2 * Copyright (c) 2008, 2009, 2010, 2011, 2012 Nicira, Inc.
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"
27 #include "classifier.h"
30 #include "mac-learning.h"
32 #include "ofp-actions.h"
33 #include "ofp-errors.h"
34 #include "ofp-parse.h"
35 #include "ofp-print.h"
37 #include "openflow/openflow.h"
38 #include "poll-loop.h"
46 VLOG_DEFINE_THIS_MODULE(learning_switch);
49 struct hmap_node hmap_node; /* Hash node for port number. */
50 uint16_t port_no; /* OpenFlow port number, in host byte order. */
51 uint32_t queue_id; /* OpenFlow queue number. */
55 /* If nonnegative, the switch sets up flows that expire after the given
56 * number of seconds (or never expire, if the value is OFP_FLOW_PERMANENT).
57 * Otherwise, the switch processes every packet. */
60 enum ofputil_protocol protocol;
61 unsigned long long int datapath_id;
62 time_t last_features_request;
63 struct mac_learning *ml; /* NULL to act as hub instead of switch. */
64 struct flow_wildcards wc; /* Wildcards to apply to flows. */
65 bool action_normal; /* Use OFPP_NORMAL? */
67 /* Queue distribution. */
68 uint32_t default_queue; /* Default OpenFlow queue, or UINT32_MAX. */
69 struct hmap queue_numbers; /* Map from port number to lswitch_port. */
70 struct shash queue_names; /* Map from port name to lswitch_port. */
72 /* Number of outgoing queued packets on the rconn. */
73 struct rconn_packet_counter *queued;
76 /* The log messages here could actually be useful in debugging, so keep the
77 * rate limit relatively high. */
78 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(30, 300);
80 static void queue_tx(struct lswitch *, struct rconn *, struct ofpbuf *);
81 static void send_features_request(struct lswitch *, struct rconn *);
83 static enum ofperr process_switch_features(struct lswitch *,
84 struct ofp_switch_features *);
85 static void process_packet_in(struct lswitch *, struct rconn *,
86 const struct ofp_header *);
87 static void process_echo_request(struct lswitch *, struct rconn *,
88 const struct ofp_header *);
90 /* Creates and returns a new learning switch whose configuration is given by
93 * 'rconn' is used to send out an OpenFlow features request. */
95 lswitch_create(struct rconn *rconn, const struct lswitch_config *cfg)
97 enum ofputil_protocol protocol;
100 sw = xzalloc(sizeof *sw);
101 sw->max_idle = cfg->max_idle;
103 sw->last_features_request = time_now() - 1;
104 sw->ml = (cfg->mode == LSW_LEARN
105 ? mac_learning_create(MAC_ENTRY_DEFAULT_IDLE_TIME)
107 sw->action_normal = cfg->mode == LSW_NORMAL;
109 flow_wildcards_init_exact(&sw->wc);
110 if (cfg->wildcards) {
113 if (cfg->wildcards == UINT32_MAX) {
114 /* Try to wildcard as many fields as possible, but we cannot
115 * wildcard all fields. We need in_port to detect moves. We need
116 * Ethernet source and dest and VLAN VID to do L2 learning. */
117 ofpfw = (OFPFW10_DL_TYPE | OFPFW10_DL_VLAN_PCP
118 | OFPFW10_NW_SRC_ALL | OFPFW10_NW_DST_ALL
119 | OFPFW10_NW_TOS | OFPFW10_NW_PROTO
120 | OFPFW10_TP_SRC | OFPFW10_TP_DST);
122 ofpfw = cfg->wildcards;
125 ofputil_wildcard_from_ofpfw10(ofpfw, &sw->wc);
128 sw->default_queue = cfg->default_queue;
129 hmap_init(&sw->queue_numbers);
130 shash_init(&sw->queue_names);
131 if (cfg->port_queues) {
132 struct simap_node *node;
134 SIMAP_FOR_EACH (node, cfg->port_queues) {
135 struct lswitch_port *port = xmalloc(sizeof *port);
136 hmap_node_nullify(&port->hmap_node);
