/*
* Copyright (c) 1987 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.
*
* Updated Thu Oct 12 09:56:55 1995 by faith@cs.unc.edu with security
* patches from Zefram <A.Main@dcs.warwick.ac.uk>
*
* Updated Thu Nov 9 21:58:53 1995 by Martin Schulze
* <joey@finlandia.infodrom.north.de>. Support for vigr.
*
* Martin Schulze's patches adapted to Util-Linux by Nicolai Langfeldt.
*
* 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
* - added Native Language Support
* Sun Mar 21 1999 - Arnaldo Carvalho de Melo <acme@conectiva.com.br>
* - fixed strerr(errno) in gettext calls
*/
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/file.h>
#include <sys/param.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include "c.h"
#include "nls.h"
#include "setpwnam.h"
#include "strutils.h"
#ifdef HAVE_LIBSELINUX
# include <selinux/selinux.h>
#endif
#define FILENAMELEN 67
enum {
VIPW,
VIGR
};
int program;
char orig_file[FILENAMELEN]; /* original file /etc/passwd or /etc/group */
char tmp_file[FILENAMELEN]; /* tmp file */
char tmptmp_file[FILENAMELEN]; /* very tmp file */
void pw_error __P((char *, int, int));
static void copyfile(int from, int to)
{
int nr, nw, off;
char buf[8 * 1024];
while ((nr = read(from, buf, sizeof(buf))) > 0)
for (off = 0; off < nr; nr -= nw, off += nw)
if ((nw = write(to, buf + off, nr)) < 0)
pw_error(tmp_file, 1, 1);
if (nr < 0)
pw_error(orig_file, 1, 1);
}
static void pw_init(void)
{
struct rlimit rlim;
/* Unlimited resource limits. */
rlim.rlim_cur = rlim.rlim_max = RLIM_INFINITY;
(void)setrlimit(RLIMIT_CPU, &rlim);
(void)setrlimit(RLIMIT_FSIZE, &rlim);
(void)setrlimit(RLIMIT_STACK, &rlim);
(void)setrlimit(RLIMIT_DATA, &rlim);
(void)setrlimit(RLIMIT_RSS, &rlim);
/* Don't drop core (not really necessary, but GP's). */
rlim.rlim_cur = rlim.rlim_max = 0;
(void)setrlimit(RLIMIT_CORE, &rlim);
/* Turn off signals. */
(void)signal(SIGALRM, SIG_IGN);
(void)signal(SIGHUP, SIG_IGN);
(void)signal(SIGINT, SIG_IGN);
(void)signal(SIGPIPE, SIG_IGN);
(void)signal(SIGQUIT, SIG_IGN);
(void)signal(SIGTERM, SIG_IGN);
(void)signal(SIGTSTP, SIG_IGN);
(void)signal(SIGTTOU, SIG_IGN);
/* Create with exact permissions. */
(void)umask(0);
}
static int pw_lock(void)
{
int lockfd, fd, ret;
/*
* If the password file doesn't exist, the system is hosed. Might as
* well try to build one. Set the close-on-exec bit so that users
* can't get at the encrypted passwords while editing. Open should
* allow flock'ing the file; see 4.4BSD. XXX
*/
#if 0
/* flock()ing is superfluous here, with the ptmp/ptmptmp system. */
if (flock(lockfd, LOCK_EX | LOCK_NB)) {
if (program == VIPW)
err(EXIT_FAILURE, _("cannot lock password file"));
else
err(EXIT_FAILURE, _("cannot lock group file"));
}
#endif
if ((fd = open(tmptmp_file, O_WRONLY | O_CREAT, 0600)) == -1)
err(EXIT_FAILURE, _("%s: open failed"), tmptmp_file);
ret = link(tmptmp_file, tmp_file);
(void)unlink(tmptmp_file);
if (ret == -1) {
if (errno == EEXIST)
errx(EXIT_FAILURE,
_("the %s file is busy (%s present)"),
program == VIPW ? "password" : "group", tmp_file);
else
err(EXIT_FAILURE, _("can't link %s"), tmp_file);
}
lockfd = open(orig_file, O_RDONLY, 0);
if (lockfd < 0) {
warn("%s", orig_file);
unlink(tmp_file);
exit(EXIT_FAILURE);
}
copyfile(lockfd, fd);
(void)close(lockfd);
(void)close(fd);
return 1;
}
static void pw_unlock(void)
{
char tmp[FILENAMELEN + 4];
sprintf(tmp, "%s%s", orig_file, ".OLD");
unlink(tmp);
if (link(orig_file, tmp))
warn(_("%s: create a link to %s failed"), orig_file, tmp);
#ifdef HAVE_LIBSELINUX
if (is_selinux_enabled() > 0) {
security_context_t passwd_context = NULL;
int ret = 0;
if (getfilecon(orig_file, &passwd_context) < 0) {
warnx(_("Can't get context for %s"), orig_file);
pw_error(orig_file, 1, 1);
}
ret = setfilecon(tmp_file, passwd_context);
freecon(passwd_context);
if (ret != 0) {
warnx(_("Can't set context for %s"), tmp_file);
pw_error(tmp_file, 1, 1);
}
}
#endif
if (rename(tmp_file, orig_file) == -1) {
int errsv = errno;
errx(EXIT_FAILURE,
("can't unlock %s: %s (your changes are still in %s)"),
orig_file, strerror(errsv), tmp_file);
}
unlink(tmp_file);
}
static void pw_edit(int notsetuid)
{
int pstat;
pid_t pid;
char *p, *editor;
if (!(editor = getenv("EDITOR")))
editor = strdup(_PATH_VI); /* adia@egnatia.ee.auth.gr */
if ((p = strrchr(strtok(editor, " \t"), '/')) != NULL)
++p;
else
p = editor;
pid = fork();
if (pid < 0)
err(EXIT_FAILURE, _("fork failed"));
if (!pid) {
if (notsetuid) {
(void)setgid(getgid());
(void)setuid(getuid());
}
execlp(editor, p, tmp_file, NULL);
/* Shouldn't get here */
_exit(EXIT_FAILURE);
}
for (;;) {
pid = waitpid(pid, &pstat, WUNTRACED);
if (WIFSTOPPED(pstat)) {
/* the editor suspended, so suspend us as well */
kill(getpid(), SIGSTOP);
kill(pid, SIGCONT);
} else {
break;
}
}
if (pid == -1 || !WIFEXITED(pstat) || WEXITSTATUS(pstat) != 0)
pw_error(editor, 1, 1);
}
void pw_error(char *name, int err, int eval)
{
if (err) {
if (name)
warn("%s: ", name);
else
warn(NULL);
}
warnx(_("%s unchanged"), orig_file);
unlink(tmp_file);
exit(eval);
}
static void edit_file(int is_shadow)
{
struct stat begin, end;
pw_init();
pw_lock();
if (stat(tmp_file, &begin))
pw_error(tmp_file, 1, 1);
pw_edit(0);
if (stat(tmp_file, &end))
pw_error(tmp_file, 1, 1);
if (begin.st_mtime == end.st_mtime) {
warnx(_("no changes made"));
pw_error((char *)NULL, 0, 0);
}
/* see pw_lock() where we create the file with mode 600 */
if (!is_shadow)
chmod(tmp_file, 0644);
else
chmod(tmp_file, 0400);
pw_unlock();
}
int main(int argc, char *argv[])
{
setlocale(LC_ALL, "");
bindtextdomain(PACKAGE, LOCALEDIR);
textdomain(PACKAGE);
memset(tmp_file, '\0', FILENAMELEN);
if (!strcmp(program_invocation_short_name, "vigr")) {
program = VIGR;
xstrncpy(orig_file, GROUP_FILE, sizeof(orig_file));
xstrncpy(tmp_file, GTMP_FILE, sizeof(tmp_file));
xstrncpy(tmptmp_file, GTMPTMP_FILE, sizeof(tmptmp_file));
} else {
program = VIPW;
xstrncpy(orig_file, PASSWD_FILE, sizeof(orig_file));
xstrncpy(tmp_file, PTMP_FILE, sizeof(tmp_file));
xstrncpy(tmptmp_file, PTMPTMP_FILE, sizeof(tmptmp_file));
}
if ((argc > 1) &&
(!strcmp(argv[1], "-V") || !strcmp(argv[1], "--version"))) {
printf(UTIL_LINUX_VERSION);
exit(EXIT_SUCCESS);
}
edit_file(0);
if (program == VIGR) {
strncpy(orig_file, SGROUP_FILE, FILENAMELEN - 1);
strncpy(tmp_file, SGTMP_FILE, FILENAMELEN - 1);
strncpy(tmptmp_file, SGTMPTMP_FILE, FILENAMELEN - 1);
} else {
strncpy(orig_file, SHADOW_FILE, FILENAMELEN - 1);
strncpy(tmp_file, SPTMP_FILE, FILENAMELEN - 1);
strncpy(tmptmp_file, SPTMPTMP_FILE, FILENAMELEN - 1);
}
if (access(orig_file, F_OK) == 0) {
char response[80];
printf((program == VIGR)
? _("You are using shadow groups on this system.\n")
: _("You are using shadow passwords on this system.\n"));
printf(_("Would you like to edit %s now [y/n]? "), orig_file);
/* EOF means no */
if (fgets(response, sizeof(response), stdin)) {
if (response[0] == 'y' || response[0] == 'Y')
edit_file(1);
}
}
exit(EXIT_SUCCESS);
}
