/*      $OpenBSD: field.c,v 1.15 2023/03/08 04:43:10 guenther Exp $     */
/*      $NetBSD: field.c,v 1.3 1995/03/26 04:55:28 glass Exp $  */

/*
 * Copyright (c) 1988, 1993, 1994
 *      The 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. 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.
 */

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <grp.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <limits.h>

#include "chpass.h"

int
p_login(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!*p) {
                warnx("empty login field");
                return (1);
        }
        if (*p == '-') {
                warnx("login names may not begin with a hyphen");
                return (1);
        }
        /* XXX - what about truncated names? */
        if (strcmp(pw->pw_name, p) != 0 && getpwnam(p) != NULL) {
                warnx("login %s already exists", p);
                return (1);
        }
        if (!(pw->pw_name = strdup(p))) {
                warnx("can't save entry");
                return (1);
        }
        if (strchr(p, '.'))
                warnx("\'.\' is dangerous in a login name");
        for (; *p; ++p)
                if (isupper((unsigned char)*p)) {
                        warnx("upper-case letters are dangerous in a login name");
                        break;
                }
        return (0);
}

int
p_passwd(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!*p)
                pw->pw_passwd = "";     /* "NOLOGIN"; */
        else if (!(pw->pw_passwd = strdup(p))) {
                warnx("can't save password entry");
                return (1);
        }

        return (0);
}

int
p_uid(char *p, struct passwd *pw, ENTRY *ep)
{
        uid_t id;
        const char *errstr;

        if (!*p) {
                warnx("empty uid field");
                return (1);
        }
        id = (uid_t)strtonum(p, 0, UID_MAX, &errstr);
        if (errstr) {
                warnx("uid is %s", errstr);
                return (1);
        }
        pw->pw_uid = id;
        return (0);
}

int
p_gid(char *p, struct passwd *pw, ENTRY *ep)
{
        struct group *gr;
        const char *errstr;
        gid_t id;

        if (!*p) {
                warnx("empty gid field");
                return (1);
        }
        if (!isdigit((unsigned char)*p)) {
                if (!(gr = getgrnam(p))) {
                        warnx("unknown group %s", p);
                        return (1);
                }
                pw->pw_gid = gr->gr_gid;
                return (0);
        }
        id = (uid_t)strtonum(p, 0, GID_MAX, &errstr);
        if (errstr) {
                warnx("gid is %s", errstr);
                return (1);
        }
        pw->pw_gid = id;
        return (0);
}

int
p_class(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!*p)
                pw->pw_class = "";
        else if (!(pw->pw_class = strdup(p))) {
                warnx("can't save entry");
                return (1);
        }

        return (0);
}

int
p_change(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!atot(p, &pw->pw_change))
                return (0);
        warnx("illegal date for change field");
        return (1);
}

int
p_expire(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!atot(p, &pw->pw_expire))
                return (0);
        warnx("illegal date for expire field");
        return (1);
}

int
p_gecos(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!*p)
                ep->save = "";
        else if (!(ep->save = strdup(p))) {
                warnx("can't save entry");
                return (1);
        }
        return (0);
}

int
p_hdir(char *p, struct passwd *pw, ENTRY *ep)
{
        if (!*p) {
                warnx("empty home directory field");
                return (1);
        }
        if (!(pw->pw_dir = strdup(p))) {
                warnx("can't save entry");
                return (1);
        }
        return (0);
}

int
p_shell(char *p, struct passwd *pw, ENTRY *ep)
{
        char *t;

        if (!*p) {
                pw->pw_shell = _PATH_BSHELL;
                return (0);
        }
        /* only admin can change from or to "restricted" shells */
        if (uid && pw->pw_shell && !ok_shell(pw->pw_shell, NULL)) {
                warnx("%s: current shell non-standard", pw->pw_shell);
                return (1);
        }
        if (!ok_shell(p, &t)) {
                if (uid) {
                        warnx("%s: non-standard shell", p);
                        return (1);
                } else
                        t = strdup(p);
        }
        if (!(pw->pw_shell = t)) {
                warnx("can't save entry");
                return (1);
        }
        return (0);
}