137 port->queue_id = node->data;
138 shash_add(&sw->queue_names, node->name, port);
142 sw->queued = rconn_packet_counter_create();
143 send_features_request(sw, rconn);
145 protocol = ofputil_protocol_from_ofp_version(rconn_get_version(rconn));
146 if (cfg->default_flows) {
147 enum ofputil_protocol usable_protocols;
148 struct ofpbuf *msg = NULL;
152 /* If the initial protocol isn't good enough for default_flows, then
153 * pick one that will work and encode messages to set up that
156 * This could be improved by actually negotiating a mutually acceptable
157 * flow format with the switch, but that would require an asynchronous
158 * state machine. This version ought to work fine in practice. */
159 usable_protocols = ofputil_flow_mod_usable_protocols(
160 cfg->default_flows, cfg->n_default_flows);
161 if (!(protocol & usable_protocols)) {
162 enum ofputil_protocol want = rightmost_1bit(usable_protocols);
164 msg = ofputil_encode_set_protocol(protocol, want, &protocol);
168 error = rconn_send(rconn, msg, NULL);
172 for (i = 0; !error && i < cfg->n_default_flows; i++) {
173 msg = ofputil_encode_flow_mod(&cfg->default_flows[i], protocol);
174 error = rconn_send(rconn, msg, NULL);
178 VLOG_INFO_RL(&rl, "%s: failed to queue default flows (%s)",
179 rconn_get_name(rconn), strerror(error));
182 sw->protocol = protocol;
189 lswitch_destroy(struct lswitch *sw)
192 struct lswitch_port *node, *next;
194 HMAP_FOR_EACH_SAFE (node, next, hmap_node, &sw->queue_numbers) {
195 hmap_remove(&sw->queue_numbers, &node->hmap_node);
198 shash_destroy(&sw->queue_names);
199 mac_learning_destroy(sw->ml);
200 rconn_packet_counter_destroy(sw->queued);
205 /* Takes care of necessary 'sw' activity, except for receiving packets (which
206 * the caller must do). */
208 lswitch_run(struct lswitch *sw)
211 mac_learning_run(sw->ml, NULL);
216 lswitch_wait(struct lswitch *sw)
219 mac_learning_wait(sw->ml);
223 /* Processes 'msg', which should be an OpenFlow received on 'rconn', according
224 * to the learning switch state in 'sw'. The most likely result of processing
225 * is that flow-setup and packet-out OpenFlow messages will be sent out on
228 lswitch_process_packet(struct lswitch *sw, struct rconn *rconn,
229 const struct ofpbuf *msg)
231 const struct ofp_header *oh = msg->data;
232 const struct ofputil_msg_type *type;
234 if (sw->datapath_id == 0
235 && oh->type != OFPT_ECHO_REQUEST
236 && oh->type != OFPT_FEATURES_REPLY) {
237 send_features_request(sw, rconn);
241 ofputil_decode_msg_type(oh, &type);
242 switch (ofputil_msg_type_code(type)) {
243 case OFPUTIL_OFPT_ECHO_REQUEST:
244 process_echo_request(sw, rconn, msg->data);
247 case OFPUTIL_OFPT_FEATURES_REPLY:
248 process_switch_features(sw, msg->data);
251 case OFPUTIL_OFPT_PACKET_IN:
252 case OFPUTIL_NXT_PACKET_IN:
253 process_packet_in(sw, rconn, msg->data);
256 case OFPUTIL_OFPT_FLOW_REMOVED:
260 case OFPUTIL_MSG_INVALID:
261 case OFPUTIL_OFPT_HELLO:
262 case OFPUTIL_OFPT_ERROR:
263 case OFPUTIL_OFPT_ECHO_REPLY:
264 case OFPUTIL_OFPT_FEATURES_REQUEST:
265 case OFPUTIL_OFPT_GET_CONFIG_REQUEST:
266 case OFPUTIL_OFPT_GET_CONFIG_REPLY:
267 case OFPUTIL_OFPT_SET_CONFIG:
268 case OFPUTIL_OFPT_PORT_STATUS:
269 case OFPUTIL_OFPT_PACKET_OUT:
270 case OFPUTIL_OFPT_FLOW_MOD:
271 case OFPUTIL_OFPT_PORT_MOD:
272 case OFPUTIL_OFPT_BARRIER_REQUEST:
273 case OFPUTIL_OFPT_BARRIER_REPLY:
274 case OFPUTIL_OFPT_QUEUE_GET_CONFIG_REQUEST:
275 case OFPUTIL_OFPT_QUEUE_GET_CONFIG_REPLY:
276 case OFPUTIL_OFPST_DESC_REQUEST:
277 case OFPUTIL_OFPST_FLOW_REQUEST:
278 case OFPUTIL_OFPST_AGGREGATE_REQUEST:
279 case OFPUTIL_OFPST_TABLE_REQUEST:
280 case OFPUTIL_OFPST_PORT_REQUEST:
281 case OFPUTIL_OFPST_QUEUE_REQUEST:
282 case OFPUTIL_OFPST_PORT_DESC_REQUEST:
283 case OFPUTIL_OFPST_DESC_REPLY:
284 case OFPUTIL_OFPST_FLOW_REPLY:
285 case OFPUTIL_OFPST_QUEUE_REPLY:
286 case OFPUTIL_OFPST_PORT_REPLY:
287 case OFPUTIL_OFPST_TABLE_REPLY:
288 case OFPUTIL_OFPST_AGGREGATE_REPLY:
289 case OFPUTIL_OFPST_PORT_DESC_REPLY:
290 case OFPUTIL_NXT_ROLE_REQUEST:
291 case OFPUTIL_NXT_ROLE_REPLY:
292 case OFPUTIL_NXT_FLOW_MOD_TABLE_ID:
293 case OFPUTIL_NXT_SET_FLOW_FORMAT:
294 case OFPUTIL_NXT_SET_PACKET_IN_FORMAT:
295 case OFPUTIL_NXT_FLOW_MOD:
296 case OFPUTIL_NXT_FLOW_REMOVED:
297 case OFPUTIL_NXT_FLOW_AGE:
298 case OFPUTIL_NXT_SET_ASYNC_CONFIG:
299 case OFPUTIL_NXT_SET_CONTROLLER_ID:
300 case OFPUTIL_NXST_FLOW_REQUEST:
301 case OFPUTIL_NXST_AGGREGATE_REQUEST:
302 case OFPUTIL_NXST_FLOW_REPLY:
303 case OFPUTIL_NXST_AGGREGATE_REPLY:
305 if (VLOG_IS_DBG_ENABLED()) {
306 char *s = ofp_to_string(msg->data, msg->size, 2);
307 VLOG_DBG_RL(&rl, "%016llx: OpenFlow packet ignored: %s",
315 send_features_request(struct lswitch *sw, struct rconn *rconn)
317 time_t now = time_now();
318 if (now >= sw->last_features_request + 1) {
320 struct ofp_switch_config *osc;
322 /* Send OFPT_FEATURES_REQUEST. */
323 make_openflow(sizeof(struct ofp_header), OFPT_FEATURES_REQUEST, &b);
324 queue_tx(sw, rconn, b);
326 /* Send OFPT_SET_CONFIG. */
327 osc = make_openflow(sizeof *osc, OFPT_SET_CONFIG, &b);
328 osc->miss_send_len = htons(OFP_DEFAULT_MISS_SEND_LEN);
329 queue_tx(sw, rconn, b);
331 sw->last_features_request = now;
336 queue_tx(struct lswitch *sw, struct rconn *rconn, struct ofpbuf *b)
338 int retval = rconn_send_with_limit(rconn, b, sw->queued, 10);
339 if (retval && retval != ENOTCONN) {
340 if (retval == EAGAIN) {
341 VLOG_INFO_RL(&rl, "%016llx: %s: tx queue overflow",
342 sw->datapath_id, rconn_get_name(rconn));
344 VLOG_WARN_RL(&rl, "%016llx: %s: send: %s",
345 sw->datapath_id, rconn_get_name(rconn),
352 process_switch_features(struct lswitch *sw, struct ofp_switch_features *osf)
354 struct ofputil_switch_features features;
355 struct ofputil_phy_port port;
359 error = ofputil_decode_switch_features(osf, &features, &b);
361 VLOG_ERR("received invalid switch feature reply (%s)",
362 ofperr_to_string(error));
366 sw->datapath_id = features.datapath_id;
368 while (!ofputil_pull_phy_port(osf->header.version, &b, &port)) {
369 struct lswitch_port *lp = shash_find_data(&sw->queue_names, port.name);
370 if (lp && hmap_node_is_null(&lp->hmap_node)) {
371 lp->port_no = port.port_no;
372 hmap_insert(&sw->queue_numbers, &lp->hmap_node,
373 hash_int(lp->port_no, 0));
380 lswitch_choose_destination(struct lswitch *sw, const struct flow *flow)
384 /* Learn the source MAC. */
385 if (mac_learning_may_learn(sw->ml, flow->dl_src, 0)) {
386 struct mac_entry *mac = mac_learning_insert(sw->ml, flow->dl_src, 0);
387 if (mac_entry_is_new(mac) || mac->port.i != flow->in_port) {
388 VLOG_DBG_RL(&rl, "%016llx: learned that "ETH_ADDR_FMT" is on "
389 "port %"PRIu16, sw->datapath_id,
390 ETH_ADDR_ARGS(flow->dl_src), flow->in_port);
392 mac->port.i = flow->in_port;
393 mac_learning_changed(sw->ml, mac);
397 /* Drop frames for reserved multicast addresses. */
