vnet/vnet/dhcp/proxy_node.c

   1 /*
   2  * proxy_node.c: dhcp proxy node processing
   3  *
   4  * Copyright (c) 2013 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 <vlib/vlib.h>
  19 #include <vnet/pg/pg.h>
  20 #include <vnet/dhcp/proxy.h>
  21 #include <vnet/fib/ip4_fib.h>
  22
  23 static char * dhcp_proxy_error_strings[] = {
  24 #define dhcp_proxy_error(n,s) s,
  25 #include "proxy_error.def"
  26 #undef dhcp_proxy_error
  27 };
  28
  29 #define foreach_dhcp_proxy_to_server_input_next \
  30   _ (DROP, "error-drop")                        \
  31   _ (LOOKUP, "ip4-lookup")                      \
  32   _ (SEND_TO_CLIENT, "dhcp-proxy-to-client")
  33
  34 typedef enum {
  35 #define _(s,n) DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s,
  36   foreach_dhcp_proxy_to_server_input_next
  37 #undef _
  38   DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
  39 } dhcp_proxy_to_server_input_next_t;
  40
  41 typedef struct {
  42   /* 0 => to server, 1 => to client */
  43   int which;
  44   ip4_address_t trace_ip4_address;
  45   u32 error;
  46   u32 sw_if_index;
  47   u32 original_sw_if_index;
  48 } dhcp_proxy_trace_t;
  49
  50 #define VPP_DHCP_OPTION82_SUB1_SIZE   6
  51 #define VPP_DHCP_OPTION82_SUB5_SIZE   6
  52 #define VPP_DHCP_OPTION82_VSS_SIZE    12
  53 #define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
  54                                 VPP_DHCP_OPTION82_SUB5_SIZE + \
  55                                 VPP_DHCP_OPTION82_VSS_SIZE +3)
  56
  57 vlib_node_registration_t dhcp_proxy_to_server_node;
  58 vlib_node_registration_t dhcp_proxy_to_client_node;
  59
  60 u8 * format_dhcp_proxy_trace (u8 * s, va_list * args)
  61 {
  62   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  63   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  64   dhcp_proxy_trace_t * t = va_arg (*args, dhcp_proxy_trace_t *);
  65
  66   if (t->which == 0)
  67     s = format (s, "DHCP proxy: sent to server %U\n",
  68                 format_ip4_address, &t->trace_ip4_address, t->error);
  69   else
  70     s = format (s, "DHCP proxy: broadcast to client from %U\n",
  71                 format_ip4_address, &t->trace_ip4_address);
  72
  73   if (t->error != (u32)~0)
  74     s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
  75
  76   s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
  77               t->original_sw_if_index, t->sw_if_index);
  78
  79   return s;
  80 }
  81
  82 u8 * format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
  83 {
  84   dhcp_header_t * h = va_arg (*args, dhcp_header_t *);
  85   u32 max_header_bytes = va_arg (*args, u32);
  86   u32 header_bytes;
  87
  88   header_bytes = sizeof (h[0]);
  89   if (max_header_bytes != 0 && header_bytes > max_header_bytes)
  90     return format (s, "dhcp header truncated");
  91
  92   s = format (s, "DHCP Proxy");
  93
  94   return s;
  95 }
  96
  97 static uword
  98 dhcp_proxy_to_server_input (vlib_main_t * vm,
  99                             vlib_node_runtime_t * node,
 100                             vlib_frame_t * from_frame)
 101 {
 102   u32 n_left_from, next_index, * from, * to_next;
 103   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 104   from = vlib_frame_vector_args (from_frame);
 105   n_left_from = from_frame->n_vectors;
 106   u32 pkts_to_server=0, pkts_to_client=0, pkts_no_server=0;
 107   u32 pkts_no_interface_address=0;
 108   u32 pkts_too_big=0;
 109   ip4_main_t * im = &ip4_main;
 110
 111   next_index = node->cached_next_index;
 112
 113   while (n_left_from > 0)
 114     {
 115       u32 n_left_to_next;
 116
 117       vlib_get_next_frame (vm, node, next_index,
 118                            to_next, n_left_to_next);
 119
 120       while (n_left_from > 0 && n_left_to_next > 0)
 121         {
 122           u32 bi0;
 123           vlib_buffer_t * b0;
 124           udp_header_t * u0;
 125           dhcp_header_t * h0;
 126           ip4_header_t * ip0;
 127           u32 next0;
 128           u32 old0, new0;
 129           ip_csum_t sum0;
 130           u32 error0 = (u32) ~0;
 131           u32 sw_if_index = 0;
 132           u32 original_sw_if_index = 0;
 133           u8  *end = NULL;
 134           u32 fib_index, server_index;
 135           dhcp_server_t * server;
 136           u32 rx_sw_if_index;
 137
 138           bi0 = from[0];
 139           to_next[0] = bi0;
 140           from += 1;
 141           to_next += 1;
 142           n_left_from -= 1;
 143           n_left_to_next -= 1;
 144
 145           b0 = vlib_get_buffer (vm, bi0);
 146
 147           h0 = vlib_buffer_get_current (b0);
 148
 149           /*
 150            * udp_local hands us the DHCP header, need udp hdr,
 151            * ip hdr to relay to server
 152            */
 153           vlib_buffer_advance (b0, -(sizeof(*u0)));
 154           u0 = vlib_buffer_get_current (b0);
 155
 156           /* This blows. Return traffic has src_port = 67, dst_port = 67 */
 157           if (u0->src_port == clib_net_to_host_u16(UDP_DST_PORT_dhcp_to_server))
 158             {
 159               vlib_buffer_advance (b0, sizeof(*u0));
 160               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
