Replication version checking.

Whenever we upgrade IPA such that any data incompatibilities might occur
then we need to bump the DATA_VERSION value so that data will not
replicate to other servers. The idea is that you can do an in-place
upgrade of each IPA server and the different versions own't pollute
each other with bad data.

5 files changed, 274 insertions, 0 deletions

diff --git a/daemons/configure.ac b/daemons/configure.ac
index 7f0fd680f..5b5208974 100644
--- a/daemons/configure.ac
+++ b/daemons/configure.ac
@@ -264,6 +264,7 @@ AC_CONFIG_FILES([
     ipa-slapi-plugins/ipa-memberof/Makefile
     ipa-slapi-plugins/ipa-pwd-extop/Makefile
     ipa-slapi-plugins/ipa-winsync/Makefile
+    ipa-slapi-plugins/ipa-version/Makefile
 ])
 
 AC_OUTPUT
diff --git a/daemons/ipa-slapi-plugins/Makefile.am b/daemons/ipa-slapi-plugins/Makefile.am
index f5c237439..ae0a801cf 100644
--- a/daemons/ipa-slapi-plugins/Makefile.am
+++ b/daemons/ipa-slapi-plugins/Makefile.am
@@ -3,6 +3,7 @@ NULL =
 SUBDIRS =			\
 	ipa-enrollment		\
 	ipa-pwd-extop		\
+	ipa-version		\
 	ipa-winsync		\
 	$(NULL)
 
