text: /*
   * node.c - ipfix probe graph node
   *
   * Copyright (c) 2017 Cisco and/or its affiliates.
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at:
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  #include <vlib/vlib.h>
  #include <vnet/vnet.h>
  #include <vnet/pg/pg.h>
  #include <vppinfra/crc32.h>
  #include <vppinfra/error.h>
  #include <flowprobe/flowprobe.h>
  #include <vnet/ip/ip6_packet.h>
  #include <vlibmemory/api.h>
  
  static void flowprobe_export_entry (vlib_main_t * vm, flowprobe_entry_t * e);
  
  /**
   * @file node.c
   * flow record generator graph node
   */
  
  typedef struct
  {
    /** interface handle */
    u32 rx_sw_if_index;
    u32 tx_sw_if_index;
    /** packet timestamp */
    u64 timestamp;
    /** size of the buffer */
    u16 buffer_size;
  
    /** L2 information */
    u8 src_mac[6];
    u8 dst_mac[6];
    /** Ethertype */
    u16 ethertype;
  
    /** L3 information */
    ip46_address_t src_address;
    ip46_address_t dst_address;
    u8 protocol;
    u8 tos;
  
    /** L4 information */
    u16 src_port;
    u16 dst_port;
  
    flowprobe_variant_t which;
  } flowprobe_trace_t;
  
  static char *flowprobe_variant_strings[] = {
    [FLOW_VARIANT_IP4] = "IP4",
    [FLOW_VARIANT_IP6] = "IP6",
    [FLOW_VARIANT_L2] = "L2",
    [FLOW_VARIANT_L2_IP4] = "L2-IP4",
    [FLOW_VARIANT_L2_IP6] = "L2-IP6",
  };
  
  /* packet trace format function */
  static u8 *
  format_flowprobe_trace (u8 * s, va_list * args)
  {
    CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
    CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
    flowprobe_trace_t *t = va_arg (*args, flowprobe_trace_t *);
    u32 indent = format_get_indent (s);
  
    s = format (s,
  	      "FLOWPROBE[%s]: rx_sw_if_index %d, tx_sw_if_index %d, "
  	      "timestamp %lld, size %d", flowprobe_variant_strings[t->which],
  	      t->rx_sw_if_index, t->tx_sw_if_index,
  	      t->timestamp, t->buffer_size);
  
    if (t->which == FLOW_VARIANT_L2)
      s = format (s, "\n%U -> %U", format_white_space, indent,
  		format_ethernet_address, &t->src_mac,
  		format_ethernet_address, &t->dst_mac);
  
    if (t->protocol > 0
        && (t->which == FLOW_VARIANT_L2_IP4 || t->which == FLOW_VARIANT_IP4
  	  || t->which == FLOW_VARIANT_L2_IP6 || t->which == FLOW_VARIANT_IP6))
      s =
        format (s, "\n%U%U: %U -> %U", format_white_space, indent,
  	      format_ip_protocol, t->protocol, format_ip46_address,
  	      &t->src_address, IP46_TYPE_ANY, format_ip46_address,
  	      &t->dst_address, IP46_TYPE_ANY);
    return s;
  }
  
  vlib_node_registration_t flowprobe_ip4_node;
  vlib_node_registration_t flowprobe_ip6_node;
  vlib_node_registration_t flowprobe_l2_node;
  
  /* No counters at the moment */
  #define foreach_flowprobe_error			\
  _(COLLISION, "Hash table collisions")		\
  _(BUFFER, "Buffer allocation error")		\
  _(EXPORTED_PACKETS, "Exported packets")		\
  _(INPATH, "Exported packets in path")
  
  typedef enum
  {
  #define _(sym,str) FLOWPROBE_ERROR_##sym,
    foreach_flowprobe_error
  #undef _
      FLOWPROBE_N_ERROR,
  } flowprobe_error_t;
  
  static char *flowprobe_error_strings[] = {
  #define _(sym,string) string,
    foreach_flowprobe_error
  #undef _
  };
  
  typedef enum
  {
    FLOWPROBE_NEXT_DROP,
    FLOWPROBE_NEXT_IP4_LOOKUP,
    FLOWPROBE_N_NEXT,
  } flowprobe_next_t;
  
  #define FLOWPROBE_NEXT_NODES {					\
      [FLOWPROBE_NEXT_DROP] = "error-drop",			\
      [FLOWPROBE_NEXT_IP4_LOOKUP] = "ip4-lookup",		\
  }
  
  static inline flowprobe_variant_t
  flowprobe_get_variant (flowprobe_variant_t which,
  		       flowprobe_record_t flags, u16 ethertype)
  {
    if (which == FLOW_VARIANT_L2
        && (flags & FLOW_RECORD_L3 || flags & FLOW_RECORD_L4))
      return ethertype == ETHERNET_TYPE_IP6 ? FLOW_VARIANT_L2_IP6 : ethertype ==
        ETHERNET_TYPE_IP4 ? FLOW_VARIANT_L2_IP4 : FLOW_VARIANT_L2;
    return which;
  }
  
