[trac925] Interface of the keyring updater

src/lib/server_common/Makefile.am

@@ -18,9 +18,12 @@ endif
 
 lib_LTLIBRARIES = libserver_common.la
 libserver_common_la_SOURCES = portconfig.h portconfig.cc
+libserver_common_la_SOURCES += keyring.h keyring.cc
 libserver_common_la_LIBADD = $(top_builddir)/src/lib/exceptions/libexceptions.la
 libserver_common_la_LIBADD += $(top_builddir)/src/lib/asiolink/libasiolink.la
 libserver_common_la_LIBADD += $(top_builddir)/src/lib/cc/libcc.la
+libserver_common_la_LIBADD += $(top_builddir)/src/lib/config/libcfgclient.la
 libserver_common_la_LIBADD += $(top_builddir)/src/lib/log/liblog.la
+libserver_common_la_LIBADD += $(top_builddir)/src/lib/dns/libdns++.la
 
 CLEANFILES = *.gcno *.gcda

src/lib/server_common/keyring.cc

+// Copyright (C) 2011  Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include <server_common/keyring.h>

src/lib/server_common/keyring.h

+// Copyright (C) 2011  Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#ifndef ISC_SERVER_COMMON_KEYRING_H
+#define ISC_SERVER_COMMON_KEYRING_H
+
+#include <boost/shared_ptr.hpp>
+#include <dns/tsigkey.h>
+#include <config/ccsession.h>
+
+/**
+ * \file keyring.h
+ * \brief TSIG keyring loaded from configuration.
+ *
+ * This file contains routines for loading a TSIG key ring from
+ * the tsig_keys configuration section and keeping them up to date
+ * on updates.
+ *
+ * You simply initialize/load the keyring with isc::server_common::initKeyring
+ * and then just use the key ring in in isc::server_common::keyring. It is
+ * automatically reloaded, when the configuration updates, so you no longer
+ * needs to care about it.
+ *
+ * If you want to keep a key (or session) for longer time or your application
+ * is multithreaded, you might want to have a copy of the shared pointer.
+ * Otherwise an update might replace the keyring and delete the keys in the
+ * old one.
+ */
+
+namespace isc {
+
+namespace server_common {
+
+/**
+ * \brief The key ring itself
+ *
+ * This is where the key ring is stored. You can directly use it to your needs,
+ * but you need to call initKeyring first, otherwise you'll find a NULL pointer
+ * here only.
+ */
+boost::shared_ptr<dns::TSIGKeyRing> keyring;
+
+/**
+ * \brief Load the key ring for the first time
+ *
+ * This loads the key ring from configuration to keyring. It also registers for
+ * config updates, so from now on, it'll be kept up to date.
+ *
+ * You can unload the key ring with deinitKeyring.
+ *
+ * If it is already loaded, this function does nothing. So, if more than one
+ * part of an application needs to use the key ring, they all can just call
+ * this independently to ensure the keyring is loaded.
+ *
+ * \param session The configuration session used to talk to the config manager.
+ */
+void initKeyring(config::ModuleCCSession& session);
+
+/**
+ * \brief Unload the key ring
+ *
+ * This can be used to unload the key ring. It will reset the keyring to NULL
+ * and stop receiving updates of the configuration.
+ *
+ * The need for this function should be quite rare, as it isn't required to be
+ * called before application shutdown. And not calling it has only small
+ * performance penalty -- the keyring will be kept in memory and updated when
+ * the user changes configuration.
+ *
+ * This does nothing if the key ring is not loaded currently.
+ *
+ * \param session The configuration session used to talk to the config manager.
+ */
+void deinitKeyring(config::ModuleCCSession& session);
+
+}
+}
+
+#endif