From 566178f853c1aa57be9c16007c7cca07df5d51b6 Mon Sep 17 00:00:00 2001 From: Zhu Yanjun Date: Wed, 16 Dec 2015 13:55:04 +0800 Subject: [PATCH] net: sctp: dynamically enable or disable pf state As we all know, the value of pf_retrans >= max_retrans_path can disable pf state. The variables of pf_retrans and max_retrans_path can be changed by the userspace application. Sometimes the user expects to disable pf state while the 2 variables are changed to enable pf state. So it is necessary to introduce a new variable to disable pf state. According to the suggestions from Vlad Yasevich, extra1 and extra2 are removed. The initialization of pf_enable is added. Acked-by: Vlad Yasevich Signed-off-by: Zhu Yanjun Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller --- Documentation/networking/ip-sysctl.txt | 23 ++++++++++++++++++++++- include/net/netns/sctp.h | 7 +++++++ net/sctp/protocol.c | 3 +++ net/sctp/sm_sideeffect.c | 5 ++++- net/sctp/sysctl.c | 7 +++++++ 5 files changed, 43 insertions(+), 2 deletions(-) diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 2ea4c45cf1c8..5de632ed0ec0 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -1723,6 +1723,25 @@ addip_enable - BOOLEAN Default: 0 +pf_enable - INTEGER + Enable or disable pf (pf is short for potentially failed) state. A value + of pf_retrans > path_max_retrans also disables pf state. That is, one of + both pf_enable and pf_retrans > path_max_retrans can disable pf state. + Since pf_retrans and path_max_retrans can be changed by userspace + application, sometimes user expects to disable pf state by the value of + pf_retrans > path_max_retrans, but occasionally the value of pf_retrans + or path_max_retrans is changed by the user application, this pf state is + enabled. As such, it is necessary to add this to dynamically enable + and disable pf state. See: + https://datatracker.ietf.org/doc/draft-ietf-tsvwg-sctp-failover for + details. + + 1: Enable pf. + + 0: Disable pf. + + Default: 1 + addip_noauth_enable - BOOLEAN Dynamic Address Reconfiguration (ADD-IP) requires the use of authentication to protect the operations of adding or removing new @@ -1799,7 +1818,9 @@ pf_retrans - INTEGER having to reduce path_max_retrans to a very low value. See: http://www.ietf.org/id/draft-nishida-tsvwg-sctp-failover-05.txt for details. Note also that a value of pf_retrans > path_max_retrans - disables this feature + disables this feature. Since both pf_retrans and path_max_retrans can + be changed by userspace application, a variable pf_enable is used to + disable pf state. Default: 0 diff --git a/include/net/netns/sctp.h b/include/net/netns/sctp.h index 8ba379f9e467..c501d67172b1 100644 --- a/include/net/netns/sctp.h +++ b/include/net/netns/sctp.h @@ -88,6 +88,13 @@ struct netns_sctp { */ int pf_retrans; + /* + * Disable Potentially-Failed feature, the feature is enabled by default + * pf_enable - 0 : disable pf + * - >0 : enable pf + */ + int pf_enable; + /* * Policy for preforming sctp/socket accounting * 0 - do socket level accounting, all assocs share sk_sndbuf diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c index 6c2c0accc6a0..010aced44b6b 100644 --- a/net/sctp/protocol.c +++ b/net/sctp/protocol.c @@ -1223,6 +1223,9 @@ static int __net_init sctp_defaults_init(struct net *net) /* Max.Burst - 4 */ net->sctp.max_burst = SCTP_DEFAULT_MAX_BURST; + /* Enable pf state by default */ + net->sctp.pf_enable = 1; + /* Association.Max.Retrans - 10 attempts * Path.Max.Retrans - 5 attempts (per destination address) * Max.Init.Retransmits - 8 attempts diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c index 6098d4c42fa9..05cd16400e0b 100644 --- a/net/sctp/sm_sideeffect.c +++ b/net/sctp/sm_sideeffect.c @@ -477,6 +477,8 @@ static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands, struct sctp_transport *transport, int is_hb) { + struct net *net = sock_net(asoc->base.sk); + /* The check for association's overall error counter exceeding the * threshold is done in the state function. */ @@ -503,7 +505,8 @@ static void sctp_do_8_2_transport_strike(sctp_cmd_seq_t *commands, * is SCTP_ACTIVE, then mark this transport as Partially Failed, * see SCTP Quick Failover Draft, section 5.1 */ - if ((transport->state == SCTP_ACTIVE) && + if (net->sctp.pf_enable && + (transport->state == SCTP_ACTIVE) && (asoc->pf_retrans < transport->pathmaxrxt) && (transport->error_count > asoc->pf_retrans)) { diff --git a/net/sctp/sysctl.c b/net/sctp/sysctl.c index 26d50c565f54..ccbfc93fb8fe 100644 --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -308,6 +308,13 @@ static struct ctl_table sctp_net_table[] = { .extra1 = &max_autoclose_min, .extra2 = &max_autoclose_max, }, + { + .procname = "pf_enable", + .data = &init_net.sctp.pf_enable, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, { /* sentinel */ } }; -- 2.20.1