  /*
   * NTP rfc868 : 2 208 988 800 corresponds to 00:00  1 Jan 1970 GMT
   */
  #define NTP_TIMESTAMP 2208988800LU
  
  static inline u32
  flowprobe_common_add (vlib_buffer_t * to_b, flowprobe_entry_t * e, u16 offset)
  {
    u16 start = offset;
  
    /* Ingress interface */
    u32 rx_if = clib_host_to_net_u32 (e->key.rx_sw_if_index);
    clib_memcpy_fast (to_b->data + offset, &rx_if, sizeof (rx_if));
    offset += sizeof (rx_if);
  
    /* Egress interface */
    u32 tx_if = clib_host_to_net_u32 (e->key.tx_sw_if_index);
    clib_memcpy_fast (to_b->data + offset, &tx_if, sizeof (tx_if));
    offset += sizeof (tx_if);
  
    /* packet delta count */
    u64 packetdelta = clib_host_to_net_u64 (e->packetcount);
    clib_memcpy_fast (to_b->data + offset, &packetdelta, sizeof (u64));
    offset += sizeof (u64);
  
    /* flowStartNanoseconds */
    u32 t = clib_host_to_net_u32 (e->flow_start.sec + NTP_TIMESTAMP);
    clib_memcpy_fast (to_b->data + offset, &t, sizeof (u32));
    offset += sizeof (u32);
    t = clib_host_to_net_u32 (e->flow_start.nsec);
    clib_memcpy_fast (to_b->data + offset, &t, sizeof (u32));
    offset += sizeof (u32);
  
    /* flowEndNanoseconds */
    t = clib_host_to_net_u32 (e->flow_end.sec + NTP_TIMESTAMP);
    clib_memcpy_fast (to_b->data + offset, &t, sizeof (u32));
    offset += sizeof (u32);
    t = clib_host_to_net_u32 (e->flow_end.nsec);
    clib_memcpy_fast (to_b->data + offset, &t, sizeof (u32));
    offset += sizeof (u32);
  
    return offset - start;
  }
  
  static inline u32
  flowprobe_l2_add (vlib_buffer_t * to_b, flowprobe_entry_t * e, u16 offset)
  {
    u16 start = offset;
  
    /* src mac address */
    clib_memcpy_fast (to_b->data + offset, &e->key.src_mac, 6);
    offset += 6;
  
    /* dst mac address */
    clib_memcpy_fast (to_b->data + offset, &e->key.dst_mac, 6);
    offset += 6;
  
    /* ethertype */
    clib_memcpy_fast (to_b->data + offset, &e->key.ethertype, 2);
    offset += 2;
  
    return offset - start;
  }
  
  static inline u32
  flowprobe_l3_ip6_add (vlib_buffer_t * to_b, flowprobe_entry_t * e, u16 offset)
  {
    u16 start = offset;
  
    /* ip6 src address */
    clib_memcpy_fast (to_b->data + offset, &e->key.src_address,
  		    sizeof (ip6_address_t));
    offset += sizeof (ip6_address_t);
  
    /* ip6 dst address */
    clib_memcpy_fast (to_b->data + offset, &e->key.dst_address,
  		    sizeof (ip6_address_t));
    offset += sizeof (ip6_address_t);
  
    /* Protocol */
    to_b->data[offset++] = e->key.protocol;
  
    /* octetDeltaCount */
    u64 octetdelta = clib_host_to_net_u64 (e->octetcount);
    clib_memcpy_fast (to_b->data + offset, &octetdelta, sizeof (u64));
    offset += sizeof (u64);
  
    return offset - start;
  }
  
  static inline u32
  flowprobe_l3_ip4_add (vlib_buffer_t * to_b, flowprobe_entry_t * e, u16 offset)
  {
    u16 start = offset;
  
    /* ip4 src address */
    clib_memcpy_fast (to_b->data + offset, &e->key.src_address.ip4,
  		    sizeof (ip4_address_t));
    offset += sizeof (ip4_address_t);
  
    /* ip4 dst address */
    clib_memcpy_fast (to_b->data + offset, &e->key.dst_address.ip4,
  		    sizeof (ip4_address_t));
    offset += sizeof (ip4_address_t);
  
    /* Protocol */
    to_b->data[offset++] = e->key.protocol;
  
    /* octetDeltaCount */
    u64 octetdelta = clib_host_to_net_u64 (e->octetcount);
    clib_memcpy_fast (to_b->data + offset, &octetdelta, sizeof (u64));
    offset += sizeof (u64);
  
    return offset - start;
  }
  
  static inline u32
  flowprobe_l4_add (vlib_buffer_t * to_b, flowprobe_entry_t * e, u16 offset)
  {
    u16 start = offset;
  
