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           u8 *end = NULL;
 138           u32 fib_index;
 139           dhcp_proxy_t *proxy;
 140           dhcp_server_t *server;
 141           u32 rx_sw_if_index;
 142           dhcp_option_t *o;
 143           u32 len = 0;
 144           vlib_buffer_free_list_t *fl;
 145           u8 is_discover = 0;
 146
 147           bi0 = from[0];
 148           from += 1;
 149           n_left_from -= 1;
 150
 151           b0 = vlib_get_buffer (vm, bi0);
 152
 153           h0 = vlib_buffer_get_current (b0);
 154
 155           /*
 156            * udp_local hands us the DHCP header, need udp hdr,
 157            * ip hdr to relay to server
 158            */
 159           vlib_buffer_advance (b0, -(sizeof (*u0)));
 160           u0 = vlib_buffer_get_current (b0);
 161
 162           /* This blows. Return traffic has src_port = 67, dst_port = 67 */
 163           if (u0->src_port ==
 164               clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_server))
 165             {
 166               vlib_buffer_advance (b0, sizeof (*u0));
 167               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
 168               error0 = 0;
 169               pkts_to_client++;
 170               goto do_enqueue;
 171             }
 172
 173           rx_sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
 174
 175           fib_index = im->fib_index_by_sw_if_index[rx_sw_if_index];
 176           proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
 177
 178           if (PREDICT_FALSE (NULL == proxy))
 179             {
 180               error0 = DHCP_PROXY_ERROR_NO_SERVER;
 181               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 182               pkts_no_server++;
 183               goto do_trace;
 184             }
 185
 186           server = &proxy->dhcp_servers[0];
 187           vlib_buffer_advance (b0, -(sizeof (*ip0)));
 188           ip0 = vlib_buffer_get_current (b0);
 189
 190           /* disable UDP checksum */
 191           u0->checksum = 0;
 192           sum0 = ip0->checksum;
 193           old0 = ip0->dst_address.as_u32;
 194           new0 = server->dhcp_server.ip4.as_u32;
 195           ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 196           sum0 = ip_csum_update (sum0, old0, new0,
 197                                  ip4_header_t /* structure */ ,
 198                                  dst_address /* changed member */ );
 199           ip0->checksum = ip_csum_fold (sum0);
 200
 201           sum0 = ip0->checksum;
 202           old0 = ip0->src_address.as_u32;
 203           new0 = proxy->dhcp_src_address.ip4.as_u32;
 204           ip0->src_address.as_u32 = new0;
 205           sum0 = ip_csum_update (sum0, old0, new0,
 206                                  ip4_header_t /* structure */ ,
 207                                  src_address /* changed member */ );
 208           ip0->checksum = ip_csum_fold (sum0);
 209
 210           /* Send to DHCP server via the configured FIB */
 211           vnet_buffer (b0)->sw_if_index[VLIB_TX] = server->server_fib_index;
 212
 213           h0->gateway_ip_address.as_u32 = proxy->dhcp_src_address.ip4.as_u32;
 214           pkts_to_server++;
 215
 216           o = (dhcp_option_t *) h0->options;
 217
 218           fib_index = im->fib_index_by_sw_if_index
 219             [vnet_buffer (b0)->sw_if_index[VLIB_RX]];
 220
 221           end = b0->data + b0->current_data + b0->current_length;
 222           /* TLVs are not performance-friendly... */
 223           while (o->option != 0xFF /* end of options */  && (u8 *) o < end)
 224             {
 225               if (DHCP_PACKET_OPTION_MSG_TYPE == o->option)
 226                 {
 227                   if (DHCP_PACKET_DISCOVER == o->data[0])
 228                     {
 229                       is_discover = 1;
 230                     }
 231                 }
 232               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 233             }
 234
 235           fl =
 236             vlib_buffer_get_free_list (vm,
 237                                        vlib_buffer_get_free_list_index (b0));
 238           // start write at (option*)o, some packets have padding
 239           if (((u8 *) o - (u8 *) b0->data + VPP_DHCP_OPTION82_SIZE) >
 240               fl->n_data_bytes)
 241             {
 242               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
 243               pkts_too_big++;
 244               goto do_trace;
 245             }
 246
 247           if ((o->option == 0xFF) && ((u8 *) o <= end))
 248             {
