wip

8 files changed, 443 insertions, 72 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 0746ad4..cd274f1 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -1,3 +1,3 @@
 # This Makefile is in the public domain
 AM_CPPFLAGS = -I$(top_srcdir)/src/include
-SUBDIRS = include syncdb sync lib
+SUBDIRS = include util syncdb sync lib
diff --git a/src/include/sync_database_plugin.h b/src/include/sync_database_plugin.h
index 5563cf3..b847888 100644
--- a/src/include/sync_database_plugin.h
+++ b/src/include/sync_database_plugin.h
@@ -1,25 +1,25 @@
 /*
-  This file is part of Sync
+  This file is part of GNU Taler
   Copyright (C) 2019 Taler Systems SA
 
-  Sync is free software; you can redistribute it and/or modify it under the
+  Taler is free software; you can redistribute it and/or modify it under the
   terms of the GNU Lesser General Public License as published by the Free Software
   Foundation; either version 3, or (at your option) any later version.
 
-  Sync is distributed in the hope that it will be useful, but WITHOUT ANY
+  Taler 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
-  Sync; see the file COPYING.GPL.  If not, see <http://www.gnu.org/licenses/>
+  Taler; see the file COPYING.GPL.  If not, see <http://www.gnu.org/licenses/>
 */
 /**
  * @file include/sync_database_plugin.h
  * @brief database access for Sync
  * @author Christian Grothoff
  */
-#ifndef TALER_SYNC_DATABASE_PLUGIN_H
-#define TALER_SYNC_DATABASE_PLUGIN_H
+#ifndef SYNC_DATABASE_PLUGIN_H
+#define SYNC_DATABASE_PLUGIN_H
 
 #include <gnunet/gnunet_util_lib.h>
 #include <sync_error_codes.h>
@@ -28,6 +28,79 @@
 #include <taler/taler_util.h>
 
 /**
+ * Private key identifying an account.
+ */
+struct SYNC_AccountPrivateKey
+{
+  /**
+   * We use EdDSA.
+   */
+  struct GNUNET_EdDSAPrivateKey eddsa_priv;
+};
+
+
+/**
+ * Public key identifying an account.
+ */
+struct SYNC_AccountPublicKey
+{
+  /**
+   * We use EdDSA.
+   */
+  struct GNUNET_EdDSAPrivateKey eddsa_priv;
+};
+
+
+/**
+ * Signature made with an account's public key.
+ */
+struct SYNC_AccountSignature
+{
+  /**
+   * We use EdDSA.
+   */
+  struct GNUNET_EdDSASignature eddsa_sig;
+};
+
+
+/**
+ * Possible status codes returned from the SYNC database.
+ */
+enum SYNC_DB_QueryStatus
+{
+  /**
+   * Update failed because the old backup hash does not match what we previously had in the DB.
+   */
+  SYNC_DB_OLD_BACKUP_MISSMATCH = -4,
+
+  /**
+   * Account is unpaid.
+   */
+  SYNC_DB_QS_PAYMENT_REQUIRED = -3,
+
+  /**
+   * Hard database issue, retries futile.
+   */
+  SYNC_DB_HARD_ERROR = -2,
+
+  /**
+   * Soft database error, retrying may help.
+   */
+  SYNC_DB_SOFT_ERROR = -1,
+
+  /**
+   * Database succeeded, but no results.
+   */
+  SYNC_DB_NO_RESULTS = 0,
+
+  /**
+   * Database succeeded, one change or result.
+   */
+  SYNC_DB_ONE_RESULT = 1
+};
+
+
+/**
  * Handle to interact with the database.
  *
  * Functions ending with "_TR" run their OWN transaction scope
@@ -67,51 +140,85 @@ struct SYNC_DatabasePlugin
    * truth and financial records older than @a fin_expire.
    *
    * @param cls closure
-   * @param fin_expire financial records older than the given
-   *        time stamp should be garbage collected (usual
-   *        values might be something like 6-10 years in the past)
+   * @param expire backups older than the given time stamp should be garbage collected
    * @return transaction status
    */
   enum SYNC_DB_QueryStatus
   (*gc)(void *cls,
-        struct GNUNET_TIME_Absolute fin_expire);
+        struct GNUNET_TIME_Absolute expire);
 
