New HDB backend MDB

From 25fbcef63298790e594c3ae09ec510f9dbdcf85e Mon Sep 17 00:00:00 2001
From: Howard Chu <[email protected]>
Date: Tue, 6 Dec 2011 17:35:08 -0800
Subject: [PATCH] Add support for OpenLDAP libmdb

---
 cf/db.m4            |   14 ++
 lib/hdb/Makefile.am |    1 +
 lib/hdb/hdb-mdb.c   |  369 +++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 384 insertions(+), 0 deletions(-)
 create mode 100644 lib/hdb/hdb-mdb.c

diff --git a/cf/db.m4 b/cf/db.m4
index ff10f76..5c9460f 100644
--- a/cf/db.m4
+++ b/cf/db.m4
@@ -22,6 +22,11 @@ AC_ARG_ENABLE(ndbm-db,
                                       [if you don't want ndbm db]),[
 ])
 
+AC_ARG_ENABLE(mdb-db,
+                       AS_HELP_STRING([--disable-mdb-db],
+                                      [if you don't want OpenLDAP libmdb db]),[
+])
+
 have_ndbm=no
 db_type=unknown
 
@@ -120,6 +125,14 @@ dnl test for ndbm compatability
 
 ]) # fi berkeley db
 
+if test "$enable_mdb_db" != "no"; then
+  if test "$db_type" = "unknown"; then
+    AC_CHECK_HEADER(mdb.h, [
+		AC_CHECK_LIB(mdb, mdb_env_create, db_type=mdb; DBLIB="-lmdb"
+		AC_DEFINE(HAVE_MDB, 1, [define if you have the OpenLDAP mdb library]))])
+  fi
+fi
+
 if test "$enable_ndbm_db" != "no"; then
 
   if test "$db_type" = "unknown" -o "$ac_cv_func_dbm_firstkey" = ""; then
@@ -215,6 +228,7 @@ fi
 
 AM_CONDITIONAL(HAVE_DB1, test "$db_type" = db1)dnl
 AM_CONDITIONAL(HAVE_DB3, test "$db_type" = db3)dnl
+AM_CONDITIONAL(HAVE_MDB, test "$db_type" = mdb)dnl
 AM_CONDITIONAL(HAVE_NDBM, test "$db_type" = ndbm)dnl
 AM_CONDITIONAL(HAVE_DBHEADER, test "$dbheader" != "")dnl
 
