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
  22 static char * dhcp_proxy_error_strings[] = {
  23 #define dhcp_proxy_error(n,s) s,
  24 #include "proxy_error.def"
  25 #undef dhcp_proxy_error
  26 };
  27
  28 #define foreach_dhcp_proxy_to_server_input_next \
  29   _ (DROP, "error-drop")                        \
  30   _ (LOOKUP, "ip4-lookup")                      \
  31   _ (SEND_TO_CLIENT, "dhcp-proxy-to-client")
  32
  33 typedef enum {
  34 #define _(s,n) DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s,
  35   foreach_dhcp_proxy_to_server_input_next
  36 #undef _
  37   DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
  38 } dhcp_proxy_to_server_input_next_t;
  39
  40 typedef struct {
  41   /* 0 => to server, 1 => to client */
  42   int which;
  43   ip4_address_t trace_ip4_address;
  44   u32 error;
  45   u32 sw_if_index;
  46   u32 original_sw_if_index;
  47 } dhcp_proxy_trace_t;
  48
  49 #define VPP_DHCP_OPTION82_SUB1_SIZE   6
  50 #define VPP_DHCP_OPTION82_SUB5_SIZE   6
  51 #define VPP_DHCP_OPTION82_VSS_SIZE    12
  52 #define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
  53                                 VPP_DHCP_OPTION82_SUB5_SIZE + \
  54                                 VPP_DHCP_OPTION82_VSS_SIZE +3)
  55
  56 vlib_node_registration_t dhcp_proxy_to_server_node;
  57 vlib_node_registration_t dhcp_proxy_to_client_node;
  58
  59 u8 * format_dhcp_proxy_trace (u8 * s, va_list * args)
  60 {
  61   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  62   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  63   dhcp_proxy_trace_t * t = va_arg (*args, dhcp_proxy_trace_t *);
  64
  65   if (t->which == 0)
  66     s = format (s, "DHCP proxy: sent to server %U\n",
  67                 format_ip4_address, &t->trace_ip4_address, t->error);
  68   else
  69     s = format (s, "DHCP proxy: broadcast to client from %U\n",
  70                 format_ip4_address, &t->trace_ip4_address);
  71
  72   if (t->error != (u32)~0)
  73     s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
  74
  75   s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
  76               t->original_sw_if_index, t->sw_if_index);
  77
  78   return s;
  79 }
  80
  81 u8 * format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
  82 {
  83   dhcp_header_t * h = va_arg (*args, dhcp_header_t *);
  84   u32 max_header_bytes = va_arg (*args, u32);
  85   u32 header_bytes;
  86
  87   header_bytes = sizeof (h[0]);
  88   if (max_header_bytes != 0 && header_bytes > max_header_bytes)
  89     return format (s, "dhcp header truncated");
  90
  91   s = format (s, "DHCP Proxy");
  92
  93   return s;
  94 }
  95
  96 /* get first interface address */
  97 static ip4_address_t *
  98 ip4_interface_first_address (ip4_main_t * im, u32 sw_if_index)
  99 {
 100   ip_lookup_main_t * lm = &im->lookup_main;
 101   ip_interface_address_t * ia = 0;
 102   ip4_address_t * result = 0;
 103
 104   foreach_ip_interface_address (lm, ia, sw_if_index,
 105                                 1 /* honor unnumbered */,
 106   ({
 107     ip4_address_t * a = ip_interface_address_get_address (lm, ia);
 108     result = a;
 109     break;
 110   }));
 111   return result;
 112 }
 113
 114 static uword
 115 dhcp_proxy_to_server_input (vlib_main_t * vm,
 116                             vlib_node_runtime_t * node,
 117                             vlib_frame_t * from_frame)
 118 {
 119   u32 n_left_from, next_index, * from, * to_next;
 120   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 121   from = vlib_frame_vector_args (from_frame);
 122   n_left_from = from_frame->n_vectors;
 123   u32 pkts_to_server=0, pkts_to_client=0, pkts_no_server=0;
 124   u32 pkts_no_interface_address=0;
 125   u32 pkts_too_big=0;
 126   ip4_main_t * im = &ip4_main;
 127
 128   next_index = node->cached_next_index;
 129
 130   while (n_left_from > 0)
 131     {
 132       u32 n_left_to_next;
 133
 134       vlib_get_next_frame (vm, node, next_index,
 135                            to_next, n_left_to_next);
 136
 137       while (n_left_from > 0 && n_left_to_next > 0)
 138         {
 139           u32 bi0;
 140           vlib_buffer_t * b0;
 141           udp_header_t * u0;
 142           dhcp_header_t * h0;
 143           ip4_header_t * ip0;
 144           u32 next0;
 145           u32 old0, new0;
 146           ip_csum_t sum0;
 147           u32 error0 = (u32) ~0;
 148           u32 sw_if_index = 0;
 149           u32 original_sw_if_index = 0;
 150           u8  *end = NULL;
 151           u32 fib_index, server_index;
 152           dhcp_server_t * server;
 153           u32 rx_sw_if_index;
 154
 155           bi0 = from[0];
 156           to_next[0] = bi0;
 157           from += 1;
 158           to_next += 1;
 159           n_left_from -= 1;
 160           n_left_to_next -= 1;
 161
 162           b0 = vlib_get_buffer (vm, bi0);
 163
 164           h0 = vlib_buffer_get_current (b0);
 165
 166           /*
 167            * udp_local hands us the DHCP header, need udp hdr,
 168            * ip hdr to relay to server
 169            */
 170           vlib_buffer_advance (b0, -(sizeof(*u0)));
 171           u0 = vlib_buffer_get_current (b0);
 172
 173           /* This blows. Return traffic has src_port = 67, dst_port = 67 */
 174           if (u0->src_port == clib_net_to_host_u16(UDP_DST_PORT_dhcp_to_server))
