src/vnet/dhcp/dhcp4_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/dhcp_proxy.h>
  21 #include <vnet/dhcp/client.h>
  22 #include <vnet/fib/ip4_fib.h>
  23
  24 static char * dhcp_proxy_error_strings[] = {
  25 #define dhcp_proxy_error(n,s) s,
  26 #include <vnet/dhcp/dhcp4_proxy_error.def>
  27 #undef dhcp_proxy_error
  28 };
  29
  30 #define foreach_dhcp_proxy_to_server_input_next \
  31   _ (DROP, "error-drop")                        \
  32   _ (LOOKUP, "ip4-lookup")                      \
  33   _ (SEND_TO_CLIENT, "dhcp-proxy-to-client")
  34
  35 typedef enum {
  36 #define _(s,n) DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s,
  37   foreach_dhcp_proxy_to_server_input_next
  38 #undef _
  39   DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
  40 } dhcp_proxy_to_server_input_next_t;
  41
  42 typedef struct {
  43   /* 0 => to server, 1 => to client */
  44   int which;
  45   ip4_address_t trace_ip4_address;
  46   u32 error;
  47   u32 sw_if_index;
  48   u32 original_sw_if_index;
  49 } dhcp_proxy_trace_t;
  50
  51 #define VPP_DHCP_OPTION82_SUB1_SIZE   6
  52 #define VPP_DHCP_OPTION82_SUB5_SIZE   6
  53 #define VPP_DHCP_OPTION82_VSS_SIZE    12
  54 #define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
  55                                 VPP_DHCP_OPTION82_SUB5_SIZE + \
  56                                 VPP_DHCP_OPTION82_VSS_SIZE +3)
  57
  58 static vlib_node_registration_t dhcp_proxy_to_server_node;
  59 static vlib_node_registration_t dhcp_proxy_to_client_node;
  60
  61 static u8 *
  62 format_dhcp_proxy_trace (u8 * s, va_list * args)
  63 {
  64   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  65   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  66   dhcp_proxy_trace_t * t = va_arg (*args, dhcp_proxy_trace_t *);
  67
  68   if (t->which == 0)
  69     s = format (s, "DHCP proxy: sent to server %U\n",
  70                 format_ip4_address, &t->trace_ip4_address, t->error);
  71   else
  72     s = format (s, "DHCP proxy: broadcast to client from %U\n",
  73                 format_ip4_address, &t->trace_ip4_address);
  74
  75   if (t->error != (u32)~0)
  76     s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
  77
  78   s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
  79               t->original_sw_if_index, t->sw_if_index);
  80
  81   return s;
  82 }
  83
  84 static u8 *
  85 format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
  86 {
  87   dhcp_header_t * h = va_arg (*args, dhcp_header_t *);
  88   u32 max_header_bytes = va_arg (*args, u32);
  89   u32 header_bytes;
  90
  91   header_bytes = sizeof (h[0]);
  92   if (max_header_bytes != 0 && header_bytes > max_header_bytes)
  93     return format (s, "dhcp header truncated");
  94
  95   s = format (s, "DHCP Proxy");
  96
  97   return s;
  98 }
  99
 100 static uword
 101 dhcp_proxy_to_server_input (vlib_main_t * vm,
 102                             vlib_node_runtime_t * node,
 103                             vlib_frame_t * from_frame)
 104 {
 105   u32 n_left_from, next_index, * from, * to_next;
 106   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 107   from = vlib_frame_vector_args (from_frame);
 108   n_left_from = from_frame->n_vectors;
 109   u32 pkts_to_server=0, pkts_to_client=0, pkts_no_server=0;
 110   u32 pkts_no_interface_address=0;
 111   u32 pkts_too_big=0;
 112   ip4_main_t * im = &ip4_main;
 113
 114   next_index = node->cached_next_index;
 115
 116   while (n_left_from > 0)
 117     {
 118       u32 n_left_to_next;
 119
 120       vlib_get_next_frame (vm, node, next_index,
 121                            to_next, n_left_to_next);
 122
 123       while (n_left_from > 0 && n_left_to_next > 0)
 124         {
 125           u32 bi0;
 126           vlib_buffer_t * b0;
 127           udp_header_t * u0;
 128           dhcp_header_t * h0;
 129           ip4_header_t * ip0;
 130           u32 next0;
 131           u32 old0, new0;
 132           ip_csum_t sum0;
 133           u32 error0 = (u32) ~0;
 134           u32 sw_if_index = 0;
 135           u32 original_sw_if_index = 0;
 136           u8  *end = NULL;
 137           u32 fib_index;
 138           dhcp_proxy_t *proxy;
 139           dhcp_server_t *server;
 140           u32 rx_sw_if_index;
 141           dhcp_option_t *o;
 142           u32 len = 0;
 143           vlib_buffer_free_list_t *fl;
 144           u8 is_discover = 0;
 145
 146           bi0 = from[0];
 147           from += 1;
 148           n_left_from -= 1;
 149
 150           b0 = vlib_get_buffer (vm, bi0);
 151
 152           h0 = vlib_buffer_get_current (b0);
 153
 154           /*
 155            * udp_local hands us the DHCP header, need udp hdr,