 249               vnet_main_t *vnm = vnet_get_main ();
 250               u16 old_l0, new_l0;
 251               ip4_address_t _ia0, *ia0 = &_ia0;
 252               dhcp_vss_t *vss;
 253               vnet_sw_interface_t *swif;
 254               sw_if_index = 0;
 255               original_sw_if_index = 0;
 256
 257               original_sw_if_index = sw_if_index =
 258                 vnet_buffer (b0)->sw_if_index[VLIB_RX];
 259               swif = vnet_get_sw_interface (vnm, sw_if_index);
 260               if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 261                 sw_if_index = swif->unnumbered_sw_if_index;
 262
 263               /*
 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] = 0xFF;
 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] = 0xFF;  /* "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                   ci0 = vlib_get_buffer_index (vm, c0);
 362                   server = &proxy->dhcp_servers[ii];
 363
 364                   ip0 = vlib_buffer_get_current (c0);
 365
 366                   sum0 = ip0->checksum;
 367                   old0 = ip0->dst_address.as_u32;
 368                   new0 = server->dhcp_server.ip4.as_u32;
 369                   ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
 370                   sum0 = ip_csum_update (sum0, old0, new0,
 371                                          ip4_header_t /* structure */ ,
 372                                          dst_address /* changed member */ );
 373                   ip0->checksum = ip_csum_fold (sum0);
 374
 375                   to_next[0] = ci0;
 376                   to_next += 1;
 377                   n_left_to_next -= 1;
 378
 379                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 380                                                    to_next, n_left_to_next,
 381                                                    ci0, next0);
 382
 383                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 384                     {
 385                       dhcp_proxy_trace_t *tr;
 386
 387                       tr = vlib_add_trace (vm, node, c0, sizeof (*tr));
 388                       tr->which = 0;    /* to server */
 389                       tr->error = error0;
 390                       tr->original_sw_if_index = original_sw_if_index;
 391                       tr->sw_if_index = sw_if_index;
 392                       if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 393                         tr->trace_ip4_address.as_u32 =
 394                           server->dhcp_server.ip4.as_u32;
 395                     }
 396
 397                   if (PREDICT_FALSE (0 == n_left_to_next))
 398                     {
 399                       vlib_put_next_frame (vm, node, next_index,
 400                                            n_left_to_next);
 401                       vlib_get_next_frame (vm, node, next_index,
 402                                            to_next, n_left_to_next);
 403                     }
 404                 }
 405             }
 406         do_trace:
 407           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 408             {
 409               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 410                                                        b0, sizeof (*tr));
 411               tr->which = 0;    /* to server */
 412               tr->error = error0;
 413               tr->original_sw_if_index = original_sw_if_index;
 414               tr->sw_if_index = sw_if_index;
 415               if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
 416                 tr->trace_ip4_address.as_u32 =
 417                   proxy->dhcp_servers[0].dhcp_server.ip4.as_u32;
 418             }
 419
 420         do_enqueue:
 421           to_next[0] = bi0;
 422           to_next += 1;
 423           n_left_to_next -= 1;
 424
 425           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 426                                            to_next, n_left_to_next,
 427                                            bi0, next0);
 428         }
 429
 430       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 431     }
 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           dhcp_option_t *o = (dhcp_option_t *) h0->options;
 539           dhcp_option_t *sub;
 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 != 0xFF /* end of options */  &&
 546                  (u8 *) o <
 547                  (b0->data + b0->current_data + b0->current_length))
 548             {
 549               if (o->option == 82)
 550                 {
 551                   u32 vss_exist = 0;
