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/ip4_input.c: IP v4 input node
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 <vnet/ip/ip.h>
41 #include <vnet/ethernet/ethernet.h>
42 #include <vnet/ppp/ppp.h>
43 #include <vnet/hdlc/hdlc.h>
51 format_ip4_input_trace (u8 * s, va_list * va)
53 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*va, vlib_main_t *);
54 CLIB_UNUSED (vlib_node_t * node) = va_arg (*va, vlib_node_t *);
55 ip4_input_trace_t *t = va_arg (*va, ip4_input_trace_t *);
58 format_ip4_header, t->packet_data, sizeof (t->packet_data));
67 IP4_INPUT_NEXT_LOOKUP,
68 IP4_INPUT_NEXT_LOOKUP_MULTICAST,
69 IP4_INPUT_NEXT_ICMP_ERROR,
73 /* Validate IP v4 packets and pass them either to forwarding code
74 or drop/punt exception packets. */
76 ip4_input_inline (vlib_main_t * vm,
77 vlib_node_runtime_t * node,
78 vlib_frame_t * frame, int verify_checksum)
80 ip4_main_t *im = &ip4_main;
81 vnet_main_t *vnm = vnet_get_main ();
82 ip_lookup_main_t *lm = &im->lookup_main;
83 u32 n_left_from, *from, *to_next;
84 ip4_input_next_t next_index;
85 vlib_node_runtime_t *error_node =
86 vlib_node_get_runtime (vm, ip4_input_node.index);
87 vlib_simple_counter_main_t *cm;
88 u32 cpu_index = os_get_cpu_number ();
90 from = vlib_frame_vector_args (frame);
91 n_left_from = frame->n_vectors;
92 next_index = node->cached_next_index;
94 if (node->flags & VLIB_NODE_FLAG_TRACE)
95 vlib_trace_frame_buffers_only (vm, node, from, frame->n_vectors,
97 sizeof (ip4_input_trace_t));
99 cm = vec_elt_at_index (vnm->interface_main.sw_if_counters,
100 VNET_INTERFACE_COUNTER_IP4);
102 while (n_left_from > 0)
106 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
108 while (n_left_from >= 4 && n_left_to_next >= 2)
110 vlib_buffer_t *p0, *p1;
111 ip4_header_t *ip0, *ip1;
112 u32 sw_if_index0, pi0, ip_len0, cur_len0, next0;
113 u32 sw_if_index1, pi1, ip_len1, cur_len1, next1;
114 i32 len_diff0, len_diff1;
115 u8 error0, error1, arc0, arc1;
117 /* Prefetch next iteration. */
119 vlib_buffer_t *p2, *p3;
121 p2 = vlib_get_buffer (vm, from[2]);
122 p3 = vlib_get_buffer (vm, from[3]);
124 vlib_prefetch_buffer_header (p2, LOAD);
125 vlib_prefetch_buffer_header (p3, LOAD);
127 CLIB_PREFETCH (p2->data, sizeof (ip0[0]), LOAD);
128 CLIB_PREFETCH (p3->data, sizeof (ip1[0]), LOAD);
131 to_next[0] = pi0 = from[0];
132 to_next[1] = pi1 = from[1];
138 p0 = vlib_get_buffer (vm, pi0);
139 p1 = vlib_get_buffer (vm, pi1);
141 ip0 = vlib_buffer_get_current (p0);
142 ip1 = vlib_buffer_get_current (p1);
144 sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
145 sw_if_index1 = vnet_buffer (p1)->sw_if_index[VLIB_RX];
147 error0 = error1 = IP4_ERROR_NONE;
149 if (PREDICT_FALSE (ip4_address_is_multicast (&ip0->dst_address)))
151 arc0 = lm->mcast_feature_arc_index;
152 next0 = IP4_INPUT_NEXT_LOOKUP_MULTICAST;
156 arc0 = lm->ucast_feature_arc_index;
157 next0 = IP4_INPUT_NEXT_LOOKUP;
158 if (PREDICT_FALSE (ip0->ttl < 1))
159 error0 = IP4_ERROR_TIME_EXPIRED;