 156            * ip hdr to relay to server
 157            */
 158           vlib_buffer_advance (b0, -(sizeof(*u0)));
 159           u0 = vlib_buffer_get_current (b0);
 160
 161           /* This blows. Return traffic has src_port = 67, dst_port = 67 */
 162           if (u0->src_port == clib_net_to_host_u16(UDP_DST_PORT_dhcp_to_server))
 163             {
 164               vlib_buffer_advance (b0, sizeof(*u0));
 165               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
 166               error0 = 0;
 167               pkts_to_client++;
 168               goto do_enqueue;
 169             }
 170
 171           rx_sw_if_index = vnet_buffer(b0)->sw_if_index[VLIB_RX];
 172
 173           fib_index = im->fib_index_by_sw_if_index [rx_sw_if_index];
 174           proxy = dhcp_get_proxy(dpm, fib_index, FIB_PROTOCOL_IP4);
 175
 176           if (PREDICT_FALSE (NULL == proxy))
 177             {
 178               error0 = DHCP_PROXY_ERROR_NO_SERVER;
 179               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 180               pkts_no_server++;
 181               goto do_trace;
 182             }
 183
 184           server = &proxy->dhcp_servers[0];
 185           vlib_buffer_advance (b0, -(sizeof(*ip0)));
 186           ip0 = vlib_buffer_get_current (b0);
 187
 188           /* disable UDP checksum */
 189           u0->checksum = 0;
 190           sum0 = ip0->checksum;
 191           old0 = ip0->dst_address.as_u32;
 192           new0 = server->dhcp_server.ip4.as_u32;
 193           ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 194           sum0 = ip_csum_update (sum0, old0, new0,
 195                                 ip4_header_t /* structure */,
 196                                 dst_address /* changed member */);
 197           ip0->checksum = ip_csum_fold (sum0);
 198
 199           sum0 = ip0->checksum;
 200           old0 = ip0->src_address.as_u32;
 201           new0 = proxy->dhcp_src_address.ip4.as_u32;
 202           ip0->src_address.as_u32 = new0;
 203           sum0 = ip_csum_update (sum0, old0, new0,
 204                                 ip4_header_t /* structure */,
 205                                 src_address /* changed member */);
 206           ip0->checksum = ip_csum_fold (sum0);
 207
 208           /* Send to DHCP server via the configured FIB */
 209           vnet_buffer(b0)->sw_if_index[VLIB_TX] =
 210             server->server_fib_index;
 211
 212           h0->gateway_ip_address.as_u32 = proxy->dhcp_src_address.ip4.as_u32;
 213           pkts_to_server++;
 214
 215           o = (dhcp_option_t *) h0->options;
 216
 217           fib_index = im->fib_index_by_sw_if_index
 218               [vnet_buffer(b0)->sw_if_index[VLIB_RX]];
 219
 220           end = b0->data + b0->current_data + b0->current_length;
 221           /* TLVs are not performance-friendly... */
 222           while  (o->option != 0xFF /* end of options */ && (u8 *)o < end)
 223             {
 224               if (DHCP_PACKET_OPTION_MSG_TYPE == o->option)
 225                 {
 226                   if (DHCP_PACKET_DISCOVER == o->data[0])
 227                     {
 228                       is_discover = 1;
 229                     }
 230                 }
 231               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 232           }
 233
 234           fl = vlib_buffer_get_free_list (vm, vlib_buffer_get_free_list_index (b0));
 235           // start write at (option*)o, some packets have padding
 236           if (((u8 *)o - (u8 *)b0->data + VPP_DHCP_OPTION82_SIZE) > fl->n_data_bytes)
 237           {
 238               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 239               pkts_too_big++;
 240               goto do_trace;
 241           }
 242
 243           if ((o->option == 0xFF)  && ((u8 *)o <= end))
 244           {
 245               vnet_main_t *vnm = vnet_get_main();
 246               u16 old_l0, new_l0;
 247               ip4_address_t _ia0, * ia0 = &_ia0;
 248               dhcp_vss_t *vss;
 249               vnet_sw_interface_t *swif;
 250               sw_if_index = 0;
 251               original_sw_if_index = 0;
 252
 253               original_sw_if_index = sw_if_index =
 254                   vnet_buffer(b0)->sw_if_index[VLIB_RX];
 255               swif = vnet_get_sw_interface (vnm, sw_if_index);
 256               if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 257                   sw_if_index = swif->unnumbered_sw_if_index;
 258
 259               /*
 260                * Get the first ip4 address on the [client-side]
 261                * RX interface, if not unnumbered. otherwise use
 262                * the loopback interface's ip address.
