- Break ack queue chain when a lease is removed from the ack queue, so that

  its successor doesn't wind up back on the update queue when the lease is
  next updated.
- Print the reject reason when a BNDACK includes one, but still remove the
  lease from the update queue.
- Don't use the lease to send the BNDACK, since there may not be one locally.
- Support contact message, and inter-message-arrival timeouts.

diff --git a/server/failover.c b/server/failover.c
index 07539b8de2f059e518712ece61dc6f9b902d511b..05ecaff45eb413c5d19885f3240869f9ad2db541 100644 (file)
--- a/server/failover.c
+++ b/server/failover.c
@@ -43,7 +43,7 @@
 
 #ifndef lint
 static char copyright[] =
-"$Id: failover.c,v 1.16 2000/06/02 21:27:17 mellon Exp $ Copyright (c) 1999-2000 The Internet Software Consortium.  All rights reserved.\n";
+"$Id: failover.c,v 1.17 2000/06/07 00:05:17 mellon Exp $ Copyright (c) 1999-2000 The Internet Software Consortium.  All rights reserved.\n";
 #endif /* not lint */
 
 #include "dhcpd.h"
@@ -1123,6 +1123,7 @@ isc_result_t dhcp_failover_state_signal (omapi_object_t *o,
                        dhcp_failover_send_disconnect ((omapi_object_t *)link,
                                                       reason, errmsg);
                        omapi_disconnect (link -> outer, 0);
+                       return ISC_R_SUCCESS;
                    }
 
                    if (state -> link_to_peer) {
@@ -1134,6 +1135,16 @@ isc_result_t dhcp_failover_state_signal (omapi_object_t *o,
                    dhcp_failover_link_reference (&state -> link_to_peer,
                                                  link, MDL);
                    dhcp_failover_state_transition (state, "connect");
+                   add_timeout (cur_time +
+                                (int)state -> max_transmit_idle,
+                                dhcp_failover_send_contact, state,
+                                (tvref_t)dhcp_failover_state_reference,
+                                (tvunref_t)dhcp_failover_state_dereference);
+                   add_timeout (cur_time +
+                                (int)state -> max_response_delay,
+                                dhcp_failover_timeout, state,
+                                (tvref_t)dhcp_failover_state_reference,
+                                (tvunref_t)dhcp_failover_state_dereference);
                } else if (link -> imsg -> type == FTM_DISCONNECT) {
                    if (link -> imsg -> reject_reason) {
                        log_error ("Failover DISCONNECT from %d.%d.%d.%d%s%s",
@@ -1150,7 +1161,6 @@ isc_result_t dhcp_failover_state_signal (omapi_object_t *o,
                                    (link -> imsg -> reject_reason)));
                    }
                    omapi_disconnect (link -> outer, 1);
-                   return ISC_R_SUCCESS;
                } else if (link -> imsg -> type == FTM_BNDUPD) {
                        dhcp_failover_process_bind_update (state,
                                                           link -> imsg);
@@ -1165,6 +1175,16 @@ isc_result_t dhcp_failover_state_signal (omapi_object_t *o,
                }
        }
 
+       /* Add a timeout so that if the partner doesn't send another message
+          for the maximum transmit idle time plus a grace of one second,
+          we close the connection. */
+       if (state -> my_state == normal)
+               add_timeout (cur_time +
+                            (int)state -> max_response_delay,
+                            dhcp_failover_timeout, state,
+                            (tvref_t)dhcp_failover_state_reference,
+                            (tvunref_t)dhcp_failover_state_dereference);
+
        /* Handle all the events we care about... */
        return ISC_R_SUCCESS;
 }
@@ -1579,10 +1599,12 @@ void dhcp_failover_ack_queue_remove (dhcp_failover_state_t *state,
                if (lease -> next_pending) {
                        lease_reference (&state -> ack_queue_head,
                                         lease -> next_pending, MDL);
+                       lease_dereference (&lease -> next_pending, MDL);
                } else {
                        lease_dereference (&state -> ack_queue_tail, MDL);
                }
                lease -> flags &= ~ON_ACK_QUEUE;
+               state -> cur_unacked_updates--;
                return;
        }
        for (lp = state -> ack_queue_head;
@@ -1590,15 +1612,17 @@ void dhcp_failover_ack_queue_remove (dhcp_failover_state_t *state,
                ;
        if (lp) {
                lease_dereference (&lp -> next_pending, MDL);
-               if (lease -> next_pending)
+               if (lease -> next_pending) {
                        lease_reference (&lp -> next_pending,
                                         lease -> next_pending, MDL);
-               else {
+                       lease_dereference (&lease -> next_pending, MDL);
+               } else {
                        lease_dereference (&state -> ack_queue_tail, MDL);
                        lease_reference (&state -> ack_queue_tail, lp, MDL);
                }
        }
        lease -> flags &= ~ON_ACK_QUEUE;
+       state -> cur_unacked_updates--;
 }
 
