From a3a830484fa6b6487f7f3d991a52cb6b090a8be8 Mon Sep 17 00:00:00 2001 From: Klement Sekera Date: Mon, 4 May 2020 09:56:58 +0000 Subject: nat: fix LRU blocked by inactive session This fixes a situation where long-lived inactive session blocks LRU list. Solution is to have multiple LRU lists based on session type. This helps because session timeout is same for all sessions of same type. Type: fix Signed-off-by: Klement Sekera Change-Id: I5e54b2aab73b23911d6518d42e8c3f166c69a38c --- src/plugins/nat/nat44/ed_inlines.h | 144 +++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 src/plugins/nat/nat44/ed_inlines.h (limited to 'src/plugins/nat/nat44/ed_inlines.h') diff --git a/src/plugins/nat/nat44/ed_inlines.h b/src/plugins/nat/nat44/ed_inlines.h new file mode 100644 index 00000000000..37212f36bf5 --- /dev/null +++ b/src/plugins/nat/nat44/ed_inlines.h @@ -0,0 +1,144 @@ +/* + * simple nat plugin + * + * Copyright (c) 2020 Cisco and/or its affiliates. + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at: + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef __included_ed_inlines_h__ +#define __included_ed_inlines_h__ + +#include +#include +#include +#include + +static_always_inline int +nat_ed_lru_insert (snat_main_per_thread_data_t * tsm, + snat_session_t * s, f64 now, u8 proto) +{ + dlist_elt_t *lru_list_elt; + pool_get (tsm->lru_pool, lru_list_elt); + s->lru_index = lru_list_elt - tsm->lru_pool; + switch (proto) + { + case IP_PROTOCOL_UDP: + s->lru_head_index = tsm->udp_lru_head_index; + break; + case IP_PROTOCOL_TCP: + s->lru_head_index = tsm->tcp_trans_lru_head_index; + break; + case IP_PROTOCOL_ICMP: + s->lru_head_index = tsm->icmp_lru_head_index; + break; + default: + s->lru_head_index = tsm->unk_proto_lru_head_index; + break; + } + clib_dlist_addtail (tsm->lru_pool, s->lru_head_index, s->lru_index); + lru_list_elt->value = s - tsm->sessions; + s->last_lru_update = now; + return 1; +} + +always_inline void +nat_ed_session_delete (snat_main_t * sm, snat_session_t * ses, + u32 thread_index, int lru_delete + /* delete from global LRU list */ ) +{ + snat_main_per_thread_data_t *tsm = vec_elt_at_index (sm->per_thread_data, + thread_index); + + if (lru_delete) + { + clib_dlist_remove (tsm->lru_pool, ses->lru_index); + } + pool_put_index (tsm->lru_pool, ses->lru_index); + pool_put (tsm->sessions, ses); + vlib_set_simple_counter (&sm->total_sessions, thread_index, 0, + pool_elts (tsm->sessions)); + +} + +static_always_inline int +nat_lru_free_one_with_head (snat_main_t * sm, int thread_index, + f64 now, u32 head_index) +{ + snat_session_t *s = NULL; + dlist_elt_t *oldest_elt; + f64 sess_timeout_time; + u32 oldest_index; + snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; + oldest_index = clib_dlist_remove_head (tsm->lru_pool, head_index); + if (~0 != oldest_index) + { + oldest_elt = pool_elt_at_index (tsm->lru_pool, oldest_index); + s = pool_elt_at_index (tsm->sessions, oldest_elt->value); + + sess_timeout_time = + s->last_heard + (f64) nat44_session_get_timeout (sm, s); + if (now >= sess_timeout_time + || (s->tcp_closed_timestamp && now >= s->tcp_closed_timestamp)) + { + nat_free_session_data (sm, s, thread_index, 0); + nat_ed_session_delete (sm, s, thread_index, 0); + return 1; + } + else + { + clib_dlist_addhead (tsm->lru_pool, head_index, oldest_index); + } + } + return 0; +} + +static_always_inline int +nat_lru_free_one (snat_main_t * sm, int thread_index, f64 now) +{ + snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; + int rc = 0; +#define _(p) \ + if ((rc = nat_lru_free_one_with_head (sm, thread_index, now, \ + tsm->p##_lru_head_index))) \ + { \ + return rc; \ + } + _(tcp_trans); + _(udp); + _(unk_proto); + _(icmp); + _(tcp_estab); +#undef _ + return 0; +} + +static_always_inline snat_session_t * +nat_ed_session_alloc (snat_main_t * sm, u32 thread_index, f64 now, u8 proto) +{ + snat_session_t *s; + snat_main_per_thread_data_t *tsm = &sm->per_thread_data[thread_index]; + + nat_lru_free_one (sm, thread_index, now); + + pool_get (tsm->sessions, s); + clib_memset (s, 0, sizeof (*s)); + + nat_ed_lru_insert (tsm, s, now, proto); + + s->ha_last_refreshed = now; + vlib_set_simple_counter (&sm->total_sessions, thread_index, 0, + pool_elts (tsm->sessions)); + return s; +} + +#endif -- cgit 1.2.3-korg