text: /*
   * Copyright (c) 2015 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.
   */
  /*
   * srp_interface.c: srp interfaces
   *
   * Copyright (c) 2008 Eliot Dresselhaus
   *
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sublicense, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   *
   * The above copyright notice and this permission notice shall be
   * included in all copies or substantial portions of the Software.
   *
   *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   */
  
  #include <vnet/vnet.h>
  #include <vnet/pg/pg.h>
  #include <vnet/srp/srp.h>
  
  static u8*
  srp_build_rewrite (vnet_main_t * vnm,
  		   u32 sw_if_index,
  		   vnet_link_t link_type,
  		   const void * dst_address)
  {
    vnet_hw_interface_t * hw = vnet_get_sup_hw_interface (vnm, sw_if_index);
    srp_main_t * sm = &srp_main;
    srp_and_ethernet_header_t * h;
    u8* rewrite = NULL;
    u16 type;
    uword n_bytes = sizeof (h[0]);
  
    switch (link_type) {
  #define _(a,b) case VNET_LINK_##a: type = ETHERNET_TYPE_##b; break
      _ (IP4, IP4);
      _ (IP6, IP6);
      _ (MPLS, MPLS);
      _ (ARP, ARP);
  #undef _
    default:
        return (NULL);
    }
  
    vec_validate(rewrite, n_bytes-1);
    h = (srp_and_ethernet_header_t *)rewrite;
  
    clib_memcpy (h->ethernet.src_address, hw->hw_address, sizeof (h->ethernet.src_address));
    if (dst_address)
      clib_memcpy (h->ethernet.dst_address, dst_address, sizeof (h->ethernet.dst_address));
    else
      memset (h->ethernet.dst_address, ~0, sizeof (h->ethernet.dst_address)); /* broadcast */
  
    h->ethernet.type = clib_host_to_net_u16 (type);
  
    h->srp.as_u16 = 0;
    h->srp.mode = SRP_MODE_data;
    h->srp.ttl = sm->default_data_ttl;
    srp_header_compute_parity (&h->srp);
  
    return (rewrite);
  }
  
  static void srp_register_interface_helper (u32 * hw_if_indices_by_side, u32 redistribute);
  
  void serialize_srp_main (serialize_main_t * m, va_list * va)
  {
    srp_main_t * sm = &srp_main;
    srp_interface_t * si;
  
    serialize_integer (m, pool_elts (sm->interface_pool), sizeof (u32));
    pool_foreach (si, sm->interface_pool, ({
      serialize_integer (m, si->rings[SRP_RING_OUTER].hw_if_index, sizeof (u32));
      serialize_integer (m, si->rings[SRP_RING_INNER].hw_if_index, sizeof (u32));
    }));
  }
  
  void unserialize_srp_main (serialize_main_t * m, va_list * va)
  {
    u32 i, n_ifs, hw_if_indices[SRP_N_RING];
  
    unserialize_integer (m, &n_ifs, sizeof (u32));
    for (i = 0; i < n_ifs; i++)
      {
        unserialize_integer (m, &hw_if_indices[SRP_RING_OUTER], sizeof (u32));
        unserialize_integer (m, &hw_if_indices[SRP_RING_INNER], sizeof (u32));
        srp_register_interface_helper (hw_if_indices, /* redistribute */ 0);
      }
  }
  
  static void serialize_srp_register_interface_msg (serialize_main_t * m, va_list * va)
  {
    u32 * hw_if_indices = va_arg (*va, u32 *);
    serialize_integer (m, hw_if_indices[SRP_SIDE_A], sizeof (hw_if_indices[SRP_SIDE_A]));
    serialize_integer (m, hw_if_indices[SRP_SIDE_B], sizeof (hw_if_indices[SRP_SIDE_B]));
  }
  
  static void unserialize_srp_register_interface_msg (serialize_main_t * m, va_list * va)
  {
    CLIB_UNUSED (mc_main_t * mcm) = va_arg (*va, mc_main_t *);
    u32 hw_if_indices[SRP_N_SIDE];
    srp_main_t * sm = &srp_main;
    uword * p;
  
