From bb4e022502dd7f76d4f1cd705a7bac628d8c098c Mon Sep 17 00:00:00 2001 From: Matus Fabian Date: Thu, 13 Sep 2018 02:36:25 -0700 Subject: NAT: TCP MSS clamping NAT plugin changes the MSS value in TCP SYN packets to avoid fragmentation. If the negotiated MSS value is greater than the configured value it is changed to the configured value. If the negotiated MSS value is smaller than the configured value it remains unchanged. Change-Id: Ic3c4f94a2f1b76e2bf79f50f3ad36a4097f3f188 Signed-off-by: Matus Fabian --- src/plugins/nat/nat_api.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) (limited to 'src/plugins/nat/nat_api.c') diff --git a/src/plugins/nat/nat_api.c b/src/plugins/nat/nat_api.c index 2994f8001f4..4c532ed7e2b 100644 --- a/src/plugins/nat/nat_api.c +++ b/src/plugins/nat/nat_api.c @@ -573,6 +573,63 @@ static void *vl_api_nat_get_addr_and_port_alloc_alg_t_print FINISH; } +static void +vl_api_nat_set_mss_clamping_t_handler (vl_api_nat_set_mss_clamping_t * mp) +{ + snat_main_t *sm = &snat_main; + vl_api_nat_set_mss_clamping_reply_t *rmp; + int rv = 0; + + if (mp->enable) + { + sm->mss_clamping = ntohs (mp->mss_value); + sm->mss_value_net = mp->mss_value; + } + else + sm->mss_clamping = 0; + + REPLY_MACRO (VL_API_NAT_SET_MSS_CLAMPING_REPLY); +} + +static void * +vl_api_nat_set_mss_clamping_t_print (vl_api_nat_set_mss_clamping_t * mp, + void *handle) +{ + u8 *s; + + s = format (0, "SCRIPT: nat_set_mss_clamping enable %d mss_value %d\n", + mp->enable, ntohs (mp->mss_value)); + + FINISH; +} + +static void +vl_api_nat_get_mss_clamping_t_handler (vl_api_nat_get_mss_clamping_t * mp) +{ + snat_main_t *sm = &snat_main; + vl_api_nat_get_mss_clamping_reply_t *rmp; + int rv = 0; + + /* *INDENT-OFF* */ + REPLY_MACRO2 (VL_API_NAT_GET_MSS_CLAMPING_REPLY, + ({ + rmp->enable = sm->mss_clamping ? 1 : 0; + rmp->mss_value = htons (sm->mss_clamping); + })) + /* *INDENT-ON* */ +} + +static void * +vl_api_nat_get_mss_clamping_t_print (vl_api_nat_get_mss_clamping_t * mp, + void *handle) +{ + u8 *s; + + s = format (0, "SCRIPT: nat_get_mss_clamping"); + + FINISH; +} + /*************/ /*** NAT44 ***/ /*************/ @@ -3083,6 +3140,8 @@ _(NAT_SET_TIMEOUTS, nat_set_timeouts) \ _(NAT_GET_TIMEOUTS, nat_get_timeouts) \ _(NAT_SET_ADDR_AND_PORT_ALLOC_ALG, nat_set_addr_and_port_alloc_alg) \ _(NAT_GET_ADDR_AND_PORT_ALLOC_ALG, nat_get_addr_and_port_alloc_alg) \ +_(NAT_SET_MSS_CLAMPING, nat_set_mss_clamping) \ +_(NAT_GET_MSS_CLAMPING, nat_get_mss_clamping) \ _(NAT44_ADD_DEL_ADDRESS_RANGE, nat44_add_del_address_range) \ _(NAT44_INTERFACE_ADD_DEL_FEATURE, nat44_interface_add_del_feature) \ _(NAT44_ADD_DEL_STATIC_MAPPING, nat44_add_del_static_mapping) \ -- cgit 1.2.3-korg