    /* src port */
    clib_memcpy_fast (to_b->data + offset, &e->key.src_port, 2);
    offset += 2;
  
    /* dst port */
    clib_memcpy_fast (to_b->data + offset, &e->key.dst_port, 2);
    offset += 2;
  
    /* tcp control bits */
    u16 control_bits = htons (e->prot.tcp.flags);
    clib_memcpy_fast (to_b->data + offset, &control_bits, 2);
    offset += 2;
  
    return offset - start;
  }
  
  static inline u32
  flowprobe_hash (flowprobe_key_t * k)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    u32 h = 0;
  
  #ifdef clib_crc32c_uses_intrinsics
    h = clib_crc32c ((u8 *) k, sizeof (*k));
  #else
    int i;
    u64 tmp = 0;
    for (i = 0; i < sizeof (*k) / 8; i++)
      tmp ^= ((u64 *) k)[i];
  
    h = clib_xxhash (tmp);
  #endif
  
    return h >> (32 - fm->ht_log2len);
  }
  
  flowprobe_entry_t *
  flowprobe_lookup (u32 my_cpu_number, flowprobe_key_t * k, u32 * poolindex,
  		  bool * collision)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    flowprobe_entry_t *e;
    u32 h;
  
    h = (fm->active_timer) ? flowprobe_hash (k) : 0;
  
    /* Lookup in the flow state pool */
    *poolindex = fm->hash_per_worker[my_cpu_number][h];
    if (*poolindex != ~0)
      {
        e = pool_elt_at_index (fm->pool_per_worker[my_cpu_number], *poolindex);
        if (e)
  	{
  	  /* Verify key or report collision */
  	  if (memcmp (k, &e->key, sizeof (flowprobe_key_t)))
  	    *collision = true;
  	  return e;
  	}
      }
  
    return 0;
  }
  
  flowprobe_entry_t *
  flowprobe_create (u32 my_cpu_number, flowprobe_key_t * k, u32 * poolindex)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    u32 h;
  
    flowprobe_entry_t *e;
  
    /* Get my index */
    h = (fm->active_timer) ? flowprobe_hash (k) : 0;
  
    pool_get (fm->pool_per_worker[my_cpu_number], e);
    *poolindex = e - fm->pool_per_worker[my_cpu_number];
    fm->hash_per_worker[my_cpu_number][h] = *poolindex;
  
    e->key = *k;
  
    if (fm->passive_timer > 0)
      {
        e->passive_timer_handle = tw_timer_start_2t_1w_2048sl
  	(fm->timers_per_worker[my_cpu_number], *poolindex, 0,
  	 fm->passive_timer);
      }
    return e;
  }
  
  static inline void
  add_to_flow_record_state (vlib_main_t * vm, vlib_node_runtime_t * node,
  			  flowprobe_main_t * fm, vlib_buffer_t * b,
  			  timestamp_nsec_t timestamp, u16 length,
  			  flowprobe_variant_t which, flowprobe_trace_t * t)
  {
    if (fm->disabled)
      return;
  
    u32 my_cpu_number = vm->thread_index;
    u16 octets = 0;
  
    flowprobe_record_t flags = fm->context[which].flags;
    bool collect_ip4 = false, collect_ip6 = false;
    ASSERT (b);
    ethernet_header_t *eth = vlib_buffer_get_current (b);
    u16 ethertype = clib_net_to_host_u16 (eth->type);
    /* *INDENT-OFF* */
    flowprobe_key_t k = {};
    /* *INDENT-ON* */
    ip4_header_t *ip4 = 0;
    ip6_header_t *ip6 = 0;
    udp_header_t *udp = 0;
    tcp_header_t *tcp = 0;
    u8 tcp_flags = 0;
  
    if (flags & FLOW_RECORD_L3 || flags & FLOW_RECORD_L4)
      {
        collect_ip4 = which == FLOW_VARIANT_L2_IP4 || which == FLOW_VARIANT_IP4;
        collect_ip6 = which == FLOW_VARIANT_L2_IP6 || which == FLOW_VARIANT_IP6;
      }
  
    k.rx_sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
    k.tx_sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_TX];
  
    k.which = which;
  
    if (flags & FLOW_RECORD_L2)
      {
        clib_memcpy_fast (k.src_mac, eth->src_address, 6);
        clib_memcpy_fast (k.dst_mac, eth->dst_address, 6);
        k.ethertype = ethertype;
      }
    if (collect_ip6 && ethertype == ETHERNET_TYPE_IP6)
      {
        ip6 = (ip6_header_t *) (eth + 1);
        if (flags & FLOW_RECORD_L3)
  	{
  	  k.src_address.as_u64[0] = ip6->src_address.as_u64[0];
  	  k.src_address.as_u64[1] = ip6->src_address.as_u64[1];
  	  k.dst_address.as_u64[0] = ip6->dst_address.as_u64[0];
  	  k.dst_address.as_u64[1] = ip6->dst_address.as_u64[1];
  	}
        k.protocol = ip6->protocol;
        if (k.protocol == IP_PROTOCOL_UDP)
  	udp = (udp_header_t *) (ip6 + 1);
        else if (k.protocol == IP_PROTOCOL_TCP)
  	tcp = (tcp_header_t *) (ip6 + 1);
  