 263                */
 264               ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
 265
 266               if (ia0 == 0)
 267               {
 268                   error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 269                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 270                   pkts_no_interface_address++;
 271                   goto do_trace;
 272               }
 273
 274               /* Add option 82 */
 275               o->option = 82;   /* option 82 */
 276               o->length = 12;   /* 12 octets to follow */
 277               o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
 278               o->data[1] = 4;   /* length of suboption */
 279               o->data[2] = (original_sw_if_index >> 24) & 0xFF;
 280               o->data[3] = (original_sw_if_index >> 16) & 0xFF;
 281               o->data[4] = (original_sw_if_index >> 8)  & 0xFF;
 282               o->data[5] = (original_sw_if_index >> 0)  & 0xFF;
 283               o->data[6] = 5; /* suboption 5 (client RX intfc address) */
 284               o->data[7] = 4; /* length 4 */
 285               o->data[8] = ia0->as_u8[0];
 286               o->data[9] = ia0->as_u8[1];
 287               o->data[10] = ia0->as_u8[2];
 288               o->data[11] = ia0->as_u8[3];
 289               o->data[12] = 0xFF;
 290
 291               vss = dhcp_get_vss_info (dpm, fib_index, FIB_PROTOCOL_IP4);
 292               if (NULL != vss)
 293               {
 294                   u32 opt82_fib_id=0, opt82_oui=0;
 295
 296                   opt82_oui =  vss->oui;
 297                   opt82_fib_id =  vss->fib_id;
 298
 299                   o->data[12] = 151; /* vss suboption */
 300                   if (255 == opt82_fib_id) {
 301                       o->data[13] = 1;   /* length */
 302                       o->data[14] = 255;   /* vss option type */
 303                       o->data[15] = 152; /* vss control suboption */
 304                       o->data[16] = 0;   /* length */
 305                       /* and a new "end-of-options" option (0xff) */
 306                       o->data[17] = 0xFF;
 307                       o->length += 5;
 308                   } else {
 309                       o->data[13] = 8;   /* length */
 310                       o->data[14] = 1;   /* vss option type */
 311                       o->data[15] = (opt82_oui >> 16) & 0xff;
 312                       o->data[16] = (opt82_oui >> 8) & 0xff;
 313                       o->data[17] = (opt82_oui ) & 0xff;
 314                       o->data[18] = (opt82_fib_id >> 24) & 0xff;
 315                       o->data[19] = (opt82_fib_id >> 16) & 0xff;
 316                       o->data[20] = (opt82_fib_id >> 8) & 0xff;
 317                       o->data[21] = (opt82_fib_id) & 0xff;
 318                       o->data[22] = 152; /* vss control suboption */
 319                       o->data[23] = 0;   /* length */
 320
 321                       /* and a new "end-of-options" option (0xff) */
 322                       o->data[24] = 0xFF;
 323                       o->length += 12;
 324                   }
 325               }
 326
 327               len = o->length + 3;
 328               b0->current_length += len;
 329               /* Fix IP header length and checksum */
 330               old_l0 = ip0->length;
 331               new_l0 = clib_net_to_host_u16 (old_l0);
 332               new_l0 += len;
 333               new_l0 = clib_host_to_net_u16 (new_l0);
 334               ip0->length = new_l0;
 335               sum0 = ip0->checksum;
 336               sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 337                                      length /* changed member */);
 338               ip0->checksum = ip_csum_fold (sum0);
 339
 340               /* Fix UDP length */
 341               new_l0 = clib_net_to_host_u16 (u0->length);
 342               new_l0 += len;
 343               u0->length = clib_host_to_net_u16 (new_l0);
 344           } else {
 345               vlib_node_increment_counter
 346                   (vm, dhcp_proxy_to_server_node.index,
 347                    DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
 348           }
 349
 350           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
 351
 352           /*
 353            * If we have multiple servers configured and this is the
 354            * client's discover message, then send copies to each of
 355            * those servers
 356            */
 357           if (is_discover && vec_len(proxy->dhcp_servers) > 1)
 358           {
 359               u32 ii;
 360
 361               for (ii = 1; ii < vec_len(proxy->dhcp_servers); ii++)
 362               {
 363                   vlib_buffer_t *c0;
 364                   u32 ci0;
 365
 366                   c0 = vlib_buffer_copy(vm, b0);
 367                   ci0 = vlib_get_buffer_index(vm, c0);
 368                   server = &proxy->dhcp_servers[ii];
 369
 370                   ip0 = vlib_buffer_get_current (c0);
 371
 372                   sum0 = ip0->checksum;
 373                   old0 = ip0->dst_address.as_u32;
 374                   new0 = server->dhcp_server.ip4.as_u32;
 375                   ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 376                   sum0 = ip_csum_update (sum0, old0, new0,
 377                                          ip4_header_t /* structure */,
 378                                          dst_address /* changed member */);
 379                   ip0->checksum = ip_csum_fold (sum0);
 380
 381                   to_next[0] = ci0;
 382                   to_next += 1;
 383                   n_left_to_next -= 1;
 384
 385                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 386                                                    to_next, n_left_to_next,
 387                                                    ci0, next0);
 388
 389                   if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 390                   {
 391                       dhcp_proxy_trace_t *tr;
