1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
4 * We are making the OpenFlow specification and associated documentation
5 * (Software) available for public use and benefit with the expectation
6 * that others will use, modify and enhance the Software and contribute
7 * those enhancements back to the community. However, since we would
8 * like to make the Software available for broadest use, with as few
9 * restrictions as possible permission is hereby granted, free of
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11 * the Software under the copyrights without restriction, including
12 * without limitation the rights to use, copy, modify, merge, publish,
13 * distribute, sublicense, and/or sell copies of the Software, and to
14 * permit persons to whom the Software is furnished to do so, subject to
15 * the following conditions:
17 * The above copyright notice and this permission notice shall be
18 * included in all copies or substantial portions of the Software.
20 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
23 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
24 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
25 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
26 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
29 * The name and trademarks of copyright holder(s) may NOT be used in
30 * advertising or publicity pertaining to the Software or any
31 * derivatives without specific, written prior permission.
35 #include "learning-switch.h"
39 #include <netinet/in.h>
44 #include "mac-learning.h"
46 #include "ofp-print.h"
54 #define THIS_MODULE VLM_learning_switch
58 /* If nonnegative, the switch sets up flows that expire after the given
59 * number of seconds (or never expire, if the value is OFP_FLOW_PERMANENT).
60 * Otherwise, the switch processes every packet. */
64 uint32_t capabilities;
65 time_t last_features_request;
66 struct mac_learning *ml; /* NULL to act as hub instead of switch. */
68 /* Number of outgoing queued packets on the rconn. */
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 *);
78 static void process_switch_features(struct lswitch *, struct rconn *,
79 struct ofp_switch_features *);
80 static void process_packet_in(struct lswitch *, struct rconn *,
81 struct ofp_packet_in *);
82 static void process_echo_request(struct lswitch *, struct rconn *,
84 static void process_port_status(struct lswitch *, struct rconn *,
85 struct ofp_port_status *);
86 static void process_phy_port(struct lswitch *, struct rconn *,
87 const struct ofp_phy_port *);
89 /* Creates and returns a new learning switch.
91 * If 'learn_macs' is true, the new switch will learn the ports on which MAC
92 * addresses appear. Otherwise, the new switch will flood all packets.
94 * If 'max_idle' is nonnegative, the new switch will set up flows that expire
95 * after the given number of seconds (or never expire, if 'max_idle' is
96 * OFP_FLOW_PERMANENT). Otherwise, the new switch will process every packet.
98 * 'rconn' is used to send out an OpenFlow features request. */
100 lswitch_create(struct rconn *rconn, bool learn_macs, int max_idle)
102 struct lswitch *sw = xcalloc(1, sizeof *sw);
103 sw->max_idle = max_idle;
105 sw->last_features_request = time_now() - 1;
106 sw->ml = learn_macs ? mac_learning_create() : NULL;
107 send_features_request(sw, rconn);
113 lswitch_destroy(struct lswitch *sw)
116 mac_learning_destroy(sw->ml);
122 min_size(uint8_t type)
124 return (type == OFPT_FEATURES_REPLY ? sizeof(struct ofp_switch_features)
125 : type == OFPT_PACKET_IN ? offsetof (struct ofp_packet_in, data)
126 : type == OFPT_PORT_STATUS ? sizeof(struct ofp_port_status)
127 : sizeof(struct ofp_header));
130 /* Processes 'msg', which should be an OpenFlow received on 'rconn', according
131 * to the learning switch state in 'sw'. The most likely result of processing
132 * is that flow-setup and packet-out OpenFlow messages will be sent out on
135 lswitch_process_packet(struct lswitch *sw, struct rconn *rconn,
136 const struct ofpbuf *msg)
138 struct ofp_header *oh;
141 if (msg->size < min_size(oh->type)) {
143 "%s: too short (%zu bytes) for type %"PRIu8" (min %zu)",
144 rconn_get_name(rconn),
145 msg->size, oh->type, min_size(oh->type));
149 if (oh->type == OFPT_ECHO_REQUEST) {
150 process_echo_request(sw, rconn, msg->data);
151 } else if (oh->type == OFPT_FEATURES_REPLY) {
152 process_switch_features(sw, rconn, msg->data);
153 } else if (sw->datapath_id == 0) {
154 send_features_request(sw, rconn);
155 } else if (oh->type == OFPT_PACKET_IN) {
156 process_packet_in(sw, rconn, msg->data);
157 } else if (oh->type == OFPT_PORT_STATUS) {
158 process_port_status(sw, rconn, msg->data);
