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.
   */
  
  #include "sixrd.h"
  #include <vnet/plugin/plugin.h>
  
  #include <vnet/fib/fib_table.h>
  #include <vnet/fib/ip6_fib.h>
  #include <vnet/adj/adj.h>
  
  /*
   * This code supports the following sixrd modes:
   * 
   * 32 EA bits (Complete IPv4 address is embedded):
   *   ea_bits_len = 32
   * IPv4 suffix is embedded:
   *   ea_bits_len = < 32
   * No embedded address bits (1:1 mode):
   *   ea_bits_len = 0
   */
  
  int
  sixrd_create_domain (ip6_address_t *ip6_prefix,
  		     u8 ip6_prefix_len,
  		     ip4_address_t *ip4_prefix,
  		     u8 ip4_prefix_len,
  		     ip4_address_t *ip4_src,
  		     u32 *sixrd_domain_index,
  		     u16 mtu)
  {
    dpo_id_t dpo_v6 = DPO_INVALID, dpo_v4 = DPO_INVALID;
    sixrd_main_t *mm = &sixrd_main;
    fib_node_index_t fei;
    sixrd_domain_t *d;
  
    /* Get domain index */
    pool_get_aligned(mm->domains, d, CLIB_CACHE_LINE_BYTES);
    memset(d, 0, sizeof (*d));
    *sixrd_domain_index = d - mm->domains;
  
    /* Init domain struct */
    d->ip4_prefix.as_u32 = ip4_prefix->as_u32;
    d->ip4_prefix_len = ip4_prefix_len;
    d->ip6_prefix = *ip6_prefix;
    d->ip6_prefix_len = ip6_prefix_len;
    d->ip4_src = *ip4_src;
    d->mtu = mtu;
  
    if (ip4_prefix_len < 32)
      d->shift = 64 - ip6_prefix_len + (32 - ip4_prefix_len);
      
    /* Create IPv6 route/adjacency */
    fib_prefix_t pfx6 = {
        .fp_proto = FIB_PROTOCOL_IP6,
        .fp_len = d->ip6_prefix_len,
        .fp_addr = {
  	  .ip6 = d->ip6_prefix,
        },
    };
    sixrd_dpo_create(DPO_PROTO_IP6,
  		   *sixrd_domain_index,
  		   &dpo_v6);
    fib_table_entry_special_dpo_add(0, &pfx6,
  				  FIB_SOURCE_SIXRD,
  				  FIB_ENTRY_FLAG_EXCLUSIVE,
  				  &dpo_v6);
    dpo_reset (&dpo_v6);
  
    /*
     * Multiple SIXRD domains may share same source IPv4 TEP
     * In this case the route will exist and be SixRD sourced.
     * Find the adj (if any) already contributed and modify it
     */
    fib_prefix_t pfx4 = {
        .fp_proto = FIB_PROTOCOL_IP4,
        .fp_len = 32,
        .fp_addr = {
  	  .ip4 = d->ip4_src,
        },
    };
    fei = fib_table_lookup_exact_match(0, &pfx4);
  
    if (FIB_NODE_INDEX_INVALID != fei)
    {
        dpo_id_t dpo = DPO_INVALID;
  
        if (fib_entry_get_dpo_for_source (fei, FIB_SOURCE_SIXRD, &dpo))
        {
  	  /*
  	   * modify the existing adj to indicate it's shared
  	   * skip to route add.
  	   * It is locked to pair with the unlock below.
  	   */
  	  const dpo_id_t *sd_dpo;
  	  sixrd_dpo_t *sd;
  
  	  ASSERT(DPO_LOAD_BALANCE == dpo.dpoi_type);
  
  	  sd_dpo = load_balance_get_bucket(dpo.dpoi_index, 0);
  	  sd = sixrd_dpo_get (sd_dpo->dpoi_index);
  
  	  sd->sd_domain = ~0;
  	  dpo_copy (&dpo_v4, sd_dpo);
  	  dpo_reset (&dpo);
  
  	  goto route_add;
        }
    }
    /* first time addition of the route */
    sixrd_dpo_create(DPO_PROTO_IP4,
  		   *sixrd_domain_index,
  		   &dpo_v4);
  
