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
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9 * restrictions as possible permission is hereby granted, free of
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11 * the Software under the copyrights without restriction, including
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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
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35 #include "learning-switch.h"
39 #include <netinet/in.h>
45 #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 buffer *);
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);
121 /* Processes 'msg', which should be an OpenFlow received on 'rconn', according
122 * to the learning switch state in 'sw'. The most likely result of processing
123 * is that flow-setup and packet-out OpenFlow messages will be sent out on
126 lswitch_process_packet(struct lswitch *sw, struct rconn *rconn,
127 const struct buffer *msg)
129 static const size_t min_size[UINT8_MAX + 1] = {
130 [0 ... UINT8_MAX] = sizeof (struct ofp_header),
131 [OFPT_FEATURES_REPLY] = sizeof (struct ofp_switch_features),
132 [OFPT_PACKET_IN] = offsetof (struct ofp_packet_in, data),
133 [OFPT_PORT_STATUS] = sizeof(struct ofp_port_status),
135 struct ofp_header *oh;
138 if (msg->size < min_size[oh->type]) {
140 "%s: too short (%zu bytes) for type %"PRIu8" (min %zu)",
141 rconn_get_name(rconn),
142 msg->size, oh->type, min_size[oh->type]);
146 if (oh->type == OFPT_ECHO_REQUEST) {
147 process_echo_request(sw, rconn, msg->data);
148 } else if (oh->type == OFPT_FEATURES_REPLY) {
149 process_switch_features(sw, rconn, msg->data);
150 } else if (sw->datapath_id == 0) {
151 send_features_request(sw, rconn);
152 } else if (oh->type == OFPT_PACKET_IN) {
153 process_packet_in(sw, rconn, msg->data);
154 } else if (oh->type == OFPT_PORT_STATUS) {
155 process_port_status(sw, rconn, msg->data);
157 if (VLOG_IS_DBG_ENABLED()) {
158 char *p = ofp_to_string(msg->data, msg->size, 2);
159 VLOG_DBG_RL(&rl, "OpenFlow packet ignored: %s", p);
166 send_features_request(struct lswitch *sw, struct rconn *rconn)
168 time_t now = time_now();
169 if (now >= sw->last_features_request + 1) {
171 struct ofp_switch_config *osc;
173 /* Send OFPT_FEATURES_REQUEST. */
174 make_openflow(sizeof(struct ofp_header), OFPT_FEATURES_REQUEST, &b);
175 queue_tx(sw, rconn, b);
177 /* Send OFPT_SET_CONFIG. */
178 osc = make_openflow(sizeof *osc, OFPT_SET_CONFIG, &b);
179 osc->flags = htons(OFPC_SEND_FLOW_EXP);
180 osc->miss_send_len = htons(OFP_DEFAULT_MISS_SEND_LEN);
181 queue_tx(sw, rconn, b);
183 sw->last_features_request = now;
188 queue_tx(struct lswitch *sw, struct rconn *rconn, struct buffer *b)
190 int retval = rconn_send_with_limit(rconn, b, &sw->n_queued, 10);
191 if (retval && retval != ENOTCONN) {
192 if (retval == EAGAIN) {
193 VLOG_WARN_RL(&rl, "%s: tx queue overflow", rconn_get_name(rconn));
195 VLOG_WARN_RL(&rl, "%s: send: %s",
196 rconn_get_name(rconn), strerror(retval));
202 process_switch_features(struct lswitch *sw, struct rconn *rconn,
203 struct ofp_switch_features *osf)
205 size_t n_ports = ((ntohs(osf->header.length)
206 - offsetof(struct ofp_switch_features, ports))
