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           space_left = vlib_buffer_chain_linearize (vm, b0);
 185           /* cant parse chains...
 186            * and we need some space for option 82*/
 187           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 ||
 188               space_left < VPP_DHCP_OPTION82_SIZE)
 189             {
 190               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
 191               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 192               pkts_too_big++;
 193               goto do_trace;
 194             }
 195
 196           server = &proxy->dhcp_servers[0];
 197           vlib_buffer_advance (b0, -(sizeof (*ip0)));
 198           ip0 = vlib_buffer_get_current (b0);
 199
 200           /* disable UDP checksum */
 201           u0->checksum = 0;
 202           sum0 = ip0->checksum;
 203           old0 = ip0->dst_address.as_u32;
 204           new0 = server->dhcp_server.ip4.as_u32;
 205           ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 206           sum0 = ip_csum_update (sum0, old0, new0,
 207                                  ip4_header_t /* structure */ ,
 208                                  dst_address /* changed member */ );
 209           ip0->checksum = ip_csum_fold (sum0);
 210
 211           sum0 = ip0->checksum;
 212           old0 = ip0->src_address.as_u32;
 213           new0 = proxy->dhcp_src_address.ip4.as_u32;
 214           ip0->src_address.as_u32 = new0;
 215           sum0 = ip_csum_update (sum0, old0, new0,
 216                                  ip4_header_t /* structure */ ,
 217                                  src_address /* changed member */ );
 218           ip0->checksum = ip_csum_fold (sum0);
 219
 220           /* Send to DHCP server via the configured FIB */
 221           vnet_buffer (b0)->sw_if_index[VLIB_TX] = server->server_fib_index;
 222
 223           h0->gateway_ip_address = proxy->dhcp_src_address.ip4;
 224           pkts_to_server++;
 225
 226           o = h0->options;
 227           end = (void *) vlib_buffer_get_tail (b0);
 228
 229           /* TLVs are not performance-friendly... */
 230           while (o->option != DHCP_PACKET_OPTION_END && o < end)
 231             {
 232               if (DHCP_PACKET_OPTION_MSG_TYPE == o->option)
 233                 {
 234                   if (DHCP_PACKET_DISCOVER == o->data[0])
 235                     {
 236                       is_discover = 1;
 237                     }
 238                 }
 239               o = (dhcp_option_t *) (o->data + o->length);
 240             }
 241
 242           if (o->option == DHCP_PACKET_OPTION_END && o <= end)
 243             {
 244               vnet_main_t *vnm = vnet_get_main ();
 245               u16 old_l0, new_l0;
 246               ip4_address_t _ia0, *ia0 = &_ia0;
 247               dhcp_vss_t *vss;
 248               vnet_sw_interface_t *swif;
 249
 250               original_sw_if_index = sw_if_index =
 251                 vnet_buffer (b0)->sw_if_index[VLIB_RX];
 252               swif = vnet_get_sw_interface (vnm, sw_if_index);
 253               if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 254                 sw_if_index = swif->unnumbered_sw_if_index;
 255
 256               /*
 257                * Get the first ip4 address on the [client-side]
 258                * RX interface, if not unnumbered. otherwise use
 259                * the loopback interface's ip address.
