sudo: schedule another full refresh in short interval if the first fails

https://fedorahosted.org/sssd/ticket/1689

If the first full refresh of sudo rules fails because the data provider
is offline, we will schedule another one in 2, 4, ... minutes.

2 files changed, 28 insertions, 0 deletions

diff --git a/src/providers/ldap/sdap_sudo.c b/src/providers/ldap/sdap_sudo.c
index c4f422ed..9a780b8e 100644
--- a/src/providers/ldap/sdap_sudo.c
+++ b/src/providers/ldap/sdap_sudo.c
@@ -30,6 +30,8 @@
 #include "providers/ldap/sdap_sudo_cache.h"
 #include "db/sysdb_sudo.h"
 
+#define SUDO_MAX_FIRST_REFRESH_DELAY 16
+
 struct sdap_sudo_full_refresh_state {
     struct sdap_sudo_ctx *sudo_ctx;
     struct sdap_id_ctx *id_ctx;
@@ -960,6 +962,7 @@ static void sdap_sudo_periodical_first_refresh_done(struct tevent_req *req)
     struct tevent_req *subreq = NULL; /* req from sdap_sudo_full_refresh_send() */
     struct sdap_sudo_ctx *sudo_ctx = NULL;
     time_t delay;
+    time_t timeout;
     int dp_error = DP_ERR_OK;
     int error = EOK;
     int ret;
@@ -999,6 +1002,30 @@ schedule:
         return;
     }
 
+    /* if we are offline, we will try to perform another full refresh */
+    if (dp_error == DP_ERR_OFFLINE) {
+        sudo_ctx->full_refresh_attempts++;
+        timeout = delay;
+        delay = sudo_ctx->full_refresh_attempts << 1;
+        if (delay > SUDO_MAX_FIRST_REFRESH_DELAY) {
+            delay = SUDO_MAX_FIRST_REFRESH_DELAY;
+        }
+
+        DEBUG(SSSDBG_TRACE_FUNC, ("Data provider is offline. "
+              "Scheduling another full refresh in %l minutes.\n", delay));
+
+        ret = sdap_sudo_schedule_refresh(sudo_ctx, sudo_ctx,
+                                         SDAP_SUDO_REFRESH_FULL,
+                                         sdap_sudo_periodical_first_refresh_done,
+                                         delay * 60, timeout);
+        if (ret != EOK) {
+            DEBUG(SSSDBG_OP_FAILURE, ("Unable to schedule full refresh of sudo "
+                  "rules! Periodical updates will not work!\n"));
+        }
+
+        return;
+    }
+
     ret = sdap_sudo_schedule_full_refresh(sudo_ctx, delay);
     if (ret != EOK) {
         DEBUG(SSSDBG_OP_FAILURE, ("Full periodical refresh will not work.\n"));
diff --git a/src/providers/ldap/sdap_sudo.h b/src/providers/ldap/sdap_sudo.h
index 5a12afd5..6384c7b8 100644
--- a/src/providers/ldap/sdap_sudo.h
+++ b/src/providers/ldap/sdap_sudo.h
@@ -31,6 +31,7 @@ struct sdap_sudo_ctx {
     bool use_host_filter;
 
     bool full_refresh_done;
+    int full_refresh_attempts;
 };
 
 enum sdap_sudo_refresh_type {