acl-plugin: implement ACL lookup contexts for "ACL as a service" use by other plugins
[vpp.git] / src / plugins / acl / fa_node.c
index c0ff1a5..d29576a 100644 (file)
 #include <vnet/vnet.h>
 #include <vnet/pg/pg.h>
 #include <vppinfra/error.h>
+
+
 #include <acl/acl.h>
-#include "bihash_40_8.h"
+#include <vnet/ip/icmp46_packet.h>
 
+#include <plugins/acl/fa_node.h>
+#include <plugins/acl/acl.h>
+#include <plugins/acl/lookup_context.h>
+#include <plugins/acl/public_inlines.h>
+
+#include <vppinfra/bihash_40_8.h>
 #include <vppinfra/bihash_template.h>
 #include <vppinfra/bihash_template.c>
 
-#include "fa_node.h"
-#include "hash_lookup.h"
-
 typedef struct
 {
   u32 next_index;
   u32 sw_if_index;
+  u32 lc_index;
   u32 match_acl_in_index;
   u32 match_rule_index;
   u64 packet_info[6];
@@ -39,6 +45,61 @@ typedef struct
   u8 action;
 } acl_fa_trace_t;
 
+/* ICMPv4 invert type for stateful ACL */
+static const u8 icmp4_invmap[] = {
+  [ICMP4_echo_reply] = ICMP4_echo_request + 1,
+  [ICMP4_timestamp_reply] = ICMP4_timestamp_request + 1,
+  [ICMP4_information_reply] = ICMP4_information_request + 1,
+  [ICMP4_address_mask_reply] = ICMP4_address_mask_request + 1
+};
+
+/* Supported ICMPv4 messages for session creation */
+static const u8 icmp4_valid_new[] = {
+  [ICMP4_echo_request] = 1,
+  [ICMP4_timestamp_request] = 1,
+  [ICMP4_information_request] = 1,
+  [ICMP4_address_mask_request] = 1
+};
+
+/* ICMPv6 invert type for stateful ACL */
+static const u8 icmp6_invmap[] = {
+  [ICMP6_echo_reply - 128]   = ICMP6_echo_request + 1,
+  [ICMP6_node_information_response - 128] = ICMP6_node_information_request + 1
+};
+
+/* Supported ICMPv6 messages for session creation */
+static const u8 icmp6_valid_new[] = {
+  [ICMP6_echo_request - 128] = 1,
+  [ICMP6_node_information_request - 128] = 1
+};
+
+/* IP4 and IP6 protocol numbers of ICMP */
+static u8 icmp_protos[] = { IP_PROTOCOL_ICMP, IP_PROTOCOL_ICMP6 };
+
+static u8 *
+format_fa_5tuple (u8 * s, va_list * args)
+{
+  fa_5tuple_t *p5t = va_arg (*args, fa_5tuple_t *);
+
+  return format(s, "lc_index %d (lsb16 of sw_if_index %d) l3 %s%s %U -> %U"
+                   " l4 proto %d l4_valid %d port %d -> %d tcp flags (%s) %02x rsvd %x",
+                p5t->pkt.lc_index, p5t->l4.lsb_of_sw_if_index, p5t->pkt.is_ip6 ? "ip6" : "ip4",
+                p5t->pkt.is_nonfirst_fragment ? " non-initial fragment" : "",
+                format_ip46_address, &p5t->addr[0], p5t->pkt.is_ip6 ? IP46_TYPE_IP6 : IP46_TYPE_IP4,
+                format_ip46_address, &p5t->addr[1], p5t->pkt.is_ip6 ? IP46_TYPE_IP6 : IP46_TYPE_IP4,
+                p5t->l4.proto, p5t->pkt.l4_valid,
+                p5t->l4.port[0], p5t->l4.port[1],
+                p5t->pkt.tcp_flags_valid ? "valid": "invalid",
+                p5t->pkt.tcp_flags,
+                p5t->pkt.flags_reserved);
+}
+
+u8 *
+format_acl_plugin_5tuple (u8 * s, va_list * args)
+{
+  return format_fa_5tuple(s, args);
+}
+
 /* packet trace format function */
 static u8 *
 format_acl_fa_trace (u8 * s, va_list * args)
@@ -49,12 +110,15 @@ format_acl_fa_trace (u8 * s, va_list * args)
 
   s =
     format (s,
-           "acl-plugin: sw_if_index %d, next index %d, action: %d, match: acl %d rule %d trace_bits %08x\n"
+           "acl-plugin: lc_index: %d, sw_if_index %d, next index %d, action: %d, match: acl %d rule %d trace_bits %08x\n"
            "  pkt info %016llx %016llx %016llx %016llx %016llx %016llx",
-           t->sw_if_index, t->next_index, t->action, t->match_acl_in_index,
+           t->lc_index, t->sw_if_index, t->next_index, t->action, t->match_acl_in_index,
            t->match_rule_index, t->trace_bitmap,
            t->packet_info[0], t->packet_info[1], t->packet_info[2],
            t->packet_info[3], t->packet_info[4], t->packet_info[5]);
+
+  /* Now also print out the packet_info in a form usable by humans */
+  s = format (s, "\n   %U", format_fa_5tuple, t->packet_info);
   return s;
 }
 
@@ -84,447 +148,88 @@ static char *acl_fa_error_strings[] = {
 };
 /* *INDENT-ON* */
 
-static void *
-get_ptr_to_offset (vlib_buffer_t * b0, int offset)
-{
-  u8 *p = vlib_buffer_get_current (b0) + offset;
-  return p;
-}
-
-
 static int
-fa_acl_match_addr (ip46_address_t * addr1, ip46_address_t * addr2,
-                  int prefixlen, int is_ip6)
+acl_fa_ifc_has_sessions (acl_main_t * am, int sw_if_index0)
 {
-  if (prefixlen == 0)
-    {
-      /* match any always succeeds */
-      return 1;
-    }
-  if (is_ip6)
-    {
-      if (memcmp (addr1, addr2, prefixlen / 8))
-       {
-         /* If the starting full bytes do not match, no point in bittwidling the thumbs further */
-         return 0;
-       }
-      if (prefixlen % 8)
-       {
-         u8 b1 = *((u8 *) addr1 + 1 + prefixlen / 8);
-         u8 b2 = *((u8 *) addr2 + 1 + prefixlen / 8);
-         u8 mask0 = (0xff - ((1 << (8 - (prefixlen % 8))) - 1));
-         return (b1 & mask0) == b2;
-       }
-      else
-       {
-         /* The prefix fits into integer number of bytes, so nothing left to do */
-         return 1;
-       }
-    }
-  else
-    {
-      uint32_t a1 = ntohl (addr1->ip4.as_u32);
-      uint32_t a2 = ntohl (addr2->ip4.as_u32);
-      uint32_t mask0 = 0xffffffff - ((1 << (32 - prefixlen)) - 1);
-      return (a1 & mask0) == a2;
-    }
+  return am->fa_sessions_hash_is_initialized;
 }
 
 static int
-fa_acl_match_port (u16 port, u16 port_first, u16 port_last, int is_ip6)
+acl_fa_ifc_has_in_acl (acl_main_t * am, int sw_if_index0)
 {
-  return ((port >= port_first) && (port <= port_last));
+  int it_has = clib_bitmap_get (am->fa_in_acl_on_sw_if_index, sw_if_index0);
+  return it_has;
 }
 