 260                */
 261               ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 262
 263               if (ia0 == 0)
 264                 {
 265                   error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 266                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 267                   pkts_no_interface_address++;
 268                   goto do_trace;
 269                 }
 270
 271               /* Add option 82 */
 272               o->option = 82;   /* option 82 */
 273               o->length = 12;   /* 12 octets to follow */
 274               o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
 275               o->data[1] = 4;   /* length of suboption */
 276               u32 *o_ifid = (u32 *) & o->data[2];
 277               *o_ifid = clib_host_to_net_u32 (original_sw_if_index);
 278               o->data[6] = 5;   /* suboption 5 (client RX intfc address) */
 279               o->data[7] = 4;   /* length 4 */
 280               u32 *o_addr = (u32 *) & o->data[8];
 281               *o_addr = ia0->as_u32;
 282               o->data[12] = DHCP_PACKET_OPTION_END;
 283
 284               vss = dhcp_get_vss_info (dpm, fib_index, FIB_PROTOCOL_IP4);
 285               if (vss)
 286                 {
 287                   u32 id_len;   /* length of VPN ID */
 288
 289                   if (vss->vss_type == VSS_TYPE_VPN_ID)
 290                     {
 291                       id_len = sizeof (vss->vpn_id);    /* vpn_id is 7 bytes */
 292                       memcpy (&o->data[15], vss->vpn_id, id_len);
 293                     }
 294                   else if (vss->vss_type == VSS_TYPE_ASCII)
 295                     {
 296                       id_len = vec_len (vss->vpn_ascii_id);
 297                       memcpy (&o->data[15], vss->vpn_ascii_id, id_len);
 298                     }
 299                   else          /* must be VSS_TYPE_DEFAULT, no VPN ID */
 300                     id_len = 0;
 301
 302                   o->data[12] = 151;    /* vss suboption */
 303                   o->data[13] = id_len + 1;     /* length: vss_type + id_len */
 304                   o->data[14] = vss->vss_type;  /* vss option type */
 305                   o->data[15 + id_len] = 152;   /* vss control suboption */
 306                   o->data[16 + id_len] = 0;     /* length */
 307                   o->data[17 + id_len] = DHCP_PACKET_OPTION_END;        /* "end-of-options" (0xFF) */
 308                   /* 5 bytes for suboption headers 151+len, 152+len and 0xFF */
 309                   o->length += id_len + 5;
 310                 }
 311
 312               len = o->length + 3;
 313               b0->current_length += len;
 314               /* Fix IP header length and checksum */
 315               old_l0 = ip0->length;
 316               new_l0 = clib_net_to_host_u16 (old_l0);
 317               new_l0 += len;
 318               new_l0 = clib_host_to_net_u16 (new_l0);
 319               ip0->length = new_l0;
 320               sum0 = ip0->checksum;
 321               sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
 322                                      length /* changed member */ );
 323               ip0->checksum = ip_csum_fold (sum0);
 324
 325               /* Fix UDP length */
 326               new_l0 = clib_net_to_host_u16 (u0->length);
 327               new_l0 += len;
 328               u0->length = clib_host_to_net_u16 (new_l0);
 329             }
 330           else
 331             {
 332               vlib_node_increment_counter
 333                 (vm, dhcp_proxy_to_server_node.index,
 334                  DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
 335             }
 336
 337           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
 338
 339           /*
 340            * If we have multiple servers configured and this is the
 341            * client's discover message, then send copies to each of
 342            * those servers
 343            */
 344           if (is_discover && vec_len (proxy->dhcp_servers) > 1)
 345             {
 346               u32 ii;
 347
 348               for (ii = 1; ii < vec_len (proxy->dhcp_servers); ii++)
 349                 {
 350                   vlib_buffer_t *c0;
 351                   u32 ci0;
 352
 353                   c0 = vlib_buffer_copy (vm, b0);
 354                   ci0 = vlib_get_buffer_index (vm, c0);
 355                   server = &proxy->dhcp_servers[ii];
 356
 357                   ip0 = vlib_buffer_get_current (c0);