diff --git a/daemons/ipa-slapi-plugins/ipa-version/Makefile.am b/daemons/ipa-slapi-plugins/ipa-version/Makefile.am
new file mode 100644
index 000000000..331ce7f1b
--- /dev/null
+++ b/daemons/ipa-slapi-plugins/ipa-version/Makefile.am
@@ -0,0 +1,44 @@
+NULL =
+
+INCLUDES =							\
+	-I.							\
+	-I../../						\
+	-I$(srcdir)						\
+	-I/usr/include/dirsrv					\
+	-DPREFIX=\""$(prefix)"\" 				\
+	-DBINDIR=\""$(bindir)"\"				\
+	-DLIBDIR=\""$(libdir)"\" 				\
+	-DLIBEXECDIR=\""$(libexecdir)"\"			\
+	-DDATADIR=\""$(datadir)"\"				\
+	$(MOZLDAP_CFLAGS)					\
+	$(KRB5_CFLAGS)						\
+	$(WARN_CFLAGS)						\
+	$(NULL)
+
+plugindir = $(libdir)/dirsrv/plugins
+plugin_LTLIBRARIES = 			\
+	libipa_repl_version.la	\
+	$(NULL)
+
+libipa_repl_version_la_SOURCES = 	\
+	ipa_repl_version.c		\
+	$(NULL)
+
+libipa_repl_version_la_LDFLAGS = -avoid-version
+
+libipa_repl_version_la_LIBADD = 	\
+	$(MOZLDAP_LIBS)			\
+	$(NULL)
+
+appdir = $(IPA_DATA_DIR)
+app_DATA =			\
+	version-conf.ldif	\
+	$(NULL)
+
+EXTRA_DIST =			\
+	$(app_DATA)		\
+	$(NULL)
+
+MAINTAINERCLEANFILES =		\
+	*~			\
+	Makefile.in
diff --git a/daemons/ipa-slapi-plugins/ipa-version/ipa_repl_version.c b/daemons/ipa-slapi-plugins/ipa-version/ipa_repl_version.c
new file mode 100644
index 000000000..a93800134
--- /dev/null
+++ b/daemons/ipa-slapi-plugins/ipa-version/ipa_repl_version.c
@@ -0,0 +1,211 @@
+/** BEGIN COPYRIGHT BLOCK
+ * This Program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free Software
+ * Foundation; version 2 of the License.
+ *
+ * This Program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this Program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * In addition, as a special exception, Red Hat, Inc. gives You the additional
+ * right to link the code of this Program with code not covered under the GNU
+ * General Public License ("Non-GPL Code") and to distribute linked combinations
+ * including the two, subject to the limitations in this paragraph. Non-GPL Code
+ * permitted under this exception must only link to the code of this Program
+ * through those well defined interfaces identified in the file named EXCEPTION
+ * found in the source code files (the "Approved Interfaces"). The files of
+ * Non-GPL Code may instantiate templates or use macros or inline functions from
+ * the Approved Interfaces without causing the resulting work to be covered by
+ * the GNU General Public License. Only Red Hat, Inc. may make changes or
+ * additions to the list of Approved Interfaces. You must obey the GNU General
+ * Public License in all respects for all of the Program code and other code used
+ * in conjunction with the Program except the Non-GPL Code covered by this
+ * exception. If you modify this file, you may extend this exception to your
+ * version of the file, but you are not obligated to do so. If you do not wish to
+ * provide this exception without modification, you must delete this exception
+ * statement from your version and license this file solely under the GPL without
+ * exception.
+ *
+ *
+ * Copyright (C) 2010 Red Hat, Inc.
+ * All rights reserved.
+ * END COPYRIGHT BLOCK **/
+
+#include "slapi-plugin.h"
+#include "repl-session-plugin.h"
+#include "ipa-version.h"
+#include <string.h>
+
+/* Identify the type of data we're sending, an unsigned int in this case */
+#define REPL_VERSION_DATA_GUID "2D562D8B-2F30-4447-AF76-2B721D1D5F6A"
+
+static char *repl_version_plugin_name = "ipa_replication_version";
+static char *data_version = NULL;
+
+/*
+ * Plugin identifiers
+ */
+static Slapi_PluginDesc repl_version_pdesc = {
+    "ipa-repl-version-plugin",
+    "Red Hat, Inc.",
+    "1.0",
+    "IPA Replication version plugin"
+};
+
+static Slapi_ComponentId *repl_version_plugin_id = NULL;
+
+
+/*
+ * Replication Version Callbacks
+ */
+
+/*
+ * This is called on a master when we are about to acquire a
+ * replica.
+ *
+ * Returning non-0 will abort the replication session.  This
+ * results in the master going into incremental backoff mode.
+ */
+static int
+repl_version_plugin_pre_acquire_cb(void *cookie, const Slapi_DN *repl_subtree,
+                                        int is_total, char **data_guid, struct berval **data)
+{
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+        "repl_version_plugin_pre_acquire_cb() called for suffix \"%s\", "
+        "is_total: \"%s\".\n", slapi_sdn_get_ndn(repl_subtree),
+        is_total ? "TRUE" : "FALSE");
+
+    /* allocate some data to be sent to the replica */
+    *data_guid = slapi_ch_smprintf("%s", REPL_VERSION_DATA_GUID);
+    *data = (struct berval *)slapi_ch_malloc(sizeof(struct berval));
+    (*data)->bv_val = slapi_ch_smprintf("%s", data_version);
+    (*data)->bv_len = strlen((*data)->bv_val) + 1;
+
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+        "repl_version_plugin_pre_acquire_cb() sending data: guid: \"%s\" data: \"%s\".\n",
+    *data_guid, (*data)->bv_val);
+
+    return 0;
+}
+
+/*
+ * This is called on a replica when it receives a start replication
+ * extended operation from a master.
+ *
+ * The data sent by the master (version) is compared with our own
