2 *------------------------------------------------------------------
3 * af_packet.c - linux kernel packet interface
5 * Copyright (c) 2016 Cisco and/or its affiliates.
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at:
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 *------------------------------------------------------------------
20 #include <linux/if_packet.h>
22 #include <vlib/vlib.h>
23 #include <vlib/unix/unix.h>
24 #include <vnet/ip/ip.h>
25 #include <vnet/ethernet/ethernet.h>
26 #include <vnet/interface/rx_queue_funcs.h>
27 #include <vnet/feature/feature.h>
28 #include <vnet/ethernet/packet.h>
30 #include <vnet/devices/af_packet/af_packet.h>
31 #include <vnet/devices/virtio/virtio_std.h>
33 #define foreach_af_packet_input_error \
34 _ (PARTIAL_PKT, "partial packet") \
35 _ (TIMEDOUT_BLK, "timed out block") \
36 _ (TOTAL_RECV_BLK, "total received block")
39 #define _(f,s) AF_PACKET_INPUT_ERROR_##f,
40 foreach_af_packet_input_error
42 AF_PACKET_INPUT_N_ERROR,
43 } af_packet_input_error_t;
45 static char *af_packet_input_error_strings[] = {
47 foreach_af_packet_input_error
61 vnet_virtio_net_hdr_t vnet_hdr;
62 } af_packet_input_trace_t;
65 format_af_packet_input_trace (u8 * s, va_list * args)
67 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
68 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
69 af_packet_input_trace_t *t = va_arg (*args, af_packet_input_trace_t *);
70 u32 indent = format_get_indent (s);
72 s = format (s, "af_packet: hw_if_index %d rx-queue %u next-index %d",
73 t->hw_if_index, t->queue_id, t->next_index);
76 s, "\n%Ublock %u:\n%Uaddress %p version %u seq_num %lu pkt_num %u",
77 format_white_space, indent + 2, t->block, format_white_space, indent + 4,
78 t->block_start, t->bd.version, t->bd.hdr.bh1.seq_num, t->pkt_num);
81 "\n%Utpacket3_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u"
82 "\n%Usec 0x%x nsec 0x%x vlan %U"
83 #ifdef TP_STATUS_VLAN_TPID_VALID
87 format_white_space, indent + 2, format_white_space, indent + 4,
88 t->tph.tp_status, t->tph.tp_len, t->tph.tp_snaplen, t->tph.tp_mac,
89 t->tph.tp_net, format_white_space, indent + 4, t->tph.tp_sec,
90 t->tph.tp_nsec, format_ethernet_vlan_tci, t->tph.hv1.tp_vlan_tci
91 #ifdef TP_STATUS_VLAN_TPID_VALID
93 t->tph.hv1.tp_vlan_tpid
98 "\n%Uvnet-hdr:\n%Uflags 0x%02x gso_type 0x%02x hdr_len %u"
99 "\n%Ugso_size %u csum_start %u csum_offset %u",
100 format_white_space, indent + 2, format_white_space, indent + 4,
101 t->vnet_hdr.flags, t->vnet_hdr.gso_type, t->vnet_hdr.hdr_len,
102 format_white_space, indent + 4, t->vnet_hdr.gso_size,
103 t->vnet_hdr.csum_start, t->vnet_hdr.csum_offset);
108 buffer_add_to_chain (vlib_buffer_t *b, vlib_buffer_t *first_b,
109 vlib_buffer_t *prev_b, u32 bi)
111 /* update first buffer */
112 first_b->total_length_not_including_first_buffer += b->current_length;