 175             {
 176               vlib_buffer_advance (b0, sizeof(*u0));
 177               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
 178               error0 = 0;
 179               pkts_to_client++;
 180               goto do_enqueue;
 181             }
 182
 183           rx_sw_if_index = vnet_buffer(b0)->sw_if_index[VLIB_RX];
 184
 185           fib_index = im->fib_index_by_sw_if_index [rx_sw_if_index];
 186
 187           if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 188             server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
 189           else
 190             server_index = 0;
 191
 192           if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers,
 193                                                  server_index)))
 194             {
 195             no_server:
 196               error0 = DHCP_PROXY_ERROR_NO_SERVER;
 197               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 198               pkts_no_server++;
 199               goto do_trace;
 200             }
 201
 202           server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 203           if (server->valid == 0)
 204             goto no_server;
 205
 206           vlib_buffer_advance (b0, -(sizeof(*ip0)));
 207           ip0 = vlib_buffer_get_current (b0);
 208
 209           /* disable UDP checksum */
 210           u0->checksum = 0;
 211           sum0 = ip0->checksum;
 212           old0 = ip0->dst_address.as_u32;
 213           new0 = server->dhcp_server.as_u32;
 214           ip0->dst_address.as_u32 = server->dhcp_server.as_u32;
 215           sum0 = ip_csum_update (sum0, old0, new0,
 216                                 ip4_header_t /* structure */,
 217                                 dst_address /* changed member */);
 218           ip0->checksum = ip_csum_fold (sum0);
 219
 220           sum0 = ip0->checksum;
 221           old0 = ip0->src_address.as_u32;
 222           new0 = server->dhcp_src_address.as_u32;
 223           ip0->src_address.as_u32 = new0;
 224           sum0 = ip_csum_update (sum0, old0, new0,
 225                                 ip4_header_t /* structure */,
 226                                 src_address /* changed member */);
 227           ip0->checksum = ip_csum_fold (sum0);
 228
 229           /* Send to DHCP server via the configured FIB */
 230           vnet_buffer(b0)->sw_if_index[VLIB_TX] =
 231             server->server_fib_index;
 232
 233           h0->gateway_ip_address.as_u32 = server->dhcp_src_address.as_u32;
 234           pkts_to_server++;
 235
 236           if (server->insert_option_82)
 237             {
 238               u32 fib_index, fib_id, opt82_fib_id=0, opt82_oui=0;
 239               ip4_fib_t * fib;
 240               dhcp_option_t *o = (dhcp_option_t *) h0->options;
 241               u32 len = 0;
 242               vlib_buffer_free_list_t *fl;
 243
 244               fib_index = im->fib_index_by_sw_if_index
 245                 [vnet_buffer(b0)->sw_if_index[VLIB_RX]];
 246               fib = vec_elt_at_index (im->fibs, fib_index);
 247               fib_id = fib->table_id;
 248
 249               end = b0->data + b0->current_data + b0->current_length;
 250               /* TLVs are not performance-friendly... */
 251               while  (o->option != 0xFF /* end of options */ && (u8 *)o < end)
 252                   o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 253
 254               fl = vlib_buffer_get_free_list (vm, b0->free_list_index);
 255               // start write at (option*)o, some packets have padding
 256               if (((u8 *)o - (u8 *)b0->data + VPP_DHCP_OPTION82_SIZE) > fl->n_data_bytes)
 257                 {
 258                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 259                   pkts_too_big++;
 260                   goto do_trace;
 261                 }
 262
 263               if ((o->option == 0xFF)  && ((u8 *)o <= end))
 264                 {
 265                   vnet_main_t *vnm = vnet_get_main();
 266                   u16 old_l0, new_l0;
 267                   ip4_address_t _ia0, * ia0 = &_ia0;
 268                   uword  *p_vss;
 269                   vss_info *vss;
 270                   vnet_sw_interface_t *swif;
 271                   sw_if_index = 0;
 272                   original_sw_if_index = 0;
 273
 274                   original_sw_if_index = sw_if_index =
 275                       vnet_buffer(b0)->sw_if_index[VLIB_RX];
 276                   swif = vnet_get_sw_interface (vnm, sw_if_index);
 277                   if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 278                       sw_if_index = swif->unnumbered_sw_if_index;
 279
 280                   p_vss = hash_get (dpm->opt82vss_index_by_vrf_id,
 281                                     fib_id);
 282                   if (p_vss)
 283                     {
 284                       vss = pool_elt_at_index (dpm->opt82vss, p_vss[0]);
 285                       opt82_oui =  vss->vpn_id.oui;
 286                       opt82_fib_id =  vss->vpn_id.fib_id;
 287                     }
 288                   /*
 289                    * Get the first ip4 address on the [client-side]
 290                    * RX interface, if not unnumbered. otherwise use
 291                    * the loopback interface's ip address.