 161               error0 = 0;
 162               pkts_to_client++;
 163               goto do_enqueue;
 164             }
 165
 166           rx_sw_if_index = vnet_buffer(b0)->sw_if_index[VLIB_RX];
 167
 168           fib_index = im->fib_index_by_sw_if_index [rx_sw_if_index];
 169
 170           if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 171             server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
 172           else
 173             server_index = 0;
 174
 175           if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers,
 176                                                  server_index)))
 177             {
 178             no_server:
 179               error0 = DHCP_PROXY_ERROR_NO_SERVER;
 180               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 181               pkts_no_server++;
 182               goto do_trace;
 183             }
 184
 185           server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 186           if (server->valid == 0)
 187             goto no_server;
 188
 189           vlib_buffer_advance (b0, -(sizeof(*ip0)));
 190           ip0 = vlib_buffer_get_current (b0);
 191
 192           /* disable UDP checksum */
 193           u0->checksum = 0;
 194           sum0 = ip0->checksum;
 195           old0 = ip0->dst_address.as_u32;
 196           new0 = server->dhcp_server.as_u32;
 197           ip0->dst_address.as_u32 = server->dhcp_server.as_u32;
 198           sum0 = ip_csum_update (sum0, old0, new0,
 199                                 ip4_header_t /* structure */,
 200                                 dst_address /* changed member */);
 201           ip0->checksum = ip_csum_fold (sum0);
 202
 203           sum0 = ip0->checksum;
 204           old0 = ip0->src_address.as_u32;
 205           new0 = server->dhcp_src_address.as_u32;
 206           ip0->src_address.as_u32 = new0;
 207           sum0 = ip_csum_update (sum0, old0, new0,
 208                                 ip4_header_t /* structure */,
 209                                 src_address /* changed member */);
 210           ip0->checksum = ip_csum_fold (sum0);
 211
 212           /* Send to DHCP server via the configured FIB */
 213           vnet_buffer(b0)->sw_if_index[VLIB_TX] =
 214             server->server_fib_index;
 215
 216           h0->gateway_ip_address.as_u32 = server->dhcp_src_address.as_u32;
 217           pkts_to_server++;
 218
 219           if (server->insert_option_82)
 220             {
 221               u32 fib_index, fib_id, opt82_fib_id=0, opt82_oui=0;
 222               ip4_fib_t * fib;
 223               dhcp_option_t *o = (dhcp_option_t *) h0->options;
 224               u32 len = 0;
 225               vlib_buffer_free_list_t *fl;
 226
 227               fib_index = im->fib_index_by_sw_if_index
 228                 [vnet_buffer(b0)->sw_if_index[VLIB_RX]];
 229               fib = ip4_fib_get (fib_index);
 230               fib_id = fib->table_id;
 231
 232               end = b0->data + b0->current_data + b0->current_length;
 233               /* TLVs are not performance-friendly... */
 234               while  (o->option != 0xFF /* end of options */ && (u8 *)o < end)
 235                   o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 236
 237               fl = vlib_buffer_get_free_list (vm, b0->free_list_index);
 238               // start write at (option*)o, some packets have padding
 239               if (((u8 *)o - (u8 *)b0->data + VPP_DHCP_OPTION82_SIZE) > fl->n_data_bytes)
 240                 {
 241                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 242                   pkts_too_big++;
 243                   goto do_trace;
 244                 }
 245
 246               if ((o->option == 0xFF)  && ((u8 *)o <= end))
 247                 {
 248                   vnet_main_t *vnm = vnet_get_main();
 249                   u16 old_l0, new_l0;
 250                   ip4_address_t _ia0, * ia0 = &_ia0;
 251                   uword  *p_vss;
 252                   vss_info *vss;
 253                   vnet_sw_interface_t *swif;
 254                   sw_if_index = 0;
 255                   original_sw_if_index = 0;
 256
 257                   original_sw_if_index = sw_if_index =
 258                       vnet_buffer(b0)->sw_if_index[VLIB_RX];
 259                   swif = vnet_get_sw_interface (vnm, sw_if_index);
 260                   if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 261                       sw_if_index = swif->unnumbered_sw_if_index;
 262
 263                   p_vss = hash_get (dpm->opt82vss_index_by_vrf_id,
 264                                     fib_id);
 265                   if (p_vss)
 266                     {
 267                       vss = pool_elt_at_index (dpm->opt82vss, p_vss[0]);
 268                       opt82_oui =  vss->vpn_id.oui;
 269                       opt82_fib_id =  vss->vpn_id.fib_id;
 270                     }
 271                   /*
 272                    * Get the first ip4 address on the [client-side]
 273                    * RX interface, if not unnumbered. otherwise use
 274                    * the loopback interface's ip address.