+ * hardcoded version to determine if replication can proceed or not.
+ *
+ * The replication plug-in will take care of freeing data_guid and data.
+ *
+ * Returning non-0 will abort the replication session.  This
+ * results in the master going into incremental backoff mode.
+ */
+static int
+repl_version_plugin_recv_acquire_cb(const char *repl_subtree, int is_total,
+                                         const char *data_guid, const struct berval *data)
+{
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+        "test_repl_session_plugin_recv_acquire_cb() called for suffix \"%s\", is_total: \"%s\".\n",
+        repl_subtree, is_total ? "TRUE" : "FALSE");
+
+    /* compare our data version to the master data version */
+    if (data_guid && data && (strcmp(data_guid, REPL_VERSION_DATA_GUID) == 0)) {
+        slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+            "repl_version_plugin_recv_acquire_cb() received data: guid: \"%s\" data: \"%s\".\n",
+            data_guid, data->bv_val);
+        if (!(strcmp(data_version, data->bv_val) == 0)) {
+            slapi_log_error(SLAPI_LOG_FATAL, repl_version_plugin_name,
+                "Incompatible IPA versions, pausing replication. This server: \"%s\" remote server: \"%s\".\n", data_version, data->bv_val);
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
+/*
+ * Callback list for registering API
+ */
+static void *repl_version_api[] = {
+    NULL, /* reserved for api broker use, must be zero */
+    NULL, /* init cb */
+    repl_version_plugin_pre_acquire_cb,
+    NULL, /* reply_acquire_cb */
+    NULL, /* post_acquire_cb */
+    repl_version_plugin_recv_acquire_cb,
+    NULL /* destroy cb */
+};
+
+/*
+ * Plug-in framework functions
+ */
+static int
+repl_version_plugin_start(Slapi_PBlock *pb)
+{
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                    "--> repl_version_plugin_start -- begin\n");
+
+    data_version = slapi_ch_smprintf("%llu", DATA_VERSION);
+
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                    "<-- repl_version_plugin_start -- end\n");
+    return 0;
+}
+
+static int
+repl_version_plugin_close(Slapi_PBlock *pb)
+{
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                    "--> repl_version_plugin_close -- begin\n");
+
+    slapi_apib_unregister(REPL_SESSION_v1_0_GUID);
+
+    slapi_ch_free_string(&data_version);
+
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                    "<-- repl_version_plugin_close -- end\n");
+    return 0;
+}
+
+int repl_version_plugin_init(Slapi_PBlock *pb)
+{
+    slapi_log_error(SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                    "--> repl_version_plugin_init -- begin\n");
+
+    if ( slapi_pblock_set( pb, SLAPI_PLUGIN_VERSION,
+                           SLAPI_PLUGIN_VERSION_01 ) != 0 ||
+         slapi_pblock_set(pb, SLAPI_PLUGIN_START_FN,
+                          (void *) repl_version_plugin_start ) != 0 ||
+         slapi_pblock_set(pb, SLAPI_PLUGIN_CLOSE_FN,
+                          (void *) repl_version_plugin_close ) != 0 ||
+         slapi_pblock_set( pb, SLAPI_PLUGIN_DESCRIPTION,
+                           (void *)&repl_version_pdesc ) != 0 )
+    {
+        slapi_log_error( SLAPI_LOG_FATAL, repl_version_plugin_name,
+                         "<-- repl_version_plugin_init -- failed to register plugin -- end\n");
+        return -1;
+    }
+
+    if( slapi_apib_register(REPL_SESSION_v1_0_GUID, repl_version_api) ) {
+        slapi_log_error( SLAPI_LOG_FATAL, repl_version_plugin_name,
+                         "<-- repl_version_plugin_start -- failed to register repl_version api -- end\n");
+        return -1;
+    }
+
+
+    /* Retrieve and save the plugin identity to later pass to
+       internal operations */
+    if (slapi_pblock_get(pb, SLAPI_PLUGIN_IDENTITY, &repl_version_plugin_id) != 0) {
+        slapi_log_error(SLAPI_LOG_FATAL, repl_version_plugin_name,
+                         "<-- repl_version_plugin_init -- failed to retrieve plugin identity -- end\n");
+        return -1;
+    }
+
+    slapi_log_error( SLAPI_LOG_PLUGIN, repl_version_plugin_name,
+                     "<-- repl_version_plugin_init -- end\n");
+    return 0;
+}
diff --git a/daemons/ipa-slapi-plugins/ipa-version/version-conf.ldif b/daemons/ipa-slapi-plugins/ipa-version/version-conf.ldif
new file mode 100644
index 000000000..99e43597a
--- /dev/null
+++ b/daemons/ipa-slapi-plugins/ipa-version/version-conf.ldif
@@ -0,0 +1,17 @@
+dn: cn=IPA Version Replication,cn=plugins,cn=config
+changetype: add
+objectclass: top
+objectclass: nsSlapdPlugin
+objectclass: extensibleObject
+cn: IPA Version Replication
+nsslapd-pluginpath: libipa_repl_version
+nsslapd-plugininitfunc: repl_version_plugin_init
+nsslapd-plugintype: preoperation
+nsslapd-pluginenabled: on
+nsslapd-pluginid: ipa_repl_version
+nsslapd-pluginversion: 1.0
+nsslapd-pluginvendor: Red Hat, Inc.
+nsslapd-plugindescription: IPA Replication version plugin
+nsslapd-plugin-depends-on-type: database
+nsslapd-plugin-depends-on-named: Multimaster Replication Plugin
+