2 * sr_replicate.c: ipv6 segment routing replicator for multicast
4 * Copyright (c) 2016 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:
9 * http://www.apache.org/licenses/LICENSE-2.0
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.
19 * @brief Functions for replicating packets across SR tunnels.
21 * Leverages rte_pktmbuf_clone() so there is no memcpy for
22 * invariant parts of the packet.
24 * @note Currently requires DPDK
27 #if DPDK > 0 /* Cannot run replicate without DPDK */
28 #include <vlib/vlib.h>
29 #include <vnet/vnet.h>
30 #include <vnet/pg/pg.h>
31 #include <vnet/sr/sr.h>
32 #include <vnet/devices/dpdk/dpdk.h>
33 #include <vnet/ip/ip.h>
34 #include <vnet/fib/ip6_fib.h>
36 #include <vppinfra/hash.h>
37 #include <vppinfra/error.h>
38 #include <vppinfra/elog.h>
41 * @brief sr_replicate state.
47 vlib_main_t *vlib_main;
48 vnet_main_t *vnet_main;
49 } sr_replicate_main_t;
51 sr_replicate_main_t sr_replicate_main;
54 * @brief Information to display in packet trace.
59 ip6_address_t src, dst;
64 } sr_replicate_trace_t;
67 * @brief packet trace format function.
69 * @param *s u8 used for string output
70 * @param *args va_list structured input to va_arg to output @ref sr_replicate_trace_t
71 * @return *s u8 - formatted trace output
74 format_sr_replicate_trace (u8 * s, va_list * args)
76 CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
77 CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
78 sr_replicate_trace_t *t = va_arg (*args, sr_replicate_trace_t *);
79 ip6_sr_main_t *sm = &sr_main;
80 ip6_sr_tunnel_t *tun = pool_elt_at_index (sm->tunnels, t->tunnel_index);
81 ip6_fib_t *rx_fib, *tx_fib;
83 rx_fib = ip6_fib_get (tun->rx_fib_index);
84 tx_fib = ip6_fib_get (tun->tx_fib_index);
87 (s, "SR-REPLICATE: next %s ip6 src %U dst %U len %u\n"
88 " rx-fib-id %d tx-fib-id %d\n%U",
90 format_ip6_address, &t->src,
91 format_ip6_address, &t->dst, t->length,
92 rx_fib->table_id, tx_fib->table_id,
93 format_ip6_sr_header, t->sr, 0 /* print_hmac */ );
98 #define foreach_sr_replicate_error \
99 _(REPLICATED, "sr packets replicated") \
100 _(NO_BUFFERS, "error allocating buffers for replicas") \
101 _(NO_REPLICAS, "no replicas were needed") \
102 _(NO_BUFFER_DROPS, "sr no buffer drops")
105 * @brief Struct for SR replicate errors
109 #define _(sym,str) SR_REPLICATE_ERROR_##sym,
110 foreach_sr_replicate_error
112 SR_REPLICATE_N_ERROR,
113 } sr_replicate_error_t;
116 * @brief Error strings for SR replicate
118 static char *sr_replicate_error_strings[] = {
119 #define _(sym,string) string,
120 foreach_sr_replicate_error
125 * @brief Defines next-nodes for packet processing.
130 SR_REPLICATE_NEXT_IP6_LOOKUP,
132 } sr_replicate_next_t;
135 * @brief Single loop packet replicator.
138 * @param vm vlib_main_t
139 * @return frame->n_vectors uword
142 sr_replicate_node_fn (vlib_main_t * vm,
143 vlib_node_runtime_t * node, vlib_frame_t * frame)
145 u32 n_left_from, *from, *to_next;
146 sr_replicate_next_t next_index;
147 int pkts_replicated = 0;
148 ip6_sr_main_t *sm = &sr_main;
149 int no_buffer_drops = 0;
150 vlib_buffer_free_list_t *fl;
151 unsigned socket_id = rte_socket_id ();
152 vlib_buffer_main_t *bm = vm->buffer_main;
154 from = vlib_frame_vector_args (frame);
155 n_left_from = frame->n_vectors;
156 next_index = node->cached_next_index;
158 fl = vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
160 while (n_left_from > 0)
164 vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
166 while (n_left_from > 0 && n_left_to_next > 0)
169 vlib_buffer_t *b0, *orig_b0;
170 struct rte_mbuf *orig_mb0 = 0, *hdr_mb0 = 0, *clone0 = 0;
171 struct rte_mbuf **hdr_vec = 0, **rte_mbuf_vec = 0;
172 ip6_sr_policy_t *pol0 = 0;
173 ip6_sr_tunnel_t *t0 = 0;