 275                    */
 276                   ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
 277
 278                   if (ia0 == 0)
 279                     {
 280                       error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 281                       next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 282                       pkts_no_interface_address++;
 283                       goto do_trace;
 284                     }
 285
 286                   /* Add option 82 */
 287                   o->option = 82;   /* option 82 */
 288                   o->length = 12;   /* 12 octets to follow */
 289                   o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
 290                   o->data[1] = 4;   /* length of suboption */
 291                   o->data[2] = (original_sw_if_index >> 24) & 0xFF;
 292                   o->data[3] = (original_sw_if_index >> 16) & 0xFF;
 293                   o->data[4] = (original_sw_if_index >> 8)  & 0xFF;
 294                   o->data[5] = (original_sw_if_index >> 0)  & 0xFF;
 295                   o->data[6] = 5; /* suboption 5 (client RX intfc address) */
 296                   o->data[7] = 4; /* length 4 */
 297                   o->data[8] = ia0->as_u8[0];
 298                   o->data[9] = ia0->as_u8[1];
 299                   o->data[10] = ia0->as_u8[2];
 300                   o->data[11] = ia0->as_u8[3];
 301                   o->data[12] = 0xFF;
 302                   if (opt82_oui !=0 || opt82_fib_id != 0)
 303                     {
 304                       o->data[12] = 151; /* vss suboption */
 305                       if (255 == opt82_fib_id) {
 306                           o->data[13] = 1;   /* length */
 307                           o->data[14] = 255;   /* vss option type */
 308                           o->data[15] = 152; /* vss control suboption */
 309                           o->data[16] = 0;   /* length */
 310                           /* and a new "end-of-options" option (0xff) */
 311                           o->data[17] = 0xFF;
 312                           o->length += 5;
 313                       } else {
 314                           o->data[13] = 8;   /* length */
 315                           o->data[14] = 1;   /* vss option type */
 316                           o->data[15] = (opt82_oui >> 16) & 0xff;
 317                           o->data[16] = (opt82_oui >> 8) & 0xff;
 318                           o->data[17] = (opt82_oui ) & 0xff;
 319                           o->data[18] = (opt82_fib_id >> 24) & 0xff;
 320                           o->data[19] = (opt82_fib_id >> 16) & 0xff;
 321                           o->data[20] = (opt82_fib_id >> 8) & 0xff;
 322                           o->data[21] = (opt82_fib_id) & 0xff;
 323                           o->data[22] = 152; /* vss control suboption */
 324                           o->data[23] = 0;   /* length */
 325
 326                           /* and a new "end-of-options" option (0xff) */
 327                           o->data[24] = 0xFF;
 328                           o->length += 12;
 329                       }
 330                   }
 331
 332                   len = o->length + 3;
 333                   b0->current_length += len;
 334                   /* Fix IP header length and checksum */
 335                   old_l0 = ip0->length;
 336                   new_l0 = clib_net_to_host_u16 (old_l0);
 337                   new_l0 += len;
 338                   new_l0 = clib_host_to_net_u16 (new_l0);
 339                   ip0->length = new_l0;
 340                   sum0 = ip0->checksum;
 341                   sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 342                                          length /* changed member */);
 343                   ip0->checksum = ip_csum_fold (sum0);
 344
 345                   /* Fix UDP length */
 346                   new_l0 = clib_net_to_host_u16 (u0->length);
 347                   new_l0 += len;
 348                   u0->length = clib_host_to_net_u16 (new_l0);
 349                 } else {
 350                   vlib_node_increment_counter
 351                       (vm, dhcp_proxy_to_server_node.index,
 352                        DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
 353                 }
 354             }
 355
 356           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
 357
 358         do_trace:
 359           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 360             {
 361                dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 362                                                         b0, sizeof (*tr));
 363                tr->which = 0; /* to server */
 364                tr->error = error0;
 365                tr->original_sw_if_index = original_sw_if_index;
 366                tr->sw_if_index = sw_if_index;
 367                if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 368                  tr->trace_ip4_address.as_u32 = server->dhcp_server.as_u32;
 369             }
 370
 371         do_enqueue:
 372           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 373                                            to_next, n_left_to_next,
 374                                            bi0, next0);
 375         }
 376
 377       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 378     }
 379