-int
-single_acl_match_5tuple (acl_main_t * am, u32 acl_index, fa_5tuple_t * pkt_5tuple,
-                 int is_ip6, u8 * r_action, u32 * r_acl_match_p,
-                 u32 * r_rule_match_p, u32 * trace_bitmap)
+static int
+acl_fa_ifc_has_out_acl (acl_main_t * am, int sw_if_index0)
 {
-  int i;
-  acl_list_t *a;
-  acl_rule_t *r;
-
-  if (pool_is_free_index (am->acls, acl_index))
-    {
-      if (r_acl_match_p)
-       *r_acl_match_p = acl_index;
-      if (r_rule_match_p)
-       *r_rule_match_p = -1;
-      /* the ACL does not exist but is used for policy. Block traffic. */
-      return 0;
-    }
-  a = am->acls + acl_index;
-  for (i = 0; i < a->count; i++)
-    {
-      r = a->rules + i;
-      if (is_ip6 != r->is_ipv6)
-       {
-         continue;
-       }
-      if (!fa_acl_match_addr
-         (&pkt_5tuple->addr[1], &r->dst, r->dst_prefixlen, is_ip6))
-       continue;
-
-#ifdef FA_NODE_VERBOSE_DEBUG
-      clib_warning
-       ("ACL_FA_NODE_DBG acl %d rule %d pkt dst addr %U match rule addr %U/%d",
-        acl_index, i, format_ip46_address, &pkt_5tuple->addr[1],
-        IP46_TYPE_ANY, format_ip46_address, &r->dst, IP46_TYPE_ANY,
-        r->dst_prefixlen);
-#endif
-
-      if (!fa_acl_match_addr
-         (&pkt_5tuple->addr[0], &r->src, r->src_prefixlen, is_ip6))
-       continue;
-
-#ifdef FA_NODE_VERBOSE_DEBUG
-      clib_warning
-       ("ACL_FA_NODE_DBG acl %d rule %d pkt src addr %U match rule addr %U/%d",
-        acl_index, i, format_ip46_address, &pkt_5tuple->addr[0],
-        IP46_TYPE_ANY, format_ip46_address, &r->src, IP46_TYPE_ANY,
-        r->src_prefixlen);
-      clib_warning
-       ("ACL_FA_NODE_DBG acl %d rule %d trying to match pkt proto %d with rule %d",
-        acl_index, i, pkt_5tuple->l4.proto, r->proto);
-#endif
-      if (r->proto)
-       {
-         if (pkt_5tuple->l4.proto != r->proto)
-           continue;
-
-          if (PREDICT_FALSE (pkt_5tuple->pkt.is_nonfirst_fragment &&
-                     am->l4_match_nonfirst_fragment))
-          {
-            /* non-initial fragment with frag match configured - match this rule */
-            *trace_bitmap |= 0x80000000;
-            *r_action = r->is_permit;
-            if (r_acl_match_p)
-             *r_acl_match_p = acl_index;
-            if (r_rule_match_p)
-             *r_rule_match_p = i;
-            return 1;
-          }
-
-         /* A sanity check just to ensure we are about to match the ports extracted from the packet */
-         if (PREDICT_FALSE (!pkt_5tuple->pkt.l4_valid))
-           continue;
-
-#ifdef FA_NODE_VERBOSE_DEBUG
-         clib_warning
-           ("ACL_FA_NODE_DBG acl %d rule %d pkt proto %d match rule %d",
-            acl_index, i, pkt_5tuple->l4.proto, r->proto);
-#endif
-
-         if (!fa_acl_match_port
-             (pkt_5tuple->l4.port[0], r->src_port_or_type_first,
-              r->src_port_or_type_last, is_ip6))
-           continue;
-
-#ifdef FA_NODE_VERBOSE_DEBUG
-         clib_warning
-           ("ACL_FA_NODE_DBG acl %d rule %d pkt sport %d match rule [%d..%d]",
-            acl_index, i, pkt_5tuple->l4.port[0], r->src_port_or_type_first,
-            r->src_port_or_type_last);
-#endif
-
-         if (!fa_acl_match_port
-             (pkt_5tuple->l4.port[1], r->dst_port_or_code_first,
-              r->dst_port_or_code_last, is_ip6))
-           continue;
-
-#ifdef FA_NODE_VERBOSE_DEBUG
-         clib_warning
-           ("ACL_FA_NODE_DBG acl %d rule %d pkt dport %d match rule [%d..%d]",
-            acl_index, i, pkt_5tuple->l4.port[1], r->dst_port_or_code_first,
-            r->dst_port_or_code_last);
-#endif
-         if (pkt_5tuple->pkt.tcp_flags_valid
-             && ((pkt_5tuple->pkt.tcp_flags & r->tcp_flags_mask) !=
-                 r->tcp_flags_value))
-           continue;
-       }
-      /* everything matches! */
-#ifdef FA_NODE_VERBOSE_DEBUG
-      clib_warning ("ACL_FA_NODE_DBG acl %d rule %d FULL-MATCH, action %d",
-                   acl_index, i, r->is_permit);
-#endif
-      *r_action = r->is_permit;
-      if (r_acl_match_p)
-       *r_acl_match_p = acl_index;
-      if (r_rule_match_p)
-       *r_rule_match_p = i;
-      return 1;
-    }
-  return 0;
+  int it_has = clib_bitmap_get (am->fa_out_acl_on_sw_if_index, sw_if_index0);
+  return it_has;
 }
 
-static u8
-linear_multi_acl_match_5tuple (u32 sw_if_index, fa_5tuple_t * pkt_5tuple, int is_l2,
-                      int is_ip6, int is_input, u32 * acl_match_p,
-                      u32 * rule_match_p, u32 * trace_bitmap)
+/* Session keys match the packets received, and mirror the packets sent */
+static u32
+acl_make_5tuple_session_key (acl_main_t * am, int is_input, int is_ip6,
+                             u32 sw_if_index, fa_5tuple_t * p5tuple_pkt,
+                             fa_5tuple_t * p5tuple_sess)
 {
-  acl_main_t *am = &acl_main;
-  int i;
-  u32 *acl_vector;
-  u8 action = 0;
+  int src_index = is_input ? 0 : 1;
+  int dst_index = is_input ? 1 : 0;
+  u32 valid_new_sess = 1;
+  p5tuple_sess->addr[src_index] = p5tuple_pkt->addr[0];
+  p5tuple_sess->addr[dst_index] = p5tuple_pkt->addr[1];
+  p5tuple_sess->l4.as_u64 = p5tuple_pkt->l4.as_u64;
 