174 ip6_sr_header_t *hdr_sr0 = 0;
175 ip6_header_t *ip0 = 0, *hdr_ip0 = 0;
176 int num_replicas = 0;
178 u32 len_bytes = sizeof (ip6_header_t);
179 u8 next_hdr, ip_next_hdr = IPPROTO_IPV6_ROUTE;
183 b0 = vlib_get_buffer (vm, bi0);
186 pol0 = pool_elt_at_index (sm->policies,
187 vnet_buffer (b0)->ip.save_protocol);
189 ip0 = vlib_buffer_get_current (b0);
190 /* Skip forward to the punch-in point */
191 vlib_buffer_advance (b0, sizeof (*ip0));
192 next_hdr = ip0->protocol;
194 /* HBH must immediately follow ipv6 header */
196 (ip0->protocol == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS))
198 ip6_hop_by_hop_ext_t *ext_hdr =
199 (ip6_hop_by_hop_ext_t *) ip6_next_header (ip0);
201 ext_hdr_len = ip6_ext_header_len ((ip6_ext_header_t *) ext_hdr);
202 len_bytes += ext_hdr_len;
203 next_hdr = ext_hdr->next_hdr;
204 ext_hdr->next_hdr = IPPROTO_IPV6_ROUTE;
205 ip_next_hdr = IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS;
206 /* Skip forward to the punch-in point */
207 vlib_buffer_advance (b0, ext_hdr_len);
211 orig_mb0 = rte_mbuf_from_vlib_buffer (b0);
213 i16 delta0 = vlib_buffer_length_in_chain (vm, orig_b0)
214 - (i16) orig_mb0->pkt_len;
216 u16 new_data_len0 = (u16) ((i16) orig_mb0->data_len + delta0);
217 u16 new_pkt_len0 = (u16) ((i16) orig_mb0->pkt_len + delta0);
219 orig_mb0->data_len = new_data_len0;
220 orig_mb0->pkt_len = new_pkt_len0;
221 orig_mb0->data_off += (u16) (b0->current_data);
224 Before entering loop determine if we can allocate:
225 - all the new HEADER RTE_MBUFs and assign them to a vector
228 if successful, then iterate over vectors of resources
231 num_replicas = vec_len (pol0->tunnel_indices);
233 if (PREDICT_FALSE (num_replicas == 0))
235 b0->error = node->errors[SR_REPLICATE_ERROR_NO_REPLICAS];
239 vec_reset_length (hdr_vec);
240 vec_reset_length (rte_mbuf_vec);
242 for (i = 0; i < num_replicas; i++)
245 struct rte_mbuf *clone0i;
246 vlib_buffer_t *clone0_c, *clone_b0;
248 t0 = vec_elt_at_index (sm->tunnels, pol0->tunnel_indices[i]);
249 hdr_mb0 = rte_pktmbuf_alloc (bm->pktmbuf_pools[socket_id]);
251 if (i < (num_replicas - 1))
253 /* Not the last tunnel to process */
254 clone0 = rte_pktmbuf_clone
255 (orig_mb0, bm->pktmbuf_pools[socket_id]);
261 while ((clone0->nb_segs >= 1) && (nb_seg < clone0->nb_segs))
264 clone_b0 = vlib_buffer_from_rte_mbuf (clone0i);
265 vlib_buffer_init_for_free_list (clone_b0, fl);
267 ASSERT ((clone_b0->flags & VLIB_BUFFER_NEXT_PRESENT) ==
269 ASSERT (clone_b0->current_data == 0);
271 clone_b0->current_data =
272 (clone0i->buf_addr + clone0i->data_off) -
273 (void *) clone_b0->data;
275 clone_b0->current_length = clone0i->data_len;
276 if (PREDICT_FALSE (clone0_c != NULL))
278 clone0_c->flags |= VLIB_BUFFER_NEXT_PRESENT;
279 clone0_c->next_buffer =
280 vlib_get_buffer_index (vm, clone_b0);
283 clone0i = clone0i->next;
288 /* First tunnel to process, use original MB */
292 if (PREDICT_FALSE (!clone0 || !hdr_mb0))
295 b0->error = node->errors[SR_REPLICATE_ERROR_NO_BUFFERS];
297 vec_foreach_index (i, rte_mbuf_vec)
299 rte_pktmbuf_free (rte_mbuf_vec[i]);
301 vec_free (rte_mbuf_vec);
303 vec_foreach_index (i, hdr_vec)
305 rte_pktmbuf_free (hdr_vec[i]);
312 vec_add1 (hdr_vec, hdr_mb0);
313 vec_add1 (rte_mbuf_vec, clone0);
317 for (i = 0; i < num_replicas; i++)
319 vlib_buffer_t *hdr_b0;
322 t0 = vec_elt_at_index (sm->tunnels, pol0->tunnel_indices[i]);
324 hdr_mb0 = hdr_vec[i];
325 clone0 = rte_mbuf_vec[i];
327 hdr_mb0->data_len = len_bytes + vec_len (t0->rewrite);
328 hdr_mb0->pkt_len = hdr_mb0->data_len +
329 vlib_buffer_length_in_chain (vm, orig_b0);
331 hdr_b0 = vlib_buffer_from_rte_mbuf (hdr_mb0);
333 vlib_buffer_init_for_free_list (hdr_b0, fl);
335 memcpy (hdr_b0->data, ip0, len_bytes);