 380   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 381                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
 382                                pkts_to_client);
 383   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 384                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
 385                                pkts_to_server);
 386   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 387                                DHCP_PROXY_ERROR_NO_SERVER,
 388                                pkts_no_server);
 389   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 390                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
 391                                pkts_no_interface_address);
 392  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 393                               DHCP_PROXY_ERROR_PKT_TOO_BIG,
 394                               pkts_too_big);
 395   return from_frame->n_vectors;
 396 }
 397
 398 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node) = {
 399   .function = dhcp_proxy_to_server_input,
 400   .name = "dhcp-proxy-to-server",
 401   /* Takes a vector of packets. */
 402   .vector_size = sizeof (u32),
 403
 404   .n_errors = DHCP_PROXY_N_ERROR,
 405   .error_strings = dhcp_proxy_error_strings,
 406
 407   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
 408   .next_nodes = {
 409 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
 410     foreach_dhcp_proxy_to_server_input_next
 411 #undef _
 412   },
 413
 414   .format_buffer = format_dhcp_proxy_header_with_length,
 415   .format_trace = format_dhcp_proxy_trace,
 416 #if 0
 417   .unformat_buffer = unformat_dhcp_proxy_header,
 418 #endif
 419 };
 420
 421 static uword
 422 dhcp_proxy_to_client_input (vlib_main_t * vm,
 423                             vlib_node_runtime_t * node,
 424                             vlib_frame_t * from_frame)
 425 {
 426   u32 n_left_from, * from;
 427   ethernet_main_t *em = ethernet_get_main (vm);
 428   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 429   vnet_main_t * vnm = vnet_get_main();
 430   ip4_main_t * im = &ip4_main;
 431
 432   from = vlib_frame_vector_args (from_frame);
 433   n_left_from = from_frame->n_vectors;
 434
 435   while (n_left_from > 0)
 436     {
 437       u32 bi0;
 438       vlib_buffer_t * b0;
 439       udp_header_t * u0;
 440       dhcp_header_t * h0;
 441       ip4_header_t * ip0 = 0;
 442       ip4_address_t * ia0 = 0;
 443       u32 old0, new0;
 444       ip_csum_t sum0;
 445       ethernet_interface_t *ei0;
 446       ethernet_header_t *mac0;
 447       vnet_hw_interface_t *hi0;
 448       vlib_frame_t *f0;
 449       u32 * to_next0;
 450       u32 sw_if_index = ~0;
 451       vnet_sw_interface_t *si0;
 452       u32 error0 = (u32)~0;
 453       vnet_sw_interface_t *swif;
 454       u32 server_index;
 455       u32 fib_index;
 456       dhcp_server_t * server;
 457       u32 original_sw_if_index = (u32) ~0;
 458
 459       bi0 = from[0];
 460       from += 1;
 461       n_left_from -= 1;
 462
 463       b0 = vlib_get_buffer (vm, bi0);
 464       h0 = vlib_buffer_get_current (b0);
 465
 466       /*
 467        * udp_local hands us the DHCP header, need udp hdr,
 468        * ip hdr to relay to client
 469        */
 470       vlib_buffer_advance (b0, -(sizeof(*u0)));
 471       u0 = vlib_buffer_get_current (b0);
 472
 473       vlib_buffer_advance (b0, -(sizeof(*ip0)));
 474       ip0 = vlib_buffer_get_current (b0);
 475
 476       /* Consumed by dhcp client code? */
 477       if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
 478           continue;
 479
 480       if (1 /* dpm->insert_option_82 */)
 481         {
 482           dhcp_option_t *o = (dhcp_option_t *) h0->options;
 483           dhcp_option_t *sub;
 484
 485           /* Parse through TLVs looking for option 82.
 486              The circuit-ID is the FIB number we need
 487              to track down the client-facing interface */
 488
 489           while (o->option != 0xFF /* end of options */ &&
 490                  (u8 *) o < (b0->data + b0->current_data + b0->current_length))
 491             {
 492               if (o->option == 82)
 493                 {
 494                     u32 vss_exist = 0;
 495                     u32 vss_ctrl = 0;
 496                     sub = (dhcp_option_t *) &o->data[0];
 497                     while (sub->option != 0xFF /* end of options */ &&
 498                            (u8 *) sub < (u8 *)(o + o->length)) {
 499                         /* If this is one of ours, it will have
 500                            total length 12, circuit-id suboption type,
 501                            and the sw_if_index */
 502                         if (sub->option == 1 && sub->length == 4)
 503                           {
 504                             sw_if_index = (o->data[2] << 24)
 505                                 | (o->data[3] << 16)
 506                                 | (o->data[4] << 8)
 507                                 | (o->data[5]);
 508                           } else if (sub->option == 151 &&
 509                                      sub->length == 7 &&
 510                                      sub->data[0] == 1)
 511                             vss_exist = 1;
 512                         else if (sub->option == 152 && sub->length == 0)
 513                             vss_ctrl = 1;
 514                         sub = (dhcp_option_t *)