-  if (is_input)
+  if (PREDICT_TRUE(p5tuple_pkt->l4.proto != icmp_protos[is_ip6]))
     {
-      vec_validate (am->input_acl_vec_by_sw_if_index, sw_if_index);
-      acl_vector = am->input_acl_vec_by_sw_if_index[sw_if_index];
+      p5tuple_sess->l4.port[src_index] = p5tuple_pkt->l4.port[0];
+      p5tuple_sess->l4.port[dst_index] = p5tuple_pkt->l4.port[1];
     }
   else
     {
-      vec_validate (am->output_acl_vec_by_sw_if_index, sw_if_index);
-      acl_vector = am->output_acl_vec_by_sw_if_index[sw_if_index];
-    }
-  for (i = 0; i < vec_len (acl_vector); i++)
-    {
-#ifdef FA_NODE_VERBOSE_DEBUG
-      clib_warning ("ACL_FA_NODE_DBG: Trying to match ACL: %d",
-                   acl_vector[i]);
-#endif
-      if (single_acl_match_5tuple
-         (am, acl_vector[i], pkt_5tuple, is_ip6, &action,
-          acl_match_p, rule_match_p, trace_bitmap))
-       {
-         return action;
-       }
-    }
-  if (vec_len (acl_vector) > 0)
-    {
-      /* If there are ACLs and none matched, deny by default */
-      return 0;
-    }
-#ifdef FA_NODE_VERBOSE_DEBUG
-  clib_warning ("ACL_FA_NODE_DBG: No ACL on sw_if_index %d", sw_if_index);
-#endif
-  /* Deny by default. If there are no ACLs defined we should not be here. */
-  return 0;
-}
+      static const u8 * icmp_invmap[] = { icmp4_invmap, icmp6_invmap };
+      static const u8 * icmp_valid_new[] = { icmp4_valid_new, icmp6_valid_new };
+      static const u8 icmp_invmap_size[] = { sizeof(icmp4_invmap),
+                                             sizeof(icmp6_invmap) };
+      static const u8 icmp_valid_new_size[] = { sizeof(icmp4_valid_new),
+                                                sizeof(icmp6_valid_new) };
+      int type = is_ip6 ? p5tuple_pkt->l4.port[0]-128: p5tuple_pkt->l4.port[0];
 
-static u8
-multi_acl_match_5tuple (u32 sw_if_index, fa_5tuple_t * pkt_5tuple, int is_l2,
-                       int is_ip6, int is_input, u32 * acl_match_p,
-                       u32 * rule_match_p, u32 * trace_bitmap)
-{
-  acl_main_t *am = &acl_main;
-  if (am->use_hash_acl_matching) {
-    return hash_multi_acl_match_5tuple(sw_if_index, pkt_5tuple, is_l2, is_ip6,
-                                 is_input, acl_match_p, rule_match_p, trace_bitmap);
-  } else {
-    return linear_multi_acl_match_5tuple(sw_if_index, pkt_5tuple, is_l2, is_ip6,
-                                 is_input, acl_match_p, rule_match_p, trace_bitmap);
-  }
-}
-
-static int
-offset_within_packet (vlib_buffer_t * b0, int offset)
-{
-  /* For the purposes of this code, "within" means we have at least 8 bytes after it */
-  return (offset <= (b0->current_length - 8));
-}
+      p5tuple_sess->l4.port[0] = p5tuple_pkt->l4.port[0];
+      p5tuple_sess->l4.port[1] = p5tuple_pkt->l4.port[1];
 
-static void
-acl_fill_5tuple (acl_main_t * am, vlib_buffer_t * b0, int is_ip6,
-                int is_input, int is_l2_path, fa_5tuple_t * p5tuple_pkt)
-{
-  int l3_offset = ethernet_buffer_header_size(b0);
-  int l4_offset;
-  u16 ports[2];
-  u16 proto;
-  /* IP4 and IP6 protocol numbers of ICMP */
-  static u8 icmp_protos[] = { IP_PROTOCOL_ICMP, IP_PROTOCOL_ICMP6 };
-
-  if (is_input && !(is_l2_path))
-    {
-      l3_offset = 0;
-    }
-
-  /* key[0..3] contains src/dst address and is cleared/set below */
-  /* Remainder of the key and per-packet non-key data */
-  p5tuple_pkt->kv.key[4] = 0;
-  p5tuple_pkt->kv.value = 0;
-
-  if (is_ip6)
-    {
-      clib_memcpy (&p5tuple_pkt->addr,
-                  get_ptr_to_offset (b0,
-                                     offsetof (ip6_header_t,
-                                               src_address) + l3_offset),
-                  sizeof (p5tuple_pkt->addr));
-      proto =
-       *(u8 *) get_ptr_to_offset (b0,
-                                  offsetof (ip6_header_t,
-                                            protocol) + l3_offset);
-      l4_offset = l3_offset + sizeof (ip6_header_t);
-#ifdef FA_NODE_VERBOSE_DEBUG
-      clib_warning ("ACL_FA_NODE_DBG: proto: %d, l4_offset: %d", proto,
-                   l4_offset);
-#endif
-      /* IP6 EH handling is here, increment l4_offset if needs to, update the proto */
-      int need_skip_eh = clib_bitmap_get (am->fa_ipv6_known_eh_bitmap, proto);
-      if (PREDICT_FALSE (need_skip_eh))
-       {
-         while (need_skip_eh && offset_within_packet (b0, l4_offset))
-           {
-             /* Fragment header needs special handling */
-             if (PREDICT_FALSE(ACL_EH_FRAGMENT == proto))
-               {
-                 proto = *(u8 *) get_ptr_to_offset (b0, l4_offset);
-                 u16 frag_offset;
-                 clib_memcpy (&frag_offset, get_ptr_to_offset (b0, 2 + l4_offset), sizeof(frag_offset));
-                 frag_offset = ntohs(frag_offset) >> 3;
-                 if (frag_offset)
-                   {
-                      p5tuple_pkt->pkt.is_nonfirst_fragment = 1;
-                      /* invalidate L4 offset so we don't try to find L4 info */
-                      l4_offset += b0->current_length;
-                   }
-                 else
-                   {
-                     /* First fragment: skip the frag header and move on. */
-                     l4_offset += 8;
-                   }
-               }
-              else
-                {
-                 u8 nwords = *(u8 *) get_ptr_to_offset (b0, 1 + l4_offset);
-                 proto = *(u8 *) get_ptr_to_offset (b0, l4_offset);
-                 l4_offset += 8 * (1 + (u16) nwords);
-                }
-#ifdef FA_NODE_VERBOSE_DEBUG
-             clib_warning ("ACL_FA_NODE_DBG: new proto: %d, new offset: %d",
-                           proto, l4_offset);
-#endif
-             need_skip_eh =
-               clib_bitmap_get (am->fa_ipv6_known_eh_bitmap, proto);
-           }
-       }
-    }
-  else
-    {
-      p5tuple_pkt->kv.key[0] = 0;
-      p5tuple_pkt->kv.key[1] = 0;
-      p5tuple_pkt->kv.key[2] = 0;
-      p5tuple_pkt->kv.key[3] = 0;
-      clib_memcpy (&p5tuple_pkt->addr[0].ip4,
-                  get_ptr_to_offset (b0,
-                                     offsetof (ip4_header_t,
-                                               src_address) + l3_offset),
-                  sizeof (p5tuple_pkt->addr[0].ip4));
-      clib_memcpy (&p5tuple_pkt->addr[1].ip4,
-                  get_ptr_to_offset (b0,
-                                     offsetof (ip4_header_t,
-                                               dst_address) + l3_offset),
-                  sizeof (p5tuple_pkt->addr[1].ip4));
-      proto =
-       *(u8 *) get_ptr_to_offset (b0,
-                                  offsetof (ip4_header_t,
-                                            protocol) + l3_offset);
-      l4_offset = l3_offset + sizeof (ip4_header_t);
-      u16 flags_and_fragment_offset;
-      clib_memcpy (&flags_and_fragment_offset,
-                   get_ptr_to_offset (b0,
-                                      offsetof (ip4_header_t,
-                                                flags_and_fragment_offset)) + l3_offset,
-                                                sizeof(flags_and_fragment_offset));
-      flags_and_fragment_offset = ntohs (flags_and_fragment_offset);
-
-      /* non-initial fragments have non-zero offset */
-      if ((PREDICT_FALSE(0xfff & flags_and_fragment_offset)))
+      /*
+       * Invert ICMP type for valid icmp_invmap messages:
+       *  1) input node with outbound ACL interface
+       *  2) output node with inbound ACL interface
+       *
+       */
+      if ((is_input && acl_fa_ifc_has_out_acl(am, sw_if_index)) ||
+          (!is_input && acl_fa_ifc_has_in_acl(am, sw_if_index)))
         {
-          p5tuple_pkt->pkt.is_nonfirst_fragment = 1;
-          /* invalidate L4 offset so we don't try to find L4 info */
-          l4_offset += b0->current_length;
+          if (type >= 0 &&
+              type <= icmp_invmap_size[is_ip6] &&
+              icmp_invmap[is_ip6][type])
+            {
+              p5tuple_sess->l4.port[0] = icmp_invmap[is_ip6][type] - 1;
+            }
         }
 