162 if (PREDICT_FALSE (ip4_address_is_multicast (&ip1->dst_address)))
164 arc1 = lm->mcast_feature_arc_index;
165 next1 = IP4_INPUT_NEXT_LOOKUP_MULTICAST;
169 arc1 = lm->ucast_feature_arc_index;
170 next1 = IP4_INPUT_NEXT_LOOKUP;
171 if (PREDICT_FALSE (ip1->ttl < 1))
172 error1 = IP4_ERROR_TIME_EXPIRED;
175 vnet_buffer (p0)->ip.adj_index[VLIB_RX] = ~0;
176 vnet_buffer (p1)->ip.adj_index[VLIB_RX] = ~0;
178 vnet_feature_arc_start (arc0, sw_if_index0, &next0, p0);
179 vnet_feature_arc_start (arc1, sw_if_index1, &next1, p1);
181 vlib_increment_simple_counter (cm, cpu_index, sw_if_index0, 1);
182 vlib_increment_simple_counter (cm, cpu_index, sw_if_index1, 1);
184 /* Punt packets with options or wrong version. */
185 if (PREDICT_FALSE (ip0->ip_version_and_header_length != 0x45))
186 error0 = (ip0->ip_version_and_header_length & 0xf) != 5 ?
187 IP4_ERROR_OPTIONS : IP4_ERROR_VERSION;
189 if (PREDICT_FALSE (ip1->ip_version_and_header_length != 0x45))
190 error1 = (ip1->ip_version_and_header_length & 0xf) != 5 ?
191 IP4_ERROR_OPTIONS : IP4_ERROR_VERSION;
193 /* Verify header checksum. */
196 ip_csum_t sum0, sum1;
198 ip4_partial_header_checksum_x1 (ip0, sum0);
199 ip4_partial_header_checksum_x1 (ip1, sum1);
201 error0 = 0xffff != ip_csum_fold (sum0) ?
202 IP4_ERROR_BAD_CHECKSUM : error0;
203 error1 = 0xffff != ip_csum_fold (sum1) ?
204 IP4_ERROR_BAD_CHECKSUM : error1;
207 /* Drop fragmentation offset 1 packets. */
208 error0 = ip4_get_fragment_offset (ip0) == 1 ?
209 IP4_ERROR_FRAGMENT_OFFSET_ONE : error0;
210 error1 = ip4_get_fragment_offset (ip1) == 1 ?
211 IP4_ERROR_FRAGMENT_OFFSET_ONE : error1;
213 /* Verify lengths. */
214 ip_len0 = clib_net_to_host_u16 (ip0->length);
215 ip_len1 = clib_net_to_host_u16 (ip1->length);
217 /* IP length must be at least minimal IP header. */
218 error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0;
219 error1 = ip_len1 < sizeof (ip1[0]) ? IP4_ERROR_TOO_SHORT : error1;
221 cur_len0 = vlib_buffer_length_in_chain (vm, p0);
222 cur_len1 = vlib_buffer_length_in_chain (vm, p1);
224 len_diff0 = cur_len0 - ip_len0;
225 len_diff1 = cur_len1 - ip_len1;
227 error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0;
228 error1 = len_diff1 < 0 ? IP4_ERROR_BAD_LENGTH : error1;
230 p0->error = error_node->errors[error0];
231 p1->error = error_node->errors[error1];
233 if (PREDICT_FALSE (error0 != IP4_ERROR_NONE))
235 if (error0 == IP4_ERROR_TIME_EXPIRED)
237 icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded,
238 ICMP4_time_exceeded_ttl_exceeded_in_transit,
240 next0 = IP4_INPUT_NEXT_ICMP_ERROR;
243 next0 = error0 != IP4_ERROR_OPTIONS ?
244 IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
246 if (PREDICT_FALSE (error1 != IP4_ERROR_NONE))
248 if (error1 == IP4_ERROR_TIME_EXPIRED)
250 icmp4_error_set_vnet_buffer (p1, ICMP4_time_exceeded,
251 ICMP4_time_exceeded_ttl_exceeded_in_transit,
253 next1 = IP4_INPUT_NEXT_ICMP_ERROR;
256 next1 = error1 != IP4_ERROR_OPTIONS ?
