/*

  Linux DNS client library implementation

  Copyright (C) 2006 Krishna Ganugapati <krishnag@centeris.com>

  Copyright (C) 2006 Gerald Carter <jerry@samba.org>

     ** NOTE! The following LGPL license applies to the libaddns

     ** library. This does NOT imply that all of Samba is released

     ** under the LGPL

  This library is free software; you can redistribute it and/or

  modify it under the terms of the GNU Lesser General Public

  License as published by the Free Software Foundation; either

  version 2.1 of the License, or (at your option) any later version.

  This library 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

  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public

  License along with this library; if not, see <http://www.gnu.org/licenses/>.

*/

#include "includes.h"

#include "librpc/ndr/libndr.h"

#include "librpc/gen_ndr/ndr_misc.h"

#include "dns.h"

#include <ctype.h>

static DNS_ERROR LabelList( TALLOC_CTX *mem_ctx,

          const char *name,

          struct dns_domain_label **presult )

{

  struct dns_domain_label *result;

  const char *dot;

  for (dot = name; *dot != '\0'; dot += 1) {

    char c = *dot;

    if (c == '.')

      break;

    if (c == '-') continue;

    if ((c >= 'a') && (c <= 'z')) continue;

    if ((c >= 'A') && (c <= 'Z')) continue;

    if ((c >= '0') && (c <= '9')) continue;

    return ERROR_DNS_INVALID_NAME;

  }

  if ((dot - name) > 63) {

    /*

     * DNS labels can only be 63 chars long

     */

    return ERROR_DNS_INVALID_NAME;

  }

  if (!(result = talloc_zero(mem_ctx, struct dns_domain_label))) {

    return ERROR_DNS_NO_MEMORY;

  }

  if (*dot == '\0') {

    /*

     * No dot around, so this is the last component

     */

    if (!(result->label = talloc_strdup(result, name))) {

      TALLOC_FREE(result);

      return ERROR_DNS_NO_MEMORY;

    }

    result->len = strlen(result->label);

    *presult = result;

    return ERROR_DNS_SUCCESS;

  }

  if (dot[1] == '.') {

    /*

     * Two dots in a row, reject

     */

    TALLOC_FREE(result);

    return ERROR_DNS_INVALID_NAME;

  }

  if (dot[1] != '\0') {

    /*

     * Something follows, get the rest

     */

    DNS_ERROR err = LabelList(result, dot+1, &result->next);

    if (!ERR_DNS_IS_OK(err)) {

      TALLOC_FREE(result);

      return err;

    }

  }

  result->len = (dot - name);

  if (!(result->label = talloc_strndup(result, name, result->len))) {

    TALLOC_FREE(result);

    return ERROR_DNS_NO_MEMORY;

  }

  *presult = result;

  return ERROR_DNS_SUCCESS;

}

DNS_ERROR dns_domain_name_from_string( TALLOC_CTX *mem_ctx,

               const char *pszDomainName,

               struct dns_domain_name **presult )

{

  struct dns_domain_name *result;

  DNS_ERROR err;

  if (!(result = talloc(mem_ctx, struct dns_domain_name))) {

    return ERROR_DNS_NO_MEMORY;

  }

  err = LabelList( result, pszDomainName, &result->pLabelList );

  if (!ERR_DNS_IS_OK(err)) {

    TALLOC_FREE(result);

    return err;

  }

  *presult = result;

  return ERROR_DNS_SUCCESS;

}

/*********************************************************************

*********************************************************************/

char *dns_generate_keyname( TALLOC_CTX *mem_ctx )

{

  char *result = NULL;

#if defined(HAVE_KRB5)

  struct GUID guid;

  guid = GUID_random();

  result = GUID_string(mem_ctx, &guid);

#endif

  return result;

}