160 if (VLOG_IS_DBG_ENABLED()) {
161 char *p = ofp_to_string(msg->data, msg->size, 2);
162 VLOG_DBG_RL(&rl, "OpenFlow packet ignored: %s", p);
169 send_features_request(struct lswitch *sw, struct rconn *rconn)
171 time_t now = time_now();
172 if (now >= sw->last_features_request + 1) {
174 struct ofp_switch_config *osc;
176 /* Send OFPT_FEATURES_REQUEST. */
177 make_openflow(sizeof(struct ofp_header), OFPT_FEATURES_REQUEST, &b);
178 queue_tx(sw, rconn, b);
180 /* Send OFPT_SET_CONFIG. */
181 osc = make_openflow(sizeof *osc, OFPT_SET_CONFIG, &b);
182 osc->flags = htons(OFPC_SEND_FLOW_EXP);
183 osc->miss_send_len = htons(OFP_DEFAULT_MISS_SEND_LEN);
184 queue_tx(sw, rconn, b);
186 sw->last_features_request = now;
191 queue_tx(struct lswitch *sw, struct rconn *rconn, struct ofpbuf *b)
193 int retval = rconn_send_with_limit(rconn, b, &sw->n_queued, 10);
194 if (retval && retval != ENOTCONN) {
195 if (retval == EAGAIN) {
196 VLOG_WARN_RL(&rl, "%s: tx queue overflow", rconn_get_name(rconn));
198 VLOG_WARN_RL(&rl, "%s: send: %s",
199 rconn_get_name(rconn), strerror(retval));
205 process_switch_features(struct lswitch *sw, struct rconn *rconn,
206 struct ofp_switch_features *osf)
208 size_t n_ports = ((ntohs(osf->header.length)
209 - offsetof(struct ofp_switch_features, ports))
210 / sizeof *osf->ports);
213 sw->datapath_id = osf->datapath_id;
214 sw->capabilities = ntohl(osf->capabilities);
215 for (i = 0; i < n_ports; i++) {
216 process_phy_port(sw, rconn, &osf->ports[i]);
221 process_packet_in(struct lswitch *sw, struct rconn *rconn,
222 struct ofp_packet_in *opi)
224 uint16_t in_port = ntohs(opi->in_port);
225 uint16_t out_port = OFPP_FLOOD;
227 size_t pkt_ofs, pkt_len;
231 /* Extract flow data from 'opi' into 'flow'. */
232 pkt_ofs = offsetof(struct ofp_packet_in, data);
233 pkt_len = ntohs(opi->header.length) - pkt_ofs;
234 pkt.data = opi->data;
236 flow_extract(&pkt, in_port, &flow);
239 if (mac_learning_learn(sw->ml, flow.dl_src, in_port)) {
240 VLOG_DBG_RL(&rl, "learned that "ETH_ADDR_FMT" is on datapath %"
241 PRIx64" port %"PRIu16, ETH_ADDR_ARGS(flow.dl_src),
242 ntohll(sw->datapath_id), in_port);
244 out_port = mac_learning_lookup(sw->ml, flow.dl_dst);
247 if (in_port == out_port) {
248 /* The input and output port match. Set up a flow to drop packets. */
249 queue_tx(sw, rconn, make_add_flow(&flow, ntohl(opi->buffer_id),
251 } else if (sw->max_idle >= 0 && (!sw->ml || out_port != OFPP_FLOOD)) {
252 /* The output port is known, or we always flood everything, so add a
254 queue_tx(sw, rconn, make_add_simple_flow(&flow, ntohl(opi->buffer_id),
255 out_port, sw->max_idle));
257 /* If the switch didn't buffer the packet, we need to send a copy. */
258 if (ntohl(opi->buffer_id) == UINT32_MAX) {
260 make_unbuffered_packet_out(&pkt, in_port, out_port));
263 /* We don't know that MAC, or we don't set up flows. Send along the
264 * packet without setting up a flow. */
266 if (ntohl(opi->buffer_id) == UINT32_MAX) {
267 b = make_unbuffered_packet_out(&pkt, in_port, out_port);
269 b = make_buffered_packet_out(ntohl(opi->buffer_id),
272 queue_tx(sw, rconn, b);
277 process_echo_request(struct lswitch *sw, struct rconn *rconn,
278 struct ofp_header *rq)
280 queue_tx(sw, rconn, make_echo_reply(rq));
284 process_port_status(struct lswitch *sw, struct rconn *rconn,
285 struct ofp_port_status *ops)
287 process_phy_port(sw, rconn, &ops->desc);
291 process_phy_port(struct lswitch *sw, struct rconn *rconn,
292 const struct ofp_phy_port *opp)
294 if (sw->capabilities & OFPC_STP && ntohs(opp->port_no) < OFPP_MAX) {
295 uint32_t config = ntohl(opp->config);
296 uint32_t state = ntohl(opp->state);
297 uint32_t new_config = config & ~(OFPPC_NO_RECV | OFPPC_NO_RECV_STP
298 | OFPPC_NO_FWD | OFPPC_NO_PACKET_IN);
299 if (!(config & (OFPPC_NO_STP | OFPPC_PORT_DOWN))
300 && !(state & OFPPS_LINK_DOWN)) {
301 bool forward = false;
303 switch (state & OFPPS_STP_MASK) {
304 case OFPPS_STP_LISTEN:
305 case OFPPS_STP_BLOCK:
307 case OFPPS_STP_LEARN:
310 case OFPPS_STP_FORWARD:
311 forward = learn = true;
315 new_config |= OFPPC_NO_RECV | OFPPC_NO_FWD;
318 new_config |= OFPPC_NO_PACKET_IN;
321 if (config != new_config) {
322 struct ofp_port_mod *opm;
326 VLOG_WARN("port %d: config=%x new_config=%x",
327 ntohs(opp->port_no), config, new_config);
328 opm = make_openflow(sizeof *opm, OFPT_PORT_MOD, &b);
329 opm->port_no = opp->port_no;
330 memcpy(opm->hw_addr, opp->hw_addr, OFP_ETH_ALEN);
331 opm->config = htonl(new_config);
332 opm->mask = htonl(config ^ new_config);
333 opm->advertise = htonl(0);
334 retval = rconn_send(rconn, b, NULL);
336 if (retval != ENOTCONN) {
337 VLOG_WARN_RL(&rl, "%s: send: %s",
338 rconn_get_name(rconn), strerror(retval));