    unserialize_integer (m, &hw_if_indices[SRP_SIDE_A], sizeof (hw_if_indices[SRP_SIDE_A]));
    unserialize_integer (m, &hw_if_indices[SRP_SIDE_B], sizeof (hw_if_indices[SRP_SIDE_B]));
  
    p = hash_get (sm->srp_register_interface_waiting_process_pool_index_by_hw_if_index,
  		hw_if_indices[0]);
    if (p)
      {
        vlib_one_time_waiting_process_t * wp = pool_elt_at_index (sm->srp_register_interface_waiting_process_pool, p[0]);
        vlib_signal_one_time_waiting_process (mcm->vlib_main, wp);
        pool_put (sm->srp_register_interface_waiting_process_pool, wp);
        hash_unset (sm->srp_register_interface_waiting_process_pool_index_by_hw_if_index,
  		  hw_if_indices[0]);
      }
    else
      srp_register_interface_helper (hw_if_indices, /* redistribute */ 0);
  }
  
  MC_SERIALIZE_MSG (srp_register_interface_msg, static) = {
    .name = "vnet_srp_register_interface",
    .serialize = serialize_srp_register_interface_msg,
    .unserialize = unserialize_srp_register_interface_msg,
  };
  
  static void srp_register_interface_helper (u32 * hw_if_indices_by_side, u32 redistribute)
  {
    vnet_main_t * vnm = vnet_get_main();
    srp_main_t * sm = &srp_main;
    vlib_main_t * vm = sm->vlib_main;
    srp_interface_t * si;
    vnet_hw_interface_t * hws[SRP_N_RING];
    uword s, * p;
  
    if (vm->mc_main && redistribute)
      {
        vlib_one_time_waiting_process_t * wp;
        mc_serialize (vm->mc_main, &srp_register_interface_msg, hw_if_indices_by_side);
        pool_get (sm->srp_register_interface_waiting_process_pool, wp);
        hash_set (sm->srp_register_interface_waiting_process_pool_index_by_hw_if_index,
  		hw_if_indices_by_side[0],
  		wp - sm->srp_register_interface_waiting_process_pool);
        vlib_current_process_wait_for_one_time_event (vm, wp);
      }
  
    /* Check if interface has already been registered. */
    p = hash_get (sm->interface_index_by_hw_if_index, hw_if_indices_by_side[0]);
    if (p)
      {
        si = pool_elt_at_index (sm->interface_pool, p[0]);
      }
    else
      {
        pool_get (sm->interface_pool, si);
        memset (si, 0, sizeof (si[0]));
      }
    for (s = 0; s < SRP_N_SIDE; s++)
      {
        hws[s] = vnet_get_hw_interface (vnm, hw_if_indices_by_side[s]);
        si->rings[s].ring = s;
        si->rings[s].hw_if_index = hw_if_indices_by_side[s];
        si->rings[s].sw_if_index = hws[s]->sw_if_index;
        hash_set (sm->interface_index_by_hw_if_index, hw_if_indices_by_side[s], si - sm->interface_pool);
      }
  
    /* Inherit MAC address from outer ring. */
    clib_memcpy (si->my_address, hws[SRP_RING_OUTER]->hw_address,
  	  vec_len (hws[SRP_RING_OUTER]->hw_address));
  
    /* Default time to wait to restore signal. */
    si->config.wait_to_restore_idle_delay = 60;
    si->config.ips_tx_interval = 1;
  }
  
  void srp_register_interface (u32 * hw_if_indices_by_side)
  {
    srp_register_interface_helper (hw_if_indices_by_side, /* redistribute */ 1);
  }
  
  void srp_interface_set_hw_wrap_function (u32 hw_if_index, srp_hw_wrap_function_t * f)
  {
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
    si->hw_wrap_function = f;
  }
  
  void srp_interface_set_hw_enable_function (u32 hw_if_index, srp_hw_enable_function_t * f)
  {
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
    si->hw_enable_function = f;
  }
  
  void srp_interface_enable_ips (u32 hw_if_index)
  {
    srp_main_t * sm = &srp_main;
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
  
    si->ips_process_enable = 1;
  
    vlib_node_set_state (sm->vlib_main, srp_ips_process_node.index, VLIB_NODE_STATE_POLLING);
  }
  
  static uword
  srp_is_valid_class_for_interface (vnet_main_t * vnm, u32 hw_if_index, u32 hw_class_index)
  {
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
  
    if (! si)
      return 0;
  
