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.
19 #include <arpa/inet.h>
30 #include "openflow/openflow.h"
32 #include "poll-loop.h"
37 #define THIS_MODULE VLM_in_band
40 /* In-band control allows a single network to be used for OpenFlow
41 * traffic and other data traffic. Refer to ovs-vswitchd.conf(5) and
42 * secchan(8) for a description of configuring in-band control.
44 * This comment is an attempt to describe how in-band control works at a
45 * wire- and implementation-level. Correctly implementing in-band
46 * control has proven difficult due to its many subtleties, and has thus
47 * gone through many iterations. Please read through and understand the
48 * reasoning behind the chosen rules before making modifications.
50 * In Open vSwitch, in-band control is implemented as "hidden" flows (in that
51 * they are not visible through OpenFlow) and at a higher priority than
52 * wildcarded flows can be set up by through OpenFlow. This is done so that
53 * the OpenFlow controller cannot interfere with them and possibly break
54 * connectivity with its switches. It is possible to see all flows, including
55 * in-band ones, with the ovs-appctl "bridge/dump-flows" command.
57 * The Open vSwitch implementation of in-band control can hide traffic to
58 * arbitrary "remotes", where each remote is one TCP port on one IP address.
59 * Currently the remotes are automatically configured as the in-band OpenFlow
60 * controllers plus the OVSDB managers, if any. (The latter is a requirement
61 * because OVSDB managers are responsible for configuring OpenFlow controllers,
62 * so if the manager cannot be reached then OpenFlow cannot be reconfigured.)
64 * The following rules (with the OFPP_NORMAL action) are set up on any bridge
65 * that has any remotes:
67 * (a) DHCP requests sent from the local port.
68 * (b) ARP replies to the local port's MAC address.
69 * (c) ARP requests from the local port's MAC address.
71 * In-band also sets up the following rules for each unique next-hop MAC
72 * address for the remotes' IPs (the "next hop" is either the remote
73 * itself, if it is on a local subnet, or the gateway to reach the remote):
75 * (d) ARP replies to the next hop's MAC address.
76 * (e) ARP requests from the next hop's MAC address.
78 * In-band also sets up the following rules for each unique remote IP address:
80 * (f) ARP replies containing the remote's IP address as a target.
81 * (g) ARP requests containing the remote's IP address as a source.
83 * In-band also sets up the following rules for each unique remote (IP,port)
86 * (h) TCP traffic to the remote's IP and port.
87 * (i) TCP traffic from the remote's IP and port.
89 * The goal of these rules is to be as narrow as possible to allow a
90 * switch to join a network and be able to communicate with the
91 * remotes. As mentioned earlier, these rules have higher priority
92 * than the controller's rules, so if they are too broad, they may
93 * prevent the controller from implementing its policy. As such,
94 * in-band actively monitors some aspects of flow and packet processing
95 * so that the rules can be made more precise.
97 * In-band control monitors attempts to add flows into the datapath that
98 * could interfere with its duties. The datapath only allows exact
99 * match entries, so in-band control is able to be very precise about
100 * the flows it prevents. Flows that miss in the datapath are sent to
101 * userspace to be processed, so preventing these flows from being
102 * cached in the "fast path" does not affect correctness. The only type
103 * of flow that is currently prevented is one that would prevent DHCP
104 * replies from being seen by the local port. For example, a rule that
105 * forwarded all DHCP traffic to the controller would not be allowed,
106 * but one that forwarded to all ports (including the local port) would.
108 * As mentioned earlier, packets that miss in the datapath are sent to
109 * the userspace for processing. The userspace has its own flow table,
110 * the "classifier", so in-band checks whether any special processing
111 * is needed before the classifier is consulted. If a packet is a DHCP
112 * response to a request from the local port, the packet is forwarded to
113 * the local port, regardless of the flow table. Note that this requires
114 * L7 processing of DHCP replies to determine whether the 'chaddr' field
115 * matches the MAC address of the local port.