 515                           (((uword) sub) + (sub->length + 2));
 516                     }
 517                     if (vss_ctrl && vss_exist)
 518                       vlib_node_increment_counter
 519                         (vm, dhcp_proxy_to_client_node.index,
 520                          DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 521
 522                 }
 523               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 524             }
 525         }
 526
 527       if (sw_if_index == (u32)~0)
 528         {
 529           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 530
 531         drop_packet:
 532           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 533                                        error0, 1);
 534           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 535           to_next0 = vlib_frame_vector_args (f0);
 536           to_next0[0] = bi0;
 537           f0->n_vectors = 1;
 538           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 539           goto do_trace;
 540         }
 541
 542
 543       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 544         {
 545           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
 546           goto drop_packet;
 547         }
 548
 549       fib_index = im->fib_index_by_sw_if_index [sw_if_index];
 550
 551       if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 552         server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
 553       else
 554         server_index = 0;
 555
 556       if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers,
 557                                              server_index)))
 558         {
 559           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
 560           goto drop_packet;
 561         }
 562
 563       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 564       if (server->valid == 0)
 565         {
 566           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 567           goto drop_packet;
 568         }
 569
 570       if (ip0->src_address.as_u32 != server->dhcp_server.as_u32)
 571         {
 572           error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 573           goto drop_packet;
 574         }
 575
 576       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 577
 578       swif = vnet_get_sw_interface (vnm, sw_if_index);
 579       original_sw_if_index = sw_if_index;
 580       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 581           sw_if_index = swif->unnumbered_sw_if_index;
 582
 583       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 584       if (ia0 == 0)
 585         {
 586           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 587           goto drop_packet;
 588         }
 589
 590       u0->checksum = 0;
 591       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 592       sum0 = ip0->checksum;
 593       old0 = ip0->dst_address.as_u32;
 594       new0 = 0xFFFFFFFF;
 595       ip0->dst_address.as_u32 = new0;
 596       sum0 = ip_csum_update (sum0, old0, new0,
 597                             ip4_header_t /* structure */,
 598                             dst_address /* offset of changed member */);
 599       ip0->checksum = ip_csum_fold (sum0);
 600
 601       sum0 = ip0->checksum;
 602       old0 = ip0->src_address.as_u32;
 603       new0 = ia0->as_u32;
 604       ip0->src_address.as_u32 = new0;
 605       sum0 = ip_csum_update (sum0, old0, new0,
 606                             ip4_header_t /* structure */,
 607                             src_address /* offset of changed member */);
 608       ip0->checksum = ip_csum_fold (sum0);
 609
 610       vlib_buffer_advance (b0, -(sizeof(ethernet_header_t)));
 611       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 612       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 613           vlib_buffer_advance (b0, -4 /* space for VLAN tag */);
 614
 615       mac0 = vlib_buffer_get_current (b0);
 616
 617       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 618       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 619       clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 620       memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 621       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 622         clib_net_to_host_u16(0x8100) : clib_net_to_host_u16 (0x0800);
 623
 624       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 625         {
 626           u32 * vlan_tag = (u32 *)(mac0+1);
 627           u32 tmp;
 628           tmp = (si0->sub.id << 16) | 0x0800;
 629           *vlan_tag = clib_host_to_net_u32 (tmp);
 630         }
 631
 632       /* $$$ This needs to be rewritten, for sure */
 633       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 634       to_next0 = vlib_frame_vector_args (f0);
 635       to_next0[0] = bi0;
 636       f0->n_vectors = 1;
 637       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 638
 639     do_trace:
 640       if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 641         {
 642           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 643                                                    b0, sizeof (*tr));
 644           tr->which = 1; /* to client */
 645           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 646           tr->error = error0;
 647           tr->original_sw_if_index = original_sw_if_index;
