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/* $OpenBSD: isexec.c,v 1.13 2021/10/24 21:24:17 deraadt Exp $ */
/*
* Copyright (c) 1983 Regents of the University of California.
* 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 University 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 REGENTS 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 REGENTS 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 <sys/types.h>
#include <elf.h>
#include <fcntl.h>
#include <unistd.h>
#include "client.h"
/*
* Determine whether 'file' is a binary executable or not.
*/
int
isexec(char *file, struct stat *statp)
{
Elf32_Ehdr hdr;
int fd, r;
/*
* Must be a regular file that has some executable mode bit on
*/
if (!S_ISREG(statp->st_mode) ||
!(statp->st_mode & (S_IXUSR|S_IXGRP|S_IXOTH)))
return(FALSE);
if ((fd = open(file, O_RDONLY)) == -1)
return(FALSE);
r = read(fd, &hdr, sizeof(hdr)) == sizeof(hdr) &&
IS_ELF(hdr) && hdr.e_type == ET_EXEC;
close(fd);
return (r);
}
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