   /**
-  * Do a pre-flight check that we are not in an uncommitted transaction.
-  * If we are, try to commit the previous transaction and output a warning.
-  * Does not return anything, as we will continue regardless of the outcome.
-  *
-  * @param cls the `struct PostgresClosure` with the plugin-specific state
-  */
-  void
-  (*preflight) (void *cls);
-
-  /**
-  * Check that the database connection is still up.
-  *
-  * @param pg connection to check
-  */
-  void
-  (*check_connection) (void *cls);
+   * Store backup. Only applicable for the FIRST backup under
+   * an @a account_pub. Use @e update_backup_TR to update an
+   * existing backup.
+   *
+   * @param cls closure
+   * @param account_pub account to store @a backup under
+   * @param account_sig signature affirming storage request
+   * @param backup_hash hash of @a backup
+   * @param backup_size number of bytes in @a backup
+   * @param backup raw data to backup
+   * @return transaction status
+   */
+  enum SYNC_DB_QueryStatus
+  (*store_backup_TR)(void *cls,
+                     const struct SYNC_AccountPublicKey *account_pub,
+                     const struct SYNC_AccountSignature *account_sig,
+                     const struct GNUNET_HashCode *backup_hash,
+                     size_t backup_size,
+                     const void *backup);
 
   /**
-   * Store backup.
+   * Update backup.
    *
    * @param cls closure
+   * @param account_pub account to store @a backup under
+   * @param account_sig signature affirming storage request
+   * @param old_backup_hash hash of the previous backup (must match)
+   * @param backup_hash hash of @a backup
+   * @param backup_size number of bytes in @a backup
+   * @param backup raw data to backup
    * @return transaction status
    */
-  enum GNUNET_DB_QueryStatus
-  (*store_backup)(void *cls,
-                  ...);
+  enum SYNC_DB_QueryStatus
+  (*update_backup_TR)(void *cls,
+                      const struct SYNC_AccountPublicKey *account_pub,
+                      const struct GNUNET_HashCode *old_backup_hash,
+                      const struct SYNC_AccountSignature *account_sig,
+                      const struct GNUNET_HashCode *backup_hash,
+                      size_t backup_size,
+                      const void *backup);
 
   /**
    * Obtain backup.
    *
    * @param cls closure
+   * @param account_pub account to store @a backup under
+   * @param account_sig[OUT] set to signature affirming storage request
+   * @param backup_hash[OUT] set to hash of @a backup
+   * @param backup_size[OUT] set to number of bytes in @a backup
+   * @param backup[OUT] set to raw data to backup, caller MUST FREE
    */
-  enum GNUNET_DB_QueryStatus
-  (*lookup_backup)(void *cls,
-                   ...);
+  enum SYNC_DB_QueryStatus
+  (*lookup_backup_TR)(void *cls,
+                      const struct SYNC_AccountPublicKey *account_pub,
+                      struct SYNC_AccountSignature *account_sig,
+                      struct GNUNET_HashCode *backup_hash,
+                      size_t *backup_size,
+                      void **backup);
+
+  /**
+   * Increment account lifetime.
+   *
+   * @param cls closure
+   * @param account_pub which account received a payment
+   * @param lifetime for how long is the account now paid (increment)
+   * @return transaction status
+   */
+  enum SYNC_DB_QueryStatus
+  (*increment_lifetime_TR)(void *cls,
+                           const struct SYNC_AccountPublicKey *account_pub,
+                           struct GNUNET_TIME_Relative lifetime);
 
 };
 #endif
diff --git a/src/syncdb/Makefile.am b/src/syncdb/Makefile.am
index 56db964..9b3d4b0 100644
--- a/src/syncdb/Makefile.am
+++ b/src/syncdb/Makefile.am
@@ -1,7 +1,7 @@
 # This Makefile.am is in the public domain
 AM_CPPFLAGS = -I$(top_srcdir)/src/include
 
