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/devices/devices.h>
27 #include <vnet/feature/feature.h>
28 #include <vnet/ethernet/packet.h>
30 #include <vnet/devices/af_packet/af_packet.h>
32 #define foreach_af_packet_input_error
36 #define _(f,s) AF_PACKET_INPUT_ERROR_##f,
37 foreach_af_packet_input_error
39 AF_PACKET_INPUT_N_ERROR,
40 } af_packet_input_error_t;
42 static char *af_packet_input_error_strings[] = {
44 foreach_af_packet_input_error
53 struct tpacket2_hdr tph;
54 } af_packet_input_trace_t;
57 format_af_packet_input_trace (u8 * s, va_list * args)
59 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
60 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
61 af_packet_input_trace_t *t = va_arg (*args, af_packet_input_trace_t *);
62 u32 indent = format_get_indent (s);
64 s = format (s, "af_packet: hw_if_index %d next-index %d",
65 t->hw_if_index, t->next_index);
69 "\n%Utpacket2_hdr:\n%Ustatus 0x%x len %u snaplen %u mac %u net %u"
70 "\n%Usec 0x%x nsec 0x%x vlan %U"
71 #ifdef TP_STATUS_VLAN_TPID_VALID
75 format_white_space, indent + 2,
76 format_white_space, indent + 4,
82 format_white_space, indent + 4,
84 t->tph.tp_nsec, format_ethernet_vlan_tci, t->tph.tp_vlan_tci
85 #ifdef TP_STATUS_VLAN_TPID_VALID
93 buffer_add_to_chain (vlib_main_t * vm, u32 bi, u32 first_bi, u32 prev_bi)
95 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
96 vlib_buffer_t *first_b = vlib_get_buffer (vm, first_bi);
97 vlib_buffer_t *prev_b = vlib_get_buffer (vm, prev_bi);
99 /* update first buffer */
100 first_b->total_length_not_including_first_buffer += b->current_length;
102 /* update previous buffer */
103 prev_b->next_buffer = bi;
104 prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
106 /* update current buffer */
110 static_always_inline void
111 mark_tcp_udp_cksum_calc (vlib_buffer_t * b)
113 ethernet_header_t *eth = vlib_buffer_get_current (b);
114 if (clib_net_to_host_u16 (eth->type) == ETHERNET_TYPE_IP4)
117 (vlib_buffer_get_current (b) + sizeof (ethernet_header_t));
118 b->flags |= VNET_BUFFER_F_IS_IP4;
119 if (ip4->protocol == IP_PROTOCOL_TCP)
121 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
123 *) (vlib_buffer_get_current (b) +
124 sizeof (ethernet_header_t) +
125 ip4_header_bytes (ip4)))->checksum = 0;
127 else if (ip4->protocol == IP_PROTOCOL_UDP)
129 b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
131 *) (vlib_buffer_get_current (b) +
132 sizeof (ethernet_header_t) +
133 ip4_header_bytes (ip4)))->checksum = 0;
135 vnet_buffer (b)->l3_hdr_offset = sizeof (ethernet_header_t);
136 vnet_buffer (b)->l4_hdr_offset =
137 sizeof (ethernet_header_t) + ip4_header_bytes (ip4);
139 else if (clib_net_to_host_u16 (eth->type) == ETHERNET_TYPE_IP6)
142 (vlib_buffer_get_current (b) + sizeof (ethernet_header_t));
143 b->flags |= VNET_BUFFER_F_IS_IP6;
144 u16 ip6_hdr_len = sizeof (ip6_header_t);
145 if (ip6_ext_hdr (ip6->protocol))
147 ip6_ext_header_t *p = (void *) (ip6 + 1);
148 ip6_hdr_len += ip6_ext_header_len (p);
149 while (ip6_ext_hdr (p->next_hdr))
151 ip6_hdr_len += ip6_ext_header_len (p);
152 p = ip6_ext_next_header (p);
155 if (ip6->protocol == IP_PROTOCOL_TCP)
