src/vnet/ipsec/ipsec_if_in.c

   1 /*
   2  * ipsec_if_in.c : IPSec interface input node
   3  *
   4  * Copyright (c) 2015 Cisco and/or its affiliates.
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at:
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <vnet/vnet.h>
  19 #include <vnet/api_errno.h>
  20 #include <vnet/ip/ip.h>
  21
  22 #include <vnet/ipsec/ipsec.h>
  23 #include <vnet/ipsec/esp.h>
  24 #include <vnet/ipsec/ipsec_io.h>
  25
  26 /* Statistics (not really errors) */
  27 #define foreach_ipsec_if_input_error                              \
  28 _(RX, "good packets received")                                    \
  29 _(DISABLED, "ipsec packets received on disabled interface")       \
  30 _(NO_TUNNEL, "no matching tunnel")
  31
  32 static char *ipsec_if_input_error_strings[] = {
  33 #define _(sym,string) string,
  34   foreach_ipsec_if_input_error
  35 #undef _
  36 };
  37
  38 typedef enum
  39 {
  40 #define _(sym,str) IPSEC_IF_INPUT_ERROR_##sym,
  41   foreach_ipsec_if_input_error
  42 #undef _
  43     IPSEC_IF_INPUT_N_ERROR,
  44 } ipsec_if_input_error_t;
  45
  46
  47 typedef struct
  48 {
  49   u32 spi;
  50   u32 seq;
  51 } ipsec_if_input_trace_t;
  52
  53 static u8 *
  54 format_ipsec_if_input_trace (u8 * s, va_list * args)
  55 {
  56   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  57   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  58   ipsec_if_input_trace_t *t = va_arg (*args, ipsec_if_input_trace_t *);
  59
  60   s = format (s, "IPSec: spi %u seq %u", t->spi, t->seq);
  61   return s;
  62 }
  63
  64 VLIB_NODE_FN (ipsec_if_input_node) (vlib_main_t * vm,
  65                                     vlib_node_runtime_t * node,
  66                                     vlib_frame_t * from_frame)
  67 {
  68   ipsec_main_t *im = &ipsec_main;
  69   vnet_main_t *vnm = im->vnet_main;
  70   vnet_interface_main_t *vim = &vnm->interface_main;
  71   u32 *from, *to_next = 0, next_index;
  72   u32 n_left_from, last_sw_if_index = ~0;
  73   u32 thread_index = vm->thread_index;
  74   u64 n_bytes = 0, n_packets = 0;
  75   const ipsec_tunnel_if_t *last_t = NULL;
  76   vlib_combined_counter_main_t *rx_counter;
  77   vlib_combined_counter_main_t *drop_counter;
  78   u32 n_disabled = 0, n_no_tunnel = 0;
  79
  80   rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
  81   drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
  82
  83   from = vlib_frame_vector_args (from_frame);
  84   n_left_from = from_frame->n_vectors;
  85   next_index = node->cached_next_index;
  86
  87   while (n_left_from > 0)
  88     {
  89       u32 n_left_to_next;
  90
  91       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  92
  93       while (n_left_from > 0 && n_left_to_next > 0)
  94         {
  95           u32 bi0, next0, sw_if_index0;
  96           const esp_header_t *esp0;
  97           const ip4_header_t *ip0;
  98           vlib_buffer_t *b0;
  99           uword *p;
 100           u32 len0;
 101
 102           bi0 = to_next[0] = from[0];
 103           from += 1;
 104           n_left_from -= 1;
 105           to_next += 1;
 106           n_left_to_next -= 1;
 107           b0 = vlib_get_buffer (vm, bi0);
 108           ip0 = vlib_buffer_get_current (b0);
 109           esp0 = (const esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 110
 111           next0 = IPSEC_INPUT_NEXT_DROP;
 112
 113           u64 key = (u64) ip0->src_address.as_u32 << 32 | (u64) esp0->spi;
 114
 115           p = hash_get (im->ipsec_if_pool_index_by_key, key);
 116
 117           /* stats for the tunnel include all the data after the IP header
 118              just like a norml IP-IP tunnel */
 119           vlib_buffer_advance (b0, ip4_header_bytes (ip0));
 120           len0 = vlib_buffer_length_in_chain (vm, b0);
 121
 122           if (PREDICT_TRUE (NULL != p))
 123             {
 124               const ipsec_tunnel_if_t *t0;
 125
 126               t0 = pool_elt_at_index (im->tunnel_interfaces, p[0]);