 648           tr->sw_if_index = sw_if_index;
 649         }
 650     }
 651   return from_frame->n_vectors;
 652 }
 653
 654 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node) = {
 655   .function = dhcp_proxy_to_client_input,
 656   .name = "dhcp-proxy-to-client",
 657   /* Takes a vector of packets. */
 658   .vector_size = sizeof (u32),
 659
 660   .n_errors = DHCP_PROXY_N_ERROR,
 661   .error_strings = dhcp_proxy_error_strings,
 662   .format_buffer = format_dhcp_proxy_header_with_length,
 663   .format_trace = format_dhcp_proxy_trace,
 664 #if 0
 665   .unformat_buffer = unformat_dhcp_proxy_header,
 666 #endif
 667 };
 668
 669 clib_error_t * dhcp_proxy_init (vlib_main_t * vm)
 670 {
 671   dhcp_proxy_main_t * dm = &dhcp_proxy_main;
 672   vlib_node_t * error_drop_node;
 673   dhcp_server_t * server;
 674
 675   dm->vlib_main = vm;
 676   dm->vnet_main = vnet_get_main();
 677   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 678   dm->error_drop_node_index = error_drop_node->index;
 679
 680   dm->opt82vss_index_by_vrf_id = hash_create (0, sizeof (uword));
 681
 682   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
 683                          dhcp_proxy_to_client_node.index, 1 /* is_ip4 */);
 684
 685   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
 686                          dhcp_proxy_to_server_node.index, 1 /* is_ip4 */);
 687
 688   /* Create the default server, don't mark it valid */
 689   pool_get (dm->dhcp_servers, server);
 690   memset (server, 0, sizeof (*server));
 691
 692   return 0;
 693 }
 694
 695 VLIB_INIT_FUNCTION (dhcp_proxy_init);
 696
 697 int dhcp_proxy_set_server_2 (ip4_address_t *addr, ip4_address_t *src_address,
 698                              u32 rx_fib_id,
 699                              u32 server_fib_id,
 700                              int insert_option_82, int is_del)
 701 {
 702   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 703   dhcp_server_t * server = 0;
 704   u32 server_index = 0;
 705   u32 rx_fib_index = 0;
 706
 707   if (addr->as_u32 == 0)
 708     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 709
 710   if (src_address->as_u32 == 0)
 711     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 712
 713   rx_fib_index = fib_table_find_or_create_and_lock(FIB_PROTOCOL_IP4,
 714                                                    rx_fib_id);
 715
 716   if (rx_fib_id == 0)
 717     {
 718       server = pool_elt_at_index (dpm->dhcp_servers, 0);
 719
 720       if (is_del)
 721         {
 722           memset (server, 0, sizeof (*server));
 723           return 0;
 724         }
 725       goto initialize_it;
 726     }
 727
 728   if (is_del)
 729     {
 730       if (rx_fib_index >= vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 731         return VNET_API_ERROR_NO_SUCH_ENTRY;
 732
 733       server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
 734       ASSERT(server_index > 0);
 735
 736       /* Use the default server again.  */
 737       dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] = 0;
 738       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 739       memset (server, 0, sizeof (*server));
 740       pool_put (dpm->dhcp_servers, server);
 741       return 0;
 742     }
 743
 744   if (rx_fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 745     {
 746       server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
 747       if (server_index != 0)
 748         {
 749           server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 750           goto initialize_it;
 751         }
 752     }
 753
 754   pool_get (dpm->dhcp_servers, server);
 755
 756  initialize_it:
 757
 758   server->dhcp_server.as_u32 = addr->as_u32;
 759   server->server_fib_index =
 760       fib_table_find_or_create_and_lock(FIB_PROTOCOL_IP4,
 761                                         server_fib_id);
 762   server->dhcp_src_address.as_u32 = src_address->as_u32;
 763   server->insert_option_82 = insert_option_82;
 764   server->valid = 1;
 765   if (rx_fib_index)
 766     {
 767       vec_validate (dpm->dhcp_server_index_by_rx_fib_index, rx_fib_index);
 768       dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] =
 769         server - dpm->dhcp_servers;
 770     }
 771
 772   return 0;
 773 }
 774
 775 /* Old API, manipulates the default server (only) */
 776 int dhcp_proxy_set_server (ip4_address_t *addr, ip4_address_t *src_address,
 777                            u32 fib_id, int insert_option_82, int is_del)
 778 {
 779   return dhcp_proxy_set_server_2 (addr, src_address, 0 /* rx_fib_id */,
 780                                   fib_id /* server_fib_id */,
 781                                   insert_option_82, is_del);
 782 }
 783
 784
 785 static clib_error_t *
 786 dhcp_proxy_set_command_fn (vlib_main_t * vm,
 787                            unformat_input_t * input,
 788                            vlib_cli_command_t * cmd)
 789 {
 790   ip4_address_t server_addr, src_addr;
 791   u32 server_fib_id = 0, rx_fib_id = 0;
 792   int is_del = 0;
 793   int add_option_82 = 0;
 794   int set_src = 0, set_server = 0;
 795
 796   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
 797     {
 798       if (unformat (input, "server %U",
 799                     unformat_ip4_address, &server_addr))
 800         set_server = 1;
 801       else if (unformat (input, "server-fib-id %d", &server_fib_id))
 802         ;
