l2t.c

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/*
 * 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 <vnet/vnet.h>
#include <vnet/ip/ip.h>
#include <vnet/ethernet/ethernet.h>

#if DPDK == 0
#include <vnet/devices/pci/ixge.h>
#else
#include <vnet/devices/dpdk/dpdk.h>
#endif

#include <vppinfra/error.h>
#include <vppinfra/hash.h>
#include <app/l2t.h>

l2t_main_t l2t_main;

/* $$$$ unused? 
 * get_interface_ethernet_address
 * paints the ethernet address for a given interface
 * into the supplied destination
 */
void get_interface_ethernet_address (l2t_main_t *lm, 
                                     u8 *dst, u32 sw_if_index)
{
    ethernet_main_t *em = ethernet_get_main (lm->vlib_main);
    ethernet_interface_t *ei;
    vnet_hw_interface_t *hi;

    hi = vnet_get_sup_hw_interface (lm->vnet_main, sw_if_index);
    ei = pool_elt_at_index (em->interfaces, hi->hw_instance);
    clib_memcpy (dst, ei->address, sizeof (ei->address));
}

/* packet trace format function */
u8 * format_l2t_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 *);
  l2t_trace_t * t = va_arg (*args, l2t_trace_t *);
    
  if (t->is_user_to_network)
      s = format (s, "L2T: %U (client) -> %U (our) session %d", 
                  format_ip6_address, &t->client_address,
                  format_ip6_address, &t->our_address,
                  t->session_index);
  else
      s = format (s, "L2T: %U (our) -> %U (client) session %d)",
                  format_ip6_address, &t->our_address,
                  format_ip6_address, &t->client_address,
                  t->session_index);
  return s;
}

u8 * format_l2t_session (u8 * s, va_list * args)
{
  l2t_session_t * session = va_arg (*args, l2t_session_t *);
  l2t_main_t * lm = &l2t_main;
  u32 counter_index;
  vlib_counter_t v;

  s = format (s, "[%d] %U (our) %U (client) vlan-id %d rx_sw_if_index %d\n", 
              session - lm->sessions,
              format_ip6_address, &session->our_address,
              format_ip6_address, &session->client_address,
              clib_net_to_host_u16(session->vlan_id), session->sw_if_index);

  s = format (s, "   local cookie %llx remote cookie %llx\n",
              clib_net_to_host_u64 (session->local_cookie),
              clib_net_to_host_u64 (session->remote_cookie));

  if (session->cookie_flags & L2TP_COOKIE_ROLLOVER_LOCAL) {
      s = format (s, "   local rollover cookie %llx\n", 
                  clib_net_to_host_u64 (session->lcl_ro_cookie));
  }

  s = format (s, "   local session-id %d remote session-id %d\n",
              clib_net_to_host_u32 (session->local_session_id),
              clib_net_to_host_u32 (session->remote_session_id));

  s = format (s, "   l2 specific sublayer %s\n", 
              session->l2_sublayer_present ? "preset" : "absent");

  counter_index = 
      session_index_to_counter_index (session - lm->sessions,
                                      SESSION_COUNTER_USER_TO_NETWORK);

  vlib_get_combined_counter (&lm->counter_main, counter_index, &v);
  if (v.packets != 0)
      s = format (s, "   user-to-net: %llu pkts %llu bytes\n",
                  v.packets, v.bytes);

  vlib_get_combined_counter (&lm->counter_main, counter_index+1, &v);

  if (v.packets != 0)
      s = format (s, "   net-to-user: %llu pkts %llu bytes\n",
                  v.packets, v.bytes);
  return s;
}

static clib_error_t *
show_session_summary_command_fn (vlib_main_t * vm,
                                unformat_input_t * input,
                                vlib_cli_command_t * cmd)
{
    l2t_main_t *lm = &l2t_main;
    
    vlib_cli_output (vm, "%d active sessions\n", pool_elts (lm->sessions));

    return 0;
}

static VLIB_CLI_COMMAND (show_session_summary_command) = {
    .path = "show session",
    .short_help = "show session summary",
    .function = show_session_summary_command_fn,
};

static clib_error_t *
show_session_detail_command_fn (vlib_main_t * vm,
                                unformat_input_t * input,
                                vlib_cli_command_t * cmd)
{
    l2t_session_t *session;
    l2t_main_t *lm = &l2t_main;

    pool_foreach (session, lm->sessions, 
    ({
        vlib_cli_output (vm, "%U", format_l2t_session, session);
    }));

