2 * Copyright (c) 2015 Cisco and/or its affiliates.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at:
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
16 * ip/icmp4.c: ipv4 icmp
18 * Copyright (c) 2008 Eliot Dresselhaus
20 * Permission is hereby granted, free of charge, to any person obtaining
21 * a copy of this software and associated documentation files (the
22 * "Software"), to deal in the Software without restriction, including
23 * without limitation the rights to use, copy, modify, merge, publish,
24 * distribute, sublicense, and/or sell copies of the Software, and to
25 * permit persons to whom the Software is furnished to do so, subject to
26 * the following conditions:
28 * The above copyright notice and this permission notice shall be
29 * included in all copies or substantial portions of the Software.
31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
32 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
33 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
34 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
35 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
36 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
37 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
40 #include <vlib/vlib.h>
41 #include <vnet/ip/ip.h>
42 #include <vnet/pg/pg.h>
45 static char * icmp_error_strings[] = {
51 static u8 * format_ip4_icmp_type_and_code (u8 * s, va_list * args)
53 icmp4_type_t type = va_arg (*args, int);
54 u8 code = va_arg (*args, int);
57 #define _(n,f) case n: t = #f; break;
70 return format (s, "unknown 0x%x", type);
72 s = format (s, "%s", t);
75 switch ((type << 8) | code)
77 #define _(a,n,f) case (ICMP4_##a << 8) | (n): t = #f; break;
85 s = format (s, " %s", t);
90 static u8 * format_ip4_icmp_header (u8 * s, va_list * args)
92 icmp46_header_t * icmp = va_arg (*args, icmp46_header_t *);
93 u32 max_header_bytes = va_arg (*args, u32);
96 if (max_header_bytes < sizeof (icmp[0]))
97 return format (s, "ICMP header truncated");
99 s = format (s, "ICMP %U checksum 0x%x",
100 format_ip4_icmp_type_and_code, icmp->type, icmp->code,
101 clib_net_to_host_u16 (icmp->checksum));
106 static u8 * format_icmp_input_trace (u8 * s, va_list * va)
108 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
109 CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
110 icmp_input_trace_t * t = va_arg (*va, icmp_input_trace_t *);
114 t->packet_data, sizeof (t->packet_data));
120 ICMP_INPUT_NEXT_ERROR,
125 uword * type_and_code_by_name;
127 uword * type_by_name;
129 /* Vector dispatch table indexed by [icmp type]. */
130 u8 ip4_input_next_index_by_type[256];
133 icmp4_main_t icmp4_main;
136 ip4_icmp_input (vlib_main_t * vm,
137 vlib_node_runtime_t * node,
138 vlib_frame_t * frame)
140 icmp4_main_t * im = &icmp4_main;
141 uword n_packets = frame->n_vectors;
142 u32 * from, * to_next;
143 u32 n_left_from, n_left_to_next, next;
145 from = vlib_frame_vector_args (frame);
146 n_left_from = n_packets;
147 next = node->cached_next_index;
149 if (node->flags & VLIB_NODE_FLAG_TRACE)
150 vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
152 sizeof (icmp_input_trace_t));
154 while (n_left_from > 0)
156 vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
158 while (n_left_from > 0 && n_left_to_next > 0)
