glibc/nis/nss_nisplus/nisplus-parser.c

/* Copyright (C) 1997-2019 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.

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

#include <pwd.h>
#include <ctype.h>
#include <errno.h>
#include <string.h>
#include <rpcsvc/nis.h>

#include "nisplus-parser.h"

#define NISENTRYVAL(idx, col, res) \
        (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)

#define NISENTRYLEN(idx, col, res) \
        (NIS_RES_OBJECT (res)[idx].EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)

#define NISOBJVAL(col, obj) \
  ((obj)->EN_data.en_cols.en_cols_val[col].ec_value.ec_value_val)

#define NISOBJLEN(col, obj) \
  ((obj)->EN_data.en_cols.en_cols_val[col].ec_value.ec_value_len)


int
_nss_nisplus_parse_pwent (nis_result *result, struct passwd *pw,
			  char *buffer, size_t buflen, int *errnop)
{
  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
      || NIS_RES_NUMOBJ (result) != 1
      || __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
      || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type, "passwd_tbl") != 0
      || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 7)
    return 0;

  nis_object *obj = NIS_RES_OBJECT (result);
  char *first_unused = buffer;
  size_t room_left = buflen;
  size_t len;

  if (NISOBJLEN (0, obj) >= room_left)
    {
      /* The line is too long for our buffer.  */
    no_more_room:
      *errnop = ERANGE;
      return -1;
    }

  strncpy (first_unused, NISOBJVAL (0, obj), NISOBJLEN (0, obj));
  first_unused[NISOBJLEN (0, obj)] = '\0';
  len = strlen (first_unused);
  if (len == 0) /* No name ? Should never happen, database is corrupt */
    return 0;
  pw->pw_name = first_unused;
  room_left -= len + 1;
  first_unused += len + 1;

  if (NISOBJLEN (1, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (1, obj), NISOBJLEN (1, obj));
  first_unused[NISOBJLEN (1, obj)] = '\0';
  pw->pw_passwd = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  char *numstr = NISOBJVAL (2, obj);
  len = NISOBJLEN (2, obj);
  if (len == 0 || numstr[len - 1] != '\0')
    {
      if (len >= room_left)
	goto no_more_room;

      strncpy (first_unused, numstr, len);
      first_unused[len] = '\0';
      numstr = first_unused;
    }
  if (numstr[0] == '\0')
    /* If we don't have a uid, it's an invalid shadow entry.  */
    return 0;
  pw->pw_uid = strtoul (numstr, NULL, 10);

  numstr = NISOBJVAL (3, obj);
  len = NISOBJLEN (3, obj);
  if (len == 0 || numstr[len - 1] != '\0')
    {
      if (len >= room_left)
	goto no_more_room;

      strncpy (first_unused, numstr, len);
      first_unused[len] = '\0';
      numstr = first_unused;
    }
  if (numstr[0] == '\0')
    /* If we don't have a gid, it's an invalid shadow entry.  */
    return 0;
  pw->pw_gid = strtoul (numstr, NULL, 10);

  if (NISOBJLEN(4, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (4, obj), NISOBJLEN (4, obj));
  first_unused[NISOBJLEN (4, obj)] = '\0';
  pw->pw_gecos = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  if (NISOBJLEN (5, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (5, obj), NISOBJLEN (5, obj));
  first_unused[NISOBJLEN (5, obj)] = '\0';
  pw->pw_dir = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  if (NISOBJLEN (6, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (6, obj), NISOBJLEN (6, obj));
  first_unused[NISOBJLEN (6, obj)] = '\0';
  pw->pw_shell = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  return 1;
}


int
_nss_nisplus_parse_grent (nis_result *result, struct group *gr,
			  char *buffer, size_t buflen, int *errnop)
{
  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
      || __type_of(NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
      || strcmp (NIS_RES_OBJECT (result)[0].EN_data.en_type, "group_tbl") != 0
      || NIS_RES_OBJECT (result)[0].EN_data.en_cols.en_cols_len < 4)
    return 0;

  nis_object *obj = NIS_RES_OBJECT (result);
  char *first_unused = buffer;
  size_t room_left = buflen;
  char *line;
  int count;
  size_t len;

  if (NISOBJLEN (0, obj) >= room_left)
    {
      /* The line is too long for our buffer.  */
    no_more_room:
      *errnop = ERANGE;
      return -1;
    }

  strncpy (first_unused, NISOBJVAL (0, obj), NISOBJLEN (0, obj));
  first_unused[NISOBJLEN (0, obj)] = '\0';
  len = strlen (first_unused);
  if (len == 0) /* group table is corrupt */
    return 0;
  gr->gr_name = first_unused;
  room_left -= len + 1;
  first_unused += len + 1;