117 * It is interesting to note that for an L3-based in-band control
118 * mechanism, the majority of rules are devoted to ARP traffic. At first
119 * glance, some of these rules appear redundant. However, each serves an
120 * important role. First, in order to determine the MAC address of the
121 * remote side (controller or gateway) for other ARP rules, we must allow
122 * ARP traffic for our local port with rules (b) and (c). If we are
123 * between a switch and its connection to the remote, we have to
124 * allow the other switch's ARP traffic to through. This is done with
125 * rules (d) and (e), since we do not know the addresses of the other
126 * switches a priori, but do know the remote's or gateway's. Finally,
127 * if the remote is running in a local guest VM that is not reached
128 * through the local port, the switch that is connected to the VM must
129 * allow ARP traffic based on the remote's IP address, since it will
130 * not know the MAC address of the local port that is sending the traffic
131 * or the MAC address of the remote in the guest VM.
133 * With a few notable exceptions below, in-band should work in most
134 * network setups. The following are considered "supported' in the
135 * current implementation:
137 * - Locally Connected. The switch and remote are on the same
138 * subnet. This uses rules (a), (b), (c), (h), and (i).
140 * - Reached through Gateway. The switch and remote are on
141 * different subnets and must go through a gateway. This uses
142 * rules (a), (b), (c), (h), and (i).
144 * - Between Switch and Remote. This switch is between another
145 * switch and the remote, and we want to allow the other
146 * switch's traffic through. This uses rules (d), (e), (h), and
147 * (i). It uses (b) and (c) indirectly in order to know the MAC
148 * address for rules (d) and (e). Note that DHCP for the other
149 * switch will not work unless an OpenFlow controller explicitly lets this
150 * switch pass the traffic.
152 * - Between Switch and Gateway. This switch is between another
153 * switch and the gateway, and we want to allow the other switch's
154 * traffic through. This uses the same rules and logic as the
155 * "Between Switch and Remote" configuration described earlier.
157 * - Remote on Local VM. The remote is a guest VM on the
158 * system running in-band control. This uses rules (a), (b), (c),
161 * - Remote on Local VM with Different Networks. The remote
162 * is a guest VM on the system running in-band control, but the
163 * local port is not used to connect to the remote. For
164 * example, an IP address is configured on eth0 of the switch. The
165 * remote's VM is connected through eth1 of the switch, but an
166 * IP address has not been configured for that port on the switch.
167 * As such, the switch will use eth0 to connect to the remote,
168 * and eth1's rules about the local port will not work. In the
169 * example, the switch attached to eth0 would use rules (a), (b),
170 * (c), (h), and (i) on eth0. The switch attached to eth1 would use
171 * rules (f), (g), (h), and (i).
173 * The following are explicitly *not* supported by in-band control:
175 * - Specify Remote by Name. Currently, the remote must be
176 * identified by IP address. A naive approach would be to permit
177 * all DNS traffic. Unfortunately, this would prevent the
178 * controller from defining any policy over DNS. Since switches
179 * that are located behind us need to connect to the remote,
180 * in-band cannot simply add a rule that allows DNS traffic from
181 * the local port. The "correct" way to support this is to parse
182 * DNS requests to allow all traffic related to a request for the
183 * remote's name through. Due to the potential security
184 * problems and amount of processing, we decided to hold off for
187 * - Differing Remotes for Switches. All switches must know
188 * the L3 addresses for all the remotes that other switches
189 * may use, since rules need to be set up to allow traffic related
190 * to those remotes through. See rules (f), (g), (h), and (i).
192 * - Differing Routes for Switches. In order for the switch to
193 * allow other switches to connect to a remote through a
194 * gateway, it allows the gateway's traffic through with rules (d)
195 * and (e). If the routes to the remote differ for the two
196 * switches, we will not know the MAC address of the alternate
200 /* Priorities used in classifier for in-band rules. These values are higher
201 * than any that may be set with OpenFlow, and "18" kind of looks like "IB".