162 icmp46_header_t * icmp0;
166 if (PREDICT_TRUE (n_left_from > 2))
168 vlib_prefetch_buffer_with_index (vm, from[2], LOAD);
169 p0 = vlib_get_buffer (vm, from[1]);
170 ip0 = vlib_buffer_get_current (p0);
171 CLIB_PREFETCH(ip0, CLIB_CACHE_LINE_BYTES, LOAD);
174 bi0 = to_next[0] = from[0];
181 p0 = vlib_get_buffer (vm, bi0);
182 ip0 = vlib_buffer_get_current (p0);
183 icmp0 = ip4_next_header (ip0);
185 next0 = im->ip4_input_next_index_by_type[type0];
187 p0->error = node->errors[ICMP4_ERROR_UNKNOWN_TYPE];
188 if (PREDICT_FALSE (next0 != next))
190 vlib_put_next_frame (vm, node, next, n_left_to_next + 1);
192 vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
199 vlib_put_next_frame (vm, node, next, n_left_to_next);
202 return frame->n_vectors;
205 VLIB_REGISTER_NODE (ip4_icmp_input_node,static) = {
206 .function = ip4_icmp_input,
207 .name = "ip4-icmp-input",
209 .vector_size = sizeof (u32),
211 .format_trace = format_icmp_input_trace,
213 .n_errors = ARRAY_LEN (icmp_error_strings),
214 .error_strings = icmp_error_strings,
218 [ICMP_INPUT_NEXT_ERROR] = "error-punt",
223 ip4_icmp_echo_request (vlib_main_t * vm,
224 vlib_node_runtime_t * node,
225 vlib_frame_t * frame)
227 uword n_packets = frame->n_vectors;
228 u32 * from, * to_next;
229 u32 n_left_from, n_left_to_next, next;
230 ip4_main_t * i4m = &ip4_main;
231 u16 * fragment_ids, * fid;
232 u8 host_config_ttl = i4m->host_config.ttl;
234 from = vlib_frame_vector_args (frame);
235 n_left_from = n_packets;
236 next = node->cached_next_index;
238 if (node->flags & VLIB_NODE_FLAG_TRACE)
239 vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
241 sizeof (icmp_input_trace_t));
243 /* Get random fragment IDs for replies. */
244 fid = fragment_ids = clib_random_buffer_get_data (&vm->random_buffer,
245 n_packets * sizeof (fragment_ids[0]));
247 while (n_left_from > 0)
249 vlib_get_next_frame (vm, node, next, to_next, n_left_to_next);
251 while (n_left_from > 2 && n_left_to_next > 2)
253 vlib_buffer_t * p0, * p1;
254 ip4_header_t * ip0, * ip1;
255 icmp46_header_t * icmp0, * icmp1;
258 ip_csum_t sum0, sum1;
260 bi0 = to_next[0] = from[0];
261 bi1 = to_next[1] = from[1];
268 p0 = vlib_get_buffer (vm, bi0);
269 p1 = vlib_get_buffer (vm, bi1);
270 ip0 = vlib_buffer_get_current (p0);
271 ip1 = vlib_buffer_get_current (p1);
272 icmp0 = ip4_next_header (ip0);
273 icmp1 = ip4_next_header (ip1);
275 vnet_buffer (p0)->sw_if_index[VLIB_RX] = vnet_main.local_interface_sw_if_index;
276 vnet_buffer (p1)->sw_if_index[VLIB_RX] = vnet_main.local_interface_sw_if_index;
278 /* Update ICMP checksum. */
279 sum0 = icmp0->checksum;
280 sum1 = icmp1->checksum;
282 ASSERT (icmp0->type == ICMP4_echo_request);
283 ASSERT (icmp1->type == ICMP4_echo_request);
284 sum0 = ip_csum_update (sum0, ICMP4_echo_request, ICMP4_echo_reply,
285 icmp46_header_t, type);
286 sum1 = ip_csum_update (sum1, ICMP4_echo_request, ICMP4_echo_reply,
287 icmp46_header_t, type);
288 icmp0->type = ICMP4_echo_reply;
289 icmp1->type = ICMP4_echo_reply;
291 icmp0->checksum = ip_csum_fold (sum0);
292 icmp1->checksum = ip_csum_fold (sum1);
294 src0 = ip0->src_address.data_u32;
295 src1 = ip1->src_address.data_u32;
296 dst0 = ip0->dst_address.data_u32;
297 dst1 = ip1->dst_address.data_u32;
299 /* Swap source and destination address.