 358
 359                   sum0 = ip0->checksum;
 360                   old0 = ip0->dst_address.as_u32;
 361                   new0 = server->dhcp_server.ip4.as_u32;
 362                   ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 363                   sum0 = ip_csum_update (sum0, old0, new0,
 364                                          ip4_header_t /* structure */ ,
 365                                          dst_address /* changed member */ );
 366                   ip0->checksum = ip_csum_fold (sum0);
 367
 368                   to_next[0] = ci0;
 369                   to_next += 1;
 370                   n_left_to_next -= 1;
 371
 372                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 373                                                    to_next, n_left_to_next,
 374                                                    ci0, next0);
 375
 376                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 377                     {
 378                       dhcp_proxy_trace_t *tr;
 379
 380                       tr = vlib_add_trace (vm, node, c0, sizeof (*tr));
 381                       tr->which = 0;    /* to server */
 382                       tr->error = error0;
 383                       tr->original_sw_if_index = original_sw_if_index;
 384                       tr->sw_if_index = sw_if_index;
 385                       if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 386                         tr->trace_ip4_address.as_u32 =
 387                           server->dhcp_server.ip4.as_u32;
 388                     }
 389
 390                   if (PREDICT_FALSE (0 == n_left_to_next))
 391                     {
 392                       vlib_put_next_frame (vm, node, next_index,
 393                                            n_left_to_next);
 394                       vlib_get_next_frame (vm, node, next_index,
 395                                            to_next, n_left_to_next);
 396                     }
 397                 }
 398             }
 399         do_trace:
 400           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 401             {
 402               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 403                                                        b0, sizeof (*tr));
 404               tr->which = 0;    /* to server */
 405               tr->error = error0;
 406               tr->original_sw_if_index = original_sw_if_index;
 407               tr->sw_if_index = sw_if_index;
 408               if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 409                 tr->trace_ip4_address.as_u32 =
 410                   proxy->dhcp_servers[0].dhcp_server.ip4.as_u32;
 411             }
 412
 413         do_enqueue:
 414           to_next[0] = bi0;
 415           to_next += 1;
 416           n_left_to_next -= 1;
 417
 418           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 419                                            to_next, n_left_to_next,
 420                                            bi0, next0);
 421         }
 422
 423       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 424     }
 425   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 426                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
 427                                pkts_to_client);
 428   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 429                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
 430                                pkts_to_server);
 431   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 432                                DHCP_PROXY_ERROR_NO_SERVER, pkts_no_server);
 433   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 434                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
 435                                pkts_no_interface_address);
 436   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
 437                                DHCP_PROXY_ERROR_PKT_TOO_BIG, pkts_too_big);
 438   return from_frame->n_vectors;
 439 }
 440
 441 /* *INDENT-OFF* */
 442 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node, static) = {
 443   .function = dhcp_proxy_to_server_input,
 444   .name = "dhcp-proxy-to-server",
 445   /* Takes a vector of packets. */
 446   .vector_size = sizeof (u32),
 447
 448   .n_errors = DHCP_PROXY_N_ERROR,
 449   .error_strings = dhcp_proxy_error_strings,
 450
 451   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
 452   .next_nodes = {
