glibc/nscd/nscd_getgr_r.c

/* Copyright (C) 1998 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Thorsten Kukuk <kukuk@uni-paderborn.de>, 1998.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 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
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <grp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>

#include "nscd.h"
#include "nscd_proto.h"

int __nss_not_use_nscd_group;

static int __nscd_getgr_r (const char *key, request_type type,
			   struct group *resultbuf, char *buffer,
			   size_t buflen);

int
__nscd_getgrnam_r (const char *name, struct group *resultbuf, char *buffer,
		   size_t buflen)
{
  if (name == NULL)
    return 1;

  return __nscd_getgr_r (name, GETGRBYNAME, resultbuf, buffer, buflen);
}

int
__nscd_getgrgid_r (gid_t gid, struct group *resultbuf, char *buffer,
		   size_t buflen)
{
  char *p = buffer;
  int plen;

  plen = snprintf (buffer, buflen, "%d", gid);
  if (plen == -1)
    {
      __set_errno (ERANGE);
      return -1;
    }
  p = buffer + plen + 1;

  return __nscd_getgr_r (buffer, GETGRBYGID, resultbuf, p, buflen - plen -1);
}

/* Create a socket connected to a name. */
static int
nscd_open_socket (void)
{
  struct sockaddr_un addr;
  int sock;
  int saved_errno = errno;

  sock = socket (PF_UNIX, SOCK_STREAM, 0);
  if (sock < 0)
    {
      __set_errno (saved_errno);
      return -1;
    }

  addr.sun_family = AF_UNIX;
  strcpy (addr.sun_path, _PATH_NSCDSOCKET);
  if (connect (sock, (struct sockaddr *) &addr, sizeof (addr)) < 0)
    {
      close (sock);
      __set_errno (saved_errno);
      return -1;
    }

  return sock;
}

static int
__nscd_getgr_r (const char *key, request_type type, struct group *resultbuf,
		char *buffer, size_t buflen)
{
  int sock = nscd_open_socket ();
  request_header req;
  gr_response_header gr_resp;
  ssize_t nbytes;

  if (sock == -1)
    {
      /* Returning two signals that contacting the daemon failed.  */
      __nss_not_use_nscd_group = 1;
      return 1;
    }

  req.version = NSCD_VERSION;
  req.type = type;
  req.key_len = strlen (key);
  nbytes = write (sock, &req, sizeof (request_header));
  if (nbytes != sizeof (request_header))
    {
      close (sock);
      return 1;
    }

  nbytes = write (sock, key, req.key_len);
  if (nbytes != req.key_len)
    {
      close (sock);
      return 1;
    }

  nbytes = read (sock, &gr_resp, sizeof (gr_response_header));
  if (nbytes != sizeof (gr_response_header))
    {
      close (sock);
      return 1;
    }

  if (gr_resp.found == -1)
    {
      /* The daemon does not cache this database.  */
      close (sock);
      __nss_not_use_nscd_group = 1;
      return 1;
    }

  if (gr_resp.found == 1)
    {
      size_t i;
      char *p = buffer;

      if (buflen < gr_resp.gr_name_len + 1)
	{
	  __set_errno (ERANGE);
	  close (sock);
	  return -1;
	}
      resultbuf->gr_name = p;
      p += gr_resp.gr_name_len + 1;
      buflen -= (gr_resp.gr_name_len + 1);
      nbytes = read (sock, resultbuf->gr_name, gr_resp.gr_name_len);
      if (nbytes != gr_resp.gr_name_len)
	{
	  close (sock);
	  return 1;
	}
      resultbuf->gr_name[gr_resp.gr_name_len] = '\0';

      if (buflen < gr_resp.gr_passwd_len + 1)
	{
	  __set_errno (ERANGE);
	  close (sock);
	  return -1;
	}
      resultbuf->gr_passwd = p;
      p += gr_resp.gr_passwd_len + 1;
      buflen -= (gr_resp.gr_passwd_len + 1);
      nbytes = read (sock, resultbuf->gr_passwd, gr_resp.gr_passwd_len);
      if (nbytes != gr_resp.gr_passwd_len)
	{
	  close (sock);
	  return 1;
	}
      resultbuf->gr_passwd[gr_resp.gr_passwd_len] = '\0';

      resultbuf->gr_gid = gr_resp.gr_gid;

      if (buflen < ((gr_resp.gr_mem_len + 1) * sizeof (char *)))
	{
	  __set_errno (ERANGE);
	  close (sock);
	  return -1;
	}
      resultbuf->gr_mem = (char **)p;
      p += ((gr_resp.gr_mem_len + 1) * sizeof (char *));
      buflen -= ((gr_resp.gr_mem_len + 1) * sizeof (char *));

      resultbuf->gr_mem[gr_resp.gr_mem_len] = NULL;

      for (i = 0; i < gr_resp.gr_mem_len; ++i)
	{
	  size_t len;
	  nbytes = read (sock, &len, sizeof (len));
	  if (nbytes != sizeof (len))
	    {
	      close (sock);
	      return 1;
	    }

	  if (buflen < (len + 1))
	    {
	      __set_errno (ERANGE);
	      close (sock);
	      return -1;
	    }
	  resultbuf->gr_mem[i] = p;
	  p += len + 1;
	  buflen -= (len + 1);
	  nbytes = read (sock, resultbuf->gr_mem[i], len);
	  resultbuf->gr_mem[i][len] = '\0';
	  if (nbytes != len)
	    {
	      close (sock);
	      return 1;
	    }
	}
      close (sock);
      return 0;
    }
  else
    {
      close (sock);
      return -1;
    }
}