lb: add source ip based sticky load balancing

This patch adds source ip based sticky session, which is already
implemented in many hardware LBs and software LBs. Note that sticky
sessions may be reset if the hash is recalculated as ASs are added
or deleted.

Since this feature is unrelated to the other existing options, the
lb_add_del_vip API version has been upgraded to v2 and a new option
"src_ip_sticky" has been added.

Type: feature
Signed-off-by: Nobuhiro MIKI <nmiki@yahoo-corp.jp>
Change-Id: I3eb3680a28defbc701f28c873933ec2fb54544ab

1 files changed, 128 insertions, 1 deletions

diff --git a/src/plugins/lb/lb.c b/src/plugins/lb/lb.c
index dfdc5066a3d..782833495c1 100644
--- a/src/plugins/lb/lb.c
+++ b/src/plugins/lb/lb.c
@@ -93,6 +93,78 @@ const static char* const * const lb_dpo_nat6_port_nodes[DPO_PROTO_NUM] =
         [DPO_PROTO_IP6]  = lb_dpo_nat6_ip6_port,
     };
 
+const static char *const lb_dpo_gre4_ip4_sticky[] = { "lb4-gre4-sticky",
+						      NULL };
+const static char *const lb_dpo_gre4_ip6_sticky[] = { "lb6-gre4-sticky",
+						      NULL };
+const static char *const *const lb_dpo_gre4_sticky_nodes[DPO_PROTO_NUM] = {
+  [DPO_PROTO_IP4] = lb_dpo_gre4_ip4_sticky,
+  [DPO_PROTO_IP6] = lb_dpo_gre4_ip6_sticky,
+};
+
+const static char *const lb_dpo_gre6_ip4_sticky[] = { "lb4-gre6-sticky",
+						      NULL };
+const static char *const lb_dpo_gre6_ip6_sticky[] = { "lb6-gre6-sticky",
+						      NULL };
+const static char *const *const lb_dpo_gre6_sticky_nodes[DPO_PROTO_NUM] = {
+  [DPO_PROTO_IP4] = lb_dpo_gre6_ip4_sticky,
+  [DPO_PROTO_IP6] = lb_dpo_gre6_ip6_sticky,
+};
+
+const static char *const lb_dpo_gre4_ip4_port_sticky[] = {
+  "lb4-gre4-port-sticky", NULL
+};
+const static char *const lb_dpo_gre4_ip6_port_sticky[] = {
+  "lb6-gre4-port-sticky", NULL
+};
+const static char *const
+  *const lb_dpo_gre4_port_sticky_nodes[DPO_PROTO_NUM] = {
+    [DPO_PROTO_IP4] = lb_dpo_gre4_ip4_port_sticky,
+    [DPO_PROTO_IP6] = lb_dpo_gre4_ip6_port_sticky,
+  };
+
+const static char *const lb_dpo_gre6_ip4_port_sticky[] = {
+  "lb4-gre6-port-sticky", NULL
+};
+const static char *const lb_dpo_gre6_ip6_port_sticky[] = {
+  "lb6-gre6-port-sticky", NULL
+};
+const static char *const
+  *const lb_dpo_gre6_port_sticky_nodes[DPO_PROTO_NUM] = {
+    [DPO_PROTO_IP4] = lb_dpo_gre6_ip4_port_sticky,
+    [DPO_PROTO_IP6] = lb_dpo_gre6_ip6_port_sticky,
+  };
+
+const static char *const lb_dpo_l3dsr_ip4_sticky[] = { "lb4-l3dsr-sticky",
+						       NULL };
+const static char *const *const lb_dpo_l3dsr_sticky_nodes[DPO_PROTO_NUM] = {
+  [DPO_PROTO_IP4] = lb_dpo_l3dsr_ip4_sticky,
+};
+
+const static char *const lb_dpo_l3dsr_ip4_port_sticky[] = {
+  "lb4-l3dsr-port-sticky", NULL
+};
+const static char *const
+  *const lb_dpo_l3dsr_port_sticky_nodes[DPO_PROTO_NUM] = {
+    [DPO_PROTO_IP4] = lb_dpo_l3dsr_ip4_port_sticky,
+  };
+
+const static char *const lb_dpo_nat4_ip4_port_sticky[] = {
+  "lb4-nat4-port-sticky", NULL
+};
+const static char *const
+  *const lb_dpo_nat4_port_sticky_nodes[DPO_PROTO_NUM] = {
+    [DPO_PROTO_IP4] = lb_dpo_nat4_ip4_port_sticky,
+  };
+
+const static char *const lb_dpo_nat6_ip6_port_sticky[] = {
+  "lb6-nat6-port-sticky", NULL
+};
+const static char *const
+  *const lb_dpo_nat6_port_sticky_nodes[DPO_PROTO_NUM] = {
+    [DPO_PROTO_IP6] = lb_dpo_nat6_ip6_port_sticky,
+  };
+
 u32 lb_hash_time_now(vlib_main_t * vm)
 {
   return (u32) (vlib_time_now(vm) + 10000);
@@ -198,15 +270,18 @@ u8 *format_lb_vip_detailed (u8 * s, va_list * args)
   lb_vip_t *vip = va_arg (*args, lb_vip_t *);
   u32 indent = format_get_indent (s);
 
