input.c

Go to the documentation of this file.

/*
 *------------------------------------------------------------------
 * 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/plugin/plugin.h>
#include <vpp/app/version.h>
#include <vnet/ip/ip.h>
#include <vlib/unix/unix.h>
#include <vnet/adj/adj_mcast.h>

#include <igmp/igmp.h>
#include <igmp/error.h>

#include <limits.h>

/* TODO: mld...
typedef enum
{
  MLD_INPUT_NEXT_DROP,
  ...
} mld_input_next_t;
*/

typedef enum
{
  IGMP_INPUT_NEXT_DROP,
  IGMP_INPUT_NEXT_PARSE_QUERY,
  IGMP_INPUT_NEXT_PARSE_REPORT,
  IGMP_INPUT_N_NEXT,
} igmp_input_next_t;

typedef enum
{
  IGMP_PARSE_QUERY_NEXT_DROP,
  IGMP_PARSE_QUERY_N_NEXT,
} igmp_parse_query_next_t;

typedef enum
{
  IGMP_PARSE_REPORT_NEXT_DROP,
  IGMP_PARSE_REPORT_N_NEXT,
} igmp_parse_report_next_t;

char *igmp_error_strings[] = {
#define _(sym,string) string,
  foreach_igmp_error
#undef _
};

typedef struct
{
  u32 next_index;
  u32 sw_if_index;

  u8 packet_data[64];
} igmp_input_trace_t;

static u8 *
format_igmp_input_trace (u8 * s, va_list * va)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
  igmp_input_trace_t *t = va_arg (*va, igmp_input_trace_t *);

  s =
    format (s, "sw_if_index %u next-index %u", t->sw_if_index, t->next_index);
  s =
    format (s, "\n%U", format_igmp_header, t->packet_data,
            sizeof (t->packet_data));
  return s;
}

static u8 *
format_igmp_parse_report_trace (u8 * s, va_list * va)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
  igmp_input_trace_t *t = va_arg (*va, igmp_input_trace_t *);

  s =
    format (s, "sw_if_index %u next-index %u", t->sw_if_index, t->next_index);
  s =
    format (s, "\n%U", format_igmp_report_v3, t->packet_data,
            sizeof (t->packet_data));
  return s;
}

static u8 *
format_igmp_parse_query_trace (u8 * s, va_list * va)
{
  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
  CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
  igmp_input_trace_t *t = va_arg (*va, igmp_input_trace_t *);

  s =
    format (s, "sw_if_index %u next-input %u", t->sw_if_index, t->next_index);
  s =
    format (s, "\n%U", format_igmp_query_v3, t->packet_data,
            sizeof (t->packet_data));
  return s;
}

uword
igmp_input (vlib_main_t * vm, vlib_node_runtime_t * node,
            vlib_frame_t * frame)
{
  DBG ("IGMP_INPUT");
  u32 n_left_from, *from, *to_next;
  igmp_parse_query_next_t next_index;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, igmp_input_node.index);
  u8 error;
  ip_csum_t sum;
  u16 csum;

  error = IGMP_ERROR_NONE;

  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 > 0 && n_left_to_next > 0)
        {
          vlib_buffer_t *b;
          ip4_header_t *ip;
          u32 bi, next;
          next = IGMP_INPUT_NEXT_DROP;

          bi = from[0];
          to_next[0] = bi;
          from++;
          to_next++;
          n_left_from--;
          n_left_to_next--;

          b = vlib_get_buffer (vm, bi);
          ip = vlib_buffer_get_current (b);

          if (ip->protocol != 2)
            {
              error = IGMP_ERROR_INVALID_PROTOCOL;
              next = IGMP_INPUT_NEXT_DROP;
              goto next_buffer;
            }

          vlib_buffer_advance (b, ip4_header_bytes (ip));

          igmp_header_t *igmp = vlib_buffer_get_current (b);

          u16 checksum = igmp->checksum;
          igmp->checksum = 0;
          sum = ip_incremental_checksum (0, igmp,
                                         clib_net_to_host_u16 (ip->length) -
                                         ip4_header_bytes (ip));
          igmp->checksum = checksum;
          csum = ~ip_csum_fold (sum);
          if (checksum != csum)
            {
              error = IGMP_ERROR_BAD_CHECKSUM;
              next = IGMP_INPUT_NEXT_DROP;
              goto next_buffer;
            }

          /* TODO: IGMPv2 and IGMPv1 */
          switch (igmp->type)
            {
            case IGMP_TYPE_membership_query:
              next = IGMP_INPUT_NEXT_PARSE_QUERY;
              break;
            case IGMP_TYPE_membership_report_v3:
              next = IGMP_INPUT_NEXT_PARSE_REPORT;
              break;
            default:
              error = IGMP_ERROR_UNKNOWN_TYPE;
              next = IGMP_INPUT_NEXT_DROP;
              break;
            }
        next_buffer:
          b->error = error_node->errors[error];

          if (node->flags & VLIB_NODE_FLAG_TRACE)
            {
              igmp_input_trace_t *tr;
              tr = vlib_add_trace (vm, node, b, sizeof (*tr));
              tr->next_index = next;
              tr->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
              clib_memcpy (tr->packet_data, vlib_buffer_get_current (b),
                           sizeof (tr->packet_data));
            }