-plugindir = $(libdir)/taler
+plugindir = $(libdir)/sync
 
 if HAVE_POSTGRESQL
 if HAVE_GNUNETPQ
@@ -27,11 +27,11 @@ libsyncdb_la_LIBADD = \
   -lgnunetutil
 libsyncdb_la_LDFLAGS = \
    $(POSTGRESQL_LDFLAGS) \
-   -version-info 2:0:0 \
+   -version-info 0:0:0 \
    -no-undefined
 
 libsync_plugin_db_postgres_la_SOURCES = \
-  plugin_sync_postgres.c
+  plugin_syncdb_postgres.c
 libsync_plugin_db_postgres_la_LIBADD = \
   $(LTLIBINTL)
 libsync_plugin_db_postgres_la_LDFLAGS = \
diff --git a/src/syncdb/plugin_sync_postgres.c b/src/syncdb/plugin_sync_postgres.c
index 4e63198..59df4d5 100644
--- a/src/syncdb/plugin_sync_postgres.c
+++ b/src/syncdb/plugin_sync_postgres.c
@@ -15,10 +15,8 @@
 */
 /**
  * @file sync/plugin_syncdb_postgres.c
- * @brief database helper functions for postgres used by the sync
- * @author Sree Harsha Totakura <sreeharsha@totakura.in>
+ * @brief database helper functions for postgres used by sync
  * @author Christian Grothoff
- * @author Marcello Stanisci
  */
 #include "platform.h"
 #include <gnunet/gnunet_util_lib.h>
@@ -28,12 +26,6 @@
 #include "sync_database_lib.h"
 
 /**
- * How often do we re-try if we run into a DB serialization error?
- */
-#define MAX_RETRIES 3
-
-
-/**
  * Type of the "cls" argument given to each of the functions in
  * our API.
  */
@@ -69,6 +61,7 @@ postgres_drop_tables (void *cls)
 {
   struct PostgresClosure *pg = cls;
   struct GNUNET_PQ_ExecuteStatement es[] = {
+    GNUNET_PQ_make_try_execute ("DROP TABLE IF EXISTS accounts CASCADE;"),
     GNUNET_PQ_make_try_execute ("DROP TABLE IF EXISTS backups;"),
     GNUNET_PQ_EXECUTE_STATEMENT_END
   };
@@ -125,6 +118,7 @@ postgres_preflight (void *cls)
   pg->transaction_name = NULL;
 }
 
+
 /**
  * Start a transaction.
  *
@@ -157,12 +151,13 @@ begin_transaction (void *cls,
   return GNUNET_OK;
 }
 
+
 /**
-* Roll back the current transaction of a database connection.
-*
-* @param cls the `struct PostgresClosure` with the plugin-specific state
-* @return #GNUNET_OK on success
-*/
+ * Roll back the current transaction of a database connection.
+ *
+ * @param cls the `struct PostgresClosure` with the plugin-specific state
+ * @return #GNUNET_OK on success
+ */
 static void
 rollback (void *cls)
 {
@@ -182,14 +177,14 @@ rollback (void *cls)
   pg->transaction_name = NULL;
 }
 
+
 /**
  * Commit the current transaction of a database connection.
  *
  * @param cls the `struct PostgresClosure` with the plugin-specific state
  * @return transaction status code
  */
-
-static enum SYNC_DB_QueryStatus
+static enum GNUNET_DB_QueryStatus
 commit_transaction (void *cls)
 {
   struct PostgresClosure *pg = cls;
@@ -206,6 +201,108 @@ commit_transaction (void *cls)
 }
 
