secchan/fail-open.c

   1 /* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
   2  * Junior University
   3  *
   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
  10  * charge, to any person obtaining a copy of this Software to deal in
  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:
  16  *
  17  * The above copyright notice and this permission notice shall be
  18  * included in all copies or substantial portions of the Software.
  19  *
  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
  27  * SOFTWARE.
  28  *
  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.
  32  */
  33
  34 #include <config.h>
  35 #include "fail-open.h"
  36 #include <arpa/inet.h>
  37 #include <stddef.h>
  38 #include <string.h>
  39 #include "learning-switch.h"
  40 #include "netdev.h"
  41 #include "packets.h"
  42 #include "port-watcher.h"
  43 #include "rconn.h"
  44 #include "secchan.h"
  45 #include "status.h"
  46 #include "stp-secchan.h"
  47 #include "timeval.h"
  48
  49 #define THIS_MODULE VLM_fail_open
  50 #include "vlog.h"
  51
  52 struct fail_open_data {
  53     const struct settings *s;
  54     struct rconn *local_rconn;
  55     struct rconn *remote_rconn;
  56     struct lswitch *lswitch;
  57     int last_disconn_secs;
  58     time_t boot_deadline;
  59 };
  60
  61 /* Causes 'r' to enter or leave fail-open mode, if appropriate. */
  62 static void
  63 fail_open_periodic_cb(void *fail_open_)
  64 {
  65     struct fail_open_data *fail_open = fail_open_;
  66     int disconn_secs;
  67     bool open;
  68
  69     if (time_now() < fail_open->boot_deadline) {
  70         return;
  71     }
  72     disconn_secs = rconn_failure_duration(fail_open->remote_rconn);
  73     open = disconn_secs >= fail_open->s->probe_interval * 3;
  74     if (open != (fail_open->lswitch != NULL)) {
  75         if (!open) {
  76             VLOG_WARN("No longer in fail-open mode");
  77             lswitch_destroy(fail_open->lswitch);
  78             fail_open->lswitch = NULL;
  79         } else {
  80             VLOG_WARN("Could not connect to controller for %d seconds, "
  81                       "failing open", disconn_secs);
  82             fail_open->lswitch = lswitch_create(fail_open->local_rconn, true,
  83                                                 fail_open->s->max_idle);
  84             fail_open->last_disconn_secs = disconn_secs;
  85         }
  86     } else if (open && disconn_secs > fail_open->last_disconn_secs + 60) {
  87         VLOG_WARN("Still in fail-open mode after %d seconds disconnected "
  88                   "from controller", disconn_secs);
  89         fail_open->last_disconn_secs = disconn_secs;
  90     }
  91     if (fail_open->lswitch) {
  92         lswitch_run(fail_open->lswitch, fail_open->local_rconn);
  93     }
  94 }
  95
  96 static void
  97 fail_open_wait_cb(void *fail_open_)
  98 {
  99     struct fail_open_data *fail_open = fail_open_;
 100     if (fail_open->lswitch) {
 101         lswitch_wait(fail_open->lswitch);
 102     }
 103 }
 104
 105 static bool
 106 fail_open_local_packet_cb(struct relay *r, void *fail_open_)
 107 {
 108     struct fail_open_data *fail_open = fail_open_;
 109     if (rconn_is_connected(fail_open->remote_rconn) || !fail_open->lswitch) {
 110         return false;
 111     } else {
 112         lswitch_process_packet(fail_open->lswitch, fail_open->local_rconn,
 113                                r->halves[HALF_LOCAL].rxbuf);
 114         rconn_run(fail_open->local_rconn);
 115         return true;
 116     }
 117 }
 118
 119 static void
 120 fail_open_status_cb(struct status_reply *sr, void *fail_open_)
 121 {
 122     struct fail_open_data *fail_open = fail_open_;
 123     const struct settings *s = fail_open->s;
 124     int trigger_duration = s->probe_interval * 3;
 125     int cur_duration = rconn_failure_duration(fail_open->remote_rconn);
 126
 127     status_reply_put(sr, "trigger-duration=%d", trigger_duration);
 128     status_reply_put(sr, "current-duration=%d", cur_duration);
 129     status_reply_put(sr, "triggered=%s",
 130                      cur_duration >= trigger_duration ? "true" : "false");
 131     status_reply_put(sr, "max-idle=%d", s->max_idle);
 132 }
 133
 134 static struct hook_class fail_open_hook_class = {
 135     fail_open_local_packet_cb,  /* local_packet_cb */
 136     NULL,                       /* remote_packet_cb */
 137     fail_open_periodic_cb,      /* periodic_cb */
 138     fail_open_wait_cb,          /* wait_cb */
 139     NULL,                       /* closing_cb */
 140 };
 141
 142 void
 143 fail_open_start(struct secchan *secchan, const struct settings *s,
 144                 struct switch_status *ss,
 145                 struct rconn *local_rconn, struct rconn *remote_rconn)
 146 {
 147     struct fail_open_data *fail_open = xmalloc(sizeof *fail_open);
 148     fail_open->s = s;
 149     fail_open->local_rconn = local_rconn;
 150     fail_open->remote_rconn = remote_rconn;
 151     fail_open->lswitch = NULL;
 152     fail_open->boot_deadline = time_now() + s->probe_interval * 3;
 153     if (s->enable_stp) {
 154         fail_open->boot_deadline += STP_EXTRA_BOOT_TIME;
 155     }
 156     switch_status_register_category(ss, "fail-open",
 157                                     fail_open_status_cb, fail_open);
 158     add_hook(secchan, &fail_open_hook_class, fail_open);
 159 }