diff --git a/lib/hdb/Makefile.am b/lib/hdb/Makefile.am
index 9c7ea1f..0a677e8 100644
--- a/lib/hdb/Makefile.am
+++ b/lib/hdb/Makefile.am
@@ -83,6 +83,7 @@ dist_libhdb_la_SOURCES =			\
 	hdb.c					\
 	hdb-sqlite.c				\
 	hdb-keytab.c				\
+	hdb-mdb.c				\
 	hdb-mitdb.c				\
 	hdb_locl.h				\
 	hdb-private.h				\
diff --git a/lib/hdb/hdb-mdb.c b/lib/hdb/hdb-mdb.c
new file mode 100644
index 0000000..91f0083
--- /dev/null
+++ b/lib/hdb/hdb-mdb.c
@@ -0,0 +1,369 @@
+/*
+ * Copyright (c) 1997 - 2006 Kungliga Tekniska Högskolan
+ * (Royal Institute of Technology, Stockholm, Sweden).
+ * Copyright (c) 2011 - Howard Chu, Symas Corp.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include "hdb_locl.h"
+
+#if HAVE_MDB
+
+#include <mdb.h>
+
+typedef struct mdb_info {
+    MDB_env *e;
+    MDB_txn *t;
+    MDB_dbi d;
+    MDB_cursor *c;
+} mdb_info;
+
+static krb5_error_code
+DB_close(krb5_context context, HDB *db)
+{
+    mdb_info *mi = (mdb_info *)db->hdb_db;
+
+    mdb_cursor_close(mi->c);
+    mdb_txn_abort(mi->t);
+    mdb_env_close(mi->e);
+    mi->c = 0;
+    mi->t = 0;
+    mi->e = 0;
+    return 0;
+}
+
+static krb5_error_code
+DB_destroy(krb5_context context, HDB *db)
+{
+    krb5_error_code ret;
+
+    ret = hdb_clear_master_key (context, db);
+    free(db->hdb_name);
+    free(db->hdb_db);
+    free(db);
+    return ret;
+}
+
+static krb5_error_code
+DB_lock(krb5_context context, HDB *db, int operation)
+{
+    db->lock_count++;
+    return 0;
+}
+
+static krb5_error_code
+DB_unlock(krb5_context context, HDB *db)
+{
+    if (db->lock_count > 1) {
+	db->lock_count--;
+	return 0;
+    }
+    heim_assert(db->lock_count == 1, "HDB lock/unlock sequence does not match");
+    db->lock_count--;
+    return 0;
+}
+
+
+static krb5_error_code
+DB_seq(krb5_context context, HDB *db,
+       unsigned flags, hdb_entry_ex *entry, int flag)
+{
+    mdb_info *mi = db->hdb_db;
+    MDB_val key, value;
+    krb5_data key_data, data;
+    int code;
+
+    key.mv_size = 0;
+    value.mv_size = 0;
+    code = mdb_cursor_get(mi->c, &key, &value, flag);
+    if (code == MDB_NOTFOUND)
+	return HDB_ERR_NOENTRY;
+    if (code)
+	return code;
+
+    key_data.data = key.mv_data;
+    key_data.length = key.mv_size;
+    data.data = value.mv_data;
+    data.length = value.mv_size;
+    memset(entry, 0, sizeof(*entry));
+    if (hdb_value2entry(context, &data, &entry->entry))
+	return DB_seq(context, db, flags, entry, MDB_NEXT);
+    if (db->hdb_master_key_set && (flags & HDB_F_DECRYPT)) {
+	code = hdb_unseal_keys (context, db, &entry->entry);
+	if (code)
+	    hdb_free_entry (context, entry);
+    }
+    if (entry->entry.principal == NULL) {
+	entry->entry.principal = malloc(sizeof(*entry->entry.principal));
+	if (entry->entry.principal == NULL) {
+	    hdb_free_entry (context, entry);
+	    krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	    return ENOMEM;
+	} else {
+	    hdb_key2principal(context, &key_data, entry->entry.principal);
+	}
+    }
+    return 0;
+}
+
+
+static krb5_error_code
+DB_firstkey(krb5_context context, HDB *db, unsigned flags, hdb_entry_ex *entry)
+{
+    mdb_info *mi = db->hdb_db;
+    int code;
+
+    /* Always start with a fresh cursor to pick up latest DB state */
+    if (mi->t)
+    	mdb_txn_abort(mi->t);
+
+    code = mdb_txn_begin(mi->e, NULL, MDB_RDONLY, &mi->t);
+    if (code)
+    	return code;
+
+    code = mdb_cursor_open(mi->t, mi->d, &mi->c);
+    if (code)
+    	return code;
+
+    return DB_seq(context, db, flags, entry, MDB_FIRST);
+}
+
+
+static krb5_error_code
+DB_nextkey(krb5_context context, HDB *db, unsigned flags, hdb_entry_ex *entry)
+{
+    return DB_seq(context, db, flags, entry, MDB_NEXT);
+}
+
+static krb5_error_code
+DB_rename(krb5_context context, HDB *db, const char *new_name)
+{
+    int ret;
+    char *old, *new;
+
+    if (asprintf(&old, "%s.mdb", db->hdb_name) == -1)
+		return ENOMEM;
+    if (asprintf(&new, "%s.mdb", new_name) == -1) {
+		free(old);
+		return ENOMEM;
+	}
+    ret = rename(old, new);
+    free(old);
+    free(new);
+    if(ret)
+	return errno;
+
+    free(db->hdb_name);
+    db->hdb_name = strdup(new_name);
+    return 0;
+}
+
+static krb5_error_code
+DB__get(krb5_context context, HDB *db, krb5_data key, krb5_data *reply)
+{
+    mdb_info *mi = (mdb_info*)db->hdb_db;
+    MDB_txn *txn;
+    MDB_val k, v;
+    int code;
+
