet_frag_may_rebuild(f))
+ goto out;
get_random_bytes(&f->rnd, sizeof(u32));
+
for (i = 0; i < INETFRAGS_HASHSZ; i++) {
struct inet_frag_bucket *hb;
struct inet_frag_queue *q;
@@ -85,9 +96,11 @@ static void inet_frag_secret_rebuild(unsigned long dummy)
}
}
}
- write_unlock(&f->lock);
- mod_timer(&f->secret_timer, now + f->secret_interval);
+ f->rebuild = false;
+ f->last_rebuild_jiffies = jiffies;
+out:
+ write_unlock_bh(&f->lock);
}
static bool inet_fragq_should_evict(const struct inet_frag_queue *q)
@@ -162,6 +175,8 @@ static void inet_frag_worker(struct work_struct *work)
f->next_bucket = i;
read_unlock_bh(&f->lock);
+ if (f->rebuild && inet_frag_may_rebuild(f))
+ inet_frag_secret_rebuild(f);
}
static void inet_frag_schedule_worker(struct inet_frags *f)
@@ -183,11 +198,7 @@ void inet_frags_init(struct inet_frags *f)
INIT_HLIST_HEAD(&hb->chain);
}
rwlock_init(&f->lock);
-
- setup_timer(&f->secret_timer, inet_frag_secret_rebuild,
- (unsigned long)f);
- f->secret_timer.expires = jiffies + f->secret_interval;
- add_timer(&f->secret_timer);
+ f->last_rebuild_jiffies = 0;
}
EXPORT_SYMBOL(inet_frags_init);
@@ -199,7 +210,6 @@ EXPORT_SYMBOL(inet_frags_init_net);
void inet_frags_fini(struct inet_frags *f)
{
- del_timer(&f->secret_timer);
cancel_work_sync(&f->frags_work);
}
EXPORT_SYMBOL(inet_frags_fini);
@@ -399,8 +409,13 @@ struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
if (depth <= INETFRAGS_MAXDEPTH)
return inet_frag_create(nf, f, key);
- else
- return ERR_PTR(-ENOBUFS);
+
+ if (inet_frag_may_rebuild(f)) {
+ f->rebuild = true;
+ inet_frag_schedule_worker(f);
+ }
+
+ return ERR_PTR(-ENOBUFS);
}
EXPORT_SYMBOL(inet_frag_find);
@@ -720,10 +720,12 @@ static struct ctl_table ip4_frags_ns_ctl_table[] = {
{ }
};
+/* secret interval has been deprecated */
+static int ip4_frags_secret_interval_unused;
static struct ctl_table ip4_frags_ctl_table[] = {
{
.procname = "ipfrag_secret_interval",
- .data = &ip4_frags.secret_interval,
+ .data = &ip4_frags_secret_interval_unused,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
@@ -853,6 +855,5 @@ void __init ipfrag_init(void)
ip4_frags.qsize = sizeof(struct ipq);
ip4_frags.match = ip4_frag_match;
ip4_frags.frag_expire = ip_expire;
- ip4_frags.secret_interval = 10 * 60 * HZ;
inet_frags_init(&ip4_frags);
}
@@ -669,7 +669,6 @@ int nf_ct_frag6_init(void)
nf_frags.qsize = sizeof(struct frag_queue);
nf_frags.match = ip6_frag_match;
nf_frags.frag_expire = nf_ct_frag6_expire;
- nf_frags.secret_interval = 10 * 60 * HZ;
inet_frags_init(&nf_frags);
ret = register_pernet_subsys(&nf_ct_net_ops);
@@ -604,10 +604,12 @@ static struct ctl_table ip6_frags_ns_ctl_table[] = {
{ }
};
+/* secret interval has been deprecated */
+static int ip6_frags_secret_interval_unused;
static struct ctl_table ip6_frags_ctl_table[] = {
{
.procname = "ip6frag_secret_interval",
- .data = &ip6_frags.secret_interval,
+ .data = &ip6_frags_secret_interval_unused,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec_jiffies,
@@ -737,7 +739,6 @@ int __init ipv6_frag_init(void)
ip6_frags.qsize = sizeof(struct frag_queue);
ip6_frags.match = ip6_frag_match;
ip6_frags.frag_expire = ip6_frag_expire;
- ip6_frags.secret_interval = 10 * 60 * HZ;
inet_frags_init(&ip6_frags);
out:
return ret;