78c4444a1e8ef54bcdf77a94b257817bfb69f567
[vpp.git] / src / plugins / 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 <dhcp/dhcp_proxy.h>
21 #include <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 <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
52   /* enough space for the DHCP header plus some options */
53   u8 packet_data[2 * sizeof (dhcp_header_t)];
54 }
55 dhcp_proxy_trace_t;
56
57 #define VPP_DHCP_OPTION82_SUB1_SIZE   6
58 #define VPP_DHCP_OPTION82_SUB5_SIZE   6
59 #define VPP_DHCP_OPTION82_VSS_SIZE    12
60 #define VPP_DHCP_OPTION82_SIZE (VPP_DHCP_OPTION82_SUB1_SIZE + \
61                                 VPP_DHCP_OPTION82_SUB5_SIZE + \
62                                 VPP_DHCP_OPTION82_VSS_SIZE +3)
63
64 static vlib_node_registration_t dhcp_proxy_to_server_node;
65 static vlib_node_registration_t dhcp_proxy_to_client_node;
66
67 static u8 *
68 format_dhcp_proxy_trace (u8 * s, va_list * args)
69 {
70   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
71   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
72   dhcp_proxy_trace_t *t = va_arg (*args, dhcp_proxy_trace_t *);
73
74   if (t->which == 0)
75     s = format (s, "DHCP proxy: sent to server %U\n",
76                 format_ip4_address, &t->trace_ip4_address, t->error);
77   else
78     s = format (s, "DHCP proxy: broadcast to client from %U\n",
79                 format_ip4_address, &t->trace_ip4_address);
80
81   if (t->error != (u32) ~ 0)
82     s = format (s, "  error: %s\n", dhcp_proxy_error_strings[t->error]);
83
84   s = format (s, "  original_sw_if_index: %d, sw_if_index: %d\n",
85               t->original_sw_if_index, t->sw_if_index);
86   s = format (s, "  %U",
87               format_dhcp_header, t->packet_data, sizeof (t->packet_data));
88
89   return s;
90 }
91
92 static u8 *
93 format_dhcp_proxy_header_with_length (u8 * s, va_list * args)
94 {
95   dhcp_header_t *h = va_arg (*args, dhcp_header_t *);
96   u32 max_header_bytes = va_arg (*args, u32);
97   u32 header_bytes;
98
99   header_bytes = sizeof (h[0]);
100   if (max_header_bytes != 0 && header_bytes > max_header_bytes)
101     return format (s, "dhcp header truncated");
102
103   s = format (s, "DHCP Proxy");
104
105   return s;
106 }
107
108 static uword
109 dhcp_proxy_to_server_input (vlib_main_t * vm,
110                             vlib_node_runtime_t * node,
111                             vlib_frame_t * from_frame)
112 {
113   u32 n_left_from, next_index, *from, *to_next;
114   dhcp_proxy_main_t *dpm = &dhcp_proxy_main;
115   from = vlib_frame_vector_args (from_frame);
116   n_left_from = from_frame->n_vectors;
117   u32 pkts_to_server = 0, pkts_to_client = 0, pkts_no_server = 0;
118   u32 pkts_no_interface_address = 0;
119   u32 pkts_too_big = 0;
120   ip4_main_t *im = &ip4_main;
121
122   next_index = node->cached_next_index;
123
124   while (n_left_from > 0)
125     {
126       u32 n_left_to_next;
127
128       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
129
130       while (n_left_from > 0 && n_left_to_next > 0)
131         {
132           u32 bi0;
133           vlib_buffer_t *b0;
134           udp_header_t *u0;
135           dhcp_header_t *h0;
136           ip4_header_t *ip0;
137           u32 next0;
138           u32 old0, new0;
139           ip_csum_t sum0;
140           u32 error0 = (u32) ~ 0;
141           u32 sw_if_index = 0;
142           u32 original_sw_if_index = 0;
143           u32 fib_index;
144           dhcp_proxy_t *proxy;
145           dhcp_server_t *server;
146           u32 rx_sw_if_index;
147           dhcp_option_t *o, *end;
148           u32 len = 0;
149           u8 is_discover = 0;
150           int space_left;
151
152           bi0 = from[0];
153           from += 1;
154           n_left_from -= 1;
155
156           b0 = vlib_get_buffer (vm, bi0);
157
158           h0 = vlib_buffer_get_current (b0);
159
160           /*
161            * udp_local hands us the DHCP header, need udp hdr,
162            * ip hdr to relay to server
163            */
164           vlib_buffer_advance (b0, -(sizeof (*u0)));
165           u0 = vlib_buffer_get_current (b0);
166
167           /* This blows. Return traffic has src_port = 67, dst_port = 67 */
168           if (u0->src_port ==
169               clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_server))
170             {
171               vlib_buffer_advance (b0, sizeof (*u0));
172               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_SEND_TO_CLIENT;
173               error0 = 0;
174               pkts_to_client++;
175               goto do_enqueue;
176             }
177
178           rx_sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
179           fib_index = im->fib_index_by_sw_if_index[rx_sw_if_index];
180           proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
181
182           if (PREDICT_FALSE (NULL == proxy))
183             {
184               error0 = DHCP_PROXY_ERROR_NO_SERVER;
185               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
186               pkts_no_server++;
187               goto do_trace;
188             }
189
190           if (!vlib_buffer_chain_linearize (vm, b0))
191             {
192               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
193               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
194               pkts_too_big++;
195               goto do_trace;
196             }
197           space_left = vlib_buffer_space_left_at_end (vm, b0);
198           /* cant parse chains...