        octets = clib_net_to_host_u16 (ip6->payload_length)
  	+ sizeof (ip6_header_t);
      }
    if (collect_ip4 && ethertype == ETHERNET_TYPE_IP4)
      {
        ip4 = (ip4_header_t *) (eth + 1);
        if (flags & FLOW_RECORD_L3)
  	{
  	  k.src_address.ip4.as_u32 = ip4->src_address.as_u32;
  	  k.dst_address.ip4.as_u32 = ip4->dst_address.as_u32;
  	}
        k.protocol = ip4->protocol;
        if ((flags & FLOW_RECORD_L4) && k.protocol == IP_PROTOCOL_UDP)
  	udp = (udp_header_t *) (ip4 + 1);
        else if ((flags & FLOW_RECORD_L4) && k.protocol == IP_PROTOCOL_TCP)
  	tcp = (tcp_header_t *) (ip4 + 1);
  
        octets = clib_net_to_host_u16 (ip4->length);
      }
  
    if (udp)
      {
        k.src_port = udp->src_port;
        k.dst_port = udp->dst_port;
      }
    else if (tcp)
      {
        k.src_port = tcp->src_port;
        k.dst_port = tcp->dst_port;
        tcp_flags = tcp->flags;
      }
  
    if (t)
      {
        t->rx_sw_if_index = k.rx_sw_if_index;
        t->tx_sw_if_index = k.tx_sw_if_index;
        clib_memcpy_fast (t->src_mac, k.src_mac, 6);
        clib_memcpy_fast (t->dst_mac, k.dst_mac, 6);
        t->ethertype = k.ethertype;
        t->src_address.ip4.as_u32 = k.src_address.ip4.as_u32;
        t->dst_address.ip4.as_u32 = k.dst_address.ip4.as_u32;
        t->protocol = k.protocol;
        t->src_port = k.src_port;
        t->dst_port = k.dst_port;
        t->which = k.which;
      }
  
    flowprobe_entry_t *e = 0;
    f64 now = vlib_time_now (vm);
    if (fm->active_timer > 0)
      {
        u32 poolindex = ~0;
        bool collision = false;
  
        e = flowprobe_lookup (my_cpu_number, &k, &poolindex, &collision);
        if (collision)
  	{
  	  /* Flush data and clean up entry for reuse. */
  	  if (e->packetcount)
  	    flowprobe_export_entry (vm, e);
  	  e->key = k;
  	  e->flow_start = timestamp;
  	  vlib_node_increment_counter (vm, node->node_index,
  				       FLOWPROBE_ERROR_COLLISION, 1);
  	}
        if (!e)			/* Create new entry */
  	{
  	  e = flowprobe_create (my_cpu_number, &k, &poolindex);
  	  e->last_exported = now;
  	  e->flow_start = timestamp;
  	}
      }
    else
      {
        e = &fm->stateless_entry[my_cpu_number];
        e->key = k;
      }
  
    if (e)
      {
        /* Updating entry */
        e->packetcount++;
        e->octetcount += octets;
        e->last_updated = now;
        e->flow_end = timestamp;
        e->prot.tcp.flags |= tcp_flags;
        if (fm->active_timer == 0
  	  || (now > e->last_exported + fm->active_timer))
  	flowprobe_export_entry (vm, e);
      }
  }
  
  static u16
  flowprobe_get_headersize (void)
  {
    return sizeof (ip4_header_t) + sizeof (udp_header_t) +
      sizeof (ipfix_message_header_t) + sizeof (ipfix_set_header_t);
  }
  
  static void
  flowprobe_export_send (vlib_main_t * vm, vlib_buffer_t * b0,
  		       flowprobe_variant_t which)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    flow_report_main_t *frm = &flow_report_main;
    vlib_frame_t *f;
    ip4_ipfix_template_packet_t *tp;
    ipfix_set_header_t *s;
    ipfix_message_header_t *h;
    ip4_header_t *ip;
    udp_header_t *udp;
    flowprobe_record_t flags = fm->context[which].flags;
    u32 my_cpu_number = vm->thread_index;
  
    /* Fill in header */
    flow_report_stream_t *stream;
  