 453 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
 454     foreach_dhcp_proxy_to_server_input_next
 455 #undef _
 456   },
 457
 458   .format_buffer = format_dhcp_proxy_header_with_length,
 459   .format_trace = format_dhcp_proxy_trace,
 460 #if 0
 461   .unformat_buffer = unformat_dhcp_proxy_header,
 462 #endif
 463 };
 464 /* *INDENT-ON* */
 465
 466 static uword
 467 dhcp_proxy_to_client_input (vlib_main_t * vm,
 468                             vlib_node_runtime_t * node,
 469                             vlib_frame_t * from_frame)
 470 {
 471   u32 n_left_from, *from;
 472   ethernet_main_t *em = vnet_get_ethernet_main ();
 473   dhcp_proxy_main_t *dpm = &dhcp_proxy_main;
 474   vnet_main_t *vnm = vnet_get_main ();
 475   ip4_main_t *im = &ip4_main;
 476
 477   from = vlib_frame_vector_args (from_frame);
 478   n_left_from = from_frame->n_vectors;
 479
 480   while (n_left_from > 0)
 481     {
 482       u32 bi0;
 483       vlib_buffer_t *b0;
 484       udp_header_t *u0;
 485       dhcp_header_t *h0;
 486       ip4_header_t *ip0 = 0;
 487       ip4_address_t *ia0 = 0;
 488       u32 old0, new0;
 489       ip_csum_t sum0;
 490       ethernet_interface_t *ei0;
 491       ethernet_header_t *mac0;
 492       vnet_hw_interface_t *hi0;
 493       vlib_frame_t *f0;
 494       u32 *to_next0;
 495       u32 sw_if_index = ~0;
 496       vnet_sw_interface_t *si0;
 497       u32 error0 = (u32) ~ 0;
 498       vnet_sw_interface_t *swif;
 499       u32 fib_index;
 500       dhcp_proxy_t *proxy;
 501       dhcp_server_t *server;
 502       u32 original_sw_if_index = (u32) ~ 0;
 503       ip4_address_t relay_addr = {
 504         .as_u32 = 0,
 505       };
 506
 507       bi0 = from[0];
 508       from += 1;
 509       n_left_from -= 1;
 510
 511       b0 = vlib_get_buffer (vm, bi0);
 512       h0 = vlib_buffer_get_current (b0);
 513
 514       /*
 515        * udp_local hands us the DHCP header, need udp hdr,
 516        * ip hdr to relay to client
 517        */
 518       vlib_buffer_advance (b0, -(sizeof (*u0)));
 519       u0 = vlib_buffer_get_current (b0);
 520
 521       vlib_buffer_advance (b0, -(sizeof (*ip0)));
 522       ip0 = vlib_buffer_get_current (b0);
 523
 524       /* Consumed by dhcp client code? */
 525       if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
 526         continue;
 527
 528       if (1 /* dpm->insert_option_82 */ )
 529         {
 530           /* linearize needed to "unclone" and scan options */
 531           int space_left = vlib_buffer_chain_linearize (vm, b0);
 532           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 || space_left < 0)
 533             {
 534               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
 535               goto drop_packet;
 536             }
 537
 538           dhcp_option_t *o = h0->options, *end =
 539             (void *) vlib_buffer_get_tail (b0);
 540
 541           /* Parse through TLVs looking for option 82.
 542              The circuit-ID is the FIB number we need
 543              to track down the client-facing interface */
 544
 545           while (o->option != DHCP_PACKET_OPTION_END && o < end)
 546             {
 547               if (o->option == 82)
 548                 {
 549                   u32 vss_exist = 0;
 550                   u32 vss_ctrl = 0;
 551                   dhcp_option_t *sub = (dhcp_option_t *) & o->data[0];
 552                   dhcp_option_t *subend =
 553                     (dhcp_option_t *) (o->data + o->length);
 554                   while (sub->option != DHCP_PACKET_OPTION_END
 555                          && sub < subend)
 556                     {
 557                       /* If this is one of ours, it will have
 558                          total length 12, circuit-id suboption type,
 559                          and the sw_if_index */
 560                       if (sub->option == 1 && sub->length == 4)
 561                         {
 562                           sw_if_index = ((sub->data[0] << 24) |
 563                                          (sub->data[1] << 16) |
 564                                          (sub->data[2] << 8) |
 565                                          (sub->data[3]));
 566                         }
 567                       else if (sub->option == 5 && sub->length == 4)
 568                         {
 569                           relay_addr.as_u8[0] = sub->data[0];
 570                           relay_addr.as_u8[1] = sub->data[1];
 571                           relay_addr.as_u8[2] = sub->data[2];