 292                    */
 293                   ia0 = ip4_interface_first_address(&ip4_main, sw_if_index);
 294
 295                   if (ia0 == 0)
 296                     {
 297                       error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 298                       next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 299                       pkts_no_interface_address++;
 300                       goto do_trace;
 301                     }
 302
 303                   /* Add option 82 */
 304                   o->option = 82;   /* option 82 */
 305                   o->length = 12;   /* 12 octets to follow */
 306                   o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
 307                   o->data[1] = 4;   /* length of suboption */
 308                   o->data[2] = (original_sw_if_index >> 24) & 0xFF;
 309                   o->data[3] = (original_sw_if_index >> 16) & 0xFF;
 310                   o->data[4] = (original_sw_if_index >> 8)  & 0xFF;
 311                   o->data[5] = (original_sw_if_index >> 0)  & 0xFF;
 312                   o->data[6] = 5; /* suboption 5 (client RX intfc address) */
 313                   o->data[7] = 4; /* length 4 */
 314                   o->data[8] = ia0->as_u8[0];
 315                   o->data[9] = ia0->as_u8[1];
 316                   o->data[10] = ia0->as_u8[2];
 317                   o->data[11] = ia0->as_u8[3];
 318                   o->data[12] = 0xFF;
 319                   if (opt82_oui !=0 || opt82_fib_id != 0)
 320                     {
 321                       o->data[12] = 151; /* vss suboption */
 322                       if (255 == opt82_fib_id) {
 323                           o->data[13] = 1;   /* length */
 324                           o->data[14] = 255;   /* vss option type */
 325                           o->data[15] = 152; /* vss control suboption */
 326                           o->data[16] = 0;   /* length */
 327                           /* and a new "end-of-options" option (0xff) */
 328                           o->data[17] = 0xFF;
 329                           o->length += 5;
 330                       } else {
 331                           o->data[13] = 8;   /* length */
 332                           o->data[14] = 1;   /* vss option type */
 333                           o->data[15] = (opt82_oui >> 16) & 0xff;
 334                           o->data[16] = (opt82_oui >> 8) & 0xff;
 335                           o->data[17] = (opt82_oui ) & 0xff;
 336                           o->data[18] = (opt82_fib_id >> 24) & 0xff;
 337                           o->data[19] = (opt82_fib_id >> 16) & 0xff;
 338                           o->data[20] = (opt82_fib_id >> 8) & 0xff;
 339                           o->data[21] = (opt82_fib_id) & 0xff;
 340                           o->data[22] = 152; /* vss control suboption */
 341                           o->data[23] = 0;   /* length */
 342
 343                           /* and a new "end-of-options" option (0xff) */
 344                           o->data[24] = 0xFF;
 345                           o->length += 12;
 346                       }
 347                   }
 348
 349                   len = o->length + 3;
 350                   b0->current_length += len;
 351                   /* Fix IP header length and checksum */
 352                   old_l0 = ip0->length;
 353                   new_l0 = clib_net_to_host_u16 (old_l0);
 354                   new_l0 += len;
 355                   new_l0 = clib_host_to_net_u16 (new_l0);
 356                   ip0->length = new_l0;
 357                   sum0 = ip0->checksum;
 358                   sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 359                                          length /* changed member */);
 360                   ip0->checksum = ip_csum_fold (sum0);
 361
 362                   /* Fix UDP length */
 363                   new_l0 = clib_net_to_host_u16 (u0->length);
 364                   new_l0 += len;
 365                   u0->length = clib_host_to_net_u16 (new_l0);
 366                 } else {
 367                   vlib_node_increment_counter
 368                       (vm, dhcp_proxy_to_server_node.index,
 369                        DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
 370                 }
 371             }
 372
 373           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
 374
 375         do_trace:
 376           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 377             {
 378                dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 379                                                         b0, sizeof (*tr));
 380                tr->which = 0; /* to server */
 381                tr->error = error0;
 382                tr->original_sw_if_index = original_sw_if_index;
 383                tr->sw_if_index = sw_if_index;
 384                if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 385                  tr->trace_ip4_address.as_u32 = server->dhcp_server.as_u32;
 386             }
 387
 388         do_enqueue:
 389           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 390                                            to_next, n_left_to_next,
 391                                            bi0, next0);
 392         }
 393
 394       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 395     }
 396
 397   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 398                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
