encap.c

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/*
 * Copyright (c) 2017 SUSE LLC.
 * 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 <vppinfra/error.h>
#include <vppinfra/hash.h>
#include <vnet/vnet.h>
#include <vnet/ip/ip.h>
#include <vnet/ethernet/ethernet.h>
#include <vnet/geneve/geneve.h>

/* Statistics (not all errors) */
#define foreach_geneve_encap_error    \
_(ENCAPSULATED, "good packets encapsulated")

static char *geneve_encap_error_strings[] = {
#define _(sym,string) string,
  foreach_geneve_encap_error
#undef _
};

typedef enum
{
#define _(sym,str) GENEVE_ENCAP_ERROR_##sym,
  foreach_geneve_encap_error
#undef _
    GENEVE_ENCAP_N_ERROR,
} geneve_encap_error_t;

typedef enum
{
  GENEVE_ENCAP_NEXT_DROP,
  GENEVE_ENCAP_N_NEXT,
} geneve_encap_next_t;

typedef struct
{
  u32 tunnel_index;
  u32 vni;
} geneve_encap_trace_t;

u8 *
format_geneve_encap_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 *);
  geneve_encap_trace_t *t = va_arg (*args, geneve_encap_trace_t *);

  s = format (s, "GENEVE encap to geneve_tunnel%d vni %d",
              t->tunnel_index, t->vni);
  return s;
}


#define foreach_fixed_header4_offset            \
    _(0) _(1) _(2) _(3)

#define foreach_fixed_header6_offset            \
    _(0) _(1) _(2) _(3) _(4) _(5) _(6)

always_inline uword
geneve_encap_inline (vlib_main_t * vm,
                     vlib_node_runtime_t * node,
                     vlib_frame_t * from_frame, u32 is_ip4)
{
  u32 n_left_from, next_index, *from, *to_next;
  geneve_main_t *vxm = &geneve_main;
  vnet_main_t *vnm = vxm->vnet_main;
  vnet_interface_main_t *im = &vnm->interface_main;
  u32 pkts_encapsulated = 0;
  u16 old_l0 = 0, old_l1 = 0;
  u32 thread_index = vlib_get_thread_index ();
  u32 stats_sw_if_index, stats_n_packets, stats_n_bytes;
  u32 sw_if_index0 = 0, sw_if_index1 = 0;
  u32 next0 = 0, next1 = 0;
  vnet_hw_interface_t *hi0, *hi1;
  geneve_tunnel_t *t0 = NULL, *t1 = NULL;

  from = vlib_frame_vector_args (from_frame);
  n_left_from = from_frame->n_vectors;

  next_index = node->cached_next_index;
  stats_sw_if_index = node->runtime_data[0];
  stats_n_packets = stats_n_bytes = 0;

  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 bi0, bi1;
          vlib_buffer_t *b0, *b1;
          u32 flow_hash0, flow_hash1;
          u32 len0, len1;
          ip4_header_t *ip4_0, *ip4_1;
          ip6_header_t *ip6_0, *ip6_1;
          udp_header_t *udp0, *udp1;
          u64 *copy_src0, *copy_dst0;
          u64 *copy_src1, *copy_dst1;
          u32 *copy_src_last0, *copy_dst_last0;
          u32 *copy_src_last1, *copy_dst_last1;
          u16 new_l0, new_l1;
          ip_csum_t sum0, sum1;

          /* 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, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
            CLIB_PREFETCH (p3->data, 2 * CLIB_CACHE_LINE_BYTES, LOAD);
          }

          bi0 = from[0];
          bi1 = from[1];
          to_next[0] = bi0;
          to_next[1] = bi1;
          from += 2;
          to_next += 2;
          n_left_to_next -= 2;
          n_left_from -= 2;

          b0 = vlib_get_buffer (vm, bi0);
          b1 = vlib_get_buffer (vm, bi1);

          flow_hash0 = vnet_l2_compute_flow_hash (b0);
          flow_hash1 = vnet_l2_compute_flow_hash (b1);

          /* Get next node index and adj index from tunnel next_dpo */
          if (sw_if_index0 != vnet_buffer (b0)->sw_if_index[VLIB_TX])
            {
              sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
              hi0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
              t0 = &vxm->tunnels[hi0->dev_instance];
              /* Note: change to always set next0 if it may be set to drop */
              next0 = t0->next_dpo.dpoi_next_node;
            }