 392
 393                       tr = vlib_add_trace (vm, node, c0, sizeof (*tr));
 394                       tr->which = 0; /* to server */
 395                       tr->error = error0;
 396                       tr->original_sw_if_index = original_sw_if_index;
 397                       tr->sw_if_index = sw_if_index;
 398                       if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 399                           tr->trace_ip4_address.as_u32 = server->dhcp_server.ip4.as_u32;
 400                   }
 401
 402                   if (PREDICT_FALSE(0 == n_left_to_next))
 403                   {
 404                       vlib_put_next_frame (vm, node, next_index,
 405                                            n_left_to_next);
 406                       vlib_get_next_frame (vm, node, next_index,
 407                                            to_next, n_left_to_next);
 408                   }
 409               }
 410           }
 411         do_trace:
 412           if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 413             {
 414                dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 415                                                         b0, sizeof (*tr));
 416                tr->which = 0; /* to server */
 417                tr->error = error0;
 418                tr->original_sw_if_index = original_sw_if_index;
 419                tr->sw_if_index = sw_if_index;
 420                if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 421                  tr->trace_ip4_address.as_u32 =
 422                      proxy->dhcp_servers[0].dhcp_server.ip4.as_u32;
 423             }
 424
 425         do_enqueue:
 426           to_next[0] = bi0;
 427           to_next += 1;
 428           n_left_to_next -= 1;
 429
 430           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 431                                            to_next, n_left_to_next,
 432                                            bi0, next0);
 433         }
 434
 435       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 436     }
 437
 438   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 439                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
 440                                pkts_to_client);
 441   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 442                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
 443                                pkts_to_server);
 444   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 445                                DHCP_PROXY_ERROR_NO_SERVER,
 446                                pkts_no_server);
 447   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 448                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
 449                                pkts_no_interface_address);
 450  vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 451                               DHCP_PROXY_ERROR_PKT_TOO_BIG,
 452                               pkts_too_big);
 453   return from_frame->n_vectors;
 454 }
 455
 456 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node, static) = {
 457   .function = dhcp_proxy_to_server_input,
 458   .name = "dhcp-proxy-to-server",
 459   /* Takes a vector of packets. */
 460   .vector_size = sizeof (u32),
 461
 462   .n_errors = DHCP_PROXY_N_ERROR,
 463   .error_strings = dhcp_proxy_error_strings,
 464
 465   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
 466   .next_nodes = {
 467 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
 468     foreach_dhcp_proxy_to_server_input_next
 469 #undef _
 470   },
 471
 472   .format_buffer = format_dhcp_proxy_header_with_length,
 473   .format_trace = format_dhcp_proxy_trace,
 474 #if 0
 475   .unformat_buffer = unformat_dhcp_proxy_header,
 476 #endif
 477 };
 478
 479 static uword
 480 dhcp_proxy_to_client_input (vlib_main_t * vm,
 481                             vlib_node_runtime_t * node,
 482                             vlib_frame_t * from_frame)
 483 {
 484   u32 n_left_from, * from;
 485   ethernet_main_t *em = ethernet_get_main (vm);
 486   dhcp_proxy_main_t * dpm = &dhcp_proxy_main;
 487   vnet_main_t * vnm = vnet_get_main();
 488   ip4_main_t * im = &ip4_main;
 489
 490   from = vlib_frame_vector_args (from_frame);
 491   n_left_from = from_frame->n_vectors;
 492
 493   while (n_left_from > 0)
 494     {
 495       u32 bi0;
 496       vlib_buffer_t * b0;
 497       udp_header_t * u0;
 498       dhcp_header_t * h0;
 499       ip4_header_t * ip0 = 0;
 500       ip4_address_t * ia0 = 0;
 501       u32 old0, new0;
 502       ip_csum_t sum0;
 503       ethernet_interface_t *ei0;
 504       ethernet_header_t *mac0;
 505       vnet_hw_interface_t *hi0;
 506       vlib_frame_t *f0;
 507       u32 * to_next0;
 508       u32 sw_if_index = ~0;
 509       vnet_sw_interface_t *si0;
 510       u32 error0 = (u32)~0;
 511       vnet_sw_interface_t *swif;
 512       u32 fib_index;
 513       dhcp_proxy_t *proxy;
 514       dhcp_server_t *server;
 515       u32 original_sw_if_index = (u32) ~0;
 516       ip4_address_t relay_addr = {
 517           .as_u32 = 0,
 518       };
 519
 520       bi0 = from[0];
 521       from += 1;
 522       n_left_from -= 1;
 523
 524       b0 = vlib_get_buffer (vm, bi0);
 525       h0 = vlib_buffer_get_current (b0);
 526
 527       /*
 528        * udp_local hands us the DHCP header, need udp hdr,
 529        * ip hdr to relay to client
 530        */
 531       vlib_buffer_advance (b0, -(sizeof(*u0)));
 532       u0 = vlib_buffer_get_current (b0);
 533
 534       vlib_buffer_advance (b0, -(sizeof(*ip0)));
 535       ip0 = vlib_buffer_get_current (b0);
 536
 537       /* Consumed by dhcp client code? */
 538       if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
 539           continue;
 540
 541       if (1 /* dpm->insert_option_82 */)
 542         {
 543           dhcp_option_t *o = (dhcp_option_t *) h0->options;
 544           dhcp_option_t *sub;
 545
 546           /* Parse through TLVs looking for option 82.