 399                                pkts_to_client);
 400   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 401                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
 402                                pkts_to_server);
 403   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 404                                DHCP_PROXY_ERROR_NO_SERVER,
 405                                pkts_no_server);
 406   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 407                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
 408                                pkts_no_interface_address);
 409  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 410                               DHCP_PROXY_ERROR_PKT_TOO_BIG,
 411                               pkts_too_big);
 412   return from_frame->n_vectors;
 413 }
 414
 415 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node) = {
 416   .function = dhcp_proxy_to_server_input,
 417   .name = "dhcp-proxy-to-server",
 418   /* Takes a vector of packets. */
 419   .vector_size = sizeof (u32),
 420
 421   .n_errors = DHCP_PROXY_N_ERROR,
 422   .error_strings = dhcp_proxy_error_strings,
 423
 424   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
 425   .next_nodes = {
 426 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
 427     foreach_dhcp_proxy_to_server_input_next
 428 #undef _
 429   },
 430
 431   .format_buffer = format_dhcp_proxy_header_with_length,
 432   .format_trace = format_dhcp_proxy_trace,
 433 #if 0
 434   .unformat_buffer = unformat_dhcp_proxy_header,
 435 #endif
 436 };
 437
 438 static uword
 439 dhcp_proxy_to_client_input (vlib_main_t * vm,
 440                             vlib_node_runtime_t * node,
 441                             vlib_frame_t * from_frame)
 442 {
 443   u32 n_left_from, * from;
 444   ethernet_main_t *em = ethernet_get_main (vm);
 445   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 446   vnet_main_t * vnm = vnet_get_main();
 447   ip4_main_t * im = &ip4_main;
 448
 449   from = vlib_frame_vector_args (from_frame);
 450   n_left_from = from_frame->n_vectors;
 451
 452   while (n_left_from > 0)
 453     {
 454       u32 bi0;
 455       vlib_buffer_t * b0;
 456       udp_header_t * u0;
 457       dhcp_header_t * h0;
 458       ip4_header_t * ip0 = 0;
 459       ip4_address_t * ia0 = 0;
 460       u32 old0, new0;
 461       ip_csum_t sum0;
 462       ethernet_interface_t *ei0;
 463       ethernet_header_t *mac0;
 464       vnet_hw_interface_t *hi0;
 465       vlib_frame_t *f0;
 466       u32 * to_next0;
 467       u32 sw_if_index = ~0;
 468       vnet_sw_interface_t *si0;
 469       u32 error0 = (u32)~0;
 470       vnet_sw_interface_t *swif;
 471       u32 server_index;
 472       u32 fib_index;
 473       dhcp_server_t * server;
 474       u32 original_sw_if_index = (u32) ~0;
 475
 476       bi0 = from[0];
 477       from += 1;
 478       n_left_from -= 1;
 479
 480       b0 = vlib_get_buffer (vm, bi0);
 481       h0 = vlib_buffer_get_current (b0);
 482
 483       /*
 484        * udp_local hands us the DHCP header, need udp hdr,
 485        * ip hdr to relay to client
 486        */
 487       vlib_buffer_advance (b0, -(sizeof(*u0)));
 488       u0 = vlib_buffer_get_current (b0);
 489
 490       vlib_buffer_advance (b0, -(sizeof(*ip0)));
 491       ip0 = vlib_buffer_get_current (b0);
 492
 493       /* Consumed by dhcp client code? */
 494       if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
 495           continue;
 496
 497       if (1 /* dpm->insert_option_82 */)
 498         {
 499           dhcp_option_t *o = (dhcp_option_t *) h0->options;
 500           dhcp_option_t *sub;
 501
 502           /* Parse through TLVs looking for option 82.
 503              The circuit-ID is the FIB number we need
 504              to track down the client-facing interface */
 505
 506           while (o->option != 0xFF /* end of options */ &&
 507                  (u8 *) o < (b0->data + b0->current_data + b0->current_length))
 508             {
 509               if (o->option == 82)
 510                 {
 511                     u32 vss_exist = 0;
 512                     u32 vss_ctrl = 0;
 513                     sub = (dhcp_option_t *) &o->data[0];
 514                     while (sub->option != 0xFF /* end of options */ &&
 515                            (u8 *) sub < (u8 *)(o + o->length)) {
 516                         /* If this is one of ours, it will have
 517                            total length 12, circuit-id suboption type,
 518                            and the sw_if_index */
 519                         if (sub->option == 1 && sub->length == 4)
 520                           {
 521                             sw_if_index = (o->data[2] << 24)
 522                                 | (o->data[3] << 16)
 523                                 | (o->data[4] << 8)
 524                                 | (o->data[5]);
 525                           } else if (sub->option == 151 &&
 526                                      sub->length == 7 &&
 527                                      sub->data[0] == 1)
 528                             vss_exist = 1;
 529                         else if (sub->option == 152 && sub->length == 0)
 530                             vss_ctrl = 1;
 531                         sub = (dhcp_option_t *)
 532                           (((uword) sub) + (sub->length + 2));
 533                     }
 534                     if (vss_ctrl && vss_exist)
