isisd: add support for draft-ietf-rtgwg-backoff-algo

Adds CLI command "spf-delay-ietf" to area node for configuration
and "show isis spf-delay-ietf" to enable node for displaying status.

4 files changed, 161 insertions, 0 deletions

diff --git a/isisd/isis_spf.c b/isisd/isis_spf.c
index 6efc1fc4d..db46078f2 100644
--- a/isisd/isis_spf.c
+++ b/isisd/isis_spf.c
@@ -33,6 +33,7 @@
 #include "hash.h"
 #include "if.h"
 #include "table.h"
+#include "spf_backoff.h"
 
 #include "isis_constants.h"
 #include "isis_common.h"
@@ -1318,6 +1319,27 @@ isis_spf_schedule (struct isis_area *area, int level)
     zlog_debug ("ISIS-Spf (%s) L%d SPF schedule called, lastrun %d sec ago",
                 area->area_tag, level, diff);
 
+  if (area->spf_delay_ietf[level - 1])
+    {
+      /* Need to call schedule function also if spf delay is running to
+       * restart holdoff timer - compare draft-ietf-rtgwg-backoff-algo-04 */
+      long delay = spf_backoff_schedule(area->spf_delay_ietf[level -1]);
+      if (area->spf_timer[level - 1])
+        return ISIS_OK;
+
+      if (level == 1)
+        {
+          THREAD_TIMER_MSEC_ON(master, area->spf_timer[0],
+                               isis_run_spf_l1, area, delay);
+        }
+      else
+        {
+          THREAD_TIMER_MSEC_ON(master, area->spf_timer[1],
+                               isis_run_spf_l2, area, delay);
+        }
+      return ISIS_OK;
+    }
+
   if (area->spf_timer[level -1])
     return ISIS_OK;
 
diff --git a/isisd/isis_vty.c b/isisd/isis_vty.c
index a73598bac..721959859 100644
--- a/isisd/isis_vty.c
+++ b/isisd/isis_vty.c
@@ -24,6 +24,7 @@
 #include <zebra.h>
 
 #include "command.h"
+#include "spf_backoff.h"
 
 #include "isis_circuit.h"
 #include "isis_csm.h"
@@ -1708,6 +1709,63 @@ DEFUN (no_spf_interval_l2,
   return CMD_SUCCESS;
 }
 
+DEFUN (no_spf_delay_ietf,
+       no_spf_delay_ietf_cmd,
+       "no spf-delay-ietf",
+       NO_STR
+       "IETF SPF delay algorithm\n")
+{
+  VTY_DECLVAR_CONTEXT (isis_area, area);
+
+  spf_backoff_free(area->spf_delay_ietf[0]);
+  spf_backoff_free(area->spf_delay_ietf[1]);
+  area->spf_delay_ietf[0] = NULL;
+  area->spf_delay_ietf[1] = NULL;
+
+  return CMD_SUCCESS;
+}
+
+DEFUN (spf_delay_ietf,
+       spf_delay_ietf_cmd,
+       "spf-delay-ietf init-delay (0-60000) short-delay (0-60000) long-delay (0-60000) holddown (0-60000) time-to-learn (0-60000)",
+       "IETF SPF delay algorithm\n"
+       "Delay used while in QUIET state\n"
+       "Delay used while in QUIET state in milliseconds\n"
+       "Delay used while in SHORT_WAIT state\n"
+       "Delay used while in SHORT_WAIT state in milliseconds\n"
+       "Delay used while in LONG_WAIT\n"
+       "Delay used while in LONG_WAIT state in milliseconds\n"
+       "Time with no received IGP events before considering IGP stable\n"
+       "Time with no received IGP events before considering IGP stable (in milliseconds)\n"
+       "Maximum duration needed to learn all the events related to a single failure\n"
+       "Maximum duration needed to learn all the events related to a single failure (in milliseconds)\n")
+{
+  VTY_DECLVAR_CONTEXT (isis_area, area);
+
+  long init_delay = atol(argv[2]->arg);
+  long short_delay = atol(argv[4]->arg);
+  long long_delay = atol(argv[6]->arg);
+  long holddown = atol(argv[8]->arg);
+  long timetolearn = atol(argv[10]->arg);
+
+  size_t bufsiz = strlen(area->area_tag) + sizeof("IS-IS  Lx");
+  char *buf = XCALLOC(MTYPE_TMP, bufsiz);
+
+  snprintf(buf, bufsiz, "IS-IS %s L1", area->area_tag);
+  spf_backoff_free(area->spf_delay_ietf[0]);
+  area->spf_delay_ietf[0] = spf_backoff_new(master, buf, init_delay,
+                                            short_delay, long_delay,
+                                            holddown, timetolearn);
+
+  snprintf(buf, bufsiz, "IS-IS %s L2", area->area_tag);
+  spf_backoff_free(area->spf_delay_ietf[1]);
+  area->spf_delay_ietf[1] = spf_backoff_new(master, buf, init_delay,
+                                            short_delay, long_delay,
+                                            holddown, timetolearn);
+
+  XFREE(MTYPE_TMP, buf);
+  return CMD_SUCCESS;
+}
 
