/*
 * Copyright (c) 1997 - 2001 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden). 
 * 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"

RCSID("$Id: db3.c,v 1.8.6.1 2003/08/29 16:59:39 lha Exp $");

#if HAVE_DB3

#ifdef HAVE_DB4_DB_H
#include <db4/db.h>
#elif defined(HAVE_DB3_DB_H)
#include <db3/db.h>
#else
#include <db.h>
#endif

static krb5_error_code
DB_close(krb5_context context, HDB *db)
{
    DB *d = (DB*)db->db;
    DBC *dbcp = (DBC*)db->dbc;

    dbcp->c_close(dbcp);
    db->dbc = 0;
    d->close(d, 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->name);
    free(db);
    return ret;
}

static krb5_error_code
DB_lock(krb5_context context, HDB *db, int operation)
{
    DB *d = (DB*)db->db;
    int fd;
    if ((*d->fd)(d, &fd))
	return HDB_ERR_CANT_LOCK_DB;
    return hdb_lock(fd, operation);
}

static krb5_error_code
DB_unlock(krb5_context context, HDB *db)
{
    DB *d = (DB*)db->db;
    int fd;
    if ((*d->fd)(d, &fd))
	return HDB_ERR_CANT_LOCK_DB;
    return hdb_unlock(fd);
}


static krb5_error_code
DB_seq(krb5_context context, HDB *db,
       unsigned flags, hdb_entry *entry, int flag)
{
    DBT key, value;
    DBC *dbcp = db->dbc;
    krb5_data key_data, data;
    int code;

    memset(&key, 0, sizeof(DBT));
    memset(&value, 0, sizeof(DBT));
    if (db->lock(context, db, HDB_RLOCK))
	return HDB_ERR_DB_INUSE;
    code = dbcp->c_get(dbcp, &key, &value, flag);
    db->unlock(context, db); /* XXX check value */
    if (code == DB_NOTFOUND)
	return HDB_ERR_NOENTRY;
    if (code)
	return code;

    key_data.data = key.data;
    key_data.length = key.size;
    data.data = value.data;
    data.length = value.size;
    if (hdb_value2entry(context, &data, entry))
	return DB_seq(context, db, flags, entry, DB_NEXT);
    if (db->master_key_set && (flags & HDB_F_DECRYPT)) {
	code = hdb_unseal_keys (context, db, entry);
	if (code)
	    hdb_free_entry (context, entry);
    }
    if (entry->principal == NULL) {
	entry->principal = malloc(sizeof(*entry->principal));
	if (entry->principal == NULL) {
	    hdb_free_entry (context, entry);
	    krb5_set_error_string(context, "malloc: out of memory");
	    return ENOMEM;
	} else {
	    hdb_key2principal(context, &key_data, entry->principal);
	}
    }
    return 0;
}


static krb5_error_code
DB_firstkey(krb5_context context, HDB *db, unsigned flags, hdb_entry *entry)
{
    return DB_seq(context, db, flags, entry, DB_FIRST);
}


static krb5_error_code
DB_nextkey(krb5_context context, HDB *db, unsigned flags, hdb_entry *entry)
{
    return DB_seq(context, db, flags, entry, DB_NEXT);
}

static krb5_error_code
DB_rename(krb5_context context, HDB *db, const char *new_name)
{
    int ret;
    char *old, *new;

    asprintf(&old, "%s.db", db->name);
    asprintf(&new, "%s.db", new_name);
    ret = rename(old, new);
    free(old);
    free(new);
    if(ret)
	return errno;
    
    free(db->name);
    db->name = strdup(new_name);
    return 0;
}

static krb5_error_code
DB__get(krb5_context context, HDB *db, krb5_data key, krb5_data *reply)
{
    DB *d = (DB*)db->db;
    DBT k, v;
    int code;

    memset(&k, 0, sizeof(DBT));
    memset(&v, 0, sizeof(DBT));
    k.data = key.data;
    k.size = key.length;
    k.flags = 0;
    if ((code = db->lock(context, db, HDB_RLOCK)))
	return code;
    code = d->get(d, NULL, &k, &v, 0);
    db->unlock(context, db);
    if(code == DB_NOTFOUND)
	return HDB_ERR_NOENTRY;
    if(code)
	return code;

    krb5_data_copy(reply, v.data, v.size);
    return 0;
}

static krb5_error_code
DB__put(krb5_context context, HDB *db, int replace, 
	krb5_data key, krb5_data value)
{
    DB *d = (DB*)db->db;
    DBT k, v;
    int code;