 535                       vlib_node_increment_counter
 536                         (vm, dhcp_proxy_to_client_node.index,
 537                          DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 538
 539                 }
 540               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 541             }
 542         }
 543
 544       if (sw_if_index == (u32)~0)
 545         {
 546           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 547
 548         drop_packet:
 549           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 550                                        error0, 1);
 551           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 552           to_next0 = vlib_frame_vector_args (f0);
 553           to_next0[0] = bi0;
 554           f0->n_vectors = 1;
 555           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 556           goto do_trace;
 557         }
 558
 559
 560       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 561         {
 562           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
 563           goto drop_packet;
 564         }
 565
 566       fib_index = im->fib_index_by_sw_if_index [sw_if_index];
 567
 568       if (fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 569         server_index = dpm->dhcp_server_index_by_rx_fib_index[fib_index];
 570       else
 571         server_index = 0;
 572
 573       if (PREDICT_FALSE (pool_is_free_index (dpm->dhcp_servers,
 574                                              server_index)))
 575         {
 576           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82;
 577           goto drop_packet;
 578         }
 579
 580       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 581       if (server->valid == 0)
 582         {
 583           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 584           goto drop_packet;
 585         }
 586
 587       if (ip0->src_address.as_u32 != server->dhcp_server.as_u32)
 588         {
 589           error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 590           goto drop_packet;
 591         }
 592
 593       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 594
 595       swif = vnet_get_sw_interface (vnm, sw_if_index);
 596       original_sw_if_index = sw_if_index;
 597       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 598           sw_if_index = swif->unnumbered_sw_if_index;
 599
 600       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index);
 601       if (ia0 == 0)
 602         {
 603           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 604           goto drop_packet;
 605         }
 606
 607       u0->checksum = 0;
 608       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 609       sum0 = ip0->checksum;
 610       old0 = ip0->dst_address.as_u32;
 611       new0 = 0xFFFFFFFF;
 612       ip0->dst_address.as_u32 = new0;
 613       sum0 = ip_csum_update (sum0, old0, new0,
 614                             ip4_header_t /* structure */,
 615                             dst_address /* offset of changed member */);
 616       ip0->checksum = ip_csum_fold (sum0);
 617
 618       sum0 = ip0->checksum;
 619       old0 = ip0->src_address.as_u32;
 620       new0 = ia0->as_u32;
 621       ip0->src_address.as_u32 = new0;
 622       sum0 = ip_csum_update (sum0, old0, new0,
 623                             ip4_header_t /* structure */,
 624                             src_address /* offset of changed member */);
 625       ip0->checksum = ip_csum_fold (sum0);
 626
 627       vlib_buffer_advance (b0, -(sizeof(ethernet_header_t)));
 628       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 629       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 630           vlib_buffer_advance (b0, -4 /* space for VLAN tag */);
 631
 632       mac0 = vlib_buffer_get_current (b0);
 633
 634       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 635       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 636       memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 637       memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 638       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 639         clib_net_to_host_u16(0x8100) : clib_net_to_host_u16 (0x0800);
 640
 641       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 642         {
 643           u32 * vlan_tag = (u32 *)(mac0+1);
 644           u32 tmp;
 645           tmp = (si0->sub.id << 16) | 0x0800;
 646           *vlan_tag = clib_host_to_net_u32 (tmp);
 647         }
 648
 649       /* $$$ This needs to be rewritten, for sure */
 650       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 651       to_next0 = vlib_frame_vector_args (f0);
 652       to_next0[0] = bi0;
 653       f0->n_vectors = 1;
 654       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 655
 656     do_trace:
 657       if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 658         {
 659           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 660                                                    b0, sizeof (*tr));
 661           tr->which = 1; /* to client */
 662           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 663           tr->error = error0;
 664           tr->original_sw_if_index = original_sw_if_index;
 665           tr->sw_if_index = sw_if_index;
 666         }
 667     }
 668   return from_frame->n_vectors;
 669 }
 670
 671 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node) = {
 672   .function = dhcp_proxy_to_client_input,