202 * The ordering of priorities is not important because all of the rules set up
203 * by in-band control have the same action. The only reason to use more than
204 * one priority is to make the kind of flow easier to see during debugging. */
206 /* One set per bridge. */
207 IBR_FROM_LOCAL_DHCP = 180000, /* (a) From local port, DHCP. */
208 IBR_TO_LOCAL_ARP, /* (b) To local port, ARP. */
209 IBR_FROM_LOCAL_ARP, /* (c) From local port, ARP. */
211 /* One set per unique next-hop MAC. */
212 IBR_TO_NEXT_HOP_ARP, /* (d) To remote MAC, ARP. */
213 IBR_FROM_NEXT_HOP_ARP, /* (e) From remote MAC, ARP. */
215 /* One set per unique remote IP address. */
216 IBR_TO_REMOTE_ARP, /* (f) To remote IP, ARP. */
217 IBR_FROM_REMOTE_ARP, /* (g) From remote IP, ARP. */
219 /* One set per unique remote (IP,port) pair. */
220 IBR_TO_REMOTE_TCP, /* (h) To remote IP, TCP port. */
221 IBR_FROM_REMOTE_TCP /* (i) From remote IP, TCP port. */
224 struct in_band_rule {
228 /* Track one remote IP and next hop information. */
229 struct in_band_remote {
230 struct sockaddr_in remote_addr; /* IP address, in network byte order. */
231 uint8_t remote_mac[ETH_ADDR_LEN]; /* Next-hop MAC, all-zeros if unknown. */
232 uint8_t last_remote_mac[ETH_ADDR_LEN]; /* Previous nonzero next-hop MAC. */
233 struct netdev *remote_netdev; /* Device to send to next-hop MAC. */
237 struct ofproto *ofproto;
238 struct status_category *ss_cat;
240 /* Remote information. */
241 time_t next_remote_refresh; /* Refresh timer. */
242 struct in_band_remote *remotes;
245 /* Local information. */
246 time_t next_local_refresh; /* Refresh timer. */
247 uint8_t local_mac[ETH_ADDR_LEN]; /* Current MAC. */
248 struct netdev *local_netdev; /* Local port's network device. */
250 /* Local and remote addresses that are installed as flows. */
251 uint8_t installed_local_mac[ETH_ADDR_LEN];
252 struct sockaddr_in *remote_addrs;
253 size_t n_remote_addrs;
254 uint8_t *remote_macs;
255 size_t n_remote_macs;
258 static struct vlog_rate_limit rl = VLOG_RATE_LIMIT_INIT(60, 60);
261 refresh_remote(struct in_band *ib, struct in_band_remote *r)
263 struct in_addr next_hop_inaddr;
267 /* Find the next-hop IP address. */
268 memset(r->remote_mac, 0, sizeof r->remote_mac);
269 retval = netdev_get_next_hop(ib->local_netdev, &r->remote_addr.sin_addr,
270 &next_hop_inaddr, &next_hop_dev);
272 VLOG_WARN("cannot find route for controller ("IP_FMT"): %s",
273 IP_ARGS(&r->remote_addr.sin_addr), strerror(retval));
276 if (!next_hop_inaddr.s_addr) {
277 next_hop_inaddr = r->remote_addr.sin_addr;
280 /* Open the next-hop network device. */
281 if (!r->remote_netdev
282 || strcmp(netdev_get_name(r->remote_netdev), next_hop_dev))
284 netdev_close(r->remote_netdev);
286 retval = netdev_open_default(next_hop_dev, &r->remote_netdev);
288 VLOG_WARN_RL(&rl, "cannot open netdev %s (next hop "
289 "to controller "IP_FMT"): %s",
290 next_hop_dev, IP_ARGS(&r->remote_addr.sin_addr),