          ASSERT (t0 != NULL);

          vnet_buffer (b0)->ip.adj_index[VLIB_TX] = t0->next_dpo.dpoi_index;

          /* Get next node index and adj index from tunnel next_dpo */
          if (sw_if_index1 != vnet_buffer (b1)->sw_if_index[VLIB_TX])
            {
              sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_TX];
              hi1 = vnet_get_sup_hw_interface (vnm, sw_if_index1);
              t1 = &vxm->tunnels[hi1->dev_instance];
              /* Note: change to always set next1 if it may be set to drop */
              next1 = t1->next_dpo.dpoi_next_node;
            }

          ASSERT (t1 != NULL);

          vnet_buffer (b1)->ip.adj_index[VLIB_TX] = t1->next_dpo.dpoi_index;

          /* Apply the rewrite string. $$$$ vnet_rewrite? */
          vlib_buffer_advance (b0, -(word) _vec_len (t0->rewrite));
          vlib_buffer_advance (b1, -(word) _vec_len (t1->rewrite));

          if (is_ip4)
            {
              u8 ip4_geneve_base_header_len =
                sizeof (ip4_header_t) + sizeof (udp_header_t) +
                GENEVE_BASE_HEADER_LENGTH;
              u8 ip4_geneve_header_total_len0 = ip4_geneve_base_header_len;
              u8 ip4_geneve_header_total_len1 = ip4_geneve_base_header_len;
#if SUPPORT_OPTIONS_HEADER==1
              ip4_geneve_header_total_len0 += t0->options_len;
              ip4_geneve_header_total_len1 += t1->options_len;
#endif
              ASSERT (vec_len (t0->rewrite) == ip4_geneve_header_total_len0);
              ASSERT (vec_len (t1->rewrite) == ip4_geneve_header_total_len1);

              ip4_0 = vlib_buffer_get_current (b0);
              ip4_1 = vlib_buffer_get_current (b1);

              /* Copy the fixed header */
              copy_dst0 = (u64 *) ip4_0;
              copy_src0 = (u64 *) t0->rewrite;
              copy_dst1 = (u64 *) ip4_1;
              copy_src1 = (u64 *) t1->rewrite;
              /* Copy first 32 octets 8-bytes at a time */
#define _(offs) copy_dst0[offs] = copy_src0[offs];
              foreach_fixed_header4_offset;
#undef _
#define _(offs) copy_dst1[offs] = copy_src1[offs];
              foreach_fixed_header4_offset;
#undef _
              /* Last 4 octets. Hopefully gcc will be our friend */
              copy_dst_last0 = (u32 *) (&copy_dst0[4]);
              copy_src_last0 = (u32 *) (&copy_src0[4]);
              copy_dst_last0[0] = copy_src_last0[0];
              copy_dst_last1 = (u32 *) (&copy_dst1[4]);
              copy_src_last1 = (u32 *) (&copy_src1[4]);
              copy_dst_last1[0] = copy_src_last1[0];

              /* Fix the IP4 checksum and length */
              sum0 = ip4_0->checksum;
              new_l0 =          /* old_l0 always 0, see the rewrite setup */
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
              sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
                                     length /* changed member */ );
              ip4_0->checksum = ip_csum_fold (sum0);
              ip4_0->length = new_l0;
              sum1 = ip4_1->checksum;
              new_l1 =          /* old_l1 always 0, see the rewrite setup */
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1));
              sum1 = ip_csum_update (sum1, old_l1, new_l1, ip4_header_t,
                                     length /* changed member */ );
              ip4_1->checksum = ip_csum_fold (sum1);
              ip4_1->length = new_l1;