114 /* update previous buffer */
115 prev_b->next_buffer = bi;
116 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
118 /* update current buffer */
122 static_always_inline void
123 fill_gso_offload (vlib_buffer_t *b, u32 gso_size, u8 l4_hdr_sz)
125 b->flags |= VNET_BUFFER_F_GSO;
126 vnet_buffer2 (b)->gso_size = gso_size;
127 vnet_buffer2 (b)->gso_l4_hdr_sz = l4_hdr_sz;
130 static_always_inline void
131 fill_cksum_offload (vlib_buffer_t *b, u8 *l4_hdr_sz, u8 is_ip)
133 vnet_buffer_oflags_t oflags = 0;
140 switch (b->data[0] & 0xf0)
143 ethertype = ETHERNET_TYPE_IP4;
146 ethertype = ETHERNET_TYPE_IP6;
152 ethernet_header_t *eth = vlib_buffer_get_current (b);
153 ethertype = clib_net_to_host_u16 (eth->type);
154 l2hdr_sz = sizeof (ethernet_header_t);
155 if (ethernet_frame_is_tagged (ethertype))
157 ethernet_vlan_header_t *vlan = (ethernet_vlan_header_t *) (eth + 1);
159 ethertype = clib_net_to_host_u16 (vlan->type);
160 l2hdr_sz += sizeof (*vlan);
161 if (ethertype == ETHERNET_TYPE_VLAN)
164 ethertype = clib_net_to_host_u16 (vlan->type);
165 l2hdr_sz += sizeof (*vlan);
170 vnet_buffer (b)->l2_hdr_offset = 0;
171 vnet_buffer (b)->l3_hdr_offset = l2hdr_sz;
173 if (ethertype == ETHERNET_TYPE_IP4)
175 ip4_header_t *ip4 = (vlib_buffer_get_current (b) + l2hdr_sz);
176 vnet_buffer (b)->l4_hdr_offset = l2hdr_sz + ip4_header_bytes (ip4);
177 b->flags |= (VNET_BUFFER_F_IS_IP4 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID |
178 VNET_BUFFER_F_L3_HDR_OFFSET_VALID |
179 VNET_BUFFER_F_L4_HDR_OFFSET_VALID);
181 l4_proto = ip4->protocol;
183 else if (ethertype == ETHERNET_TYPE_IP6)
185 ip6_header_t *ip6 = (vlib_buffer_get_current (b) + l2hdr_sz);
186 b->flags |= (VNET_BUFFER_F_IS_IP6 | VNET_BUFFER_F_L2_HDR_OFFSET_VALID |
187 VNET_BUFFER_F_L3_HDR_OFFSET_VALID |
188 VNET_BUFFER_F_L4_HDR_OFFSET_VALID);
189 u16 ip6_hdr_len = sizeof (ip6_header_t);
191 if (ip6_ext_hdr (ip6->protocol))
193 ip6_ext_header_t *p = (void *) (ip6 + 1);
194 ip6_hdr_len += ip6_ext_header_len (p);
195 while (ip6_ext_hdr (p->next_hdr))
197 ip6_hdr_len += ip6_ext_header_len (p);
198 p = ip6_ext_next_header (p);
200 l4_proto = p->next_hdr;
203 l4_proto = ip6->protocol;
204 vnet_buffer (b)->l4_hdr_offset = l2hdr_sz + ip6_hdr_len;
207 if (l4_proto == IP_PROTOCOL_TCP)
209 oflags |= VNET_BUFFER_OFFLOAD_F_TCP_CKSUM;
210 tcp_header_t *tcp = (tcp_header_t *) (vlib_buffer_get_current (b) +
211 vnet_buffer (b)->l4_hdr_offset);
212 *l4_hdr_sz = tcp_header_bytes (tcp);
214 else if (l4_proto == IP_PROTOCOL_UDP)
216 oflags |= VNET_BUFFER_OFFLOAD_F_UDP_CKSUM;
217 *l4_hdr_sz = sizeof (udp_header_t);
221 vnet_buffer_offload_flags_set (b, oflags);
225 af_packet_device_input_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
226 vlib_frame_t *frame, af_packet_if_t *apif,
227 u16 queue_id, u8 is_cksum_gso_enabled)
