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@xxxxxxxxx> Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx> --- 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(+) diff --git a/Documentation/networking/ip-sysctl.rst b/Documentation/networking/ip-sysctl.rst index b0436d3a4f11..8bff728b3a1e 100644 --- a/Documentation/networking/ip-sysctl.rst +++ b/Documentation/networking/ip-sysctl.rst @@ -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/*`` ======================== diff --git a/include/net/netns/sctp.h b/include/net/netns/sctp.h index a0f315effa94..40240722cdca 100644 --- a/include/net/netns/sctp.h +++ b/include/net/netns/sctp.h @@ -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 diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h index 14a0d22c9113..449cf9cb428b 100644 --- a/include/net/sctp/constants.h +++ b/include/net/sctp/constants.h @@ -424,4 +424,6 @@ enum { */ #define SCTP_AUTH_RANDOM_LENGTH 32 +#define SCTP_PROBE_TIMER_MIN 5000 + #endif /* __sctp_constants_h__ */ diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h index 1aa585216f34..bf5d22deaefb 100644 --- a/include/net/sctp/structs.h +++ b/include/net/sctp/structs.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; diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 336df4b36655..e01895edd3a4 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -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; diff --git a/net/sctp/socket.c b/net/sctp/socket.c index a79d193ff872..d2960ab665a5 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -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 diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index 55871b277f47..b46a416787ec 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -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; -- 2.27.0