207 / sizeof *osf->ports);
210 sw->datapath_id = osf->datapath_id;
211 sw->capabilities = ntohl(osf->capabilities);
212 for (i = 0; i < n_ports; i++) {
213 process_phy_port(sw, rconn, &osf->ports[i]);
218 process_packet_in(struct lswitch *sw, struct rconn *rconn,
219 struct ofp_packet_in *opi)
221 uint16_t in_port = ntohs(opi->in_port);
222 uint16_t out_port = OFPP_FLOOD;
224 size_t pkt_ofs, pkt_len;
228 /* Extract flow data from 'opi' into 'flow'. */
229 pkt_ofs = offsetof(struct ofp_packet_in, data);
230 pkt_len = ntohs(opi->header.length) - pkt_ofs;
231 pkt.data = opi->data;
233 flow_extract(&pkt, in_port, &flow);
236 if (mac_learning_learn(sw->ml, flow.dl_src, in_port)) {
237 VLOG_DBG_RL(&rl, "learned that "ETH_ADDR_FMT" is on datapath %"
238 PRIx64" port %"PRIu16, ETH_ADDR_ARGS(flow.dl_src),
239 ntohll(sw->datapath_id), in_port);
241 out_port = mac_learning_lookup(sw->ml, flow.dl_dst);
244 if (in_port == out_port) {
245 /* The input and output port match. Set up a flow to drop packets. */
246 queue_tx(sw, rconn, make_add_flow(&flow, ntohl(opi->buffer_id),
248 } else if (sw->max_idle >= 0 && (!sw->ml || out_port != OFPP_FLOOD)) {
249 /* The output port is known, or we always flood everything, so add a
251 queue_tx(sw, rconn, make_add_simple_flow(&flow, ntohl(opi->buffer_id),
252 out_port, sw->max_idle));
254 /* If the switch didn't buffer the packet, we need to send a copy. */
255 if (ntohl(opi->buffer_id) == UINT32_MAX) {
257 make_unbuffered_packet_out(&pkt, in_port, out_port));
260 /* We don't know that MAC, or we don't set up flows. Send along the
261 * packet without setting up a flow. */
263 if (ntohl(opi->buffer_id) == UINT32_MAX) {
264 b = make_unbuffered_packet_out(&pkt, in_port, out_port);
266 b = make_buffered_packet_out(ntohl(opi->buffer_id),
269 queue_tx(sw, rconn, b);
274 process_echo_request(struct lswitch *sw, struct rconn *rconn,
275 struct ofp_header *rq)
277 queue_tx(sw, rconn, make_echo_reply(rq));
281 process_port_status(struct lswitch *sw, struct rconn *rconn,
282 struct ofp_port_status *ops)
284 process_phy_port(sw, rconn, &ops->desc);
288 process_phy_port(struct lswitch *sw, struct rconn *rconn,
289 const struct ofp_phy_port *opp)
291 if (sw->capabilities & OFPC_STP && opp->features & ntohl(OFPPF_STP)) {
292 uint32_t flags = ntohl(opp->flags);
293 uint32_t new_flags = flags & ~(OFPPFL_NO_RECV | OFPPFL_NO_RECV_STP
294 | OFPPFL_NO_FWD | OFPPFL_NO_PACKET_IN);
295 if (!(flags & (OFPPFL_NO_STP | OFPPFL_PORT_DOWN | OFPPFL_LINK_DOWN))) {
296 bool forward = false;
298 switch (flags & OFPPFL_STP_MASK) {
299 case OFPPFL_STP_LISTEN:
300 case OFPPFL_STP_BLOCK:
302 case OFPPFL_STP_LEARN:
305 case OFPPFL_STP_FORWARD:
306 forward = learn = true;
310 new_flags |= OFPPFL_NO_RECV | OFPPFL_NO_FWD;
313 new_flags |= OFPPFL_NO_PACKET_IN;
316 if (flags != new_flags) {
317 struct ofp_port_mod *opm;
321 VLOG_WARN("port %d: flags=%x new_flags=%x",
322 ntohs(opp->port_no), flags, new_flags);
323 opm = make_openflow(sizeof *opm, OFPT_PORT_MOD, &b);
324 opm->mask = htonl(flags ^ new_flags);
326 opm->desc.flags = htonl(new_flags);
327 retval = rconn_send(rconn, b, NULL);
329 if (retval != ENOTCONN) {
330 VLOG_WARN_RL(&rl, "%s: send: %s",
331 rconn_get_name(rconn), strerror(retval));