229 af_packet_main_t *apm = &af_packet_main;
230 af_packet_queue_t *rx_queue = vec_elt_at_index (apif->rx_queues, queue_id);
234 u32 n_rx_packets = 0;
236 u32 timedout_blk = 0;
239 u32 block = rx_queue->next_rx_block;
240 u32 block_nr = rx_queue->rx_req->tp_block_nr;
242 uword n_trace = vlib_get_trace_count (vm, node);
243 u32 thread_index = vm->thread_index;
244 u32 n_buffer_bytes = vlib_buffer_get_default_data_size (vm);
245 u32 min_bufs = rx_queue->rx_req->tp_frame_size / n_buffer_bytes;
247 u32 rx_frame_offset = 0;
248 block_desc_t *bd = 0;
250 u8 is_ip = (apif->mode == AF_PACKET_IF_MODE_IP);
253 next_index = VNET_DEVICE_INPUT_NEXT_IP4_INPUT;
256 next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
257 if (PREDICT_FALSE (apif->per_interface_next_index != ~0))
258 next_index = apif->per_interface_next_index;
260 /* redirect if feature path enabled */
261 vnet_feature_start_device_input_x1 (apif->sw_if_index, &next_index, &bt);
264 if ((((block_desc_t *) (block_start = rx_queue->rx_ring[block]))
265 ->hdr.bh1.block_status &
266 TP_STATUS_USER) != 0)
269 bd = (block_desc_t *) block_start;
273 if (TP_STATUS_BLK_TMO & bd->hdr.bh1.block_status)
276 if (PREDICT_FALSE (rx_queue->is_rx_pending))
278 num_pkts = rx_queue->num_rx_pkts;
279 rx_frame_offset = rx_queue->rx_frame_offset;
280 rx_queue->is_rx_pending = 0;
284 num_pkts = bd->hdr.bh1.num_pkts;
285 rx_frame_offset = sizeof (block_desc_t);
288 n_required = clib_max (num_pkts, VLIB_FRAME_SIZE);
289 n_free_bufs = vec_len (apm->rx_buffers[thread_index]);
290 if (PREDICT_FALSE (n_free_bufs < n_required))
292 vec_validate (apm->rx_buffers[thread_index],
293 n_required + n_free_bufs - 1);
294 n_free_bufs += vlib_buffer_alloc (
295 vm, &apm->rx_buffers[thread_index][n_free_bufs], n_required);
296 _vec_len (apm->rx_buffers[thread_index]) = n_free_bufs;
299 while (num_pkts && (n_free_bufs >= min_bufs))
301 u32 next0 = next_index;
304 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
306 while (num_pkts && n_left_to_next && (n_free_bufs >= min_bufs))
308 tph = (tpacket3_hdr_t *) (block_start + rx_frame_offset);
311 CLIB_PREFETCH (block_start + rx_frame_offset +
313 2 * CLIB_CACHE_LINE_BYTES, LOAD);
315 vlib_buffer_t *b0 = 0, *first_b0 = 0, *prev_b0 = 0;
316 vnet_virtio_net_hdr_t *vnet_hdr = 0;
317 u32 data_len = tph->tp_snaplen;
319 u32 bi0 = ~0, first_bi0 = ~0;
322 if (is_cksum_gso_enabled)
324 (vnet_virtio_net_hdr_t *) ((u8 *) tph + tph->tp_mac -
325 sizeof (vnet_virtio_net_hdr_t));
327 // save current state and return
328 if (PREDICT_FALSE (((data_len / n_buffer_bytes) + 1) >
329 vec_len (apm->rx_buffers[thread_index])))
331 rx_queue->rx_frame_offset = rx_frame_offset;
332 rx_queue->num_rx_pkts = num_pkts;
333 rx_queue->is_rx_pending = 1;
334 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
340 /* grab free buffer */
341 u32 last_empty_buffer =