    return 0;
}

static VLIB_CLI_COMMAND (show_session_detail_command) = {
    .path = "show session detail",
    .short_help = "show session table detail",
    .function = show_session_detail_command_fn,
};

static clib_error_t *
test_counters_command_fn (vlib_main_t * vm,
                          unformat_input_t * input,
                          vlib_cli_command_t * cmd)
{
    l2t_session_t *session;
    l2t_main_t *lm = &l2t_main;
    u32 session_index;
    u32 counter_index;
    u32 nincr=0;

    pool_foreach (session, lm->sessions, 
    ({
        session_index = session - lm->sessions;
        counter_index = 
            session_index_to_counter_index (session_index, 
                                            SESSION_COUNTER_USER_TO_NETWORK);
        vlib_increment_combined_counter (&lm->counter_main,
                                         counter_index, 
                                         1/*pkt*/, 1111 /*bytes*/);
        vlib_increment_combined_counter (&lm->counter_main,
                                         counter_index+1, 
                                         1/*pkt*/, 2222 /*bytes*/);
        nincr++;
        
    }));
    vlib_cli_output (vm, "Incremented %d active counters\n", nincr);

    return 0;
}

static VLIB_CLI_COMMAND (test_counters_command) = {
    .path = "test counters",
    .short_help = "increment all active counters",
    .function = test_counters_command_fn,
};

static clib_error_t *
clear_counters_command_fn (vlib_main_t * vm,
                          unformat_input_t * input,
                          vlib_cli_command_t * cmd)
{
    l2t_session_t *session;
    l2t_main_t *lm = &l2t_main;
    u32 session_index;
    u32 counter_index;
    u32 nincr=0;

    pool_foreach (session, lm->sessions, 
    ({
        session_index = session - lm->sessions;
        counter_index = 
            session_index_to_counter_index (session_index, 
                                            SESSION_COUNTER_USER_TO_NETWORK);
        vlib_zero_combined_counter (&lm->counter_main, counter_index);
        vlib_zero_combined_counter (&lm->counter_main, counter_index+1);
        nincr++;
        
    }));
    vlib_cli_output (vm, "Cleared %d active counters\n", nincr);

    return 0;
}

static VLIB_CLI_COMMAND (clear_counters_command) = {
    .path = "clear counters",
    .short_help = "clear all active counters",
    .function = clear_counters_command_fn,
};

static clib_error_t *
l2tp_session_add_command_fn (vlib_main_t * vm,
                             unformat_input_t * input,
                             vlib_cli_command_t * cmd)
{
    ip6_address_t client_address, our_address;
    ip6_address_t * dst_address_copy, * src_address_copy;
    unformat_input_t _line_input, * line_input = &_line_input;
    u32 vlan_id;
    u32 sw_if_index = (u32)~0;
    l2t_main_t *lm = &l2t_main;
    l2t_session_t *s;
    uword *p;
    vnet_hw_interface_t * hi;
    vnet_sw_interface_t * si;
    u32 next_index;
    uword vlan_and_sw_if_index_key;
    u32 counter_index;
    u64 local_cookie = (u64)~0, remote_cookie = (u64)~0;
    u32 local_session_id = 1, remote_session_id = 1;
    int our_address_set = 0, client_address_set = 0;
    int l2_sublayer_present = 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, "client %U", 
                      unformat_ip6_address, &client_address))
            client_address_set = 1;
        else if (unformat (line_input, "our %U",
                           unformat_ip6_address, &our_address))
            our_address_set = 1;
        else if (unformat (line_input, "vlan %d", &vlan_id))
            ;
        else if (unformat (line_input, "l2-interface %U",
                           unformat_vnet_sw_interface, 
                           vnet_get_main(), &sw_if_index))
            ;
        else if (unformat (line_input, "interface %U",
                           unformat_vnet_sw_interface, 
                           vnet_get_main(), &sw_if_index))
            ;
        else if (unformat (line_input, "local-cookie %llx", &local_cookie))
            ;
        else if (unformat (line_input, "remote-cookie %llx", &remote_cookie))
            ;
        else if (unformat (line_input, "local-session-id %d", 
                           &local_session_id))
            ;
        else if (unformat (line_input, "remote-session-id %d", 
                           &remote_session_id))
            ;
        else if (unformat (line_input, "l2-sublayer-present"))
            l2_sublayer_present = 1;
        else 
            return clib_error_return (0, "parse error: '%U'", 
                                      format_unformat_error, line_input);
    }

    unformat_free (line_input);