 572                           relay_addr.as_u8[3] = sub->data[3];
 573                         }
 574                       else if (sub->option == 151 &&
 575                                sub->length == 7 && sub->data[0] == 1)
 576                         vss_exist = 1;
 577                       else if (sub->option == 152 && sub->length == 0)
 578                         vss_ctrl = 1;
 579                       sub = (dhcp_option_t *) (sub->data + sub->length);
 580                     }
 581                   if (vss_ctrl && vss_exist)
 582                     vlib_node_increment_counter
 583                       (vm, dhcp_proxy_to_client_node.index,
 584                        DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 585
 586                 }
 587               o = (dhcp_option_t *) (o->data + o->length);
 588             }
 589         }
 590
 591       if (sw_if_index == (u32) ~ 0)
 592         {
 593           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 594
 595         drop_packet:
 596           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 597                                        error0, 1);
 598           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 599           to_next0 = vlib_frame_vector_args (f0);
 600           to_next0[0] = bi0;
 601           f0->n_vectors = 1;
 602           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 603           goto do_trace;
 604         }
 605
 606       if (relay_addr.as_u32 == 0)
 607         {
 608           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ADDR;
 609           goto drop_packet;
 610         }
 611
 612       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 613         {
 614           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ITF;
 615           goto drop_packet;
 616         }
 617
 618       fib_index = im->fib_index_by_sw_if_index[sw_if_index];
 619       proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
 620
 621       if (PREDICT_FALSE (NULL == proxy))
 622         {
 623           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 624           goto drop_packet;
 625         }
 626
 627       vec_foreach (server, proxy->dhcp_servers)
 628       {
 629         if (ip0->src_address.as_u32 == server->dhcp_server.ip4.as_u32)
 630           {
 631             goto server_found;
 632           }
 633       }
 634
 635       error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 636       goto drop_packet;
 637
 638     server_found:
 639       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 640
 641       swif = vnet_get_sw_interface (vnm, sw_if_index);
 642       original_sw_if_index = sw_if_index;
 643       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 644         sw_if_index = swif->unnumbered_sw_if_index;
 645
 646       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 647       if (ia0 == 0)
 648         {
 649           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 650           goto drop_packet;
 651         }
 652
 653       if (relay_addr.as_u32 != ia0->as_u32)
 654         {
 655           error0 = DHCP_PROXY_ERROR_BAD_YIADDR;
 656           goto drop_packet;
 657         }
 658
 659       u0->checksum = 0;
 660       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 661       sum0 = ip0->checksum;
 662       old0 = ip0->dst_address.as_u32;
 663       new0 = 0xFFFFFFFF;
 664       ip0->dst_address.as_u32 = new0;
 665       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 666                              dst_address /* offset of changed member */ );
 667       ip0->checksum = ip_csum_fold (sum0);
 668
 669       sum0 = ip0->checksum;
 670       old0 = ip0->src_address.as_u32;
 671       new0 = ia0->as_u32;
 672       ip0->src_address.as_u32 = new0;
 673       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 674                              src_address /* offset of changed member */ );
 675       ip0->checksum = ip_csum_fold (sum0);
 676
 677       vlib_buffer_advance (b0, -(sizeof (ethernet_header_t)));
 678       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 679       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 680         vlib_buffer_advance (b0, -4 /* space for VLAN tag */ );
 681
 682       mac0 = vlib_buffer_get_current (b0);
 683
