Logo Search packages:      
Sourcecode: shadow version File versions

groupmod.c

/*
 * Copyright 1991 - 1994, Julianne Frances Haugh
 * 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 Julianne F. Haugh 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 JULIE HAUGH 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 JULIE HAUGH 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 <config.h>

#undef USE_PAM

#include "rcsid.h"
RCSID (PKG_VER "$Id: groupmod.c 6 2005-03-20 15:34:28Z bubulle $")
#include <sys/types.h>
#include <stdio.h>
#include <grp.h>
#include <ctype.h>
#include <fcntl.h>
#ifdef USE_PAM
#include <security/pam_appl.h>
#include <security/pam_misc.h>
#include <pwd.h>
#endif                        /* USE_PAM */
#include "prototypes.h"
#include "chkname.h"
#include "defines.h"
#include "groupio.h"
#ifdef      SHADOWGRP
#include "sgroupio.h"
static int is_shadow_grp;
#endif

/*
 * exit status values
 */

#define E_SUCCESS 0     /* success */
#define E_USAGE         2     /* invalid command syntax */
#define E_BAD_ARG 3     /* invalid argument to option */
#define E_GID_IN_USE    4     /* gid already in use (and no -o) */
#define E_NOTFOUND      6     /* specified group doesn't exist */
#define E_NAME_IN_USE   9     /* group name already in use */
#define E_GRP_UPDATE    10    /* can't update group file */

static char *group_name;
static char *group_newname;
static gid_t group_id;
static gid_t group_newid;

static char *Prog;

static int
 oflg = 0,              /* permit non-unique group ID to be specified with -g */
 gflg = 0,              /* new ID value for the group */
 nflg = 0;              /* a new name has been specified for the group */

#ifdef      NDBM
extern int gr_dbm_mode;
extern int sg_dbm_mode;
#endif

/* local function prototypes */
static void usage (void);
static void new_grent (struct group *);

#ifdef SHADOWGRP
static void new_sgent (struct sgrp *);
#endif
static void grp_update (void);
static void check_new_gid (void);
static void check_new_name (void);
static void process_flags (int, char **);
static void close_files (void);
static void open_files (void);

/*
 * usage - display usage message and exit
 */

static void usage (void)
{
      fprintf (stderr,
             _("usage: groupmod [-g gid [-o]] [-n name] group\n"));
      exit (E_USAGE);
}

/*
 * new_grent - updates the values in a group file entry
 *
 *    new_grent() takes all of the values that have been entered and fills
 *    in a (struct group) with them.
 */

static void new_grent (struct group *grent)
{
      if (nflg)
            grent->gr_name = xstrdup (group_newname);

      if (gflg)
            grent->gr_gid = group_newid;
}

#ifdef      SHADOWGRP
/*
 * new_sgent - updates the values in a shadow group file entry
 *
 *    new_sgent() takes all of the values that have been entered and fills
 *    in a (struct sgrp) with them.
 */

static void new_sgent (struct sgrp *sgent)
{
      if (nflg)
            sgent->sg_name = xstrdup (group_newname);
}
#endif                        /* SHADOWGRP */

/*
 * grp_update - update group file entries
 *
 *    grp_update() writes the new records to the group files.
 */

static void grp_update (void)
{
      struct group grp;
      const struct group *ogrp;

#ifdef      SHADOWGRP
      struct sgrp sgrp;
      const struct sgrp *osgrp = NULL;
#endif                        /* SHADOWGRP */

      /*
       * Get the current settings for this group.
       */

      ogrp = gr_locate (group_name);
      if (!ogrp) {
            fprintf (stderr,
                   _("%s: %s not found in /etc/group\n"),
                   Prog, group_name);
            exit (E_GRP_UPDATE);
      }
      grp = *ogrp;
      new_grent (&grp);
#ifdef      SHADOWGRP
      if (is_shadow_grp && (osgrp = sgr_locate (group_name))) {
            sgrp = *osgrp;
            new_sgent (&sgrp);
      }
#endif                        /* SHADOWGRP */

      /*
       * Write out the new group file entry.
       */

      if (!gr_update (&grp)) {
            fprintf (stderr, _("%s: error adding new group entry\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      if (nflg && !gr_remove (group_name)) {
            fprintf (stderr, _("%s: error removing group entry\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
#ifdef      NDBM

      /*
       * Update the DBM group file with the new entry as well.
       */

      if (gr_dbm_present ()) {
            if (!gr_dbm_update (&grp)) {
                  fprintf (stderr,
                         _("%s: cannot add new dbm group entry\n"),
                         Prog);
                  exit (E_GRP_UPDATE);
            }
            if (nflg && (ogrp = getgrnam (group_name)) &&
                !gr_dbm_remove (ogrp)) {
                  fprintf (stderr,
                         _("%s: error removing group dbm entry\n"),
                         Prog);
                  exit (E_GRP_UPDATE);
            }
            endgrent ();
      }
#endif                        /* NDBM */