 552                   u32 vss_ctrl = 0;
 553                   sub = (dhcp_option_t *) & o->data[0];
 554                   while (sub->option != 0xFF /* end of options */  &&
 555                          (u8 *) sub < (u8 *) (o + o->length))
 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 *)
 580                         (((uword) sub) + (sub->length + 2));
 581                     }
 582                   if (vss_ctrl && vss_exist)
 583                     vlib_node_increment_counter
 584                       (vm, dhcp_proxy_to_client_node.index,
 585                        DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
 586
 587                 }
 588               o = (dhcp_option_t *) (((uword) o) + (o->length + 2));
 589             }
 590         }
 591
 592       if (sw_if_index == (u32) ~ 0)
 593         {
 594           error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
 595
 596         drop_packet:
 597           vlib_node_increment_counter (vm, dhcp_proxy_to_client_node.index,
 598                                        error0, 1);
 599           f0 = vlib_get_frame_to_node (vm, dpm->error_drop_node_index);
 600           to_next0 = vlib_frame_vector_args (f0);
 601           to_next0[0] = bi0;
 602           f0->n_vectors = 1;
 603           vlib_put_frame_to_node (vm, dpm->error_drop_node_index, f0);
 604           goto do_trace;
 605         }
 606
 607       if (relay_addr.as_u32 == 0)
 608         {
 609           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ADDR;
 610           goto drop_packet;
 611         }
 612
 613       if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
 614         {
 615           error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ITF;
 616           goto drop_packet;
 617         }
 618
 619       fib_index = im->fib_index_by_sw_if_index[sw_if_index];
 620       proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
 621
 622       if (PREDICT_FALSE (NULL == proxy))
 623         {
 624           error0 = DHCP_PROXY_ERROR_NO_SERVER;
 625           goto drop_packet;
 626         }
 627
 628       vec_foreach (server, proxy->dhcp_servers)
 629       {
 630         if (ip0->src_address.as_u32 == server->dhcp_server.ip4.as_u32)
 631           {
 632             goto server_found;
 633           }
 634       }
 635
 636       error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
 637       goto drop_packet;
 638
 639     server_found:
 640       vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
 641
 642       swif = vnet_get_sw_interface (vnm, sw_if_index);
 643       original_sw_if_index = sw_if_index;
 644       if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
 645         sw_if_index = swif->unnumbered_sw_if_index;
 646
 647       ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
 648       if (ia0 == 0)
 649         {
 650           error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
 651           goto drop_packet;
 652         }
 653
 654       if (relay_addr.as_u32 != ia0->as_u32)
 655         {
 656           error0 = DHCP_PROXY_ERROR_BAD_YIADDR;
 657           goto drop_packet;
 658         }
 659
 660       u0->checksum = 0;
 661       u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
 662       sum0 = ip0->checksum;
 663       old0 = ip0->dst_address.as_u32;
 664       new0 = 0xFFFFFFFF;
 665       ip0->dst_address.as_u32 = new0;
 666       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 667                              dst_address /* offset of changed member */ );
 668       ip0->checksum = ip_csum_fold (sum0);
 669
 670       sum0 = ip0->checksum;
 671       old0 = ip0->src_address.as_u32;
 672       new0 = ia0->as_u32;
 673       ip0->src_address.as_u32 = new0;
 674       sum0 = ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
 675                              src_address /* offset of changed member */ );
 676       ip0->checksum = ip_csum_fold (sum0);
 677
 678       vlib_buffer_advance (b0, -(sizeof (ethernet_header_t)));
 679       si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
 680       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 681         vlib_buffer_advance (b0, -4 /* space for VLAN tag */ );
 682
 683       mac0 = vlib_buffer_get_current (b0);
 684
 685       hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
 686       ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
 687       clib_memcpy (mac0->src_address, ei0->address, sizeof (ei0->address));
 688       memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
 689       mac0->type = (si0->type == VNET_SW_INTERFACE_TYPE_SUB) ?
