71 lines
1.4 KiB
C
71 lines
1.4 KiB
C
/*++
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/* NAME
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/* open_as 3
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/* SUMMARY
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/* open file as user
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/* SYNOPSIS
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/* #include <fcntl.h>
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/* #include <open_as.h>
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/*
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/* int open_as(path, flags, mode, euid, egid)
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/* const char *path;
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/* int mode;
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/* uid_t euid;
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/* gid_t egid;
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/* DESCRIPTION
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/* open_as() opens the named \fIpath\fR with the named \fIflags\fR
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/* and \fImode\fR, and with the effective rights specified by \fIeuid\fR
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/* and \fIegid\fR. A -1 result means the open failed.
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/* DIAGNOSTICS
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/* Fatal error: no permission to change privilege level.
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/* SEE ALSO
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/* set_eugid(3) switch effective rights
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/* LICENSE
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/* .ad
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/* .fi
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/* The Secure Mailer license must be distributed with this software.
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/* AUTHOR(S)
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/* Wietse Venema
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/* IBM T.J. Watson Research
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/* P.O. Box 704
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/* Yorktown Heights, NY 10598, USA
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/*--*/
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/* System library. */
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#include <sys_defs.h>
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#include <fcntl.h>
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#include <unistd.h>
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/* Utility library. */
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#include "msg.h"
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#include "set_eugid.h"
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#include "open_as.h"
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/* open_as - open file as user */
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int open_as(const char *path, int flags, int mode, uid_t euid, gid_t egid)
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{
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uid_t saved_euid = geteuid();
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gid_t saved_egid = getegid();
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int fd;
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/*
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* Switch to the target user privileges.
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*/
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set_eugid(euid, egid);
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/*
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* Open that file.
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*/
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fd = open(path, flags, mode);
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/*
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* Restore saved privileges.
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*/
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set_eugid(saved_euid, saved_egid);
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return (fd);
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}
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