/* vi: set sw=4 ts=4: */
/*
 * addgroup - add users to /etc/passwd and /etc/shadow
 *
 *
 * Copyright (C) 1999 by Lineo, inc.
 * Written by John Beppu <beppu@lineo.com>
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include "tinylogin.h"
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <getopt.h>


/* structs __________________________ */

/* data _____________________________ */

/* defaults : should this be in an external file? */
static char *default_passwd = "x";


/* make sure gr_name isn't taken, make sure gid is kosher
 * return 1 on failure */
static int group_study(const char *filename, struct group *g, char* paucMessage)
{
	FILE *etc_group;
	gid_t desired;

	struct group *grp;
	const int max = 65000;

	/* FIXME : make an fopen_wrapper */
	etc_group = fopen(filename, "r");
	if (!etc_group) {
		strcpy(paucMessage, filename);
	}

	/* make sure gr_name isn't taken, make sure gid is kosher */
	desired = g->gr_gid;
	while ((grp = tlg_fgetgrent(etc_group))) {
		if ((strcmp(grp->gr_name, g->gr_name)) == 0) {
			sprintf(paucMessage, "%s: group already in use", g->gr_name);
		}
		if ((desired) && grp->gr_gid == desired) {
			sprintf(paucMessage, "%d: gid has already been allocated", desired);
		}
		if ((grp->gr_gid > g->gr_gid) && (grp->gr_gid < max)) {
			g->gr_gid = grp->gr_gid;
		}
	}
	fclose(etc_group);

	/* gid */
	if (desired) {
		g->gr_gid = desired;
	} else {
		g->gr_gid++;
	}
	/* return 1; */
	return 0;
}

/* append a new user to the passwd file */
static int addgroup(const char *filename, char *group, gid_t gid, char* paucMessage)
{
	FILE *etc_group;

#ifdef TLG_FEATURE_SHADOWPASSWDS
	FILE *etc_gshadow;
	char *gshadow = GSHADOW_FILE;
#endif							/* TLG_FEATURE_SHADOWPASSWDS */

	struct group gr;

	/* group:passwd:gid:userlist */
	const char *entryfmt = "%s:%s:%d:%s\n";

	/* make sure gid and group haven't already been allocated */
	gr.gr_gid = gid;
	gr.gr_name = group;
	if (group_study(filename, &gr, paucMessage))
		return 1;

	/* add entry to group */
	etc_group = fopen(filename, "a");
	if (!etc_group) {
		strcpy(paucMessage, filename);
                return 1;
	}
	fprintf(etc_group, entryfmt, group, default_passwd, gr.gr_gid, "");
	fclose(etc_group);

#ifdef TLG_FEATURE_SHADOWPASSWDS
	/* add entry to gshadow if necessary */
	if (access(gshadow, W_OK) == 0) {
		etc_gshadow = fopen(gshadow, "a");
		if (!etc_gshadow) {
			strcpy(paucMessage, gshadow);
                        return 1;
		}
		fprintf(etc_gshadow, "%s:!::\n", group);
		fclose(etc_gshadow);
	}
#endif							/* TLG_FEATURE_SHADOWPASSWDS */

	/* return 1; */
	return 0;
}

/*
 * addgroup will take a login_name as its first parameter.
 *
 * gid 
 *
 * can be customized via command-line parameters.
 * ________________________________________________________________________ */
int setgroup_main(int argc, char **argv , char* paucMessage)
{
	char opt;
	char *group;
	gid_t gid = 0;

	if (argc < 2) {
//		usage(addgroup_usage);
		return 1;
	}

	while ((opt = getopt(argc, argv, "g:")) != EOF) {
		switch (opt) {
		case 'g':
			gid = strtol(optarg, NULL, 10);
			break;
		default:
//			usage(addgroup_usage);
			exit(1);
		}
	}

	if (optind >= argc) {
//		usage(addgroup_usage);
        return 1; //Coverity Bug# 734
	} else {
		group = argv[optind];
	}

	if (geteuid() != 0) {
            strcpy(paucMessage, "addgroup: Only root may add a group to the system.\n");
            return 1;
	}

	/* werk */
	return addgroup(GROUP_FILE, group, gid, paucMessage);
}

/* $Id: addgroup.c,v 1.1 2006/11/14 04:48:28 skatraga Exp $ */