 684       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 685       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 686       clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 687       clib_memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 688       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 689         clib_net_to_host_u16 (0x8100) : clib_net_to_host_u16 (0x0800);
 690
 691       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 692         {
 693           u32 *vlan_tag = (u32 *) (mac0 + 1);
 694           u32 tmp;
 695           tmp = (si0->sub.id << 16) | 0x0800;
 696           *vlan_tag = clib_host_to_net_u32 (tmp);
 697         }
 698
 699       /* $$$ This needs to be rewritten, for sure */
 700       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 701       to_next0 = vlib_frame_vector_args (f0);
 702       to_next0[0] = bi0;
 703       f0->n_vectors = 1;
 704       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 705
 706     do_trace:
 707       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 708         {
 709           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 710                                                    b0, sizeof (*tr));
 711           tr->which = 1;        /* to client */
 712           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 713           tr->error = error0;
 714           tr->original_sw_if_index = original_sw_if_index;
 715           tr->sw_if_index = sw_if_index;
 716         }
 717     }
 718
 719   return from_frame->n_vectors;
 720 }
 721
 722 /* *INDENT-OFF* */
 723 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node, static) = {
 724   .function = dhcp_proxy_to_client_input,
 725   .name = "dhcp-proxy-to-client",
 726   /* Takes a vector of packets. */
 727   .vector_size = sizeof (u32),
 728
 729   .n_errors = DHCP_PROXY_N_ERROR,
 730   .error_strings = dhcp_proxy_error_strings,
 731   .format_buffer = format_dhcp_proxy_header_with_length,
 732   .format_trace = format_dhcp_proxy_trace,
 733 #if 0
 734   .unformat_buffer = unformat_dhcp_proxy_header,
 735 #endif
 736 };
 737 /* *INDENT-ON* */
 738
 739 void
 740 dhcp_maybe_register_udp_ports (void)
 741 {
 742   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 743   vlib_main_t *vm = dm->vlib_main;
 744
 745   if (dm->udp_ports_registered)
 746     return;
 747
 748   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
 749                          dhcp_proxy_to_client_node.index, 1 /* is_ip4 */ );
 750
 751   udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
 752                          dhcp_proxy_to_server_node.index, 1 /* is_ip4 */ );
 753
 754   dm->udp_ports_registered = 1;
 755 }
 756
 757 static clib_error_t *
 758 dhcp4_proxy_init (vlib_main_t * vm)
 759 {
 760   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 761   vlib_node_t *error_drop_node;
 762
 763   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 764   dm->error_drop_node_index = error_drop_node->index;
 765   dm->vlib_main = vm;
 766
 767   return 0;
 768 }
 769
 770
 771 VLIB_INIT_FUNCTION (dhcp4_proxy_init);
 772
 773 int
 774 dhcp4_proxy_set_server (ip46_address_t * addr,
 775                         ip46_address_t * src_addr,
 776                         u32 rx_table_id, u32 server_table_id, int is_del)
 777 {
 778   u32 rx_fib_index = 0;
 779   int rc = 0;
 780
 781   const fib_prefix_t all_1s = {
 782     .fp_len = 32,
 783     .fp_addr.ip4.as_u32 = 0xffffffff,
 784     .fp_proto = FIB_PROTOCOL_IP4,
 785   };
 786
 787   if (ip46_address_is_zero (addr))
 788     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 789
 790   if (ip46_address_is_zero (src_addr))
 791     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 792
 793   dhcp_maybe_register_udp_ports ();
 794
 795   rx_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 796                                                     rx_table_id,
 797                                                     FIB_SOURCE_DHCP);
 798
 799   if (is_del)
 800     {
 801       if (dhcp_proxy_server_del (FIB_PROTOCOL_IP4, rx_fib_index,
 802                                  addr, server_table_id))
 803         {
 804           fib_table_entry_special_remove (rx_fib_index,
 805                                           &all_1s, FIB_SOURCE_DHCP);
 806           fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 807         }
 808     }
 809   else
 810     {
 811       if (dhcp_proxy_server_add (FIB_PROTOCOL_IP4,
 812                                  addr, src_addr,
 813                                  rx_fib_index, server_table_id))
 814         {
 815           fib_table_entry_special_add (rx_fib_index,