199            * and we need some space for option 82*/
200           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 ||
201               space_left < VPP_DHCP_OPTION82_SIZE)
202             {
203               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
204               next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
205               pkts_too_big++;
206               goto do_trace;
207             }
208
209           server = &proxy->dhcp_servers[0];
210           vlib_buffer_advance (b0, -(sizeof (*ip0)));
211           ip0 = vlib_buffer_get_current (b0);
212
213           /* disable UDP checksum */
214           u0->checksum = 0;
215           sum0 = ip0->checksum;
216           old0 = ip0->dst_address.as_u32;
217           new0 = server->dhcp_server.ip4.as_u32;
218           ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
219           sum0 = ip_csum_update (sum0, old0, new0,
220                                  ip4_header_t /* structure */ ,
221                                  dst_address /* changed member */ );
222           ip0->checksum = ip_csum_fold (sum0);
223
224           sum0 = ip0->checksum;
225           old0 = ip0->src_address.as_u32;
226           new0 = proxy->dhcp_src_address.ip4.as_u32;
227           ip0->src_address.as_u32 = new0;
228           sum0 = ip_csum_update (sum0, old0, new0,
229                                  ip4_header_t /* structure */ ,
230                                  src_address /* changed member */ );
231           ip0->checksum = ip_csum_fold (sum0);
232
233           /* Send to DHCP server via the configured FIB */
234           vnet_buffer (b0)->sw_if_index[VLIB_TX] = server->server_fib_index;
235
236           h0->gateway_ip_address = proxy->dhcp_src_address.ip4;
237           pkts_to_server++;
238
239           o = h0->options;
240           end = (void *) vlib_buffer_get_tail (b0);
241
242           /* TLVs are not performance-friendly... */
243           while (o->option != DHCP_PACKET_OPTION_END && o < end)
244             {
245               if (DHCP_PACKET_OPTION_MSG_TYPE == o->option)
246                 {
247                   if (DHCP_PACKET_DISCOVER == o->data[0])
248                     {
249                       is_discover = 1;
250                     }
251                 }
252               o = (dhcp_option_t *) (o->data + o->length);
253             }
254
255           if (o->option == DHCP_PACKET_OPTION_END && o <= end)
256             {
257               vnet_main_t *vnm = vnet_get_main ();
258               u16 old_l0, new_l0;
259               ip4_address_t _ia0, *ia0 = &_ia0;
260               dhcp_vss_t *vss;
261               vnet_sw_interface_t *swif;
262
263               original_sw_if_index = sw_if_index =
264                 vnet_buffer (b0)->sw_if_index[VLIB_RX];
265               swif = vnet_get_sw_interface (vnm, sw_if_index);
266               if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
267                 sw_if_index = swif->unnumbered_sw_if_index;
268
269               /*
270                * Get the first ip4 address on the [client-side]
271                * RX interface, if not unnumbered. otherwise use
272                * the loopback interface's ip address.
273                */
274               ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
275
276               if (ia0 == 0)
277                 {
278                   error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
279                   next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_DROP;
280                   pkts_no_interface_address++;
281                   goto do_trace;
282                 }
283
284               /* Add option 82 */
285               o->option = 82;   /* option 82 */
286               o->length = 12;   /* 12 octets to follow */
287               o->data[0] = 1;   /* suboption 1, circuit ID (=FIB id) */
288               o->data[1] = 4;   /* length of suboption */
289               u32 *o_ifid = (u32 *) & o->data[2];
290               *o_ifid = clib_host_to_net_u32 (original_sw_if_index);
291               o->data[6] = 5;   /* suboption 5 (client RX intfc address) */
292               o->data[7] = 4;   /* length 4 */
293               u32 *o_addr = (u32 *) & o->data[8];
294               *o_addr = ia0->as_u32;
295               o->data[12] = DHCP_PACKET_OPTION_END;
296
297               vss = dhcp_get_vss_info (dpm, fib_index, FIB_PROTOCOL_IP4);
298               if (vss)
299                 {
300                   u32 id_len;   /* length of VPN ID */
301
302                   if (vss->vss_type == VSS_TYPE_VPN_ID)
303                     {
304                       id_len = sizeof (vss->vpn_id);    /* vpn_id is 7 bytes */
305                       memcpy (&o->data[15], vss->vpn_id, id_len);
306                     }
307                   else if (vss->vss_type == VSS_TYPE_ASCII)
308                     {
309                       id_len = vec_len (vss->vpn_ascii_id);
310                       memcpy (&o->data[15], vss->vpn_ascii_id, id_len);
311                     }
312                   else          /* must be VSS_TYPE_DEFAULT, no VPN ID */
313                     id_len = 0;
314
315                   o->data[12] = 151;    /* vss suboption */
316                   o->data[13] = id_len + 1;     /* length: vss_type + id_len */
317                   o->data[14] = vss->vss_type;  /* vss option type */