 690         clib_net_to_host_u16 (0x8100) : clib_net_to_host_u16 (0x0800);
 691
 692       if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
 693         {
 694           u32 *vlan_tag = (u32 *) (mac0 + 1);
 695           u32 tmp;
 696           tmp = (si0->sub.id << 16) | 0x0800;
 697           *vlan_tag = clib_host_to_net_u32 (tmp);
 698         }
 699
 700       /* $$$ This needs to be rewritten, for sure */
 701       f0 = vlib_get_frame_to_node (vm, hi0->output_node_index);
 702       to_next0 = vlib_frame_vector_args (f0);
 703       to_next0[0] = bi0;
 704       f0->n_vectors = 1;
 705       vlib_put_frame_to_node (vm, hi0->output_node_index, f0);
 706
 707     do_trace:
 708       if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
 709         {
 710           dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
 711                                                    b0, sizeof (*tr));
 712           tr->which = 1;        /* to client */
 713           tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
 714           tr->error = error0;
 715           tr->original_sw_if_index = original_sw_if_index;
 716           tr->sw_if_index = sw_if_index;
 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 static clib_error_t *
 740 dhcp4_proxy_init (vlib_main_t * vm)
 741 {
 742   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
 743   vlib_node_t *error_drop_node;
 744
 745   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
 746   dm->error_drop_node_index = error_drop_node->index;
 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   return 0;
 755 }
 756
 757
 758 VLIB_INIT_FUNCTION (dhcp4_proxy_init);
 759
 760 int
 761 dhcp4_proxy_set_server (ip46_address_t * addr,
 762                         ip46_address_t * src_addr,
 763                         u32 rx_table_id, u32 server_table_id, int is_del)
 764 {
 765   u32 rx_fib_index = 0;
 766   int rc = 0;
 767
 768   const fib_prefix_t all_1s = {
 769     .fp_len = 32,
 770     .fp_addr.ip4.as_u32 = 0xffffffff,
 771     .fp_proto = FIB_PROTOCOL_IP4,
 772   };
 773
 774   if (ip46_address_is_zero (addr))
 775     return VNET_API_ERROR_INVALID_DST_ADDRESS;
 776
 777   if (ip46_address_is_zero (src_addr))
 778     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
 779
 780   rx_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 781                                                     rx_table_id,
 782                                                     FIB_SOURCE_DHCP);
 783
 784   if (is_del)
 785     {
 786       if (dhcp_proxy_server_del (FIB_PROTOCOL_IP4, rx_fib_index,
 787                                  addr, server_table_id))
 788         {
 789           fib_table_entry_special_remove (rx_fib_index,
 790                                           &all_1s, FIB_SOURCE_DHCP);
 791           fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 792         }
 793     }
 794   else
 795     {
 796       if (dhcp_proxy_server_add (FIB_PROTOCOL_IP4,
 797                                  addr, src_addr,
 798                                  rx_fib_index, server_table_id))
 799         {
 800           fib_table_entry_special_add (rx_fib_index,
 801                                        &all_1s,
 802                                        FIB_SOURCE_DHCP, FIB_ENTRY_FLAG_LOCAL);
 803           fib_table_lock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 804         }
 805     }
 806   fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
 807
 808   return (rc);
 809 }
 810
 811 static clib_error_t *
 812 dhcp4_proxy_set_command_fn (vlib_main_t * vm,
 813                             unformat_input_t * input,
 814                             vlib_cli_command_t * cmd)
 815 {
 816   ip46_address_t server_addr, src_addr;
 817   u32 server_table_id = 0, rx_table_id = 0;
 818   int is_del = 0;
 819   int set_src = 0, set_server = 0;
 820
 821   memset (&server_addr, 0, sizeof (server_addr));
 822   memset (&src_addr, 0, sizeof (src_addr));
 823
 824   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 825     {
