src/plugins/nat/dslite/dslite_ce_encap.c

   1 /*
   2  * Copyright (c) 2018 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 #include <nat/dslite/dslite.h>
  16 #include <nat/nat_inlines.h>
  17
  18 typedef enum
  19 {
  20   DSLITE_CE_ENCAP_NEXT_IP6_LOOKUP,
  21   DSLITE_CE_ENCAP_NEXT_DROP,
  22   DSLITE_CE_ENCAP_N_NEXT,
  23 } dslite_ce_encap_next_t;
  24
  25 static char *dslite_ce_encap_error_strings[] = {
  26 #define _(sym,string) string,
  27   foreach_dslite_error
  28 #undef _
  29 };
  30
  31 VLIB_NODE_FN (dslite_ce_encap_node) (vlib_main_t * vm,
  32                                      vlib_node_runtime_t * node,
  33                                      vlib_frame_t * frame)
  34 {
  35   u32 n_left_from, *from, *to_next;
  36   dslite_ce_encap_next_t next_index;
  37   dslite_main_t *dm = &dslite_main;
  38
  39   from = vlib_frame_vector_args (frame);
  40   n_left_from = frame->n_vectors;
  41   next_index = node->cached_next_index;
  42
  43   while (n_left_from > 0)
  44     {
  45       u32 n_left_to_next;
  46
  47       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
  48
  49       while (n_left_from > 0 && n_left_to_next > 0)
  50         {
  51           u32 bi0;
  52           vlib_buffer_t *b0;
  53           u32 next0 = DSLITE_CE_ENCAP_NEXT_IP6_LOOKUP;
  54           u8 error0 = DSLITE_ERROR_CE_ENCAP;
  55           ip4_header_t *ip40;
  56           ip6_header_t *ip60;
  57           u32 proto0;
  58
  59           /* speculatively enqueue b0 to the current next frame */
  60           bi0 = from[0];
  61           to_next[0] = bi0;
  62           from += 1;
  63           to_next += 1;
  64           n_left_from -= 1;
  65           n_left_to_next -= 1;
  66
  67           b0 = vlib_get_buffer (vm, bi0);
  68           ip40 = vlib_buffer_get_current (b0);
  69           proto0 = ip_proto_to_snat_proto (ip40->protocol);
  70
  71           if (PREDICT_FALSE (proto0 == ~0))
  72             {
  73               error0 = DSLITE_ERROR_UNSUPPORTED_PROTOCOL;
  74               next0 = DSLITE_CE_ENCAP_NEXT_DROP;
  75               goto trace0;
  76             }
  77
  78           /* Construct IPv6 header */
  79           vlib_buffer_advance (b0, -(sizeof (ip6_header_t)));
  80           ip60 = vlib_buffer_get_current (b0);
  81           ip60->ip_version_traffic_class_and_flow_label =
  82             clib_host_to_net_u32 ((6 << 28) + (ip40->tos << 20));
  83           ip60->payload_length = ip40->length;
  84           ip60->protocol = IP_PROTOCOL_IP_IN_IP;
  85           ip60->hop_limit = ip40->ttl;
  86           ip60->dst_address.as_u64[0] = dm->aftr_ip6_addr.as_u64[0];
  87           ip60->dst_address.as_u64[1] = dm->aftr_ip6_addr.as_u64[1];
  88           ip60->src_address.as_u64[0] = dm->b4_ip6_addr.as_u64[0];
  89           ip60->src_address.as_u64[1] = dm->b4_ip6_addr.as_u64[1];
  90
  91         trace0:
  92           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
  93                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
  94             {
  95               dslite_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
  96               t->next_index = next0;
  97             }
  98
  99           b0->error = node->errors[error0];
 100
 101           /* verify speculative enqueue, maybe switch current next frame */
 102           vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 103                                            n_left_to_next, bi0, next0);
 104         }
 105       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 106     }
 107
 108   return frame->n_vectors;
 109 }
 110
 111 /* *INDENT-OFF* */
 112 VLIB_REGISTER_NODE (dslite_ce_encap_node) = {
 113   .name = "dslite-ce-encap",
 114   .vector_size = sizeof (u32),
 115   .format_trace = format_dslite_ce_trace,
 116   .type = VLIB_NODE_TYPE_INTERNAL,
 117   .n_errors = ARRAY_LEN (dslite_ce_encap_error_strings),
 118   .error_strings = dslite_ce_encap_error_strings,
 119   .n_next_nodes = DSLITE_CE_ENCAP_N_NEXT,
 120   /* edit / add dispositions here */
 121   .next_nodes = {
 122     [DSLITE_CE_ENCAP_NEXT_DROP] = "error-drop",
 123     [DSLITE_CE_ENCAP_NEXT_IP6_LOOKUP] = "ip6-lookup",
 124   },
 125 };
 126 /* *INDENT-ON* */
 127
 128 /*
 129  * fd.io coding-style-patch-verification: ON
 130  *
 131  * Local Variables:
 132  * eval: (c-set-style "gnu")
 133  * End:
 134  */