398 if (eth_addr_is_reserved(flow->dl_dst)) {
402 out_port = OFPP_FLOOD;
404 struct mac_entry *mac;
406 mac = mac_learning_lookup(sw->ml, flow->dl_dst, 0, NULL);
408 out_port = mac->port.i;
409 if (out_port == flow->in_port) {
410 /* Don't send a packet back out its input port. */
416 /* Check if we need to use "NORMAL" action. */
417 if (sw->action_normal && out_port != OFPP_FLOOD) {
425 get_queue_id(const struct lswitch *sw, uint16_t in_port)
427 const struct lswitch_port *port;
429 HMAP_FOR_EACH_WITH_HASH (port, hmap_node, hash_int(in_port, 0),
430 &sw->queue_numbers) {
431 if (port->port_no == in_port) {
432 return port->queue_id;
436 return sw->default_queue;
440 process_packet_in(struct lswitch *sw, struct rconn *rconn,
441 const struct ofp_header *oh)
443 struct ofputil_packet_in pi;
447 uint64_t ofpacts_stub[64 / 8];
448 struct ofpbuf ofpacts;
450 struct ofputil_packet_out po;
456 error = ofputil_decode_packet_in(&pi, oh);
458 VLOG_WARN_RL(&rl, "failed to decode packet-in: %s",
459 ofperr_to_string(error));
463 /* Ignore packets sent via output to OFPP_CONTROLLER. This library never
464 * uses such an action. You never know what experiments might be going on,
465 * though, and it seems best not to interfere with them. */
466 if (pi.reason != OFPR_NO_MATCH) {
470 /* Extract flow data from 'opi' into 'flow'. */
471 ofpbuf_use_const(&pkt, pi.packet, pi.packet_len);
472 flow_extract(&pkt, 0, pi.fmd.tun_id, pi.fmd.in_port, &flow);
474 /* Choose output port. */
475 out_port = lswitch_choose_destination(sw, &flow);
478 queue_id = get_queue_id(sw, pi.fmd.in_port);
479 ofpbuf_use_stack(&ofpacts, ofpacts_stub, sizeof ofpacts_stub);
480 if (out_port == OFPP_NONE) {
482 } else if (queue_id == UINT32_MAX || out_port >= OFPP_MAX) {
483 ofpact_put_OUTPUT(&ofpacts)->port = out_port;
485 struct ofpact_enqueue *enqueue = ofpact_put_ENQUEUE(&ofpacts);
486 enqueue->port = out_port;
487 enqueue->queue = queue_id;
489 ofpact_pad(&ofpacts);
491 /* Prepare packet_out in case we need one. */
492 po.buffer_id = pi.buffer_id;
493 if (po.buffer_id == UINT32_MAX) {
494 po.packet = pkt.data;
495 po.packet_len = pkt.size;
500 po.in_port = pi.fmd.in_port;
501 po.ofpacts = ofpacts.data;
502 po.ofpacts_len = ofpacts.size;
504 /* Send the packet, and possibly the whole flow, to the output port. */
505 if (sw->max_idle >= 0 && (!sw->ml || out_port != OFPP_FLOOD)) {
506 struct ofputil_flow_mod fm;
507 struct ofpbuf *buffer;
509 /* The output port is known, or we always flood everything, so add a
511 memset(&fm, 0, sizeof fm);
512 cls_rule_init(&flow, &sw->wc, 0, &fm.cr);
514 fm.command = OFPFC_ADD;
515 fm.idle_timeout = sw->max_idle;
516 fm.buffer_id = pi.buffer_id;
517 fm.out_port = OFPP_NONE;
518 fm.ofpacts = ofpacts.data;
519 fm.ofpacts_len = ofpacts.size;
520 buffer = ofputil_encode_flow_mod(&fm, sw->protocol);
522 queue_tx(sw, rconn, buffer);
524 /* If the switch didn't buffer the packet, we need to send a copy. */
525 if (pi.buffer_id == UINT32_MAX && out_port != OFPP_NONE) {
526 queue_tx(sw, rconn, ofputil_encode_packet_out(&po));
529 /* We don't know that MAC, or we don't set up flows. Send along the
530 * packet without setting up a flow. */
531 if (pi.buffer_id != UINT32_MAX || out_port != OFPP_NONE) {
532 queue_tx(sw, rconn, ofputil_encode_packet_out(&po));
538 process_echo_request(struct lswitch *sw, struct rconn *rconn,
539 const struct ofp_header *rq)
541 queue_tx(sw, rconn, make_echo_reply(rq));