    /* Nothing to send */
    if (fm->context[which].next_record_offset_per_worker[my_cpu_number] <=
        flowprobe_get_headersize ())
      return;
  
    u32 i, index = vec_len (frm->streams);
    for (i = 0; i < index; i++)
      if (frm->streams[i].domain_id == 1)
        {
  	index = i;
  	break;
        }
    if (i == vec_len (frm->streams))
      {
        vec_validate (frm->streams, index);
        frm->streams[index].domain_id = 1;
      }
    stream = &frm->streams[index];
  
    tp = vlib_buffer_get_current (b0);
    ip = (ip4_header_t *) & tp->ip4;
    udp = (udp_header_t *) (ip + 1);
    h = (ipfix_message_header_t *) (udp + 1);
    s = (ipfix_set_header_t *) (h + 1);
  
    ip->ip_version_and_header_length = 0x45;
    ip->ttl = 254;
    ip->protocol = IP_PROTOCOL_UDP;
    ip->flags_and_fragment_offset = 0;
    ip->src_address.as_u32 = frm->src_address.as_u32;
    ip->dst_address.as_u32 = frm->ipfix_collector.as_u32;
    udp->src_port = clib_host_to_net_u16 (UDP_DST_PORT_ipfix);
    udp->dst_port = clib_host_to_net_u16 (UDP_DST_PORT_ipfix);
    udp->checksum = 0;
  
    /* FIXUP: message header export_time */
    h->export_time = (u32)
      (((f64) frm->unix_time_0) +
       (vlib_time_now (frm->vlib_main) - frm->vlib_time_0));
    h->export_time = clib_host_to_net_u32 (h->export_time);
    h->domain_id = clib_host_to_net_u32 (stream->domain_id);
  
    /* FIXUP: message header sequence_number */
    h->sequence_number = stream->sequence_number++;
    h->sequence_number = clib_host_to_net_u32 (h->sequence_number);
  
    s->set_id_length = ipfix_set_id_length (fm->template_reports[flags],
  					  b0->current_length -
  					  (sizeof (*ip) + sizeof (*udp) +
  					   sizeof (*h)));
    h->version_length = version_length (b0->current_length -
  				      (sizeof (*ip) + sizeof (*udp)));
  
    ip->length = clib_host_to_net_u16 (b0->current_length);
  
    ip->checksum = ip4_header_checksum (ip);
    udp->length = clib_host_to_net_u16 (b0->current_length - sizeof (*ip));
  
    if (frm->udp_checksum)
      {
        /* RFC 7011 section 10.3.2. */
        udp->checksum = ip4_tcp_udp_compute_checksum (vm, b0, ip);
        if (udp->checksum == 0)
  	udp->checksum = 0xffff;
      }
  
    ASSERT (ip4_header_checksum_is_valid (ip));
  
    /* Find or allocate a frame */
    f = fm->context[which].frames_per_worker[my_cpu_number];
    if (PREDICT_FALSE (f == 0))
      {
        u32 *to_next;
        f = vlib_get_frame_to_node (vm, ip4_lookup_node.index);
        fm->context[which].frames_per_worker[my_cpu_number] = f;
        u32 bi0 = vlib_get_buffer_index (vm, b0);
  
        /* Enqueue the buffer */
        to_next = vlib_frame_vector_args (f);
        to_next[0] = bi0;
        f->n_vectors = 1;
      }
  
    vlib_put_frame_to_node (vm, ip4_lookup_node.index, f);
    vlib_node_increment_counter (vm, flowprobe_l2_node.index,
  			       FLOWPROBE_ERROR_EXPORTED_PACKETS, 1);
  
    fm->context[which].frames_per_worker[my_cpu_number] = 0;
    fm->context[which].buffers_per_worker[my_cpu_number] = 0;
    fm->context[which].next_record_offset_per_worker[my_cpu_number] =
      flowprobe_get_headersize ();
  }
  
  static vlib_buffer_t *
  flowprobe_get_buffer (vlib_main_t * vm, flowprobe_variant_t which)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    flow_report_main_t *frm = &flow_report_main;
    vlib_buffer_t *b0;
    u32 bi0;
    u32 my_cpu_number = vm->thread_index;
  
    /* Find or allocate a buffer */
    b0 = fm->context[which].buffers_per_worker[my_cpu_number];
  
    /* Need to allocate a buffer? */
    if (PREDICT_FALSE (b0 == 0))
      {
        if (vlib_buffer_alloc (vm, &bi0, 1) != 1)
  	{
  	  vlib_node_increment_counter (vm, flowprobe_l2_node.index,
  				       FLOWPROBE_ERROR_BUFFER, 1);
  	  return 0;
  	}
  