-    }
-  p5tuple_pkt->l4.proto = proto;
-  if (PREDICT_TRUE (offset_within_packet (b0, l4_offset)))
-    {
-      p5tuple_pkt->pkt.l4_valid = 1;
-      if (icmp_protos[is_ip6] == proto)
-       {
-         /* type */
-         p5tuple_pkt->l4.port[0] =
-           *(u8 *) get_ptr_to_offset (b0,
-                                      l4_offset + offsetof (icmp46_header_t,
-                                                            type));
-         /* code */
-         p5tuple_pkt->l4.port[1] =
-           *(u8 *) get_ptr_to_offset (b0,
-                                      l4_offset + offsetof (icmp46_header_t,
-                                                            code));
-       }
-      else if ((IPPROTO_TCP == proto) || (IPPROTO_UDP == proto))
-       {
-         clib_memcpy (&ports,
-                      get_ptr_to_offset (b0,
-                                         l4_offset + offsetof (tcp_header_t,
-                                                               src_port)),
-                      sizeof (ports));
-         p5tuple_pkt->l4.port[0] = ntohs (ports[0]);
-         p5tuple_pkt->l4.port[1] = ntohs (ports[1]);
-
-         p5tuple_pkt->pkt.tcp_flags =
-           *(u8 *) get_ptr_to_offset (b0,
-                                      l4_offset + offsetof (tcp_header_t,
-                                                            flags));
-         p5tuple_pkt->pkt.tcp_flags_valid = (proto == IPPROTO_TCP);
-       }
       /*
-       * FIXME: rather than the above conditional, here could
-       * be a nice generic mechanism to extract two L4 values:
-       *
-       * have a per-protocol array of 4 elements like this:
-       *   u8 offset; to take the byte from, off L4 header
-       *   u8 mask; to mask it with, before storing
-       *
-       * this way we can describe UDP, TCP and ICMP[46] semantics,
-       * and add a sort of FPM-type behavior for other protocols.
-       *
-       * Of course, is it faster ? and is it needed ?
-       *
+       * ONLY ICMP messages defined in icmp4_valid_new/icmp6_valid_new table
+       * are allowed to create stateful ACL.
+       * The other messages will be forwarded without creating a reflexive ACL.
        */
+      if (type < 0 ||
+          type > icmp_valid_new_size[is_ip6] ||
+          !icmp_valid_new[is_ip6][type])
+        {
+          valid_new_sess = 0;
+        }
     }
-}
-
-
-/* Session keys match the packets received, and mirror the packets sent */
-static void
-acl_make_5tuple_session_key (int is_input, fa_5tuple_t * p5tuple_pkt,
-                            fa_5tuple_t * p5tuple_sess)
-{
-  int src_index = is_input ? 0 : 1;
-  int dst_index = is_input ? 1 : 0;
-  p5tuple_sess->addr[src_index] = p5tuple_pkt->addr[0];
-  p5tuple_sess->addr[dst_index] = p5tuple_pkt->addr[1];
-  p5tuple_sess->l4.as_u64 = p5tuple_pkt->l4.as_u64;
-  p5tuple_sess->l4.port[src_index] = p5tuple_pkt->l4.port[0];
-  p5tuple_sess->l4.port[dst_index] = p5tuple_pkt->l4.port[1];
-}
 
-
-static int
-acl_fa_ifc_has_sessions (acl_main_t * am, int sw_if_index0)
-{
-  return am->fa_sessions_hash_is_initialized;
-}
-
-static int
-acl_fa_ifc_has_in_acl (acl_main_t * am, int sw_if_index0)
-{
-  int it_has = clib_bitmap_get (am->fa_in_acl_on_sw_if_index, sw_if_index0);
-  return it_has;
-}
-
-static int
-acl_fa_ifc_has_out_acl (acl_main_t * am, int sw_if_index0)
-{
-  int it_has = clib_bitmap_get (am->fa_out_acl_on_sw_if_index, sw_if_index0);
-  return it_has;
+    return valid_new_sess;
 }
 
 
@@ -599,29 +304,44 @@ fa_session_get_timeout (acl_main_t * am, fa_session_t * sess)
 }
 
 static void
-acl_fa_ifc_init_sessions (acl_main_t * am, int sw_if_index0)
+acl_fa_verify_init_sessions (acl_main_t * am)
 {
-  /// FIXME-MULTICORE: lock around this function
-#ifdef FA_NODE_VERBOSE_DEBUG
-  clib_warning
-    ("Initializing bihash for sw_if_index %d num buckets %lu memory size %llu",
-     sw_if_index0, am->fa_conn_table_hash_num_buckets,
-     am->fa_conn_table_hash_memory_size);
-#endif
-  BV (clib_bihash_init) (&am->fa_sessions_hash,
+  if (!am->fa_sessions_hash_is_initialized) {
+    u16 wk;
+    /* Allocate the per-worker sessions pools */
+    for (wk = 0; wk < vec_len (am->per_worker_data); wk++) {
+      acl_fa_per_worker_data_t *pw = &am->per_worker_data[wk];
+
+      /*
+      * // In lieu of trying to preallocate the pool and its free bitmap, rather use pool_init_fixed
+      * pool_alloc_aligned(pw->fa_sessions_pool, am->fa_conn_table_max_entries, CLIB_CACHE_LINE_BYTES);
+      * clib_bitmap_validate(pool_header(pw->fa_sessions_pool)->free_bitmap, am->fa_conn_table_max_entries);
+      */
+      pool_init_fixed(pw->fa_sessions_pool, am->fa_conn_table_max_entries);
+    }
+
+    /* ... and the interface session hash table */
+    BV (clib_bihash_init) (&am->fa_sessions_hash,
                         "ACL plugin FA session bihash",
                         am->fa_conn_table_hash_num_buckets,
                         am->fa_conn_table_hash_memory_size);
-  am->fa_sessions_hash_is_initialized = 1;
+    am->fa_sessions_hash_is_initialized = 1;
+  }
 }
 
 static inline fa_session_t *get_session_ptr(acl_main_t *am, u16 thread_index, u32 session_index)
 {
   acl_fa_per_worker_data_t *pw = &am->per_worker_data[thread_index];
-  fa_session_t *sess = pw->fa_sessions_pool + session_index;
+  fa_session_t *sess = pool_is_free_index (pw->fa_sessions_pool, session_index) ? 0 : pool_elt_at_index(pw->fa_sessions_pool, session_index);
   return sess;
 }
 
