
/*
 * FCRON - periodic command scheduler 
 *
 *  Copyright 2000-2024 Thibault Godouet <fcron@free.fr>
 *
 *  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
 * 
 *  The GNU General Public License can also be found in the file
 *  `LICENSE' that comes with the fcron source distribution.
 */


#include "fcrontab.h"

#include "allow.h"

int
in_file(char *str, char *file)
    /* return -1 if file doesn't exist
     *        0 if string is not in file,
     *        1 if it is in file
     *   and  2 if file contains "all" string */
{
    char buf[LINE_LEN];
    FILE *f = NULL;
    char *start = NULL;

    if ((f = fopen(file, "r")) == NULL) {
        if (errno == ENOENT)
            /* file does not exist */
            return -1;
        else
            die_e("could not open %s", file);
    }

    while (fgets(buf, sizeof(buf), f) != NULL) {

        /* skip leading and trailing blanks, comments */
        start = buf;
        Skip_blanks(start);
        if (*start == '#' || *start == '\0')
            continue;
        remove_blanks(start);

        if (strcmp(str, start) == 0) {
            xfclose_check(&f, file);
            return 1;
        }
        if (strcmp(start, "all") == 0) {
            xfclose_check(&f, file);
            return 2;
        }
    }

    xfclose_check(&f, file);
    /* if execution gets here, string is not in file */
    return 0;


}

int
is_allowed(char *user)
    /* return 1 if user is allowed to use this software
     * otherwise return 0 */
{
    int allow = 0;
    int deny = 0;

    /* check if user is in passwd file */
    if (getpwnam(user) != NULL) {

        /* check if user is in fcron.allow and/or in fcron.deny files */
        allow = in_file(user, fcronallow);
        deny = in_file(user, fcrondeny);

        /* in_file() returns:
         *       -1 if file doesn't exist
         *        0 if string is not in file,
         *        1 if it is in file
         *   and  2 if file contains "all" string */

        if (allow == -1 && deny == -1)
            /* neither fcron.allow nor fcron.deny exist :
             * we consider that user is allowed */
            return 1;

        if (allow == -1 && deny == 0)
            return 1;

        if (deny == -1 && allow == 1)
            return 1;

        if (allow == 1 && deny != 1)
            return 1;
        if (allow == 2 && deny <= 0)
            return 1;

    }

    /* if we gets here, user is not allowed */

#ifdef WITH_AUDIT
    {
        int audit_fd = audit_open();
        audit_log_user_message(audit_fd, AUDIT_USER_START, "fcron deny",
                               NULL, NULL, NULL, 0);
        xclose_check(&audit_fd, "audit");
    }
#endif

    return 0;

}
