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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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
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29 * The name and trademarks of copyright holder(s) may NOT be used in
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34 #include "learning-switch.h"
38 #include <netinet/in.h>
44 #include "mac-learning.h"
45 #include "ofp-print.h"
52 #define THIS_MODULE VLM_learning_switch
56 bool setup_flows; /* Set up flows? (or controller processes all packets) */
58 time_t last_features_request;
59 struct mac_learning *ml; /* NULL to act as hub instead of switch. */
62 static void queue_tx(struct lswitch *, struct rconn *, struct buffer *);
63 static void send_features_request(struct lswitch *, struct rconn *);
64 static void process_packet_in(struct lswitch *, struct rconn *,
65 struct ofp_packet_in *);
67 /* Creates and returns a new learning switch.
69 * If 'learn_macs' is true, the new switch will learn the ports on which MAC
70 * addresses appear. Otherwise, the new switch will flood all packets.
72 * If 'setup_flows' is true, the new switch will set up flows. Otherwise, the
73 * new switch will process every packet.
75 * 'rconn' is used to send out an OpenFlow features request. */
77 lswitch_create(struct rconn *rconn, bool learn_macs, bool setup_flows)
79 struct lswitch *sw = xmalloc(sizeof *sw);
80 memset(sw, 0, sizeof *sw);
81 sw->setup_flows = setup_flows;
83 sw->last_features_request = 0;
84 sw->ml = learn_macs ? mac_learning_create() : NULL;
85 send_features_request(sw, rconn);
91 lswitch_destroy(struct lswitch *sw)
94 mac_learning_destroy(sw->ml);
99 /* Processes 'msg', which should be an OpenFlow received on 'rconn', according
100 * to the learning switch state in 'sw'. The most likely result of processing
101 * is that flow-setup and packet-out OpenFlow messages will be sent out on
104 lswitch_process_packet(struct lswitch *sw, struct rconn *rconn,
105 const struct buffer *msg)
107 static const size_t min_size[UINT8_MAX + 1] = {
108 [0 ... UINT8_MAX] = sizeof (struct ofp_header),
109 [OFPT_FEATURES_REPLY] = sizeof (struct ofp_switch_features),
110 [OFPT_PACKET_IN] = offsetof (struct ofp_packet_in, data),
112 struct ofp_header *oh;
115 if (msg->size < min_size[oh->type]) {
116 VLOG_WARN("%s: too short (%zu bytes) for type %"PRIu8" (min %zu)",
117 rconn_get_name(rconn),
118 msg->size, oh->type, min_size[oh->type]);
122 if (oh->type == OFPT_FEATURES_REPLY) {
123 struct ofp_switch_features *osf = msg->data;
124 sw->datapath_id = osf->datapath_id;
125 } else if (sw->datapath_id == 0) {
126 send_features_request(sw, rconn);
127 } else if (oh->type == OFPT_PACKET_IN) {
128 process_packet_in(sw, rconn, msg->data);
130 if (VLOG_IS_DBG_ENABLED()) {
131 char *p = ofp_to_string(msg->data, msg->size, 2);
132 VLOG_DBG("OpenFlow packet ignored: %s", p);
139 send_features_request(struct lswitch *sw, struct rconn *rconn)
141 time_t now = time(0);
142 if (now >= sw->last_features_request + 1) {
144 struct ofp_header *ofr;
145 struct ofp_switch_config *osc;
147 /* Send OFPT_FEATURES_REQUEST. */
149 ofr = buffer_put_uninit(b, sizeof *ofr);
150 memset(ofr, 0, sizeof *ofr);
151 ofr->type = OFPT_FEATURES_REQUEST;
152 ofr->version = OFP_VERSION;
153 ofr->length = htons(sizeof *ofr);
154 queue_tx(sw, rconn, b);
156 /* Send OFPT_SET_CONFIG. */
158 osc = buffer_put_uninit(b, sizeof *osc);
159 memset(osc, 0, sizeof *osc);
160 osc->header.type = OFPT_SET_CONFIG;
161 osc->header.version = OFP_VERSION;
162 osc->header.length = htons(sizeof *osc);
163 osc->flags = htons(OFPC_SEND_FLOW_EXP);
164 osc->miss_send_len = htons(OFP_DEFAULT_MISS_SEND_LEN);
165 queue_tx(sw, rconn, b);
167 sw->last_features_request = now;
172 queue_tx(struct lswitch *sw, struct rconn *rconn, struct buffer *b)
174 int retval = rconn_send(rconn, b);
176 if (retval == EAGAIN) {
177 /* FIXME: ratelimit. */
178 VLOG_WARN("%s: tx queue overflow", rconn_get_name(rconn));
179 } else if (retval == ENOTCONN) {
182 /* FIXME: ratelimit. */
183 VLOG_WARN("%s: send: %s", rconn_get_name(rconn), strerror(retval));
190 process_packet_in(struct lswitch *sw, struct rconn *rconn,
191 struct ofp_packet_in *opi)
193 uint16_t in_port = ntohs(opi->in_port);
194 uint16_t out_port = OFPP_FLOOD;
196 size_t pkt_ofs, pkt_len;
200 /* Extract flow data from 'opi' into 'flow'. */
201 pkt_ofs = offsetof(struct ofp_packet_in, data);
202 pkt_len = ntohs(opi->header.length) - pkt_ofs;
203 pkt.data = opi->data;
205 flow_extract(&pkt, in_port, &flow);
208 if (mac_learning_learn(sw->ml, flow.dl_src, in_port)) {
209 VLOG_DBG("learned that "ETH_ADDR_FMT" is on datapath %"
210 PRIx64" port %"PRIu16, ETH_ADDR_ARGS(flow.dl_src),
211 ntohll(sw->datapath_id), in_port);
213 out_port = mac_learning_lookup(sw->ml, flow.dl_dst);
216 if (sw->setup_flows && (!sw->ml || out_port != OFPP_FLOOD)) {
217 /* The output port is known, or we always flood everything, so add a
219 queue_tx(sw, rconn, make_add_simple_flow(&flow, ntohl(opi->buffer_id),
222 /* If the switch didn't buffer the packet, we need to send a copy. */
223 if (ntohl(opi->buffer_id) == UINT32_MAX) {
225 make_unbuffered_packet_out(&pkt, in_port, out_port));
228 /* We don't know that MAC, or we don't set up flows. Send along the
229 * packet without setting up a flow. */
231 if (ntohl(opi->buffer_id) == UINT32_MAX) {
232 b = make_unbuffered_packet_out(&pkt, in_port, out_port);
234 b = make_buffered_packet_out(ntohl(opi->buffer_id),
237 queue_tx(sw, rconn, b);