        /* Initialize the buffer */
        b0 = fm->context[which].buffers_per_worker[my_cpu_number] =
  	vlib_get_buffer (vm, bi0);
        VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);
  
        b0->current_data = 0;
        b0->current_length = flowprobe_get_headersize ();
        b0->flags |=
  	(VLIB_BUFFER_TOTAL_LENGTH_VALID | VNET_BUFFER_F_FLOW_REPORT);
        vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;
        vnet_buffer (b0)->sw_if_index[VLIB_TX] = frm->fib_index;
        fm->context[which].next_record_offset_per_worker[my_cpu_number] =
  	b0->current_length;
      }
  
    return b0;
  }
  
  static void
  flowprobe_export_entry (vlib_main_t * vm, flowprobe_entry_t * e)
  {
    u32 my_cpu_number = vm->thread_index;
    flowprobe_main_t *fm = &flowprobe_main;
    flow_report_main_t *frm = &flow_report_main;
    vlib_buffer_t *b0;
    bool collect_ip4 = false, collect_ip6 = false;
    flowprobe_variant_t which = e->key.which;
    flowprobe_record_t flags = fm->context[which].flags;
    u16 offset =
      fm->context[which].next_record_offset_per_worker[my_cpu_number];
  
    if (offset < flowprobe_get_headersize ())
      offset = flowprobe_get_headersize ();
  
    b0 = flowprobe_get_buffer (vm, which);
    /* No available buffer, what to do... */
    if (b0 == 0)
      return;
  
    if (flags & FLOW_RECORD_L3)
      {
        collect_ip4 = which == FLOW_VARIANT_L2_IP4 || which == FLOW_VARIANT_IP4;
        collect_ip6 = which == FLOW_VARIANT_L2_IP6 || which == FLOW_VARIANT_IP6;
      }
  
    offset += flowprobe_common_add (b0, e, offset);
  
    if (flags & FLOW_RECORD_L2)
      offset += flowprobe_l2_add (b0, e, offset);
    if (collect_ip6)
      offset += flowprobe_l3_ip6_add (b0, e, offset);
    if (collect_ip4)
      offset += flowprobe_l3_ip4_add (b0, e, offset);
    if (flags & FLOW_RECORD_L4)
      offset += flowprobe_l4_add (b0, e, offset);
  
    /* Reset per flow-export counters */
    e->packetcount = 0;
    e->octetcount = 0;
    e->last_exported = vlib_time_now (vm);
  
    b0->current_length = offset;
  
    fm->context[which].next_record_offset_per_worker[my_cpu_number] = offset;
    /* Time to flush the buffer? */
    if (offset + fm->template_size[flags] > frm->path_mtu)
      flowprobe_export_send (vm, b0, which);
  }
  
  uword
  flowprobe_node_fn (vlib_main_t * vm,
  		   vlib_node_runtime_t * node, vlib_frame_t * frame,
  		   flowprobe_variant_t which)
  {
    u32 n_left_from, *from, *to_next;
    flowprobe_next_t next_index;
    flowprobe_main_t *fm = &flowprobe_main;
    timestamp_nsec_t timestamp;
  
    unix_time_now_nsec_fraction (&timestamp.sec, &timestamp.nsec);
  
    from = vlib_frame_vector_args (frame);
    n_left_from = frame->n_vectors;
    next_index = node->cached_next_index;
  
    while (n_left_from > 0)
      {
        u32 n_left_to_next;
  
        vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  
        while (n_left_from >= 4 && n_left_to_next >= 2)
  	{
  	  u32 next0 = FLOWPROBE_NEXT_DROP;
  	  u32 next1 = FLOWPROBE_NEXT_DROP;
  	  u16 len0, len1;
  	  u32 bi0, bi1;
  	  vlib_buffer_t *b0, *b1;
  
  	  /* Prefetch next iteration. */
  	  {
  	    vlib_buffer_t *p2, *p3;
  
  	    p2 = vlib_get_buffer (vm, from[2]);
  	    p3 = vlib_get_buffer (vm, from[3]);
  
  	    vlib_prefetch_buffer_header (p2, LOAD);
  	    vlib_prefetch_buffer_header (p3, LOAD);
  
  	    CLIB_PREFETCH (p2->data, CLIB_CACHE_LINE_BYTES, STORE);
  	    CLIB_PREFETCH (p3->data, CLIB_CACHE_LINE_BYTES, STORE);
  	  }
  
  	  /* speculatively enqueue b0 and b1 to the current next frame */
  	  to_next[0] = bi0 = from[0];
  	  to_next[1] = bi1 = from[1];
  	  from += 2;
  	  to_next += 2;
  	  n_left_from -= 2;
  	  n_left_to_next -= 2;
  
  	  b0 = vlib_get_buffer (vm, bi0);
  	  b1 = vlib_get_buffer (vm, bi1);
  
  	  vnet_feature_next (&next0, b0);
  	  vnet_feature_next (&next1, b1);
  
  	  len0 = vlib_buffer_length_in_chain (vm, b0);
  	  ethernet_header_t *eh0 = vlib_buffer_get_current (b0);
  	  u16 ethertype0 = clib_net_to_host_u16 (eh0->type);
  
  	  if (PREDICT_TRUE ((b0->flags & VNET_BUFFER_F_FLOW_REPORT) == 0))
  	    add_to_flow_record_state (vm, node, fm, b0, timestamp, len0,
  				      flowprobe_get_variant
  				      (which, fm->context[which].flags,
  				       ethertype0), 0);
  
  	  len1 = vlib_buffer_length_in_chain (vm, b1);
  	  ethernet_header_t *eh1 = vlib_buffer_get_current (b1);
  	  u16 ethertype1 = clib_net_to_host_u16 (eh1->type);
  
  	  if (PREDICT_TRUE ((b1->flags & VNET_BUFFER_F_FLOW_REPORT) == 0))
  	    add_to_flow_record_state (vm, node, fm, b1, timestamp, len1,
  				      flowprobe_get_variant
  				      (which, fm->context[which].flags,
  				       ethertype1), 0);
  
