incubator-nuttx/libs/libc/unistd/lib_setreuid.c

76 lines
2.6 KiB
C

/****************************************************************************
* libs/libc/unistd/lib_setreuid.c
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership. The
* ASF licenses this file to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <unistd.h>
#include <errno.h>
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: setreuid
*
* Description:
* The setreuid() function sets the real user ID and/or the effective user
* ID of the calling task group to ruid and/or euid.
*
* Input Parameters:
* ruid - Real user identity to set. The special value (uid_t)-1
* indicates that the real user ID should not be changed.
* ruid - Effective user identity to set. The special value (uid_t)-1
* indicates that the effective user ID should not be changed.
*
* Returned Value:
* Zero if successful and -1 in case of failure, in which case errno is set
* appropriately.
*
****************************************************************************/
int setreuid(uid_t ruid, uid_t euid)
{
int ret = OK;
if (ruid != (uid_t)-1)
{
/* Set the real user ID. CAREFUL: This exploits non-standard behavior
* of setuid(): setuid() should set the real, effective, and saved
* user ID. Here we depend on it setting only the real user ID.
*/
ret = setuid(ruid);
}
if (ret >= 0 && euid != (uid_t)-1)
{
/* Set the effective user ID */
ret = seteuid(euid);
}
return ret;
}