318                   o->data[15 + id_len] = 152;   /* vss control suboption */
319                   o->data[16 + id_len] = 0;     /* length */
320                   o->data[17 + id_len] = DHCP_PACKET_OPTION_END;        /* "end-of-options" (0xFF) */
321                   /* 5 bytes for suboption headers 151+len, 152+len and 0xFF */
322                   o->length += id_len + 5;
323                 }
324
325               len = o->length + 3;
326               b0->current_length += len;
327               /* Fix IP header length and checksum */
328               old_l0 = ip0->length;
329               new_l0 = clib_net_to_host_u16 (old_l0);
330               new_l0 += len;
331               new_l0 = clib_host_to_net_u16 (new_l0);
332               ip0->length = new_l0;
333               sum0 = ip0->checksum;
334               sum0 = ip_csum_update (sum0, old_l0, new_l0, ip4_header_t,
335                                      length /* changed member */ );
336               ip0->checksum = ip_csum_fold (sum0);
337
338               /* Fix UDP length */
339               new_l0 = clib_net_to_host_u16 (u0->length);
340               new_l0 += len;
341               u0->length = clib_host_to_net_u16 (new_l0);
342             }
343           else
344             {
345               vlib_node_increment_counter
346                 (vm, dhcp_proxy_to_server_node.index,
347                  DHCP_PROXY_ERROR_OPTION_82_ERROR, 1);
348             }
349
350           next0 = DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP;
351
352           /*
353            * If we have multiple servers configured and this is the
354            * client's discover message, then send copies to each of
355            * those servers
356            */
357           if (is_discover && vec_len (proxy->dhcp_servers) > 1)
358             {
359               u32 ii;
360
361               for (ii = 1; ii < vec_len (proxy->dhcp_servers); ii++)
362                 {
363                   vlib_buffer_t *c0;
364                   u32 ci0;
365
366                   c0 = vlib_buffer_copy (vm, b0);
367                   if (c0 == NULL)
368                     {
369                       vlib_node_increment_counter
370                         (vm, dhcp_proxy_to_server_node.index,
371                          DHCP_PROXY_ERROR_ALLOC_FAIL, 1);
372                       continue;
373                     }
374                   VLIB_BUFFER_TRACE_TRAJECTORY_INIT (c0);
375                   ci0 = vlib_get_buffer_index (vm, c0);
376                   server = &proxy->dhcp_servers[ii];
377
378                   ip0 = vlib_buffer_get_current (c0);
379
380                   sum0 = ip0->checksum;
381                   old0 = ip0->dst_address.as_u32;
382                   new0 = server->dhcp_server.ip4.as_u32;
383                   ip0->dst_address.as_u32 = server->dhcp_server.ip4.as_u32;
384                   sum0 = ip_csum_update (sum0, old0, new0,
385                                          ip4_header_t /* structure */ ,
386                                          dst_address /* changed member */ );
387                   ip0->checksum = ip_csum_fold (sum0);
388
389                   to_next[0] = ci0;
390                   to_next += 1;
391                   n_left_to_next -= 1;
392
393                   vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
394                                                    to_next, n_left_to_next,
395                                                    ci0, next0);
396
397                   if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
398                     {
399                       dhcp_proxy_trace_t *tr;
400
401                       tr = vlib_add_trace (vm, node, c0, sizeof (*tr));
402                       tr->which = 0;    /* to server */
403                       tr->error = error0;
404                       tr->original_sw_if_index = original_sw_if_index;
405                       tr->sw_if_index = sw_if_index;
406                       if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
407                         tr->trace_ip4_address.as_u32 =
408                           server->dhcp_server.ip4.as_u32;
409
410                       clib_memcpy_fast (tr->packet_data, h0,
411                                         sizeof (tr->packet_data));
412
413                     }
414
415                   if (PREDICT_FALSE (0 == n_left_to_next))
416                     {
417                       vlib_put_next_frame (vm, node, next_index,
418                                            n_left_to_next);
419                       vlib_get_next_frame (vm, node, next_index,
420                                            to_next, n_left_to_next);
421                     }
422                 }
423             }
424         do_trace:
425           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
426             {
427               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
428                                                        b0, sizeof (*tr));
429               tr->which = 0;    /* to server */
430               tr->error = error0;
431               tr->original_sw_if_index = original_sw_if_index;
432               tr->sw_if_index = sw_if_index;
433               if (next0 == DHCP_PROXY_TO_SERVER_INPUT_NEXT_LOOKUP)
434                 tr->trace_ip4_address.as_u32 =
435                   proxy->dhcp_servers[0].dhcp_server.ip4.as_u32;