157 b->flags |= VNET_BUFFER_F_OFFLOAD_TCP_CKSUM;
159 *) (vlib_buffer_get_current (b) +
160 sizeof (ethernet_header_t) + ip6_hdr_len))->checksum = 0;
162 else if (ip6->protocol == IP_PROTOCOL_UDP)
164 b->flags |= VNET_BUFFER_F_OFFLOAD_UDP_CKSUM;
166 *) (vlib_buffer_get_current (b) +
167 sizeof (ethernet_header_t) + ip6_hdr_len))->checksum = 0;
169 vnet_buffer (b)->l3_hdr_offset = sizeof (ethernet_header_t);
170 vnet_buffer (b)->l4_hdr_offset =
171 sizeof (ethernet_header_t) + ip6_hdr_len;
176 af_packet_device_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
177 vlib_frame_t * frame, af_packet_if_t * apif)
179 af_packet_main_t *apm = &af_packet_main;
180 struct tpacket2_hdr *tph;
181 u32 next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
185 u32 n_rx_packets = 0;
188 u32 block_size = apif->rx_req->tp_block_size;
189 u32 frame_size = apif->rx_req->tp_frame_size;
190 u32 frame_num = apif->rx_req->tp_frame_nr;
191 u8 *block_start = apif->rx_ring + block * block_size;
192 uword n_trace = vlib_get_trace_count (vm, node);
193 u32 thread_index = vlib_get_thread_index ();
194 u32 n_buffer_bytes = vlib_buffer_free_list_buffer_size (vm,
195 VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
196 u32 min_bufs = apif->rx_req->tp_frame_size / n_buffer_bytes;
198 if (apif->per_interface_next_index != ~0)
199 next_index = apif->per_interface_next_index;
201 n_free_bufs = vec_len (apm->rx_buffers[thread_index]);
202 if (PREDICT_FALSE (n_free_bufs < VLIB_FRAME_SIZE))
204 vec_validate (apm->rx_buffers[thread_index],
205 VLIB_FRAME_SIZE + n_free_bufs - 1);
207 vlib_buffer_alloc (vm, &apm->rx_buffers[thread_index][n_free_bufs],
209 _vec_len (apm->rx_buffers[thread_index]) = n_free_bufs;
212 rx_frame = apif->next_rx_frame;
213 tph = (struct tpacket2_hdr *) (block_start + rx_frame * frame_size);
214 while ((tph->tp_status & TP_STATUS_USER) && (n_free_bufs > min_bufs))
216 vlib_buffer_t *b0 = 0, *first_b0 = 0;
217 u32 next0 = next_index;
220 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
221 while ((tph->tp_status & TP_STATUS_USER) && (n_free_bufs > min_bufs) &&
224 u32 data_len = tph->tp_snaplen;
226 u32 bi0 = 0, first_bi0 = 0, prev_bi0;
230 /* grab free buffer */
231 u32 last_empty_buffer =
232 vec_len (apm->rx_buffers[thread_index]) - 1;
234 bi0 = apm->rx_buffers[thread_index][last_empty_buffer];
235 b0 = vlib_get_buffer (vm, bi0);
236 _vec_len (apm->rx_buffers[thread_index]) = last_empty_buffer;
241 data_len > n_buffer_bytes ? n_buffer_bytes : data_len;
243 u32 bytes_copied = 0;
244 b0->current_data = 0;
245 /* Kernel removes VLAN headers, so reconstruct VLAN */
246 if (PREDICT_FALSE (tph->tp_status & TP_STATUS_VLAN_VALID))
248 if (PREDICT_TRUE (offset == 0))
250 clib_memcpy (vlib_buffer_get_current (b0),
251 (u8 *) tph + tph->tp_mac,
252 sizeof (ethernet_header_t));
253 ethernet_header_t *eth = vlib_buffer_get_current (b0);
254 ethernet_vlan_header_t *vlan =
255 (ethernet_vlan_header_t *) (eth + 1);
256 vlan->priority_cfi_and_id =
257 clib_host_to_net_u16 (tph->tp_vlan_tci);
258 vlan->type = eth->type;
259 eth->type = clib_host_to_net_u16 (ETHERNET_TYPE_VLAN);