298 /* Look up the MAC address of the next-hop IP address. */
299 retval = netdev_arp_lookup(r->remote_netdev, next_hop_inaddr.s_addr,
302 VLOG_DBG_RL(&rl, "cannot look up remote MAC address ("IP_FMT"): %s",
303 IP_ARGS(&next_hop_inaddr.s_addr), strerror(retval));
306 /* If we don't have a MAC address, then refresh quickly, since we probably
307 * will get a MAC address soon (via ARP). Otherwise, we can afford to wait
309 return eth_addr_is_zero(r->remote_mac) ? 1 : 10;
313 refresh_remotes(struct in_band *ib)
315 struct in_band_remote *r;
318 if (time_now() < ib->next_remote_refresh) {
323 ib->next_remote_refresh = TIME_MAX;
324 for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
325 uint8_t old_remote_mac[ETH_ADDR_LEN];
329 memcpy(old_remote_mac, r->remote_mac, ETH_ADDR_LEN);
331 /* Refresh remote information. */
332 next_refresh = refresh_remote(ib, r) + time_now();
333 ib->next_remote_refresh = MIN(ib->next_remote_refresh, next_refresh);
335 /* If the MAC changed, log the changes. */
336 if (!eth_addr_equals(r->remote_mac, old_remote_mac)) {
338 if (!eth_addr_is_zero(r->remote_mac)
339 && !eth_addr_equals(r->last_remote_mac, r->remote_mac)) {
340 VLOG_DBG("remote MAC address changed from "ETH_ADDR_FMT
342 ETH_ADDR_ARGS(r->last_remote_mac),
343 ETH_ADDR_ARGS(r->remote_mac));
344 memcpy(r->last_remote_mac, r->remote_mac, ETH_ADDR_LEN);
352 /* Refreshes the MAC address of the local port into ib->local_mac, if it is due
353 * for a refresh. Returns true if anything changed, otherwise false. */
355 refresh_local(struct in_band *ib)
357 uint8_t ea[ETH_ADDR_LEN];
361 if (now < ib->next_local_refresh) {
364 ib->next_local_refresh = now + 1;
366 if (netdev_get_etheraddr(ib->local_netdev, ea)
367 || eth_addr_equals(ea, ib->local_mac)) {
371 memcpy(ib->local_mac, ea, ETH_ADDR_LEN);
376 in_band_status_cb(struct status_reply *sr, void *in_band_)
378 struct in_band *in_band = in_band_;
380 if (!eth_addr_is_zero(in_band->local_mac)) {
381 status_reply_put(sr, "local-mac="ETH_ADDR_FMT,
382 ETH_ADDR_ARGS(in_band->local_mac));
385 if (in_band->n_remotes
386 && !eth_addr_is_zero(in_band->remotes[0].remote_mac)) {
387 status_reply_put(sr, "remote-mac="ETH_ADDR_FMT,
388 ETH_ADDR_ARGS(in_band->remotes[0].remote_mac));
393 init_rule(struct in_band_rule *rule, unsigned int priority)
395 /* Clearing the flow is not strictly necessary but it seems cleaner. */
396 memset(&rule->flow, 0, sizeof rule->flow);
398 rule->flow.wildcards = OVSFW_ALL;
399 rule->flow.priority = priority;
403 set_in_port(struct in_band_rule *rule, uint16_t ofp_port)
405 rule->flow.wildcards &= ~OFPFW_IN_PORT;
406 rule->flow.in_port = ofp_port;
410 set_dl_type(struct in_band_rule *rule, uint16_t dl_type)
412 rule->flow.wildcards &= ~OFPFW_DL_TYPE;
413 rule->flow.dl_type = dl_type;
417 set_dl_src(struct in_band_rule *rule, const uint8_t dl_src[ETH_ADDR_LEN])
419 rule->flow.wildcards &= ~OFPFW_DL_SRC;