 
+/**
+   * Function called to perform "garbage collection" on the
+   * database, expiring records we no longer require.  Deletes
+   * all user records that are not paid up (and by cascade deletes
+   * the associated recovery documents). Also deletes expired
+   * truth and financial records older than @a fin_expire.
+   *
+   * @param cls closure
+   * @param expire backups older than the given time stamp should be garbage collected
+   * @return transaction status
+   */
+static enum SYNC_DB_QueryStatus
+postgres_gc (void *cls,
+             struct GNUNET_TIME_Absolute expire)
+{
+}
+
+
+/**
+ * Store backup. Only applicable for the FIRST backup under
+ * an @a account_pub. Use @e update_backup_TR to update an
+ * existing backup.
+ *
+ * @param cls closure
+ * @param account_pub account to store @a backup under
+ * @param account_sig signature affirming storage request
+ * @param backup_hash hash of @a backup
+ * @param backup_size number of bytes in @a backup
+ * @param backup raw data to backup
+ * @return transaction status
+ */
+static enum SYNC_DB_QueryStatus
+postgres_store_backup (void *cls,
+                       const struct SYNC_AccountPublicKey *account_pub,
+                       const struct SYNC_AccountSignature *account_sig,
+                       const struct GNUNET_HashCode *backup_hash,
+                       size_t backup_size,
+                       const void *backup)
+{
+}
+
+
+/**
+ * Update backup.
+ *
+ * @param cls closure
+ * @param account_pub account to store @a backup under
+ * @param account_sig signature affirming storage request
+ * @param old_backup_hash hash of the previous backup (must match)
+ * @param backup_hash hash of @a backup
+ * @param backup_size number of bytes in @a backup
+ * @param backup raw data to backup
+ * @return transaction status
+ */
+static enum SYNC_DB_QueryStatus
+postgres_update_backup (void *cls,
+                        const struct SYNC_AccountPublicKey *account_pub,
+                        const struct GNUNET_HashCode *old_backup_hash,
+                        const struct SYNC_AccountSignature *account_sig,
+                        const struct GNUNET_HashCode *backup_hash,
+                        size_t backup_size,
+                        const void *backup)
+{
+}
+
+
+/**
+ * Obtain backup.
+ *
+ * @param cls closure
+ * @param account_pub account to store @a backup under
+ * @param account_sig[OUT] set to signature affirming storage request
+ * @param backup_hash[OUT] set to hash of @a backup
+ * @param backup_size[OUT] set to number of bytes in @a backup
+ * @param backup[OUT] set to raw data to backup, caller MUST FREE
+ */
+static enum SYNC_DB_QueryStatus
+postgres_lookup_backup (void *cls,
+                        const struct SYNC_AccountPublicKey *account_pub,
+                        struct SYNC_AccountSignature *account_sig,
+                        struct GNUNET_HashCode *backup_hash,
+                        size_t *backup_size,
+                        void **backup)
+{
+}
+
+
+/**
+ * Increment account lifetime.
+ *
+ * @param cls closure
+ * @param account_pub which account received a payment
+ * @param lifetime for how long is the account now paid (increment)
+ * @return transaction status
+ */
+static enum SYNC_DB_QueryStatus
+postgres_increment_lifetime (void *cls,
+                             const struct SYNC_AccountPublicKey *account_pub,
+                             struct GNUNET_TIME_Relative lifetime)
+{
+}
+
 
 /**
  * Initialize Postgres database subsystem.
@@ -223,19 +320,68 @@ libsync_plugin_db_postgres_init (void *cls)
     /* Orders created by the frontend, not signed or given a nonce yet.
        The contract terms will change (nonce will be added) when moved to the
        contract terms table */
+    GNUNET_PQ_make_execute ("CREATE TABLE IF NOT EXISTS accounts"
+                            "("
+                            "account_pub BYTEA PRIMARY KEY CHECK (length(account_pub)=32),"
+                            "expiration_date INT8 NOT NULL"
+                            ");"),
     GNUNET_PQ_make_execute ("CREATE TABLE IF NOT EXISTS backups"
-                            "("                            
-                            "data BYTEA NOT NULL,"
+                            "("
+                            "account_pub BYTEA PRIMARY KEY REFERENCES accounts (account_pub),"
+                            "account_sig BYTEA NOT NULL CHECK (length(account_sig)=64),"
+                            "backup_hash BYTEA NOT NULL CHECK (length(backup_hash)=64),"
+                            "data BYTEA NOT NULL"
                             ");"),
+    /* index for gc */
+    GNUNET_PQ_make_try_execute (
+      "CREATE INDEX accounts_expire ON "
+      "accounts (expiration_date);"),
     GNUNET_PQ_EXECUTE_STATEMENT_END
   };
   struct GNUNET_PQ_PreparedStatement ps[] = {
+    GNUNET_PQ_make_prepare ("account_insert",
+                            "INSERT INTO accounts "
+                            "("
+                            "account_pub,"
+                            "expiration_date"
+                            ") VALUES "
+                            "($1,$2);",
+                            2),
+    GNUNET_PQ_make_prepare ("account_update",
+                            "UPDATE accounts "
+                            "SET"
+                            " expiration_date=expiration_data+$1 "
+                            "WHERE"
+                            " account_pub=$2;",
+                            2),
+    GNUNET_PQ_make_prepare ("gc",
+                            "DELETE FROM accounts "
+                            "WHERE"
+                            " expiration_data<$1;",
+                            1),
     GNUNET_PQ_make_prepare ("backup_insert",
                             "INSERT INTO backups "
-                            "(data"
+                            "("
+                            "account_pub,"
+                            "account_sig,"
+                            "backup_hash,"
+                            "data"
                             ") VALUES "
-                            "($1);",
-                            1),
+                            "($1,$2,$3,$4);",
+                            4),
+    GNUNET_PQ_make_prepare ("backup_update",
+                            "UPDATE backups "
+                            " SET"
+                            " backup_hash=$1,"
+                            " account_sig=$2,"
+                            " data=$3"
+                            " WHERE"
+                            "   account_pub=$4"
+                            "  AND"
+                            "   backup_hash=$5"
+                            ") VALUES "
+                            "($1,$2,$3,$4,$5);",
+                            5),
     GNUNET_PQ_make_prepare ("do_commit",
                             "COMMIT",
                             0),
@@ -256,9 +402,10 @@ libsync_plugin_db_postgres_init (void *cls)
   plugin = GNUNET_new (struct SYNC_DatabasePlugin);
   plugin->cls = pg;
   plugin->drop_tables = &postgres_drop_tables;
-  plugin->preflight = &postgres_preflight;
-  plugin->rollback = &rollback;
-  plugin->commit = &commit_transaction;
+  plugin->gc = &postgres_gc;
+  plugin->store_backup_TR = &postgres_store_backup;
+  plugin->update_backup_TR = &postgres_update_backup;
+  plugin->increment_lifetime_TR = &postgres_increment_lifetime;
   return plugin;
 }
 
