From 9c657d5d72569af8c650170913328d3fc5f9b3d9 Mon Sep 17 00:00:00 2001
From: Rich Megginson <rmeggins@redhat.com>
Date: Sep 18 2013 18:52:44 +0000
Subject: Ticket #47516 replication stops with excessive clock skew


https://fedorahosted.org/389/ticket/47516
Reviewed by: nhosoi (Thanks!)
Branch: master
Fix Description: Add a new configuration parameter to cn=config
nsslapd-ignore-time-skew: on|off - default off
If nsslapd-ignore-time-skew: on, the replication consumer will log errors
about excessive time skew, but will allow replication to proceed, and will
not return a time skew error to the replication supplier.
Platforms tested: RHEL6 x86_64
Flag Day: no
Doc impact: yes - document new config param

---

diff --git a/ldap/servers/plugins/replication/repl_extop.c b/ldap/servers/plugins/replication/repl_extop.c
index 68aed62..f7f1d36 100644
--- a/ldap/servers/plugins/replication/repl_extop.c
+++ b/ldap/servers/plugins/replication/repl_extop.c
@@ -835,12 +835,19 @@ multimaster_extop_StartNSDS50ReplicationRequest(Slapi_PBlock *pb)
 				rc = replica_update_csngen_state_ext (replica, supplier_ruv, replicacsn); /* too much skew */
 				if (rc == CSN_LIMIT_EXCEEDED)
 				{
-					response = NSDS50_REPL_EXCESSIVE_CLOCK_SKEW;
+					extern int config_get_ignore_time_skew();
+
 					slapi_log_error(SLAPI_LOG_FATAL, repl_plugin_name,
 									"conn=%" NSPRIu64 " op=%d repl=\"%s\": "
 									"Excessive clock skew from supplier RUV\n",
 									connid, opid, repl_root);
-					goto send_response;
+					if (!config_get_ignore_time_skew()) {
+						response = NSDS50_REPL_EXCESSIVE_CLOCK_SKEW;
+						goto send_response;
+					} else {
+						/* else just continue */
+						rc = 0;
+					}
 				}
 				else if (rc != 0)
 				{
diff --git a/ldap/servers/slapd/libglobs.c b/ldap/servers/slapd/libglobs.c
index 413351d..dd3909f 100644
--- a/ldap/servers/slapd/libglobs.c
+++ b/ldap/servers/slapd/libglobs.c
@@ -687,6 +687,10 @@ static struct config_get_and_set {
 		NULL, 0,
 		(void**)&global_slapdFrontendConfig.disk_logging_critical,
 		CONFIG_ON_OFF, (ConfigGetFunc)config_get_disk_logging_critical},
+	{CONFIG_IGNORE_TIME_SKEW, config_set_ignore_time_skew,
+		NULL, 0,
+		(void**)&global_slapdFrontendConfig.ignore_time_skew,
+		CONFIG_ON_OFF, (ConfigGetFunc)config_get_ignore_time_skew}
 #ifdef MEMPOOL_EXPERIMENTAL
 	,{CONFIG_MEMPOOL_SWITCH_ATTRIBUTE, config_set_mempool_switch,
 		NULL, 0,
@@ -1088,6 +1092,7 @@ FrontendConfig_init () {
   cfg->disk_grace_period = 60; /* 1 hour */
   cfg->disk_logging_critical = LDAP_OFF;
 
+  cfg->ignore_time_skew = LDAP_OFF;
 #ifdef MEMPOOL_EXPERIMENTAL
   cfg->mempool_switch = LDAP_ON;
   cfg->mempool_maxfreelist = 1024;
@@ -6141,6 +6146,31 @@ config_set_default_naming_context(const char *attrname,
     return LDAP_SUCCESS;
 }
 
+int
+config_get_ignore_time_skew(void)
+{
+    int retVal;
+    slapdFrontendConfig_t *slapdFrontendConfig = getFrontendConfig();
+    CFG_LOCK_READ(slapdFrontendConfig);
+    retVal = slapdFrontendConfig->ignore_time_skew;
+    CFG_UNLOCK_READ(slapdFrontendConfig);
+
+    return retVal;
+}
+
+int
+config_set_ignore_time_skew( const char *attrname, char *value,
+                            char *errorbuf, int apply )
+{
+    int retVal = LDAP_SUCCESS;
+    slapdFrontendConfig_t *slapdFrontendConfig = getFrontendConfig();
+
+    retVal = config_set_onoff(attrname, value,
+                              &(slapdFrontendConfig->ignore_time_skew),
+                              errorbuf, apply);
+    return retVal;
+}
+
 /*
  * This function is intended to be used from the dse code modify callback.  It
  * is "optimized" for that case because it takes a berval** of values, which is
diff --git a/ldap/servers/slapd/proto-slap.h b/ldap/servers/slapd/proto-slap.h
index 9d3a16d..dd6b236 100644
--- a/ldap/servers/slapd/proto-slap.h
+++ b/ldap/servers/slapd/proto-slap.h
@@ -390,6 +390,7 @@ int config_set_disk_threshold( const char *attrname, char *value, char *errorbuf
 int config_set_disk_grace_period( const char *attrname, char *value, char *errorbuf, int apply );
 int config_set_disk_logging_critical( const char *attrname, char *value, char *errorbuf, int apply );
 int config_set_auditlog_unhashed_pw(const char *attrname, char *value, char *errorbuf, int apply);
+int config_set_ignore_time_skew(const char *attrname, char *value, char *errorbuf, int apply);
 
 #if !defined(_WIN32) && !defined(AIX)
 int config_set_maxdescriptors( const char *attrname, char *value, char *errorbuf, int apply );
@@ -544,6 +545,7 @@ int config_get_disk_monitoring();
 PRUint64 config_get_disk_threshold();
 int config_get_disk_grace_period();
 int config_get_disk_logging_critical();
+int config_get_ignore_time_skew();
 
 int is_abspath(const char *);
 char* rel2abspath( char * );
diff --git a/ldap/servers/slapd/slap.h b/ldap/servers/slapd/slap.h
index 403ea8a..49d61f0 100644
--- a/ldap/servers/slapd/slap.h
+++ b/ldap/servers/slapd/slap.h
@@ -2002,6 +2002,7 @@ typedef struct _slapdEntryPoints {
 #define CONFIG_DISK_THRESHOLD "nsslapd-disk-monitoring-threshold"
 #define CONFIG_DISK_GRACE_PERIOD "nsslapd-disk-monitoring-grace-period"
 #define CONFIG_DISK_LOGGING_CRITICAL "nsslapd-disk-monitoring-logging-critical"
+#define CONFIG_IGNORE_TIME_SKEW "nsslapd-ignore-time-skew"
 
 #ifdef MEMPOOL_EXPERIMENTAL
 #define CONFIG_MEMPOOL_SWITCH_ATTRIBUTE "nsslapd-mempool"
@@ -2236,6 +2237,7 @@ typedef struct _slapdFrontendConfig {
   PRUint64 disk_threshold;
   int disk_grace_period;
   int disk_logging_critical;
+  int ignore_time_skew;
 } slapdFrontendConfig_t;
 
 /* possible values for slapdFrontendConfig_t.schemareplace */