436               clib_memcpy_fast (tr->packet_data, h0,
437                                 sizeof (tr->packet_data));
438             }
439
440         do_enqueue:
441           to_next[0] = bi0;
442           to_next += 1;
443           n_left_to_next -= 1;
444
445           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
446                                            to_next, n_left_to_next,
447                                            bi0, next0);
448         }
449
450       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
451     }
452   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
453                                DHCP_PROXY_ERROR_RELAY_TO_CLIENT,
454                                pkts_to_client);
455   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
456                                DHCP_PROXY_ERROR_RELAY_TO_SERVER,
457                                pkts_to_server);
458   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
459                                DHCP_PROXY_ERROR_NO_SERVER, pkts_no_server);
460   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
461                                DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS,
462                                pkts_no_interface_address);
463   vlib_node_increment_counter (vm, dhcp_proxy_to_server_node.index,
464                                DHCP_PROXY_ERROR_PKT_TOO_BIG, pkts_too_big);
465   return from_frame->n_vectors;
466 }
467
468 /* *INDENT-OFF* */
469 VLIB_REGISTER_NODE (dhcp_proxy_to_server_node, static) = {
470   .function = dhcp_proxy_to_server_input,
471   .name = "dhcp-proxy-to-server",
472   /* Takes a vector of packets. */
473   .vector_size = sizeof (u32),
474
475   .n_errors = DHCP_PROXY_N_ERROR,
476   .error_strings = dhcp_proxy_error_strings,
477
478   .n_next_nodes = DHCP_PROXY_TO_SERVER_INPUT_N_NEXT,
479   .next_nodes = {
480 #define _(s,n) [DHCP_PROXY_TO_SERVER_INPUT_NEXT_##s] = n,
481     foreach_dhcp_proxy_to_server_input_next
482 #undef _
483   },
484
485   .format_buffer = format_dhcp_proxy_header_with_length,
486   .format_trace = format_dhcp_proxy_trace,
487 #if 0
488   .unformat_buffer = unformat_dhcp_proxy_header,
489 #endif
490 };
491 /* *INDENT-ON* */
492
493 typedef enum
494 {
495   DHCP4_PROXY_NEXT_DROP,
496   DHCP4_PROXY_NEXT_TX,
497   DHCP4_PROXY_N_NEXT,
498 } dhcp4_next_t;
499
500 static uword
501 dhcp_proxy_to_client_input (vlib_main_t * vm,
502                             vlib_node_runtime_t * node,
503                             vlib_frame_t * from_frame)
504 {
505   u32 n_left_from, *from, *to_next, n_left_to_next;
506   ethernet_main_t *em = vnet_get_ethernet_main ();
507   dhcp_proxy_main_t *dpm = &dhcp_proxy_main;
508   vnet_main_t *vnm = vnet_get_main ();
509   ip4_main_t *im = &ip4_main;
510   u32 next_index;
511
512   from = vlib_frame_vector_args (from_frame);
513   n_left_from = from_frame->n_vectors;
514   next_index = node->cached_next_index;
515
516   while (n_left_from > 0)
517     {
518       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
519
520       while (n_left_from > 0 && n_left_to_next > 0)
521         {
522           u32 bi0;
523           vlib_buffer_t *b0;
524           udp_header_t *u0;
525           dhcp_header_t *h0;
526           ip4_header_t *ip0 = 0;
527           ip4_address_t *ia0 = 0;
528           u32 old0, new0;
529           ip_csum_t sum0;
530           ethernet_interface_t *ei0;
531           ethernet_header_t *mac0;
532           vnet_hw_interface_t *hi0;
533           u32 sw_if_index = ~0;
534           vnet_sw_interface_t *si0;
535           u32 inner_vlan = (u32) ~ 0;
536           u32 outer_vlan = (u32) ~ 0;
537           u32 error0 = (u32) ~ 0;
538           vnet_sw_interface_t *swif;
539           u32 fib_index;
540           dhcp_proxy_t *proxy;
541           dhcp_server_t *server;
542           u32 original_sw_if_index = (u32) ~ 0;
543           dhcp4_next_t next0 = DHCP4_PROXY_NEXT_TX;
544           ip4_address_t relay_addr = {
545             .as_u32 = 0,
546           };
547
548           bi0 = to_next[0] = from[0];
549           from += 1;
550           to_next += 1;
551           n_left_from -= 1;
552           n_left_to_next -= 1;
553
554           b0 = vlib_get_buffer (vm, bi0);
555           h0 = vlib_buffer_get_current (b0);
556
557           /*
558            * udp_local hands us the DHCP header, need udp hdr,
559            * ip hdr to relay to client
560            */
561           vlib_buffer_advance (b0, -(sizeof (*u0)));
562           u0 = vlib_buffer_get_current (b0);
563
564           vlib_buffer_advance (b0, -(sizeof (*ip0)));
565           ip0 = vlib_buffer_get_current (b0);
566
567           /* Consumed by dhcp client code? */
568           if (dhcp_client_for_us (bi0, b0, ip0, u0, h0))
569             {
570               error0 = DHCP_PROXY_ERROR_FOR_US;
571               goto drop_packet;
572             }
573
574           // if (1 /* dpm->insert_option_82 */ )
575           /* linearize needed to "unclone" and scan options */
576           int rv = vlib_buffer_chain_linearize (vm, b0);
577           if ((b0->flags & VLIB_BUFFER_NEXT_PRESENT) != 0 || !rv)
578             {
579               error0 = DHCP_PROXY_ERROR_PKT_TOO_BIG;
580               goto drop_packet;
581             }
582
583           dhcp_option_t *o = h0->options, *end =
584             (void *) vlib_buffer_get_tail (b0);
585
586           /* Parse through TLVs looking for option 82.