 803       else if (unformat (input, "rx-fib-id %d", &rx_fib_id))
 804         ;
 805       else if (unformat(input, "src-address %U",
 806                         unformat_ip4_address, &src_addr))
 807         set_src = 1;
 808       else if (unformat (input, "add-option-82")
 809                || unformat (input, "insert-option-82"))
 810         add_option_82 = 1;
 811       else if (unformat (input, "delete") ||
 812                unformat (input, "del"))
 813         is_del = 1;
 814       else
 815         break;
 816     }
 817
 818   if (is_del || (set_server && set_src))
 819     {
 820       int rv;
 821
 822       rv = dhcp_proxy_set_server_2 (&server_addr, &src_addr, rx_fib_id,
 823                                     server_fib_id, add_option_82, is_del);
 824       switch (rv)
 825         {
 826         case 0:
 827           return 0;
 828
 829         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 830           return clib_error_return (0, "Invalid server address");
 831
 832         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 833           return clib_error_return (0, "Invalid src address");
 834
 835         case VNET_API_ERROR_NO_SUCH_INNER_FIB:
 836           return clib_error_return (0, "No such rx fib id %d", rx_fib_id);
 837
 838         case VNET_API_ERROR_NO_SUCH_FIB:
 839           return clib_error_return (0, "No such server fib id %d",
 840                                     server_fib_id);
 841
 842         case VNET_API_ERROR_NO_SUCH_ENTRY:
 843           return clib_error_return
 844             (0, "Fib id %d: no per-fib DHCP server configured", rx_fib_id);
 845
 846         default:
 847           return clib_error_return (0, "BUG: rv %d", rv);
 848         }
 849     }
 850   else
 851     return clib_error_return (0, "parse error`%U'",
 852                               format_unformat_error, input);
 853 }
 854
 855 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 856   .path = "set dhcp proxy",
 857   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [add-option-82] [server-fib-id <n>] [rx-fib-id <n>]",
 858   .function = dhcp_proxy_set_command_fn,
 859 };
 860
 861 u8 * format_dhcp_proxy_server (u8 * s, va_list * args)
 862 {
 863   dhcp_proxy_main_t * dm = va_arg (*args, dhcp_proxy_main_t *);
 864   dhcp_server_t * server = va_arg (*args, dhcp_server_t *);
 865   u32 rx_fib_index = va_arg (*args, u32);
 866   ip4_fib_t * rx_fib, * server_fib;
 867   u32 server_fib_id = ~0, rx_fib_id = ~0;
 868
 869   if (dm == 0)
 870     {
 871       s = format (s, "%=16s%=16s%=14s%=14s%=20s", "Server", "Src Address",
 872                   "Server FIB", "RX FIB", "Insert Option 82");
 873       return s;
 874     }
 875
 876   server_fib = ip4_fib_get(server->server_fib_index);
 877
 878   if (server_fib)
 879     server_fib_id = server_fib->table_id;
 880
 881   rx_fib = ip4_fib_get(rx_fib_index);
 882
 883   if (rx_fib)
 884     rx_fib_id = rx_fib->table_id;
 885
 886   s = format (s, "%=16U%=16U%=14u%=14u%=20s",
 887               format_ip4_address, &server->dhcp_server,
 888               format_ip4_address, &server->dhcp_src_address,
 889               server_fib_id, rx_fib_id,
 890               server->insert_option_82 ? "yes" : "no");
 891   return s;
 892 }
 893
 894 static clib_error_t *
 895 dhcp_proxy_show_command_fn (vlib_main_t * vm,
 896                             unformat_input_t * input,
 897                             vlib_cli_command_t * cmd)
 898 {
 899   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 900   ip4_main_t * im = &ip4_main;
 901   dhcp_server_t * server;
 902   u32 server_index;
 903   int i;
 904
 905   vlib_cli_output (vm, "%U", format_dhcp_proxy_server, 0 /* header line */,
 906                    0, 0);
 907
 908   for (i = 0; i < vec_len (im->fibs); i++)
 909     {
 910       if (i < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 911         server_index = dpm->dhcp_server_index_by_rx_fib_index[i];
 912       else
 913         server_index = 0;
 914       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 915       if (server->valid)
 916         vlib_cli_output (vm, "%U", format_dhcp_proxy_server, dpm,
 917                          server, i);
 918     }
 919
 920   return 0;
 921 }
 922
 923 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 924   .path = "show dhcp proxy",
 925   .short_help = "Display dhcp proxy server info",
 926   .function = dhcp_proxy_show_command_fn,
 927 };
 928
 929
 930 int dhcp_proxy_set_option82_vss(  u32 vrf_id,
 931                                   u32 oui,
 932                                   u32 fib_id,
 933                                   int is_del)
 934 {
 935   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 936   uword *p;
 937   vss_info *a;
 938   u32 old_oui=0, old_fib_id=0;
 939
 940   p = hash_get (dm->opt82vss_index_by_vrf_id, vrf_id);
 941
 942   if (p)
 943     {
 944       a = pool_elt_at_index (dm->opt82vss, p[0]);
 945       if (!a)
 946         return VNET_API_ERROR_NO_SUCH_FIB;
 947       old_oui = a->vpn_id.oui;
 948       old_fib_id = a->vpn_id.fib_id;
 949
 950       if (is_del)
 951         {
 952           if (old_oui == oui &&
 953               old_fib_id == fib_id)
 954             {
 955               pool_put(dm->opt82vss, a);
 956               hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
 957               return 0;
 958             }
 959           else