342 vec_len (apm->rx_buffers[thread_index]) - 1;
343 bi0 = apm->rx_buffers[thread_index][last_empty_buffer];
344 _vec_len (apm->rx_buffers[thread_index]) = last_empty_buffer;
349 data_len > n_buffer_bytes ? n_buffer_bytes : data_len;
351 u32 bytes_copied = 0;
353 b0 = vlib_get_buffer (vm, bi0);
354 b0->current_data = 0;
356 /* Kernel removes VLAN headers, so reconstruct VLAN */
357 if (PREDICT_FALSE (tph->tp_status & TP_STATUS_VLAN_VALID))
359 if (PREDICT_TRUE (offset == 0))
361 clib_memcpy_fast (vlib_buffer_get_current (b0),
362 (u8 *) tph + tph->tp_mac,
363 sizeof (ethernet_header_t));
364 ethernet_header_t *eth =
365 vlib_buffer_get_current (b0);
366 ethernet_vlan_header_t *vlan =
367 (ethernet_vlan_header_t *) (eth + 1);
368 vlan->priority_cfi_and_id =
369 clib_host_to_net_u16 (tph->hv1.tp_vlan_tci);
370 vlan->type = eth->type;
372 clib_host_to_net_u16 (ETHERNET_TYPE_VLAN);
373 vlan_len = sizeof (ethernet_vlan_header_t);
374 bytes_copied = sizeof (ethernet_header_t);
377 clib_memcpy_fast (((u8 *) vlib_buffer_get_current (b0)) +
378 bytes_copied + vlan_len,
379 (u8 *) tph + tph->tp_mac + offset +
381 (bytes_to_copy - bytes_copied));
383 /* fill buffer header */
384 b0->current_length = bytes_to_copy + vlan_len;
388 b0->total_length_not_including_first_buffer = 0;
389 b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
390 vnet_buffer (b0)->sw_if_index[VLIB_RX] =
392 vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~0;
395 if (is_cksum_gso_enabled)
397 if (vnet_hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM)
398 fill_cksum_offload (first_b0, &l4_hdr_sz, is_ip);
399 if (vnet_hdr->gso_type & (VIRTIO_NET_HDR_GSO_TCPV4 |
400 VIRTIO_NET_HDR_GSO_TCPV6))
401 fill_gso_offload (first_b0, vnet_hdr->gso_size,
406 buffer_add_to_chain (b0, first_b0, prev_b0, bi0);
409 offset += bytes_to_copy;
410 data_len -= bytes_to_copy;
413 n_rx_bytes += tph->tp_snaplen;
414 to_next[0] = first_bi0;
418 /* drop partial packets */
419 if (PREDICT_FALSE (tph->tp_len != tph->tp_snaplen))
421 next0 = VNET_DEVICE_INPUT_NEXT_DROP;
423 node->errors[AF_PACKET_INPUT_ERROR_PARTIAL_PKT];
427 if (PREDICT_FALSE (apif->mode == AF_PACKET_IF_MODE_IP))
429 switch (first_b0->data[0] & 0xf0)
432 next0 = VNET_DEVICE_INPUT_NEXT_IP4_INPUT;
435 next0 = VNET_DEVICE_INPUT_NEXT_IP6_INPUT;
438 next0 = VNET_DEVICE_INPUT_NEXT_DROP;
441 if (PREDICT_FALSE (apif->per_interface_next_index != ~0))
442 next0 = apif->per_interface_next_index;
446 /* copy feature arc data from template */
447 first_b0->current_config_index = bt.current_config_index;
448 vnet_buffer (first_b0)->feature_arc_index =
449 vnet_buffer (&bt)->feature_arc_index;
454 if (PREDICT_FALSE (n_trace > 0 &&
455 vlib_trace_buffer (vm, node, next0, first_b0,
456 /* follow_chain */ 0)))
458 af_packet_input_trace_t *tr;
459 vlib_set_trace_count (vm, node, --n_trace);