 673   .name = "dhcp-proxy-to-client",
 674   /* Takes a vector of packets. */
 675   .vector_size = sizeof (u32),
 676
 677   .n_errors = DHCP_PROXY_N_ERROR,
 678   .error_strings = dhcp_proxy_error_strings,
 679   .format_buffer = format_dhcp_proxy_header_with_length,
 680   .format_trace = format_dhcp_proxy_trace,
 681 #if 0
 682   .unformat_buffer = unformat_dhcp_proxy_header,
 683 #endif
 684 };
 685
 686 clib_error_t * dhcp_proxy_init (vlib_main_t * vm)
 687 {
 688   dhcp_proxy_main_t * dm = &dhcp_proxy_main;
 689   vlib_node_t * error_drop_node;
 690   dhcp_server_t * server;
 691
 692   dm->vlib_main = vm;
 693   dm->vnet_main = vnet_get_main();
 694   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 695   dm->error_drop_node_index = error_drop_node->index;
 696
 697   dm->opt82vss_index_by_vrf_id = hash_create (0, sizeof (uword));
 698
 699   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
 700                          dhcp_proxy_to_client_node.index, 1 /* is_ip4 */);
 701
 702   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
 703                          dhcp_proxy_to_server_node.index, 1 /* is_ip4 */);
 704
 705   /* Create the default server, don't mark it valid */
 706   pool_get (dm->dhcp_servers, server);
 707   memset (server, 0, sizeof (*server));
 708
 709   return 0;
 710 }
 711
 712 VLIB_INIT_FUNCTION (dhcp_proxy_init);
 713
 714 int dhcp_proxy_set_server_2 (ip4_address_t *addr, ip4_address_t *src_address,
 715                              u32 rx_fib_id,
 716                              u32 server_fib_id,
 717                              int insert_option_82, int is_del)
 718 {
 719   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 720   ip4_main_t * im = &ip4_main;
 721   dhcp_server_t * server = 0;
 722   ip4_fib_t *rx_fib, *server_fib;
 723   u32 server_index = 0;
 724   u32 rx_fib_index = 0;
 725
 726   if (addr->as_u32 == 0)
 727     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 728
 729   if (src_address->as_u32 == 0)
 730     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 731
 732   rx_fib = find_ip4_fib_by_table_index_or_id
 733     (&ip4_main, rx_fib_id, IP4_ROUTE_FLAG_TABLE_ID);
 734
 735   if (rx_fib == 0)
 736     return VNET_API_ERROR_NO_SUCH_INNER_FIB;
 737
 738   server_fib = find_ip4_fib_by_table_index_or_id
 739     (&ip4_main, server_fib_id, IP4_ROUTE_FLAG_TABLE_ID);
 740
 741   if (server_fib == 0)
 742     return VNET_API_ERROR_NO_SUCH_FIB;
 743
 744   if (rx_fib_id == 0)
 745     {
 746       server = pool_elt_at_index (dpm->dhcp_servers, 0);
 747
 748       if (is_del)
 749         {
 750           memset (server, 0, sizeof (*server));
 751           return 0;
 752         }
 753       goto initialize_it;
 754     }
 755
 756   rx_fib_index = rx_fib - im->fibs;
 757
 758   if (is_del)
 759     {
 760       if (rx_fib_index >= vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 761         return VNET_API_ERROR_NO_SUCH_ENTRY;
 762
 763       server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
 764       ASSERT(server_index > 0);
 765
 766       /* Use the default server again.  */
 767       dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] = 0;
 768       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 769       memset (server, 0, sizeof (*server));
 770       pool_put (dpm->dhcp_servers, server);
 771       return 0;
 772     }
 773
 774   if (rx_fib_index < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 775     {
 776       server_index = dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index];
 777       if (server_index != 0)
 778         {
 779           server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 780           goto initialize_it;
 781         }
 782     }
 783
 784   pool_get (dpm->dhcp_servers, server);
 785
 786  initialize_it:
 787
 788   server->dhcp_server.as_u32 = addr->as_u32;
 789   server->server_fib_index = server_fib - im->fibs;
 790   server->dhcp_src_address.as_u32 = src_address->as_u32;
 791   server->insert_option_82 = insert_option_82;
 792   server->valid = 1;
 793   if (rx_fib_index)
 794     {
 795       vec_validate (dpm->dhcp_server_index_by_rx_fib_index, rx_fib_index);
 796       dpm->dhcp_server_index_by_rx_fib_index[rx_fib_index] =
 797         server - dpm->dhcp_servers;
 798     }
 799
 800   return 0;
 801 }
 802
 803 /* Old API, manipulates the default server (only) */
 804 int dhcp_proxy_set_server (ip4_address_t *addr, ip4_address_t *src_address,
 805                            u32 fib_id, int insert_option_82, int is_del)
 806 {
 807   return dhcp_proxy_set_server_2 (addr, src_address, 0 /* rx_fib_id */,
 808                                   fib_id /* server_fib_id */,
 809                                   insert_option_82, is_del);
 810 }
 811
 812
 813 static clib_error_t *
 814 dhcp_proxy_set_command_fn (vlib_main_t * vm,
 815                            unformat_input_t * input,
 816                            vlib_cli_command_t * cmd)
 817 {
 818   ip4_address_t server_addr, src_addr;
 819   u32 server_fib_id = 0, rx_fib_id = 0;
 820   int is_del = 0;
 821   int add_option_82 = 0;
 822   int set_src = 0, set_server = 0;
 823
 824   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
 825     {
 826       if (unformat (input, "server %U",
 827                     unformat_ip4_address, &server_addr))
 828         set_server = 1;
 829       else if (unformat (input, "server-fib-id %d", &server_fib_id))
 830         ;