+static inline int is_valid_session_ptr(acl_main_t *am, u16 thread_index, fa_session_t *sess)
+{
+  acl_fa_per_worker_data_t *pw = &am->per_worker_data[thread_index];
+  return ((sess != 0) && ((sess - pw->fa_sessions_pool) < pool_len(pw->fa_sessions_pool)));
+}
+
 static void
 acl_fa_conn_list_add_session (acl_main_t * am, fa_full_session_id_t sess_id, u64 now)
 {
@@ -644,13 +364,14 @@ acl_fa_conn_list_add_session (acl_main_t * am, fa_full_session_id_t sess_id, u64
     ASSERT(prev_sess->thread_index == sess->thread_index);
   }
   pw->fa_conn_list_tail[list_id] = sess_id.session_index;
+  
+#ifdef FA_NODE_VERBOSE_DEBUG
+    clib_warning("FA-SESSION-DEBUG: add session id %d on thread %d sw_if_index %d", sess_id.session_index, thread_index, sess->sw_if_index);
+#endif
   pw->serviced_sw_if_index_bitmap = clib_bitmap_set(pw->serviced_sw_if_index_bitmap, sess->sw_if_index, 1);
 
   if (~0 == pw->fa_conn_list_head[list_id]) {
     pw->fa_conn_list_head[list_id] = sess_id.session_index;
-    /* If it is a first conn in any list, kick the cleaner */
-    vlib_process_signal_event (am->vlib_main, am->fa_cleaner_node_index,
-                                 ACL_FA_CLEANER_RESCHEDULE, 0);
   }
 }
 
@@ -725,6 +446,7 @@ acl_fa_track_session (acl_main_t * am, int is_input, u32 sw_if_index, u64 now,
 static void
 acl_fa_delete_session (acl_main_t * am, u32 sw_if_index, fa_full_session_id_t sess_id)
 {
+  void *oldheap = clib_mem_set_heap(am->acl_mheap);
   fa_session_t *sess = get_session_ptr(am, sess_id.thread_index, sess_id.session_index);
   ASSERT(sess->thread_index == os_get_thread_index ());
   BV (clib_bihash_add_del) (&am->fa_sessions_hash,
@@ -733,8 +455,9 @@ acl_fa_delete_session (acl_main_t * am, u32 sw_if_index, fa_full_session_id_t se
   pool_put_index (pw->fa_sessions_pool, sess_id.session_index);
   /* Deleting from timer structures not needed,
      as the caller must have dealt with the timers. */
-  vec_validate (am->fa_session_dels_by_sw_if_index, sw_if_index);
-  am->fa_session_dels_by_sw_if_index[sw_if_index]++;
+  vec_validate (pw->fa_session_dels_by_sw_if_index, sw_if_index);
+  clib_mem_set_heap (oldheap);
+  pw->fa_session_dels_by_sw_if_index[sw_if_index]++;
   clib_smp_atomic_add(&am->fa_session_total_dels, 1);
 }
 
@@ -749,10 +472,14 @@ acl_fa_can_add_session (acl_main_t * am, int is_input, u32 sw_if_index)
 static u64
 acl_fa_get_list_head_expiry_time(acl_main_t *am, acl_fa_per_worker_data_t *pw, u64 now, u16 thread_index, int timeout_type)
 {
-  if (~0 == pw->fa_conn_list_head[timeout_type]) {
+  fa_session_t *sess = get_session_ptr(am, thread_index, pw->fa_conn_list_head[timeout_type]);
+  /*
+   * We can not check just the index here because inbetween the worker thread might
+   * dequeue the connection from the head just as we are about to check it.
+   */
+  if (!is_valid_session_ptr(am, thread_index, sess)) {
     return ~0LL; // infinity.
   } else {
-    fa_session_t *sess = get_session_ptr(am, thread_index, pw->fa_conn_list_head[timeout_type]);
     u64 timeout_time =
               sess->link_enqueue_time + fa_session_get_list_timeout (am, sess);
     return timeout_time;
@@ -789,6 +516,7 @@ acl_fa_check_idle_sessions(acl_main_t *am, u16 thread_index, u64 now)
            && (acl_fa_conn_time_to_check(am, pw, now, thread_index,
                                          pw->fa_conn_list_head[tt]))) {
        fsid.session_index = pw->fa_conn_list_head[tt];
+        elog_acl_maybe_trace_X2(am, "acl_fa_check_idle_sessions: expire session %d on thread %d", "i4i4", (u32)fsid.session_index, (u32)thread_index);
        vec_add1(pw->expired, fsid.session_index);
        acl_fa_conn_list_delete_session(am, fsid);
       }
@@ -808,8 +536,8 @@ acl_fa_check_idle_sessions(acl_main_t *am, u16 thread_index, u64 now)
        if ((now < sess_timeout_time) && (0 == clib_bitmap_get(pw->pending_clear_sw_if_index_bitmap, sw_if_index)))
          {
 #ifdef FA_NODE_VERBOSE_DEBUG
-           clib_warning ("ACL_FA_NODE_CLEAN: Restarting timer for session %d",
-              (int) session_index);
+           clib_warning ("ACL_FA_NODE_CLEAN: Restarting timer for session %d, sw_if_index %d",
+              (int) fsid.session_index, sess->sw_if_index);
 #endif
            /* There was activity on the session, so the idle timeout
               has not passed. Enqueue for another time period. */
@@ -820,8 +548,8 @@ acl_fa_check_idle_sessions(acl_main_t *am, u16 thread_index, u64 now)
        else
          {
 #ifdef FA_NODE_VERBOSE_DEBUG
-           clib_warning ("ACL_FA_NODE_CLEAN: Deleting session %d",
-              (int) session_index);
+           clib_warning ("ACL_FA_NODE_CLEAN: Deleting session %d, sw_if_index %d",
+              (int) fsid.session_index, sess->sw_if_index);
 #endif
            acl_fa_delete_session (am, sw_if_index, fsid);
            pw->cnt_deleted_sessions++;
@@ -859,7 +587,7 @@ acl_fa_try_recycle_session (acl_main_t * am, int is_input, u16 thread_index, u32
   }
 }
 
-static void
+static fa_session_t *
 acl_fa_add_session (acl_main_t * am, int is_input, u32 sw_if_index, u64 now,
                    fa_5tuple_t * p5tuple)
 {
@@ -867,6 +595,7 @@ acl_fa_add_session (acl_main_t * am, int is_input, u32 sw_if_index, u64 now,
   clib_bihash_kv_40_8_t kv;
   fa_full_session_id_t f_sess_id;
   uword thread_index = os_get_thread_index();
+  void *oldheap = clib_mem_set_heap(am->acl_mheap);
   acl_fa_per_worker_data_t *pw = &am->per_worker_data[thread_index];
 
   f_sess_id.thread_index = thread_index;
@@ -893,27 +622,23 @@ acl_fa_add_session (acl_main_t * am, int is_input, u32 sw_if_index, u64 now,
 
 
 
-  if (!acl_fa_ifc_has_sessions (am, sw_if_index))
-    {
-      acl_fa_ifc_init_sessions (am, sw_if_index);
-    }
-
+  ASSERT(am->fa_sessions_hash_is_initialized == 1);
   BV (clib_bihash_add_del) (&am->fa_sessions_hash,
                            &kv, 1);
   acl_fa_conn_list_add_session(am, f_sess_id, now);
 