336 memcpy (hdr_b0->data + len_bytes, t0->rewrite,
337 vec_len (t0->rewrite));
339 hdr_b0->current_data = 0;
340 hdr_b0->current_length = len_bytes + vec_len (t0->rewrite);
341 hdr_b0->flags = orig_b0->flags | VLIB_BUFFER_NEXT_PRESENT;
342 hdr_b0->trace_index = orig_b0->trace_index;
343 vnet_buffer (hdr_b0)->l2_classify.opaque_index = 0;
345 hdr_b0->total_length_not_including_first_buffer =
346 hdr_mb0->pkt_len - hdr_b0->current_length;
347 vnet_buffer (hdr_b0)->sw_if_index[VLIB_TX] = t0->tx_fib_index;
349 hdr_ip0 = (ip6_header_t *) hdr_b0->data;
350 new_l0 = clib_net_to_host_u16 (ip0->payload_length) +
351 vec_len (t0->rewrite);
352 hdr_ip0->payload_length = clib_host_to_net_u16 (new_l0);
353 hdr_sr0 = (ip6_sr_header_t *) ((u8 *) hdr_ip0 + len_bytes);
355 clib_memcpy (hdr_sr0, t0->rewrite, vec_len (t0->rewrite));
356 hdr_sr0->protocol = next_hdr;
357 hdr_ip0->protocol = ip_next_hdr;
359 /* Copy dst address into the DA slot in the segment list */
360 clib_memcpy (hdr_sr0->segments, ip0->dst_address.as_u64,
361 sizeof (ip6_address_t));
363 /* Rewrite the ip6 dst address */
364 hdr_ip0->dst_address.as_u64[0] = t0->first_hop.as_u64[0];
365 hdr_ip0->dst_address.as_u64[1] = t0->first_hop.as_u64[1];
367 sr_fix_hmac (sm, hdr_ip0, hdr_sr0);
369 /* prepend new header to invariant piece */
370 hdr_mb0->next = clone0;
371 hdr_b0->next_buffer =
372 vlib_get_buffer_index (vm,
373 vlib_buffer_from_rte_mbuf (clone0));
375 /* update header's fields */
377 (uint16_t) (hdr_mb0->data_len + clone0->pkt_len);
378 hdr_mb0->nb_segs = (uint8_t) (clone0->nb_segs + 1);
380 /* copy metadata from source packet */
381 hdr_mb0->port = clone0->port;
382 hdr_mb0->vlan_tci = clone0->vlan_tci;
383 hdr_mb0->vlan_tci_outer = clone0->vlan_tci_outer;
384 hdr_mb0->tx_offload = clone0->tx_offload;
385 hdr_mb0->hash = clone0->hash;
387 hdr_mb0->ol_flags = clone0->ol_flags & ~(IND_ATTACHED_MBUF);
389 __rte_mbuf_sanity_check (hdr_mb0, 1);
391 hdr_bi0 = vlib_get_buffer_index (vm, hdr_b0);
393 to_next[0] = hdr_bi0;
397 if (n_left_to_next == 0)
399 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
400 vlib_get_next_frame (vm, node, next_index,
401 to_next, n_left_to_next);
411 if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
413 sr_replicate_trace_t *tr = vlib_add_trace (vm, node,
415 tr->tunnel_index = t0 - sm->tunnels;
419 memcpy (tr->src.as_u8, hdr_ip0->src_address.as_u8,
420 sizeof (tr->src.as_u8));
421 memcpy (tr->dst.as_u8, hdr_ip0->dst_address.as_u8,
422 sizeof (tr->dst.as_u8));
423 if (hdr_ip0->payload_length)
424 tr->length = clib_net_to_host_u16
425 (hdr_ip0->payload_length);
427 tr->next_index = next_index;
429 memcpy (tr->sr, hdr_sr0, sizeof (tr->sr));
434 vlib_put_next_frame (vm, node, next_index, n_left_to_next);
437 vlib_node_increment_counter (vm, sr_replicate_node.index,
438 SR_REPLICATE_ERROR_REPLICATED,
441 vlib_node_increment_counter (vm, sr_replicate_node.index,
442 SR_REPLICATE_ERROR_NO_BUFFER_DROPS,
445 return frame->n_vectors;
449 VLIB_REGISTER_NODE (sr_replicate_node) = {
450 .function = sr_replicate_node_fn,
451 .name = "sr-replicate",
452 .vector_size = sizeof (u32),
453 .format_trace = format_sr_replicate_trace,
454 .type = VLIB_NODE_TYPE_INTERNAL,
456 .n_errors = ARRAY_LEN(sr_replicate_error_strings),
457 .error_strings = sr_replicate_error_strings,
459 .n_next_nodes = SR_REPLICATE_N_NEXT,
462 [SR_REPLICATE_NEXT_IP6_LOOKUP] = "ip6-lookup",
466 VLIB_NODE_FUNCTION_MULTIARCH (sr_replicate_node, sr_replicate_node_fn)
470 sr_replicate_init (vlib_main_t * vm)
472 sr_replicate_main_t *msm = &sr_replicate_main;
475 msm->vnet_main = vnet_get_main ();
480 VLIB_INIT_FUNCTION (sr_replicate_init);
485 * fd.io coding-style-patch-verification: ON
488 * eval: (c-set-style "gnu")