 831       else if (unformat (input, "rx-fib-id %d", &rx_fib_id))
 832         ;
 833       else if (unformat(input, "src-address %U",
 834                         unformat_ip4_address, &src_addr))
 835         set_src = 1;
 836       else if (unformat (input, "add-option-82")
 837                || unformat (input, "insert-option-82"))
 838         add_option_82 = 1;
 839       else if (unformat (input, "delete") ||
 840                unformat (input, "del"))
 841         is_del = 1;
 842       else
 843         break;
 844     }
 845
 846   if (is_del || (set_server && set_src))
 847     {
 848       int rv;
 849
 850       rv = dhcp_proxy_set_server_2 (&server_addr, &src_addr, rx_fib_id,
 851                                     server_fib_id, add_option_82, is_del);
 852       switch (rv)
 853         {
 854         case 0:
 855           return 0;
 856
 857         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 858           return clib_error_return (0, "Invalid server address");
 859
 860         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 861           return clib_error_return (0, "Invalid src address");
 862
 863         case VNET_API_ERROR_NO_SUCH_INNER_FIB:
 864           return clib_error_return (0, "No such rx fib id %d", rx_fib_id);
 865
 866         case VNET_API_ERROR_NO_SUCH_FIB:
 867           return clib_error_return (0, "No such server fib id %d",
 868                                     server_fib_id);
 869
 870         case VNET_API_ERROR_NO_SUCH_ENTRY:
 871           return clib_error_return
 872             (0, "Fib id %d: no per-fib DHCP server configured", rx_fib_id);
 873
 874         default:
 875           return clib_error_return (0, "BUG: rv %d", rv);
 876         }
 877     }
 878   else
 879     return clib_error_return (0, "parse error`%U'",
 880                               format_unformat_error, input);
 881 }
 882
 883 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 884   .path = "set dhcp proxy",
 885   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [add-option-82] [server-fib-id <n>] [rx-fib-id <n>]",
 886   .function = dhcp_proxy_set_command_fn,
 887 };
 888
 889 u8 * format_dhcp_proxy_server (u8 * s, va_list * args)
 890 {
 891   dhcp_proxy_main_t * dm = va_arg (*args, dhcp_proxy_main_t *);
 892   dhcp_server_t * server = va_arg (*args, dhcp_server_t *);
 893   u32 rx_fib_index = va_arg (*args, u32);
 894   ip4_fib_t * rx_fib, * server_fib;
 895   u32 server_fib_id = ~0, rx_fib_id = ~0;
 896
 897   if (dm == 0)
 898     {
 899       s = format (s, "%=16s%=16s%=14s%=14s%=20s", "Server", "Src Address",
 900                   "Server FIB", "RX FIB", "Insert Option 82");
 901       return s;
 902     }
 903
 904   server_fib = find_ip4_fib_by_table_index_or_id
 905     (&ip4_main, server->server_fib_index, IP4_ROUTE_FLAG_FIB_INDEX);
 906
 907   if (server_fib)
 908     server_fib_id = server_fib->table_id;
 909
 910   rx_fib = find_ip4_fib_by_table_index_or_id
 911     (&ip4_main, rx_fib_index, IP4_ROUTE_FLAG_FIB_INDEX);
 912
 913   if (rx_fib)
 914     rx_fib_id = rx_fib->table_id;
 915
 916   s = format (s, "%=16U%=16U%=14u%=14u%=20s",
 917               format_ip4_address, &server->dhcp_server,
 918               format_ip4_address, &server->dhcp_src_address,
 919               server_fib_id, rx_fib_id,
 920               server->insert_option_82 ? "yes" : "no");
 921   return s;
 922 }
 923
 924 static clib_error_t *
 925 dhcp_proxy_show_command_fn (vlib_main_t * vm,
 926                             unformat_input_t * input,
 927                             vlib_cli_command_t * cmd)
 928 {
 929   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 930   ip4_main_t * im = &ip4_main;
 931   dhcp_server_t * server;
 932   u32 server_index;
 933   int i;
 934
 935   vlib_cli_output (vm, "%U", format_dhcp_proxy_server, 0 /* header line */,
 936                    0, 0);
 937
 938   for (i = 0; i < vec_len (im->fibs); i++)
 939     {
 940       if (i < vec_len(dpm->dhcp_server_index_by_rx_fib_index))
 941         server_index = dpm->dhcp_server_index_by_rx_fib_index[i];
 942       else
 943         server_index = 0;
 944       server = pool_elt_at_index (dpm->dhcp_servers, server_index);
 945       if (server->valid)
 946         vlib_cli_output (vm, "%U", format_dhcp_proxy_server, dpm,
 947                          server, i);
 948     }
 949
 950   return 0;
 951 }
 952
 953 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 954   .path = "show dhcp proxy",
 955   .short_help = "Display dhcp proxy server info",
 956   .function = dhcp_proxy_show_command_fn,
 957 };
 958
 959
 960 int dhcp_proxy_set_option82_vss(  u32 vrf_id,
 961                                   u32 oui,
 962                                   u32 fib_id,
 963                                   int is_del)
 964 {
 965   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 966   uword *p;
 967   vss_info *a;
 968   u32 old_oui=0, old_fib_id=0;
 969
 970   p = hash_get (dm->opt82vss_index_by_vrf_id, vrf_id);
 971
 972   if (p)
 973     {
 974       a = pool_elt_at_index (dm->opt82vss, p[0]);
 975       if (!a)
 976         return VNET_API_ERROR_NO_SUCH_FIB;
 977       old_oui = a->vpn_id.oui;
 978       old_fib_id = a->vpn_id.fib_id;
 979
 980       if (is_del)
 981         {
 982           if (old_oui == oui &&
 983               old_fib_id == fib_id)
 984             {
 985               pool_put(dm->opt82vss, a);
 986               hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