#ifdef      SHADOWGRP

      /*
       * Make sure there was a shadow entry to begin with. Skip down to
       * "out" if there wasn't. Can't just return because there might be
       * some syslogging to do.
       */

      if (!osgrp)
            goto out;

      /*
       * Write out the new shadow group entries as well.
       */

      if (!sgr_update (&sgrp)) {
            fprintf (stderr, _("%s: error adding new group entry\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      if (nflg && !sgr_remove (group_name)) {
            fprintf (stderr, _("%s: error removing group entry\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
#ifdef      NDBM

      /*
       * Update the DBM shadow group file with the new entry as well.
       */

      if (sg_dbm_present ()) {
            if (!sg_dbm_update (&sgrp)) {
                  fprintf (stderr,
                         _
                         ("%s: cannot add new dbm shadow group entry\n"),
                         Prog);
                  exit (E_GRP_UPDATE);
            }
            if (nflg && !sg_dbm_remove (group_name)) {
                  fprintf (stderr,
                         _
                         ("%s: error removing shadow group dbm entry\n"),
                         Prog);
                  exit (E_GRP_UPDATE);
            }
            endsgent ();
      }
#endif                        /* NDBM */
      out:
#endif                        /* SHADOWGRP */

      if (nflg)
            SYSLOG ((LOG_INFO, "change group `%s' to `%s'",
                   group_name, group_newname));

      if (gflg)
            SYSLOG ((LOG_INFO, "change gid for `%s' to %u",
                   nflg ? group_newname : group_name, group_newid));
}

/*
 * check_new_gid - check the new GID value for uniqueness
 *
 *    check_new_gid() insures that the new GID value is unique.
 */

static void check_new_gid (void)
{
      /*
       * First, the easy stuff. If the ID can be duplicated, or if the ID
       * didn't really change, just return. If the ID didn't change, turn
       * off those flags. No sense doing needless work.
       */

      if (group_id == group_newid) {
            gflg = 0;
            return;
      }

      if (oflg || !getgrgid (group_newid))
            return;

      /*
       * Tell the user what they did wrong.
       */

      fprintf (stderr,
             _("%s: %u is not a unique gid\n"), Prog, group_newid);
      exit (E_GID_IN_USE);
}

/*
 * check_new_name - check the new name for uniqueness
 *
 *    check_new_name() insures that the new name does not exist already.
 *    You can't have the same name twice, period.
 */

static void check_new_name (void)
{
      /*
       * Make sure they are actually changing the name.
       */

      if (strcmp (group_name, group_newname) == 0) {
            nflg = 0;
            return;
      }

      if (check_group_name (group_newname)) {

            /*
             * If the entry is found, too bad.
             */

            if (getgrnam (group_newname)) {
                  fprintf (stderr,
                         _("%s: %s is not a unique name\n"), Prog,
                         group_newname);
                  exit (E_NAME_IN_USE);
            }
            return;
      }

      /*
       * All invalid group names land here.
       */

      fprintf (stderr, _("%s: %s is a not a valid group name\n"),
             Prog, group_newname);
      exit (E_BAD_ARG);
}

/*
 * process_flags - perform command line argument setting
 *
 *    process_flags() interprets the command line arguments and sets the
 *    values that the user will be created with accordingly. The values
 *    are checked for sanity.
 */

static void process_flags (int argc, char **argv)
{
      char *end;
      int arg;

      while ((arg = getopt (argc, argv, "og:n:")) != EOF) {
            switch (arg) {
            case 'g':
                  gflg++;
                  group_newid = strtoul (optarg, &end, 10);
                  if (*end != '\0') {
                        fprintf (stderr,
                               _("%s: invalid group %s\n"),
                               Prog, optarg);
                        exit (E_BAD_ARG);
                  }
                  break;
            case 'n':
                  nflg++;
                  group_newname = optarg;
                  break;
            case 'o':
                  oflg++;
                  break;
            default:
                  usage ();
            }
      }
      if (oflg && !gflg)
            usage ();

      if (optind != argc - 1)
            usage ();

      group_name = argv[argc - 1];
}

/*
 * close_files - close all of the files that were opened
 *
 *    close_files() closes all of the files that were opened for this new
 *    group. This causes any modified entries to be written out.
 */

static void close_files (void)
{
      if (!gr_close ()) {
            fprintf (stderr, _("%s: cannot rewrite group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      gr_unlock ();
#ifdef      SHADOWGRP
      if (is_shadow_grp && !sgr_close ()) {
            fprintf (stderr,
                   _("%s: cannot rewrite shadow group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      if (is_shadow_grp)
            sgr_unlock ();
#endif                        /* SHADOWGRP */
}