-  vec_validate (am->fa_session_adds_by_sw_if_index, sw_if_index);
-  am->fa_session_adds_by_sw_if_index[sw_if_index]++;
+  vec_validate (pw->fa_session_adds_by_sw_if_index, sw_if_index);
+  clib_mem_set_heap (oldheap);
+  pw->fa_session_adds_by_sw_if_index[sw_if_index]++;
   clib_smp_atomic_add(&am->fa_session_total_adds, 1);
+  return sess;
 }
 
 static int
 acl_fa_find_session (acl_main_t * am, u32 sw_if_index0, fa_5tuple_t * p5tuple,
                     clib_bihash_kv_40_8_t * pvalue_sess)
 {
-  return (BV (clib_bihash_search)
-         (&am->fa_sessions_hash, &p5tuple->kv,
-          pvalue_sess) == 0);
+  return (clib_bihash_search_40_8 (&am->fa_sessions_hash, &p5tuple->kv, pvalue_sess) == 0);
 }
 
 
@@ -931,7 +656,6 @@ acl_fa_node_fn (vlib_main_t * vm,
   u32 pkts_acl_permit = 0;
   u32 pkts_restart_session_timer = 0;
   u32 trace_bitmap = 0;
-  u32 feature_bitmap0;
   acl_main_t *am = &acl_main;
   fa_5tuple_t fa_5tuple, kv_sess;
   clib_bihash_kv_40_8_t value_sess;
@@ -958,10 +682,13 @@ acl_fa_node_fn (vlib_main_t * vm,
          u32 next0 = 0;
          u8 action = 0;
          u32 sw_if_index0;
+         u32 lc_index0;
          int acl_check_needed = 1;
          u32 match_acl_in_index = ~0;
+         u32 match_acl_pos = ~0;
          u32 match_rule_index = ~0;
          u8 error0 = 0;
+         u32 valid_new_sess;
 
          /* speculatively enqueue b0 to the current next frame */
          bi0 = from[0];
@@ -977,29 +704,31 @@ acl_fa_node_fn (vlib_main_t * vm,
            sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
          else
            sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
-         if (is_l2_path)
-           feature_bitmap0 = vnet_buffer (b0)->l2.feature_bitmap;
 
+         if (is_input)
+           lc_index0 = am->input_lc_index_by_sw_if_index[sw_if_index0];
+         else
+           lc_index0 = am->output_lc_index_by_sw_if_index[sw_if_index0];
          /*
           * Extract the L3/L4 matching info into a 5-tuple structure,
           * then create a session key whose layout is independent on forward or reverse
           * direction of the packet.
           */
 
-         acl_fill_5tuple (am, b0, is_ip6, is_input, is_l2_path, &fa_5tuple);
+         acl_plugin_fill_5tuple_inline (lc_index0, b0, is_ip6, is_input, is_l2_path, (fa_5tuple_opaque_t *)&fa_5tuple);
           fa_5tuple.l4.lsb_of_sw_if_index = sw_if_index0 & 0xffff;
-         acl_make_5tuple_session_key (is_input, &fa_5tuple, &kv_sess);
-         fa_5tuple.pkt.sw_if_index = sw_if_index0;
+         fa_5tuple.pkt.lc_index = lc_index0;
+         valid_new_sess = acl_make_5tuple_session_key (am, is_input, is_ip6, sw_if_index0,  &fa_5tuple, &kv_sess);
           fa_5tuple.pkt.is_ip6 = is_ip6;
-          fa_5tuple.pkt.is_input = is_input;
+          // XXDEL fa_5tuple.pkt.is_input = is_input;
           fa_5tuple.pkt.mask_type_index_lsb = ~0;
 #ifdef FA_NODE_VERBOSE_DEBUG
          clib_warning
-           ("ACL_FA_NODE_DBG: session 5-tuple %016llx %016llx %016llx %016llx %016llx %016llx",
+           ("ACL_FA_NODE_DBG: session 5-tuple %016llx %016llx %016llx %016llx %016llx %016llx",
             kv_sess.kv.key[0], kv_sess.kv.key[1], kv_sess.kv.key[2],
             kv_sess.kv.key[3], kv_sess.kv.key[4], kv_sess.kv.value);
          clib_warning
-           ("ACL_FA_NODE_DBG: packet 5-tuple %016llx %016llx %016llx %016llx %016llx %016llx",
+           ("ACL_FA_NODE_DBG: packet 5-tuple %016llx %016llx %016llx %016llx %016llx %016llx",
             fa_5tuple.kv.key[0], fa_5tuple.kv.key[1], fa_5tuple.kv.key[2],
             fa_5tuple.kv.key[3], fa_5tuple.kv.key[4], fa_5tuple.kv.value);
 #endif
@@ -1058,9 +787,9 @@ acl_fa_node_fn (vlib_main_t * vm,
 
          if (acl_check_needed)
            {
-             action =
-               multi_acl_match_5tuple (sw_if_index0, &fa_5tuple, is_l2_path,
-                                      is_ip6, is_input, &match_acl_in_index,
+              action = 0; /* deny by default */
+             acl_plugin_match_5tuple_inline (lc_index0, (fa_5tuple_opaque_t *)&fa_5tuple,
+                                      is_ip6, &action, &match_acl_pos, &match_acl_in_index,
                                       &match_rule_index, &trace_bitmap);
              error0 = action;
              if (1 == action)
@@ -1072,9 +801,21 @@ acl_fa_node_fn (vlib_main_t * vm,
 
                  if (acl_fa_can_add_session (am, is_input, sw_if_index0))
                    {
-                      acl_fa_add_session (am, is_input, sw_if_index0, now,
-                                         &kv_sess);
-                     pkts_new_session += 1;
+                      if (PREDICT_TRUE (valid_new_sess)) {
+                        fa_session_t *sess = acl_fa_add_session (am, is_input,
+                                                                 sw_if_index0,
+                                                                 now, &kv_sess);
+                        acl_fa_track_session (am, is_input, sw_if_index0, now,
+                                              sess, &fa_5tuple);
+                        pkts_new_session += 1;
+                      } else {
+                        /*
+                         *  ICMP packets with non-icmp_valid_new type will be
+                         *  forwared without being dropped.
+                         */
+                        action = 1;
+                        pkts_acl_permit += 1;
+                      }
                    }
                  else
                    {
@@ -1089,18 +830,20 @@ acl_fa_node_fn (vlib_main_t * vm,
          if (action > 0)
            {
              if (is_l2_path)
-               next0 =
-                 feat_bitmap_get_next_node_index (l2_feat_next_node_index,
-                                                  feature_bitmap0);
+               next0 = vnet_l2_feature_next (b0, l2_feat_next_node_index, 0);
              else
                vnet_feature_next (sw_if_index0, &next0, b0);
            }
+#ifdef FA_NODE_VERBOSE_DEBUG
+          clib_warning("ACL_FA_NODE_DBG: sw_if_index %d lc_index %d action %d acl_index %d rule_index %d", sw_if_index0, lc_index0, action, match_acl_in_index, match_rule_index);
+#endif
 
          if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
                             && (b0->flags & VLIB_BUFFER_IS_TRACED)))
            {
              acl_fa_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
              t->sw_if_index = sw_if_index0;
+             t->lc_index = lc_index0;
              t->next_index = next0;
              t->match_acl_in_index = match_acl_in_index;
              t->match_rule_index = match_rule_index;
@@ -1270,9 +1013,7 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
    u16 thread_index = os_get_thread_index ();
    acl_fa_per_worker_data_t *pw = &am->per_worker_data[thread_index];
    int num_expired;
-#ifdef FA_NODE_VERBOSE_DEBUG
-   clib_warning("\nacl_fa_worker_conn_cleaner: thread index %d now %lu\n\n", thread_index, now);
-#endif
+   elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner interrupt: now %lu", "i8", now);
    /* allow another interrupt to be queued */
    pw->interrupt_is_pending = 0;
    if (pw->clear_in_process) {
@@ -1290,9 +1031,7 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
         */
        if ((pw->pending_clear_sw_if_index_bitmap == 0)
            || (pw->serviced_sw_if_index_bitmap == 0)) {
-#ifdef FA_NODE_VERBOSE_DEBUG
-         clib_warning("WORKER-CLEAR: someone tried to call clear, but one of the bitmaps are empty");
-#endif
+         elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner: now %lu, someone tried to call clear but one of the bitmaps are empty", "i8", now);
         clib_bitmap_zero(pw->pending_clear_sw_if_index_bitmap);
        } else {
 #ifdef FA_NODE_VERBOSE_DEBUG
@@ -1306,9 +1045,7 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
 