 816                                        &all_1s,
 817                                        FIB_SOURCE_DHCP, FIB_ENTRY_FLAG_LOCAL);
 818           fib_table_lock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 819         }
 820     }
 821   fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 822
 823   return (rc);
 824 }
 825
 826 static clib_error_t *
 827 dhcp4_proxy_set_command_fn (vlib_main_t * vm,
 828                             unformat_input_t * input,
 829                             vlib_cli_command_t * cmd)
 830 {
 831   ip46_address_t server_addr, src_addr;
 832   u32 server_table_id = 0, rx_table_id = 0;
 833   int is_del = 0;
 834   int set_src = 0, set_server = 0;
 835
 836   clib_memset (&server_addr, 0, sizeof (server_addr));
 837   clib_memset (&src_addr, 0, sizeof (src_addr));
 838
 839   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 840     {
 841       if (unformat (input, "server %U",
 842                     unformat_ip4_address, &server_addr.ip4))
 843         set_server = 1;
 844       else if (unformat (input, "server-fib-id %d", &server_table_id))
 845         ;
 846       else if (unformat (input, "rx-fib-id %d", &rx_table_id))
 847         ;
 848       else if (unformat (input, "src-address %U",
 849                          unformat_ip4_address, &src_addr.ip4))
 850         set_src = 1;
 851       else if (unformat (input, "delete") || unformat (input, "del"))
 852         is_del = 1;
 853       else
 854         break;
 855     }
 856
 857   if (is_del || (set_server && set_src))
 858     {
 859       int rv;
 860
 861       rv = dhcp4_proxy_set_server (&server_addr, &src_addr, rx_table_id,
 862                                    server_table_id, is_del);
 863       switch (rv)
 864         {
 865         case 0:
 866           return 0;
 867
 868         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 869           return clib_error_return (0, "Invalid server address");
 870
 871         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 872           return clib_error_return (0, "Invalid src address");
 873
 874         case VNET_API_ERROR_NO_SUCH_ENTRY:
 875           return clib_error_return
 876             (0, "Fib id %d: no per-fib DHCP server configured", rx_table_id);
 877
 878         default:
 879           return clib_error_return (0, "BUG: rv %d", rv);
 880         }
 881     }
 882   else
 883     return clib_error_return (0, "parse error`%U'",
 884                               format_unformat_error, input);
 885 }
 886
 887 /* *INDENT-OFF* */
 888 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 889   .path = "set dhcp proxy",
 890   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [server-fib-id <n>] [rx-fib-id <n>]",
 891   .function = dhcp4_proxy_set_command_fn,
 892 };
 893 /* *INDENT-ON* */
 894
 895 static u8 *
 896 format_dhcp4_proxy_server (u8 * s, va_list * args)
 897 {
 898   dhcp_proxy_t *proxy = va_arg (*args, dhcp_proxy_t *);
 899   ip4_fib_t *rx_fib, *server_fib;
 900   dhcp_server_t *server;
 901
 902   if (proxy == 0)
 903     {
 904       s = format (s, "%=14s%=16s%s", "RX FIB", "Src Address",
 905                   "Servers FIB,Address");
 906       return s;
 907     }
 908
 909   rx_fib = ip4_fib_get (proxy->rx_fib_index);
 910
 911   s = format (s, "%=14u%=16U",
 912               rx_fib->table_id,
 913               format_ip46_address, &proxy->dhcp_src_address, IP46_TYPE_ANY);
 914
 915   vec_foreach (server, proxy->dhcp_servers)
 916   {
 917     server_fib = ip4_fib_get (server->server_fib_index);
 918     s = format (s, "%u,%U  ",
 919                 server_fib->table_id,
 920                 format_ip46_address, &server->dhcp_server, IP46_TYPE_ANY);
 921   }
 922   return s;
 923 }
 924
 925 static int
 926 dhcp4_proxy_show_walk (dhcp_proxy_t * server, void *ctx)
 927 {
 928   vlib_main_t *vm = ctx;
 929
 930   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, server);
 931
 932   return (1);
 933 }
 934
 935 static clib_error_t *
 936 dhcp4_proxy_show_command_fn (vlib_main_t * vm,
 937                              unformat_input_t * input,
 938                              vlib_cli_command_t * cmd)
 939 {
 940   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server,
 941                    NULL /* header line */ );
 942
 943   dhcp_proxy_walk (FIB_PROTOCOL_IP4, dhcp4_proxy_show_walk, vm);
 944
 945   return (NULL);
 946 }
 947
 948 /* *INDENT-OFF* */
 949 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 950   .path = "show dhcp proxy",