460 tr = vlib_add_trace (vm, node, first_b0, sizeof (*tr));
461 tr->next_index = next0;
462 tr->hw_if_index = apif->hw_if_index;
463 tr->queue_id = queue_id;
465 tr->block_start = bd;
466 tr->pkt_num = bd->hdr.bh1.num_pkts - num_pkts;
467 clib_memcpy_fast (&tr->bd, bd, sizeof (block_desc_t));
468 clib_memcpy_fast (&tr->tph, tph, sizeof (tpacket3_hdr_t));
469 if (is_cksum_gso_enabled)
470 clib_memcpy_fast (&tr->vnet_hdr, vnet_hdr,
471 sizeof (vnet_virtio_net_hdr_t));
473 clib_memset_u8 (&tr->vnet_hdr, 0,
474 sizeof (vnet_virtio_net_hdr_t));
477 /* enque and take next packet */
478 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
479 n_left_to_next, first_bi0,
484 rx_frame_offset += tph->tp_next_offset;
487 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
490 if (PREDICT_TRUE (num_pkts == 0))
492 bd->hdr.bh1.block_status = TP_STATUS_KERNEL;
493 block = (block + 1) % block_nr;
497 rx_queue->rx_frame_offset = rx_frame_offset;
498 rx_queue->num_rx_pkts = num_pkts;
499 rx_queue->is_rx_pending = 1;
503 rx_queue->next_rx_block = block;
507 if ((((block_desc_t *) (block_start = rx_queue->rx_ring[block]))
508 ->hdr.bh1.block_status &
509 TP_STATUS_USER) != 0)
510 vlib_node_set_state (vm, node->node_index, VLIB_NODE_STATE_POLLING);
512 vlib_node_set_state (vm, node->node_index, VLIB_NODE_STATE_INTERRUPT);
514 vlib_error_count (vm, node->node_index, AF_PACKET_INPUT_ERROR_TOTAL_RECV_BLK,
516 vlib_error_count (vm, node->node_index, AF_PACKET_INPUT_ERROR_TIMEDOUT_BLK,
519 vlib_increment_combined_counter
520 (vnet_get_main ()->interface_main.combined_sw_if_counters
521 + VNET_INTERFACE_COUNTER_RX,
522 vlib_get_thread_index (), apif->hw_if_index, n_rx_packets, n_rx_bytes);
524 vnet_device_increment_rx_packets (thread_index, n_rx_packets);
528 VLIB_NODE_FN (af_packet_input_node) (vlib_main_t * vm,
529 vlib_node_runtime_t * node,
530 vlib_frame_t * frame)
532 u32 n_rx_packets = 0;
533 af_packet_main_t *apm = &af_packet_main;
534 vnet_hw_if_rxq_poll_vector_t *pv;
535 pv = vnet_hw_if_get_rxq_poll_vector (vm, node);
536 for (int i = 0; i < vec_len (pv); i++)
538 af_packet_if_t *apif;
539 apif = vec_elt_at_index (apm->interfaces, pv[i].dev_instance);
540 if (apif->is_admin_up)
542 if (apif->is_cksum_gso_enabled)
543 n_rx_packets += af_packet_device_input_fn (vm, node, frame, apif,
546 n_rx_packets += af_packet_device_input_fn (vm, node, frame, apif,
553 VLIB_REGISTER_NODE (af_packet_input_node) = {
554 .name = "af-packet-input",
555 .flags = VLIB_NODE_FLAG_TRACE_SUPPORTED,
556 .sibling_of = "device-input",
557 .format_trace = format_af_packet_input_trace,
558 .type = VLIB_NODE_TYPE_INPUT,
559 .state = VLIB_NODE_STATE_INTERRUPT,
560 .n_errors = AF_PACKET_INPUT_N_ERROR,
561 .error_strings = af_packet_input_error_strings,
566 * fd.io coding-style-patch-verification: ON
569 * eval: (c-set-style "gnu")