260 vlan_len = sizeof (ethernet_vlan_header_t);
261 bytes_copied = sizeof (ethernet_header_t);
264 clib_memcpy (((u8 *) vlib_buffer_get_current (b0)) +
265 bytes_copied + vlan_len,
266 (u8 *) tph + tph->tp_mac + offset + bytes_copied,
267 (bytes_to_copy - bytes_copied));
269 /* fill buffer header */
270 b0->current_length = bytes_to_copy + vlan_len;
274 b0->total_length_not_including_first_buffer = 0;
275 b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
276 vnet_buffer (b0)->sw_if_index[VLIB_RX] = apif->sw_if_index;
277 vnet_buffer (b0)->sw_if_index[VLIB_TX] = (u32) ~ 0;
279 first_b0 = vlib_get_buffer (vm, first_bi0);
280 if (tph->tp_status & TP_STATUS_CSUMNOTREADY)
281 mark_tcp_udp_cksum_calc (first_b0);
284 buffer_add_to_chain (vm, bi0, first_bi0, prev_bi0);
286 offset += bytes_to_copy;
287 data_len -= bytes_to_copy;
290 n_rx_bytes += tph->tp_snaplen;
291 to_next[0] = first_bi0;
296 VLIB_BUFFER_TRACE_TRAJECTORY_INIT (first_b0);
297 if (PREDICT_FALSE (n_trace > 0))
299 af_packet_input_trace_t *tr;
300 vlib_trace_buffer (vm, node, next0, first_b0, /* follow_chain */
302 vlib_set_trace_count (vm, node, --n_trace);
303 tr = vlib_add_trace (vm, node, first_b0, sizeof (*tr));
304 tr->next_index = next0;
305 tr->hw_if_index = apif->hw_if_index;
306 clib_memcpy (&tr->tph, tph, sizeof (struct tpacket2_hdr));
309 /* redirect if feature path enabled */
310 vnet_feature_start_device_input_x1 (apif->sw_if_index, &next0, b0);
312 /* enque and take next packet */
313 vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
314 n_left_to_next, first_bi0, next0);
317 tph->tp_status = TP_STATUS_KERNEL;
318 rx_frame = (rx_frame + 1) % frame_num;
319 tph = (struct tpacket2_hdr *) (block_start + rx_frame * frame_size);
322 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
325 apif->next_rx_frame = rx_frame;
327 vlib_increment_combined_counter
328 (vnet_get_main ()->interface_main.combined_sw_if_counters
329 + VNET_INTERFACE_COUNTER_RX,
330 vlib_get_thread_index (), apif->hw_if_index, n_rx_packets, n_rx_bytes);
332 vnet_device_increment_rx_packets (thread_index, n_rx_packets);
337 af_packet_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
338 vlib_frame_t * frame)
340 u32 n_rx_packets = 0;
341 af_packet_main_t *apm = &af_packet_main;
342 vnet_device_input_runtime_t *rt = (void *) node->runtime_data;
343 vnet_device_and_queue_t *dq;
345 foreach_device_and_queue (dq, rt->devices_and_queues)
347 af_packet_if_t *apif;
348 apif = vec_elt_at_index (apm->interfaces, dq->dev_instance);
349 if (apif->is_admin_up)
350 n_rx_packets += af_packet_device_input_fn (vm, node, frame, apif);
357 VLIB_REGISTER_NODE (af_packet_input_node) = {
358 .function = af_packet_input_fn,
359 .name = "af-packet-input",
360 .sibling_of = "device-input",
361 .format_trace = format_af_packet_input_trace,
362 .type = VLIB_NODE_TYPE_INPUT,
363 .state = VLIB_NODE_STATE_INTERRUPT,
364 .n_errors = AF_PACKET_INPUT_N_ERROR,
365 .error_strings = af_packet_input_error_strings,
368 VLIB_NODE_FUNCTION_MULTIARCH (af_packet_input_node, af_packet_input_fn)
373 * fd.io coding-style-patch-verification: ON
376 * eval: (c-set-style "gnu")