freebsd-skq/usr.bin/chpass/edit.c
Mike Barcroft f458f48b02 Prevent chpass(1) from writing -1 in the UID or GID fields
in the password file by properly casting integers.

PR:		27757
Reviewed by:	des
Approved by:	des
MFC after:	4 days
2001-07-26 23:27:10 +00:00

271 lines
7.4 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[] = "@(#)edit.c 8.3 (Berkeley) 4/2/94";
#endif /* not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <md5.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <pw_scan.h>
#include <pw_util.h>
#include "chpass.h"
#ifdef YP
#include "pw_yp.h"
#endif /* YP */
extern char *tempname;
void
edit(pw)
struct passwd *pw;
{
struct stat begin, end;
char *begin_sum, *end_sum;
for (;;) {
if (stat(tempname, &begin))
pw_error(tempname, 1, 1);
begin_sum = MD5File(tempname, (char *)NULL);
pw_edit(1);
if (stat(tempname, &end))
pw_error(tempname, 1, 1);
end_sum = MD5File(tempname, (char *)NULL);
if ((begin.st_mtime == end.st_mtime) &&
(strcmp(begin_sum, end_sum) == 0)) {
warnx("no changes made");
pw_error(NULL, 0, 0);
}
free(begin_sum);
free(end_sum);
if (verify(pw))
break;
pw_prompt();
}
}
/*
* display --
* print out the file for the user to edit; strange side-effect:
* set conditional flag if the user gets to edit the shell.
*/
void
display(fd, pw)
int fd;
struct passwd *pw;
{
FILE *fp;
char *bp, *p, *ttoa();
if (!(fp = fdopen(fd, "w")))
pw_error(tempname, 1, 1);
(void)fprintf(fp,
#ifdef YP
"#Changing %s information for %s.\n", _use_yp ? "NIS" : "user database", pw->pw_name);
if (!uid && (!_use_yp || suser_override)) {
#else
"#Changing user database information for %s.\n", pw->pw_name);
if (!uid) {
#endif /* YP */
(void)fprintf(fp, "Login: %s\n", pw->pw_name);
(void)fprintf(fp, "Password: %s\n", pw->pw_passwd);
(void)fprintf(fp, "Uid [#]: %lu\n", (unsigned long)pw->pw_uid);
(void)fprintf(fp, "Gid [# or name]: %lu\n",
(unsigned long)pw->pw_gid);
(void)fprintf(fp, "Change [month day year]: %s\n",
ttoa(pw->pw_change));
(void)fprintf(fp, "Expire [month day year]: %s\n",
ttoa(pw->pw_expire));
(void)fprintf(fp, "Class: %s\n", pw->pw_class);
(void)fprintf(fp, "Home directory: %s\n", pw->pw_dir);
(void)fprintf(fp, "Shell: %s\n",
*pw->pw_shell ? pw->pw_shell : _PATH_BSHELL);
}
/* Only admin can change "restricted" shells. */
#if 0
else if (ok_shell(pw->pw_shell))
/*
* Make shell a restricted field. Ugly with a
* necklace, but there's not much else to do.
*/
#else
else if ((!list[E_SHELL].restricted && ok_shell(pw->pw_shell)) || !uid)
/*
* If change not restrict (table.c) and standard shell
* OR if root, then allow editing of shell.
*/
#endif
(void)fprintf(fp, "Shell: %s\n",
*pw->pw_shell ? pw->pw_shell : _PATH_BSHELL);
else
list[E_SHELL].restricted = 1;
bp = pw->pw_gecos;
p = strsep(&bp, ",");
p = strdup(p ? p : "");
list[E_NAME].save = p;
if (!list[E_NAME].restricted || !uid)
(void)fprintf(fp, "Full Name: %s\n", p);
p = strsep(&bp, ",");
p = strdup(p ? p : "");
list[E_LOCATE].save = p;
if (!list[E_LOCATE].restricted || !uid)
(void)fprintf(fp, "Office Location: %s\n", p);
p = strsep(&bp, ",");
p = strdup(p ? p : "");
list[E_BPHONE].save = p;
if (!list[E_BPHONE].restricted || !uid)
(void)fprintf(fp, "Office Phone: %s\n", p);
p = strsep(&bp, ",");
p = strdup(p ? p : "");
list[E_HPHONE].save = p;
if (!list[E_HPHONE].restricted || !uid)
(void)fprintf(fp, "Home Phone: %s\n", p);
bp = strdup(bp ? bp : "");
list[E_OTHER].save = bp;
if (!list[E_OTHER].restricted || !uid)
(void)fprintf(fp, "Other information: %s\n", bp);
(void)fchown(fd, getuid(), getgid());
(void)fclose(fp);
}
int
verify(pw)
struct passwd *pw;
{
ENTRY *ep;
char *p;
struct stat sb;
FILE *fp;
int len, line;
static char buf[LINE_MAX];
if (!(fp = fopen(tempname, "r")))
pw_error(tempname, 1, 1);
if (fstat(fileno(fp), &sb))
pw_error(tempname, 1, 1);
if (sb.st_size == 0) {
warnx("corrupted temporary file");
goto bad;
}
line = 0;
while (fgets(buf, sizeof(buf), fp)) {
line++;
if (!buf[0] || buf[0] == '#')
continue;
if (!(p = strchr(buf, '\n'))) {
warnx("line %d too long", line);
goto bad;
}
*p = '\0';
for (ep = list;; ++ep) {
if (!ep->prompt) {
warnx("unrecognized field on line %d", line);
goto bad;
}
if (!strncasecmp(buf, ep->prompt, ep->len)) {
if (ep->restricted && uid) {
warnx(
"you may not change the %s field",
ep->prompt);
goto bad;
}
if (!(p = strchr(buf, ':'))) {
warnx("line %d corrupted", line);
goto bad;
}
while (isspace(*++p));
if (ep->except && strpbrk(p, ep->except)) {
warnx(
"illegal character in the \"%s\" field",
ep->prompt);
goto bad;
}
if ((ep->func)(p, pw, ep)) {
bad: (void)fclose(fp);
return (0);
}
break;
}
}
}
(void)fclose(fp);
/* Build the gecos field. */
len = strlen(list[E_NAME].save) + strlen(list[E_BPHONE].save) +
strlen(list[E_HPHONE].save) + strlen(list[E_LOCATE].save) +
strlen(list[E_OTHER].save) + 5;
if (!(p = malloc(len)))
err(1, NULL);
(void)sprintf(pw->pw_gecos = p, "%s,%s,%s,%s,%s", list[E_NAME].save,
list[E_LOCATE].save, list[E_BPHONE].save, list[E_HPHONE].save,
list[E_OTHER].save);
while ((len = strlen(pw->pw_gecos)) && pw->pw_gecos[len - 1] == ',')
pw->pw_gecos[len - 1] = '\0';
if (snprintf(buf, sizeof(buf),
"%s:%s:%lu:%lu:%s:%ld:%ld:%s:%s:%s",
pw->pw_name, pw->pw_passwd, (unsigned long)pw->pw_uid,
(unsigned long)pw->pw_gid, pw->pw_class, (long)pw->pw_change,
(long)pw->pw_expire, pw->pw_gecos, pw->pw_dir,
pw->pw_shell) >= sizeof(buf)) {
warnx("entries too long");
free(p);
return (0);
}
free(p);
return (__pw_scan(buf, pw, _PWSCAN_WARN|_PWSCAN_MASTER));
}