src/plugins/sixrd/ip4_sixrd.c

   1 /*---------------------------------------------------------------------------
   2  * Copyright (c) 2009-2014 Cisco and/or its affiliates.
   3  * Licensed under the Apache License, Version 2.0 (the "License");
   4  * you may not use this file except in compliance with the License.
   5  * You may obtain a copy of the License at:
   6  *
   7  *     http://www.apache.org/licenses/LICENSE-2.0
   8  *
   9  * Unless required by applicable law or agreed to in writing, software
  10  * distributed under the License is distributed on an "AS IS" BASIS,
  11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12  * See the License for the specific language governing permissions and
  13  * limitations under the License.
  14  *---------------------------------------------------------------------------
  15  */
  16
  17 #include "sixrd.h"
  18
  19 vlib_node_registration_t ip4_sixrd_node;
  20
  21 typedef enum {
  22   IP4_SIXRD_NEXT_IP6_LOOKUP,
  23   IP4_SIXRD_NEXT_DROP,
  24   IP4_SIXRD_N_NEXT,
  25 } ip4_sixrd_next_t;
  26
  27 typedef struct {
  28   u32 tunnel_id;
  29   u32 length;
  30   ip4_address_t src;
  31   ip4_address_t dst;
  32 } sixrd_rx_trace_t;
  33
  34 u8 *
  35 format_sixrd_rx_trace (u8 * s, va_list * args)
  36 {
  37   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  38   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  39   sixrd_rx_trace_t *t = va_arg (*args, sixrd_rx_trace_t *);
  40
  41   s = format (s, "6RD: tunnel %d len %d src %U dst %U",
  42               t->tunnel_id, clib_net_to_host_u16 (t->length),
  43               format_ip4_address, &t->src, format_ip4_address, &t->dst);
  44   return s;
  45 }
  46
  47 /*
  48  * ip4_sixrd_sec_check
  49  */
  50 static_always_inline void
  51 ip4_sixrd_sec_check(sixrd_tunnel_t *t, ip4_address_t sa4,
  52                     ip6_address_t sa6, u8 *error) {
  53   if (PREDICT_FALSE(sixrd_get_addr_net(t, sa6.as_u64[0]) != sa4.as_u32))
  54     *error = SIXRD_ERROR_SEC_CHECK;
  55 }
  56
  57 /*
  58  * ip4_sixrd
  59  */
  60 uword ip4_sixrd(vlib_main_t *vm, vlib_node_runtime_t *node,
  61                 vlib_frame_t *frame) {
  62   u32 n_left_from, *from, next_index, *to_next, n_left_to_next;
  63   vlib_node_runtime_t *error_node = vlib_node_get_runtime(vm, ip4_sixrd_node.index);
  64   vnet_interface_main_t * im = &vnet_get_main()->interface_main;
  65   u32 thread_index = vlib_get_thread_index ();
  66
  67   from = vlib_frame_vector_args(frame);
  68   n_left_from = frame->n_vectors;
  69   next_index = node->cached_next_index;
  70   while (n_left_from > 0) {
  71     vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
  72
  73     /* Single loop */
  74     while (n_left_from > 0 && n_left_to_next > 0) {
  75       u32 pi0;
  76       vlib_buffer_t *p0;
  77       u8 error0 = SIXRD_ERROR_NONE;
  78       sixrd_tunnel_t *t0 = 0;
  79       ip4_header_t *ip40;
  80       ip6_header_t *ip60;
  81       u32 tunnel_sw_if_index = ~0;
  82       u32 next0 = IP4_SIXRD_NEXT_DROP;
  83
  84       pi0 = to_next[0] = from[0];
  85       from += 1;
  86       n_left_from -= 1;
  87       to_next += 1;
  88       n_left_to_next -= 1;
  89
  90       p0 = vlib_get_buffer(vm, pi0);
  91       ip40 = vlib_buffer_get_current(p0);
  92
  93       /* Throw away anything that isn't IP in IP. */
  94       if (PREDICT_TRUE(ip40->protocol == IP_PROTOCOL_IPV6 && clib_net_to_host_u16(ip40->length) >= 60)) {
  95         vlib_buffer_advance(p0, sizeof(ip4_header_t));
  96         t0 = ip4_sixrd_get_tunnel(vnet_buffer(p0)->ip.adj_index[VLIB_TX], (ip4_address_t *)&ip40->dst_address, &error0);
  97       } else {
  98         error0 = SIXRD_ERROR_BAD_PROTOCOL;
  99       }
 100
 101       if (!t0) {
 102         error0 = SIXRD_ERROR_NO_TUNNEL;
 103         goto error;
 104       }
 105
 106       tunnel_sw_if_index = t0->sw_if_index;
 107
 108       /* SIXRD inbound security check */
 109       if (t0->security_check) {
 110         ip60 = vlib_buffer_get_current(p0);
 111         ip4_sixrd_sec_check(t0, ip40->src_address, ip60->src_address, &error0);
 112       }
 113       next0 = error0 == SIXRD_ERROR_NONE ? IP4_SIXRD_NEXT_IP6_LOOKUP
 114                                          : IP4_SIXRD_NEXT_DROP;
 115
 116       if (PREDICT_FALSE(p0->flags & VLIB_BUFFER_IS_TRACED)) {
 117         sixrd_rx_trace_t *tr = vlib_add_trace(vm, node, p0, sizeof(*tr));
 118         tr->tunnel_id = tunnel_sw_if_index;
 119         tr->length = ip40->length;
 120         tr->src.as_u32 = ip40->src_address.as_u32;
 121         tr->dst.as_u32 = ip40->dst_address.as_u32;
 122       }
 123
 124       error:
 125       if (PREDICT_TRUE(error0 == SIXRD_ERROR_NONE)) {
 126         u32 len = vlib_buffer_length_in_chain (vm, p0);
 127         vlib_increment_combined_counter (im->combined_sw_if_counters
 128                                          + VNET_INTERFACE_COUNTER_RX,
 129                                          thread_index,
 130                                          tunnel_sw_if_index,
 131                                          1 /* packets */ ,
 132                                          len /* bytes */ );
 133
 134         vnet_buffer (p0)->sw_if_index[VLIB_RX] = tunnel_sw_if_index;
 135       } else {
 136         p0->error = error_node->errors[error0];
 137       }
 138       vlib_validate_buffer_enqueue_x1(vm, node, next_index, to_next,
 139                                       n_left_to_next, pi0, next0);
 140     }
 141     vlib_put_next_frame(vm, node, next_index, n_left_to_next);
 142   }
 143   return frame->n_vectors;
 144 }
 145
 146 static char *sixrd_error_strings[] = {
 147 #define _(sym, string) string,
 148     foreach_sixrd_error
 149 #undef _
 150 };
 151
 152 VLIB_REGISTER_NODE(ip4_sixrd_node) = {
 153   .function = ip4_sixrd,
 154   .name = "ip4-sixrd",
 155   .vector_size = sizeof(u32),
 156   .format_trace = format_sixrd_rx_trace,
 157   .n_errors = SIXRD_N_ERROR,
 158   .error_strings = sixrd_error_strings,
 159   .n_next_nodes = IP4_SIXRD_N_NEXT,
 160   .next_nodes =
 161   {
 162     [IP4_SIXRD_NEXT_IP6_LOOKUP] = "ip6-lookup",
 163     [IP4_SIXRD_NEXT_DROP] = "error-drop",
 164   },
 165 };