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
  25 /* Statistics (not really errors) */
  26 #define foreach_ipsec_if_input_error                              \
  27 _(RX, "good packets received")                                    \
  28 _(DISABLED, "ipsec packets received on disabled interface")       \
  29 _(NO_TUNNEL, "no matching tunnel")
  30
  31 static char *ipsec_if_input_error_strings[] = {
  32 #define _(sym,string) string,
  33   foreach_ipsec_if_input_error
  34 #undef _
  35 };
  36
  37 typedef enum
  38 {
  39 #define _(sym,str) IPSEC_IF_INPUT_ERROR_##sym,
  40   foreach_ipsec_if_input_error
  41 #undef _
  42     IPSEC_IF_INPUT_N_ERROR,
  43 } ipsec_if_input_error_t;
  44
  45
  46 typedef struct
  47 {
  48   u32 spi;
  49   u32 seq;
  50 } ipsec_if_input_trace_t;
  51
  52 u8 *
  53 format_ipsec_if_input_trace (u8 * s, va_list * args)
  54 {
  55   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  56   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  57   ipsec_if_input_trace_t *t = va_arg (*args, ipsec_if_input_trace_t *);
  58
  59   s = format (s, "IPSec: spi %u seq %u", t->spi, t->seq);
  60   return s;
  61 }
  62
  63 VLIB_NODE_FN (ipsec_if_input_node) (vlib_main_t * vm,
  64                                     vlib_node_runtime_t * node,
  65                                     vlib_frame_t * from_frame)
  66 {
  67   ipsec_main_t *im = &ipsec_main;
  68   vnet_main_t *vnm = im->vnet_main;
  69   vnet_interface_main_t *vim = &vnm->interface_main;
  70   ipsec_proto_main_t *em = &ipsec_proto_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   u8 icv_len;
  76   ipsec_tunnel_if_t *last_t = NULL;
  77   ipsec_sa_t *sa0;
  78   vlib_combined_counter_main_t *rx_counter;
  79   vlib_combined_counter_main_t *drop_counter;
  80   u32 n_disabled = 0, n_no_tunnel = 0;
  81
  82   rx_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_RX;
  83   drop_counter = vim->combined_sw_if_counters + VNET_INTERFACE_COUNTER_DROP;
  84
  85   from = vlib_frame_vector_args (from_frame);
  86   n_left_from = from_frame->n_vectors;
  87   next_index = node->cached_next_index;
  88
  89   while (n_left_from > 0)
  90     {
  91       u32 n_left_to_next;
  92
  93       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  94
  95       while (n_left_from > 0 && n_left_to_next > 0)
  96         {
  97           u32 bi0, next0, sw_if_index0;
  98           vlib_buffer_t *b0;
  99           ip4_header_t *ip0;
 100           esp_header_t *esp0;
 101           uword *p;
 102           u32 len0;
 103
 104           bi0 = to_next[0] = from[0];
 105           from += 1;
 106           n_left_from -= 1;
 107           to_next += 1;
 108           n_left_to_next -= 1;
 109           b0 = vlib_get_buffer (vm, bi0);
 110           ip0 = vlib_buffer_get_current (b0);
 111           esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 112
 113           next0 = IPSEC_INPUT_NEXT_DROP;
 114
 115           u64 key = (u64) ip0->src_address.as_u32 << 32 |
 116             (u64) clib_net_to_host_u32 (esp0->spi);
 117
 118           p = hash_get (im->ipsec_if_pool_index_by_key, key);
 119
 120           len0 = vlib_buffer_length_in_chain (vm, b0);
 121
 122           if (p)
 123             {
 124               ipsec_tunnel_if_t *t;
 125               t = pool_elt_at_index (im->tunnel_interfaces, p[0]);
 126               vnet_buffer (b0)->ipsec.sad_index = t->input_sa_index;
 127               if (t->hw_if_index != ~0)
 128                 {
 129                   vnet_hw_interface_t *hi;
 130
 131                   vnet_buffer (b0)->ipsec.flags = 0;
 132                   hi = vnet_get_hw_interface (vnm, t->hw_if_index);
 133                   sw_if_index0 = hi->sw_if_index;
 134                   vnet_buffer (b0)->sw_if_index[VLIB_RX] = sw_if_index0;
 135
 136                   if (PREDICT_FALSE
 137                       (!(hi->flags & VNET_HW_INTERFACE_FLAG_LINK_UP)))
 138                     {
 139                       vlib_increment_combined_counter
 140                         (drop_counter, thread_index, sw_if_index0, 1, len0);
 141                       b0->error = node->errors[IPSEC_IF_INPUT_ERROR_DISABLED];
 142                       n_disabled++;
 143                       goto trace;
 144                     }
