OpenSolaris_b135/ucbcmd/vipw/vipw.c
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (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 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
/* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/* All Rights Reserved */
/*
* Portions of this source code were derived from Berkeley 4.3 BSD
* under license from the Regents of the University of California.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/fcntl.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <stdlib.h>
#include <strings.h>
/*
* Password file editor with locking.
*/
#define DEFAULT_EDITOR "/usr/bin/vi"
static int copyfile(char *, char *);
static int editfile(char *, char *, char *, time_t *);
static int sanity_check(char *, time_t *, char *);
static int validsh(char *);
char *ptemp = "/etc/ptmp";
char *stemp = "/etc/stmp";
char *passwd = "/etc/passwd";
char *shadow = "/etc/shadow";
char buf[BUFSIZ];
int
main(void)
{
int fd;
FILE *ft, *fp;
char *editor;
int ok = 0;
time_t o_mtime, n_mtime;
struct stat osbuf, sbuf, oshdbuf, shdbuf;
char c;
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGHUP, SIG_IGN);
setbuf(stderr, (char *)NULL);
editor = getenv("VISUAL");
if (editor == 0)
editor = getenv("EDITOR");
if (editor == 0)
editor = DEFAULT_EDITOR;
(void)umask(0077);
if (stat(passwd, &osbuf) < 0) {
(void)fprintf(stderr,"vipw: can't stat passwd file.\n");
goto bad;
}
if (copyfile(passwd, ptemp))
goto bad;
if (stat(ptemp, &sbuf) < 0) {
(void)fprintf(stderr,
"vipw: can't stat ptemp file, %s unchanged\n",
passwd);
goto bad;
}
o_mtime = sbuf.st_mtime;
if (editfile(editor, ptemp, passwd, &n_mtime)) {
if (sanity_check(ptemp, &n_mtime, passwd))
goto bad;
if (o_mtime >= n_mtime)
goto bad;
}
ok++;
if (o_mtime < n_mtime) {
fprintf(stdout, "\nYou have modified the password file.\n");
fprintf(stdout,
"Press 'e' to edit the shadow file for consistency,\n 'q' to quit: ");
if ((c = getchar()) == 'q') {
if (chmod(ptemp, (osbuf.st_mode & 0644)) < 0) {
(void) fprintf(stderr, "vipw: %s: ", ptemp);
perror("chmod");
goto bad;
}
if (rename(ptemp, passwd) < 0) {
(void) fprintf(stderr, "vipw: %s: ", ptemp);
perror("rename");
goto bad;
}
if (((osbuf.st_gid != sbuf.st_gid) ||
(osbuf.st_uid != sbuf.st_uid)) &&
(chown(passwd, osbuf.st_uid, osbuf.st_gid) < 0)) {
(void) fprintf(stderr, "vipw: %s ", ptemp);
perror("chown");
}
goto bad;
} else if (c == 'e') {
if (stat(shadow, &oshdbuf) < 0) {
(void) fprintf(stderr,
"vipw: can't stat shadow file.\n");
goto bad;
}
if (copyfile(shadow, stemp))
goto bad;
if (stat(stemp, &shdbuf) < 0) {
(void) fprintf(stderr,
"vipw: can't stat stmp file.\n");
goto bad;
}
if (editfile(editor, stemp, shadow, &o_mtime))
goto bad;
ok++;
if (chmod(ptemp, (osbuf.st_mode & 0644)) < 0) {
(void) fprintf(stderr, "vipw: %s: ", ptemp);
perror("chmod");
goto bad;
}
if (chmod(stemp, (oshdbuf.st_mode & 0400)) < 0) {
(void) fprintf(stderr, "vipw: %s: ", stemp);
perror("chmod");
goto bad;
}
if (rename(ptemp, passwd) < 0) {
(void) fprintf(stderr, "vipw: %s: ", ptemp);
perror("rename");
goto bad;
}
if (((osbuf.st_gid != sbuf.st_gid) ||
(osbuf.st_uid != sbuf.st_uid)) &&
(chown(passwd, osbuf.st_uid, osbuf.st_gid) < 0)) {
(void) fprintf(stderr, "vipw: %s ", ptemp);
perror("chown");
}
if (rename(stemp, shadow) < 0) {
(void) fprintf(stderr, "vipw: %s: ", stemp);
perror("rename");
goto bad;
} else if (((oshdbuf.st_gid != shdbuf.st_gid) ||
(oshdbuf.st_uid != shdbuf.st_uid)) &&
(chown(shadow, oshdbuf.st_uid, oshdbuf.st_gid) < 0)) {