        if (clib_bitmap_is_zero(pw->pending_clear_sw_if_index_bitmap)) {
          /* if the cross-section is a zero vector, no need to do anything. */
-#ifdef FA_NODE_VERBOSE_DEBUG
-         clib_warning("WORKER: clearing done - nothing to do");
-#endif
+         elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner: now %lu, clearing done, nothing to do", "i8", now);
          pw->clear_in_process = 0;
        } else {
 #ifdef FA_NODE_VERBOSE_DEBUG
@@ -1316,6 +1053,7 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
                       format_bitmap_hex, pw->pending_clear_sw_if_index_bitmap,
                       format_bitmap_hex, pw->serviced_sw_if_index_bitmap);
 #endif
+         elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner: swiping until %lu", "i8", now);
          /* swipe through the connection lists until enqueue timestamps become above "now" */
          pw->swipe_end_time = now;
        }
@@ -1323,18 +1061,15 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
    }
    num_expired = acl_fa_check_idle_sessions(am, thread_index, now);
    // clib_warning("WORKER-CLEAR: checked %d sessions (clear_in_progress: %d)", num_expired, pw->clear_in_process);
+   elog_acl_maybe_trace_X2(am, "acl_fa_worker_conn_cleaner: checked %d sessions (clear_in_process: %d)", "i4i4", (u32)num_expired, (u32)pw->clear_in_process);
    if (pw->clear_in_process) {
      if (0 == num_expired) {
        /* we were clearing but we could not process any more connections. time to stop. */
        clib_bitmap_zero(pw->pending_clear_sw_if_index_bitmap);
        pw->clear_in_process = 0;
-#ifdef FA_NODE_VERBOSE_DEBUG
-       clib_warning("WORKER: clearing done, all done");
-#endif
+       elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner: now %lu, clearing done - all done", "i8", now);
      } else {
-#ifdef FA_NODE_VERBOSE_DEBUG
-       clib_warning("WORKER-CLEAR: more work to do, raising interrupt");
-#endif
+       elog_acl_maybe_trace_X1(am, "acl_fa_worker_conn_cleaner: now %lu, more work to do - requesting interrupt", "i8", now);
        /* should continue clearing.. So could they please sent an interrupt again? */
        pw->interrupt_is_needed = 1;
      }
@@ -1342,15 +1077,19 @@ acl_fa_worker_conn_cleaner_process(vlib_main_t * vm,
      if (num_expired >= am->fa_max_deleted_sessions_per_interval) {
        /* there was too much work, we should get an interrupt ASAP */
        pw->interrupt_is_needed = 1;
+       pw->interrupt_is_unwanted = 0;
      } else if (num_expired <= am->fa_min_deleted_sessions_per_interval) {
        /* signal that they should trigger us less */
+       pw->interrupt_is_needed = 0;
        pw->interrupt_is_unwanted = 1;
      } else {
        /* the current rate of interrupts is ok */
        pw->interrupt_is_needed = 0;
        pw->interrupt_is_unwanted = 0;
      }
+     elog_acl_maybe_trace_X3(am, "acl_fa_worker_conn_cleaner: now %lu, interrupt needed: %u, interrupt unwanted: %u", "i8i4i4", now, ((u32)pw->interrupt_is_needed), ((u32)pw->interrupt_is_unwanted));
    }
+   pw->interrupt_generation = am->fa_interrupt_generation;
    return 0;
 }
 
@@ -1359,11 +1098,12 @@ send_one_worker_interrupt (vlib_main_t * vm, acl_main_t *am, int thread_index)
 {
   acl_fa_per_worker_data_t *pw = &am->per_worker_data[thread_index];
   if (!pw->interrupt_is_pending) {
+    pw->interrupt_is_pending = 1;
     vlib_node_set_interrupt_pending (vlib_mains[thread_index],
                   acl_fa_worker_session_cleaner_process_node.index);
-    pw->interrupt_is_pending = 1;
+    elog_acl_maybe_trace_X1(am, "send_one_worker_interrupt: send interrupt to worker %d", "i4", ((u32)thread_index));
     /* if the interrupt was requested, mark that done. */
-    pw->interrupt_is_needed = 0;
+    /* pw->interrupt_is_needed = 0; */
   }
 }
 
@@ -1373,7 +1113,7 @@ send_interrupts_to_workers (vlib_main_t * vm, acl_main_t *am)
   int i;
   /* Can't use vec_len(am->per_worker_data) since the threads might not have come up yet; */
   int n_threads = vec_len(vlib_mains);
-  for (i = n_threads > 1 ? 1 : 0; i < n_threads; i++) {
+  for (i = 0; i < n_threads; i++) {
     send_one_worker_interrupt(vm, am, i);
   }
 }
@@ -1394,7 +1134,7 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
 
   am->fa_current_cleaner_timer_wait_interval = max_timer_wait_interval;
   am->fa_cleaner_node_index = acl_fa_session_cleaner_process_node.index;
-
+  am->fa_interrupt_generation = 1;
   while (1)
     {
       now = clib_cpu_time_now ();
@@ -1419,9 +1159,8 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
         for(tt = 0; tt < vec_len(pw->fa_conn_list_head); tt++) {
           u64 head_expiry = acl_fa_get_list_head_expiry_time(am, pw, now, ti, tt);
           if ((head_expiry < next_expire) && !pw->interrupt_is_pending) {
-#ifdef FA_NODE_VERBOSE_DEBUG
-            clib_warning("Head expiry: %lu, now: %lu, next_expire: %lu (worker: %d, tt: %d)", head_expiry, now, next_expire, ti, tt);
-#endif
+            elog_acl_maybe_trace_X3(am, "acl_fa_session_cleaner_process: now %lu, worker: %d tt: %d", "i8i2i2", now, ti, tt);
+            elog_acl_maybe_trace_X2(am, "acl_fa_session_cleaner_process: head expiry: %lu, is earlier than curr next expire: %lu", "i8i8", head_expiry, next_expire);
             next_expire = head_expiry;
          }
           if (~0 != pw->fa_conn_list_head[tt]) {
@@ -1430,10 +1169,11 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
         }
       }
 