420 memcpy(rule->flow.dl_src, dl_src, ETH_ADDR_LEN);
424 set_dl_dst(struct in_band_rule *rule, const uint8_t dl_dst[ETH_ADDR_LEN])
426 rule->flow.wildcards &= ~OFPFW_DL_DST;
427 memcpy(rule->flow.dl_dst, dl_dst, ETH_ADDR_LEN);
431 set_tp_src(struct in_band_rule *rule, uint16_t tp_src)
433 rule->flow.wildcards &= ~OFPFW_TP_SRC;
434 rule->flow.tp_src = tp_src;
438 set_tp_dst(struct in_band_rule *rule, uint16_t tp_dst)
440 rule->flow.wildcards &= ~OFPFW_TP_DST;
441 rule->flow.tp_dst = tp_dst;
445 set_nw_proto(struct in_band_rule *rule, uint8_t nw_proto)
447 rule->flow.wildcards &= ~OFPFW_NW_PROTO;
448 rule->flow.nw_proto = nw_proto;
452 set_nw_src(struct in_band_rule *rule, const struct in_addr nw_src)
454 rule->flow.wildcards &= ~OFPFW_NW_SRC_MASK;
455 rule->flow.nw_src = nw_src.s_addr;
459 set_nw_dst(struct in_band_rule *rule, const struct in_addr nw_dst)
461 rule->flow.wildcards &= ~OFPFW_NW_DST_MASK;
462 rule->flow.nw_dst = nw_dst.s_addr;
466 make_rules(struct in_band *ib,
467 void (*cb)(struct in_band *, const struct in_band_rule *))
469 struct in_band_rule rule;
472 if (!eth_addr_is_zero(ib->installed_local_mac)) {
473 /* (a) Allow DHCP requests sent from the local port. */
474 init_rule(&rule, IBR_FROM_LOCAL_DHCP);
475 set_in_port(&rule, OFPP_LOCAL);
476 set_dl_type(&rule, htons(ETH_TYPE_IP));
477 set_dl_src(&rule, ib->installed_local_mac);
478 set_nw_proto(&rule, IP_TYPE_UDP);
479 set_tp_src(&rule, htons(DHCP_CLIENT_PORT));
480 set_tp_dst(&rule, htons(DHCP_SERVER_PORT));
483 /* (b) Allow ARP replies to the local port's MAC address. */
484 init_rule(&rule, IBR_TO_LOCAL_ARP);
485 set_dl_type(&rule, htons(ETH_TYPE_ARP));
486 set_dl_dst(&rule, ib->installed_local_mac);
487 set_nw_proto(&rule, ARP_OP_REPLY);
490 /* (c) Allow ARP requests from the local port's MAC address. */
491 init_rule(&rule, IBR_FROM_LOCAL_ARP);
492 set_dl_type(&rule, htons(ETH_TYPE_ARP));
493 set_dl_src(&rule, ib->installed_local_mac);
494 set_nw_proto(&rule, ARP_OP_REQUEST);
498 for (i = 0; i < ib->n_remote_macs; i++) {
499 const uint8_t *remote_mac = &ib->remote_macs[i * ETH_ADDR_LEN];
502 const uint8_t *prev_mac = &ib->remote_macs[(i - 1) * ETH_ADDR_LEN];
503 if (eth_addr_equals(remote_mac, prev_mac)) {
504 /* Skip duplicates. */
509 /* (d) Allow ARP replies to the next hop's MAC address. */
510 init_rule(&rule, IBR_TO_NEXT_HOP_ARP);
511 set_dl_type(&rule, htons(ETH_TYPE_ARP));
512 set_dl_dst(&rule, remote_mac);
513 set_nw_proto(&rule, ARP_OP_REPLY);
516 /* (e) Allow ARP requests from the next hop's MAC address. */
517 init_rule(&rule, IBR_FROM_NEXT_HOP_ARP);
518 set_dl_type(&rule, htons(ETH_TYPE_ARP));
519 set_dl_src(&rule, remote_mac);
520 set_nw_proto(&rule, ARP_OP_REQUEST);
524 for (i = 0; i < ib->n_remote_addrs; i++) {
525 const struct sockaddr_in *a = &ib->remote_addrs[i];
527 if (!i || a->sin_addr.s_addr != a[-1].sin_addr.s_addr) {
528 /* (f) Allow ARP replies containing the remote's IP address as a
