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