2 * Copyright (c) 2018 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
17 * @brief NAT plugin client-IP based session affinity for load-balancing
20 #include <nat/nat_affinity.h>
23 nat_affinity_main_t nat_affinity_main;
25 #define AFFINITY_HASH_BUCKETS 65536
26 #define AFFINITY_HASH_MEMORY (2 << 25)
29 format_affinity_kvp (u8 * s, va_list * args)
31 clib_bihash_kv_16_8_t *v = va_arg (*args, clib_bihash_kv_16_8_t *);
34 k.as_u64[0] = v->key[0];
35 k.as_u64[1] = v->key[1];
37 s = format (s, "client %U backend %U:%d proto %U index %llu",
38 format_ip4_address, &k.client_addr,
39 format_ip4_address, &k.service_addr,
40 clib_net_to_host_u16 (k.service_port),
41 format_nat_protocol, k.proto);
47 nat_affinity_enable ()
49 nat_affinity_main_t *nam = &nat_affinity_main;
50 vlib_thread_main_t *tm = vlib_get_thread_main ();
52 if (tm->n_vlib_mains > 1)
53 clib_spinlock_init (&nam->affinity_lock);
54 clib_bihash_init_16_8 (&nam->affinity_hash, "nat-affinity",
55 AFFINITY_HASH_BUCKETS, AFFINITY_HASH_MEMORY);
56 clib_bihash_set_kvp_format_fn_16_8 (&nam->affinity_hash,
61 nat_affinity_disable ()
63 nat_affinity_main_t *nam = &nat_affinity_main;
64 vlib_thread_main_t *tm = vlib_get_thread_main ();
66 if (tm->n_vlib_mains > 1)
67 clib_spinlock_free (&nam->affinity_lock);
68 clib_bihash_free_16_8 (&nam->affinity_hash);
72 nat_affinity_init (vlib_main_t * vm)
74 nat_affinity_main_t *nam = &nat_affinity_main;
79 static_always_inline void
80 make_affinity_kv (clib_bihash_kv_16_8_t * kv, ip4_address_t client_addr,
81 ip4_address_t service_addr, u8 proto, u16 service_port)
83 nat_affinity_key_t *key = (nat_affinity_key_t *) kv->key;
85 key->client_addr = client_addr;
86 key->service_addr = service_addr;
88 key->service_port = service_port;
94 nat_affinity_get_per_service_list_head_index (void)
96 nat_affinity_main_t *nam = &nat_affinity_main;
97 dlist_elt_t *head_elt;
99 clib_spinlock_lock_if_init (&nam->affinity_lock);
101 pool_get (nam->list_pool, head_elt);
102 clib_dlist_init (nam->list_pool, head_elt - nam->list_pool);
104 clib_spinlock_unlock_if_init (&nam->affinity_lock);
106 return head_elt - nam->list_pool;
110 nat_affinity_flush_service (u32 affinity_per_service_list_head_index)
112 nat_affinity_main_t *nam = &nat_affinity_main;
116 clib_bihash_kv_16_8_t kv;
118 clib_spinlock_lock_if_init (&nam->affinity_lock);
121 clib_dlist_remove_head (nam->list_pool,
122 affinity_per_service_list_head_index)) !=
125 elt = pool_elt_at_index (nam->list_pool, elt_index);
126 a = pool_elt_at_index (nam->affinity_pool, elt->value);
127 kv.key[0] = a->key.as_u64[0];
128 kv.key[1] = a->key.as_u64[1];
129 pool_put_index (nam->affinity_pool, elt->value);
130 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, &kv, 0))
131 nat_elog_warn ("affinity key del failed");
132 pool_put_index (nam->list_pool, elt_index);
134 pool_put_index (nam->list_pool, affinity_per_service_list_head_index);
136 clib_spinlock_unlock_if_init (&nam->affinity_lock);
140 nat_affinity_find_and_lock (ip4_address_t client_addr,
141 ip4_address_t service_addr, u8 proto,
142 u16 service_port, u8 * backend_index)
144 nat_affinity_main_t *nam = &nat_affinity_main;
145 clib_bihash_kv_16_8_t kv, value;
149 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
150 clib_spinlock_lock_if_init (&nam->affinity_lock);
151 if (clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
157 a = pool_elt_at_index (nam->affinity_pool, value.value);
158 /* if already expired delete */
161 if (a->expire < vlib_time_now (nam->vlib_main))
163 clib_dlist_remove (nam->list_pool, a->per_service_index);
164 pool_put_index (nam->list_pool, a->per_service_index);
165 pool_put_index (nam->affinity_pool, value.value);
166 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, &kv, 0))
167 nat_elog_warn ("affinity key del failed");
173 *backend_index = a->backend_index;
176 clib_spinlock_unlock_if_init (&nam->affinity_lock);
181 affinity_is_expired_cb (clib_bihash_kv_16_8_t * kv, void *arg)
183 nat_affinity_main_t *nam = &nat_affinity_main;
186 a = pool_elt_at_index (nam->affinity_pool, kv->value);
189 if (a->expire < vlib_time_now (nam->vlib_main))
191 clib_dlist_remove (nam->list_pool, a->per_service_index);
192 pool_put_index (nam->list_pool, a->per_service_index);
193 pool_put_index (nam->affinity_pool, kv->value);
194 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, kv, 0))
195 nat_elog_warn ("affinity key del failed");
204 nat_affinity_create_and_lock (ip4_address_t client_addr,
205 ip4_address_t service_addr, u8 proto,
206 u16 service_port, u8 backend_index,
208 u32 affinity_per_service_list_head_index)
210 nat_affinity_main_t *nam = &nat_affinity_main;
211 clib_bihash_kv_16_8_t kv, value;
213 dlist_elt_t *list_elt;
216 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
217 clib_spinlock_lock_if_init (&nam->affinity_lock);
218 if (!clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
221 nat_elog_notice ("affinity key already exist");
225 pool_get (nam->affinity_pool, a);
226 kv.value = a - nam->affinity_pool;
228 clib_bihash_add_or_overwrite_stale_16_8 (&nam->affinity_hash, &kv,
229 affinity_is_expired_cb, NULL);
232 nat_elog_notice ("affinity key add failed");
233 pool_put (nam->affinity_pool, a);
237 pool_get (nam->list_pool, list_elt);
238 clib_dlist_init (nam->list_pool, list_elt - nam->list_pool);
239 list_elt->value = a - nam->affinity_pool;
240 a->per_service_index = list_elt - nam->list_pool;
241 a->backend_index = backend_index;
243 a->sticky_time = sticky_time;
244 a->key.as_u64[0] = kv.key[0];
245 a->key.as_u64[1] = kv.key[1];
246 clib_dlist_addtail (nam->list_pool, affinity_per_service_list_head_index,
247 a->per_service_index);
250 clib_spinlock_unlock_if_init (&nam->affinity_lock);
255 nat_affinity_unlock (ip4_address_t client_addr, ip4_address_t service_addr,
256 u8 proto, u16 service_port)
258 nat_affinity_main_t *nam = &nat_affinity_main;
259 clib_bihash_kv_16_8_t kv, value;
262 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
263 clib_spinlock_lock_if_init (&nam->affinity_lock);
264 if (clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
267 a = pool_elt_at_index (nam->affinity_pool, value.value);
270 a->expire = (u64) a->sticky_time + vlib_time_now (nam->vlib_main);
273 clib_spinlock_unlock_if_init (&nam->affinity_lock);
277 * fd.io coding-style-patch-verification: ON
280 * eval: (c-set-style "gnu")