  route_add:
    /*
     * Create ip4 route. This is a reference counted add. If the prefix
     * already exists and is SixRD sourced, it is now SixRD source n+1 times
     * and will need to be removed n+1 times.
     */
    fib_table_entry_special_dpo_add(0, &pfx4,
  				  FIB_SOURCE_SIXRD,
  				  FIB_ENTRY_FLAG_EXCLUSIVE,
  				  &dpo_v4);
    dpo_reset (&dpo_v4);
  
    return 0;
  }
  
  /*
   * sixrd_delete_domain
   */
  int
  sixrd_delete_domain (u32 sixrd_domain_index)
  {
    sixrd_main_t *mm = &sixrd_main;
    sixrd_domain_t *d;
  
    if (pool_is_free_index(mm->domains, sixrd_domain_index)) {
      clib_warning("SIXRD domain delete: domain does not exist: %d",
  		 sixrd_domain_index);
      return -1;
    }
  
    d = pool_elt_at_index(mm->domains, sixrd_domain_index);
  
    fib_prefix_t pfx = {
        .fp_proto = FIB_PROTOCOL_IP4,
        .fp_len = 32,
        .fp_addr = {
  	  .ip4 = d->ip4_src,
        },
    };
    fib_table_entry_special_remove(0, &pfx, FIB_SOURCE_SIXRD);
  
    fib_prefix_t pfx6 = {
        .fp_proto = FIB_PROTOCOL_IP6,
        .fp_len = d->ip6_prefix_len,
        .fp_addr = {
  	  .ip6 = d->ip6_prefix,
        },
    };
    fib_table_entry_special_remove(0, &pfx6, FIB_SOURCE_SIXRD);
  
    pool_put(mm->domains, d);
  
    return 0;
  }
  
  static clib_error_t *
  sixrd_add_domain_command_fn (vlib_main_t *vm,
                             unformat_input_t *input,
                             vlib_cli_command_t *cmd)
  {
    unformat_input_t _line_input, *line_input = &_line_input;
    ip4_address_t ip4_prefix;
    ip6_address_t ip6_prefix;
    ip4_address_t ip4_src;
    u32 ip6_prefix_len=0, ip4_prefix_len=0, sixrd_domain_index;
    u32 num_m_args = 0;
    /* Optional arguments */
    u32 mtu = 0;
  
    /* Get a line of input. */
    if (!unformat_user(input, unformat_line_input, line_input))
      return 0;
    while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT) {
      if (unformat(line_input, "ip6-pfx %U/%d", unformat_ip6_address, &ip6_prefix, &ip6_prefix_len))
        num_m_args++;
      else if (unformat(line_input, "ip4-pfx %U/%d", unformat_ip4_address, &ip4_prefix, &ip4_prefix_len))
        num_m_args++;
      else if (unformat(line_input, "ip4-src %U", unformat_ip4_address, &ip4_src))
        num_m_args++;
      else if (unformat(line_input, "mtu %d", &mtu))
        num_m_args++;
      else
        return clib_error_return(0, "unknown input `%U'",
                                 format_unformat_error, input);
    }
    unformat_free(line_input);
  
    if (num_m_args < 3)
      return clib_error_return(0, "mandatory argument(s) missing");
  
    sixrd_create_domain(&ip6_prefix, ip6_prefix_len, &ip4_prefix, ip4_prefix_len,
  		      &ip4_src, &sixrd_domain_index, mtu);
  
    return 0;
  }
  
  static clib_error_t *
  sixrd_del_domain_command_fn (vlib_main_t *vm,
  			   unformat_input_t *input,
  			   vlib_cli_command_t *cmd)
  {
    unformat_input_t _line_input, *line_input = &_line_input;
    u32 num_m_args = 0;
    u32 sixrd_domain_index;
  