 960             return VNET_API_ERROR_NO_SUCH_ENTRY;
 961         }
 962       pool_put(dm->opt82vss, a);
 963       hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
 964   } else if (is_del)
 965     return VNET_API_ERROR_NO_SUCH_ENTRY;
 966   pool_get (dm->opt82vss, a);
 967   memset (a, ~0, sizeof (a[0]));
 968   a->vpn_id.oui = oui;
 969   a->vpn_id.fib_id = fib_id;
 970   hash_set (dm->opt82vss_index_by_vrf_id, vrf_id, a - dm->opt82vss);
 971
 972   return 0;
 973 }
 974
 975 static clib_error_t *
 976 dhcp_option_82_vss_fn (vlib_main_t * vm,
 977                         unformat_input_t * input,
 978                         vlib_cli_command_t * cmd)
 979 {
 980   int is_del = 0, got_new_vpn_id=0;
 981   u32 oui=0, fib_id=0, tbl_id=~0;
 982
 983
 984   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
 985     {
 986
 987       if (unformat(input, "delete") || unformat(input, "del"))
 988           is_del = 1;
 989       else if (unformat (input, "oui %d", &oui))
 990           got_new_vpn_id = 1;
 991       else if (unformat (input, "vpn-id %d", &fib_id))
 992           got_new_vpn_id = 1;
 993       else if (unformat (input, "table %d", &tbl_id))
 994           got_new_vpn_id = 1;
 995       else
 996           break;
 997   }
 998   if (tbl_id == ~0)
 999       return clib_error_return (0, "no table ID specified.");
1000
1001   if (is_del || got_new_vpn_id)
1002     {
1003       int rv;
1004       rv = dhcp_proxy_set_option82_vss(tbl_id, oui, fib_id, is_del);
1005       switch (rv)
1006         {
1007         case 0:
1008             return 0;
1009
1010         case VNET_API_ERROR_NO_SUCH_FIB:
1011             return clib_error_return (0, "option 82 vss(oui:%d, vpn-id:%d) not found in table %d",
1012                                       oui, fib_id, tbl_id);
1013
1014         case VNET_API_ERROR_NO_SUCH_ENTRY:
1015             return clib_error_return (0, "option 82 vss for table %d not found in in pool.",
1016                                       tbl_id);
1017         default:
1018           return clib_error_return (0, "BUG: rv %d", rv);
1019         }
1020     }
1021   else
1022       return clib_error_return (0, "parse error`%U'",
1023                                 format_unformat_error, input);
1024 }
1025
1026 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
1027   .path = "set dhcp option-82 vss",
1028   .short_help = "set dhcp option-82 vss [del] table <table id> oui <oui> vpn-id <vpn-id>",
1029   .function = dhcp_option_82_vss_fn,
1030 };
1031
1032
1033 static clib_error_t *
1034 dhcp_vss_show_command_fn (vlib_main_t * vm,
1035                           unformat_input_t * input,
1036                           vlib_cli_command_t * cmd)
1037
1038 {
1039   dhcp_proxy_main_t * dm = &dhcp_proxy_main;
1040   vss_info *v;
1041   u32 oui;
1042   u32 fib_id;
1043   u32 tbl_id;
1044   uword index;
1045
1046   vlib_cli_output (vm, "%=9s%=11s%=12s","Table", "OUI", "VPN-ID");
1047   hash_foreach (tbl_id, index, dm->opt82vss_index_by_vrf_id,
1048   ({
1049      v = pool_elt_at_index (dm->opt82vss, index);
1050      oui = v->vpn_id.oui;
1051      fib_id = v->vpn_id.fib_id;
1052      vlib_cli_output (vm, "%=9d 0x%08x%=12d",
1053                       tbl_id, oui, fib_id);
1054   }));
1055
1056   return 0;
1057 }
1058
1059 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1060   .path = "show dhcp vss",
1061   .short_help = "show dhcp VSS",
1062   .function = dhcp_vss_show_command_fn,
1063 };
1064
1065 static clib_error_t *
1066 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1067                                 unformat_input_t * input,
1068                                 vlib_cli_command_t * cmd)
1069
1070 {
1071   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
1072   vnet_main_t *vnm = vnet_get_main();
1073   u32 sw_if_index0=0, sw_if_index;
1074   ip4_address_t *ia0;
1075   vnet_sw_interface_t *swif;
1076
1077   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
1078     {
1079
1080       if (unformat(input, "%U",
1081                    unformat_vnet_sw_interface, dm->vnet_main, &sw_if_index0))
1082         {
1083           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1084           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1085             swif->unnumbered_sw_if_index : sw_if_index0;
1086           ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
1087           if (ia0)
1088             {
1089               vlib_cli_output (vm, "%=20s%=20s", "interface",
1090                                "source IP address");
1091
1092               vlib_cli_output (vm, "%=20U%=20U",
1093                                format_vnet_sw_if_index_name,
1094                                dm->vnet_main, sw_if_index0,
1095                                format_ip4_address, ia0);
1096             }
1097           else
1098             vlib_cli_output (vm, "%=34s %=20U",
1099                              "No IPv4 address configured on",
1100                              format_vnet_sw_if_index_name,
1101                              dm->vnet_main, sw_if_index);
1102         }
1103       else
1104         break;
1105     }
1106
1107   return 0;
1108 }
1109
1110 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1111   .path = "show dhcp option-82-address interface",
1112   .short_help = "show dhcp option-82-address interface <interface>",
1113   .function = dhcp_option_82_address_show_command_fn,
1114 };