/*
 * FreeIPA 2FA companion daemon
 *
 * Authors: Nathaniel McCallum <npmccallum@redhat.com>
 *
 * Copyright (C) 2013  Nathaniel McCallum, Red Hat
 * see file 'COPYING' for use and warranty information
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */

/*
 * This file parses the user's configuration received from LDAP (see query.c).
 */

#include "internal.h"
#include <ctype.h>

#define DEFAULT_TIMEOUT 15
#define DEFAULT_RETRIES 3

/* Convert an LDAP entry into an allocated string. */
static int get_string(LDAP *ldp, LDAPMessage *entry, const char *name,
                      char **out)
{
    struct berval **vals;
    ber_len_t i;
    char *buf;

    vals = ldap_get_values_len(ldp, entry, name);
    if (vals == NULL)
        return ENOENT;

    buf = calloc(vals[0]->bv_len + 1, sizeof(char));
    if (buf == NULL) {
        ldap_value_free_len(vals);
        return ENOMEM;
    }

    for (i = 0; i < vals[0]->bv_len; i++) {
        if (!isprint(vals[0]->bv_val[i])) {
            free(buf);
            ldap_value_free_len(vals);
            return EINVAL;
        }

        buf[i] = vals[0]->bv_val[i];
    }

    if (*out != NULL)
        free(*out);
    *out = buf;
    ldap_value_free_len(vals);
    return 0;
}

/* Convert an LDAP entry into an unsigned long. */
static int get_ulong(LDAP *ldp, LDAPMessage *entry, const char *name,
                     unsigned long *out)
{
    struct berval **vals;
    char buffer[32];

    vals = ldap_get_values_len(ldp, entry, name);
    if (vals == NULL)
        return ENOENT;

    if (vals[0]->bv_len > sizeof(buffer) - 1) {
        ldap_value_free_len(vals);
        return ERANGE;
    }

    memcpy(buffer, vals[0]->bv_val, vals[0]->bv_len);
    buffer[vals[0]->bv_len] = '\0';
    ldap_value_free_len(vals);

    *out = strtoul(buffer, NULL, 10);
    if (*out == ULONG_MAX)
        return errno;

    return 0;
}

/* Parse basic user configuration. */
const char *otpd_parse_user(LDAP *ldp, LDAPMessage *entry,
                            struct otpd_queue_item *item)
{
  int i, j;

  i = get_string(ldp, entry, "uid", &item->user.uid);
  if (i != 0)
      return strerror(i);

  i = get_string(ldp, entry, "ipatokenRadiusUserName",
                 &item->user.ipatokenRadiusUserName);
  if (i != 0 && i != ENOENT)
      return strerror(i);

  i = get_string(ldp, entry, "ipatokenRadiusConfigLink",
                 &item->user.ipatokenRadiusConfigLink);
  if (i != 0 && i != ENOENT)
      return strerror(i);

  /* Get the DN. */
  item->user.dn = ldap_get_dn(ldp, entry);
  if (item->user.dn == NULL) {
      i = ldap_get_option(ldp, LDAP_OPT_RESULT_CODE, &j);
      return ldap_err2string(i == LDAP_OPT_SUCCESS ? j : i);
  }

  return NULL;
}

/* Parse the user's RADIUS configuration. */
const char *otpd_parse_radius(LDAP *ldp, LDAPMessage *entry,
                              struct otpd_queue_item *item)
{
  unsigned long l;
  int i;

  i = get_string(ldp, entry, "ipatokenRadiusServer",
                 &item->radius.ipatokenRadiusServer);
  if (i != 0)
      return strerror(i);

  i = get_string(ldp, entry, "ipatokenRadiusSecret",
                 &item->radius.ipatokenRadiusSecret);
  if (i != 0)
      return strerror(i);

  i = get_string(ldp, entry, "ipatokenUserMapAttribute",
                 &item->radius.ipatokenUserMapAttribute);
  if (i != 0 && i != ENOENT)
      return strerror(i);

  i = get_ulong(ldp, entry, "ipatokenRadiusTimeout", &l);
  if (i == ENOENT)
      l = DEFAULT_TIMEOUT;
  else if (i != 0)
      return strerror(i);
  item->radius.ipatokenRadiusTimeout = l * 1000;

  i = get_ulong(ldp, entry, "ipatokenRadiusRetries", &l);
  if (i == ENOENT)
      l = DEFAULT_RETRIES;
  else if (i != 0)
      return strerror(i);
  item->radius.ipatokenRadiusRetries = l;

  return NULL;
}

/* Parse the user's RADIUS username. */
const char *otpd_parse_radius_username(LDAP *ldp, LDAPMessage *entry,
                                       struct otpd_queue_item *item)
{
  int i;

  i = get_string(ldp, entry, item->radius.ipatokenUserMapAttribute,
                 &item->user.other);
  if (i != 0)
      return strerror(i);

  return NULL;
}