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, 257 insertions, 22 deletions

diff --git a/src/plugins/lb/node.c b/src/plugins/lb/node.c
index b5e9da71376..f823ea9ce3c 100644
--- a/src/plugins/lb/node.c
+++ b/src/plugins/lb/node.c
@@ -174,8 +174,8 @@ lb_node_get_other_ports6 (ip6_header_t *ip60)
 }
 
 static_always_inline void
-lb_node_get_hash (lb_main_t *lbm, vlib_buffer_t *p, u8 is_input_v4,
-                  u32 *hash, u32 *vip_idx, u8 per_port_vip)
+lb_node_get_hash (lb_main_t *lbm, vlib_buffer_t *p, u8 is_input_v4, u32 *hash,
+		  u32 *vip_idx, u8 per_port_vip, u8 src_ip_sticky)
 {
   vip_port_key_t key;
   clib_bihash_kv_8_8_t kv, value;
@@ -203,7 +203,15 @@ lb_node_get_hash (lb_main_t *lbm, vlib_buffer_t *p, u8 is_input_v4,
       else
         ports = lb_node_get_other_ports4 (ip40);
 
-      *hash = lb_hash_hash (*((u64 *) &ip40->address_pair), ports, 0, 0, 0);
+      if (src_ip_sticky)
+	{
+	  *hash = lb_hash_hash (*((u64 *) &ip40->address_pair), 0, 0, 0, 0);
+	}
+      else
+	{
+	  *hash =
+	    lb_hash_hash (*((u64 *) &ip40->address_pair), ports, 0, 0, 0);
+	}
 
       if (per_port_vip)
         {
@@ -225,10 +233,18 @@ lb_node_get_hash (lb_main_t *lbm, vlib_buffer_t *p, u8 is_input_v4,
       else
         ports = lb_node_get_other_ports6 (ip60);
 
-      *hash = lb_hash_hash (ip60->src_address.as_u64[0],
-                           ip60->src_address.as_u64[1],
-                           ip60->dst_address.as_u64[0],
-                           ip60->dst_address.as_u64[1], ports);
+      if (src_ip_sticky)
+	{
+	  *hash = lb_hash_hash (
+	    ip60->src_address.as_u64[0], ip60->src_address.as_u64[1],
+	    ip60->dst_address.as_u64[0], ip60->dst_address.as_u64[1], 0);
+	}
+      else
+	{
+	  *hash = lb_hash_hash (
+	    ip60->src_address.as_u64[0], ip60->src_address.as_u64[1],
+	    ip60->dst_address.as_u64[0], ip60->dst_address.as_u64[1], ports);
+	}
 
       if (per_port_vip)
         {
@@ -251,13 +267,15 @@ lb_node_get_hash (lb_main_t *lbm, vlib_buffer_t *p, u8 is_input_v4,
     }
 }
 
+/* clang-format off */
 static_always_inline uword
 lb_node_fn (vlib_main_t * vm,
             vlib_node_runtime_t * node,
             vlib_frame_t * frame,
             u8 is_input_v4, //Compile-time parameter stating that is input is v4 (or v6)
             lb_encap_type_t encap_type, //Compile-time parameter is GRE4/GRE6/L3DSR/NAT4/NAT6
-            u8 per_port_vip) //Compile-time parameter stating that is per_port_vip or not
+            u8 per_port_vip, //Compile-time parameter stating that is per_port_vip or not
+            u8 src_ip_sticky) //Compile-time parameter stating that is source ip based sticky or not
 {
   lb_main_t *lbm = &lb_main;
   u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
@@ -275,7 +293,7 @@ lb_node_fn (vlib_main_t * vm,
     {
       vlib_buffer_t *p0 = vlib_get_buffer (vm, from[0]);
       lb_node_get_hash (lbm, p0, is_input_v4, &nexthash0,
-                        &next_vip_idx0, per_port_vip);
+                        &next_vip_idx0, per_port_vip, src_ip_sticky);
     }
 
   while (n_left_from > 0)
@@ -300,7 +318,7 @@ lb_node_fn (vlib_main_t * vm,
               //Compute next hash and prefetch bucket
               lb_node_get_hash (lbm, p1, is_input_v4,
                                 &nexthash0, &next_vip_idx0,
-                                per_port_vip);
+                                per_port_vip, src_ip_sticky);
               lb_hash_prefetch_bucket (sticky_ht, nexthash0);
               //Prefetch for encap, next
               CLIB_PREFETCH(vlib_buffer_get_current (p1) - 64, 64, STORE);
@@ -565,6 +583,7 @@ lb_node_fn (vlib_main_t * vm,
 