/*
 * open_files - lock and open the group files
 *
 *    open_files() opens the two group files.
 */

static void open_files (void)
{
      if (!gr_lock ()) {
            fprintf (stderr, _("%s: unable to lock group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      if (!gr_open (O_RDWR)) {
            fprintf (stderr, _("%s: unable to open group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
#ifdef      SHADOWGRP
      if (is_shadow_grp && !sgr_lock ()) {
            fprintf (stderr,
                   _("%s: unable to lock shadow group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
      if (is_shadow_grp && !sgr_open (O_RDWR)) {
            fprintf (stderr,
                   _("%s: unable to open shadow group file\n"),
                   Prog);
            exit (E_GRP_UPDATE);
      }
#endif                        /* SHADOWGRP */
}

#ifdef USE_PAM
static struct pam_conv conv = {
      misc_conv,
      NULL
};
#endif                        /* USE_PAM */

/*
 * main - groupmod command
 *
 *    The syntax of the groupmod command is
 *    
 *    groupmod [ -g gid [ -o ]] [ -n name ] group
 *
 *    The flags are
 *          -g - specify a new group ID value
 *          -o - permit the group ID value to be non-unique
 *          -n - specify a new group name
 */

int main (int argc, char **argv)
{
      struct group *grp;

#ifdef USE_PAM
      pam_handle_t *pamh = NULL;
      struct passwd *pampw;
      int retval;
#endif

      /*
       * Get my name so that I can use it to report errors.
       */

      Prog = Basename (argv[0]);

      setlocale (LC_ALL, "");
      bindtextdomain (PACKAGE, LOCALEDIR);
      textdomain (PACKAGE);

#ifdef USE_PAM
      retval = PAM_SUCCESS;

      pampw = getpwuid (getuid ());
      if (pampw == NULL) {
            retval = PAM_USER_UNKNOWN;
      }

      if (retval == PAM_SUCCESS) {
            retval =
                pam_start ("shadow", pampw->pw_name, &conv, &pamh);
      }

      if (retval == PAM_SUCCESS) {
            retval = pam_authenticate (pamh, 0);
            if (retval != PAM_SUCCESS) {
                  pam_end (pamh, retval);
            }
      }

      if (retval == PAM_SUCCESS) {
            retval = pam_acct_mgmt (pamh, 0);
            if (retval != PAM_SUCCESS) {
                  pam_end (pamh, retval);
            }
      }

      if (retval != PAM_SUCCESS) {
            fprintf (stderr, _("%s: PAM authentication failed\n"),
                   Prog);
            exit (1);
      }
#endif                        /* USE_PAM */

      OPENLOG (Prog);

#ifdef SHADOWGRP
      is_shadow_grp = sgr_file_present ();
#endif

      /*
       * The open routines for the DBM files don't use read-write as the
       * mode, so we have to clue them in.
       */

#ifdef      NDBM
      gr_dbm_mode = O_RDWR;
#ifdef      SHADOWGRP
      sg_dbm_mode = O_RDWR;
#endif                        /* SHADOWGRP */
#endif                        /* NDBM */
      process_flags (argc, argv);

      /*
       * Start with a quick check to see if the group exists.
       */

      if (!(grp = getgrnam (group_name))) {
            fprintf (stderr, _("%s: group %s does not exist\n"),
                   Prog, group_name);
            exit (E_NOTFOUND);
      } else
            group_id = grp->gr_gid;

#ifdef      USE_NIS

      /*
       * Now make sure it isn't an NIS group.
       */

      if (__isgrNIS ()) {
            char *nis_domain;
            char *nis_master;

            fprintf (stderr, _("%s: group %s is a NIS group\n"),
                   Prog, group_name);

            if (!yp_get_default_domain (&nis_domain) &&
                !yp_master (nis_domain, "group.byname", &nis_master)) {
                  fprintf (stderr, _("%s: %s is the NIS master\n"),
                         Prog, nis_master);
            }
            exit (E_NOTFOUND);
      }
#endif

      if (gflg)
            check_new_gid ();

      if (nflg)
            check_new_name ();

      /*
       * Do the hard stuff - open the files, create the group entries,
       * then close and update the files.
       */

      open_files ();

      grp_update ();

      close_files ();

#ifdef USE_PAM
      if (retval == PAM_SUCCESS) {
            retval = pam_chauthtok (pamh, 0);
            if (retval != PAM_SUCCESS) {
                  pam_end (pamh, retval);
            }
      }

      if (retval != PAM_SUCCESS) {
            fprintf (stderr, _("%s: PAM chauthtok failed\n"), Prog);
            exit (1);
      }

      if (retval == PAM_SUCCESS)
            pam_end (pamh, PAM_SUCCESS);
#endif                        /* USE_PAM */
      exit (E_SUCCESS);
 /*NOTREACHED*/}

Generated by  Doxygen 1.6.0   Back to index