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 {
  37 #define _(s,n) DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s,
  38   foreach_dhcp_proxy_to_server_input_next
  39 #undef _
  40     DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
  41 } dhcp_proxy_to_server_input_next_t;
  42
  43 typedef struct
  44 {
  45   /* 0 => to server, 1 => to client */
  46   int which;
  47   ip4_address_t trace_ip4_address;
  48   u32 error;
  49   u32 sw_if_index;
  50   u32 original_sw_if_index;
  51 } dhcp_proxy_trace_t;
  52
  53 #define VPP_DHCP_OPTION82_SUB1_SIZE   6
  54 #define VPP_DHCP_OPTION82_SUB5_SIZE   6
  55 #define VPP_DHCP_OPTION82_VSS_SIZE    12
  56 #define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
  57                                 VPP_DHCP_OPTION82_SUB5_SIZE + \
  58                                 VPP_DHCP_OPTION82_VSS_SIZE +3)
  59
  60 static vlib_node_registration_t dhcp_proxy_to_server_node;
  61 static vlib_node_registration_t dhcp_proxy_to_client_node;
  62
  63 static u8 *
  64 format_dhcp_proxy_trace (u8 * s, va_list * args)
  65 {
  66   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  67   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  68   dhcp_proxy_trace_t *t = va_arg (*args, dhcp_proxy_trace_t *);
  69
  70   if (t->which == 0)
  71     s = format (s, "DHCP proxy: sent to server %U\n",
  72                 format_ip4_address, &t->trace_ip4_address, t->error);
  73   else
  74     s = format (s, "DHCP proxy: broadcast to client from %U\n",
  75                 format_ip4_address, &t->trace_ip4_address);
  76
  77   if (t->error != (u32) ~ 0)
  78     s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
  79
  80   s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
  81               t->original_sw_if_index, t->sw_if_index);
  82
  83   return s;
  84 }
  85
  86 static u8 *
  87 format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
  88 {
  89   dhcp_header_t *h = va_arg (*args, dhcp_header_t *);
  90   u32 max_header_bytes = va_arg (*args, u32);
  91   u32 header_bytes;
  92
  93   header_bytes = sizeof (h[0]);
  94   if (max_header_bytes != 0 && header_bytes > max_header_bytes)
  95     return format (s, "dhcp header truncated");
  96
  97   s = format (s, "DHCP Proxy");
  98
  99   return s;
 100 }
 101
 102 static uword
 103 dhcp_proxy_to_server_input (vlib_main_t * vm,
 104                             vlib_node_runtime_t * node,
 105                             vlib_frame_t * from_frame)
 106 {
 107   u32 n_left_from, next_index, *from, *to_next;
 108   dhcp_proxy_main_t *dpm = &dhcp_proxy_main;
 109   from = vlib_frame_vector_args (from_frame);
 110   n_left_from = from_frame->n_vectors;
 111   u32 pkts_to_server = 0, pkts_to_client = 0, pkts_no_server = 0;
 112   u32 pkts_no_interface_address = 0;
 113   u32 pkts_too_big = 0;
 114   ip4_main_t *im = &ip4_main;
 115
 116   next_index = node->cached_next_index;
 117
 118   while (n_left_from > 0)
 119     {
 120       u32 n_left_to_next;
 121
 122       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 123
 124       while (n_left_from > 0 && n_left_to_next > 0)
 125         {
 126           u32 bi0;
 127           vlib_buffer_t *b0;
 128           udp_header_t *u0;
 129           dhcp_header_t *h0;
 130           ip4_header_t *ip0;
 131           u32 next0;
 132           u32 old0, new0;
 133           ip_csum_t sum0;
 134           u32 error0 = (u32) ~ 0;
 135           u32 sw_if_index = 0;
 136           u32 original_sw_if_index = 0;
 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, *end;
 142           u32 len = 0;
 143           u8 is_discover = 0;
 144           int space_left;
 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 ==
 163               clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_server))
 164             {
 165               vlib_buffer_advance (b0, sizeof (*u0));
 166               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
 167               error0 = 0;
 168               pkts_to_client++;
 169               goto do_enqueue;
 170             }
 171
 172           rx_sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 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           if (!vlib_buffer_chain_linearize (vm, b0))
 185             {
 186               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
 187               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 188               pkts_too_big++;
 189               goto do_trace;
 190             }
 191           space_left = vlib_buffer_space_left_at_end (vm, b0);
 192           /* cant parse chains...