 127               vnet_buffer (b0)->ipsec.sad_index = t0->input_sa_index;
 128
 129               if (PREDICT_TRUE (t0->hw_if_index != ~0))
 130                 {
 131                   vnet_buffer (b0)->ipsec.flags = 0;
 132                   sw_if_index0 = t0->sw_if_index;
 133                   vnet_buffer (b0)->sw_if_index[VLIB_RX] = sw_if_index0;
 134
 135                   if (PREDICT_FALSE
 136                       (!(t0->flags & VNET_HW_INTERFACE_FLAG_LINK_UP)))
 137                     {
 138                       vlib_increment_combined_counter
 139                         (drop_counter, thread_index, sw_if_index0, 1, len0);
 140                       b0->error = node->errors[IPSEC_IF_INPUT_ERROR_DISABLED];
 141                       n_disabled++;
 142                       goto trace;
 143                     }
 144
 145                   if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
 146                     {
 147                       n_packets++;
 148                       n_bytes += len0;
 149                     }
 150                   else
 151                     {
 152                       if (last_t)
 153                         {
 154                           vlib_increment_combined_counter
 155                             (rx_counter, thread_index, sw_if_index0,
 156                              n_packets, n_bytes);
 157                         }
 158
 159                       last_sw_if_index = sw_if_index0;
 160                       last_t = t0;
 161                       n_packets = 1;
 162                       n_bytes = len0;
 163                     }
 164                 }
 165               else
 166                 {
 167                   vnet_buffer (b0)->ipsec.flags = IPSEC_FLAG_IPSEC_GRE_TUNNEL;
 168                 }
 169
 170               next0 = im->esp4_decrypt_next_index;
 171             }
 172           else
 173             {
 174               b0->error = node->errors[IPSEC_IF_INPUT_ERROR_NO_TUNNEL];
 175               n_no_tunnel++;
 176             }
 177
 178         trace:
 179           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 180             {
 181               ipsec_if_input_trace_t *tr =
 182                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 183               tr->spi = clib_host_to_net_u32 (esp0->spi);
 184               tr->seq = clib_host_to_net_u32 (esp0->seq);
 185             }
 186
 187           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 188                                            n_left_to_next, bi0, next0);
 189         }
 190       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 191     }
 192
 193   if (last_t)
 194     {
 195       vlib_increment_combined_counter (rx_counter,
 196                                        thread_index,
 197                                        last_sw_if_index, n_packets, n_bytes);
 198     }
 199
 200   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 201                                IPSEC_IF_INPUT_ERROR_RX,
 202                                from_frame->n_vectors - n_disabled);
 203
 204   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 205                                IPSEC_IF_INPUT_ERROR_DISABLED, n_disabled);
 206   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 207                                IPSEC_IF_INPUT_ERROR_DISABLED, n_no_tunnel);
 208
 209   return from_frame->n_vectors;
 210 }
 211
 212 /* *INDENT-OFF* */
 213 VLIB_REGISTER_NODE (ipsec_if_input_node) = {
 214   .name = "ipsec-if-input",
 215   .vector_size = sizeof (u32),
 216   .format_trace = format_ipsec_if_input_trace,
 217   .type = VLIB_NODE_TYPE_INTERNAL,
 218
 219   .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
 220   .error_strings = ipsec_if_input_error_strings,
 221
 222   .sibling_of = "ipsec4-input-feature",
 223 };
 224 /* *INDENT-ON* */
 225
 226 /*
 227  * fd.io coding-style-patch-verification: ON
 228  *
 229  * Local Variables:
 230  * eval: (c-set-style "gnu")
 231  * End:
 232  */