  if (NISOBJLEN (1, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (1, obj), NISOBJLEN (1, obj));
  first_unused[NISOBJLEN (1, obj)] = '\0';
  gr->gr_passwd = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  char *numstr = NISOBJVAL (2, obj);
  len = NISOBJLEN (2, obj);
  if (len == 0 || numstr[len - 1] != '\0')
    {
      if (len >= room_left)
	goto no_more_room;

      strncpy (first_unused, numstr, len);
      first_unused[len] = '\0';
      numstr = first_unused;
    }
  if (numstr[0] == '\0')
    /* We should always have a gid.  */
    return 0;
  gr->gr_gid = strtoul (numstr, NULL, 10);

  if (NISOBJLEN (3, obj) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISOBJVAL (3, obj), NISOBJLEN (3, obj));
  first_unused[NISOBJLEN (3, obj)] = '\0';
  line = first_unused;
  len = strlen (line);
  room_left -= len + 1;
  first_unused += len + 1;
  /* Adjust the pointer so it is aligned for
     storing pointers.  */
  size_t adjust = ((__alignof__ (char *)
		    - (first_unused - (char *) 0) % __alignof__ (char *))
		   % __alignof__ (char *));
  if (room_left < adjust)
    goto no_more_room;
  first_unused += adjust;
  room_left -= adjust;
  gr->gr_mem = (char **) first_unused;

  count = 0;
  while (*line != '\0')
    {
      /* Skip leading blanks.  */
      while (isspace (*line))
	++line;

      if (*line == '\0')
	break;

      if (room_left < sizeof (char *))
	goto no_more_room;
      room_left -= sizeof (char *);
      gr->gr_mem[count++] = line;

      while (*line != '\0' && *line != ',' && !isspace (*line))
	++line;

      if (*line == ',' || isspace (*line))
	{
	  int is = isspace (*line);

	  *line++ = '\0';
	  if (is)
	    while (*line != '\0' && (*line == ',' || isspace (*line)))
	      ++line;
	}
    }
  if (room_left < sizeof (char *))
    goto no_more_room;
  room_left -= sizeof (char *);
  gr->gr_mem[count] = NULL;

  return 1;
}


int
_nss_nisplus_parse_spent (nis_result *result, struct spwd *sp,
			  char *buffer, size_t buflen, int *errnop)
{
  char *first_unused = buffer;
  size_t room_left = buflen;
  size_t len;

  if (result == NULL)
    return 0;

  if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
      || NIS_RES_NUMOBJ (result) != 1
      || __type_of(NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
      || strcmp (NIS_RES_OBJECT (result)->EN_data.en_type, "passwd_tbl") != 0
      || NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 8)
    return 0;

  if (NISENTRYLEN (0, 0, result) >= room_left)
    {
      /* The line is too long for our buffer.  */
    no_more_room:
      *errnop = ERANGE;
      return -1;
    }

  strncpy (first_unused, NISENTRYVAL (0, 0, result),
	   NISENTRYLEN (0, 0, result));
  first_unused[NISENTRYLEN (0, 0, result)] = '\0';
  len = strlen (first_unused);
  if (len == 0)
    return 0;
  sp->sp_namp = first_unused;
  room_left -= len + 1;
  first_unused += len + 1;

  if (NISENTRYLEN (0, 1, result) >= room_left)
    goto no_more_room;

  strncpy (first_unused, NISENTRYVAL (0, 1, result),
	   NISENTRYLEN (0, 1, result));
  first_unused[NISENTRYLEN (0, 1, result)] = '\0';
  sp->sp_pwdp = first_unused;
  len = strlen (first_unused);
  room_left -= len + 1;
  first_unused += len + 1;

  sp->sp_lstchg = sp->sp_min = sp->sp_max = sp->sp_warn = sp->sp_inact =
    sp->sp_expire = -1;
  sp->sp_flag = ~0ul;

  if (NISENTRYLEN (0, 7, result) > 0)
    {
      char *line = NISENTRYVAL (0, 7, result);
      char *cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_lstchg = atol (line);

      line = cp;
      cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_min = atol (line);

      line = cp;
      cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_max = atol (line);

      line = cp;
      cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_warn = atol (line);

      line = cp;
      cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_inact = atol (line);

      line = cp;
      cp = strchr (line, ':');
      if (cp == NULL)
	return 1;
      *cp++ = '\0';
      if (*line)
	sp->sp_expire = atol (line);

      line = cp;
      if (line == NULL)
	return 1;
      if (*line)
	sp->sp_flag = atol (line);
    }

  return 1;
}