300 Does not change checksum. */
301 ip0->src_address.data_u32 = dst0;
302 ip1->src_address.data_u32 = dst1;
303 ip0->dst_address.data_u32 = src0;
304 ip1->dst_address.data_u32 = src1;
306 /* Update IP checksum. */
307 sum0 = ip0->checksum;
308 sum1 = ip1->checksum;
310 sum0 = ip_csum_update (sum0, ip0->ttl, host_config_ttl,
312 sum1 = ip_csum_update (sum1, ip1->ttl, host_config_ttl,
314 ip0->ttl = host_config_ttl;
315 ip1->ttl = host_config_ttl;
317 /* New fragment id. */
318 sum0 = ip_csum_update (sum0, ip0->fragment_id, fid[0],
319 ip4_header_t, fragment_id);
320 sum1 = ip_csum_update (sum1, ip1->fragment_id, fid[1],
321 ip4_header_t, fragment_id);
322 ip0->fragment_id = fid[0];
323 ip1->fragment_id = fid[1];
326 ip0->checksum = ip_csum_fold (sum0);
327 ip1->checksum = ip_csum_fold (sum1);
329 ASSERT (ip0->checksum == ip4_header_checksum (ip0));
330 ASSERT (ip1->checksum == ip4_header_checksum (ip1));
333 while (n_left_from > 0 && n_left_to_next > 0)
337 icmp46_header_t * icmp0;
341 bi0 = to_next[0] = from[0];
348 p0 = vlib_get_buffer (vm, bi0);
349 ip0 = vlib_buffer_get_current (p0);
350 icmp0 = ip4_next_header (ip0);
352 vnet_buffer (p0)->sw_if_index[VLIB_RX] = vnet_main.local_interface_sw_if_index;
354 /* Update ICMP checksum. */
355 sum0 = icmp0->checksum;
357 ASSERT (icmp0->type == ICMP4_echo_request);
358 sum0 = ip_csum_update (sum0, ICMP4_echo_request, ICMP4_echo_reply,
359 icmp46_header_t, type);
360 icmp0->type = ICMP4_echo_reply;
361 icmp0->checksum = ip_csum_fold (sum0);
363 src0 = ip0->src_address.data_u32;
364 dst0 = ip0->dst_address.data_u32;
365 ip0->src_address.data_u32 = dst0;
366 ip0->dst_address.data_u32 = src0;
368 /* Update IP checksum. */
369 sum0 = ip0->checksum;
371 sum0 = ip_csum_update (sum0, ip0->ttl, host_config_ttl,
373 ip0->ttl = host_config_ttl;
375 sum0 = ip_csum_update (sum0, ip0->fragment_id, fid[0],
376 ip4_header_t, fragment_id);
377 ip0->fragment_id = fid[0];
380 ip0->checksum = ip_csum_fold (sum0);
382 ASSERT (ip0->checksum == ip4_header_checksum (ip0));
385 vlib_put_next_frame (vm, node, next, n_left_to_next);
388 vlib_error_count (vm, ip4_icmp_input_node.index,
389 ICMP4_ERROR_ECHO_REPLIES_SENT,
392 return frame->n_vectors;
395 VLIB_REGISTER_NODE (ip4_icmp_echo_request_node,static) = {
396 .function = ip4_icmp_echo_request,
397 .name = "ip4-icmp-echo-request",
399 .vector_size = sizeof (u32),
401 .format_trace = format_icmp_input_trace,
405 [0] = "ip4-rewrite-local",
410 IP4_ICMP_ERROR_NEXT_DROP,
411 IP4_ICMP_ERROR_NEXT_LOOKUP,
412 IP4_ICMP_ERROR_N_NEXT,
413 } ip4_icmp_error_next_t;
416 icmp4_error_set_vnet_buffer (vlib_buffer_t *b, u8 type, u8 code, u32 data)
418 vnet_buffer(b)->ip.icmp.type = type;
419 vnet_buffer(b)->ip.icmp.code = code;
420 vnet_buffer(b)->ip.icmp.data = data;
424 icmp4_icmp_type_to_error (u8 type)
427 case ICMP4_destination_unreachable:
428 return ICMP4_ERROR_DEST_UNREACH_SENT;
429 case ICMP4_time_exceeded:
430 return ICMP4_ERROR_TTL_EXPIRE_SENT;
431 case ICMP4_parameter_problem:
432 return ICMP4_ERROR_PARAM_PROBLEM_SENT;
434 return ICMP4_ERROR_DROP;
439 ip4_icmp_error (vlib_main_t * vm,
440 vlib_node_runtime_t * node,
441 vlib_frame_t * frame)
443 u32 * from, * to_next;
444 uword n_left_from, n_left_to_next;
445 ip4_icmp_error_next_t next_index;
446 ip4_main_t *im = &ip4_main;
447 ip_lookup_main_t * lm = &im->lookup_main;
449 from = vlib_frame_vector_args(frame);
450 n_left_from = frame->n_vectors;
451 next_index = node->cached_next_index;