    if (sw_if_index == (u32)~0)
        return clib_error_return (0, "l2-interface not specified");
    if (our_address_set == 0)
        return clib_error_return (0, "our address not specified");
    if (client_address_set == 0)
        return clib_error_return (0, "client address not specified");

    remote_session_id = clib_host_to_net_u32 (remote_session_id);
    local_session_id  = clib_host_to_net_u32 (local_session_id);

    switch (lm->lookup_type) {
    case L2T_LOOKUP_SRC_ADDRESS:
        p = hash_get_mem (lm->session_by_src_address, &client_address);
        if (p) 
            return clib_error_return 
                (0, "Session w/ client address %U already exists",
                 format_ip6_address, &client_address);
        break;
        
    case L2T_LOOKUP_DST_ADDRESS:
        p = hash_get_mem (lm->session_by_dst_address, &our_address);
        if (p) 
            return clib_error_return 
                (0, "Session w/ our address %U already exists",
                 format_ip6_address, &our_address);
        break;

    case L2T_LOOKUP_SESSION_ID:
        p = hash_get (lm->session_by_session_id, local_session_id);
        if (p) 
            return clib_error_return 
                (0, 
                 "Session w/ local session id %d already exists",
                 clib_net_to_host_u32 (local_session_id));
        break;

    default:
        ASSERT(0);
    }
    
    pool_get (lm->sessions, s);
    memset (s, 0, sizeof (*s));
    clib_memcpy (&s->our_address, &our_address, sizeof (s->our_address));
    clib_memcpy (&s->client_address, &client_address, sizeof (s->client_address));
    s->sw_if_index = sw_if_index;
    s->vlan_id = clib_host_to_net_u16 (vlan_id);
    s->local_cookie = clib_host_to_net_u64 (local_cookie);
    l2tp_session_set_remote_cookie (s, remote_cookie);
    s->local_session_id = local_session_id;
    s->remote_session_id = remote_session_id;
    s->l2_sublayer_present = l2_sublayer_present;
    
    hi = vnet_get_sup_hw_interface (lm->vnet_main, sw_if_index);
    si = vnet_get_sup_sw_interface (lm->vnet_main, sw_if_index);

    next_index = vlib_node_add_next (vm, l2t_ip6_node.index,
                                     hi->output_node_index);
    s->l2_output_next_index = next_index;
    s->l2_output_sw_if_index = si->sw_if_index;

    /* Setup hash table entries */
    switch (lm->lookup_type) {
    case L2T_LOOKUP_SRC_ADDRESS:
        src_address_copy = clib_mem_alloc (sizeof (*src_address_copy));
        clib_memcpy (src_address_copy, &client_address, sizeof (*src_address_copy));
        hash_set_mem (lm->session_by_src_address, src_address_copy, 
                      s - lm->sessions);
        break;
    case L2T_LOOKUP_DST_ADDRESS:
        dst_address_copy = clib_mem_alloc (sizeof (*dst_address_copy));
        clib_memcpy (dst_address_copy, &our_address, sizeof (*dst_address_copy));
        hash_set_mem (lm->session_by_dst_address, dst_address_copy, 
                      s - lm->sessions);
        break;
    case L2T_LOOKUP_SESSION_ID:
        hash_set (lm->session_by_session_id, local_session_id, 
                  s - lm->sessions);
        break;

    default:
        ASSERT(0);
    }

    vlan_and_sw_if_index_key = ((uword)(s->vlan_id)<<32) | sw_if_index;
    hash_set (lm->session_by_vlan_and_rx_sw_if_index,
              vlan_and_sw_if_index_key, s - lm->sessions);
    
    /* validate counters */
    counter_index = 
        session_index_to_counter_index (s - lm->sessions,
                                        SESSION_COUNTER_USER_TO_NETWORK);
    vlib_validate_counter (&lm->counter_main, counter_index);
    vlib_validate_counter (&lm->counter_main, counter_index+1);
        