 826       if (unformat (input, "server %U",
 827                     unformat_ip4_address, &server_addr.ip4))
 828         set_server = 1;
 829       else if (unformat (input, "server-fib-id %d", &server_table_id))
 830         ;
 831       else if (unformat (input, "rx-fib-id %d", &rx_table_id))
 832         ;
 833       else if (unformat (input, "src-address %U",
 834                          unformat_ip4_address, &src_addr.ip4))
 835         set_src = 1;
 836       else if (unformat (input, "delete") || unformat (input, "del"))
 837         is_del = 1;
 838       else
 839         break;
 840     }
 841
 842   if (is_del || (set_server && set_src))
 843     {
 844       int rv;
 845
 846       rv = dhcp4_proxy_set_server (&server_addr, &src_addr, rx_table_id,
 847                                    server_table_id, is_del);
 848       switch (rv)
 849         {
 850         case 0:
 851           return 0;
 852
 853         case VNET_API_ERROR_INVALID_DST_ADDRESS:
 854           return clib_error_return (0, "Invalid server address");
 855
 856         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
 857           return clib_error_return (0, "Invalid src address");
 858
 859         case VNET_API_ERROR_NO_SUCH_ENTRY:
 860           return clib_error_return
 861             (0, "Fib id %d: no per-fib DHCP server configured", rx_table_id);
 862
 863         default:
 864           return clib_error_return (0, "BUG: rv %d", rv);
 865         }
 866     }
 867   else
 868     return clib_error_return (0, "parse error`%U'",
 869                               format_unformat_error, input);
 870 }
 871
 872 /* *INDENT-OFF* */
 873 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
 874   .path = "set dhcp proxy",
 875   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [server-fib-id <n>] [rx-fib-id <n>]",
 876   .function = dhcp4_proxy_set_command_fn,
 877 };
 878 /* *INDENT-ON* */
 879
 880 static u8 *
 881 format_dhcp4_proxy_server (u8 * s, va_list * args)
 882 {
 883   dhcp_proxy_t *proxy = va_arg (*args, dhcp_proxy_t *);
 884   ip4_fib_t *rx_fib, *server_fib;
 885   dhcp_server_t *server;
 886
 887   if (proxy == 0)
 888     {
 889       s = format (s, "%=14s%=16s%s", "RX FIB", "Src Address",
 890                   "Servers FIB,Address");
 891       return s;
 892     }
 893
 894   rx_fib = ip4_fib_get (proxy->rx_fib_index);
 895
 896   s = format (s, "%=14u%=16U",
 897               rx_fib->table_id,
 898               format_ip46_address, &proxy->dhcp_src_address, IP46_TYPE_ANY);
 899
 900   vec_foreach (server, proxy->dhcp_servers)
 901   {
 902     server_fib = ip4_fib_get (server->server_fib_index);
 903     s = format (s, "%u,%U  ",
 904                 server_fib->table_id,
 905                 format_ip46_address, &server->dhcp_server, IP46_TYPE_ANY);
 906   }
 907   return s;
 908 }
 909
 910 static int
 911 dhcp4_proxy_show_walk (dhcp_proxy_t * server, void *ctx)
 912 {
 913   vlib_main_t *vm = ctx;
 914
 915   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, server);
 916
 917   return (1);
 918 }
 919
 920 static clib_error_t *
 921 dhcp4_proxy_show_command_fn (vlib_main_t * vm,
 922                              unformat_input_t * input,
 923                              vlib_cli_command_t * cmd)
 924 {
 925   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server,
 926                    NULL /* header line */ );
 927
 928   dhcp_proxy_walk (FIB_PROTOCOL_IP4, dhcp4_proxy_show_walk, vm);
 929
 930   return (NULL);
 931 }
 932
 933 /* *INDENT-OFF* */
 934 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
 935   .path = "show dhcp proxy",
 936   .short_help = "Display dhcp proxy server info",
 937   .function = dhcp4_proxy_show_command_fn,
 938 };
 939 /* *INDENT-ON* */
 940
 941 static clib_error_t *
 942 dhcp_option_82_vss_fn (vlib_main_t * vm,
 943                        unformat_input_t * input, vlib_cli_command_t * cmd)
 944 {
 945   u8 is_del = 0, vss_type = VSS_TYPE_DEFAULT;
 946   u32 oui = 0, fib_id = 0, tbl_id = ~0;
 947   u8 *vpn_ascii_id = 0;
 948