          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
                                           n_left_to_next, bi, next);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  return frame->n_vectors;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (igmp_input_node) =
{
  .function = igmp_input,
  .name = "igmp-input",
  .vector_size = sizeof (u32),

  .format_buffer = format_igmp_header,
  .format_trace = format_igmp_input_trace,

  .n_errors = IGMP_N_ERROR,
  .error_strings = igmp_error_strings,

  .n_next_nodes = IGMP_INPUT_N_NEXT,
  .next_nodes = {
      [IGMP_INPUT_NEXT_DROP] = "error-drop",
      [IGMP_INPUT_NEXT_PARSE_QUERY] = "igmp-parse-query",
      [IGMP_INPUT_NEXT_PARSE_REPORT] = "igmp-parse-report",
  }
};
/* *INDENT-ON* */

uword
igmp_parse_query (vlib_main_t * vm, vlib_node_runtime_t * node,
                  vlib_frame_t * frame)
{
  DBG ("IGMP_PARSE_QUERY");

  u32 n_left_from, *from, *to_next;
  igmp_parse_query_next_t next_index;
  igmp_main_t *im = &igmp_main;
  igmp_config_t *config;

  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 > 0 && n_left_to_next > 0)
        {
          vlib_buffer_t *b;
          u32 sw_if_index, bi, next;
          next = IGMP_PARSE_QUERY_NEXT_DROP;

          bi = from[0];
          to_next[0] = bi;
          from++;
          to_next++;
          n_left_from--;
          n_left_to_next--;

          b = vlib_get_buffer (vm, bi);
          sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];

          igmp_membership_query_v3_t *igmp = vlib_buffer_get_current (b);
          ASSERT (igmp->header.type == IGMP_TYPE_membership_query);

          /* if group address is zero, this is a general query */
          if (igmp->dst.as_u32 == 0)
            {
              config = igmp_config_lookup (im, sw_if_index);
              if (!config)
                {
                  DBG ("No config on interface %u", sw_if_index);
                }
              else
                {
                  /* WIP
                   *
                   * TODO: divide to multipe reports in random time range [now, max resp time]
                   */
                  u32 seed = vlib_time_now (vm);
                  f64 next_resp_time = random_f64 (&seed) *
                    (f64) (igmp->header.code / 10) + vlib_time_now (vm);
                  config->flags |= IGMP_CONFIG_FLAG_CAN_SEND_REPORT;
                  igmp_create_int_timer (next_resp_time, sw_if_index,
                                         igmp_send_report);
                  vlib_process_signal_event (vm,
                                             igmp_timer_process_node.index,
                                             IGMP_PROCESS_EVENT_UPDATE_TIMER,
                                             0);
                }
            }

          if (node->flags & VLIB_NODE_FLAG_TRACE)
            {
              igmp_input_trace_t *tr;
              tr = vlib_add_trace (vm, node, b, sizeof (*tr));
              tr->next_index = next;
              tr->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
              clib_memcpy (tr->packet_data, vlib_buffer_get_current (b),
                           sizeof (tr->packet_data));
            }
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
                                           n_left_to_next, bi, next);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  return frame->n_vectors;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (igmp_parse_query_node) =
{
  .function = igmp_parse_query,
  .name = "igmp-parse-query",
  .vector_size = sizeof (u32),

  .format_buffer = format_igmp_query_v3,
  .format_trace = format_igmp_parse_query_trace,

  .n_errors = IGMP_N_ERROR,
  .error_strings = igmp_error_strings,

  .n_next_nodes = IGMP_PARSE_QUERY_N_NEXT,
  .next_nodes = {
    [IGMP_PARSE_QUERY_NEXT_DROP] = "error-drop",
  }
};
/* *INDENT-ON* */

uword
igmp_parse_report (vlib_main_t * vm, vlib_node_runtime_t * node,
                   vlib_frame_t * frame)
{
  DBG ("IGMP_PARSE_REPORT");

  igmp_main_t *im = &igmp_main;
  u32 n_left_from, *from, *to_next;
  igmp_input_next_t next_index;
  igmp_config_t *config;
  igmp_sg_t *sg;
  igmp_membership_group_v3_t *group;
  ip4_address_t *src;
  igmp_sg_key_t key;
  memset (&key, 0, sizeof (igmp_sg_key_t));
  ip46_address_t saddr;
  memset (&saddr, 0, sizeof (ip46_address_t));
  ip46_address_t gaddr;
  memset (&gaddr, 0, sizeof (ip46_address_t));
  u32 len;
  vlib_node_runtime_t *error_node =
    vlib_node_get_runtime (vm, igmp_input_node.index);
  u8 error;