@@ -281,4 +428,5 @@ libsync_plugin_db_postgres_done (void *cls)
   return NULL;
 }
 
+
 /* end of plugin_syncdb_postgres.c */
diff --git a/src/syncdb/sync_db_plugin.c b/src/syncdb/sync_db_plugin.c
index 6b2c6e0..6c4f8d5 100644
--- a/src/syncdb/sync_db_plugin.c
+++ b/src/syncdb/sync_db_plugin.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2015, 2016 GNUnet e.V. and INRIA
+  Copyright (C) 2019 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Lesser General Public License as published by the Free Software
@@ -14,13 +14,13 @@
   TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
 */
 /**
- * @file merchantdb/merchantdb_plugin.c
+ * @file syncdb/sync_db_plugin.c
  * @brief Logic to load database plugin
  * @author Christian Grothoff
  * @author Sree Harsha Totakura <sreeharsha@totakura.in>
  */
 #include "platform.h"
-#include "anastasis_database_plugin.h"
+#include "sync_database_plugin.h"
 #include <ltdl.h>
 
 
@@ -30,27 +30,27 @@
  * @param cfg configuration to use
  * @return #GNUNET_OK on success
  */
-struct ANASTASIS_DatabasePlugin *
-ANASTASIS_DB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
+struct SYNC_DatabasePlugin *
+SYNC_DB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
 {
   char *plugin_name;
   char *lib_name;
   struct GNUNET_CONFIGURATION_Handle *cfg_dup;
-  struct ANASTASIS_DatabasePlugin *plugin;
+  struct SYNC_DatabasePlugin *plugin;
 
   if (GNUNET_SYSERR ==
       GNUNET_CONFIGURATION_get_value_string (cfg,
-                                             "anastasis",
+                                             "sync",
                                              "db",
                                              &plugin_name))
   {
     GNUNET_log_config_missing (GNUNET_ERROR_TYPE_ERROR,
-                               "anastasis",
+                               "sync",
                                "db");
     return NULL;
   }
   (void) GNUNET_asprintf (&lib_name,
-                          "libanastasis_plugin_db_%s",
+                          "libsync_plugin_db_%s",
                           plugin_name);
   GNUNET_free (plugin_name);
   cfg_dup = GNUNET_CONFIGURATION_dup (cfg);
@@ -70,7 +70,7 @@ ANASTASIS_DB_plugin_load (const struct GNUNET_CONFIGURATION_Handle *cfg)
  * @param plugin the plugin to unload
  */
 void
-ANASTASIS_DB_plugin_unload (struct ANASTASIS_DatabasePlugin *plugin)
+SYNC_DB_plugin_unload (struct SYNC_DatabasePlugin *plugin)
 {
   char *lib_name;
 