257 IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
260 vlib_validate_buffer_enqueue_x2 (vm, node, next_index,
261 to_next, n_left_to_next,
262 pi0, pi1, next0, next1);
264 while (n_left_from > 0 && n_left_to_next > 0)
268 u32 sw_if_index0, pi0, ip_len0, cur_len0, next0;
279 p0 = vlib_get_buffer (vm, pi0);
280 ip0 = vlib_buffer_get_current (p0);
282 sw_if_index0 = vnet_buffer (p0)->sw_if_index[VLIB_RX];
284 error0 = IP4_ERROR_NONE;
286 if (PREDICT_FALSE (ip4_address_is_multicast (&ip0->dst_address)))
288 arc0 = lm->mcast_feature_arc_index;
289 next0 = IP4_INPUT_NEXT_LOOKUP_MULTICAST;
293 arc0 = lm->ucast_feature_arc_index;
294 next0 = IP4_INPUT_NEXT_LOOKUP;
295 if (PREDICT_FALSE (ip0->ttl < 1))
296 error0 = IP4_ERROR_TIME_EXPIRED;
299 vnet_buffer (p0)->ip.adj_index[VLIB_RX] = ~0;
300 vnet_feature_arc_start (arc0, sw_if_index0, &next0, p0);
302 vlib_increment_simple_counter (cm, cpu_index, sw_if_index0, 1);
304 /* Punt packets with options or wrong version. */
305 if (PREDICT_FALSE (ip0->ip_version_and_header_length != 0x45))
306 error0 = (ip0->ip_version_and_header_length & 0xf) != 5 ?
307 IP4_ERROR_OPTIONS : IP4_ERROR_VERSION;
309 /* Verify header checksum. */
314 ip4_partial_header_checksum_x1 (ip0, sum0);
317 ip_csum_fold (sum0) ? IP4_ERROR_BAD_CHECKSUM : error0;
320 /* Drop fragmentation offset 1 packets. */
322 ip4_get_fragment_offset (ip0) ==
323 1 ? IP4_ERROR_FRAGMENT_OFFSET_ONE : error0;
325 /* Verify lengths. */
326 ip_len0 = clib_net_to_host_u16 (ip0->length);
328 /* IP length must be at least minimal IP header. */
329 error0 = ip_len0 < sizeof (ip0[0]) ? IP4_ERROR_TOO_SHORT : error0;
331 cur_len0 = vlib_buffer_length_in_chain (vm, p0);
332 len_diff0 = cur_len0 - ip_len0;
333 error0 = len_diff0 < 0 ? IP4_ERROR_BAD_LENGTH : error0;
335 p0->error = error_node->errors[error0];
336 if (PREDICT_FALSE (error0 != IP4_ERROR_NONE))
338 if (error0 == IP4_ERROR_TIME_EXPIRED)
340 icmp4_error_set_vnet_buffer (p0, ICMP4_time_exceeded,
341 ICMP4_time_exceeded_ttl_exceeded_in_transit,
343 next0 = IP4_INPUT_NEXT_ICMP_ERROR;
346 next0 = error0 != IP4_ERROR_OPTIONS ?
347 IP4_INPUT_NEXT_DROP : IP4_INPUT_NEXT_PUNT;
350 vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
351 to_next, n_left_to_next,
355 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
358 return frame->n_vectors;
361 /** \brief IPv4 input node.
364 This is the IPv4 input node: validates ip4 header checksums,
365 verifies ip header lengths, discards pkts with expired TTLs,
366 and sends pkts to the set of ip feature nodes configured on
369 @param vm vlib_main_t corresponding to the current thread
370 @param node vlib_node_runtime_t
371 @param frame vlib_frame_t whose contents should be dispatched
373 @par Graph mechanics: buffer metadata, next index usage
376 - vnet_feature_config_main_t cm corresponding to each pkt's dst address unicast /
378 - <code>b->current_config_index</code> corresponding to each pkt's
380 - This sets the per-packet graph trajectory, ensuring that
381 each packet visits the per-interface features in order.