453 if (node->flags & VLIB_NODE_FLAG_TRACE)
454 vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
455 /* stride */ 1, sizeof (icmp_input_trace_t));
457 while (n_left_from > 0) {
458 vlib_get_next_frame(vm, node, next_index, to_next, n_left_to_next);
460 while (n_left_from > 0 && n_left_to_next > 0) {
462 u32 next0 = IP4_ICMP_ERROR_NEXT_LOOKUP;
463 u8 error0 = ICMP4_ERROR_NONE;
465 ip4_header_t * ip0, * out_ip0;
466 icmp46_header_t * icmp0;
467 u32 sw_if_index0, if_add_index0;
470 /* Speculatively enqueue p0 to the current next frame */
477 p0 = vlib_get_buffer(vm, pi0);
478 ip0 = vlib_buffer_get_current(p0);
479 sw_if_index0 = vnet_buffer(p0)->sw_if_index[VLIB_RX];
482 * RFC1812 says to keep as much of the original packet as
483 * possible within the minimum MTU (576). We cheat "a little"
484 * here by keeping whatever fits in the first buffer, to be more
487 if (PREDICT_FALSE(p0->total_length_not_including_first_buffer)) {
488 /* clear current_length of all other buffers in chain */
489 vlib_buffer_t *b = p0;
490 p0->total_length_not_including_first_buffer = 0;
491 while (b->flags & VLIB_BUFFER_NEXT_PRESENT) {
492 b = vlib_get_buffer (vm, b->next_buffer);
493 b->current_length = 0;
496 p0->current_length = p0->current_length > 576 ? 576 : p0->current_length;
498 /* Add IP header and ICMPv4 header including a 4 byte data field */
499 vlib_buffer_advance(p0,
500 -sizeof(ip4_header_t)-sizeof(icmp46_header_t)-4);
501 out_ip0 = vlib_buffer_get_current(p0);
502 icmp0 = (icmp46_header_t *) &out_ip0[1];
504 /* Fill ip header fields */
505 out_ip0->ip_version_and_header_length = 0x45;
507 out_ip0->length = clib_host_to_net_u16(p0->current_length);
508 out_ip0->fragment_id = 0;
509 out_ip0->flags_and_fragment_offset = 0;
511 out_ip0->protocol = IP_PROTOCOL_ICMP;
512 out_ip0->dst_address = ip0->src_address;
514 lm->if_address_pool_index_by_sw_if_index[sw_if_index0];
515 if (PREDICT_TRUE(if_add_index0 != ~0)) {
516 ip_interface_address_t *if_add =
517 pool_elt_at_index(lm->if_address_pool, if_add_index0);
518 ip4_address_t *if_ip =
519 ip_interface_address_get_address(lm, if_add);
520 out_ip0->src_address = *if_ip;
522 /* interface has no IP4 address - should not happen */
523 next0 = IP4_ICMP_ERROR_NEXT_DROP;
524 error0 = ICMP4_ERROR_DROP;
526 out_ip0->checksum = ip4_header_checksum(out_ip0);
528 /* Fill icmp header fields */
529 icmp0->type = vnet_buffer(p0)->ip.icmp.type;
530 icmp0->code = vnet_buffer(p0)->ip.icmp.code;
531 *((u32 *)(icmp0 + 1)) = clib_host_to_net_u32(vnet_buffer(p0)->ip.icmp.data);
533 sum = ip_incremental_checksum(0, icmp0, p0->current_length - sizeof(ip4_header_t));
534 icmp0->checksum = ~ip_csum_fold(sum);
536 /* Update error status */
537 if (error0 == ICMP4_ERROR_NONE)
538 error0 = icmp4_icmp_type_to_error(icmp0->type);
539 vlib_error_count(vm, node->node_index, error0, 1);
541 /* Verify speculative enqueue, maybe switch current next frame */
542 vlib_validate_buffer_enqueue_x1(vm, node, next_index,
543 to_next, n_left_to_next,
546 vlib_put_next_frame(vm, node, next_index, n_left_to_next);
549 return frame->n_vectors;
552 VLIB_REGISTER_NODE (ip4_icmp_error_node) = {
553 .function = ip4_icmp_error,
554 .name = "ip4-icmp-error",
555 .vector_size = sizeof (u32),
557 .n_errors = ARRAY_LEN (icmp_error_strings),
558 .error_strings = icmp_error_strings,
560 .n_next_nodes = IP4_ICMP_ERROR_N_NEXT,
562 [IP4_ICMP_ERROR_NEXT_DROP] = "error-drop",