              /* Fix UDP length and set source port */
              udp0 = (udp_header_t *) (ip4_0 + 1);
              new_l0 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
                                      sizeof (*ip4_0));
              udp0->length = new_l0;
              udp0->src_port = flow_hash0;
              udp1 = (udp_header_t *) (ip4_1 + 1);
              new_l1 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1) -
                                      sizeof (*ip4_1));
              udp1->length = new_l1;
              udp1->src_port = flow_hash1;
            }
          else                  /* ipv6 */
            {
              int bogus = 0;

              u8 ip6_geneve_base_header_len =
                sizeof (ip6_header_t) + sizeof (udp_header_t) +
                GENEVE_BASE_HEADER_LENGTH;
              u8 ip6_geneve_header_total_len0 = ip6_geneve_base_header_len;
              u8 ip6_geneve_header_total_len1 = ip6_geneve_base_header_len;
#if SUPPORT_OPTIONS_HEADER==1
              ip6_geneve_header_total_len0 += t0->options_len;
              ip6_geneve_header_total_len1 += t1->options_len;
#endif
              ASSERT (vec_len (t0->rewrite) == ip6_geneve_header_total_len0);
              ASSERT (vec_len (t1->rewrite) == ip6_geneve_header_total_len1);

              ip6_0 = vlib_buffer_get_current (b0);
              ip6_1 = vlib_buffer_get_current (b1);

              /* Copy the fixed header */
              copy_dst0 = (u64 *) ip6_0;
              copy_src0 = (u64 *) t0->rewrite;
              copy_dst1 = (u64 *) ip6_1;
              copy_src1 = (u64 *) t1->rewrite;
              /* Copy first 56 (ip6) octets 8-bytes at a time */
#define _(offs) copy_dst0[offs] = copy_src0[offs];
              foreach_fixed_header6_offset;
#undef _
#define _(offs) copy_dst1[offs] = copy_src1[offs];
              foreach_fixed_header6_offset;
#undef _
              /* Fix IP6 payload length */
              new_l0 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
                                      - sizeof (*ip6_0));
              ip6_0->payload_length = new_l0;
              new_l1 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b1)
                                      - sizeof (*ip6_1));
              ip6_1->payload_length = new_l1;

              /* Fix UDP length  and set source port */
              udp0 = (udp_header_t *) (ip6_0 + 1);
              udp0->length = new_l0;
              udp0->src_port = flow_hash0;
              udp1 = (udp_header_t *) (ip6_1 + 1);
              udp1->length = new_l1;
              udp1->src_port = flow_hash1;

              /* IPv6 UDP checksum is mandatory */
              udp0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0,
                                                                  ip6_0,
                                                                  &bogus);
              ASSERT (bogus == 0);
              if (udp0->checksum == 0)
                udp0->checksum = 0xffff;
              udp1->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b1,
                                                                  ip6_1,
                                                                  &bogus);
              ASSERT (bogus == 0);
              if (udp1->checksum == 0)
                udp1->checksum = 0xffff;
            }

          pkts_encapsulated += 2;
          len0 = vlib_buffer_length_in_chain (vm, b0);
          len1 = vlib_buffer_length_in_chain (vm, b1);
          stats_n_packets += 2;
          stats_n_bytes += len0 + len1;

          /* Batch stats increment on the same geneve tunnel so counter is not
             incremented per packet. Note stats are still incremented for deleted
             and admin-down tunnel where packets are dropped. It is not worthwhile
             to check for this rare case and affect normal path performance. */
          if (PREDICT_FALSE ((sw_if_index0 != stats_sw_if_index) ||
                             (sw_if_index1 != stats_sw_if_index)))
            {
              stats_n_packets -= 2;
              stats_n_bytes -= len0 + len1;
              if (sw_if_index0 == sw_if_index1)
                {
                  if (stats_n_packets)
                    vlib_increment_combined_counter
                      (im->combined_sw_if_counters +
                       VNET_INTERFACE_COUNTER_TX, thread_index,
                       stats_sw_if_index, stats_n_packets, stats_n_bytes);
                  stats_sw_if_index = sw_if_index0;
                  stats_n_packets = 2;
                  stats_n_bytes = len0 + len1;
                }
              else
                {
                  vlib_increment_combined_counter
                    (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
                     thread_index, sw_if_index0, 1, len0);
                  vlib_increment_combined_counter
                    (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
                     thread_index, sw_if_index1, 1, len1);
                }
            }