 949   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
 950     {
 951       if (unformat (input, "table %d", &tbl_id))
 952         ;
 953       else if (unformat (input, "oui %d", &oui))
 954         vss_type = VSS_TYPE_VPN_ID;
 955       else if (unformat (input, "vpn-id %d", &fib_id))
 956         vss_type = VSS_TYPE_VPN_ID;
 957       else if (unformat (input, "vpn-ascii-id %s", &vpn_ascii_id))
 958         vss_type = VSS_TYPE_ASCII;
 959       else if (unformat (input, "delete") || unformat (input, "del"))
 960         is_del = 1;
 961       else
 962         break;
 963     }
 964
 965   if (tbl_id == ~0)
 966     return clib_error_return (0, "no table ID specified.");
 967
 968   int rv = dhcp_proxy_set_vss (FIB_PROTOCOL_IP4, tbl_id, vss_type,
 969                                vpn_ascii_id, oui, fib_id, is_del);
 970   switch (rv)
 971     {
 972     case 0:
 973       return 0;
 974     case VNET_API_ERROR_NO_SUCH_ENTRY:
 975       return clib_error_return (0,
 976                                 "option 82 vss for table %d not found in in pool.",
 977                                 tbl_id);
 978     default:
 979       return clib_error_return (0, "BUG: rv %d", rv);
 980
 981     }
 982 }
 983
 984 /* *INDENT-OFF* */
 985 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
 986   .path = "set dhcp option-82 vss",
 987   .short_help = "set dhcp option-82 vss [del] table <table id> [oui <n> vpn-id <n> | vpn-ascii-id <text>]",
 988   .function = dhcp_option_82_vss_fn,
 989 };
 990 /* *INDENT-ON* */
 991
 992 static clib_error_t *
 993 dhcp_vss_show_command_fn (vlib_main_t * vm,
 994                           unformat_input_t * input, vlib_cli_command_t * cmd)
 995 {
 996   dhcp_vss_walk (FIB_PROTOCOL_IP4, dhcp_vss_show_walk, vm);
 997
 998   return (NULL);
 999 }
1000
1001 /* *INDENT-OFF* */
1002 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1003   .path = "show dhcp vss",
1004   .short_help = "show dhcp VSS",
1005   .function = dhcp_vss_show_command_fn,
1006 };
1007 /* *INDENT-ON* */
1008
1009 static clib_error_t *
1010 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1011                                         unformat_input_t * input,
1012                                         vlib_cli_command_t * cmd)
1013 {
1014   vnet_main_t *vnm = vnet_get_main ();
1015   u32 sw_if_index0 = 0, sw_if_index;
1016   vnet_sw_interface_t *swif;
1017   ip4_address_t *ia0;
1018
1019   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
1020     {
1021
1022       if (unformat (input, "%U",
1023                     unformat_vnet_sw_interface, vnm, &sw_if_index0))
1024         {
1025           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1026           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1027             swif->unnumbered_sw_if_index : sw_if_index0;
1028           ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
1029           if (ia0)
1030             {
1031               vlib_cli_output (vm, "%=20s%=20s", "interface",
1032                                "source IP address");
1033
1034               vlib_cli_output (vm, "%=20U%=20U",
1035                                format_vnet_sw_if_index_name,
1036                                vnm, sw_if_index0, format_ip4_address, ia0);
1037             }
1038           else
1039             vlib_cli_output (vm, "%=34s %=20U",
1040                              "No IPv4 address configured on",
1041                              format_vnet_sw_if_index_name, vnm, sw_if_index);
1042         }
1043       else
1044         break;
1045     }
1046
1047   return 0;
1048 }
1049
1050 /* *INDENT-OFF* */
1051 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1052   .path = "show dhcp option-82-address interface",
1053   .short_help = "show dhcp option-82-address interface <interface>",
1054   .function = dhcp_option_82_address_show_command_fn,
1055 };
1056 /* *INDENT-ON* */
1057
1058 /*
1059  * fd.io coding-style-patch-verification: ON
1060  *
1061  * Local Variables:
1062  * eval: (c-set-style "gnu")
1063  * End:
1064  */