2 * Copyright (c) 2008, 2009, 2010 Nicira Networks.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 #include "learning-switch.h"
22 #include <netinet/in.h>
26 #include "byte-order.h"
29 #include "mac-learning.h"
31 #include "ofp-parse.h"
32 #include "ofp-print.h"
34 #include "openflow/openflow.h"
35 #include "poll-loop.h"
43 VLOG_DEFINE_THIS_MODULE(learning_switch)
46 struct hmap_node hmap_node; /* Hash node for port number. */
47 uint16_t port_no; /* OpenFlow port number, in host byte order. */
48 uint32_t queue_id; /* OpenFlow queue number. */
52 /* If nonnegative, the switch sets up flows that expire after the given
53 * number of seconds (or never expire, if the value is OFP_FLOW_PERMANENT).
54 * Otherwise, the switch processes every packet. */
57 unsigned long long int datapath_id;
58 time_t last_features_request;
59 struct mac_learning *ml; /* NULL to act as hub instead of switch. */
60 uint32_t wildcards; /* Wildcards to apply to flows. */
61 bool action_normal; /* Use OFPP_NORMAL? */
63 /* Queue distribution. */
64 uint32_t default_queue; /* Default OpenFlow queue, or UINT32_MAX. */
65 struct hmap queue_numbers; /* Map from port number to lswitch_port. */
66 struct shash queue_names; /* Map from port name to lswitch_port. */
68 /* Number of outgoing queued packets on the rconn. */
69 struct rconn_packet_counter *queued;
72 /* The log messages here could actually be useful in debugging, so keep the
73 * rate limit relatively high. */
74 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30, 300);
76 static void queue_tx(struct lswitch *, struct rconn *, struct ofpbuf *);
77 static void send_features_request(struct lswitch *, struct rconn *);
79 typedef void packet_handler_func(struct lswitch *, struct rconn *, void *);
80 static packet_handler_func process_switch_features;
81 static packet_handler_func process_packet_in;
82 static packet_handler_func process_echo_request;
84 /* Creates and returns a new learning switch whose configuration is given by
87 * 'rconn' is used to send out an OpenFlow features request. */
89 lswitch_create(struct rconn *rconn, const struct lswitch_config *cfg)
91 const struct ofpbuf *b;
94 sw = xzalloc(sizeof *sw);
95 sw->max_idle = cfg->max_idle;
97 sw->last_features_request = time_now() - 1;
98 sw->ml = cfg->mode == LSW_LEARN ? mac_learning_create() : NULL;
99 sw->action_normal = cfg->mode == LSW_NORMAL;
100 if (cfg->exact_flows) {
104 /* We cannot wildcard all fields.
105 * We need in_port to detect moves.
106 * We need both SA and DA to do learning. */
107 sw->wildcards = (OFPFW_DL_TYPE | OFPFW_NW_SRC_MASK | OFPFW_NW_DST_MASK
108 | OFPFW_NW_PROTO | OFPFW_TP_SRC | OFPFW_TP_DST);
111 sw->default_queue = cfg->default_queue;
112 hmap_init(&sw->queue_numbers);
113 shash_init(&sw->queue_names);
114 if (cfg->port_queues) {
115 struct shash_node *node;
117 SHASH_FOR_EACH (node, cfg->port_queues) {
118 struct lswitch_port *port = xmalloc(sizeof *port);
119 hmap_node_nullify(&port->hmap_node);
120 port->queue_id = (uintptr_t) node->data;
121 shash_add(&sw->queue_names, node->name, port);
125 sw->queued = rconn_packet_counter_create();
126 send_features_request(sw, rconn);
128 for (b = cfg->default_flows; b; b = b->next) {
129 queue_tx(sw, rconn, ofpbuf_clone(b));
137 lswitch_destroy(struct lswitch *sw)
140 struct lswitch_port *node, *next;
142 HMAP_FOR_EACH_SAFE (node, next, hmap_node, &sw->queue_numbers) {
143 hmap_remove(&sw->queue_numbers, &node->hmap_node);
146 shash_destroy(&sw->queue_names);