 isc_result_t dhcp_failover_state_set_value (omapi_object_t *h,
@@ -2514,6 +2538,13 @@ isc_result_t dhcp_failover_put_message (dhcp_failover_link_t *link,
        if (status != ISC_R_SUCCESS)
                goto err;
        dfree (opbuf, MDL);
+       if (link -> state_object &&
+           link -> state_object -> link_to_peer == link)
+               add_timeout (cur_time +
+                            (int)link -> state_object -> max_transmit_idle,
+                            dhcp_failover_send_contact, link -> state_object,
+                            (tvref_t)dhcp_failover_state_reference,
+                            (tvunref_t)dhcp_failover_state_dereference);
        return status;
 
       err:
@@ -2522,6 +2553,69 @@ isc_result_t dhcp_failover_put_message (dhcp_failover_link_t *link,
        return status;
 }
 
+void dhcp_failover_timeout (void *vstate)
+{
+       dhcp_failover_state_t *state = vstate;
+       dhcp_failover_link_t *link;
+       isc_result_t status;
+
+       if (!state || state -> type != dhcp_type_failover_state)
+               return;
+       if (state -> my_state != normal)
+               return;
+       link = state -> link_to_peer;
+       if (!link ||
+           !link -> outer ||
+           link -> outer -> type != omapi_type_connection)
+               return;
+
+       log_error ("timeout waiting for failover peer %s", state -> name);
+
+       /* If we haven't gotten a timely response, blow away the connection.
+          This will cause the state to change automatically. */
+       omapi_disconnect (link -> outer, 1);
+}
+
+void dhcp_failover_send_contact (void *vstate)
+{
+       dhcp_failover_state_t *state = vstate;
+       dhcp_failover_link_t *link;
+       isc_result_t status;
+
+#if defined (DEBUG_FAILOVER_MESSAGES)  
+       char obuf [64];
+       unsigned obufix = 0;
+       
+# define FMA obuf, &obufix, sizeof obuf
+       failover_print (FMA, "(contact");
+#else
+# define FMA (unsigned char *)0, (unsigned *)0, 0
+#endif
+
+       if (!state || state -> type != dhcp_type_failover_state)
+               return;
+       link = state -> link_to_peer;
+       if (!link ||
+           !link -> outer ||
+           link -> outer -> type != omapi_type_connection)
+               return;
+
+       status = (dhcp_failover_put_message
+                 (link, link -> outer,
+                  FTM_CONTACT,
+                  (failover_option_t *)0));
+
+#if defined (DEBUG_FAILOVER_MESSAGES)
+       if (status != ISC_R_SUCCESS)
+               failover_print (FMA, " (failed)");
+       failover_print (FMA, ")");
+       if (obufix) {
+               log_debug ("%s", obuf);
+       }
+#endif
+       return;
+}
+
 /* Send a connect message. */
 