 static int
 area_max_lsp_lifetime_set(struct vty *vty, int level,
@@ -2097,4 +2155,8 @@ isis_vty_init (void)
   install_element (ISIS_NODE, &domain_passwd_md5_cmd);
   install_element (ISIS_NODE, &domain_passwd_clear_cmd);
   install_element (ISIS_NODE, &no_area_passwd_cmd);
+
+  install_element (ISIS_NODE, &spf_delay_ietf_cmd);
+  install_element (ISIS_NODE, &no_spf_delay_ietf_cmd);
+
 }
diff --git a/isisd/isisd.c b/isisd/isisd.c
index 4d94f243d..2863d2f67 100644
--- a/isisd/isisd.c
+++ b/isisd/isisd.c
@@ -35,6 +35,7 @@
 #include "prefix.h"
 #include "table.h"
 #include "qobj.h"
+#include "spf_backoff.h"
 
 #include "isisd/dict.h"
 #include "isisd/isis_constants.h"
@@ -248,6 +249,9 @@ isis_area_destroy (struct vty *vty, const char *area_tag)
   THREAD_TIMER_OFF(area->spf_timer[0]);
   THREAD_TIMER_OFF(area->spf_timer[1]);
 
+  spf_backoff_free(area->spf_delay_ietf[0]);
+  spf_backoff_free(area->spf_delay_ietf[1]);
+
   /* invalidate and validate would delete all routes from zebra */
   isis_route_invalidate (area);
   isis_route_validate (area);
@@ -859,6 +863,7 @@ config_write_debug (struct vty *vty)
       vty_out (vty, "debug isis lsp-sched%s", VTY_NEWLINE);
       write++;
     }
+  write += spf_backoff_write_config(vty);
 
   return write;
 }
@@ -1276,6 +1281,57 @@ vty_out_timestr(struct vty *vty, time_t uptime)
   vty_out (vty, " ago");
 }
 