+    k.mv_data = key.data;
+    k.mv_size = key.length;
+
+    code = mdb_txn_begin(mi->e, NULL, MDB_RDONLY, &txn);
+    if (code)
+    	return code;
+
+    code = mdb_get(txn, mi->d, &k, &v);
+    if (code == 0)
+	krb5_data_copy(reply, v.mv_data, v.mv_size);
+    mdb_txn_abort(txn);
+    if(code == MDB_NOTFOUND)
+	return HDB_ERR_NOENTRY;
+    return code;
+}
+
+static krb5_error_code
+DB__put(krb5_context context, HDB *db, int replace,
+	krb5_data key, krb5_data value)
+{
+    mdb_info *mi = (mdb_info*)db->hdb_db;
+    MDB_txn *txn;
+    MDB_val k, v;
+    int code;
+
+    k.mv_data = key.data;
+    k.mv_size = key.length;
+    v.mv_data = value.data;
+    v.mv_size = value.length;
+
+    code = mdb_txn_begin(mi->e, NULL, 0, &txn);
+    if (code)
+    	return code;
+
+    code = mdb_put(txn, mi->d, &k, &v, replace ? 0 : MDB_NOOVERWRITE);
+    if (code)
+    	mdb_txn_abort(txn);
+    else
+    	code = mdb_txn_commit(txn);
+    if(code == MDB_KEYEXIST)
+	return HDB_ERR_EXISTS;
+    return code;
+}
+
+static krb5_error_code
+DB__del(krb5_context context, HDB *db, krb5_data key)
+{
+    mdb_info *mi = (mdb_info*)db->hdb_db;
+    MDB_txn *txn;
+    MDB_val k;
+    krb5_error_code code;
+
+    k.mv_data = key.data;
+    k.mv_size = key.length;
+
+    code = mdb_txn_begin(mi->e, NULL, 0, &txn);
+    if (code)
+    	return code;
+
+    code = mdb_del(txn, mi->d, &k, NULL);
+    if (code)
+    	mdb_txn_abort(txn);
+    else
+    	code = mdb_txn_commit(txn);
+    if(code == MDB_NOTFOUND)
+	return HDB_ERR_NOENTRY;
+    return code;
+}
+
+static krb5_error_code
+DB_open(krb5_context context, HDB *db, int flags, mode_t mode)
+{
+    mdb_info *mi = (mdb_info *)db->hdb_db;
+    MDB_txn *txn;
+    char *fn;
+    krb5_error_code ret;
+    int myflags = MDB_NOSUBDIR;
+
+    if((flags & O_ACCMODE) == O_RDONLY)
+      myflags |= MDB_RDONLY;
+
+    if (asprintf(&fn, "%s.mdb", db->hdb_name) == -1) {
+	krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	return ENOMEM;
+    }
+    if (mdb_env_create(&mi->e)) {
+	free(fn);
+	krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	return ENOMEM;
+    }
+    
+    ret = mdb_env_open(mi->e, fn, myflags, mode);
+    if (ret) {
+fail:
+	mdb_env_close(mi->e);
+	mi->e = 0;
+	free(fn);
+	krb5_set_error_message(context, ret, "opening %s: %s",
+			      db->hdb_name, mdb_strerror(ret));
+	return ret;
+    }
+    free(fn);
+
+    ret = mdb_txn_begin(mi->e, NULL, MDB_RDONLY, &txn);
+    if (ret)
+    	goto fail;
+
+    ret = mdb_open(txn, NULL, 0, &mi->d);
+    mdb_txn_abort(txn);
+    if (ret)
+    	goto fail;
+
+    if((flags & O_ACCMODE) == O_RDONLY)
+	ret = hdb_check_db_format(context, db);
+    else
+	ret = hdb_init_db(context, db);
+    if(ret == HDB_ERR_NOENTRY)
+	return 0;
+    if (ret) {
+	DB_close(context, db);
+	krb5_set_error_message(context, ret, "hdb_open: failed %s database %s",
+			       (flags & O_ACCMODE) == O_RDONLY ?
+			       "checking format of" : "initialize",
+			       db->hdb_name);
+    }
+
+    return ret;
+}
+
+krb5_error_code
+hdb_db_create(krb5_context context, HDB **db,
+	      const char *filename)
+{
+    *db = calloc(1, sizeof(**db));
+    if (*db == NULL) {
+	krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	return ENOMEM;
+    }
+
+    (*db)->hdb_db = calloc(1, sizeof(mdb_info));
+    if ((*db)->hdb_db == NULL) {
+	free(*db);
+	*db = NULL;
+	krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	return ENOMEM;
+    }
+    (*db)->hdb_name = strdup(filename);
+    if ((*db)->hdb_name == NULL) {
+    	free((*db)->hdb_db);
+	free(*db);
+	*db = NULL;
+	krb5_set_error_message(context, ENOMEM, "malloc: out of memory");
+	return ENOMEM;
+    }
+    (*db)->hdb_master_key_set = 0;
+    (*db)->hdb_openp = 0;
+    (*db)->hdb_capability_flags = HDB_CAP_F_HANDLE_ENTERPRISE_PRINCIPAL;
+    (*db)->hdb_open  = DB_open;
+    (*db)->hdb_close = DB_close;
+    (*db)->hdb_fetch_kvno = _hdb_fetch_kvno;
+    (*db)->hdb_store = _hdb_store;
+    (*db)->hdb_remove = _hdb_remove;
+    (*db)->hdb_firstkey = DB_firstkey;
+    (*db)->hdb_nextkey= DB_nextkey;
+    (*db)->hdb_lock = DB_lock;
+    (*db)->hdb_unlock = DB_unlock;
+    (*db)->hdb_rename = DB_rename;
+    (*db)->hdb__get = DB__get;
+    (*db)->hdb__put = DB__put;
+    (*db)->hdb__del = DB__del;
+    (*db)->hdb_destroy = DB_destroy;
+    return 0;
+}
+#endif /* HAVE_MDB */
-- 
1.7.1