@@ -2834,6 +2834,14 @@ encap_port - INTEGER
Default: 0
+plpmtud_probe_interval - INTEGER
+ The time interval (in milliseconds) for sending PLPMTUD probe chunks.
+ These chunks are sent at the specified interval with a variable size
+ to probe the mtu of a given path between 2 endpoints. PLPMTUD will
+ be disabled when 0 is set, and other values for it must be >= 5000.
+
+ Default: 0
+
``/proc/sys/net/core/*``
========================
@@ -84,6 +84,9 @@ struct netns_sctp {
/* HB.interval - 30 seconds */
unsigned int hb_interval;
+ /* The interval for PLPMTUD probe timer */
+ unsigned int probe_interval;
+
/* Association.Max.Retrans - 10 attempts
* Path.Max.Retrans - 5 attempts (per destination address)
* Max.Init.Retransmits - 8 attempts
@@ -424,4 +424,6 @@ enum {
*/
#define SCTP_AUTH_RANDOM_LENGTH 32
+#define SCTP_PROBE_TIMER_MIN 5000
+
#endif /* __sctp_constants_h__ */
@@ -177,6 +177,7 @@ struct sctp_sock {
* will be inherited by all new associations.
*/
__u32 hbinterval;
+ __u32 probe_interval;
__be16 udp_port;
__be16 encap_port;
@@ -858,6 +859,7 @@ struct sctp_transport {
* the destination address every heartbeat interval.
*/
unsigned long hbinterval;
+ unsigned long probe_interval;
/* SACK delay timeout */
unsigned long sackdelay;
@@ -1795,6 +1797,7 @@ struct sctp_association {
* will be inherited by all new transports.
*/
unsigned long hbinterval;
+ unsigned long probe_interval;
__be16 encap_port;
@@ -98,6 +98,7 @@ static struct sctp_association *sctp_association_init(
* sock configured value.
*/
asoc->hbinterval = msecs_to_jiffies(sp->hbinterval);
+ asoc->probe_interval = msecs_to_jiffies(sp->probe_interval);
asoc->encap_port = sp->encap_port;
@@ -625,6 +626,7 @@ struct sctp_transport *sctp_assoc_add_peer(struct sctp_association *asoc,
* association configured value.
*/
peer->hbinterval = asoc->hbinterval;
+ peer->probe_interval = asoc->probe_interval;
peer->encap_port = asoc->encap_port;
@@ -4989,6 +4989,7 @@ static int sctp_init_sock(struct sock *sk)
atomic_set(&sp->pd_mode, 0);
skb_queue_head_init(&sp->pd_lobby);
sp->frag_interleave = 0;
+ sp->probe_interval = net->sctp.probe_interval;
/* Create a per socket endpoint structure. Even if we
* change the data structure relationships, this may still
@@ -55,6 +55,8 @@ static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos);
static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
void *buffer, size_t *lenp, loff_t *ppos);
+static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos);
static struct ctl_table sctp_table[] = {
{
@@ -293,6 +295,13 @@ static struct ctl_table sctp_net_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec,
},
+ {
+ .procname = "plpmtud_probe_interval",
+ .data = &init_net.sctp.probe_interval,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = proc_sctp_do_probe_interval,
+ },
{
.procname = "udp_port",
.data = &init_net.sctp.udp_port,
@@ -539,6 +548,32 @@ static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
return ret;
}
+static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
+ void *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct ctl_table tbl;
+ int ret, new_value;
+
+ memset(&tbl, 0, sizeof(struct ctl_table));
+ tbl.maxlen = sizeof(unsigned int);
+
+ if (write)
+ tbl.data = &new_value;
+ else
+ tbl.data = &net->sctp.probe_interval;
+
+ ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
+ if (write && ret == 0) {
+ if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
+ return -EINVAL;
+
+ net->sctp.probe_interval = new_value;
+ }
+
+ return ret;
+}
+
int sctp_sysctl_net_register(struct net *net)
{
struct ctl_table *table;
PLPMTUD can be enabled by doing 'sysctl -w net.sctp.probe_interval=n'. 'n' is the interval for PLPMTUD probe timer in milliseconds, and it can't be less than 5000 if it's not 0. All asoc/transport's PLPMTUD in a new socket will be enabled by default. Signed-off-by: Xin Long <lucien.xin@gmail.com> --- Documentation/networking/ip-sysctl.rst | 8 ++++++ include/net/netns/sctp.h | 3 +++ include/net/sctp/constants.h | 2 ++ include/net/sctp/structs.h | 3 +++ net/sctp/associola.c | 2 ++ net/sctp/socket.c | 1 + net/sctp/sysctl.c | 35 ++++++++++++++++++++++++++ 7 files changed, 54 insertions(+)