587              The circuit-ID is the FIB number we need
588              to track down the client-facing interface */
589
590           while (o->option != DHCP_PACKET_OPTION_END && o < end)
591             {
592               if (o->option == 82)
593                 {
594                   u32 vss_exist = 0;
595                   u32 vss_ctrl = 0;
596                   dhcp_option_t *sub = (dhcp_option_t *) & o->data[0];
597                   dhcp_option_t *subend =
598                     (dhcp_option_t *) (o->data + o->length);
599                   while (sub->option != DHCP_PACKET_OPTION_END
600                          && sub < subend)
601                     {
602                       /* If this is one of ours, it will have
603                          total length 12, circuit-id suboption type,
604                          and the sw_if_index */
605                       if (sub->option == 1 && sub->length == 4)
606                         {
607                           sw_if_index = ((sub->data[0] << 24) |
608                                          (sub->data[1] << 16) |
609                                          (sub->data[2] << 8) |
610                                          (sub->data[3]));
611                         }
612                       else if (sub->option == 5 && sub->length == 4)
613                         {
614                           relay_addr.as_u8[0] = sub->data[0];
615                           relay_addr.as_u8[1] = sub->data[1];
616                           relay_addr.as_u8[2] = sub->data[2];
617                           relay_addr.as_u8[3] = sub->data[3];
618                         }
619                       else if (sub->option == 151 &&
620                                sub->length == 7 && sub->data[0] == 1)
621                         vss_exist = 1;
622                       else if (sub->option == 152 && sub->length == 0)
623                         vss_ctrl = 1;
624                       sub = (dhcp_option_t *) (sub->data + sub->length);
625                     }
626                   if (vss_ctrl && vss_exist)
627                     vlib_node_increment_counter
628                       (vm, dhcp_proxy_to_client_node.index,
629                        DHCP_PROXY_ERROR_OPTION_82_VSS_NOT_PROCESSED, 1);
630
631                 }
632               o = (dhcp_option_t *) (o->data + o->length);
633             }
634
635           if (sw_if_index == (u32) ~ 0)
636             {
637               error0 = DHCP_PROXY_ERROR_NO_OPTION_82;
638
639             drop_packet:
640               vlib_node_increment_counter (vm,
641                                            dhcp_proxy_to_client_node.index,
642                                            error0, 1);
643               b0->error = node->errors[error0];
644               next0 = DHCP4_PROXY_NEXT_DROP;
645               goto do_trace;
646             }
647
648           if (relay_addr.as_u32 == 0)
649             {
650               error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ADDR;
651               goto drop_packet;
652             }
653
654           if (sw_if_index >= vec_len (im->fib_index_by_sw_if_index))
655             {
656               error0 = DHCP_PROXY_ERROR_BAD_OPTION_82_ITF;
657               goto drop_packet;
658             }
659
660           fib_index = im->fib_index_by_sw_if_index[sw_if_index];
661           proxy = dhcp_get_proxy (dpm, fib_index, FIB_PROTOCOL_IP4);
662
663           if (PREDICT_FALSE (NULL == proxy))
664             {
665               error0 = DHCP_PROXY_ERROR_NO_SERVER;
666               goto drop_packet;
667             }
668
669           vec_foreach (server, proxy->dhcp_servers)
670           {
671             if (ip0->src_address.as_u32 == server->dhcp_server.ip4.as_u32)
672               {
673                 goto server_found;
674               }
675           }
676
677           error0 = DHCP_PROXY_ERROR_BAD_SVR_FIB_OR_ADDRESS;
678           goto drop_packet;
679
680         server_found:
681           vnet_buffer (b0)->sw_if_index[VLIB_TX] = sw_if_index;
682
683           swif = vnet_get_sw_interface (vnm, sw_if_index);
684           original_sw_if_index = sw_if_index;
685           if (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED)
686             sw_if_index = swif->unnumbered_sw_if_index;
687
688           ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
689           if (ia0 == 0)
690             {
691               error0 = DHCP_PROXY_ERROR_NO_INTERFACE_ADDRESS;
692               goto drop_packet;
693             }
694
695           if (relay_addr.as_u32 != ia0->as_u32)
696             {
697               error0 = DHCP_PROXY_ERROR_BAD_YIADDR;
698               goto drop_packet;
699             }
700
701           u0->checksum = 0;
702           u0->dst_port = clib_net_to_host_u16 (UDP_DST_PORT_dhcp_to_client);
703           sum0 = ip0->checksum;
704           old0 = ip0->dst_address.as_u32;
705           new0 = 0xFFFFFFFF;
706           ip0->dst_address.as_u32 = new0;
707           sum0 =
708             ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
709                             dst_address /* offset of changed member */ );
710           ip0->checksum = ip_csum_fold (sum0);
711
712           sum0 = ip0->checksum;
713           old0 = ip0->src_address.as_u32;
714           new0 = ia0->as_u32;
715           ip0->src_address.as_u32 = new0;
716           sum0 =
717             ip_csum_update (sum0, old0, new0, ip4_header_t /* structure */ ,
718                             src_address /* offset of changed member */ );
719           ip0->checksum = ip_csum_fold (sum0);
720
721           vlib_buffer_advance (b0, -(sizeof (ethernet_header_t)));
722           si0 = vnet_get_sw_interface (vnm, original_sw_if_index);
723           if (si0->type == VNET_SW_INTERFACE_TYPE_SUB)
724             {
725               if (si0->sub.eth.flags.one_tag == 1)
726                 {
727                   vlib_buffer_advance (b0, -4 /* space for 1 VLAN tag */ );
728                   outer_vlan = (si0->sub.eth.outer_vlan_id << 16) | 0x0800;
729                 }
730               else if (si0->sub.eth.flags.two_tags == 1)
731                 {
732                   vlib_buffer_advance (b0, -8 /* space for 2 VLAN tag */ );
733                   outer_vlan = (si0->sub.eth.outer_vlan_id << 16) | 0x8100;
734                   inner_vlan = (si0->sub.eth.inner_vlan_id << 16) | 0x0800;
735                 }
736             }
737
738           mac0 = vlib_buffer_get_current (b0);
739
740           hi0 = vnet_get_sup_hw_interface (vnm, original_sw_if_index);
741           ei0 = pool_elt_at_index (em->interfaces, hi0->hw_instance);
742           clib_memcpy (mac0->src_address, ei0->address,
743                        sizeof (ei0->address));
744           clib_memset (mac0->dst_address, 0xff, sizeof (mac0->dst_address));
745
746           if (si0->type == VNET_SW_INTERFACE_TYPE_SUB
747               && outer_vlan != (u32) ~ 0)
748             {
749               mac0->type = (si0->sub.eth.flags.dot1ad == 1) ?