  	  /* verify speculative enqueues, maybe switch current next frame */
  	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
  					   to_next, n_left_to_next,
  					   bi0, bi1, next0, next1);
  	}
  
        while (n_left_from > 0 && n_left_to_next > 0)
  	{
  	  u32 bi0;
  	  vlib_buffer_t *b0;
  	  u32 next0 = FLOWPROBE_NEXT_DROP;
  	  u16 len0;
  
  	  /* speculatively enqueue b0 to the current next frame */
  	  bi0 = from[0];
  	  to_next[0] = bi0;
  	  from += 1;
  	  to_next += 1;
  	  n_left_from -= 1;
  	  n_left_to_next -= 1;
  
  	  b0 = vlib_get_buffer (vm, bi0);
  
  	  vnet_feature_next (&next0, b0);
  
  	  len0 = vlib_buffer_length_in_chain (vm, b0);
  	  ethernet_header_t *eh0 = vlib_buffer_get_current (b0);
  	  u16 ethertype0 = clib_net_to_host_u16 (eh0->type);
  
  	  if (PREDICT_TRUE ((b0->flags & VNET_BUFFER_F_FLOW_REPORT) == 0))
  	    {
  	      flowprobe_trace_t *t = 0;
  	      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
  				 && (b0->flags & VLIB_BUFFER_IS_TRACED)))
  		t = vlib_add_trace (vm, node, b0, sizeof (*t));
  
  	      add_to_flow_record_state (vm, node, fm, b0, timestamp, len0,
  					flowprobe_get_variant
  					(which, fm->context[which].flags,
  					 ethertype0), t);
  	    }
  
  	  /* verify speculative enqueue, maybe switch current next frame */
  	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
  					   to_next, n_left_to_next,
  					   bi0, next0);
  	}
  
        vlib_put_next_frame (vm, node, next_index, n_left_to_next);
      }
    return frame->n_vectors;
  }
  
  static uword
  flowprobe_ip4_node_fn (vlib_main_t * vm,
  		       vlib_node_runtime_t * node, vlib_frame_t * frame)
  {
    return flowprobe_node_fn (vm, node, frame, FLOW_VARIANT_IP4);
  }
  
  static uword
  flowprobe_ip6_node_fn (vlib_main_t * vm,
  		       vlib_node_runtime_t * node, vlib_frame_t * frame)
  {
    return flowprobe_node_fn (vm, node, frame, FLOW_VARIANT_IP6);
  }
  
  static uword
  flowprobe_l2_node_fn (vlib_main_t * vm,
  		      vlib_node_runtime_t * node, vlib_frame_t * frame)
  {
    return flowprobe_node_fn (vm, node, frame, FLOW_VARIANT_L2);
  }
  
  static inline void
  flush_record (flowprobe_variant_t which)
  {
    vlib_main_t *vm = vlib_get_main ();
    vlib_buffer_t *b = flowprobe_get_buffer (vm, which);
    if (b)
      flowprobe_export_send (vm, b, which);
  }
  
  void
  flowprobe_flush_callback_ip4 (void)
  {
    flush_record (FLOW_VARIANT_IP4);
  }
  
  void
  flowprobe_flush_callback_ip6 (void)
  {
    flush_record (FLOW_VARIANT_IP6);
  }
  
  void
  flowprobe_flush_callback_l2 (void)
  {
    flush_record (FLOW_VARIANT_L2);
    flush_record (FLOW_VARIANT_L2_IP4);
    flush_record (FLOW_VARIANT_L2_IP6);
  }
  
  
  static void
  flowprobe_delete_by_index (u32 my_cpu_number, u32 poolindex)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    flowprobe_entry_t *e;
    u32 h;
  
    e = pool_elt_at_index (fm->pool_per_worker[my_cpu_number], poolindex);
  
    /* Get my index */
    h = flowprobe_hash (&e->key);
  
    /* Reset hash */
    fm->hash_per_worker[my_cpu_number][h] = ~0;
  
    pool_put_index (fm->pool_per_worker[my_cpu_number], poolindex);
  }
  
  
  /* Per worker process processing the active/passive expired entries */
  static uword
  flowprobe_walker_process (vlib_main_t * vm,
  			  vlib_node_runtime_t * rt, vlib_frame_t * f)
  {
    flowprobe_main_t *fm = &flowprobe_main;
    flow_report_main_t *frm = &flow_report_main;
    flowprobe_entry_t *e;
  
