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

91 lines
3.4 KiB
C

/****************************************************************************
* libs/libc/unistd/lib_setreuid.c
*
* Copyright (C) 2019 Gregory Nutt. All rights reserved.
* Author: Michael Jung <mijung@gmx.net>
*
* 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 NuttX 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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.
*
****************************************************************************/
/****************************************************************************
* 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;
}