750                 clib_net_to_host_u16 (0x88a8) : clib_net_to_host_u16 (0x8100);
751               u32 *vlan_tag = (u32 *) (mac0 + 1);
752               *vlan_tag = clib_host_to_net_u32 (outer_vlan);
753               if (inner_vlan != (u32) ~ 0)
754                 {
755                   u32 *inner_vlan_tag = (u32 *) (vlan_tag + 1);
756                   *inner_vlan_tag = clib_host_to_net_u32 (inner_vlan);
757                 }
758             }
759           else
760             {
761               mac0->type = clib_net_to_host_u16 (0x0800);
762             }
763
764         do_trace:
765           if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
766             {
767               dhcp_proxy_trace_t *tr = vlib_add_trace (vm, node,
768                                                        b0, sizeof (*tr));
769               tr->which = 1;    /* to client */
770               tr->trace_ip4_address.as_u32 = ia0 ? ia0->as_u32 : 0;
771               tr->error = error0;
772               tr->original_sw_if_index = original_sw_if_index;
773               tr->sw_if_index = sw_if_index;
774               clib_memcpy_fast (tr->packet_data, h0,
775                                 sizeof (tr->packet_data));
776             }
777
778           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
779                                            to_next, n_left_to_next,
780                                            bi0, next0);
781         }
782       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
783     }
784
785   return from_frame->n_vectors;
786 }
787
788 /* *INDENT-OFF* */
789 VLIB_REGISTER_NODE (dhcp_proxy_to_client_node, static) = {
790   .function = dhcp_proxy_to_client_input,
791   .name = "dhcp-proxy-to-client",
792   /* Takes a vector of packets. */
793   .vector_size = sizeof (u32),
794
795   .n_errors = DHCP_PROXY_N_ERROR,
796   .error_strings = dhcp_proxy_error_strings,
797   .format_buffer = format_dhcp_proxy_header_with_length,
798   .format_trace = format_dhcp_proxy_trace,
799 #if 0
800   .unformat_buffer = unformat_dhcp_proxy_header,
801 #endif
802   .n_next_nodes = DHCP4_PROXY_N_NEXT,
803   .next_nodes = {
804     [DHCP4_PROXY_NEXT_DROP] = "error-drop",
805     [DHCP4_PROXY_NEXT_TX] = "interface-output",
806   },
807 };
808 /* *INDENT-ON* */
809
810 void
811 dhcp_maybe_register_udp_ports (dhcp_port_reg_flags_t ports)
812 {
813   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
814   vlib_main_t *vm = dm->vlib_main;
815   int port_regs_diff = dm->udp_ports_registered ^ ports;
816
817   if (!port_regs_diff)
818     return;
819
820   if ((port_regs_diff & DHCP_PORT_REG_CLIENT) & ports)
821     udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_client,
822                            dhcp_proxy_to_client_node.index, 1 /* is_ip4 */ );
823
824   if ((port_regs_diff & DHCP_PORT_REG_SERVER) & ports)
825     udp_register_dst_port (vm, UDP_DST_PORT_dhcp_to_server,
826                            dhcp_proxy_to_server_node.index, 1 /* is_ip4 */ );
827
828   dm->udp_ports_registered |= ports;
829 }
830
831 static clib_error_t *
832 dhcp4_proxy_init (vlib_main_t * vm)
833 {
834   dhcp_proxy_main_t *dm = &dhcp_proxy_main;
835   vlib_node_t *error_drop_node;
836
837   error_drop_node = vlib_get_node_by_name (vm, (u8 *) "error-drop");
838   dm->error_drop_node_index = error_drop_node->index;
839   dm->vlib_main = vm;
840
841   return 0;
842 }
843
844
845 VLIB_INIT_FUNCTION (dhcp4_proxy_init);
846
847 int
848 dhcp4_proxy_set_server (ip46_address_t * addr,
849                         ip46_address_t * src_addr,
850                         u32 rx_table_id, u32 server_table_id, int is_del)
851 {
852   u32 rx_fib_index = 0;
853   int rc = 0;
854
855   const fib_prefix_t all_1s = {
856     .fp_len = 32,
857     .fp_addr.ip4.as_u32 = 0xffffffff,
858     .fp_proto = FIB_PROTOCOL_IP4,
859   };
860
861   if (ip46_address_is_zero (addr))
862     return VNET_API_ERROR_INVALID_DST_ADDRESS;
863
864   if (ip46_address_is_zero (src_addr))
865     return VNET_API_ERROR_INVALID_SRC_ADDRESS;
866
867   dhcp_maybe_register_udp_ports (DHCP_PORT_REG_CLIENT | DHCP_PORT_REG_SERVER);
868
869   rx_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
870                                                     rx_table_id,
871                                                     FIB_SOURCE_DHCP);
872
873   if (is_del)
874     {
875       if (dhcp_proxy_server_del (FIB_PROTOCOL_IP4, rx_fib_index,
876                                  addr, server_table_id))
877         {
878           fib_table_entry_special_remove (rx_fib_index,
879                                           &all_1s, FIB_SOURCE_DHCP);
