/* Copyright (C) 1996-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1996.

   The GNU C 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.

   The GNU C 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 the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <nss.h>

#include <ctype.h>

#include <errno.h>

#include <string.h>

/* The following is an ugly trick to avoid a prototype declaration for

   _nss_nis_endspent.  */

#define _nss_nis_endspent _nss_nis_endspent_XXX

#include <shadow.h>

#undef _nss_nis_endspent

#include <libc-lock.h>

#include <rpcsvc/yp.h>

#include <rpcsvc/ypclnt.h>

#include "nss-nis.h"

#include <libnsl.h>

/* Get the declaration of the parser function.  */

#define ENTNAME spent

#define STRUCTURE spwd

#define EXTERN_PARSER

#include <nss/nss_files/files-parse.c>

/* Protect global state against multiple changers */

__libc_lock_define_initialized (static, lock)

static bool new_start = true;

static bool ent_adjunct_used;

static char *oldkey;

static int oldkeylen;

enum nss_status

_nss_nis_setspent (int stayopen)

{

  __libc_lock_lock (lock);

  new_start = true;

  ent_adjunct_used = false;

  free (oldkey);

  oldkey = NULL;

  oldkeylen = 0;

  __libc_lock_unlock (lock);

  return NSS_STATUS_SUCCESS;

}

/* Make _nss_nis_endspent an alias of _nss_nis_setspent.  We do this

   even though the prototypes don't match.  The argument of setspent

   is not used so this makes no difference.  */

strong_alias (_nss_nis_setspent, _nss_nis_endspent)

static enum nss_status

internal_nis_getspent_r (struct spwd *sp, char *buffer, size_t buflen,

			 int *errnop)

{

  char *domain;

  if (__glibc_unlikely (yp_get_default_domain (&domain)))

    return NSS_STATUS_UNAVAIL;

  /* Get the next entry until we found a correct one. */

  int parse_res;

  do

    {

      char *result;

      char *outkey;

      int len;

      int keylen;

      int yperr;

      if (new_start)

	{

	  yperr = yp_first (domain, "shadow.byname", &outkey, &keylen, &result,

			    &len;;

	  if (__builtin_expect (yperr == YPERR_MAP, 0)

	      && (_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW))

	    {

	      free (result);

	      yperr = yp_first (domain, "passwd.adjunct.byname", &outkey,

				&keylen, &result, &len;;

	      ent_adjunct_used = true;

	    }

	}

      else

	yperr = yp_next (domain, (ent_adjunct_used

				  ? "passwd.adjunct.byname" : "shadow.byname"),

			 oldkey, oldkeylen, &outkey, &keylen, &result, &len;;

      if (__glibc_unlikely (yperr != YPERR_SUCCESS))

	{

	  enum nss_status retval = yperr2nss (yperr);

	  if (retval == NSS_STATUS_TRYAGAIN)

	    *errnop = errno;

	  return retval;

	}

      if (__builtin_expect ((size_t) (len + (ent_adjunct_used ? 3 : 1))

			    > buflen, 0))

	{

	  free (result);

	  *errnop = ERANGE;

	  return NSS_STATUS_TRYAGAIN;

	}

      char *p = strncpy (buffer, result, len);

      if (ent_adjunct_used)

	/* This is an ugly trick.  The format of passwd.adjunct.byname almost

	   matches the shadow.byname format except that the last two fields

	   are missing.  Synthesize them by marking them empty.  */

	strcpy (&buffer[len], "::");

      else

	buffer[len] = '\0';

      while (isspace (*p))

	++p;

      free (result);

      parse_res = _nss_files_parse_spent (p, sp, (void *) buffer, buflen,

					  errnop);

      if (__builtin_expect  (parse_res == -1, 0))

	{

	  free (outkey);

	  *errnop = ERANGE;

	  return NSS_STATUS_TRYAGAIN;

	}

      free (oldkey);

      oldkey = outkey;

      oldkeylen = keylen;

      new_start = false;

    }

  while (!parse_res);

  return NSS_STATUS_SUCCESS;

}

enum nss_status

_nss_nis_getspent_r (struct spwd *result, char *buffer, size_t buflen,

		     int *errnop)

{

  int status;

  __libc_lock_lock (lock);

  status = internal_nis_getspent_r (result, buffer, buflen, errnop);

  __libc_lock_unlock (lock);

  return status;

}

enum nss_status

_nss_nis_getspnam_r (const char *name, struct spwd *sp,

		     char *buffer, size_t buflen, int *errnop)

{

  if (name == NULL)

    {

      *errnop = EINVAL;

      return NSS_STATUS_UNAVAIL;

    }

  const size_t name_len = strlen (name);

  char *domain;

  if (__glibc_unlikely (yp_get_default_domain (&domain)))

    return NSS_STATUS_UNAVAIL;

  bool adjunct_used = false;

  char *result;

  int len;

  int yperr = yp_match (domain, "shadow.byname", name, name_len, &result,

			&len;;

  if (__builtin_expect (yperr == YPERR_MAP, 0)

      && (_nsl_default_nss () & NSS_FLAG_ADJUNCT_AS_SHADOW))

    {

      free (result);

      yperr = yp_match (domain, "passwd.adjunct.byname", name, name_len,

			&result, &len;;

      adjunct_used = true;

    }

  if (__glibc_unlikely (yperr != YPERR_SUCCESS))

    {

      enum nss_status retval = yperr2nss (yperr);

      if (retval == NSS_STATUS_TRYAGAIN)

	*errnop = errno;

      return retval;

    }

  if (__glibc_unlikely ((size_t) (len + (adjunct_used ? 3 : 1)) > buflen))

    {

      free (result);

      *errnop = ERANGE;

      return NSS_STATUS_TRYAGAIN;

    }

  char *p = strncpy (buffer, result, len);

  if (__builtin_expect (adjunct_used, false))

    /* This is an ugly trick.  The format of passwd.adjunct.byname almost

       matches the shadow.byname format except that the last two fields

       are missing.  Synthesize them by marking them empty.  */

    strcpy (&buffer[len], "::");

  else

    buffer[len] = '\0';

  while (isspace (*p))

    ++p;

  free (result);

  int parse_res = _nss_files_parse_spent (p, sp, (void *) buffer, buflen,

					  errnop);

  if (__glibc_unlikely (parse_res < 1))

    {

      if (parse_res == -1)

	return NSS_STATUS_TRYAGAIN;

      else

	return NSS_STATUS_NOTFOUND;

    }

  return NSS_STATUS_SUCCESS;

}