freebsd-skq/usr.bin/chpass/pw_copy.c
cjc ed673bb689 It was possible for an unprivileged user to tie up the password
information (no one else can vipw(8), chpass(1), or even passwd(1)),
either on purpose or by accident, until an administrator manually
intervened. Instead, do not lock the master.passwd file while a user
is editing his information. But once we go to write the new
information, check that the modified user's information has not
changed in the password database since we started. Abort the changes
if it has.

Add a $FreeBSD$ to pw_copy.h.

PR:		i386/35816
Obtained from:	NetBSD
MFC after:	1 week
2002-03-18 02:22:53 +00:00

178 lines
5.4 KiB
C

/*-
* Copyright (c) 1990, 1993, 1994
* The 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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.
*
* $FreeBSD$
*/
#ifndef lint
static const char sccsid[] = "@(#)pw_copy.c 8.4 (Berkeley) 4/2/94";
#endif /* not lint */
/*
* This module is used to copy the master password file, replacing a single
* record, by chpass(1) and passwd(1).
*/
#include <err.h>
#include <pwd.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <pw_scan.h>
#include <pw_util.h>
#include "pw_copy.h"
extern char *tempname;
/* for use in pw_copy(). Compare a pw entry to a pw struct. */
static int
pw_equal(char *buf, struct passwd *pw)
{
struct passwd buf_pw;
int len;
len = strlen (buf);
if (buf[len-1] == '\n')
buf[len-1] = '\0';
if (!__pw_scan(buf, &buf_pw, _PWSCAN_MASTER))
return 0;
return (strcmp(pw->pw_name, buf_pw.pw_name) == 0
&& pw->pw_uid == buf_pw.pw_uid
&& pw->pw_gid == buf_pw.pw_gid
&& strcmp(pw->pw_class, buf_pw.pw_class) == 0
&& (long)pw->pw_change == (long)buf_pw.pw_change
&& (long)pw->pw_expire == (long)buf_pw.pw_expire
&& strcmp(pw->pw_gecos, buf_pw.pw_gecos) == 0
&& strcmp(pw->pw_dir, buf_pw.pw_dir) == 0
&& strcmp(pw->pw_shell, buf_pw.pw_shell) == 0);
}
void
pw_copy(ffd, tfd, pw, old_pw)
int ffd, tfd;
struct passwd *pw, *old_pw;
{
FILE *from, *to;
int done;
char *p, buf[8192];
char uidstr[20];
char gidstr[20];
char chgstr[20];
char expstr[20];
snprintf(uidstr, sizeof(uidstr), "%lu", (unsigned long)pw->pw_uid);
snprintf(gidstr, sizeof(gidstr), "%lu", (unsigned long)pw->pw_gid);
snprintf(chgstr, sizeof(chgstr), "%ld", (long)pw->pw_change);
snprintf(expstr, sizeof(expstr), "%ld", (long)pw->pw_expire);
if (!(from = fdopen(ffd, "r")))
pw_error(_PATH_MASTERPASSWD, 1, 1);
if (!(to = fdopen(tfd, "w")))
pw_error(tempname, 1, 1);
for (done = 0; fgets(buf, sizeof(buf), from);) {
if (!strchr(buf, '\n')) {
warnx("%s: line too long", _PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
}
if (done) {
(void)fprintf(to, "%s", buf);
if (ferror(to))
goto err;
continue;
}
for (p = buf; *p != '\n'; p++)
if (*p != ' ' && *p != '\t')
break;
if (*p == '#' || *p == '\n') {
(void)fprintf(to, "%s", buf);
if (ferror(to))
goto err;
continue;
}
if (!(p = strchr(buf, ':'))) {
warnx("%s: corrupted entry", _PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
}
*p = '\0';
if (strcmp(buf, pw->pw_name)) {
*p = ':';
(void)fprintf(to, "%s", buf);
if (ferror(to))
goto err;
continue;
}
*p = ':';
if (old_pw && !pw_equal(buf, old_pw)) {
warnx("%s: entry for %s has changed",
_PATH_MASTERPASSWD, pw->pw_name);
pw_error(NULL, 0, 1);
}
(void)fprintf(to, "%s:%s:%s:%s:%s:%s:%s:%s:%s:%s\n",
pw->pw_name, pw->pw_passwd,
pw->pw_fields & _PWF_UID ? uidstr : "",
pw->pw_fields & _PWF_GID ? gidstr : "",
pw->pw_class,
pw->pw_fields & _PWF_CHANGE ? chgstr : "",
pw->pw_fields & _PWF_EXPIRE ? expstr : "",
pw->pw_gecos, pw->pw_dir, pw->pw_shell);
done = 1;
if (ferror(to))
goto err;
}
if (!done) {
#ifdef YP
/* Ultra paranoid: shouldn't happen. */
if (getuid()) {
warnx("%s: not found in %s -- permission denied",
pw->pw_name, _PATH_MASTERPASSWD);
pw_error(NULL, 0, 1);
} else
#endif /* YP */
(void)fprintf(to, "%s:%s:%s:%s:%s:%s:%s:%s:%s:%s\n",
pw->pw_name, pw->pw_passwd,
pw->pw_fields & _PWF_UID ? uidstr : "",
pw->pw_fields & _PWF_GID ? gidstr : "",
pw->pw_class,
pw->pw_fields & _PWF_CHANGE ? chgstr : "",
pw->pw_fields & _PWF_EXPIRE ? expstr : "",
pw->pw_gecos, pw->pw_dir, pw->pw_shell);
}
if (ferror(to))
err: pw_error(NULL, 1, 1);
(void)fclose(to);
}