880           fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
881         }
882     }
883   else
884     {
885       if (dhcp_proxy_server_add (FIB_PROTOCOL_IP4,
886                                  addr, src_addr,
887                                  rx_fib_index, server_table_id))
888         {
889           fib_table_entry_special_add (rx_fib_index,
890                                        &all_1s,
891                                        FIB_SOURCE_DHCP, FIB_ENTRY_FLAG_LOCAL);
892           fib_table_lock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
893         }
894     }
895   fib_table_unlock (rx_fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_DHCP);
896
897   return (rc);
898 }
899
900 static clib_error_t *
901 dhcp4_proxy_set_command_fn (vlib_main_t * vm,
902                             unformat_input_t * input,
903                             vlib_cli_command_t * cmd)
904 {
905   ip46_address_t server_addr, src_addr;
906   u32 server_table_id = 0, rx_table_id = 0;
907   int is_del = 0;
908   int set_src = 0, set_server = 0;
909
910   clib_memset (&server_addr, 0, sizeof (server_addr));
911   clib_memset (&src_addr, 0, sizeof (src_addr));
912
913   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
914     {
915       if (unformat (input, "server %U",
916                     unformat_ip4_address, &server_addr.ip4))
917         set_server = 1;
918       else if (unformat (input, "server-fib-id %d", &server_table_id))
919         ;
920       else if (unformat (input, "rx-fib-id %d", &rx_table_id))
921         ;
922       else if (unformat (input, "src-address %U",
923                          unformat_ip4_address, &src_addr.ip4))
924         set_src = 1;
925       else if (unformat (input, "delete") || unformat (input, "del"))
926         is_del = 1;
927       else
928         break;
929     }
930
931   if (is_del || (set_server && set_src))
932     {
933       int rv;
934
935       rv = dhcp4_proxy_set_server (&server_addr, &src_addr, rx_table_id,
936                                    server_table_id, is_del);
937       switch (rv)
938         {
939         case 0:
940           return 0;
941
942         case VNET_API_ERROR_INVALID_DST_ADDRESS:
943           return clib_error_return (0, "Invalid server address");
944
945         case VNET_API_ERROR_INVALID_SRC_ADDRESS:
946           return clib_error_return (0, "Invalid src address");
947
948         case VNET_API_ERROR_NO_SUCH_ENTRY:
949           return clib_error_return
950             (0, "Fib id %d: no per-fib DHCP server configured", rx_table_id);
951
952         default:
953           return clib_error_return (0, "BUG: rv %d", rv);
954         }
955     }
956   else
957     return clib_error_return (0, "parse error`%U'",
958                               format_unformat_error, input);
959 }
960
961 /* *INDENT-OFF* */
962 VLIB_CLI_COMMAND (dhcp_proxy_set_command, static) = {
963   .path = "set dhcp proxy",
964   .short_help = "set dhcp proxy [del] server <ip-addr> src-address <ip-addr> [server-fib-id <n>] [rx-fib-id <n>]",
965   .function = dhcp4_proxy_set_command_fn,
966 };
967 /* *INDENT-ON* */
968
969 static u8 *
970 format_dhcp4_proxy_server (u8 * s, va_list * args)
971 {
972   dhcp_proxy_t *proxy = va_arg (*args, dhcp_proxy_t *);
973   ip4_fib_t *rx_fib, *server_fib;
974   dhcp_server_t *server;
975
976   if (proxy == 0)
977     {
978       s = format (s, "%=14s%=16s%s", "RX FIB", "Src Address",
979                   "Servers FIB,Address");
980       return s;
981     }
982
983   rx_fib = ip4_fib_get (proxy->rx_fib_index);
984
985   s = format (s, "%=14u%=16U",
986               rx_fib->table_id,
987               format_ip46_address, &proxy->dhcp_src_address, IP46_TYPE_ANY);
988
989   vec_foreach (server, proxy->dhcp_servers)
990   {
991     server_fib = ip4_fib_get (server->server_fib_index);
992     s = format (s, "%u,%U  ",
993                 server_fib->table_id,
994                 format_ip46_address, &server->dhcp_server, IP46_TYPE_ANY);
995   }
996   return s;
997 }
998
999 static int
1000 dhcp4_proxy_show_walk (dhcp_proxy_t * server, void *ctx)
1001 {
1002   vlib_main_t *vm = ctx;
1003
1004   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server, server);
1005
1006   return (1);
1007 }
1008
1009 static clib_error_t *
1010 dhcp4_proxy_show_command_fn (vlib_main_t * vm,
1011                              unformat_input_t * input,
1012                              vlib_cli_command_t * cmd)
1013 {
1014   vlib_cli_output (vm, "%U", format_dhcp4_proxy_server,
1015                    NULL /* header line */ );
1016
1017   dhcp_proxy_walk (FIB_PROTOCOL_IP4, dhcp4_proxy_show_walk, vm);
1018
