vnet/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
  29 static char *ipsec_if_input_error_strings[] = {
  30 #define _(sym,string) string,
  31   foreach_ipsec_if_input_error
  32 #undef _
  33 };
  34
  35 typedef enum
  36 {
  37 #define _(sym,str) IPSEC_IF_INPUT_ERROR_##sym,
  38   foreach_ipsec_if_input_error
  39 #undef _
  40     IPSEC_IF_INPUT_N_ERROR,
  41 } ipsec_if_input_error_t;
  42
  43 typedef enum
  44 {
  45   IPSEC_IF_INPUT_NEXT_ESP_DECRYPT,
  46   IPSEC_IF_INPUT_NEXT_DROP,
  47   IPSEC_IF_INPUT_N_NEXT,
  48 } ipsec_if_input_next_t;
  49
  50 typedef struct
  51 {
  52   u32 spi;
  53   u32 seq;
  54 } ipsec_if_input_trace_t;
  55
  56
  57 u8 *
  58 format_ipsec_if_input_trace (u8 * s, va_list * args)
  59 {
  60   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  61   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  62   ipsec_if_input_trace_t *t = va_arg (*args, ipsec_if_input_trace_t *);
  63
  64   s = format (s, "IPSec: spi %u seq %u", t->spi, t->seq);
  65   return s;
  66 }
  67
  68 static uword
  69 ipsec_if_input_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
  70                         vlib_frame_t * from_frame)
  71 {
  72   ipsec_main_t *im = &ipsec_main;
  73   u32 *from, *to_next = 0, next_index;
  74   u32 n_left_from;
  75
  76   from = vlib_frame_vector_args (from_frame);
  77   n_left_from = from_frame->n_vectors;
  78   next_index = node->cached_next_index;
  79
  80   while (n_left_from > 0)
  81     {
  82       u32 n_left_to_next;
  83
  84       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  85
  86       while (n_left_from > 0 && n_left_to_next > 0)
  87         {
  88           u32 bi0, next0;
  89           vlib_buffer_t *b0;
  90           ip4_header_t *ip0;
  91           esp_header_t *esp0;
  92           uword *p;
  93
  94           bi0 = to_next[0] = from[0];
  95           from += 1;
  96           n_left_from -= 1;
  97           to_next += 1;
  98           n_left_to_next -= 1;
  99           b0 = vlib_get_buffer (vm, bi0);
 100           ip0 = vlib_buffer_get_current (b0);
 101           esp0 = (esp_header_t *) ((u8 *) ip0 + ip4_header_bytes (ip0));
 102
 103           next0 = IPSEC_IF_INPUT_NEXT_DROP;
 104
 105           u64 key = (u64) ip0->src_address.as_u32 << 32 |
 106             (u64) clib_net_to_host_u32 (esp0->spi);
 107
 108           p = hash_get (im->ipsec_if_pool_index_by_key, key);
 109
 110           if (p)
 111             {
 112               ipsec_tunnel_if_t *t;
 113               t = pool_elt_at_index (im->tunnel_interfaces, p[0]);
 114               vnet_buffer (b0)->output_features.ipsec_sad_index =
 115                 t->input_sa_index;
 116               vlib_buffer_advance (b0, ip4_header_bytes (ip0));
 117               next0 = IPSEC_IF_INPUT_NEXT_ESP_DECRYPT;
 118             }
 119
 120           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 121             {
 122               ipsec_if_input_trace_t *tr =
 123                 vlib_add_trace (vm, node, b0, sizeof (*tr));
 124               tr->spi = clib_host_to_net_u32 (esp0->spi);
 125               tr->seq = clib_host_to_net_u32 (esp0->seq);
 126             }
 127
 128           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 129                                            n_left_to_next, bi0, next0);
 130         }
 131       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 132     }
 133
 134   vlib_node_increment_counter (vm, ipsec_if_input_node.index,
 135                                IPSEC_IF_INPUT_ERROR_RX,
 136                                from_frame->n_vectors);
 137
 138   return from_frame->n_vectors;
 139 }
 140
 141 /* *INDENT-OFF* */
 142 VLIB_REGISTER_NODE (ipsec_if_input_node) = {
 143   .function = ipsec_if_input_node_fn,
 144   .name = "ipsec-if-input",
 145   .vector_size = sizeof (u32),
 146   .format_trace = format_ipsec_if_input_trace,
 147   .type = VLIB_NODE_TYPE_INTERNAL,
 148
 149   .n_errors = ARRAY_LEN(ipsec_if_input_error_strings),
 150   .error_strings = ipsec_if_input_error_strings,
 151
 152   .n_next_nodes = IPSEC_IF_INPUT_N_NEXT,
 153
 154   .next_nodes = {
 155         [IPSEC_IF_INPUT_NEXT_ESP_DECRYPT] = "esp-decrypt",
 156         [IPSEC_IF_INPUT_NEXT_DROP] = "error-drop",
 157   },
 158 };
 159 /* *INDENT-ON* */
 160
 161 VLIB_NODE_FUNCTION_MULTIARCH (ipsec_if_input_node, ipsec_if_input_node_fn)
 162 /*
 163  * fd.io coding-style-patch-verification: ON
 164  *
 165  * Local Variables:
 166  * eval: (c-set-style "gnu")
 167  * End:
 168  */