    /* Both sides must be admin down. */
    if (vnet_sw_interface_is_admin_up (vnm, si->rings[SRP_RING_OUTER].sw_if_index))
      return 0;
    if (vnet_sw_interface_is_admin_up (vnm, si->rings[SRP_RING_INNER].sw_if_index))
      return 0;
  					 
    return 1;
  }
  
  static void
  srp_interface_hw_class_change (vnet_main_t * vnm, u32 hw_if_index,
  			       u32 old_hw_class_index, u32 new_hw_class_index)
  {
    srp_main_t * sm = &srp_main;
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
    vnet_hw_interface_t * hi;
    vnet_device_class_t * dc;
    u32 r, to_srp;
  
    if (!si) {
        clib_warning ("srp interface no set si = 0");
        return;
    }
  
    to_srp = new_hw_class_index == srp_hw_interface_class.index;
  
    /* Changing class on either outer or inner rings implies changing the class
       of the other. */
    for (r = 0; r < SRP_N_RING; r++)
      {
        srp_interface_ring_t * ir = &si->rings[r];
  
        hi = vnet_get_hw_interface (vnm, ir->hw_if_index);
        dc = vnet_get_device_class (vnm, hi->dev_class_index);
  
        /* hw_if_index itself will be handled by caller. */
        if (ir->hw_if_index != hw_if_index)
  	{
  	  vnet_hw_interface_init_for_class (vnm, ir->hw_if_index,
  					    new_hw_class_index,
  					    to_srp ? si - sm->interface_pool : ~0);
  
  	  if (dc->hw_class_change)
  	    dc->hw_class_change (vnm, ir->hw_if_index, new_hw_class_index);
  	}
        else
  	hi->hw_instance = to_srp ? si - sm->interface_pool : ~0;
      }
  
    if (si->hw_enable_function)
      si->hw_enable_function (si, /* enable */ to_srp);
  }
  
  VNET_HW_INTERFACE_CLASS (srp_hw_interface_class) = {
    .name = "SRP",
    .format_address = format_ethernet_address,
    .format_header = format_srp_header_with_length,
    .format_device = format_srp_device,
    .unformat_hw_address = unformat_ethernet_address,
    .unformat_header = unformat_srp_header,
    .build_rewrite = srp_build_rewrite,
    .update_adjacency = ethernet_update_adjacency,
    .is_valid_class_for_interface = srp_is_valid_class_for_interface,
    .hw_class_change = srp_interface_hw_class_change,
  };
  
  static void serialize_srp_interface_config_msg (serialize_main_t * m, va_list * va)
  {
    srp_interface_t * si = va_arg (*va, srp_interface_t *);
    srp_main_t * sm = &srp_main;
  
    ASSERT (! pool_is_free (sm->interface_pool, si));
    serialize_integer (m, si - sm->interface_pool, sizeof (u32));
    serialize (m, serialize_f64, si->config.wait_to_restore_idle_delay);
    serialize (m, serialize_f64, si->config.ips_tx_interval);
  }
  
  static void unserialize_srp_interface_config_msg (serialize_main_t * m, va_list * va)
  {
    CLIB_UNUSED (mc_main_t * mcm) = va_arg (*va, mc_main_t *);
    srp_main_t * sm = &srp_main;
    srp_interface_t * si;
    u32 si_index;
  
    unserialize_integer (m, &si_index, sizeof (u32));
    si = pool_elt_at_index (sm->interface_pool, si_index);
    unserialize (m, unserialize_f64, &si->config.wait_to_restore_idle_delay);
    unserialize (m, unserialize_f64, &si->config.ips_tx_interval);
  }
  
  MC_SERIALIZE_MSG (srp_interface_config_msg, static) = {
    .name = "vnet_srp_interface_config",
    .serialize = serialize_srp_interface_config_msg,
    .unserialize = unserialize_srp_interface_config_msg,
  };
  
  void srp_interface_get_interface_config (u32 hw_if_index, srp_interface_config_t * c)
  {
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
    ASSERT (si != 0);
    c[0] = si->config;
  }
  
  void srp_interface_set_interface_config (u32 hw_if_index, srp_interface_config_t * c)
  {
    srp_main_t * sm = &srp_main;
    vlib_main_t * vm = sm->vlib_main;
    srp_interface_t * si = srp_get_interface_from_vnet_hw_interface (hw_if_index);
    ASSERT (si != 0);
    if (memcmp (&si->config, &c[0], sizeof (c[0])))
      {
        si->config = c[0];
        if (vm->mc_main)
  	mc_serialize (vm->mc_main, &srp_interface_config_msg, si);
      }
  }
  