    memset(&k, 0, sizeof(DBT));
    memset(&v, 0, sizeof(DBT));
    k.data = key.data;
    k.size = key.length;
    k.flags = 0;
    v.data = value.data;
    v.size = value.length;
    v.flags = 0;
    if ((code = db->lock(context, db, HDB_WLOCK)))
	return code;
    code = d->put(d, NULL, &k, &v, replace ? 0 : DB_NOOVERWRITE);
    db->unlock(context, db);
    if(code == DB_KEYEXIST)
	return HDB_ERR_EXISTS;
    if(code)
	return errno;
    return 0;
}

static krb5_error_code
DB__del(krb5_context context, HDB *db, krb5_data key)
{
    DB *d = (DB*)db->db;
    DBT k;
    krb5_error_code code;
    memset(&k, 0, sizeof(DBT));
    k.data = key.data;
    k.size = key.length;
    k.flags = 0;
    code = db->lock(context, db, HDB_WLOCK);
    if(code)
	return code;
    code = d->del(d, NULL, &k, 0);
    db->unlock(context, db);
    if(code == DB_NOTFOUND)
	return HDB_ERR_NOENTRY;
    if(code)
	return code;
    return 0;
}

static krb5_error_code
DB_open(krb5_context context, HDB *db, int flags, mode_t mode)
{
    char *fn;
    krb5_error_code ret;
    DB *d;
    int myflags = 0;

    if (flags & O_CREAT)
      myflags |= DB_CREATE;

    if (flags & O_EXCL)
      myflags |= DB_EXCL;

    if (flags & O_RDONLY)
      myflags |= DB_RDONLY;

    if (flags & O_TRUNC)
      myflags |= DB_TRUNCATE;

    asprintf(&fn, "%s.db", db->name);
    if (fn == NULL) {
	krb5_set_error_string(context, "malloc: out of memory");
	return ENOMEM;
    }
    db_create(&d, NULL, 0);
    db->db = d;
#if (DB_VERSION_MAJOR > 3) && (DB_VERSION_MINOR > 0)
    if ((ret = d->open(db->db, NULL, fn, NULL, DB_BTREE, myflags, mode))) {
#else
    if ((ret = d->open(db->db, fn, NULL, DB_BTREE, myflags, mode))) {
#endif
      if(ret == ENOENT)
	/* try to open without .db extension */
#if (DB_VERSION_MAJOR > 3) && (DB_VERSION_MINOR > 0)
	if (d->open(db->db, NULL, db->name, NULL, DB_BTREE, myflags, mode)) {
#else
	if (d->open(db->db, db->name, NULL, DB_BTREE, myflags, mode)) {
#endif
	  free(fn);
	  krb5_set_error_string(context, "opening %s: %s",
				db->name, strerror(ret));
	  return ret;
	}
    }
    free(fn);

    ret = d->cursor(d, NULL, (DBC **)&db->dbc, 0);
    if (ret) {
	krb5_set_error_string(context, "d->cursor: %s", strerror(ret));
        return ret;
    }

    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;
    return ret;
}

krb5_error_code
hdb_db_create(krb5_context context, HDB **db, 
	      const char *filename)
{
    *db = malloc(sizeof(**db));
    if (*db == NULL) {
	krb5_set_error_string(context, "malloc: out of memory");
	return ENOMEM;
    }

    (*db)->db = NULL;
    (*db)->name = strdup(filename);
    if ((*db)->name == NULL) {
	krb5_set_error_string(context, "malloc: out of memory");
	free(*db);
	*db = NULL;
	return ENOMEM;
    }
    (*db)->master_key_set = 0;
    (*db)->openp = 0;
    (*db)->open  = DB_open;
    (*db)->close = DB_close;
    (*db)->fetch = _hdb_fetch;
    (*db)->store = _hdb_store;
    (*db)->remove = _hdb_remove;
    (*db)->firstkey = DB_firstkey;
    (*db)->nextkey= DB_nextkey;
    (*db)->lock = DB_lock;
    (*db)->unlock = DB_unlock;
    (*db)->rename = DB_rename;
    (*db)->_get = DB__get;
    (*db)->_put = DB__put;
    (*db)->_del = DB__del;
    (*db)->destroy = DB_destroy;
    return 0;
}
#endif /* HAVE_DB3 */