    /* Set promiscuous mode on the l2 interface */
    ethernet_set_flags (lm->vnet_main, hi->hw_if_index, 
                        ETHERNET_INTERFACE_FLAG_ACCEPT_ALL);
    vnet_hw_interface_rx_redirect_to_node (lm->vnet_main, hi->hw_if_index,
                                           l2t_l2_node.index);
    return 0;
}

static VLIB_CLI_COMMAND (l2tp_session_add_command) = {
    .path = "l2tp session add",
    .short_help = 
    "l2tp session add client <ip6> our <ip6> vlan <id> local-cookie <hex> remote-cookie <hex> local-session <dec> remote-session <dec> l2-interface <int>",
    .function = l2tp_session_add_command_fn,
};

static clib_error_t *
l2tp_session_del_command_fn (vlib_main_t * vm,
                             unformat_input_t * input,
                             vlib_cli_command_t * cmd)
{
    l2t_main_t *lm = &l2t_main;
    u32 session_index;
    l2t_session_t *s;
    hash_pair_t * hp;
    void *key;
    uword vlan_and_sw_if_index_key;

    if (!unformat (input, "%d", &session_index)) 
        return clib_error_return (0, "missing session index: '%U'", 
                                  format_unformat_error, input);
        
    if (pool_is_free_index (lm->sessions, session_index))
        return clib_error_return (0, "session %d not in use", session_index);

    s = pool_elt_at_index (lm->sessions, session_index);

    switch (lm->lookup_type) {
    case L2T_LOOKUP_SRC_ADDRESS:
        hp = hash_get_pair_mem (lm->session_by_src_address, &s->client_address);
        if (hp) {
            key = (void *)(hp->key);
            hash_unset_mem (lm->session_by_src_address, &s->client_address);
            clib_mem_free (key);
        } else
            clib_warning ("session %d src address key %U AWOL", 
                          s - lm->sessions, 
                          format_ip6_address, &s->client_address);
        break;

    case L2T_LOOKUP_DST_ADDRESS:
        hp = hash_get_pair_mem (lm->session_by_dst_address, &s->our_address);
        if (hp) {
            key = (void *)(hp->key);
            hash_unset_mem (lm->session_by_dst_address, &s->our_address);
            clib_mem_free (key);
        } else
            clib_warning ("session %d dst address key %U AWOL", 
                          s - lm->sessions, 
                          format_ip6_address, &s->our_address);
        break;

    case L2T_LOOKUP_SESSION_ID:
        hash_unset (lm->session_by_session_id, s->local_session_id);
        break;
        
    default:
        ASSERT(0);
    }
        
    vlan_and_sw_if_index_key = ((uword)(s->vlan_id)<<32) | s->sw_if_index;

    hash_unset (lm->session_by_vlan_and_rx_sw_if_index, vlan_and_sw_if_index_key);
        
    pool_put (lm->sessions, s);
    return 0;
}

static VLIB_CLI_COMMAND (l2tp_session_del_command) = {
    .path = "l2tp session delete",
    .short_help = 
    "l2tp session delete <session-id>",
    .function = l2tp_session_del_command_fn,
};

static clib_error_t *
l2tp_session_cookie_command_fn (vlib_main_t * vm,
                                unformat_input_t * input,
                                vlib_cli_command_t * cmd)
{
    l2t_main_t *lm = &l2t_main;
    u32 session_index;
    l2t_session_t *s;
    u64 lcl_ro_cookie = (u64)~0, rem_ro_cookie = (u64)~0;
    u8 cookie_flags = 0;

    if (!unformat (input, "%d", &session_index)) 
        return clib_error_return (0, "missing session index: '%U'", 
                                  format_unformat_error, input);
        
    if (pool_is_free_index (lm->sessions, session_index))
        return clib_error_return (0, "session %d not in use", session_index);

    s = pool_elt_at_index (lm->sessions, session_index);

    if (unformat (input, "commit")) {
        if (!s->cookie_flags) {
            return clib_error_return (0,
                                      "no rollover cookie ready to commit");
        } else {
            l2tp_session_cookie_commit (s);
            return 0;
        }
    }
    if (!unformat (input, "rollover"))
        return clib_error_return (0, "missing 'commit|rollover': '%U'", 
                                  format_unformat_error, input);
    if (unformat (input, "local %llx", &lcl_ro_cookie)) {
        cookie_flags |= L2TP_COOKIE_ROLLOVER_LOCAL;
        l2tp_session_set_local_rollover_cookie (s, lcl_ro_cookie);
    }
    if (unformat (input, "remote %llx", &rem_ro_cookie)) {
        cookie_flags |= L2TP_COOKIE_ROLLOVER_REMOTE;
        l2tp_session_set_remote_cookie (s, rem_ro_cookie);
    }
    if (!cookie_flags)
        return clib_error_return (0, "no rollover cookie specified");

    return 0;
}

static VLIB_CLI_COMMAND (l2tp_session_cookie_command) = {
    .path = "l2tp session cookie",
    .short_help = 
    "l2tp session cookie <session id> commit|rollover [local <hex>] [remote <hex>]",
    .function = l2tp_session_cookie_command_fn,
};