1019   return (NULL);
1020 }
1021
1022 /* *INDENT-OFF* */
1023 VLIB_CLI_COMMAND (dhcp_proxy_show_command, static) = {
1024   .path = "show dhcp proxy",
1025   .short_help = "Display dhcp proxy server info",
1026   .function = dhcp4_proxy_show_command_fn,
1027 };
1028 /* *INDENT-ON* */
1029
1030 static clib_error_t *
1031 dhcp_option_82_vss_fn (vlib_main_t * vm,
1032                        unformat_input_t * input, vlib_cli_command_t * cmd)
1033 {
1034   u8 is_del = 0, vss_type = VSS_TYPE_DEFAULT;
1035   u32 oui = 0, fib_id = 0, tbl_id = ~0;
1036   u8 *vpn_ascii_id = 0;
1037
1038   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
1039     {
1040       if (unformat (input, "table %d", &tbl_id))
1041         ;
1042       else if (unformat (input, "oui %d", &oui))
1043         vss_type = VSS_TYPE_VPN_ID;
1044       else if (unformat (input, "vpn-id %d", &fib_id))
1045         vss_type = VSS_TYPE_VPN_ID;
1046       else if (unformat (input, "vpn-ascii-id %s", &vpn_ascii_id))
1047         vss_type = VSS_TYPE_ASCII;
1048       else if (unformat (input, "delete") || unformat (input, "del"))
1049         is_del = 1;
1050       else
1051         break;
1052     }
1053
1054   if (tbl_id == ~0)
1055     return clib_error_return (0, "no table ID specified.");
1056
1057   int rv = dhcp_proxy_set_vss (FIB_PROTOCOL_IP4, tbl_id, vss_type,
1058                                vpn_ascii_id, oui, fib_id, is_del);
1059   switch (rv)
1060     {
1061     case 0:
1062       return 0;
1063     case VNET_API_ERROR_NO_SUCH_ENTRY:
1064       return clib_error_return (0,
1065                                 "option 82 vss for table %d not found in in pool.",
1066                                 tbl_id);
1067     default:
1068       return clib_error_return (0, "BUG: rv %d", rv);
1069
1070     }
1071 }
1072
1073 /* *INDENT-OFF* */
1074 VLIB_CLI_COMMAND (dhcp_proxy_vss_command,static) = {
1075   .path = "set dhcp option-82 vss",
1076   .short_help = "set dhcp option-82 vss [del] table <table id> [oui <n> vpn-id <n> | vpn-ascii-id <text>]",
1077   .function = dhcp_option_82_vss_fn,
1078 };
1079 /* *INDENT-ON* */
1080
1081 static clib_error_t *
1082 dhcp_vss_show_command_fn (vlib_main_t * vm,
1083                           unformat_input_t * input, vlib_cli_command_t * cmd)
1084 {
1085   dhcp_vss_walk (FIB_PROTOCOL_IP4, dhcp_vss_show_walk, vm);
1086
1087   return (NULL);
1088 }
1089
1090 /* *INDENT-OFF* */
1091 VLIB_CLI_COMMAND (dhcp_proxy_vss_show_command, static) = {
1092   .path = "show dhcp vss",
1093   .short_help = "show dhcp VSS",
1094   .function = dhcp_vss_show_command_fn,
1095 };
1096 /* *INDENT-ON* */
1097
1098 static clib_error_t *
1099 dhcp_option_82_address_show_command_fn (vlib_main_t * vm,
1100                                         unformat_input_t * input,
1101                                         vlib_cli_command_t * cmd)
1102 {
1103   vnet_main_t *vnm = vnet_get_main ();
1104   u32 sw_if_index0 = 0, sw_if_index;
1105   vnet_sw_interface_t *swif;
1106   ip4_address_t *ia0;
1107
1108   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
1109     {
1110
1111       if (unformat (input, "%U",
1112                     unformat_vnet_sw_interface, vnm, &sw_if_index0))
1113         {
1114           swif = vnet_get_sw_interface (vnm, sw_if_index0);
1115           sw_if_index = (swif->flags & VNET_SW_INTERFACE_FLAG_UNNUMBERED) ?
1116             swif->unnumbered_sw_if_index : sw_if_index0;
1117           ia0 = ip4_interface_first_address (&ip4_main, sw_if_index, 0);
1118           if (ia0)
1119             {
1120               vlib_cli_output (vm, "%=20s%=20s", "interface",
1121                                "source IP address");
1122
1123               vlib_cli_output (vm, "%=20U%=20U",
1124                                format_vnet_sw_if_index_name,
1125                                vnm, sw_if_index0, format_ip4_address, ia0);
1126             }
1127           else
1128             vlib_cli_output (vm, "%=34s %=20U",
1129                              "No IPv4 address configured on",
1130                              format_vnet_sw_if_index_name, vnm, sw_if_index);
1131         }
1132       else
1133         break;
1134     }
1135
1136   return 0;
1137 }
1138
1139 /* *INDENT-OFF* */
1140 VLIB_CLI_COMMAND (dhcp_proxy_address_show_command,static) = {
1141   .path = "show dhcp option-82-address interface",
1142   .short_help = "show dhcp option-82-address interface <interface>",
1143   .function = dhcp_option_82_address_show_command_fn,
1144 };
1145 /* *INDENT-ON* */
1146
1147 /*
1148  * fd.io coding-style-patch-verification: ON
1149  *
1150  * Local Variables:
1151  * eval: (c-set-style "gnu")
1152  * End:
1153  */