    /* Get a line of input. */
    if (! unformat_user(input, unformat_line_input, line_input))
      return 0;
   
    while (unformat_check_input(line_input) != UNFORMAT_END_OF_INPUT) {
      if (unformat(line_input, "index %d", &sixrd_domain_index))
        num_m_args++;
      else
        return clib_error_return(0, "unknown input `%U'",
  				format_unformat_error, input);
    }
    unformat_free(line_input);
  
    if (num_m_args != 1)
      return clib_error_return(0, "mandatory argument(s) missing");
  
    sixrd_delete_domain(sixrd_domain_index);
  
    return 0;
  }
  
  static u8 *
  format_sixrd_domain (u8 *s, va_list *args)
  {
    sixrd_domain_t *d = va_arg(*args, sixrd_domain_t *);
    sixrd_main_t *mm = &sixrd_main;
  
    s = format(s,
  	     "[%d] ip6-pfx %U/%d ip4-pfx %U/%d ip4-src %U mtu %d",
  	     d - mm->domains,
  	     format_ip6_address, &d->ip6_prefix, d->ip6_prefix_len,
  	     format_ip4_address, &d->ip4_prefix, d->ip4_prefix_len,
  	     format_ip4_address, &d->ip4_src, d->mtu);
  
    return s;
  }
  
  static clib_error_t *
  show_sixrd_domain_command_fn (vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
  {
    sixrd_main_t *mm = &sixrd_main;
    sixrd_domain_t *d;
  
    if (pool_elts(mm->domains) == 0)
      vlib_cli_output(vm, "No SIXRD domains are configured...");
  
    pool_foreach(d, mm->domains, ({vlib_cli_output(vm, "%U", format_sixrd_domain, d);}));
  
    return 0;
  
  }
  
  static clib_error_t *
  show_sixrd_stats_command_fn (vlib_main_t *vm, unformat_input_t *input, vlib_cli_command_t *cmd)
  {
    sixrd_main_t *mm = &sixrd_main;
    sixrd_domain_t *d;
    int domains = 0, domaincount = 0;
    if (pool_elts (mm->domains) == 0)
      vlib_cli_output (vm, "No SIXRD domains are configured...");
  
    pool_foreach(d, mm->domains, ({
      domains += sizeof(*d);
      domaincount++;
    }));
  
    vlib_cli_output(vm, "SIXRD domains structure: %d\n", sizeof (sixrd_domain_t));
    vlib_cli_output(vm, "SIXRD domains: %d (%d bytes)\n", domaincount, domains);
  
    return 0;
  }
  
  /*
   * packet trace format function
   */
  u8 *
  format_sixrd_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 *);
    sixrd_trace_t *t = va_arg (*args, sixrd_trace_t *);
    u32 sixrd_domain_index = t->sixrd_domain_index;
  
    s = format(s, "SIXRD domain index: %d", sixrd_domain_index);
  
    return s;
  }
  
  VLIB_CLI_COMMAND(sixrd_add_domain_command, static) = {
    .path = "sixrd add domain",
    .short_help = 
    "sixrd add domain ip6-pfx <ip6-pfx> ip4-pfx <ip4-pfx> ip4-src <ip4-addr>",
    .function = sixrd_add_domain_command_fn,
  };
  
  VLIB_CLI_COMMAND(sixrd_del_command, static) = {
    .path = "sixrd del domain",
    .short_help = 
    "sixrd del domain index <domain>",
    .function = sixrd_del_domain_command_fn,
  };
  
  VLIB_CLI_COMMAND(show_sixrd_domain_command, static) = {
    .path = "show sixrd domain",
    .function = show_sixrd_domain_command_fn,
  };
  
  VLIB_CLI_COMMAND(show_sixrd_stats_command, static) = {
    .path = "show sixrd stats",
    .function = show_sixrd_stats_command_fn,
  };
  
  /* 
   * This routine exists to convince the vlib plugin framework that
   * we haven't accidentally copied a random .dll into the plugin directory.
   *
   * Also collects global variable pointers passed from the vpp engine
   */
  clib_error_t * 
  vlib_plugin_register (vlib_main_t * vm, vnet_plugin_handoff_t * h,
                        int from_early_init)
  {
    clib_error_t * error = 0;
    sixrd_main_t *mm = &sixrd_main;
  
    mm->vnet_main = vnet_get_main();
    mm->vlib_main = vm;
  
    return error;
  }
  
  static clib_error_t * sixrd_init (vlib_main_t * vm)
  {
    sixrd_dpo_module_init ();
  
    return (NULL);
  }
  
  VLIB_INIT_FUNCTION (sixrd_init);
  