147 mac_learning_destroy(sw->ml);
148 rconn_packet_counter_destroy(sw->queued);
153 /* Takes care of necessary 'sw' activity, except for receiving packets (which
154 * the caller must do). */
156 lswitch_run(struct lswitch *sw)
159 mac_learning_run(sw->ml, NULL);
164 lswitch_wait(struct lswitch *sw)
167 mac_learning_wait(sw->ml);
171 /* Processes 'msg', which should be an OpenFlow received on 'rconn', according
172 * to the learning switch state in 'sw'. The most likely result of processing
173 * is that flow-setup and packet-out OpenFlow messages will be sent out on
176 lswitch_process_packet(struct lswitch *sw, struct rconn *rconn,
177 const struct ofpbuf *msg)
182 packet_handler_func *handler;
184 static const struct processor processors[] = {
187 sizeof(struct ofp_header),
192 sizeof(struct ofp_switch_features),
193 process_switch_features
197 offsetof(struct ofp_packet_in, data),
202 sizeof(struct ofp_flow_removed),
206 const size_t n_processors = ARRAY_SIZE(processors);
207 const struct processor *p;
208 struct ofp_header *oh;
211 if (sw->datapath_id == 0
212 && oh->type != OFPT_ECHO_REQUEST
213 && oh->type != OFPT_FEATURES_REPLY) {
214 send_features_request(sw, rconn);
218 for (p = processors; p < &processors[n_processors]; p++) {
219 if (oh->type == p->type) {
220 if (msg->size < p->min_size) {
221 VLOG_WARN_RL(&rl, "%016llx: %s: too short (%zu bytes) for "
222 "type %"PRIu8" (min %zu)", sw->datapath_id,
223 rconn_get_name(rconn), msg->size, oh->type,
228 (p->handler)(sw, rconn, msg->data);
233 if (VLOG_IS_DBG_ENABLED()) {
234 char *s = ofp_to_string(msg->data, msg->size, 2);
235 VLOG_DBG_RL(&rl, "%016llx: OpenFlow packet ignored: %s",
242 send_features_request(struct lswitch *sw, struct rconn *rconn)
244 time_t now = time_now();
245 if (now >= sw->last_features_request + 1) {
247 struct ofp_switch_config *osc;
249 /* Send OFPT_FEATURES_REQUEST. */
250 make_openflow(sizeof(struct ofp_header), OFPT_FEATURES_REQUEST, &b);
251 queue_tx(sw, rconn, b);
253 /* Send OFPT_SET_CONFIG. */
254 osc = make_openflow(sizeof *osc, OFPT_SET_CONFIG, &b);
255 osc->miss_send_len = htons(OFP_DEFAULT_MISS_SEND_LEN);
256 queue_tx(sw, rconn, b);
258 sw->last_features_request = now;
263 queue_tx(struct lswitch *sw, struct rconn *rconn, struct ofpbuf *b)
265 int retval = rconn_send_with_limit(rconn, b, sw->queued, 10);
266 if (retval && retval != ENOTCONN) {
267 if (retval == EAGAIN) {
268 VLOG_INFO_RL(&rl, "%016llx: %s: tx queue overflow",
269 sw->datapath_id, rconn_get_name(rconn));
271 VLOG_WARN_RL(&rl, "%016llx: %s: send: %s",
272 sw->datapath_id, rconn_get_name(rconn),
279 process_switch_features(struct lswitch *sw, struct rconn *rconn OVS_UNUSED,
282 struct ofp_switch_features *osf = osf_;
286 if (check_ofp_message_array(&osf->header, OFPT_FEATURES_REPLY,
287 sizeof *osf, sizeof *osf->ports, &n_ports)) {
291 sw->datapath_id = ntohll(osf->datapath_id);
293 for (i = 0; i < n_ports; i++) {
294 struct ofp_phy_port *opp = &osf->ports[i];
295 struct lswitch_port *lp;
297 opp->name[OFP_MAX_PORT_NAME_LEN - 1] = '\0';
298 lp = shash_find_data(&sw->queue_names, (char *) opp->name);
299 if (lp && hmap_node_is_null(&lp->hmap_node)) {
300 lp->port_no = ntohs(opp->port_no);
301 hmap_insert(&sw->queue_numbers, &lp->hmap_node,
302 hash_int(lp->port_no, 0));
308 lswitch_choose_destination(struct lswitch *sw, const struct flow *flow)
312 /* Learn the source MAC. */
314 if (mac_learning_learn(sw->ml, flow->dl_src, 0, flow->in_port,
315 GRAT_ARP_LOCK_NONE)) {
316 VLOG_DBG_RL(&rl, "%016llx: learned that "ETH_ADDR_FMT" is on "