 547              The circuit-ID is the FIB number we need
 548              to track down the client-facing interface */
 549
 550           while (o->option != 0xFF /* end of options */ &&
 551                  (u8 *) o < (b0->data + b0->current_data + b0->current_length))
 552             {
 553               if (o->option == 82)
 554                 {
 555                     u32 vss_exist = 0;
 556                     u32 vss_ctrl = 0;
 557                     sub = (dhcp_option_t *) &o->data[0];
 558                     while (sub->option != 0xFF /* end of options */ &&
 559                            (u8 *) sub < (u8 *)(o + o->length)) {
 560                         /* If this is one of ours, it will have
 561                            total length 12, circuit-id suboption type,
 562                            and the sw_if_index */
 563                         if (sub->option == 1 && sub->length == 4)
 564                           {
 565                             sw_if_index = ((sub->data[0] << 24) |
 566                                            (sub->data[1] << 16) |
 567                                            (sub->data[2] << 8)  |
 568                                            (sub->data[3]));
 569                           }
 570                         else if (sub->option == 5 && sub->length == 4)
 571                           {
 572                               relay_addr.as_u8[0] = sub->data[0];
 573                               relay_addr.as_u8[1] = sub->data[1];
 574                               relay_addr.as_u8[2] = sub->data[2];
 575                               relay_addr.as_u8[3] = sub->data[3];
 576                           }
 577                         else if (sub->option == 151 &&
 578                                  sub->length == 7 &&
 579                                  sub->data[0] == 1)
 580                             vss_exist = 1;
 581                         else if (sub->option == 152 && sub->length == 0)
 582                             vss_ctrl = 1;
 583                         sub = (dhcp_option_t *)
 584                           (((uword) sub) + (sub->length + 2));
 585                     }
 586                     if (vss_ctrl && vss_exist)
 587                       vlib_node_increment_counter
 588                         (vm, dhcp_proxy_to_client_node.index,
 589                          DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 590
 591                 }
 592               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 593             }
 594         }
 595
 596       if (sw_if_index == (u32)~0)
 597         {
 598           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 599
 600         drop_packet:
 601           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 602                                        error0, 1);
 603           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 604           to_next0 = vlib_frame_vector_args (f0);
 605           to_next0[0] = bi0;
 606           f0->n_vectors = 1;
 607           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 608           goto do_trace;
 609         }
 610
 611       if (relay_addr.as_u32 == 0)
 612         {
 613           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ADDR;
 614           goto drop_packet;
 615         }
 616
 617       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 618         {
 619           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ITF;
 620           goto drop_packet;
 621         }
 622
 623       fib_index = im->fib_index_by_sw_if_index [sw_if_index];
 624       proxy = dhcp_get_proxy(dpm, fib_index, FIB_PROTOCOL_IP4);
 625
 626       if (PREDICT_FALSE (NULL == proxy))
 627         {
 628           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 629           goto drop_packet;
 630         }
 631
 632       vec_foreach(server, proxy->dhcp_servers)
 633         {
 634           if (ip0->src_address.as_u32 == server->dhcp_server.ip4.as_u32)
 635             {
 636               goto server_found;
 637             }
 638         }
 639
 640       error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 641       goto drop_packet;
 642
 643     server_found:
 644       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 645
 646       swif = vnet_get_sw_interface (vnm, sw_if_index);
 647       original_sw_if_index = sw_if_index;
 648       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 649           sw_if_index = swif->unnumbered_sw_if_index;
 650
 651       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 652       if (ia0 == 0)
 653         {
 654           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 655           goto drop_packet;
 656         }
 657
 658       if (relay_addr.as_u32 != ia0->as_u32)
 659         {
 660           error0 = DHCP_PROXY_ERROR_BAD_YIADDR;