          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
            {
              geneve_encap_trace_t *tr =
                vlib_add_trace (vm, node, b0, sizeof (*tr));
              tr->tunnel_index = t0 - vxm->tunnels;
              tr->vni = t0->vni;
            }

          if (PREDICT_FALSE (b1->flags & VLIB_BUFFER_IS_TRACED))
            {
              geneve_encap_trace_t *tr =
                vlib_add_trace (vm, node, b1, sizeof (*tr));
              tr->tunnel_index = t1 - vxm->tunnels;
              tr->vni = t1->vni;
            }

          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 flow_hash0;
          u32 len0;
          ip4_header_t *ip4_0;
          ip6_header_t *ip6_0;
          udp_header_t *udp0;
          u64 *copy_src0, *copy_dst0;
          u32 *copy_src_last0, *copy_dst_last0;
          u16 new_l0;
          ip_csum_t sum0;

          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);

          flow_hash0 = vnet_l2_compute_flow_hash (b0);

          /* Get next node index and adj index from tunnel next_dpo */
          if (sw_if_index0 != vnet_buffer (b0)->sw_if_index[VLIB_TX])
            {
              sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_TX];
              hi0 = vnet_get_sup_hw_interface (vnm, sw_if_index0);
              t0 = &vxm->tunnels[hi0->dev_instance];
              /* Note: change to always set next0 if it may be set to drop */
              next0 = t0->next_dpo.dpoi_next_node;
            }
          vnet_buffer (b0)->ip.adj_index[VLIB_TX] = t0->next_dpo.dpoi_index;

          /* Apply the rewrite string. $$$$ vnet_rewrite? */
          vlib_buffer_advance (b0, -(word) _vec_len (t0->rewrite));

          if (is_ip4)
            {
              u8 ip4_geneve_base_header_len =
                sizeof (ip4_header_t) + sizeof (udp_header_t) +
                GENEVE_BASE_HEADER_LENGTH;
              u8 ip4_geneve_header_total_len0 = ip4_geneve_base_header_len;
#if SUPPORT_OPTIONS_HEADER==1
              ip4_geneve_header_total_len0 += t0->options_len;
#endif
              ASSERT (vec_len (t0->rewrite) == ip4_geneve_header_total_len0);

              ip4_0 = vlib_buffer_get_current (b0);

              /* Copy the fixed header */
              copy_dst0 = (u64 *) ip4_0;
              copy_src0 = (u64 *) t0->rewrite;
              /* Copy first 32 octets 8-bytes at a time */
#define _(offs) copy_dst0[offs] = copy_src0[offs];
              foreach_fixed_header4_offset;
#undef _
              /* Last 4 octets. Hopefully gcc will be our friend */
              copy_dst_last0 = (u32 *) (&copy_dst0[4]);
              copy_src_last0 = (u32 *) (&copy_src0[4]);
              copy_dst_last0[0] = copy_src_last0[0];

              /* Fix the IP4 checksum and length */
              sum0 = ip4_0->checksum;
              new_l0 =          /* old_l0 always 0, see the rewrite setup */
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
              sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
                                     length /* changed member */ );
              ip4_0->checksum = ip_csum_fold (sum0);
              ip4_0->length = new_l0;

              /* Fix UDP length and set source port */
              udp0 = (udp_header_t *) (ip4_0 + 1);
              new_l0 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
                                      sizeof (*ip4_0));
              udp0->length = new_l0;
              udp0->src_port = flow_hash0;
            }

          else                  /* ip6 path */
            {
              int bogus = 0;

              u8 ip6_geneve_base_header_len =
                sizeof (ip6_header_t) + sizeof (udp_header_t) +
                GENEVE_BASE_HEADER_LENGTH;
              u8 ip6_geneve_header_total_len0 = ip6_geneve_base_header_len;
#if SUPPORT_OPTIONS_HEADER==1
              ip6_geneve_header_total_len0 += t0->options_len;
#endif
              ASSERT (vec_len (t0->rewrite) == ip6_geneve_header_total_len0);

              ip6_0 = vlib_buffer_get_current (b0);
              /* Copy the fixed header */
              copy_dst0 = (u64 *) ip6_0;
              copy_src0 = (u64 *) t0->rewrite;
              /* Copy first 56 (ip6) octets 8-bytes at a time */
#define _(offs) copy_dst0[offs] = copy_src0[offs];
              foreach_fixed_header6_offset;
#undef _
              /* Fix IP6 payload length */
              new_l0 =
                clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0)
                                      - sizeof (*ip6_0));
              ip6_0->payload_length = new_l0;