-  s = format(s, "%U %U [%lu] %U%s\n"
+  /* clang-format off */
+  s = format(s, "%U %U [%lu] %U%s%s\n"
                    "%U  new_size:%u\n",
                   format_white_space, indent,
                   format_lb_vip_type, vip->type,
                   vip - lbm->vips,
                   format_ip46_prefix, &vip->prefix, (u32) vip->plen, IP46_TYPE_ANY,
+                  lb_vip_is_src_ip_sticky (vip) ? " src_ip_sticky" : "",
                   (vip->flags & LB_VIP_FLAGS_USED)?"":" removed",
                   format_white_space, indent,
                   vip->new_flow_table_mask + 1);
+  /* clang-format on */
 
   if (vip->port != 0)
     {
@@ -949,6 +1024,22 @@ static void lb_vip_add_adjacency(lb_main_t *lbm, lb_vip_t *vip,
     dpo_type = lbm->dpo_nat4_port_type;
   else if (lb_vip_is_nat6_port(vip))
     dpo_type = lbm->dpo_nat6_port_type;
+  else if (lb_vip_is_gre4_sticky (vip))
+    dpo_type = lbm->dpo_gre4_sticky_type;
+  else if (lb_vip_is_gre6_sticky (vip))
+    dpo_type = lbm->dpo_gre6_sticky_type;
+  else if (lb_vip_is_gre4_port_sticky (vip))
+    dpo_type = lbm->dpo_gre4_port_sticky_type;
+  else if (lb_vip_is_gre6_port_sticky (vip))
+    dpo_type = lbm->dpo_gre6_port_sticky_type;
+  else if (lb_vip_is_l3dsr_sticky (vip))
+    dpo_type = lbm->dpo_l3dsr_sticky_type;
+  else if (lb_vip_is_l3dsr_port_sticky (vip))
+    dpo_type = lbm->dpo_l3dsr_port_sticky_type;
+  else if (lb_vip_is_nat4_port_sticky (vip))
+    dpo_type = lbm->dpo_nat4_port_sticky_type;
+  else if (lb_vip_is_nat6_port_sticky (vip))
+    dpo_type = lbm->dpo_nat6_port_sticky_type;
 
   dpo_set(&dpo, dpo_type, proto, *vip_prefix_index);
   fib_table_entry_special_dpo_add(0,
@@ -1147,6 +1238,10 @@ int lb_vip_add(lb_vip_add_args_t args, u32 *vip_index)
     }
 
   vip->flags = LB_VIP_FLAGS_USED;
+  if (args.src_ip_sticky)
+    {
+      vip->flags |= LB_VIP_FLAGS_SRC_IP_STICKY;
+    }
   vip->as_indexes = 0;
 
   //Validate counters
@@ -1311,6 +1406,22 @@ lb_as_stack (lb_as_t *as)
     dpo_type = lbm->dpo_nat4_port_type;
   else if (lb_vip_is_nat6_port(vip))
     dpo_type = lbm->dpo_nat6_port_type;
+  else if (lb_vip_is_gre4_sticky (vip))
+    dpo_type = lbm->dpo_gre4_sticky_type;
+  else if (lb_vip_is_gre6_sticky (vip))
+    dpo_type = lbm->dpo_gre6_sticky_type;
+  else if (lb_vip_is_gre4_port_sticky (vip))
+    dpo_type = lbm->dpo_gre4_port_sticky_type;
+  else if (lb_vip_is_gre6_port_sticky (vip))
+    dpo_type = lbm->dpo_gre6_port_sticky_type;
+  else if (lb_vip_is_l3dsr_sticky (vip))
+    dpo_type = lbm->dpo_l3dsr_sticky_type;
+  else if (lb_vip_is_l3dsr_port_sticky (vip))
+    dpo_type = lbm->dpo_l3dsr_port_sticky_type;
+  else if (lb_vip_is_nat4_port_sticky (vip))
+    dpo_type = lbm->dpo_nat4_port_sticky_type;
+  else if (lb_vip_is_nat6_port_sticky (vip))
+    dpo_type = lbm->dpo_nat6_port_sticky_type;
 
   dpo_stack(dpo_type,
             lb_vip_is_ip4(vip->type)?DPO_PROTO_IP4:DPO_PROTO_IP6,
@@ -1412,6 +1523,22 @@ lb_init (vlib_main_t * vm)
                                                   lb_dpo_nat4_port_nodes);
   lbm->dpo_nat6_port_type = dpo_register_new_type(&lb_vft,
                                                   lb_dpo_nat6_port_nodes);
+  lbm->dpo_gre4_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_gre4_sticky_nodes);
+  lbm->dpo_gre6_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_gre6_sticky_nodes);
+  lbm->dpo_gre4_port_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_gre4_port_sticky_nodes);
+  lbm->dpo_gre6_port_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_gre6_port_sticky_nodes);
+  lbm->dpo_l3dsr_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_l3dsr_sticky_nodes);
+  lbm->dpo_l3dsr_port_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_l3dsr_port_sticky_nodes);
+  lbm->dpo_nat4_port_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_nat4_port_sticky_nodes);
+  lbm->dpo_nat6_port_sticky_type =
+    dpo_register_new_type (&lb_vft, lb_dpo_nat6_port_sticky_nodes);
   lbm->fib_node_type = fib_node_register_new_type ("lb", &lb_fib_node_vft);
 
   //Init AS reference counters