RADIUS client: fix extra retry before failover

This commit changes the failover behavior of RADIUS client. Commit
27ebadccfb2 ("RADIUS client: Cease endless retry for message for
multiple servers") changed the retry logic, causing RADIUS client to
wait RADIUS_CLIENT_NUM_FAILOVER + 1 timeouts before failing over the
first time. Prior to that commit, RADIUS client would wait
RADIUS_CLIENT_NUM_FAILOVER timeouts before each failover. This was
caused by moving the entry->attempts > RADIUS_CLIENT_NUM_FAILOVER
comparison to before the retry attempt, where entry->attempts is
incremented.

The commit in question set entry->attempts in radius_change_server to 1
instead of 0, so RADIUS client would still only wait
RADIUS_CLIENT_NUM_FAILOVER timeouts for subsequent failovers, the same
as the original behavior.

This commit changes the comparison so the initial failover now happens
after waiting RADIUS_CLIENT_NUM_FAILOVER timeouts, as it did originally.
It also changes the RADIUS_CLIENT_MAX_FAILOVER comparison to prevent an
additional attempt to the primary server after the final failover.

Signed-off-by: Ethan Everett <ethan.everett@meraki.net>

diff --git a/src/radius/radius_client.c b/src/radius/radius_client.c
index a3db4048c4a7ad3d439b0ffdf4a07e97edef6704..2b7a604eda242aefaaaa513210ccbce2d4bae761 100644 (file)
--- a/src/radius/radius_client.c
+++ b/src/radius/radius_client.c
@@ -457,7 +457,7 @@ static int radius_client_retransmit(struct radius_client_data *radius,
        }
 
        /* retransmit; remove entry if too many attempts */
-       if (entry->accu_attempts > RADIUS_CLIENT_MAX_FAILOVER *
+       if (entry->accu_attempts >= RADIUS_CLIENT_MAX_FAILOVER *
            RADIUS_CLIENT_NUM_FAILOVER * num_servers) {
                wpa_printf(MSG_INFO,
                           "RADIUS: Removing un-ACKed message due to too many failed retransmit attempts");
@@ -507,7 +507,7 @@ static void radius_client_timer(void *eloop_ctx, void *timeout_ctx)
                if (now.sec >= entry->next_try) {
                        s = entry->msg_type == RADIUS_AUTH ? radius->auth_sock :
                                radius->acct_sock;
-                       if (entry->attempts > RADIUS_CLIENT_NUM_FAILOVER ||
+                       if (entry->attempts >= RADIUS_CLIENT_NUM_FAILOVER ||
                            (s < 0 && entry->attempts > 0)) {
                                if (entry->msg_type == RADIUS_ACCT ||
                                    entry->msg_type == RADIUS_ACCT_INTERIM)
@@ -1116,7 +1116,7 @@ radius_change_server(struct radius_client_data *radius,
                    (!auth && entry->msg_type != RADIUS_ACCT))
                        continue;
                entry->next_try = entry->first_try + RADIUS_CLIENT_FIRST_WAIT;
-               entry->attempts = 1;
+               entry->attempts = 0;
                entry->next_wait = RADIUS_CLIENT_FIRST_WAIT * 2;
        }