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/* $OpenBSD: isexec.c,v 1.11 2017/10/27 16:47:08 mpi Exp $ */ |
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/* |
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* Copyright (c) 1983 Regents of the University of California. |
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* All rights reserved. |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* 1. Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* 2. Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in the |
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* documentation and/or other materials provided with the distribution. |
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* 3. Neither the name of the University nor the names of its contributors |
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* may be used to endorse or promote products derived from this software |
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* without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND |
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE |
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
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* SUCH DAMAGE. |
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*/ |
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#include <sys/types.h> |
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#include <elf.h> |
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#include <fcntl.h> |
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#include <unistd.h> |
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#include "client.h" |
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/* |
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* Determine whether 'file' is a binary executable or not. |
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*/ |
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int |
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isexec(char *file, struct stat *statp) |
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{ |
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Elf32_Ehdr hdr; |
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int fd, r; |
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/* |
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* Must be a regular file that has some executable mode bit on |
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*/ |
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if (!S_ISREG(statp->st_mode) || |
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!(statp->st_mode & (S_IXUSR|S_IXGRP|S_IXOTH))) |
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return(FALSE); |
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if ((fd = open(file, O_RDONLY, 0)) < 0) |
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return(FALSE); |
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r = read(fd, &hdr, sizeof(hdr)) == sizeof(hdr) && |
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IS_ELF(hdr) && hdr.e_type == ET_EXEC; |
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close(fd); |
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return (r); |
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} |