   return frame->n_vectors;
 }
+/* clang-format on */
 
 u8 *
 format_nodeport_lb_trace (u8 * s, va_list * args)
@@ -947,84 +966,168 @@ static uword
 lb6_gre6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                   vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 0);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 0, 0);
 }
 
 static uword
 lb6_gre4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                   vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 0);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 0, 0);
 }
 
 static uword
 lb4_gre6_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                   vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 0);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 0, 0);
 }
 
 static uword
 lb4_gre4_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                   vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 0);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 0, 0);
 }
 
 static uword
 lb6_gre6_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 1);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 1, 0);
 }
 
 static uword
 lb6_gre4_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 1);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 1, 0);
 }
 
 static uword
 lb4_gre6_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 1);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 1, 0);
 }
 
 static uword
 lb4_gre4_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 1);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 1, 0);
 }
 
 static uword
 lb4_l3dsr_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                         vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 0);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 0, 0);
 }
 
 static uword
 lb4_l3dsr_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                         vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 1);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 1, 0);
 }
 
 static uword
 lb6_nat6_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_NAT6, 1);
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_NAT6, 1, 0);
 }
 
 static uword
 lb4_nat4_port_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                        vlib_frame_t * frame)
 {
-  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_NAT4, 1);
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_NAT4, 1, 0);
+}
+
+static uword
+lb6_gre6_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			 vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 0, 1);
+}
+
+static uword
+lb6_gre4_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			 vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 0, 1);
+}
+
+static uword
+lb4_gre6_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			 vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 0, 1);
+}
+
+static uword
+lb4_gre4_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			 vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 0, 1);
+}
+
+static uword
+lb6_gre6_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE6, 1, 1);
+}
+
+static uword
+lb6_gre4_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_GRE4, 1, 1);
+}
+
+static uword
+lb4_gre6_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE6, 1, 1);
+}
+
+static uword
+lb4_gre4_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_GRE4, 1, 1);
+}
+
+static uword
+lb4_l3dsr_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			  vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 0, 1);
+}
+
+static uword
+lb4_l3dsr_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			       vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_L3DSR, 1, 1);
+}
+
+static uword
+lb6_nat6_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 0, LB_ENCAP_TYPE_NAT6, 1, 1);
+}
+
+static uword
+lb4_nat4_port_sticky_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			      vlib_frame_t *frame)
+{
+  return lb_node_fn (vm, node, frame, 1, LB_ENCAP_TYPE_NAT4, 1, 1);
 }
 
 static uword
@@ -1197,6 +1300,138 @@ VLIB_REGISTER_NODE (lb4_nat4_port_node) =
         { [LB_NEXT_DROP] = "error-drop" },
   };
 
+VLIB_REGISTER_NODE (lb6_gre6_sticky_node) = {
+  .function = lb6_gre6_sticky_node_fn,
+  .name = "lb6-gre6-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb6_gre4_sticky_node) = {
+  .function = lb6_gre4_sticky_node_fn,
+  .name = "lb6-gre4-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_gre6_sticky_node) = {
+  .function = lb4_gre6_sticky_node_fn,
+  .name = "lb4-gre6-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_gre4_sticky_node) = {
+  .function = lb4_gre4_sticky_node_fn,
+  .name = "lb4-gre4-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb6_gre6_port_sticky_node) = {
+  .function = lb6_gre6_port_sticky_node_fn,
+  .name = "lb6-gre6-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb6_gre4_port_sticky_node) = {
+  .function = lb6_gre4_port_sticky_node_fn,
+  .name = "lb6-gre4-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_gre6_port_sticky_node) = {
+  .function = lb4_gre6_port_sticky_node_fn,
+  .name = "lb4-gre6-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_gre4_port_sticky_node) = {
+  .function = lb4_gre4_port_sticky_node_fn,
+  .name = "lb4-gre4-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_l3dsr_port_sticky_node) = {
+  .function = lb4_l3dsr_port_sticky_node_fn,
+  .name = "lb4-l3dsr-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_l3dsr_sticky_node) = {
+  .function = lb4_l3dsr_sticky_node_fn,
+  .name = "lb4-l3dsr-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb6_nat6_port_sticky_node) = {
+  .function = lb6_nat6_port_sticky_node_fn,
+  .name = "lb6-nat6-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
+VLIB_REGISTER_NODE (lb4_nat4_port_sticky_node) = {
+  .function = lb4_nat4_port_sticky_node_fn,
+  .name = "lb4-nat4-port-sticky",
+  .vector_size = sizeof (u32),
+  .format_trace = format_lb_trace,
+  .n_errors = LB_N_ERROR,
+  .error_strings = lb_error_strings,
+  .n_next_nodes = LB_N_NEXT,
+  .next_nodes = { [LB_NEXT_DROP] = "error-drop" },
+};
+
 static uword
 lb4_nodeport_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
                       vlib_frame_t * frame)