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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 1995 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
#include "mail.h"
/*
If mail file does not exist create it
*/
#ifdef OLD
void createmf(uid, file)
uid_t uid;
char *file;
{
int fd;
void (*istat)(), (*qstat)(), (*hstat)();
if (access(file, A_EXIST) == CERROR) {
istat = signal(SIGINT, SIG_IGN);
qstat = signal(SIGQUIT, SIG_IGN);
hstat = signal(SIGHUP, SIG_IGN);
umask(0);
if ((fd = creat(file, MFMODE)) == -1)
sav_errno = errno;
else
close(fd);
umask(7);
(void) signal(SIGINT, istat);
(void) signal(SIGQUIT, qstat);
(void) signal(SIGHUP, hstat);
}
}
#else
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
int accessmf(path)
char *path;
{
struct stat fsb,sb;
int mbfd;
tryagain:
if (lstat(path, &sb)) {
/* file/symlink does not exist, so create one */
mbfd = open(path,
O_APPEND|O_CREAT|O_EXCL|O_WRONLY, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
chmod(path, 0660);
/* if someone create a symlink/file just ahead */
/* of us, the create will failed with EEXIST */
/* This is what we want, because we do not */
/* want someone to re-direct our "create" */
/* request to a another location. */
if (mbfd == -1) {
if (errno == EEXIST)
goto tryagain;
}
/* file/symlink exist, make sure it is not linked */
} else if (sb.st_nlink != 1 || S_ISLNK(sb.st_mode)) {
fprintf(stderr,
"%s: security violation, '%s' should not be linked to other file\n", program, path);
sav_errno = errno;
return -1;
} else {
/* if we get here, there is a pre-existing file, */
/* and it is not a symlink... */
/* open it, and make sure it is the same file */
/* we lstat() before... */
/* this is to guard against someone deleting the */
/* old file and creat a new symlink in its place */
/* We are not createing a new file here, but we */
/* do not want append to the worng file either */
mbfd = open(path, O_APPEND|O_WRONLY, 0);
if (mbfd != -1 &&
(fstat(mbfd, &fsb) || fsb.st_nlink != 1 ||
S_ISLNK(fsb.st_mode) || sb.st_dev != fsb.st_dev ||
sb.st_ino != fsb.st_ino)) {
/* file changed after open */
fprintf(stderr, "%s: security violation, '%s' inode changed after open\n", program, path);
(void)close(mbfd);
return -1;
}
}
if (mbfd == -1) {
sav_errno = errno;
return -1;
}
return mbfd;
}
#endif
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