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_snat_protocol, k.proto);
47 nat_affinity_init (vlib_main_t * vm)
49 nat_affinity_main_t *nam = &nat_affinity_main;
50 vlib_thread_main_t *tm = vlib_get_thread_main ();
51 clib_error_t *error = 0;
53 if (tm->n_vlib_mains > 1)
54 clib_spinlock_init (&nam->affinity_lock);
56 clib_bihash_init_16_8 (&nam->affinity_hash, "nat-affinity",
57 AFFINITY_HASH_BUCKETS, AFFINITY_HASH_MEMORY);
58 clib_bihash_set_kvp_format_fn_16_8 (&nam->affinity_hash,
66 static_always_inline void
67 make_affinity_kv (clib_bihash_kv_16_8_t * kv, ip4_address_t client_addr,
68 ip4_address_t service_addr, u8 proto, u16 service_port)
70 nat_affinity_key_t *key = (nat_affinity_key_t *) kv->key;
72 key->client_addr = client_addr;
73 key->service_addr = service_addr;
75 key->service_port = service_port;
81 nat_affinity_get_per_service_list_head_index (void)
83 nat_affinity_main_t *nam = &nat_affinity_main;
84 dlist_elt_t *head_elt;
86 clib_spinlock_lock_if_init (&nam->affinity_lock);
88 pool_get (nam->list_pool, head_elt);
89 clib_dlist_init (nam->list_pool, head_elt - nam->list_pool);
91 clib_spinlock_unlock_if_init (&nam->affinity_lock);
93 return head_elt - nam->list_pool;
97 nat_affinity_flush_service (u32 affinity_per_service_list_head_index)
99 nat_affinity_main_t *nam = &nat_affinity_main;
103 clib_bihash_kv_16_8_t kv;
105 clib_spinlock_lock_if_init (&nam->affinity_lock);
108 clib_dlist_remove_head (nam->list_pool,
109 affinity_per_service_list_head_index)) !=
112 elt = pool_elt_at_index (nam->list_pool, elt_index);
113 a = pool_elt_at_index (nam->affinity_pool, elt->value);
114 kv.key[0] = a->key.as_u64[0];
115 kv.key[1] = a->key.as_u64[1];
116 pool_put_index (nam->affinity_pool, elt->value);
117 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, &kv, 0))
118 nat_elog_warn ("affinity key del failed");
119 pool_put_index (nam->list_pool, elt_index);
121 pool_put_index (nam->list_pool, affinity_per_service_list_head_index);
123 clib_spinlock_unlock_if_init (&nam->affinity_lock);
127 nat_affinity_find_and_lock (ip4_address_t client_addr,
128 ip4_address_t service_addr, u8 proto,
129 u16 service_port, u8 * backend_index)
131 nat_affinity_main_t *nam = &nat_affinity_main;
132 clib_bihash_kv_16_8_t kv, value;
136 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
137 clib_spinlock_lock_if_init (&nam->affinity_lock);
138 if (clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
144 a = pool_elt_at_index (nam->affinity_pool, value.value);
145 /* if already expired delete */
148 if (a->expire < vlib_time_now (nam->vlib_main))
150 clib_dlist_remove (nam->list_pool, a->per_service_index);
151 pool_put_index (nam->list_pool, a->per_service_index);
152 pool_put_index (nam->affinity_pool, value.value);
153 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, &kv, 0))
154 nat_elog_warn ("affinity key del failed");
160 *backend_index = a->backend_index;
163 clib_spinlock_unlock_if_init (&nam->affinity_lock);
168 affinity_is_expired_cb (clib_bihash_kv_16_8_t * kv, void *arg)
170 nat_affinity_main_t *nam = &nat_affinity_main;
173 a = pool_elt_at_index (nam->affinity_pool, kv->value);
176 if (a->expire < vlib_time_now (nam->vlib_main))
178 clib_dlist_remove (nam->list_pool, a->per_service_index);
179 pool_put_index (nam->list_pool, a->per_service_index);
180 pool_put_index (nam->affinity_pool, kv->value);
181 if (clib_bihash_add_del_16_8 (&nam->affinity_hash, kv, 0))
182 nat_elog_warn ("affinity key del failed");
191 nat_affinity_create_and_lock (ip4_address_t client_addr,
192 ip4_address_t service_addr, u8 proto,
193 u16 service_port, u8 backend_index,
195 u32 affinity_per_service_list_head_index)
197 nat_affinity_main_t *nam = &nat_affinity_main;
198 clib_bihash_kv_16_8_t kv, value;
200 dlist_elt_t *list_elt;
203 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
204 clib_spinlock_lock_if_init (&nam->affinity_lock);
205 if (!clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
208 nat_elog_notice ("affinity key already exist");
212 pool_get (nam->affinity_pool, a);
213 kv.value = a - nam->affinity_pool;
215 clib_bihash_add_or_overwrite_stale_16_8 (&nam->affinity_hash, &kv,
216 affinity_is_expired_cb, NULL);
219 nat_elog_notice ("affinity key add failed");
220 pool_put (nam->affinity_pool, a);
224 pool_get (nam->list_pool, list_elt);
225 clib_dlist_init (nam->list_pool, list_elt - nam->list_pool);
226 list_elt->value = a - nam->affinity_pool;
227 a->per_service_index = list_elt - nam->list_pool;
228 a->backend_index = backend_index;
230 a->sticky_time = sticky_time;
231 a->key.as_u64[0] = kv.key[0];
232 a->key.as_u64[1] = kv.key[1];
233 clib_dlist_addtail (nam->list_pool, affinity_per_service_list_head_index,
234 a->per_service_index);
237 clib_spinlock_unlock_if_init (&nam->affinity_lock);
242 nat_affinity_unlock (ip4_address_t client_addr, ip4_address_t service_addr,
243 u8 proto, u16 service_port)
245 nat_affinity_main_t *nam = &nat_affinity_main;
246 clib_bihash_kv_16_8_t kv, value;
249 make_affinity_kv (&kv, client_addr, service_addr, proto, service_port);
250 clib_spinlock_lock_if_init (&nam->affinity_lock);
251 if (clib_bihash_search_16_8 (&nam->affinity_hash, &kv, &value))
254 a = pool_elt_at_index (nam->affinity_pool, value.value);
257 a->expire = (u64) a->sticky_time + vlib_time_now (nam->vlib_main);
260 clib_spinlock_unlock_if_init (&nam->affinity_lock);
264 * fd.io coding-style-patch-verification: ON
267 * eval: (c-set-style "gnu")