383 - <code>vnet_buffer(b)->sw_if_index[VLIB_RX]</code>
384 - Indicates the @c sw_if_index value of the interface that the
385 packet was received on.
388 - <code>vnet_buffer(b)->ip.adj_index[VLIB_TX]</code>
389 - The lookup result adjacency index.
391 <em>Next Indices:</em>
392 - Dispatches pkts to the (first) feature node:
393 <code> vnet_get_config_data (... &next0 ...); </code>
397 ip4_input (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame)
399 return ip4_input_inline (vm, node, frame, /* verify_checksum */ 1);
403 ip4_input_no_checksum (vlib_main_t * vm,
404 vlib_node_runtime_t * node, vlib_frame_t * frame)
406 return ip4_input_inline (vm, node, frame, /* verify_checksum */ 0);
409 static char *ip4_error_strings[] = {
410 #define _(sym,string) string,
416 VLIB_REGISTER_NODE (ip4_input_node) = {
417 .function = ip4_input,
419 .vector_size = sizeof (u32),
421 .n_errors = IP4_N_ERROR,
422 .error_strings = ip4_error_strings,
424 .n_next_nodes = IP4_INPUT_N_NEXT,
426 [IP4_INPUT_NEXT_DROP] = "error-drop",
427 [IP4_INPUT_NEXT_PUNT] = "error-punt",
428 [IP4_INPUT_NEXT_LOOKUP] = "ip4-lookup",
429 [IP4_INPUT_NEXT_LOOKUP_MULTICAST] = "ip4-lookup-multicast",
430 [IP4_INPUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
433 .format_buffer = format_ip4_header,
434 .format_trace = format_ip4_input_trace,
438 VLIB_NODE_FUNCTION_MULTIARCH (ip4_input_node, ip4_input);
441 VLIB_REGISTER_NODE (ip4_input_no_checksum_node,static) = {
442 .function = ip4_input_no_checksum,
443 .name = "ip4-input-no-checksum",
444 .vector_size = sizeof (u32),
446 .n_next_nodes = IP4_INPUT_N_NEXT,
448 [IP4_INPUT_NEXT_DROP] = "error-drop",
449 [IP4_INPUT_NEXT_PUNT] = "error-punt",
450 [IP4_INPUT_NEXT_LOOKUP] = "ip4-lookup",
451 [IP4_INPUT_NEXT_LOOKUP_MULTICAST] = "ip4-lookup-multicast",
452 [IP4_INPUT_NEXT_ICMP_ERROR] = "ip4-icmp-error",
455 .format_buffer = format_ip4_header,
456 .format_trace = format_ip4_input_trace,
460 VLIB_NODE_FUNCTION_MULTIARCH (ip4_input_no_checksum_node,
461 ip4_input_no_checksum);
463 static clib_error_t *
464 ip4_init (vlib_main_t * vm)
468 ethernet_register_input_type (vm, ETHERNET_TYPE_IP4, ip4_input_node.index);
469 ppp_register_input_protocol (vm, PPP_PROTOCOL_ip4, ip4_input_node.index);
470 hdlc_register_input_protocol (vm, HDLC_PROTOCOL_ip4, ip4_input_node.index);
474 pn = pg_get_node (ip4_input_node.index);
475 pn->unformat_edit = unformat_pg_ip4_header;
476 pn = pg_get_node (ip4_input_no_checksum_node.index);
477 pn->unformat_edit = unformat_pg_ip4_header;
480 if ((error = vlib_call_init_function (vm, ip4_cli_init)))
483 if ((error = vlib_call_init_function (vm, ip4_source_check_init)))
486 if ((error = vlib_call_init_function
487 (vm, ip4_source_and_port_range_check_init)))
490 /* Set flow hash to something non-zero. */
491 ip4_main.flow_hash_seed = 0xdeadbeef;
493 /* Default TTL for packets we generate. */
494 ip4_main.host_config.ttl = 64;
499 VLIB_INIT_FUNCTION (ip4_init);
502 * fd.io coding-style-patch-verification: ON
505 * eval: (c-set-style "gnu")