-      /* If no pending connections then no point in timing out */
-      if (!has_pending_conns)
+      /* If no pending connections and no ACL applied then no point in timing out */
+      if (!has_pending_conns && (0 == am->fa_total_enabled_count))
         {
           am->fa_cleaner_cnt_wait_without_timeout++;
+          elog_acl_maybe_trace_X1(am, "acl_conn_cleaner: now %lu entering wait without timeout", "i8", now);
           (void) vlib_process_wait_for_event (vm);
           event_type = vlib_process_get_events (vm, &event_data);
         }
@@ -1448,6 +1188,7 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
          else
            {
               am->fa_cleaner_cnt_wait_with_timeout++;
+              elog_acl_maybe_trace_X2(am, "acl_conn_cleaner: now %lu entering wait with timeout %.6f sec", "i8f8", now, timeout);
              (void) vlib_process_wait_for_event_or_clock (vm, timeout);
              event_type = vlib_process_get_events (vm, &event_data);
            }
@@ -1466,17 +1207,12 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
             uword *clear_sw_if_index_bitmap = 0;
            uword *sw_if_index0;
             int clear_all = 0;
-#ifdef FA_NODE_VERBOSE_DEBUG
-           clib_warning("ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX received");
-#endif
+            now = clib_cpu_time_now ();
+            elog_acl_maybe_trace_X1(am, "acl_fa_session_cleaner_process: now %lu, received ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX", "i8", now);
            vec_foreach (sw_if_index0, event_data)
            {
               am->fa_cleaner_cnt_delete_by_sw_index++;
-#ifdef FA_NODE_VERBOSE_DEBUG
-             clib_warning
-               ("ACL_FA_NODE_CLEAN: ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX: %d",
-                *sw_if_index0);
-#endif
+              elog_acl_maybe_trace_X1(am, "acl_fa_session_cleaner_process: ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX %d", "i4", *sw_if_index0);
               if (*sw_if_index0 == ~0)
                 {
                   clear_all = 1;
@@ -1496,9 +1232,7 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
               CLIB_MEMORY_BARRIER ();
              while (pw0->clear_in_process) {
                 CLIB_MEMORY_BARRIER ();
-#ifdef FA_NODE_VERBOSE_DEBUG
-                clib_warning("ACL_FA_NODE_CLEAN: waiting previous cleaning cycle to finish on %d...", pw0 - am->per_worker_data);
-#endif
+                elog_acl_maybe_trace_X1(am, "ACL_FA_NODE_CLEAN: waiting previous cleaning cycle to finish on %d", "i4", (u32)(pw0 - am->per_worker_data));
                 vlib_process_suspend(vm, 0.0001);
                 if (pw0->interrupt_is_needed) {
                   send_one_worker_interrupt(vm, am, (pw0 - am->per_worker_data));
@@ -1530,9 +1264,7 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
               CLIB_MEMORY_BARRIER ();
              while (pw0->clear_in_process) {
                 CLIB_MEMORY_BARRIER ();
-#ifdef FA_NODE_VERBOSE_DEBUG
-                clib_warning("ACL_FA_NODE_CLEAN: waiting for my cleaning cycle to finish on %d...", pw0 - am->per_worker_data);
-#endif
+                elog_acl_maybe_trace_X1(am, "ACL_FA_NODE_CLEAN: waiting for my cleaning cycle to finish on %d", "i4", (u32)(pw0 - am->per_worker_data));
                 vlib_process_suspend(vm, 0.0001);
                 if (pw0->interrupt_is_needed) {
                   send_one_worker_interrupt(vm, am, (pw0 - am->per_worker_data));
@@ -1563,6 +1295,23 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
       if (event_data)
        _vec_len (event_data) = 0;
 
+      /*
+       * If the interrupts were not processed yet, ensure we wait a bit,
+       * but up to a point.
+       */
+      int need_more_wait = 0;
+      int max_wait_cycles = 100;
+      do {
+        need_more_wait = 0;
+        vec_foreach(pw0, am->per_worker_data) {
+          if (pw0->interrupt_generation != am->fa_interrupt_generation) {
+            need_more_wait = 1;
+          }
+        }
+        if (need_more_wait) {
+          vlib_process_suspend(vm, 0.0001);
+        }
+      } while (need_more_wait && (--max_wait_cycles > 0));
 
       int interrupts_needed = 0;
       int interrupts_unwanted = 0;
@@ -1580,12 +1329,15 @@ acl_fa_session_cleaner_process (vlib_main_t * vm, vlib_node_runtime_t * rt,
       if (interrupts_needed) {
         /* they need more interrupts, do less waiting around next time */
         am->fa_current_cleaner_timer_wait_interval /= 2;
+        /* never go into zero-wait either though - we need to give the space to others */
+        am->fa_current_cleaner_timer_wait_interval += 1; 
       } else if (interrupts_unwanted) {
         /* slowly increase the amount of sleep up to a limit */
         if (am->fa_current_cleaner_timer_wait_interval < max_timer_wait_interval)
           am->fa_current_cleaner_timer_wait_interval += cpu_cps * am->fa_cleaner_wait_time_increment;
       }
       am->fa_cleaner_cnt_event_cycles++;
+      am->fa_interrupt_generation++;
     }
   /* NOT REACHED */
   return 0;
@@ -1596,22 +1348,39 @@ void
 acl_fa_enable_disable (u32 sw_if_index, int is_input, int enable_disable)
 {
   acl_main_t *am = &acl_main;
+  if (enable_disable) {
+    acl_fa_verify_init_sessions(am);
+    am->fa_total_enabled_count++;
+    void *oldheap = clib_mem_set_heap (am->vlib_main->heap_base);
+    vlib_process_signal_event (am->vlib_main, am->fa_cleaner_node_index,
+                                 ACL_FA_CLEANER_RESCHEDULE, 0);
+    clib_mem_set_heap (oldheap);
+  } else {
+    am->fa_total_enabled_count--;
+  }
+
   if (is_input)
     {
+      ASSERT(clib_bitmap_get(am->fa_in_acl_on_sw_if_index, sw_if_index) != enable_disable);
+      void *oldheap = clib_mem_set_heap (am->vlib_main->heap_base);
       vnet_feature_enable_disable ("ip4-unicast", "acl-plugin-in-ip4-fa",
                                   sw_if_index, enable_disable, 0, 0);
       vnet_feature_enable_disable ("ip6-unicast", "acl-plugin-in-ip6-fa",
                                   sw_if_index, enable_disable, 0, 0);
+      clib_mem_set_heap (oldheap);
       am->fa_in_acl_on_sw_if_index =
        clib_bitmap_set (am->fa_in_acl_on_sw_if_index, sw_if_index,
                         enable_disable);
     }
   else
     {
+      ASSERT(clib_bitmap_get(am->fa_out_acl_on_sw_if_index, sw_if_index) != enable_disable);
+      void *oldheap = clib_mem_set_heap (am->vlib_main->heap_base);
       vnet_feature_enable_disable ("ip4-output", "acl-plugin-out-ip4-fa",
                                   sw_if_index, enable_disable, 0, 0);
       vnet_feature_enable_disable ("ip6-output", "acl-plugin-out-ip6-fa",
                                   sw_if_index, enable_disable, 0, 0);
+      clib_mem_set_heap (oldheap);
       am->fa_out_acl_on_sw_if_index =
        clib_bitmap_set (am->fa_out_acl_on_sw_if_index, sw_if_index,
                         enable_disable);
@@ -1622,9 +1391,11 @@ acl_fa_enable_disable (u32 sw_if_index, int is_input, int enable_disable)
 #ifdef FA_NODE_VERBOSE_DEBUG
       clib_warning("ENABLE-DISABLE: clean the connections on interface %d", sw_if_index);
 #endif
+      void *oldheap = clib_mem_set_heap (am->vlib_main->heap_base);
       vlib_process_signal_event (am->vlib_main, am->fa_cleaner_node_index,
                                 ACL_FA_CLEANER_DELETE_BY_SW_IF_INDEX,
                                 sw_if_index);
+      clib_mem_set_heap (oldheap);
     }
 }