@@ -146,4 +146,4 @@ plugin_fini ()
 }
 
 
-/* end of anastasis_db_plugin.c */
+/* end of sync_db_plugin.c */
diff --git a/src/util/Makefile.am b/src/util/Makefile.am
new file mode 100644
index 0000000..bc1291c
--- /dev/null
+++ b/src/util/Makefile.am
@@ -0,0 +1,28 @@
+# This Makefile.am is in the public domain
+AM_CPPFLAGS = -I$(top_srcdir)/src/include $(LIBGCRYPT_CFLAGS)
+
+if USE_COVERAGE
+  AM_CFLAGS = --coverage -O0
+  XLIB = -lgcov
+endif
+
+
+pkgcfgdir = $(prefix)/share/sync/config.d/
+
+pkgcfg_DATA = \
+  paths.conf
+
+bin_SCRIPTS = \
+  sync-config
+
+lib_LTLIBRARIES = \
+  libsyncutil.la
+
+libsyncutil_la_SOURCES = \
+  os_installation.c
+libsyncutil_la_LIBADD = \
+  -lgnunetutil \
+  $(XLIB)
+libsyncutil_la_LDFLAGS = \
+  -version-info 0:0:0 \
+  -export-dynamic -no-undefined
diff --git a/src/util/os_installation.c b/src/util/os_installation.c
new file mode 100644
index 0000000..85092d1
--- /dev/null
+++ b/src/util/os_installation.c
@@ -0,0 +1,71 @@
+/*
+     This file is part of GNU Taler.
+     Copyright (C) 2019 Taler Systems SA
+
+     Sync 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; either version 3, or (at your
+     option) any later version.
+
+     Sync 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 Sync; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+     Boston, MA 02110-1301, USA.
+*/
+
+/**
+ * @file os_installation.c
+ * @brief initialize libgnunet OS subsystem for Sync.
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <gnunet/gnunet_util_lib.h>
+
+
+/**
+ * Default project data used for installation path detection
+ * for GNU Sync.
+ */
+static const struct GNUNET_OS_ProjectData sync_pd = {
+  .libname = "libsyncutil",
+  .project_dirname = "sync",
+  .binary_name = "sync-httpd",
+  .env_varname = "SYNC_PREFIX",
+  .base_config_varname = "SYNC_BASE_CONFIG",
+  .bug_email = "taler@lists.gnu.org",
+  .homepage = "http://www.gnu.org/s/taler/",
+  .config_file = "sync.conf",
+  .user_config_file = "~/.config/sync.conf",
+  .version = PACKAGE_VERSION,
+  .is_gnu = 1,
+  .gettext_domain = "sync",
+  .gettext_path = NULL,
+};
+
+
+/**
+ * Return default project data used by Sync.
+ */
+const struct GNUNET_OS_ProjectData *
+SYNC_project_data_default (void)
+{
+  return &sync_pd;
+}
+
+
+/**
+ * Initialize libsyncutil.
+ */
+void __attribute__ ((constructor))
+SYNC_OS_init ()
+{
+  GNUNET_OS_init (&sync_pd);
+}
+
+
+/* end of os_installation.c */
diff --git a/src/util/sync-config b/src/util/sync-config
new file mode 100644
index 0000000..6184167
--- /dev/null
+++ b/src/util/sync-config
@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+
+set -eu
+
+if ! type gnunet-config >/dev/null; then
+  echo "$0 needs gnunet-config to be installed"
+  exit 1
+fi
+
+# FIXME: not very portable ...
+# FIXME: should use "libdir" instead of prefix/lib, but somehow
+# the recursive expansion does not work ;-(.
+GC=`which gnunet-config`
+ASAN=""
+A=`ldd $GC | grep libasan` && ASAN=`echo $A | awk '{print $3 ":"}'`
+export LD_PRELOAD=${ASAN}${LD_PRELOAD:-}:/home/grothoff/lib/libsyncutil.so
+exec gnunet-config "$@"