 isc_result_t dhcp_failover_send_connect (omapi_object_t *l)
@@ -2805,19 +2899,19 @@ isc_result_t dhcp_failover_send_bind_ack (dhcp_failover_state_t *state,
                  (link, link -> outer,
                   FTM_BNDACK,
                   dhcp_failover_make_option (FTO_ASSIGNED_IP_ADDRESS, FMA,
-                                             lease -> ip_addr.len,
-                                             lease -> ip_addr.iabuf),
+                                             sizeof msg -> assigned_addr,
+                                             &msg -> assigned_addr),
                   dhcp_failover_make_option (FTO_BINDING_STATUS, FMA,
-                                             lease -> binding_state),
-                  lease -> uid_len
+                                             msg -> binding_status),
+                  (msg -> options_present & FTB_CLIENT_IDENTIFIER)
                   ? dhcp_failover_make_option (FTO_CLIENT_IDENTIFIER, FMA,
-                                               lease -> uid_len,
-                                               lease -> uid)
+                                               msg -> client_identifier.count,
+                                               msg -> client_identifier.data)
                   : &skip_failover_option,
-                  lease -> hardware_addr.hlen
+                  (msg -> options_present & FTB_CHADDR)
                   ? dhcp_failover_make_option (FTO_CHADDR, FMA,
-                                               lease -> hardware_addr.hlen,
-                                               lease -> hardware_addr.hbuf)
+                                               msg -> chaddr.count,
+                                               msg -> chaddr.data)
                   : &skip_failover_option,
                   dhcp_failover_make_option (FTO_LEASE_EXPIRY, FMA,
                                              msg -> expiry),
@@ -2943,6 +3037,7 @@ isc_result_t dhcp_failover_process_bind_update (dhcp_failover_state_t *state,
        memcpy (ia.iabuf, &msg -> assigned_addr, ia.len);
 
        lease = (struct lease *)0;
+       lt = (struct lease *)0;
        if (!find_lease_by_ip_addr (&lease, ia, MDL)) {
                message = "unknown IP address";
                reason = FTR_ILLEGAL_IP_ADDR;
@@ -2952,7 +3047,6 @@ isc_result_t dhcp_failover_process_bind_update (dhcp_failover_state_t *state,
        /* XXX check for conflicts. */
 
        /* Install the new info. */
-       lt = (struct lease *)0;
        if (!lease_copy (&lt, lease, MDL)) {
                message = "no memory";
                goto bad;
@@ -3022,7 +3116,8 @@ isc_result_t dhcp_failover_process_bind_update (dhcp_failover_state_t *state,
                dhcp_failover_send_bind_ack (state, lease, msg, 0, 0);
        if (lt)
                lease_dereference (&lt, MDL);
-       lease_dereference (&lease, MDL);
+       if (lease)
+               lease_dereference (&lease, MDL);
 
        return ISC_R_SUCCESS;
 }
@@ -3030,7 +3125,8 @@ isc_result_t dhcp_failover_process_bind_update (dhcp_failover_state_t *state,
 isc_result_t dhcp_failover_process_bind_ack (dhcp_failover_state_t *state,
                                             failover_message_t *msg)
 {
-       struct lease *lt, *lease = (struct lease *)0;
+       struct lease *lt = (struct lease *)0;
+       struct lease *lease = (struct lease *)0;
        struct iaddr ia;
        const char *message = "no memory";
 
@@ -3043,9 +3139,21 @@ isc_result_t dhcp_failover_process_bind_ack (dhcp_failover_state_t *state,
        }
 
        /* XXX check for conflicts. */
+       if (msg -> options_present & FTB_REJECT_REASON) {
+               log_error ("bind update on %s from %s rejected: %.*s",
+                          piaddr (ia), state -> name,
+                          (int)((msg -> options_present & FTB_MESSAGE)
+                                ? msg -> message.count
+                                : strlen (dhcp_failover_reject_reason_print
+                                          (msg -> reject_reason))),
+                          (msg -> options_present & FTB_MESSAGE)
+                          ? (const char *)(msg -> message.data)
+                          : (dhcp_failover_reject_reason_print
+                             (msg -> reject_reason)));
+               goto unqueue;
+       }
 
        /* Install the new info. */
-       lt = (struct lease *)0;
        if (!lease_copy (&lt, lease, MDL)) {
                lease_dereference (&lease, MDL);
                goto bad;
@@ -3059,7 +3167,7 @@ isc_result_t dhcp_failover_process_bind_ack (dhcp_failover_state_t *state,
        /* Try to install the new information. */
        supersede_lease (lease, lt, 1, 0, 0);
 
-       state -> cur_unacked_updates--;
+      unqueue:
        dhcp_failover_ack_queue_remove (state, lease);
 
        /* If there are updates pending, we've created space to send at