 661           goto drop_packet;
 662         }
 663
 664       u0->checksum = 0;
 665       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 666       sum0 = ip0->checksum;
 667       old0 = ip0->dst_address.as_u32;
 668       new0 = 0xFFFFFFFF;
 669       ip0->dst_address.as_u32 = new0;
 670       sum0 = ip_csum_update (sum0, old0, new0,
 671                             ip4_header_t /* structure */,
 672                             dst_address /* offset of changed member */);
 673       ip0->checksum = ip_csum_fold (sum0);
 674
 675       sum0 = ip0->checksum;
 676       old0 = ip0->src_address.as_u32;
 677       new0 = ia0->as_u32;
 678       ip0->src_address.as_u32 = new0;
 679       sum0 = ip_csum_update (sum0, old0, new0,
 680                             ip4_header_t /* structure */,
 681                             src_address /* offset of changed member */);
 682       ip0->checksum = ip_csum_fold (sum0);
 683
 684       vlib_buffer_advance (b0, -(sizeof(ethernet_header_t)));
 685       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 686       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 687           vlib_buffer_advance (b0, -4 /* space for VLAN tag */);
 688
 689       mac0 = vlib_buffer_get_current (b0);
 690
 691       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 692       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 693       clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 694       memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 695       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 696         clib_net_to_host_u16(0x8100) : clib_net_to_host_u16 (0x0800);
 697
 698       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 699         {
 700           u32 * vlan_tag = (u32 *)(mac0+1);
 701           u32 tmp;
 702           tmp = (si0->sub.id << 16) | 0x0800;
 703           *vlan_tag = clib_host_to_net_u32 (tmp);
 704         }
 705
 706       /* $$$ This needs to be rewritten, for sure */
 707       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 708       to_next0 = vlib_frame_vector_args (f0);
 709       to_next0[0] = bi0;
 710       f0->n_vectors = 1;
 711       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 712
 713     do_trace:
 714       if (PREDICT_FALSE(b0->flags & VLIB_BUFFER_IS_TRACED))
 715         {
 716           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 717                                                    b0, sizeof (*tr));
 718           tr->which = 1; /* to client */
 719           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 720           tr->error = error0;
 721           tr->original_sw_if_index = original_sw_if_index;
 722           tr->sw_if_index = sw_if_index;
 723         }
 724     }
 725   return from_frame->n_vectors;
 726 }
 727
 728 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node, static) = {
 729   .function = dhcp_proxy_to_client_input,
 730   .name = "dhcp-proxy-to-client",
 731   /* Takes a vector of packets. */
 732   .vector_size = sizeof (u32),
 733
 734   .n_errors = DHCP_PROXY_N_ERROR,
 735   .error_strings = dhcp_proxy_error_strings,
 736   .format_buffer = format_dhcp_proxy_header_with_length,
 737   .format_trace = format_dhcp_proxy_trace,
 738 #if 0
 739   .unformat_buffer = unformat_dhcp_proxy_header,
 740 #endif
 741 };
 742
 743 static clib_error_t *
 744 dhcp4_proxy_init (vlib_main_t * vm)
 745 {
 746   dhcp_proxy_main_t * dm = &dhcp_proxy_main;
 747   vlib_node_t * error_drop_node;
 748
 749   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 750   dm->error_drop_node_index = error_drop_node->index;
 751
 752   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
 753                          dhcp_proxy_to_client_node.index, 1 /* is_ip4 */);
 754
 755   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
 756                          dhcp_proxy_to_server_node.index, 1 /* is_ip4 */);
 757
 758   return 0;
 759 }
 760
 761
 762 VLIB_INIT_FUNCTION (dhcp4_proxy_init);
 763
 764 int
 765 dhcp4_proxy_set_server (ip46_address_t *addr,
 766                         ip46_address_t *src_addr,
 767                         u32 rx_table_id,
 768                         u32 server_table_id,
 769                         int is_del)
 770 {
 771   u32 rx_fib_index = 0;
 772   int rc = 0;
 773
 774   const fib_prefix_t all_1s =
 775   {
 776       .fp_len = 32,
 777       .fp_addr.ip4.as_u32 = 0xffffffff,
 778       .fp_proto = FIB_PROTOCOL_IP4,
 779   };
 780
 781   if (ip46_address_is_zero(addr))
 782     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 783
 784   if (ip46_address_is_zero(src_addr))
 785     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 786
 787   rx_fib_index = fib_table_find_or_create_and_lock(FIB_PROTOCOL_IP4,
 788                                                    rx_table_id,
 789                                                    FIB_SOURCE_DHCP);