(void) fprintf(stderr, "vipw: %s ", stemp);
perror("chown");
}
}
}
bad:
(void) unlink(ptemp);
(void) unlink(stemp);
return (ok ? 0 : 1);
/* NOTREACHED */
}
int
copyfile(char *from, char *to)
{
int fd;
FILE *fp, *ft;
fd = open(to, O_WRONLY|O_CREAT|O_EXCL, 0600);
if (fd < 0) {
if (errno == EEXIST) {
(void) fprintf(stderr, "vipw: %s file busy\n", from);
exit(1);
}
(void) fprintf(stderr, "vipw: "); perror(to);
exit(1);
}
ft = fdopen(fd, "w");
if (ft == NULL) {
(void) fprintf(stderr, "vipw: "); perror(to);
return( 1 );
}
fp = fopen(from, "r");
if (fp == NULL) {
(void) fprintf(stderr, "vipw: "); perror(from);
return( 1 );
}
while (fgets(buf, sizeof (buf) - 1, fp) != NULL)
fputs(buf, ft);
(void) fclose(ft);
(void) fclose(fp);
return( 0 );
}
int
editfile(char *editor, char *temp, char *orig, time_t *mtime)
{
(void)sprintf(buf, "%s %s", editor, temp);
if (system(buf) == 0) {
return (sanity_check(temp, mtime, orig));
}
return(1);
}
int
validsh(char *rootsh)
{
char *sh, *getusershell();
int ret = 0;
setusershell();
while((sh = getusershell()) != NULL ) {
if( strcmp( rootsh, sh) == 0 ) {
ret = 1;
break;
}
}
endusershell();
return(ret);
}
/*
* sanity checks
* return 0 if ok, 1 otherwise
*/
int
sanity_check(char *temp, time_t *mtime, char *orig)
{
int i, ok = 0;
FILE *ft;
struct stat sbuf, statbuf;
char *ldir;
int isshadow = 0;
if (!strcmp(orig, shadow))
isshadow = 1;
/* sanity checks */
if (stat(temp, &sbuf) < 0) {
(void)fprintf(stderr,
"vipw: can't stat %s file, %s unchanged\n",
temp, orig);
return(1);
}
*mtime = sbuf.st_mtime;
if (sbuf.st_size == 0) {
(void)fprintf(stderr, "vipw: bad %s file, %s unchanged\n",
temp, orig);
return(1);
}
ft = fopen(temp, "r");
if (ft == NULL) {
(void)fprintf(stderr,
"vipw: can't reopen %s file, %s unchanged\n",
temp, orig);
return(1);
}
while (fgets(buf, sizeof (buf) - 1, ft) != NULL) {
char *cp;
cp = index(buf, '\n');
if (cp == 0)
continue; /* ??? allow very long lines
* and passwd files that do
* not end in '\n' ???
*/
*cp = '\0';
cp = index(buf, ':');
if (cp == 0) /* lines without colon
* separated fields
*/
continue;
*cp = '\0';
if (strcmp(buf, "root"))
continue;
/* root password */
*cp = ':';
cp = index(cp + 1, ':');
if (cp == 0)
goto bad_root;
/* root uid for password */
if (!isshadow)
if (atoi(cp + 1) != 0) {
(void)fprintf(stderr, "root UID != 0:\n%s\n",
buf);
break;
}
/* root uid for passwd and sp_lstchg for shadow */
cp = index(cp + 1, ':');
if (cp == 0)
goto bad_root;
/* root's gid for passwd and sp_min for shadow*/
cp = index(cp + 1, ':');
if (cp == 0)
goto bad_root;
/* root's gecos for passwd and sp_max for shadow*/
cp = index(cp + 1, ':');
if (isshadow) {
for (i=0; i<3; i++)
if ((cp = index(cp + 1, ':')) == 0)
goto bad_root;
} else {
if (cp == 0) {
bad_root: (void)fprintf(stderr,
"Missing fields in root entry:\n%s\n", buf);
break;
}
}
if (!isshadow) {
/* root's login directory */
ldir = ++cp;
cp = index(cp, ':');
if (cp == 0)
goto bad_root;
*cp = '\0';
if (stat(ldir, &statbuf) < 0) {
*cp = ':';
(void) fprintf(stderr,
"root login dir doesn't exist:\n%s\n",
buf);
break;
} else if (!S_ISDIR(statbuf.st_mode)) {
*cp = ':';
(void) fprintf(stderr,
"root login dir is not a directory:\n%s\n",
buf);
break;
}
*cp = ':';
/* root's login shell */
++cp;
if (*cp && ! validsh(cp)) {
(void)fprintf(stderr,
"Invalid root shell:\n%s\n", buf);
break;
}
}
ok++;
}
(void)fclose(ft);
if (ok)
return(0);
else {
(void)fprintf(stderr,
"vipw: you mangled the %s file, %s unchanged\n",
temp, orig);
return(1);
}
}