 145
 146                   if (PREDICT_TRUE (sw_if_index0 == last_sw_if_index))
 147                     {
 148                       n_packets++;
 149                       n_bytes += len0;
 150                     }
 151                   else
 152                     {
 153                       sa0 = pool_elt_at_index (im->sad, t->input_sa_index);
 154                       icv_len =
 155                         em->ipsec_proto_main_integ_algs[sa0->
 156                                                         integ_alg].trunc_size;
 157
 158                       /* length = packet length - ESP/tunnel overhead */
 159                       n_bytes -= n_packets * (sizeof (ip4_header_t) +
 160                                               sizeof (esp_header_t) +
 161                                               sizeof (esp_footer_t) +
 162                                               16 /* aes-cbc IV */  + icv_len);
 163
 164                       if (last_t)
 165                         {
 166                           vlib_increment_combined_counter
 167                             (rx_counter, thread_index, sw_if_index0,
 168                              n_packets, n_bytes);
 169                         }
 170
 171                       last_sw_if_index = sw_if_index0;
 172                       last_t = t;
 173                       n_packets = 1;
 174                       n_bytes = len0;
 175                     }
 176                 }
 177               else
 178                 {
 179                   vnet_buffer (b0)->ipsec.flags = IPSEC_FLAG_IPSEC_GRE_TUNNEL;
 180                 }
 181
 182               vlib_buffer_advance (b0, ip4_header_bytes (ip0));
 183               next0 = im->esp4_decrypt_next_index;
 184             }
 185           else
 186             {
 187               b0->error = node->errors[IPSEC_IF_INPUT_ERROR_NO_TUNNEL];
 188               n_no_tunnel++;
 189             }
 190
 191         trace:
 192           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 193             {
 194               ipsec_if_input_trace_t *tr =
 195                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 196               tr->spi = clib_host_to_net_u32 (esp0->spi);
 197               tr->seq = clib_host_to_net_u32 (esp0->seq);
 198             }
 199
 200           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 201                                            n_left_to_next, bi0, next0);
 202         }
 203       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 204     }
 205
 206   if (last_t)
 207     {
 208       sa0 = pool_elt_at_index (im->sad, last_t->input_sa_index);
 209       icv_len = em->ipsec_proto_main_integ_algs[sa0->integ_alg].trunc_size;
 210
 211       n_bytes -= n_packets * (sizeof (ip4_header_t) + sizeof (esp_header_t) +
 212                               sizeof (esp_footer_t) + 16 /* aes-cbc IV */  +
 213                               icv_len);
 214       vlib_increment_combined_counter (rx_counter,
 215                                        thread_index,
 216                                        last_sw_if_index, n_packets, n_bytes);
 217     }
 218
 219   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 220                                IPSEC_IF_INPUT_ERROR_RX,
 221                                from_frame->n_vectors - n_disabled);
 222
 223   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 224                                IPSEC_IF_INPUT_ERROR_DISABLED, n_disabled);
 225   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 226                                IPSEC_IF_INPUT_ERROR_DISABLED, n_no_tunnel);
 227
 228   return from_frame->n_vectors;
 229 }
 230
 231 /* *INDENT-OFF* */
 232 VLIB_REGISTER_NODE (ipsec_if_input_node) = {
 233   .name = "ipsec-if-input",
 234   .vector_size = sizeof (u32),
 235   .format_trace = format_ipsec_if_input_trace,
 236   .type = VLIB_NODE_TYPE_INTERNAL,
 237
 238   .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
 239   .error_strings = ipsec_if_input_error_strings,
 240
 241   .sibling_of = "ipsec4-input-feature",
 242 };
 243 /* *INDENT-ON* */
 244
 245 /*
 246  * fd.io coding-style-patch-verification: ON
 247  *
 248  * Local Variables:
 249  * eval: (c-set-style "gnu")
 250  * End:
 251  */