    /*
     * $$$$ Remove this check from here and track FRM status and disable
     * this process if required.
     */
    if (frm->ipfix_collector.as_u32 == 0 || frm->src_address.as_u32 == 0)
      {
        fm->disabled = true;
        return 0;
      }
    fm->disabled = false;
  
    u32 cpu_index = os_get_thread_index ();
    u32 *to_be_removed = 0, *i;
  
    /*
     * Tick the timer when required and process the vector of expired
     * timers
     */
    f64 start_time = vlib_time_now (vm);
    u32 count = 0;
  
    tw_timer_expire_timers_2t_1w_2048sl (fm->timers_per_worker[cpu_index],
  				       start_time);
  
    vec_foreach (i, fm->expired_passive_per_worker[cpu_index])
    {
      u32 exported = 0;
      f64 now = vlib_time_now (vm);
      if (now > start_time + 100e-6
  	|| exported > FLOW_MAXIMUM_EXPORT_ENTRIES - 1)
        break;
  
      if (pool_is_free_index (fm->pool_per_worker[cpu_index], *i))
        {
  	clib_warning ("Element is %d is freed already\n", *i);
  	continue;
        }
      else
        e = pool_elt_at_index (fm->pool_per_worker[cpu_index], *i);
  
      /* Check last update timestamp. If it is longer than passive time nuke
       * entry. Otherwise restart timer with what's left
       * Premature passive timer by more than 10%
       */
      if ((now - e->last_updated) < (u64) (fm->passive_timer * 0.9))
        {
  	u64 delta = fm->passive_timer - (now - e->last_updated);
  	e->passive_timer_handle = tw_timer_start_2t_1w_2048sl
  	  (fm->timers_per_worker[cpu_index], *i, 0, delta);
        }
      else			/* Nuke entry */
        {
  	vec_add1 (to_be_removed, *i);
        }
      /* If anything to report send it to the exporter */
      if (e->packetcount && now > e->last_exported + fm->active_timer)
        {
  	exported++;
  	flowprobe_export_entry (vm, e);
        }
      count++;
    }
    if (count)
      vec_delete (fm->expired_passive_per_worker[cpu_index], count, 0);
  
    vec_foreach (i, to_be_removed) flowprobe_delete_by_index (cpu_index, *i);
    vec_free (to_be_removed);
  
    return 0;
  }
  
  /* *INDENT-OFF* */
  VLIB_REGISTER_NODE (flowprobe_ip4_node) = {
    .function = flowprobe_ip4_node_fn,
    .name = "flowprobe-ip4",
    .vector_size = sizeof (u32),
    .format_trace = format_flowprobe_trace,
    .type = VLIB_NODE_TYPE_INTERNAL,
    .n_errors = ARRAY_LEN(flowprobe_error_strings),
    .error_strings = flowprobe_error_strings,
    .n_next_nodes = FLOWPROBE_N_NEXT,
    .next_nodes = FLOWPROBE_NEXT_NODES,
  };
  VLIB_REGISTER_NODE (flowprobe_ip6_node) = {
    .function = flowprobe_ip6_node_fn,
    .name = "flowprobe-ip6",
    .vector_size = sizeof (u32),
    .format_trace = format_flowprobe_trace,
    .type = VLIB_NODE_TYPE_INTERNAL,
    .n_errors = ARRAY_LEN(flowprobe_error_strings),
    .error_strings = flowprobe_error_strings,
    .n_next_nodes = FLOWPROBE_N_NEXT,
    .next_nodes = FLOWPROBE_NEXT_NODES,
  };
  VLIB_REGISTER_NODE (flowprobe_l2_node) = {
    .function = flowprobe_l2_node_fn,
    .name = "flowprobe-l2",
    .vector_size = sizeof (u32),
    .format_trace = format_flowprobe_trace,
    .type = VLIB_NODE_TYPE_INTERNAL,
    .n_errors = ARRAY_LEN(flowprobe_error_strings),
    .error_strings = flowprobe_error_strings,
    .n_next_nodes = FLOWPROBE_N_NEXT,
    .next_nodes = FLOWPROBE_NEXT_NODES,
  };
  VLIB_REGISTER_NODE (flowprobe_walker_node) = {
    .function = flowprobe_walker_process,
    .name = "flowprobe-walker",
    .type = VLIB_NODE_TYPE_INPUT,
    .state = VLIB_NODE_STATE_INTERRUPT,
  };
  /* *INDENT-ON* */
  
  /*
   * fd.io coding-style-patch-verification: ON
   *
   * Local Variables:
   * eval: (c-set-style "gnu")
   * End:
   */
  