530 init_rule(&rule, IBR_TO_REMOTE_ARP);
531 set_dl_type(&rule, htons(ETH_TYPE_ARP));
532 set_nw_proto(&rule, ARP_OP_REPLY);
533 set_nw_dst(&rule, a->sin_addr);
536 /* (g) Allow ARP requests containing the remote's IP address as a
538 init_rule(&rule, IBR_FROM_REMOTE_ARP);
539 set_dl_type(&rule, htons(ETH_TYPE_ARP));
540 set_nw_proto(&rule, ARP_OP_REQUEST);
541 set_nw_src(&rule, a->sin_addr);
546 || a->sin_addr.s_addr != a[-1].sin_addr.s_addr
547 || a->sin_port != a[-1].sin_port) {
548 /* (h) Allow TCP traffic to the remote's IP and port. */
549 init_rule(&rule, IBR_TO_REMOTE_TCP);
550 set_dl_type(&rule, htons(ETH_TYPE_IP));
551 set_nw_proto(&rule, IP_TYPE_TCP);
552 set_nw_dst(&rule, a->sin_addr);
553 set_tp_dst(&rule, a->sin_port);
556 /* (i) Allow TCP traffic from the remote's IP and port. */
557 init_rule(&rule, IBR_FROM_REMOTE_TCP);
558 set_dl_type(&rule, htons(ETH_TYPE_IP));
559 set_nw_proto(&rule, IP_TYPE_TCP);
560 set_nw_src(&rule, a->sin_addr);
561 set_tp_src(&rule, a->sin_port);
568 drop_rule(struct in_band *ib, const struct in_band_rule *rule)
570 ofproto_delete_flow(ib->ofproto, &rule->flow);
573 /* Drops from the flow table all of the flows set up by 'ib', then clears out
574 * the information about the installed flows so that they can be filled in
575 * again if necessary. */
577 drop_rules(struct in_band *ib)
580 make_rules(ib, drop_rule);
582 /* Clear out state. */
583 memset(ib->installed_local_mac, 0, sizeof ib->installed_local_mac);
585 free(ib->remote_addrs);
586 ib->remote_addrs = NULL;
587 ib->n_remote_addrs = 0;
589 free(ib->remote_macs);
590 ib->remote_macs = NULL;
591 ib->n_remote_macs = 0;
595 add_rule(struct in_band *ib, const struct in_band_rule *rule)
597 union ofp_action action;
599 action.type = htons(OFPAT_OUTPUT);
600 action.output.len = htons(sizeof action);
601 action.output.port = htons(OFPP_NORMAL);
602 action.output.max_len = htons(0);
603 ofproto_add_flow(ib->ofproto, &rule->flow, &action, 1, 0);
606 /* Inserts flows into the flow table for the current state of 'ib'. */
608 add_rules(struct in_band *ib)
610 make_rules(ib, add_rule);
614 compare_addrs(const void *a_, const void *b_)
616 const struct sockaddr_in *a = a_;
617 const struct sockaddr_in *b = b_;
620 cmp = memcmp(&a->sin_addr.s_addr,
622 sizeof a->sin_addr.s_addr);
626 return memcmp(&a->sin_port, &b->sin_port, sizeof a->sin_port);
630 compare_macs(const void *a, const void *b)
632 return memcmp(a, b, ETH_ADDR_LEN);
636 in_band_run(struct in_band *ib)
638 struct in_band_remote *r;
639 bool local_change, remote_change;
641 local_change = refresh_local(ib);
642 remote_change = refresh_remotes(ib);
643 if (!local_change && !remote_change) {
644 /* Nothing changed, nothing to do. */
648 /* Drop old rules. */
651 /* Figure out new rules. */
652 memcpy(ib->installed_local_mac, ib->local_mac, ETH_ADDR_LEN);
653 ib->remote_addrs = xmalloc(ib->n_remotes * sizeof *ib->remote_addrs);