 987               return 0;
 988             }
 989           else
 990             return VNET_API_ERROR_NO_SUCH_ENTRY;
 991         }
 992       pool_put(dm->opt82vss, a);
 993       hash_unset (dm->opt82vss_index_by_vrf_id, vrf_id);
 994   } else if (is_del)
 995     return VNET_API_ERROR_NO_SUCH_ENTRY;
 996   pool_get (dm->opt82vss, a);
 997   memset (a, ~0, sizeof (a[0]));
 998   a->vpn_id.oui = oui;
 999   a->vpn_id.fib_id = fib_id;
1000   hash_set (dm->opt82vss_index_by_vrf_id, vrf_id, a - dm->opt82vss);
1001
1002   return 0;
1003 }
1004
1005 static clib_error_t *
1006 dhcp_option_82_vss_fn (vlib_main_t * vm,
1007                         unformat_input_t * input,
1008                         vlib_cli_command_t * cmd)
1009 {
1010   int is_del = 0, got_new_vpn_id=0;
1011   u32 oui=0, fib_id=0, tbl_id=~0;
1012
1013
1014   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
1015     {
1016
1017       if (unformat(input, "delete") || unformat(input, "del"))
1018           is_del = 1;
1019       else if (unformat (input, "oui %d", &oui))
1020           got_new_vpn_id = 1;
1021       else if (unformat (input, "vpn-id %d", &fib_id))
1022           got_new_vpn_id = 1;
1023       else if (unformat (input, "table %d", &tbl_id))
1024           got_new_vpn_id = 1;
1025       else
1026           break;
1027   }
1028   if (tbl_id == ~0)
1029       return clib_error_return (0, "no table ID specified.");
1030
1031   if (is_del || got_new_vpn_id)
1032     {
1033       int rv;
1034       rv = dhcp_proxy_set_option82_vss(tbl_id, oui, fib_id, is_del);
1035       switch (rv)
1036         {
1037         case 0:
1038             return 0;
1039
1040         case VNET_API_ERROR_NO_SUCH_FIB:
1041             return clib_error_return (0, "option 82 vss(oui:%d, vpn-id:%d) not found in table %d",
1042                                       oui, fib_id, tbl_id);
1043
1044         case VNET_API_ERROR_NO_SUCH_ENTRY:
1045             return clib_error_return (0, "option 82 vss for table %d not found in in pool.",
1046                                       tbl_id);
1047         default:
1048           return clib_error_return (0, "BUG: rv %d", rv);
1049         }
1050     }
1051   else
1052       return clib_error_return (0, "parse error`%U'",
1053                                 format_unformat_error, input);
1054 }
1055
1056 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
1057   .path = "set dhcp option-82 vss",
1058   .short_help = "set dhcp option-82 vss [del] table <table id> oui <oui> vpn-id <vpn-id>",
1059   .function = dhcp_option_82_vss_fn,
1060 };
1061
1062
1063 static clib_error_t *
1064 dhcp_vss_show_command_fn (vlib_main_t * vm,
1065                           unformat_input_t * input,
1066                           vlib_cli_command_t * cmd)
1067
1068 {
1069   dhcp_proxy_main_t * dm = &dhcp_proxy_main;
1070   vss_info *v;
1071   u32 oui;
1072   u32 fib_id;
1073   u32 tbl_id;
1074   uword index;
1075
1076   vlib_cli_output (vm, "%=9s%=11s%=12s","Table", "OUI", "VPN-ID");
1077   hash_foreach (tbl_id, index, dm->opt82vss_index_by_vrf_id,
1078   ({
1079      v = pool_elt_at_index (dm->opt82vss, index);
1080      oui = v->vpn_id.oui;
1081      fib_id = v->vpn_id.fib_id;
1082      vlib_cli_output (vm, "%=9d 0x%08x%=12d",
1083                       tbl_id, oui, fib_id);
1084   }));
1085
1086   return 0;
1087 }
1088
1089 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1090   .path = "show dhcp vss",
1091   .short_help = "show dhcp VSS",
1092   .function = dhcp_vss_show_command_fn,
1093 };
1094
1095 static clib_error_t *
1096 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1097                                 unformat_input_t * input,
1098                                 vlib_cli_command_t * cmd)
1099
1100 {
1101   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
1102   vnet_main_t *vnm = vnet_get_main();
1103   u32 sw_if_index0=0, sw_if_index;
1104   ip4_address_t *ia0;
1105   vnet_sw_interface_t *swif;
1106
1107   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
1108     {
1109
1110       if (unformat(input, "%U",
1111                    unformat_vnet_sw_interface, dm->vnet_main, &sw_if_index0))
1112         {
1113           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1114           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1115             swif->unnumbered_sw_if_index : sw_if_index0;
1116           ia0 = ip4_interface_first_address(&ip4_main, sw_if_index);
1117           if (ia0)
1118             {
1119               vlib_cli_output (vm, "%=20s%=20s", "interface",
1120                                "source IP address");
1121
1122               vlib_cli_output (vm, "%=20U%=20U",
1123                                format_vnet_sw_if_index_name,
1124                                dm->vnet_main, sw_if_index0,
1125                                format_ip4_address, ia0);
1126             }
1127           else
1128             vlib_cli_output (vm, "%=34s %=20U",
1129                              "No IPv4 address configured on",
1130                              format_vnet_sw_if_index_name,
1131                              dm->vnet_main, sw_if_index);
1132         }
1133       else
1134         break;
1135     }
1136
1137   return 0;
1138 }
1139
1140 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1141   .path = "show dhcp option-82-address interface",
1142   .short_help = "show dhcp option-82-address interface <interface>",
1143   .function = dhcp_option_82_address_show_command_fn,
1144 };