563 [IP4_ICMP_ERROR_NEXT_LOOKUP] = "ip4-lookup",
566 .format_trace = format_icmp_input_trace,
570 static uword unformat_icmp_type_and_code (unformat_input_t * input, va_list * args)
572 icmp46_header_t * h = va_arg (*args, icmp46_header_t *);
573 icmp4_main_t * cm = &icmp4_main;
576 if (unformat_user (input, unformat_vlib_number_by_name,
577 cm->type_and_code_by_name, &i))
579 h->type = (i >> 8) & 0xff;
580 h->code = (i >> 0) & 0xff;
582 else if (unformat_user (input, unformat_vlib_number_by_name,
583 cm->type_by_name, &i))
595 icmp4_pg_edit_function (pg_main_t * pg,
601 vlib_main_t * vm = pg->vlib_main;
602 u32 ip_offset, icmp_offset;
604 icmp_offset = g->start_byte_offset;
605 ip_offset = (g-1)->start_byte_offset;
607 while (n_packets >= 1)
611 icmp46_header_t * icmp0;
614 p0 = vlib_get_buffer (vm, packets[0]);
618 ASSERT (p0->current_data == 0);
619 ip0 = (void *) (p0->data + ip_offset);
620 icmp0 = (void *) (p0->data + icmp_offset);
621 len0 = clib_net_to_host_u16 (ip0->length) - ip4_header_bytes (ip0);
622 icmp0->checksum = ~ ip_csum_fold (ip_incremental_checksum (0, icmp0, len0));
627 pg_edit_t type, code;
629 } pg_icmp46_header_t;
632 pg_icmp_header_init (pg_icmp46_header_t * p)
634 /* Initialize fields that are not bit fields in the IP header. */
635 #define _(f) pg_edit_init (&p->f, icmp46_header_t, f);
643 unformat_pg_icmp_header (unformat_input_t * input, va_list * args)
645 pg_stream_t * s = va_arg (*args, pg_stream_t *);
646 pg_icmp46_header_t * p;
649 p = pg_create_edit_group (s, sizeof (p[0]), sizeof (icmp46_header_t),
651 pg_icmp_header_init (p);
653 p->checksum.type = PG_EDIT_UNSPECIFIED;
658 if (! unformat (input, "ICMP %U", unformat_icmp_type_and_code, &tmp))
661 pg_edit_set_fixed (&p->type, tmp.type);
662 pg_edit_set_fixed (&p->code, tmp.code);
668 if (unformat (input, "checksum %U",
670 unformat_pg_number, &p->checksum))
673 /* Can't parse input: try next protocol level. */
678 if (! unformat_user (input, unformat_pg_payload, s))
681 if (p->checksum.type == PG_EDIT_UNSPECIFIED)
683 pg_edit_group_t * g = pg_stream_get_group (s, group_index);
684 g->edit_function = icmp4_pg_edit_function;
685 g->edit_function_opaque = 0;
691 /* Free up any edits we may have added. */
692 pg_free_edit_group (s);
696 void ip4_icmp_register_type (vlib_main_t * vm, icmp4_type_t type,
699 icmp4_main_t * im = &icmp4_main;
701 ASSERT ((int)type < ARRAY_LEN (im->ip4_input_next_index_by_type));
702 im->ip4_input_next_index_by_type[type]
703 = vlib_node_add_next (vm, ip4_icmp_input_node.index, node_index);
706 static clib_error_t *
707 icmp4_init (vlib_main_t * vm)
709 ip_main_t * im = &ip_main;
710 ip_protocol_info_t * pi;
711 icmp4_main_t * cm = &icmp4_main;
712 clib_error_t * error;
714 error = vlib_call_init_function (vm, ip_main_init);
719 pi = ip_get_protocol_info (im, IP_PROTOCOL_ICMP);
720 pi->format_header = format_ip4_icmp_header;
721 pi->unformat_pg_edit = unformat_pg_icmp_header;
723 cm->type_by_name = hash_create_string (0, sizeof (uword));
724 #define _(n,t) hash_set_mem (cm->type_by_name, #t, (n));
728 cm->type_and_code_by_name = hash_create_string (0, sizeof (uword));
729 #define _(a,n,t) hash_set_mem (cm->type_by_name, #t, (n) | (ICMP4_##a << 8));
733 memset (cm->ip4_input_next_index_by_type,
734 ICMP_INPUT_NEXT_ERROR,
735 sizeof (cm->ip4_input_next_index_by_type));
737 ip4_icmp_register_type (vm, ICMP4_echo_request, ip4_icmp_echo_request_node.index);
742 VLIB_INIT_FUNCTION (icmp4_init);