 790
 791   if (is_del)
 792     {
 793       if (dhcp_proxy_server_del (FIB_PROTOCOL_IP4, rx_fib_index,
 794                                  addr, server_table_id))
 795       {
 796           fib_table_entry_special_remove(rx_fib_index,
 797                                          &all_1s,
 798                                          FIB_SOURCE_DHCP);
 799           fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 800       }
 801     }
 802   else
 803   {
 804       if (dhcp_proxy_server_add (FIB_PROTOCOL_IP4,
 805                                  addr, src_addr,
 806                                  rx_fib_index, server_table_id))
 807       {
 808           fib_table_entry_special_add(rx_fib_index,
 809                                       &all_1s,
 810                                       FIB_SOURCE_DHCP,
 811                                       FIB_ENTRY_FLAG_LOCAL);
 812           fib_table_lock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 813       }
 814   }
 815   fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 816
 817   return (rc);
 818 }
 819
 820 static clib_error_t *
 821 dhcp4_proxy_set_command_fn (vlib_main_t * vm,
 822                             unformat_input_t * input,
 823                             vlib_cli_command_t * cmd)
 824 {
 825   ip46_address_t server_addr, src_addr;
 826   u32 server_table_id = 0, rx_table_id = 0;
 827   int is_del = 0;
 828   int set_src = 0, set_server = 0;
 829
 830   memset(&server_addr, 0, sizeof(server_addr));
 831   memset(&src_addr, 0, sizeof(src_addr));
 832
 833   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
 834     {
 835       if (unformat (input, "server %U",
 836                     unformat_ip4_address, &server_addr.ip4))
 837         set_server = 1;
 838       else if (unformat (input, "server-fib-id %d", &server_table_id))
 839         ;
 840       else if (unformat (input, "rx-fib-id %d", &rx_table_id))
 841         ;
 842       else if (unformat(input, "src-address %U",
 843                         unformat_ip4_address, &src_addr.ip4))
 844         set_src = 1;
 845       else if (unformat (input, "delete") ||
 846                unformat (input, "del"))
 847         is_del = 1;
 848       else
 849         break;
 850     }
 851
 852   if (is_del || (set_server && set_src))
 853     {
 854       int rv;
 855
 856       rv = dhcp4_proxy_set_server (&server_addr, &src_addr, rx_table_id,
 857                                    server_table_id, is_del);
 858       switch (rv)
 859         {
 860         case 0:
 861           return 0;
 862
 863         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 864           return clib_error_return (0, "Invalid server address");
 865
 866         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 867           return clib_error_return (0, "Invalid src address");
 868
 869         case VNET_API_ERROR_NO_SUCH_ENTRY:
 870           return clib_error_return
 871             (0, "Fib id %d: no per-fib DHCP server configured", rx_table_id);
 872
 873         default:
 874           return clib_error_return (0, "BUG: rv %d", rv);
 875         }
 876     }
 877   else
 878     return clib_error_return (0, "parse error`%U'",
 879                               format_unformat_error, input);
 880 }
 881
 882 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 883   .path = "set dhcp proxy",
 884   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [server-fib-id <n>] [rx-fib-id <n>]",
 885   .function = dhcp4_proxy_set_command_fn,
 886 };
 887
 888 static u8 *
 889 format_dhcp4_proxy_server (u8 * s, va_list * args)
 890 {
 891   dhcp_proxy_t *proxy = va_arg (*args, dhcp_proxy_t *);
 892   ip4_fib_t * rx_fib, * server_fib;
 893   dhcp_server_t *server;
 894
 895   if (proxy == 0)
 896     {
 897         s = format (s, "%=14s%=16s%s", "RX FIB", "Src Address",
 898                     "Servers FIB,Address");
 899       return s;
 900     }
 901
 902   rx_fib = ip4_fib_get(proxy->rx_fib_index);
 903
 904   s = format (s, "%=14u%=16U",
 905               rx_fib->table_id,
 906               format_ip46_address, &proxy->dhcp_src_address, IP46_TYPE_ANY);
 907
 908   vec_foreach(server, proxy->dhcp_servers)
 909   {
 910       server_fib = ip4_fib_get(server->server_fib_index);
 911       s = format (s, "%u,%U  ",
 912                   server_fib->table_id,
 913                   format_ip46_address, &server->dhcp_server, IP46_TYPE_ANY);
 914   }
 915   return s;
 916 }
 917
 918 static int
 919 dhcp4_proxy_show_walk (dhcp_proxy_t *server,
 920                        void *ctx)
 921 {
 922     vlib_main_t * vm = ctx;
 923
 924     vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, server);
 925
 926     return (1);
 927 }
 928
 929 static clib_error_t *
 930 dhcp4_proxy_show_command_fn (vlib_main_t * vm,
 931                              unformat_input_t * input,