  #if DEBUG > 0
  
  #define VNET_SIMULATED_SRP_TX_NEXT_SRP_INPUT VNET_INTERFACE_TX_N_NEXT
  
  /* Echo packets back to srp input. */
  static uword
  simulated_srp_interface_tx (vlib_main_t * vm,
  			    vlib_node_runtime_t * node,
  			    vlib_frame_t * frame)
  {
    u32 n_left_from, n_left_to_next, n_copy, * from, * to_next;
    u32 next_index = VNET_SIMULATED_SRP_TX_NEXT_SRP_INPUT;
    u32 i;
    vlib_buffer_t * b;
  
    n_left_from = frame->n_vectors;
    from = vlib_frame_args (frame);
  
    while (n_left_from > 0)
      {
        vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  
        n_copy = clib_min (n_left_from, n_left_to_next);
  
        clib_memcpy (to_next, from, n_copy * sizeof (from[0]));
        n_left_to_next -= n_copy;
        n_left_from -= n_copy;
        for (i = 0; i < n_copy; i++)
  	{
  	  b = vlib_get_buffer (vm, from[i]);
  	  /* TX interface will be fake eth; copy to RX for benefit of srp-input. */
  	  b->sw_if_index[VLIB_RX] = b->sw_if_index[VLIB_TX];
  	}
  
        vlib_put_next_frame (vm, node, next_index, n_left_to_next);
      }
  
    return n_left_from;
  }
  
  static u8 * format_simulated_srp_name (u8 * s, va_list * args)
  {
    u32 dev_instance = va_arg (*args, u32);
    return format (s, "fake-srp%d", dev_instance);
  }
  
  VNET_DEVICE_CLASS (srp_simulated_device_class,static) = {
    .name = "Simulated srp",
    .format_device_name = format_simulated_srp_name,
    .tx_function = simulated_srp_interface_tx,
  };
  
  static clib_error_t *
  create_simulated_srp_interfaces (vlib_main_t * vm,
  				 unformat_input_t * input,
  				 vlib_cli_command_t * cmd)
  {
    vnet_main_t * vnm = vnet_get_main();
    u8 address[6];
    u32 hw_if_index;
    vnet_hw_interface_t * hi;
    static u32 instance;
  
    if (! unformat_user (input, unformat_ethernet_address, &address))
      {
        memset (address, 0, sizeof (address));
        address[0] = 0xde;
        address[1] = 0xad;
        address[5] = instance;
      }
  
    hw_if_index = vnet_register_interface (vnm,
  					 srp_simulated_device_class.index,
  					 instance++,
  					 srp_hw_interface_class.index, 0);
  
    hi = vnet_get_hw_interface (vnm, hw_if_index);
  
    srp_setup_node (vm, hi->output_node_index);
  
    hi->min_packet_bytes = 40 + 16;
  
    /* Standard default ethernet MTU. */
    hi->max_l3_packet_bytes[VLIB_RX] = hi->max_l3_packet_bytes[VLIB_TX] = 1500;
  
    vec_free (hi->hw_address);
    vec_add (hi->hw_address, address, sizeof (address));
  
    {
      uword slot;
  
      slot = vlib_node_add_named_next_with_slot
        (vm, hi->tx_node_index,
         "srp-input",
         VNET_SIMULATED_SRP_TX_NEXT_SRP_INPUT);
      ASSERT (slot == VNET_SIMULATED_SRP_TX_NEXT_SRP_INPUT);
    }
  
    return /* no error */ 0;
  }
  
  static VLIB_CLI_COMMAND (create_simulated_srp_interface_command) = {
    .path = "srp create-interfaces",
    .short_help = "Create simulated srp interface",
    .function = create_simulated_srp_interfaces,
  };
  #endif
  