  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 > 0 && n_left_to_next > 0)
        {
          vlib_buffer_t *b;
          u32 sw_if_index, bi, next;
          next = IGMP_PARSE_REPORT_NEXT_DROP;

          bi = from[0];
          to_next[0] = bi;
          from++;
          to_next++;
          n_left_from--;
          n_left_to_next--;

          b = vlib_get_buffer (vm, bi);

          error = IGMP_ERROR_NONE;
          b->error = error_node->errors[error];

          sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];

          igmp_membership_report_v3_t *igmp = vlib_buffer_get_current (b);
          ASSERT (igmp->header.type == IGMP_TYPE_membership_report_v3);
          len = sizeof (igmp_membership_report_v3_t);

          /* if interface (S,G)s were configured by CLI/API goto next frame */
          config = igmp_config_lookup (im, sw_if_index);
          if (config)
            {
              config->flags |= IGMP_CONFIG_FLAG_QUERY_RESP_RECVED;
              if (config->cli_api_configured)
                {
                  DBG ("Interface %u has (S,G)s configured by CLI/API",
                       sw_if_index);
                  error = IGMP_ERROR_CLI_API_CONFIG;
                  b->error = error_node->errors[error];
                  goto next_frame;
                }
            }
          DBG ("interface %u", sw_if_index);
          int i, j = 0;
          for (i = 0; i < clib_net_to_host_u16 (igmp->n_groups); i++)
            {
              group = group_ptr (igmp, len);
              src = group->src_addresses;
              if (group->type == IGMP_MEMBERSHIP_GROUP_mode_is_filter_include)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* update (S,G) expiration timer */
                      key.saddr.ip4 = *src;
                      key.gaddr.ip4 = group->dst_address;
                      sg = igmp_sg_lookup (config, &key);
                      if (sg)
                        sg->exp_time = vlib_time_now (vm) + IGMP_SG_TIMER;
                      src++;
                    }
                }
              else if (group->type ==
                       IGMP_MEMBERSHIP_GROUP_mode_is_filter_exclude)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* nothing for now... */
                      src++;
                    }
                }
              else if (group->type ==
                       IGMP_MEMBERSHIP_GROUP_change_to_filter_include)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* add new (S,G) to interface */
                      saddr.ip4 = *src;
                      gaddr.ip4 = group->dst_address;
                      igmp_listen (vm, 1, sw_if_index, saddr, gaddr, 0);
                      src++;
                    }
                }
              else if (group->type ==
                       IGMP_MEMBERSHIP_GROUP_change_to_filter_exclude)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* remove (S,G) from interface */
                      saddr.ip4 = *src;
                      gaddr.ip4 = group->dst_address;
                      igmp_listen (vm, 0, sw_if_index, saddr, gaddr, 0);
                      src++;
                    }
                }
              else if (group->type == IGMP_MEMBERSHIP_GROUP_allow_new_sources)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* nothing for now... */
                      src++;
                    }
                }
              else if (group->type == IGMP_MEMBERSHIP_GROUP_block_old_sources)
                {
                  for (j = 0;
                       j < clib_net_to_host_u16 (group->n_src_addresses); j++)
                    {
                      /* remove (S,G) from interface */
                      saddr.ip4 = *src;
                      gaddr.ip4 = group->dst_address;
                      igmp_listen (vm, 0, sw_if_index, saddr, gaddr, 0);
                      src++;
                    }
                }
              /*
               * Unrecognized Record Type values MUST be silently ignored.
               */

              /* move ptr to next Group Record */
              len +=
                sizeof (igmp_membership_group_v3_t) +
                (sizeof (ip4_address_t) * j);
            }
        next_frame:
          if (node->flags & VLIB_NODE_FLAG_TRACE)
            {
              igmp_input_trace_t *tr;
              tr = vlib_add_trace (vm, node, b, sizeof (*tr));
              tr->next_index = next;
              tr->sw_if_index = vnet_buffer (b)->sw_if_index[VLIB_RX];
              clib_memcpy (tr->packet_data, vlib_buffer_get_current (b),
                           sizeof (tr->packet_data));
            }
          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
                                           n_left_to_next, bi, next);
        }
      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
    }

  return frame->n_vectors;
}

/* *INDENT-OFF* */
VLIB_REGISTER_NODE (igmp_parse_report_node) =
{
  .function = igmp_parse_report,
  .name = "igmp-parse-report",
  .vector_size = sizeof (u32),

  .format_buffer = format_igmp_report_v3,
  .format_trace = format_igmp_parse_report_trace,

  .n_errors = IGMP_N_ERROR,
  .error_strings = igmp_error_strings,

  .n_next_nodes = IGMP_PARSE_REPORT_N_NEXT,
  .next_nodes = {
    [IGMP_PARSE_REPORT_NEXT_DROP] = "error-drop",
  }
};
/* *INDENT-ON* */

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