654 ib->n_remote_addrs = 0;
655 ib->remote_macs = xmalloc(ib->n_remotes * ETH_ADDR_LEN);
656 ib->n_remote_macs = 0;
657 for (r = ib->remotes; r < &ib->remotes[ib->n_remotes]; r++) {
658 ib->remote_addrs[ib->n_remote_addrs++] = r->remote_addr;
659 if (!eth_addr_is_zero(r->remote_mac)) {
660 memcpy(&ib->remote_macs[ib->n_remote_macs * ETH_ADDR_LEN],
661 r->remote_mac, ETH_ADDR_LEN);
666 /* Sort, to allow make_rules() to easily skip duplicates. */
667 qsort(ib->remote_addrs, ib->n_remote_addrs, sizeof *ib->remote_addrs,
669 qsort(ib->remote_macs, ib->n_remote_macs, ETH_ADDR_LEN, compare_macs);
676 in_band_wait(struct in_band *in_band)
678 time_t now = time_now();
680 = MIN(in_band->next_remote_refresh, in_band->next_local_refresh);
682 poll_timer_wait((wakeup - now) * 1000);
684 poll_immediate_wake();
688 /* ofproto has flushed all flows from the flow table and it is calling us back
689 * to allow us to reinstall the ones that are important to us. */
691 in_band_flushed(struct in_band *in_band)
697 in_band_create(struct ofproto *ofproto, struct wdp *wdp,
698 struct switch_status *ss, struct in_band **in_bandp)
700 struct in_band *in_band;
701 struct netdev *local_netdev;
705 error = wdp_port_get_name(wdp, OFPP_LOCAL, &local_name);
707 VLOG_ERR("failed to initialize in-band control: cannot get name "
708 "of datapath local port (%s)", strerror(error));
712 error = netdev_open_default(local_name, &local_netdev);
714 VLOG_ERR("failed to initialize in-band control: cannot open "
715 "datapath local port %s (%s)", local_name, strerror(error));
721 in_band = xzalloc(sizeof *in_band);
722 in_band->ofproto = ofproto;
723 in_band->ss_cat = switch_status_register(ss, "in-band",
724 in_band_status_cb, in_band);
725 in_band->next_remote_refresh = TIME_MIN;
726 in_band->next_local_refresh = TIME_MIN;
727 in_band->local_netdev = local_netdev;
735 in_band_destroy(struct in_band *ib)
739 in_band_set_remotes(ib, NULL, 0);
740 switch_status_unregister(ib->ss_cat);
741 netdev_close(ib->local_netdev);
747 any_addresses_changed(struct in_band *ib,
748 const struct sockaddr_in *addresses, size_t n)
752 if (n != ib->n_remotes) {
756 for (i = 0; i < n; i++) {
757 const struct sockaddr_in *old = &ib->remotes[i].remote_addr;
758 const struct sockaddr_in *new = &addresses[i];
760 if (old->sin_addr.s_addr != new->sin_addr.s_addr ||
761 old->sin_port != new->sin_port) {
770 in_band_set_remotes(struct in_band *ib,
771 const struct sockaddr_in *addresses, size_t n)
775 if (!any_addresses_changed(ib, addresses, n)) {
779 /* Clear old remotes. */
780 for (i = 0; i < ib->n_remotes; i++) {
781 netdev_close(ib->remotes[i].remote_netdev);
785 /* Set up new remotes. */
786 ib->remotes = n ? xzalloc(n * sizeof *ib->remotes) : NULL;
788 for (i = 0; i < n; i++) {
789 ib->remotes[i].remote_addr = addresses[i];
792 /* Force refresh in next call to in_band_run(). */
793 ib->next_remote_refresh = TIME_MIN;