 932                              vlib_cli_command_t * cmd)
 933 {
 934   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, NULL /* header line */);
 935
 936   dhcp_proxy_walk(FIB_PROTOCOL_IP4, dhcp4_proxy_show_walk, vm);
 937
 938   return (NULL);
 939 }
 940
 941 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 942   .path = "show dhcp proxy",
 943   .short_help = "Display dhcp proxy server info",
 944   .function = dhcp4_proxy_show_command_fn,
 945 };
 946
 947 static clib_error_t *
 948 dhcp_option_82_vss_fn (vlib_main_t * vm,
 949                         unformat_input_t * input,
 950                         vlib_cli_command_t * cmd)
 951 {
 952   int is_del = 0, got_new_vpn_id=0;
 953   u32 oui=0, fib_id=0, tbl_id=~0;
 954
 955   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
 956     {
 957
 958       if (unformat(input, "delete") || unformat(input, "del"))
 959           is_del = 1;
 960       else if (unformat (input, "oui %d", &oui))
 961           got_new_vpn_id = 1;
 962       else if (unformat (input, "vpn-id %d", &fib_id))
 963           got_new_vpn_id = 1;
 964       else if (unformat (input, "table %d", &tbl_id))
 965           got_new_vpn_id = 1;
 966       else
 967           break;
 968   }
 969   if (tbl_id == ~0)
 970       return clib_error_return (0, "no table ID specified.");
 971
 972   if (is_del || got_new_vpn_id)
 973     {
 974       int rv;
 975       rv = dhcp_proxy_set_vss(FIB_PROTOCOL_IP4, tbl_id, oui, fib_id, is_del);
 976       switch (rv)
 977         {
 978         case 0:
 979             return 0;
 980
 981         case VNET_API_ERROR_NO_SUCH_FIB:
 982             return clib_error_return (0, "option 82 vss(oui:%d, vpn-id:%d) not found in table %d",
 983                                       oui, fib_id, tbl_id);
 984
 985         case VNET_API_ERROR_NO_SUCH_ENTRY:
 986             return clib_error_return (0, "option 82 vss for table %d not found in in pool.",
 987                                       tbl_id);
 988         default:
 989           return clib_error_return (0, "BUG: rv %d", rv);
 990         }
 991     }
 992   else
 993       return clib_error_return (0, "parse error`%U'",
 994                                 format_unformat_error, input);
 995 }
 996
 997 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
 998   .path = "set dhcp option-82 vss",
 999   .short_help = "set dhcp option-82 vss [del] table <table id> oui <oui> vpn-id <vpn-id>",
1000   .function = dhcp_option_82_vss_fn,
1001 };
1002
1003 static clib_error_t *
1004 dhcp_vss_show_command_fn (vlib_main_t * vm,
1005                           unformat_input_t * input,
1006                           vlib_cli_command_t * cmd)
1007
1008 {
1009   dhcp_vss_walk(FIB_PROTOCOL_IP4, dhcp_vss_show_walk, vm);
1010
1011   return (NULL);
1012 }
1013
1014 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1015   .path = "show dhcp vss",
1016   .short_help = "show dhcp VSS",
1017   .function = dhcp_vss_show_command_fn,
1018 };
1019
1020 static clib_error_t *
1021 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1022                                 unformat_input_t * input,
1023                                 vlib_cli_command_t * cmd)
1024
1025 {
1026   vnet_main_t *vnm = vnet_get_main();
1027   u32 sw_if_index0=0, sw_if_index;
1028   vnet_sw_interface_t *swif;
1029   ip4_address_t *ia0;
1030
1031   while (unformat_check_input(input) != UNFORMAT_END_OF_INPUT)
1032     {
1033
1034       if (unformat(input, "%U",
1035                    unformat_vnet_sw_interface, vnm, &sw_if_index0))
1036         {
1037           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1038           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1039             swif->unnumbered_sw_if_index : sw_if_index0;
1040           ia0 = ip4_interface_first_address(&ip4_main, sw_if_index, 0);
1041           if (ia0)
1042             {
1043               vlib_cli_output (vm, "%=20s%=20s", "interface",
1044                                "source IP address");
1045
1046               vlib_cli_output (vm, "%=20U%=20U",
1047                                format_vnet_sw_if_index_name,
1048                                vnm, sw_if_index0,
1049                                format_ip4_address, ia0);
1050             }
1051           else
1052             vlib_cli_output (vm, "%=34s %=20U",
1053                              "No IPv4 address configured on",
1054                              format_vnet_sw_if_index_name,
1055                              vnm, sw_if_index);
1056         }
1057       else
1058         break;
1059     }
1060
1061   return 0;
1062 }
1063
1064 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1065   .path = "show dhcp option-82-address interface",
1066   .short_help = "show dhcp option-82-address interface <interface>",
1067   .function = dhcp_option_82_address_show_command_fn,
1068 };