NetBSD/usr.bin/chpass/chpass.c

317 lines
7.0 KiB
C

/* $NetBSD: chpass.c,v 1.35 2011/08/31 16:24:57 plunky Exp $ */
/*-
* Copyright (c) 1988, 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. 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/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1988, 1993, 1994\
The Regents of the University of California. All rights reserved.");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)chpass.c 8.4 (Berkeley) 4/2/94";
#else
__RCSID("$NetBSD: chpass.c,v 1.35 2011/08/31 16:24:57 plunky Exp $");
#endif
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <util.h>
#include <libgen.h>
#include "chpass.h"
#include "pathnames.h"
static char tempname[] = "/tmp/pw.XXXXXX";
uid_t uid;
int use_yp;
void (*Pw_error)(const char *, int, int);
#ifdef YP
extern int _yp_check(char **); /* buried deep inside libc */
#endif
__dead static void baduser(void);
static void cleanup(void);
__dead static void usage(void);
int
main(int argc, char **argv)
{
enum { NEWSH, LOADENTRY, EDITENTRY } op;
struct passwd *pw, lpw, old_pw;
int ch, dfd, pfd, tfd;
#ifdef YP
int yflag = 0;
#endif
char *arg, *username = NULL;
#ifdef __GNUC__
pw = NULL; /* XXX gcc -Wuninitialized */
arg = NULL;
#endif
#ifdef YP
use_yp = _yp_check(NULL);
#endif
op = EDITENTRY;
while ((ch = getopt(argc, argv, "a:s:ly")) != -1)
switch (ch) {
case 'a':
op = LOADENTRY;
arg = optarg;
break;
case 's':
op = NEWSH;
arg = optarg;
break;
case 'l':
use_yp = 0;
break;
case 'y':
#ifdef YP
if (!use_yp)
errx(1, "YP not in use.");
yflag = 1;
#else
errx(1, "YP support not compiled in.");
#endif
break;
default:
usage();
}
argc -= optind;
argv += optind;
uid = getuid();
switch (argc) {
case 0:
/* nothing */
break;
case 1:
username = argv[0];
break;
default:
usage();
}
#ifdef YP
/*
* We need to determine if we _really_ want to use YP.
* If we defaulted to YP (i.e. were not given the -y flag),
* and the master is not running rpc.yppasswdd, we check
* to see if the user exists in the local passwd database.
* If so, we use it, otherwise we error out.
*/
if (use_yp && yflag == 0) {
if (check_yppasswdd()) {
/*
* We weren't able to contact rpc.yppasswdd.
* Check to see if we're in the local
* password database. If we are, use it.
*/
if (username != NULL)
pw = getpwnam(username);
else
pw = getpwuid(uid);
if (pw != NULL)
use_yp = 0;
else {
warnx("master YP server not running yppasswd"
" daemon.");
errx(1, "Can't change password.");
}
}
}
#endif
#ifdef YP
if (use_yp)
Pw_error = yppw_error;
else
#endif
Pw_error = pw_error;
#ifdef YP
if (op == LOADENTRY && use_yp)
errx(1, "cannot load entry using YP.\n"
"\tUse the -l flag to load local.");
#endif
if (op == EDITENTRY || op == NEWSH) {
if (username != NULL) {
pw = getpwnam(username);
if (pw == NULL)
errx(1, "unknown user: %s", username);
if (uid && uid != pw->pw_uid)
baduser();
} else {
pw = getpwuid(uid);
if (pw == NULL)
errx(1, "unknown user: uid %u", uid);
}
/* Make a copy for later verification */
old_pw = *pw;
old_pw.pw_gecos = strdup(old_pw.pw_gecos);
if (!old_pw.pw_gecos) {
err(1, "strdup");
/*NOTREACHED*/
}
}
if (op == NEWSH) {
/* protect p_shell -- it thinks NULL is /bin/sh */
if (!arg[0])
usage();
if (p_shell(arg, pw, NULL))
(*Pw_error)(NULL, 0, 1);
}
if (op == LOADENTRY) {
if (uid)
baduser();
pw = &lpw;
if (!pw_scan(arg, pw, NULL))
exit(1);
}
/* Edit the user passwd information if requested. */
if (op == EDITENTRY) {
struct stat sb;
dfd = mkstemp(tempname);
if (dfd < 0 || fcntl(dfd, F_SETFD, 1) < 0)
(*Pw_error)(tempname, 1, 1);
if (atexit(cleanup)) {
cleanup();
errx(1, "couldn't register cleanup");
}
if (stat(dirname(tempname), &sb) == -1)
err(1, "couldn't stat `%s'", dirname(tempname));
if (!(sb.st_mode & S_ISTXT))
errx(1, "temporary directory `%s' is not sticky",
dirname(tempname));
display(tempname, dfd, pw);
edit(tempname, pw);
}
#ifdef YP
if (use_yp) {
if (pw_yp(pw, uid))
yppw_error(NULL, 0, 1);
else
exit(0);
/* Will not exit from this if. */
}
#endif /* YP */
/*
* Get the passwd lock file and open the passwd file for
* reading.
*/
pw_init();
tfd = pw_lock(0);
if (tfd < 0) {
if (errno != EEXIST)
err(1, "%s", _PATH_MASTERPASSWD_LOCK);
warnx("The passwd file is busy, waiting...");
tfd = pw_lock(10);
if (tfd < 0) {
if (errno != EEXIST)
err(1, "%s", _PATH_MASTERPASSWD_LOCK);
errx(1, "The passwd file is still busy, "
"try again later.");
}
}
if (fcntl(tfd, F_SETFD, 1) < 0)
pw_error(_PATH_MASTERPASSWD_LOCK, 1, 1);
pfd = open(_PATH_MASTERPASSWD, O_RDONLY, 0);
if (pfd < 0 || fcntl(pfd, F_SETFD, 1) < 0)
pw_error(_PATH_MASTERPASSWD, 1, 1);
/* Copy the passwd file to the lock file, updating pw. */
pw_copy(pfd, tfd, pw, (op == LOADENTRY) ? NULL : &old_pw);
close(pfd);
close(tfd);
/* Now finish the passwd file update. */
if (pw_mkdb(username, 0) < 0)
pw_error(NULL, 0, 1);
exit(0);
}
static void
baduser(void)
{
errx(1, "%s", strerror(EACCES));
}
static void
usage(void)
{
(void)fprintf(stderr,
"usage: %s [-a list] [-s shell] [-l] [user]\n"
" %s [-a list] [-s shell] [-y] [user]\n",
getprogname(), getprogname());
exit(1);
}
static void
cleanup(void)
{
(void)unlink(tempname);
}