317 "port %"PRIu16, sw->datapath_id,
318 ETH_ADDR_ARGS(flow->dl_src), flow->in_port);
322 /* Drop frames for reserved multicast addresses. */
323 if (eth_addr_is_reserved(flow->dl_dst)) {
327 out_port = OFPP_FLOOD;
329 int learned_port = mac_learning_lookup(sw->ml, flow->dl_dst, 0, NULL);
330 if (learned_port >= 0) {
331 out_port = learned_port;
332 if (out_port == flow->in_port) {
333 /* Don't send a packet back out its input port. */
339 /* Check if we need to use "NORMAL" action. */
340 if (sw->action_normal && out_port != OFPP_FLOOD) {
348 get_queue_id(const struct lswitch *sw, uint16_t in_port)
350 const struct lswitch_port *port;
352 HMAP_FOR_EACH_WITH_HASH (port, hmap_node, hash_int(in_port, 0),
353 &sw->queue_numbers) {
354 if (port->port_no == in_port) {
355 return port->queue_id;
359 return sw->default_queue;
363 process_packet_in(struct lswitch *sw, struct rconn *rconn, void *opi_)
365 struct ofp_packet_in *opi = opi_;
366 uint16_t in_port = ntohs(opi->in_port);
370 struct ofp_action_header actions[2];
373 size_t pkt_ofs, pkt_len;
377 /* Ignore packets sent via output to OFPP_CONTROLLER. This library never
378 * uses such an action. You never know what experiments might be going on,
379 * though, and it seems best not to interfere with them. */
380 if (opi->reason != OFPR_NO_MATCH) {
384 /* Extract flow data from 'opi' into 'flow'. */
385 pkt_ofs = offsetof(struct ofp_packet_in, data);
386 pkt_len = ntohs(opi->header.length) - pkt_ofs;
387 pkt.data = opi->data;
389 flow_extract(&pkt, 0, in_port, &flow);
391 /* Choose output port. */
392 out_port = lswitch_choose_destination(sw, &flow);
395 queue_id = get_queue_id(sw, in_port);
396 if (out_port == OFPP_NONE) {
398 } else if (queue_id == UINT32_MAX || out_port >= OFPP_MAX) {
399 struct ofp_action_output oao;
401 memset(&oao, 0, sizeof oao);
402 oao.type = htons(OFPAT_OUTPUT);
403 oao.len = htons(sizeof oao);
404 oao.port = htons(out_port);
406 memcpy(actions, &oao, sizeof oao);
407 actions_len = sizeof oao;
409 struct ofp_action_enqueue oae;
411 memset(&oae, 0, sizeof oae);
412 oae.type = htons(OFPAT_ENQUEUE);
413 oae.len = htons(sizeof oae);
414 oae.port = htons(out_port);
415 oae.queue_id = htonl(queue_id);
417 memcpy(actions, &oae, sizeof oae);
418 actions_len = sizeof oae;
420 assert(actions_len <= sizeof actions);
422 /* Send the packet, and possibly the whole flow, to the output port. */
423 if (sw->max_idle >= 0 && (!sw->ml || out_port != OFPP_FLOOD)) {
424 struct ofpbuf *buffer;
425 struct ofp_flow_mod *ofm;
427 /* The output port is known, or we always flood everything, so add a
429 buffer = make_add_flow(&flow, ntohl(opi->buffer_id),
430 sw->max_idle, actions_len);
431 ofpbuf_put(buffer, actions, actions_len);
433 ofm->match.wildcards = htonl(sw->wildcards);
434 queue_tx(sw, rconn, buffer);
436 /* If the switch didn't buffer the packet, we need to send a copy. */
437 if (ntohl(opi->buffer_id) == UINT32_MAX && actions_len > 0) {
439 make_packet_out(&pkt, UINT32_MAX, in_port,
440 actions, actions_len / sizeof *actions));
443 /* We don't know that MAC, or we don't set up flows. Send along the
444 * packet without setting up a flow. */
445 if (ntohl(opi->buffer_id) != UINT32_MAX || actions_len > 0) {
447 make_packet_out(&pkt, ntohl(opi->buffer_id), in_port,
448 actions, actions_len / sizeof *actions));
454 process_echo_request(struct lswitch *sw, struct rconn *rconn, void *rq_)
456 struct ofp_header *rq = rq_;
457 queue_tx(sw, rconn, make_echo_reply(rq));