 951   .short_help = "Display dhcp proxy server info",
 952   .function = dhcp4_proxy_show_command_fn,
 953 };
 954 /* *INDENT-ON* */
 955
 956 static clib_error_t *
 957 dhcp_option_82_vss_fn (vlib_main_t * vm,
 958                        unformat_input_t * input, vlib_cli_command_t * cmd)
 959 {
 960   u8 is_del = 0, vss_type = VSS_TYPE_DEFAULT;
 961   u32 oui = 0, fib_id = 0, tbl_id = ~0;
 962   u8 *vpn_ascii_id = 0;
 963
 964   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 965     {
 966       if (unformat (input, "table %d", &tbl_id))
 967         ;
 968       else if (unformat (input, "oui %d", &oui))
 969         vss_type = VSS_TYPE_VPN_ID;
 970       else if (unformat (input, "vpn-id %d", &fib_id))
 971         vss_type = VSS_TYPE_VPN_ID;
 972       else if (unformat (input, "vpn-ascii-id %s", &vpn_ascii_id))
 973         vss_type = VSS_TYPE_ASCII;
 974       else if (unformat (input, "delete") || unformat (input, "del"))
 975         is_del = 1;
 976       else
 977         break;
 978     }
 979
 980   if (tbl_id == ~0)
 981     return clib_error_return (0, "no table ID specified.");
 982
 983   int rv = dhcp_proxy_set_vss (FIB_PROTOCOL_IP4, tbl_id, vss_type,
 984                                vpn_ascii_id, oui, fib_id, is_del);
 985   switch (rv)
 986     {
 987     case 0:
 988       return 0;
 989     case VNET_API_ERROR_NO_SUCH_ENTRY:
 990       return clib_error_return (0,
 991                                 "option 82 vss for table %d not found in in pool.",
 992                                 tbl_id);
 993     default:
 994       return clib_error_return (0, "BUG: rv %d", rv);
 995
 996     }
 997 }
 998
 999 /* *INDENT-OFF* */
1000 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
1001   .path = "set dhcp option-82 vss",
1002   .short_help = "set dhcp option-82 vss [del] table <table id> [oui <n> vpn-id <n> | vpn-ascii-id <text>]",
1003   .function = dhcp_option_82_vss_fn,
1004 };
1005 /* *INDENT-ON* */
1006
1007 static clib_error_t *
1008 dhcp_vss_show_command_fn (vlib_main_t * vm,
1009                           unformat_input_t * input, vlib_cli_command_t * cmd)
1010 {
1011   dhcp_vss_walk (FIB_PROTOCOL_IP4, dhcp_vss_show_walk, vm);
1012
1013   return (NULL);
1014 }
1015
1016 /* *INDENT-OFF* */
1017 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1018   .path = "show dhcp vss",
1019   .short_help = "show dhcp VSS",
1020   .function = dhcp_vss_show_command_fn,
1021 };
1022 /* *INDENT-ON* */
1023
1024 static clib_error_t *
1025 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1026                                         unformat_input_t * input,
1027                                         vlib_cli_command_t * cmd)
1028 {
1029   vnet_main_t *vnm = vnet_get_main ();
1030   u32 sw_if_index0 = 0, sw_if_index;
1031   vnet_sw_interface_t *swif;
1032   ip4_address_t *ia0;
1033
1034   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
1035     {
1036
1037       if (unformat (input, "%U",
1038                     unformat_vnet_sw_interface, vnm, &sw_if_index0))
1039         {
1040           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1041           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1042             swif->unnumbered_sw_if_index : sw_if_index0;
1043           ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
1044           if (ia0)
1045             {
1046               vlib_cli_output (vm, "%=20s%=20s", "interface",
1047                                "source IP address");
1048
1049               vlib_cli_output (vm, "%=20U%=20U",
1050                                format_vnet_sw_if_index_name,
1051                                vnm, sw_if_index0, format_ip4_address, ia0);
1052             }
1053           else
1054             vlib_cli_output (vm, "%=34s %=20U",
1055                              "No IPv4 address configured on",
1056                              format_vnet_sw_if_index_name, vnm, sw_if_index);
1057         }
1058       else
1059         break;
1060     }
1061
1062   return 0;
1063 }
1064
1065 /* *INDENT-OFF* */
1066 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1067   .path = "show dhcp option-82-address interface",
1068   .short_help = "show dhcp option-82-address interface <interface>",
1069   .function = dhcp_option_82_address_show_command_fn,
1070 };
1071 /* *INDENT-ON* */
1072
1073 /*
1074  * fd.io coding-style-patch-verification: ON
1075  *
1076  * Local Variables:
1077  * eval: (c-set-style "gnu")
1078  * End:
1079  */