+DEFUN (show_isis_spf_ietf,
+       show_isis_spf_ietf_cmd,
+       "show isis spf-delay-ietf",
+       SHOW_STR
+       "IS-IS information\n"
+       "IS-IS SPF delay IETF information\n")
+{
+  if (!isis)
+    {
+      vty_out (vty, "ISIS is not running%s", VTY_NEWLINE);
+      return CMD_SUCCESS;
+    }
+
+  struct listnode *node;
+  struct isis_area *area;
+
+  for (ALL_LIST_ELEMENTS_RO (isis->area_list, node, area))
+    {
+      vty_out (vty, "Area %s:%s", area->area_tag ? area->area_tag : "null",
+               VTY_NEWLINE);
+
+      for (int level = ISIS_LEVEL1; level <= ISIS_LEVELS; level++)
+        {
+          if ((area->is_type & level) == 0)
+            continue;
+
+          vty_out (vty, "  Level-%d:%s", level, VTY_NEWLINE);
+          vty_out (vty, "    SPF delay status: ");
+          if (area->spf_timer[level -1])
+            {
+              struct timeval remain = thread_timer_remain(area->spf_timer[level - 1]);
+              vty_out(vty, "Pending, due in %ld msec%s",
+                      remain.tv_sec * 1000 + remain.tv_usec / 1000,
+                      VTY_NEWLINE);
+            }
+          else
+            {
+              vty_out(vty, "Not scheduled%s", VTY_NEWLINE);
+            }
+
+          if (area->spf_delay_ietf[level - 1]) {
+            vty_out(vty,  "    Using draft-ietf-rtgwg-backoff-algo-04%s", VTY_NEWLINE);
+            spf_backoff_show(area->spf_delay_ietf[level - 1], vty, "    ");
+          } else {
+            vty_out(vty,  "    Using legacy backoff algo%s", VTY_NEWLINE);
+          }
+        }
+    }
+  return CMD_SUCCESS;
+}
+
 DEFUN (show_isis_summary,
        show_isis_summary_cmd,
        "show isis summary",
@@ -1337,6 +1393,8 @@ DEFUN (show_isis_summary,
 
       vty_out (vty, "      minimum interval  : %d",
           area->min_spf_interval[level - 1]);
+      if (area->spf_delay_ietf[level - 1])
+         vty_out (vty, " (not used, IETF SPF delay activated)");
       vty_out (vty, VTY_NEWLINE);
 
       vty_out (vty, "    IPv4 route computation:%s", VTY_NEWLINE);
@@ -2010,6 +2068,20 @@ isis_config_write (struct vty *vty)
 		write++;
 	      }
 	  }
+
+	/* IETF SPF interval */
+	if (area->spf_delay_ietf[0])
+	  {
+	    vty_out (vty, " spf-delay-ietf init-delay %ld short-delay %ld long-delay %ld holddown %ld time-to-learn %ld%s",
+	             spf_backoff_init_delay(area->spf_delay_ietf[0]),
+	             spf_backoff_short_delay(area->spf_delay_ietf[0]),
+	             spf_backoff_long_delay(area->spf_delay_ietf[0]),
+	             spf_backoff_holddown(area->spf_delay_ietf[0]),
+	             spf_backoff_timetolearn(area->spf_delay_ietf[0]),
+	             VTY_NEWLINE);
+	    write++;
+	  }
+
 	/* Authentication passwords. */
 	if (area->area_passwd.type == ISIS_PASSWD_TYPE_HMAC_MD5)
 	  {
@@ -2097,6 +2169,8 @@ isis_init ()
 
   install_element (VIEW_NODE, &show_isis_summary_cmd);
 
+  install_element (VIEW_NODE, &show_isis_spf_ietf_cmd);
+
   install_element (VIEW_NODE, &show_isis_interface_cmd);
   install_element (VIEW_NODE, &show_isis_interface_detail_cmd);
   install_element (VIEW_NODE, &show_isis_interface_arg_cmd);
@@ -2182,4 +2256,6 @@ isis_init ()
 
   install_element (ISIS_NODE, &log_adj_changes_cmd);
   install_element (ISIS_NODE, &no_log_adj_changes_cmd);
+
+  spf_backoff_cmd_init();
 }
diff --git a/isisd/isisd.h b/isisd/isisd.h
index 87c4a0447..e1d3a69f8 100644
--- a/isisd/isisd.h
+++ b/isisd/isisd.h
@@ -127,6 +127,7 @@ struct isis_area
                                     [ZEBRA_ROUTE_MAX + 1][ISIS_LEVELS];
   struct route_table *ext_reach[REDIST_PROTOCOL_COUNT][ISIS_LEVELS];
 
+  struct spf_backoff *spf_delay_ietf[ISIS_LEVELS]; /*Structure with IETF SPF algo parameters*/
   struct thread *spf_timer[ISIS_LEVELS];
 
   QOBJ_FIELDS