 193            * and we need some space for option 82*/
 194           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 ||
 195               space_left < VPP_DHCP_OPTION82_SIZE)
 196             {
 197               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
 198               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 199               pkts_too_big++;
 200               goto do_trace;
 201             }
 202
 203           server = &proxy->dhcp_servers[0];
 204           vlib_buffer_advance (b0, -(sizeof (*ip0)));
 205           ip0 = vlib_buffer_get_current (b0);
 206
 207           /* disable UDP checksum */
 208           u0->checksum = 0;
 209           sum0 = ip0->checksum;
 210           old0 = ip0->dst_address.as_u32;
 211           new0 = server->dhcp_server.ip4.as_u32;
 212           ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 213           sum0 = ip_csum_update (sum0, old0, new0,
 214                                  ip4_header_t /* structure */ ,
 215                                  dst_address /* changed member */ );
 216           ip0->checksum = ip_csum_fold (sum0);
 217
 218           sum0 = ip0->checksum;
 219           old0 = ip0->src_address.as_u32;
 220           new0 = proxy->dhcp_src_address.ip4.as_u32;
 221           ip0->src_address.as_u32 = new0;
 222           sum0 = ip_csum_update (sum0, old0, new0,
 223                                  ip4_header_t /* structure */ ,
 224                                  src_address /* changed member */ );
 225           ip0->checksum = ip_csum_fold (sum0);
 226
 227           /* Send to DHCP server via the configured FIB */
 228           vnet_buffer (b0)->sw_if_index[VLIB_TX] = server->server_fib_index;
 229
 230           h0->gateway_ip_address = proxy->dhcp_src_address.ip4;
 231           pkts_to_server++;
 232
 233           o = h0->options;
 234           end = (void *) vlib_buffer_get_tail (b0);
 235
 236           /* TLVs are not performance-friendly... */
 237           while (o->option != DHCP_PACKET_OPTION_END && o < end)
 238             {
 239               if (DHCP_PACKET_OPTION_MSG_TYPE == o->option)
 240                 {
 241                   if (DHCP_PACKET_DISCOVER == o->data[0])
 242                     {
 243                       is_discover = 1;
 244                     }
 245                 }
 246               o = (dhcp_option_t *) (o->data + o->length);
 247             }
 248
 249           if (o->option == DHCP_PACKET_OPTION_END && o <= end)
 250             {
 251               vnet_main_t *vnm = vnet_get_main ();
 252               u16 old_l0, new_l0;
 253               ip4_address_t _ia0, *ia0 = &_ia0;
 254               dhcp_vss_t *vss;
 255               vnet_sw_interface_t *swif;
 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               /*
 264                * Get the first ip4 address on the [client-side]
 265                * RX interface, if not unnumbered. otherwise use
 266                * the loopback interface's ip address.
 267                */
 268               ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 269
 270               if (ia0 == 0)
 271                 {
 272                   error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 273                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 274                   pkts_no_interface_address++;
 275                   goto do_trace;
 276                 }
 277
 278               /* Add option 82 */
 279               o->option = 82;   /* option 82 */
 280               o->length = 12;   /* 12 octets to follow */
 281               o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
 282               o->data[1] = 4;   /* length of suboption */
 283               u32 *o_ifid = (u32 *) & o->data[2];
 284               *o_ifid = clib_host_to_net_u32 (original_sw_if_index);
 285               o->data[6] = 5;   /* suboption 5 (client RX intfc address) */
 286               o->data[7] = 4;   /* length 4 */
 287               u32 *o_addr = (u32 *) & o->data[8];
 288               *o_addr = ia0->as_u32;
 289               o->data[12] = DHCP_PACKET_OPTION_END;
 290
 291               vss = dhcp_get_vss_info (dpm, fib_index, FIB_PROTOCOL_IP4);
 292               if (vss)
 293                 {
 294                   u32 id_len;   /* length of VPN ID */
 295
 296                   if (vss->vss_type == VSS_TYPE_VPN_ID)
 297                     {
 298                       id_len = sizeof (vss->vpn_id);    /* vpn_id is 7 bytes */
 299                       memcpy (&o->data[15], vss->vpn_id, id_len);
 300                     }
 301                   else if (vss->vss_type == VSS_TYPE_ASCII)
 302                     {
 303                       id_len = vec_len (vss->vpn_ascii_id);
 304                       memcpy (&o->data[15], vss->vpn_ascii_id, id_len);
 305                     }
 306                   else          /* must be VSS_TYPE_DEFAULT, no VPN ID */
 307                     id_len = 0;
 308
 309                   o->data[12] = 151;    /* vss suboption */
 310                   o->data[13] = id_len + 1;     /* length: vss_type + id_len */
 311                   o->data[14] = vss->vss_type;  /* vss option type */
 312                   o->data[15 + id_len] = 152;   /* vss control suboption */
 313                   o->data[16 + id_len] = 0;     /* length */
 314                   o->data[17 + id_len] = DHCP_PACKET_OPTION_END;        /* "end-of-options" (0xFF) */
 315                   /* 5 bytes for suboption headers 151+len, 152+len and 0xFF */
 316                   o->length += id_len + 5;
 317                 }
 318
 319               len = o->length + 3;
 320               b0->current_length += len;
 321               /* Fix IP header length and checksum */
 322               old_l0 = ip0->length;
 323               new_l0 = clib_net_to_host_u16 (old_l0);
 324               new_l0 += len;
 325               new_l0 = clib_host_to_net_u16 (new_l0);
 326               ip0->length = new_l0;
 327               sum0 = ip0->checksum;
 328               sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 329                                      length /* changed member */ );
 330               ip0->checksum = ip_csum_fold (sum0);
 331
 332               /* Fix UDP length */
 333               new_l0 = clib_net_to_host_u16 (u0->length);
 334               new_l0 += len;
 335               u0->length = clib_host_to_net_u16 (new_l0);
 336             }
 337           else
 338             {
 339               vlib_node_increment_counter
 340                 (vm, dhcp_proxy_to_server_node.index,
 341                  DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
 342             }
 343
 344           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
 345
 346           /*
 347            * If we have multiple servers configured and this is the
 348            * client's discover message, then send copies to each of
 349            * those servers
 350            */
 351           if (is_discover && vec_len (proxy->dhcp_servers) > 1)
 352             {
 353               u32 ii;
 354
 355               for (ii = 1; ii < vec_len (proxy->dhcp_servers); ii++)
 356                 {
 357                   vlib_buffer_t *c0;
 358                   u32 ci0;
 359
 360                   c0 = vlib_buffer_copy (vm, b0);
 361                   VLIB_BUFFER_TRACE_TRAJECTORY_INIT (c0);
 362                   ci0 = vlib_get_buffer_index (vm, c0);
 363                   server = &proxy->dhcp_servers[ii];
 364
 365                   ip0 = vlib_buffer_get_current (c0);
 366
 367                   sum0 = ip0->checksum;
 368                   old0 = ip0->dst_address.as_u32;
 369                   new0 = server->dhcp_server.ip4.as_u32;
 370                   ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 371                   sum0 = ip_csum_update (sum0, old0, new0,
 372                                          ip4_header_t /* structure */ ,
 373                                          dst_address /* changed member */ );
 374                   ip0->checksum = ip_csum_fold (sum0);
 375
 376                   to_next[0] = ci0;
 377                   to_next += 1;
 378                   n_left_to_next -= 1;
 379
 380                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 381                                                    to_next, n_left_to_next,
 382                                                    ci0, next0);
 383
 384                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 385                     {
 386                       dhcp_proxy_trace_t *tr;
 387
 388                       tr = vlib_add_trace (vm, node, c0, sizeof (*tr));
 389                       tr->which = 0;    /* to server */
 390                       tr->error = error0;
 391                       tr->original_sw_if_index = original_sw_if_index;
 392                       tr->sw_if_index = sw_if_index;
 393                       if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 394                         tr->trace_ip4_address.as_u32 =
 395                           server->dhcp_server.ip4.as_u32;
 396                     }
 397
 398                   if (PREDICT_FALSE (0 == n_left_to_next))
 399                     {
 400                       vlib_put_next_frame (vm, node, next_index,
 401                                            n_left_to_next);
 402                       vlib_get_next_frame (vm, node, next_index,
 403                                            to_next, n_left_to_next);
 404                     }
 405                 }
 406             }
 407         do_trace:
 408           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 409             {
 410               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 411                                                        b0, sizeof (*tr));
 412               tr->which = 0;    /* to server */
 413               tr->error = error0;
 414               tr->original_sw_if_index = original_sw_if_index;
 415               tr->sw_if_index = sw_if_index;
 416               if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 417                 tr->trace_ip4_address.as_u32 =
 418                   proxy->dhcp_servers[0].dhcp_server.ip4.as_u32;
 419             }
 420
 421         do_enqueue:
 422           to_next[0] = bi0;
 423           to_next += 1;
 424           n_left_to_next -= 1;
 425
 426           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 427                                            to_next, n_left_to_next,
 428                                            bi0, next0);
 429         }
 430
 431       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 432     }
 433   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 434                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
 435                                pkts_to_client);
 436   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 437                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
 438                                pkts_to_server);
 439   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 440                                DHCP_PROXY_ERROR_NO_SERVER, pkts_no_server);
 441   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 442                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
 443                                pkts_no_interface_address);
 444   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 445                                DHCP_PROXY_ERROR_PKT_TOO_BIG, pkts_too_big);
 446   return from_frame->n_vectors;
 447 }
 448
 449 /* *INDENT-OFF* */
 450 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node, static) = {
 451   .function = dhcp_proxy_to_server_input,
 452   .name = "dhcp-proxy-to-server",
 453   /* Takes a vector of packets. */
 454   .vector_size = sizeof (u32),
 455
 456   .n_errors = DHCP_PROXY_N_ERROR,
 457   .error_strings = dhcp_proxy_error_strings,
 458
 459   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
 460   .next_nodes = {
 461 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
 462     foreach_dhcp_proxy_to_server_input_next
 463 #undef _
 464   },
 465
 466   .format_buffer = format_dhcp_proxy_header_with_length,
 467   .format_trace = format_dhcp_proxy_trace,
 468 #if 0
 469   .unformat_buffer = unformat_dhcp_proxy_header,
 470 #endif
 471 };
 472 /* *INDENT-ON* */
 473
 474 static uword
 475 dhcp_proxy_to_client_input (vlib_main_t * vm,
 476                             vlib_node_runtime_t * node,
 477                             vlib_frame_t * from_frame)
 478 {
 479   u32 n_left_from, *from;
 480   ethernet_main_t *em = vnet_get_ethernet_main ();
 481   dhcp_proxy_main_t *dpm = &dhcp_proxy_main;
 482   vnet_main_t *vnm = vnet_get_main ();
 483   ip4_main_t *im = &ip4_main;
 484
 485   from = vlib_frame_vector_args (from_frame);
 486   n_left_from = from_frame->n_vectors;
 487
 488   while (n_left_from > 0)
 489     {
 490       u32 bi0;
 491       vlib_buffer_t *b0;
 492       udp_header_t *u0;
 493       dhcp_header_t *h0;
 494       ip4_header_t *ip0 = 0;
 495       ip4_address_t *ia0 = 0;
 496       u32 old0, new0;
 497       ip_csum_t sum0;
 498       ethernet_interface_t *ei0;
 499       ethernet_header_t *mac0;
 500       vnet_hw_interface_t *hi0;
 501       vlib_frame_t *f0;
 502       u32 *to_next0;
 503       u32 sw_if_index = ~0;
 504       vnet_sw_interface_t *si0;
 505       u32 error0 = (u32) ~ 0;
 506       vnet_sw_interface_t *swif;
 507       u32 fib_index;
 508       dhcp_proxy_t *proxy;
 509       dhcp_server_t *server;
 510       u32 original_sw_if_index = (u32) ~ 0;
 511       ip4_address_t relay_addr = {
 512         .as_u32 = 0,
 513       };
 514
 515       bi0 = from[0];
 516       from += 1;
 517       n_left_from -= 1;
 518
 519       b0 = vlib_get_buffer (vm, bi0);
 520       h0 = vlib_buffer_get_current (b0);
 521
 522       /*
 523        * udp_local hands us the DHCP header, need udp hdr,
 524        * ip hdr to relay to client
 525        */
 526       vlib_buffer_advance (b0, -(sizeof (*u0)));
 527       u0 = vlib_buffer_get_current (b0);
 528
 529       vlib_buffer_advance (b0, -(sizeof (*ip0)));
 530       ip0 = vlib_buffer_get_current (b0);
 531
 532       /* Consumed by dhcp client code? */
 533       if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
 534         continue;
 535
 536       if (1 /* dpm->insert_option_82 */ )
 537         {
 538           /* linearize needed to "unclone" and scan options */
 539           int rv = vlib_buffer_chain_linearize (vm, b0);
 540           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 || !rv)
 541             {
 542               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
 543               goto drop_packet;
 544             }
 545
 546           dhcp_option_t *o = h0->options, *end =
 547             (void *) vlib_buffer_get_tail (b0);
 548
 549           /* Parse through TLVs looking for option 82.
 550              The circuit-ID is the FIB number we need
 551              to track down the client-facing interface */
 552
 553           while (o->option != DHCP_PACKET_OPTION_END && o < end)
 554             {
 555               if (o->option == 82)
 556                 {
 557                   u32 vss_exist = 0;
 558                   u32 vss_ctrl = 0;
 559                   dhcp_option_t *sub = (dhcp_option_t *) & o->data[0];
 560                   dhcp_option_t *subend =
 561                     (dhcp_option_t *) (o->data + o->length);
 562                   while (sub->option != DHCP_PACKET_OPTION_END
 563                          && sub < subend)
 564                     {
 565                       /* If this is one of ours, it will have
 566                          total length 12, circuit-id suboption type,
 567                          and the sw_if_index */
 568                       if (sub->option == 1 && sub->length == 4)
 569                         {
 570                           sw_if_index = ((sub->data[0] << 24) |
 571                                          (sub->data[1] << 16) |
 572                                          (sub->data[2] << 8) |
 573                                          (sub->data[3]));
 574                         }
 575                       else if (sub->option == 5 && sub->length == 4)
 576                         {
 577                           relay_addr.as_u8[0] = sub->data[0];
 578                           relay_addr.as_u8[1] = sub->data[1];
 579                           relay_addr.as_u8[2] = sub->data[2];
 580                           relay_addr.as_u8[3] = sub->data[3];
 581                         }
 582                       else if (sub->option == 151 &&
 583                                sub->length == 7 && sub->data[0] == 1)
 584                         vss_exist = 1;
 585                       else if (sub->option == 152 && sub->length == 0)
 586                         vss_ctrl = 1;
 587                       sub = (dhcp_option_t *) (sub->data + sub->length);
 588                     }
 589                   if (vss_ctrl && vss_exist)
 590                     vlib_node_increment_counter
 591                       (vm, dhcp_proxy_to_client_node.index,
 592                        DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 593
 594                 }
 595               o = (dhcp_option_t *) (o->data + o->length);
 596             }
 597         }
 598
 599       if (sw_if_index == (u32) ~ 0)
 600         {
 601           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 602
 603         drop_packet:
 604           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 605                                        error0, 1);
 606           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 607           to_next0 = vlib_frame_vector_args (f0);
 608           to_next0[0] = bi0;
 609           f0->n_vectors = 1;
 610           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 611           goto do_trace;
 612         }
 613
 614       if (relay_addr.as_u32 == 0)
 615         {
 616           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ADDR;
 617           goto drop_packet;
 618         }
 619
 620       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 621         {
 622           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ITF;
 623           goto drop_packet;
 624         }
 625
 626       fib_index = im->fib_index_by_sw_if_index[sw_if_index];
 627       proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
 628
 629       if (PREDICT_FALSE (NULL == proxy))
 630         {
 631           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 632           goto drop_packet;
 633         }
 634
 635       vec_foreach (server, proxy->dhcp_servers)
 636       {
 637         if (ip0->src_address.as_u32 == server->dhcp_server.ip4.as_u32)
 638           {
 639             goto server_found;
 640           }
 641       }
 642
 643       error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 644       goto drop_packet;
 645
 646     server_found:
 647       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 648
 649       swif = vnet_get_sw_interface (vnm, sw_if_index);
 650       original_sw_if_index = sw_if_index;
 651       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 652         sw_if_index = swif->unnumbered_sw_if_index;
 653
 654       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 655       if (ia0 == 0)
 656         {
 657           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 658           goto drop_packet;
 659         }
 660
 661       if (relay_addr.as_u32 != ia0->as_u32)
 662         {
 663           error0 = DHCP_PROXY_ERROR_BAD_YIADDR;
 664           goto drop_packet;
 665         }
 666
 667       u0->checksum = 0;
 668       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 669       sum0 = ip0->checksum;
 670       old0 = ip0->dst_address.as_u32;
 671       new0 = 0xFFFFFFFF;
 672       ip0->dst_address.as_u32 = new0;
 673       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 674                              dst_address /* offset of changed member */ );
 675       ip0->checksum = ip_csum_fold (sum0);
 676
 677       sum0 = ip0->checksum;
 678       old0 = ip0->src_address.as_u32;
 679       new0 = ia0->as_u32;
 680       ip0->src_address.as_u32 = new0;
 681       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 682                              src_address /* offset of changed member */ );
 683       ip0->checksum = ip_csum_fold (sum0);
 684
 685       vlib_buffer_advance (b0, -(sizeof (ethernet_header_t)));
 686       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 687       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 688         vlib_buffer_advance (b0, -4 /* space for VLAN tag */ );
 689
 690       mac0 = vlib_buffer_get_current (b0);
 691
 692       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 693       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 694       clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 695       clib_memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 696       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 697         clib_net_to_host_u16 (0x8100) : clib_net_to_host_u16 (0x0800);
 698
 699       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 700         {
 701           u32 *vlan_tag = (u32 *) (mac0 + 1);
 702           u32 tmp;
 703           tmp = (si0->sub.id << 16) | 0x0800;
 704           *vlan_tag = clib_host_to_net_u32 (tmp);
 705         }
 706
 707       /* $$$ This needs to be rewritten, for sure */
 708       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 709       to_next0 = vlib_frame_vector_args (f0);
 710       to_next0[0] = bi0;
 711       f0->n_vectors = 1;
 712       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 713
 714     do_trace:
 715       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 716         {
 717           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 718                                                    b0, sizeof (*tr));
 719           tr->which = 1;        /* to client */
 720           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 721           tr->error = error0;
 722           tr->original_sw_if_index = original_sw_if_index;
 723           tr->sw_if_index = sw_if_index;
 724         }
 725     }
 726
 727   return from_frame->n_vectors;
 728 }
 729
 730 /* *INDENT-OFF* */
 731 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node, static) = {
 732   .function = dhcp_proxy_to_client_input,
 733   .name = "dhcp-proxy-to-client",
 734   /* Takes a vector of packets. */
 735   .vector_size = sizeof (u32),
 736
 737   .n_errors = DHCP_PROXY_N_ERROR,
 738   .error_strings = dhcp_proxy_error_strings,
 739   .format_buffer = format_dhcp_proxy_header_with_length,
 740   .format_trace = format_dhcp_proxy_trace,
 741 #if 0
 742   .unformat_buffer = unformat_dhcp_proxy_header,
 743 #endif
 744 };
 745 /* *INDENT-ON* */
 746
 747 void
 748 dhcp_maybe_register_udp_ports (dhcp_port_reg_flags_t ports)
 749 {
 750   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 751   vlib_main_t *vm = dm->vlib_main;
 752   int port_regs_diff = dm->udp_ports_registered ^ ports;
 753
 754   if (!port_regs_diff)
 755     return;
 756
 757   if ((port_regs_diff & DHCP_PORT_REG_CLIENT) & ports)
 758     udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
 759                            dhcp_proxy_to_client_node.index, 1 /* is_ip4 */ );
 760
 761   if ((port_regs_diff & DHCP_PORT_REG_SERVER) & ports)
 762     udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
 763                            dhcp_proxy_to_server_node.index, 1 /* is_ip4 */ );
 764
 765   dm->udp_ports_registered |= ports;
 766 }
 767
 768 static clib_error_t *
 769 dhcp4_proxy_init (vlib_main_t * vm)
 770 {
 771   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 772   vlib_node_t *error_drop_node;
 773
 774   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 775   dm->error_drop_node_index = error_drop_node->index;
 776   dm->vlib_main = vm;
 777
 778   return 0;
 779 }
 780
 781
 782 VLIB_INIT_FUNCTION (dhcp4_proxy_init);
 783
 784 int
 785 dhcp4_proxy_set_server (ip46_address_t * addr,
 786                         ip46_address_t * src_addr,
 787                         u32 rx_table_id, u32 server_table_id, int is_del)
 788 {
 789   u32 rx_fib_index = 0;
 790   int rc = 0;
 791
 792   const fib_prefix_t all_1s = {
 793     .fp_len = 32,
 794     .fp_addr.ip4.as_u32 = 0xffffffff,
 795     .fp_proto = FIB_PROTOCOL_IP4,
 796   };
 797
 798   if (ip46_address_is_zero (addr))
 799     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 800
 801   if (ip46_address_is_zero (src_addr))
 802     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 803
 804   dhcp_maybe_register_udp_ports (DHCP_PORT_REG_CLIENT | DHCP_PORT_REG_SERVER);
 805
 806   rx_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 807                                                     rx_table_id,
 808                                                     FIB_SOURCE_DHCP);
 809
 810   if (is_del)
 811     {
 812       if (dhcp_proxy_server_del (FIB_PROTOCOL_IP4, rx_fib_index,
 813                                  addr, server_table_id))
 814         {
 815           fib_table_entry_special_remove (rx_fib_index,
 816                                           &all_1s, FIB_SOURCE_DHCP);
 817           fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 818         }
 819     }
 820   else
 821     {
 822       if (dhcp_proxy_server_add (FIB_PROTOCOL_IP4,
 823                                  addr, src_addr,
 824                                  rx_fib_index, server_table_id))
 825         {
 826           fib_table_entry_special_add (rx_fib_index,
 827                                        &all_1s,
 828                                        FIB_SOURCE_DHCP, FIB_ENTRY_FLAG_LOCAL);
 829           fib_table_lock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 830         }
 831     }
 832   fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 833
 834   return (rc);
 835 }
 836
 837 static clib_error_t *
 838 dhcp4_proxy_set_command_fn (vlib_main_t * vm,
 839                             unformat_input_t * input,
 840                             vlib_cli_command_t * cmd)
 841 {
 842   ip46_address_t server_addr, src_addr;
 843   u32 server_table_id = 0, rx_table_id = 0;
 844   int is_del = 0;
 845   int set_src = 0, set_server = 0;
 846
 847   clib_memset (&server_addr, 0, sizeof (server_addr));
 848   clib_memset (&src_addr, 0, sizeof (src_addr));
 849
 850   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 851     {
 852       if (unformat (input, "server %U",
 853                     unformat_ip4_address, &server_addr.ip4))
 854         set_server = 1;
 855       else if (unformat (input, "server-fib-id %d", &server_table_id))
 856         ;
 857       else if (unformat (input, "rx-fib-id %d", &rx_table_id))
 858         ;
 859       else if (unformat (input, "src-address %U",
 860                          unformat_ip4_address, &src_addr.ip4))
 861         set_src = 1;
 862       else if (unformat (input, "delete") || unformat (input, "del"))
 863         is_del = 1;
 864       else
 865         break;
 866     }
 867
 868   if (is_del || (set_server && set_src))
 869     {
 870       int rv;
 871
 872       rv = dhcp4_proxy_set_server (&server_addr, &src_addr, rx_table_id,
 873                                    server_table_id, is_del);
 874       switch (rv)
 875         {
 876         case 0:
 877           return 0;
 878
 879         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 880           return clib_error_return (0, "Invalid server address");
 881
 882         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 883           return clib_error_return (0, "Invalid src address");
 884
 885         case VNET_API_ERROR_NO_SUCH_ENTRY:
 886           return clib_error_return
 887             (0, "Fib id %d: no per-fib DHCP server configured", rx_table_id);
 888
 889         default:
 890           return clib_error_return (0, "BUG: rv %d", rv);
 891         }
 892     }
 893   else
 894     return clib_error_return (0, "parse error`%U'",
 895                               format_unformat_error, input);
 896 }
 897
 898 /* *INDENT-OFF* */
 899 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 900   .path = "set dhcp proxy",
 901   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [server-fib-id <n>] [rx-fib-id <n>]",
 902   .function = dhcp4_proxy_set_command_fn,
 903 };
 904 /* *INDENT-ON* */
 905
 906 static u8 *
 907 format_dhcp4_proxy_server (u8 * s, va_list * args)
 908 {
 909   dhcp_proxy_t *proxy = va_arg (*args, dhcp_proxy_t *);
 910   ip4_fib_t *rx_fib, *server_fib;
 911   dhcp_server_t *server;
 912
 913   if (proxy == 0)
 914     {
 915       s = format (s, "%=14s%=16s%s", "RX FIB", "Src Address",
 916                   "Servers FIB,Address");
 917       return s;
 918     }
 919
 920   rx_fib = ip4_fib_get (proxy->rx_fib_index);
 921
 922   s = format (s, "%=14u%=16U",
 923               rx_fib->table_id,
 924               format_ip46_address, &proxy->dhcp_src_address, IP46_TYPE_ANY);
 925
 926   vec_foreach (server, proxy->dhcp_servers)
 927   {
 928     server_fib = ip4_fib_get (server->server_fib_index);
 929     s = format (s, "%u,%U  ",
 930                 server_fib->table_id,
 931                 format_ip46_address, &server->dhcp_server, IP46_TYPE_ANY);
 932   }
 933   return s;
 934 }
 935
 936 static int
 937 dhcp4_proxy_show_walk (dhcp_proxy_t * server, void *ctx)
 938 {
 939   vlib_main_t *vm = ctx;
 940
 941   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, server);
 942
 943   return (1);
 944 }
 945
 946 static clib_error_t *
 947 dhcp4_proxy_show_command_fn (vlib_main_t * vm,
 948                              unformat_input_t * input,
 949                              vlib_cli_command_t * cmd)
 950 {
 951   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server,
 952                    NULL /* header line */ );
 953
 954   dhcp_proxy_walk (FIB_PROTOCOL_IP4, dhcp4_proxy_show_walk, vm);
 955
 956   return (NULL);
 957 }
 958
 959 /* *INDENT-OFF* */
 960 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 961   .path = "show dhcp proxy",
 962   .short_help = "Display dhcp proxy server info",
 963   .function = dhcp4_proxy_show_command_fn,
 964 };
 965 /* *INDENT-ON* */
 966
 967 static clib_error_t *
 968 dhcp_option_82_vss_fn (vlib_main_t * vm,
 969                        unformat_input_t * input, vlib_cli_command_t * cmd)
 970 {
 971   u8 is_del = 0, vss_type = VSS_TYPE_DEFAULT;
 972   u32 oui = 0, fib_id = 0, tbl_id = ~0;
 973   u8 *vpn_ascii_id = 0;
 974
 975   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 976     {
 977       if (unformat (input, "table %d", &tbl_id))
 978         ;
 979       else if (unformat (input, "oui %d", &oui))
 980         vss_type = VSS_TYPE_VPN_ID;
 981       else if (unformat (input, "vpn-id %d", &fib_id))
 982         vss_type = VSS_TYPE_VPN_ID;
 983       else if (unformat (input, "vpn-ascii-id %s", &vpn_ascii_id))
 984         vss_type = VSS_TYPE_ASCII;
 985       else if (unformat (input, "delete") || unformat (input, "del"))
 986         is_del = 1;
 987       else
 988         break;
 989     }
 990
 991   if (tbl_id == ~0)
 992     return clib_error_return (0, "no table ID specified.");
 993
 994   int rv = dhcp_proxy_set_vss (FIB_PROTOCOL_IP4, tbl_id, vss_type,
 995                                vpn_ascii_id, oui, fib_id, is_del);
 996   switch (rv)
 997     {
 998     case 0:
 999       return 0;
1000     case VNET_API_ERROR_NO_SUCH_ENTRY:
1001       return clib_error_return (0,
1002                                 "option 82 vss for table %d not found in in pool.",
1003                                 tbl_id);
1004     default:
1005       return clib_error_return (0, "BUG: rv %d", rv);
1006
1007     }
1008 }
1009
1010 /* *INDENT-OFF* */
1011 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
1012   .path = "set dhcp option-82 vss",
1013   .short_help = "set dhcp option-82 vss [del] table <table id> [oui <n> vpn-id <n> | vpn-ascii-id <text>]",
1014   .function = dhcp_option_82_vss_fn,
1015 };
1016 /* *INDENT-ON* */
1017
1018 static clib_error_t *
1019 dhcp_vss_show_command_fn (vlib_main_t * vm,
1020                           unformat_input_t * input, vlib_cli_command_t * cmd)
1021 {
1022   dhcp_vss_walk (FIB_PROTOCOL_IP4, dhcp_vss_show_walk, vm);
1023
1024   return (NULL);
1025 }
1026
1027 /* *INDENT-OFF* */
1028 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1029   .path = "show dhcp vss",
1030   .short_help = "show dhcp VSS",
1031   .function = dhcp_vss_show_command_fn,
1032 };
1033 /* *INDENT-ON* */
1034
1035 static clib_error_t *
1036 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1037                                         unformat_input_t * input,
1038                                         vlib_cli_command_t * cmd)
1039 {
1040   vnet_main_t *vnm = vnet_get_main ();
1041   u32 sw_if_index0 = 0, sw_if_index;
1042   vnet_sw_interface_t *swif;
1043   ip4_address_t *ia0;
1044
1045   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
1046     {
1047
1048       if (unformat (input, "%U",
1049                     unformat_vnet_sw_interface, vnm, &sw_if_index0))
1050         {
1051           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1052           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1053             swif->unnumbered_sw_if_index : sw_if_index0;
1054           ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
1055           if (ia0)
1056             {
1057               vlib_cli_output (vm, "%=20s%=20s", "interface",
1058                                "source IP address");
1059
1060               vlib_cli_output (vm, "%=20U%=20U",
1061                                format_vnet_sw_if_index_name,
1062                                vnm, sw_if_index0, format_ip4_address, ia0);
1063             }
1064           else
1065             vlib_cli_output (vm, "%=34s %=20U",
1066                              "No IPv4 address configured on",
1067                              format_vnet_sw_if_index_name, vnm, sw_if_index);
1068         }
1069       else
1070         break;
1071     }
1072
1073   return 0;
1074 }
1075
1076 /* *INDENT-OFF* */
1077 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1078   .path = "show dhcp option-82-address interface",
1079   .short_help = "show dhcp option-82-address interface <interface>",
1080   .function = dhcp_option_82_address_show_command_fn,
1081 };
1082 /* *INDENT-ON* */
1083
1084 /*
1085  * fd.io coding-style-patch-verification: ON
1086  *
1087  * Local Variables:
1088  * eval: (c-set-style "gnu")
1089  * End:
1090  */