              /* Fix UDP length  and set source port */
              udp0 = (udp_header_t *) (ip6_0 + 1);
              udp0->length = new_l0;
              udp0->src_port = flow_hash0;

              /* IPv6 UDP checksum is mandatory */
              udp0->checksum = ip6_tcp_udp_icmp_compute_checksum (vm, b0,
                                                                  ip6_0,
                                                                  &bogus);
              ASSERT (bogus == 0);
              if (udp0->checksum == 0)
                udp0->checksum = 0xffff;
            }

          pkts_encapsulated++;
          len0 = vlib_buffer_length_in_chain (vm, b0);
          stats_n_packets += 1;
          stats_n_bytes += len0;

          /* Batch stats increment on the same geneve tunnel so counter is not
             incremented per packet. Note stats are still incremented for deleted
             and admin-down tunnel where packets are dropped. It is not worthwhile
             to check for this rare case and affect normal path performance. */
          if (PREDICT_FALSE (sw_if_index0 != stats_sw_if_index))
            {
              stats_n_packets -= 1;
              stats_n_bytes -= len0;
              if (stats_n_packets)
                vlib_increment_combined_counter
                  (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
                   thread_index, stats_sw_if_index,
                   stats_n_packets, stats_n_bytes);
              stats_n_packets = 1;
              stats_n_bytes = len0;
              stats_sw_if_index = sw_if_index0;
            }

          if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
            {
              geneve_encap_trace_t *tr =
                vlib_add_trace (vm, node, b0, sizeof (*tr));
              tr->tunnel_index = t0 - vxm->tunnels;
              tr->vni = t0->vni;
            }
          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);
    }

  /* Do we still need this now that tunnel tx stats is kept? */
  vlib_node_increment_counter (vm, node->node_index,
                               GENEVE_ENCAP_ERROR_ENCAPSULATED,
                               pkts_encapsulated);

  /* Increment any remaining batch stats */
  if (stats_n_packets)
    {
      vlib_increment_combined_counter
        (im->combined_sw_if_counters + VNET_INTERFACE_COUNTER_TX,
         thread_index, stats_sw_if_index, stats_n_packets, stats_n_bytes);
      node->runtime_data[0] = stats_sw_if_index;
    }

  return from_frame->n_vectors;
}

static uword
geneve4_encap (vlib_main_t * vm,
               vlib_node_runtime_t * node, vlib_frame_t * from_frame)
{
  return geneve_encap_inline (vm, node, from_frame, /* is_ip4 */ 1);
}

static uword
geneve6_encap (vlib_main_t * vm,
               vlib_node_runtime_t * node, vlib_frame_t * from_frame)
{
  return geneve_encap_inline (vm, node, from_frame, /* is_ip4 */ 0);
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (geneve4_encap_node) = {
  .function = geneve4_encap,
  .name = "geneve4-encap",
  .vector_size = sizeof (u32),
  .format_trace = format_geneve_encap_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (geneve_encap_error_strings),
  .error_strings = geneve_encap_error_strings,
  .n_next_nodes = GENEVE_ENCAP_N_NEXT,
  .next_nodes = {
        [GENEVE_ENCAP_NEXT_DROP] = "error-drop",
  },
};

VLIB_NODE_FUNCTION_MULTIARCH (geneve4_encap_node, geneve4_encap)

VLIB_REGISTER_NODE (geneve6_encap_node) = {
  .function = geneve6_encap,
  .name = "geneve6-encap",
  .vector_size = sizeof (u32),
  .format_trace = format_geneve_encap_trace,
  .type = VLIB_NODE_TYPE_INTERNAL,
  .n_errors = ARRAY_LEN (geneve_encap_error_strings),
  .error_strings = geneve_encap_error_strings,
  .n_next_nodes = GENEVE_ENCAP_N_NEXT,
  .next_nodes = {
        [GENEVE_ENCAP_NEXT_DROP] = "error-drop",
  },
};

VLIB_NODE_FUNCTION_MULTIARCH (geneve6_encap_node, geneve6_encap)
/* *INDENT-ON* */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */