shadow/src/vipw.c

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/*
vipw, vigr edit the password or group file
with -s will edit shadow or gshadow file
Copyright (c) 1997 , Guy Maor <maor@ece.utexas.edu>
Copyright (c) 1999 - 2000, Marek Michałkiewicz
Copyright (c) 2002 - 2006, Tomasz Kłoczko
Copyright (c) 2007 - 2008, Nicolas François
All rights reserved.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
#include <config.h>
#ident "$Id$"
#include <errno.h>
#include <getopt.h>
#ifdef WITH_SELINUX
#include <selinux/selinux.h>
#endif /* WITH_SELINUX */
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <utime.h>
#include "defines.h"
#include "groupio.h"
#include "nscd.h"
#include "prototypes.h"
#include "pwio.h"
#include "sgroupio.h"
#include "shadowio.h"
/*@-exitarg@*/
#include "exitcodes.h"
#ifdef WITH_TCB
#include <tcb.h>
#include "tcbfuncs.h"
#endif /* WITH_TCB */
#define MSG_WARN_EDIT_OTHER_FILE _( \
"You have modified %s.\n"\
"You may need to modify %s for consistency.\n"\
"Please use the command '%s' to do so.\n")
/*
* Global variables
*/
static const char *progname, *filename, *fileeditname;
static bool filelocked = false;
static bool createedit = false;
static int (*unlock) (void);
static bool quiet = false;
#ifdef WITH_TCB
static const char *user = NULL;
static bool tcb_mode = false;
#define SHADOWTCB_SCRATCHDIR ":tmp"
#endif /* WITH_TCB */
/* local function prototypes */
static void usage (int status);
static int create_backup_file (FILE *, const char *, struct stat *);
static void vipwexit (const char *msg, int syserr, int ret);
static void vipwedit (const char *, int (*)(void), int (*)(void));
/*
* usage - display usage message and exit
*/
static void usage (int status)
{
(void)
fputs (_("Usage: vipw [options]\n"
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"\n"
"Options:\n"
" -g, --group edit group database\n"
" -h, --help display this help message and exit\n"
" -p, --passwd edit passwd database\n"
" -q, --quiet quiet mode\n"
" -s, --shadow edit shadow or gshadow database\n"
#ifdef WITH_TCB
" -u, --user which user's tcb shadow file to edit\n"
#endif /* WITH_TCB */
"\n"), (E_SUCCESS != status) ? stderr : stdout);
exit (status);
}
/*
*
*/
static int create_backup_file (FILE * fp, const char *backup, struct stat *sb)
{
struct utimbuf ub;
FILE *bkfp;
int c;
mode_t mask;
mask = umask (077);
bkfp = fopen (backup, "w");
(void) umask (mask);
if (NULL == bkfp) {
return -1;
}
c = 0;
if (fseeko (fp, 0, SEEK_SET) == 0)
while ((c = getc (fp)) != EOF) {
if (putc (c, bkfp) == EOF) {
break;
}
}
if ((EOF != c) || (ferror (fp) != 0) || (fflush (bkfp) != 0)) {
fclose (bkfp);
unlink (backup);
return -1;
}
if (fsync (fileno (bkfp)) != 0) {
(void) fclose (bkfp);
unlink (backup);
return -1;
}
if (fclose (bkfp) != 0) {
unlink (backup);
return -1;
}
ub.actime = sb->st_atime;
ub.modtime = sb->st_mtime;
if ( (utime (backup, &ub) != 0)
|| (chmod (backup, sb->st_mode) != 0)
|| (chown (backup, sb->st_uid, sb->st_gid) != 0)) {
unlink (backup);
return -1;
}
return 0;
}
/*
*
*/
static void vipwexit (const char *msg, int syserr, int ret)
{
int err = errno;
if (createedit) {
if (unlink (fileeditname) != 0) {
fprintf (stderr, _("%s: failed to remove %s\n"), progname, fileeditname);
/* continue */
}
}
if (filelocked) {
if ((*unlock) () == 0) {
fprintf (stderr, _("%s: failed to unlock %s\n"), progname, fileeditname);
SYSLOG ((LOG_ERR, "failed to unlock %s", fileeditname));
/* continue */
}
}
if (NULL != msg) {
fprintf (stderr, "%s: %s", progname, msg);
}
if (0 != syserr) {
fprintf (stderr, ": %s", strerror (err));
}
(void) fputs ("\n", stderr);
if (!quiet) {
fprintf (stdout, _("%s: %s is unchanged\n"), progname,
filename);
}
exit (ret);
}
#ifndef DEFAULT_EDITOR
#define DEFAULT_EDITOR "vi"
#endif
/*
*
*/
static void
vipwedit (const char *file, int (*file_lock) (void), int (*file_unlock) (void))
{
const char *editor;
pid_t pid;
struct stat st1, st2;
int status;
FILE *f;
/* FIXME: the following should have variable sizes */
char filebackup[1024], fileedit[1024];
char *to_rename;
snprintf (filebackup, sizeof filebackup, "%s-", file);
#ifdef WITH_TCB
if (tcb_mode) {
if ( (mkdir (TCB_DIR "/" SHADOWTCB_SCRATCHDIR, 0700) != 0)
&& (errno != EEXIST)) {
vipwexit (_("failed to create scratch directory"), errno, 1);
}
if (shadowtcb_drop_priv () == SHADOWTCB_FAILURE) {
vipwexit (_("failed to drop privileges"), errno, 1);
}
snprintf (fileedit, sizeof fileedit,
TCB_DIR "/" SHADOWTCB_SCRATCHDIR "/.vipw.shadow.%s",
user);
} else {
#endif /* WITH_TCB */
snprintf (fileedit, sizeof fileedit, "%s.edit", file);
#ifdef WITH_TCB
}
#endif /* WITH_TCB */
unlock = file_unlock;
filename = file;
fileeditname = fileedit;
if (access (file, F_OK) != 0) {
vipwexit (file, 1, 1);
}
#ifdef WITH_SELINUX
/* if SE Linux is enabled then set the context of all new files
to be the context of the file we are editing */
if (is_selinux_enabled ()) {
security_context_t passwd_context=NULL;
int ret = 0;
if (getfilecon (file, &passwd_context) < 0) {
vipwexit (_("Couldn't get file context"), errno, 1);
}
ret = setfscreatecon (passwd_context);
freecon (passwd_context);
if (0 != ret) {
vipwexit (_("setfscreatecon () failed"), errno, 1);
}
}
#endif /* WITH_SELINUX */
#ifdef WITH_TCB
if (tcb_mode && (shadowtcb_gain_priv () == SHADOWTCB_FAILURE)) {
vipwexit (_("failed to gain privileges"), errno, 1);
}
#endif /* WITH_TCB */
if (file_lock () == 0) {
vipwexit (_("Couldn't lock file"), errno, 5);
}
filelocked = true;
#ifdef WITH_TCB
if (tcb_mode && (shadowtcb_drop_priv () == SHADOWTCB_FAILURE)) {
vipwexit (_("failed to drop privileges"), errno, 1);
}
#endif /* WITH_TCB */
/* edited copy has same owners, perm */
if (stat (file, &st1) != 0) {
vipwexit (file, 1, 1);
}
f = fopen (file, "r");
if (NULL == f) {
vipwexit (file, 1, 1);
}
#ifdef WITH_TCB
if (tcb_mode && (shadowtcb_gain_priv () == SHADOWTCB_FAILURE))
vipwexit (_("failed to gain privileges"), errno, 1);
#endif /* WITH_TCB */
if (create_backup_file (f, fileedit, &st1) != 0) {
vipwexit (_("Couldn't make backup"), errno, 1);
}
(void) fclose (f);
createedit = true;
editor = getenv ("VISUAL");
if (NULL == editor) {
editor = getenv ("EDITOR");
}
if (NULL == editor) {
editor = DEFAULT_EDITOR;
}
pid = fork ();
if (-1 == pid) {
vipwexit ("fork", 1, 1);
} else if (0 == pid) {
/* use the system() call to invoke the editor so that it accepts
command line args in the EDITOR and VISUAL environment vars */
char *buf;
buf = (char *) malloc (strlen (editor) + strlen (fileedit) + 2);
snprintf (buf, strlen (editor) + strlen (fileedit) + 2,
"%s %s", editor, fileedit);
if (system (buf) != 0) {
fprintf (stderr, "%s: %s: %s\n", progname, editor,
strerror (errno));
exit (1);
} else {
exit (0);
}
}
for (;;) {
pid = waitpid (pid, &status, WUNTRACED);
if ((pid != -1) && (WIFSTOPPED (status) != 0)) {
/* The child (editor) was suspended.
* Suspend vipw. */
kill (getpid (), SIGSTOP);
/* wake child when resumed */
kill (pid, SIGCONT);
} else {
break;
}
}
if ( (-1 == pid)
|| (WIFEXITED (status) == 0)
|| (WEXITSTATUS (status) != 0)) {
vipwexit (editor, 1, 1);
}
if (stat (fileedit, &st2) != 0) {
vipwexit (fileedit, 1, 1);
}
if (st1.st_mtime == st2.st_mtime) {
vipwexit (0, 0, 0);
}
#ifdef WITH_SELINUX
/* unset the fscreatecon */
if (is_selinux_enabled ()) {
if (setfscreatecon (NULL)) {
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vipwexit (_("setfscreatecon () failed"), errno, 1);
}
}
#endif /* WITH_SELINUX */
/*
* XXX - here we should check fileedit for errors; if there are any,
* ask the user what to do (edit again, save changes anyway, or quit
* without saving). Use pwck or grpck to do the check. --marekm
*/
createedit = false;
#ifdef WITH_TCB
if (tcb_mode) {
f = fopen (fileedit, "r");
if (NULL == f) {
vipwexit (_("failed to open scratch file"), errno, 1);
}
if (unlink (fileedit) != 0) {
vipwexit (_("failed to unlink scratch file"), errno, 1);
}
if (shadowtcb_drop_priv () == SHADOWTCB_FAILURE) {
vipwexit (_("failed to drop privileges"), errno, 1);
}
if (stat (file, &st1) != 0) {
vipwexit (_("failed to stat edited file"), errno, 1);
}
to_rename = malloc (strlen (file) + 2);
if (NULL == to_rename) {
vipwexit (_("failed to allocate memory"), errno, 1);
}
snprintf (to_rename, strlen (file) + 2, "%s+", file);
if (create_backup_file (f, to_rename, &st1) != 0) {
free (to_rename);
vipwexit (_("failed to create backup file"), errno, 1);
}
(void) fclose (f);
} else {
#endif /* WITH_TCB */
to_rename = fileedit;
#ifdef WITH_TCB
}
#endif /* WITH_TCB */
unlink (filebackup);
link (file, filebackup);
if (rename (to_rename, file) == -1) {
fprintf (stderr,
_("%s: can't restore %s: %s (your changes are in %s)\n"),
progname, file, strerror (errno), to_rename);
#ifdef WITH_TCB
if (tcb_mode) {
free (to_rename);
}
#endif /* WITH_TCB */
vipwexit (0, 0, 1);
}
#ifdef WITH_TCB
if (tcb_mode) {
free (to_rename);
if (shadowtcb_gain_priv () == SHADOWTCB_FAILURE) {
vipwexit (_("failed to gain privileges"), errno, 1);
}
}
#endif /* WITH_TCB */
if ((*file_unlock) () == 0) {
fprintf (stderr, _("%s: failed to unlock %s\n"), progname, fileeditname);
SYSLOG ((LOG_ERR, "failed to unlock %s", fileeditname));
/* continue */
}
SYSLOG ((LOG_INFO, "file %s edited", fileeditname));
}
int main (int argc, char **argv)
{
bool editshadow = false;
char *a;
bool do_vipw;
(void) setlocale (LC_ALL, "");
(void) bindtextdomain (PACKAGE, LOCALEDIR);
(void) textdomain (PACKAGE);
progname = ((a = strrchr (*argv, '/')) ? a + 1 : *argv);
do_vipw = (strcmp (progname, "vigr") != 0);
OPENLOG (do_vipw ? "vipw" : "vigr");
{
/*
* Parse the command line options.
*/
int c;
static struct option long_options[] = {
{"group", no_argument, NULL, 'g'},
{"help", no_argument, NULL, 'h'},
{"passwd", no_argument, NULL, 'p'},
{"quiet", no_argument, NULL, 'q'},
{"shadow", no_argument, NULL, 's'},
#ifdef WITH_TCB
{"user", required_argument, NULL, 'u'},
#endif /* WITH_TCB */
{NULL, 0, NULL, '\0'}
};
while ((c = getopt_long (argc, argv,
#ifdef WITH_TCB
"ghpqsu:",
#else /* !WITH_TCB */
"ghpqs",
#endif /* !WITH_TCB */
long_options, NULL)) != -1) {
switch (c) {
case 'g':
do_vipw = false;
break;
case 'h':
usage (E_SUCCESS);
break;
case 'p':
do_vipw = true;
break;
case 'q':
quiet = true;
break;
case 's':
editshadow = true;
break;
#ifdef WITH_TCB
case 'u':
user = optarg;
break;
#endif /* WITH_TCB */
default:
usage (E_USAGE);
}
}
}
if (do_vipw) {
if (editshadow) {
#ifdef WITH_TCB
if (getdef_bool ("USE_TCB") && (NULL != user)) {
if (shadowtcb_set_user (user) == SHADOWTCB_FAILURE) {
fprintf (stderr,
_("%s: failed to find tcb directory for %s\n"),
progname, user);
return E_SHADOW_NOTFOUND;
}
tcb_mode = true;
}
#endif /* WITH_TCB */
vipwedit (spw_dbname (), spw_lock, spw_unlock);
printf (MSG_WARN_EDIT_OTHER_FILE,
spw_dbname (),
pw_dbname (),
"vipw");
} else {
vipwedit (pw_dbname (), pw_lock, pw_unlock);
if (spw_file_present ()) {
printf (MSG_WARN_EDIT_OTHER_FILE,
pw_dbname (),
spw_dbname (),
"vipw -s");
}
}
} else {
#ifdef SHADOWGRP
if (editshadow) {
vipwedit (sgr_dbname (), sgr_lock, sgr_unlock);
printf (MSG_WARN_EDIT_OTHER_FILE,
sgr_dbname (),
gr_dbname (),
"vigr");
} else {
#endif /* SHADOWGRP */
vipwedit (gr_dbname (), gr_lock, gr_unlock);
#ifdef SHADOWGRP
if (sgr_file_present ()) {
printf (MSG_WARN_EDIT_OTHER_FILE,
gr_dbname (),
sgr_dbname (),
"vigr -s");
}
}
#endif /* SHADOWGRP */
}
nscd_flush_cache ("passwd");
nscd_flush_cache ("group");
return E_SUCCESS;
}