/*

   ethers.c - NSS lookup functions for ethers database

   Copyright (C) 2006 West Consulting

   Copyright (C) 2006-2015 Arthur de Jong

   Copyright (C) 2010 Symas Corporation

   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, write to the Free Software

   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

   02110-1301 USA

*/

#include "config.h"

#include <string.h>

#include <errno.h>

#include "prototypes.h"

#include "common.h"

#include "compat/attrs.h"

/* read an ethernet entry from the stream */

static nss_status_t read_etherent(TFILE *fp, struct etherent *result,

                                  char *buffer, size_t buflen, int *errnop)

{

  int32_t tmpint32;

  size_t bufptr = 0;

  memset(result, 0, sizeof(struct etherent));

  READ_BUF_STRING(fp, result->e_name);

  READ(fp, &(result->e_addr), sizeof(uint8_t[6]));

  return NSS_STATUS_SUCCESS;

}

#ifdef NSS_FLAVOUR_GLIBC

/* map a hostname to the corresponding ethernet address */

nss_status_t NSS_NAME(gethostton_r)(const char *name,

                                    struct etherent *result, char *buffer,

                                    size_t buflen, int *errnop)

{

  NSS_GETONE(NSLCD_ACTION_ETHER_BYNAME,

             WRITE_STRING(fp, name),

             read_etherent(fp, result, buffer, buflen, errnop));

}

/* map an ethernet address to the corresponding hostname */

nss_status_t NSS_NAME(getntohost_r)(const struct ether_addr *addr,

                                    struct etherent *result, char *buffer,

                                    size_t buflen, int *errnop)

{

  NSS_GETONE(NSLCD_ACTION_ETHER_BYETHER,

             WRITE(fp, addr, sizeof(uint8_t[6])),

             read_etherent(fp, result, buffer, buflen, errnop));

}

/* thread-local file pointer to an ongoing request */

static TLS TFILE *etherentfp;

/* open a connection to read all ether entries */

nss_status_t NSS_NAME(setetherent)(int UNUSED(stayopen))

{

  NSS_SETENT(etherentfp);

}

/* read a single ethernet entry from the stream */

nss_status_t NSS_NAME(getetherent_r)(struct etherent *result,

                                     char *buffer, size_t buflen, int *errnop)

{

  NSS_GETENT(etherentfp, NSLCD_ACTION_ETHER_ALL,

             read_etherent(etherentfp, result, buffer, buflen, errnop));

}

/* close the stream opened with setetherent() above */

nss_status_t NSS_NAME(endetherent)(void)

{

  NSS_ENDENT(etherentfp);

}

#endif /* NSS_FLAVOUR_GLIBC */

#ifdef NSS_FLAVOUR_SOLARIS

/* we disable NSS_BUFCHECK because these functions do not use the buffer */

#undef NSS_BUFCHECK

#define NSS_BUFCHECK ;

/* provide a fallback definition */

#ifndef NSS_BUFLEN_ETHERS

#define NSS_BUFLEN_ETHERS HOST_NAME_MAX

#endif /* NSS_BUFLEN_ETHERS */

#ifdef HAVE_STRUCT_NSS_XBYY_ARGS_RETURNLEN

static char *etherent2str(struct etherent *result, char *buffer,

                          size_t buflen)

{

  int res;

  res = snprintf(buffer, buflen, "%s %s", ether_ntoa(&result->e_addr),

                 result->e_name);

  if ((res < 0) || (res >= (int)buflen))

    return NULL;

  return buffer;

}

#endif /* HAVE_STRUCT_NSS_XBYY_ARGS_RETURNLEN */

static nss_status_t read_result(TFILE *fp, nss_XbyY_args_t *args, int wantname)

{

  struct etherent result;

  char buffer[NSS_BUFLEN_ETHERS];

  nss_status_t retv;

  /* read the result entry from the stream */

  retv = read_etherent(fp, &result, buffer, sizeof(buffer), &args->erange);

  if (retv != NSS_STATUS_SUCCESS)

    return retv;

#ifdef HAVE_STRUCT_NSS_XBYY_ARGS_RETURNLEN

  /* try to return in string format if requested */

  if ((args->buf.buffer != NULL) && (args->buf.buflen > 0))

  {

    if (etherent2str(&result, args->buf.buffer, args->buf.buflen) == NULL)

    {

      args->erange = 1;

      return NSS_NOTFOUND;

    }

    args->returnval = args->buf.buffer;

    args->returnlen = strlen(args->returnval);

    return NSS_SUCCESS;

  }

#endif /* HAVE_STRUCT_NSS_XBYY_ARGS_RETURNLEN */

  /* return the result entry */

  if (wantname)

  {

    /* we expect the buffer to have enough room for the name (buflen == 0) */

    strcpy(args->buf.buffer, result.e_name);

    args->returnval = args->buf.buffer;

  }

  else /* address */

  {

    memcpy(args->buf.result, &result.e_addr, sizeof(result.e_addr));

    args->returnval = args->buf.result;

  }

  return NSS_SUCCESS;

}

/* map a hostname to the corresponding ethernet address */

static nss_status_t ethers_gethostton(nss_backend_t UNUSED(*be), void *args)

{

  NSS_GETONE(NSLCD_ACTION_ETHER_BYNAME,

             WRITE_STRING(fp, NSS_ARGS(args)->key.name),

             read_result(fp, args, 0));

}

/* map an ethernet address to the corresponding hostname */

static nss_status_t ethers_getntohost(nss_backend_t UNUSED(*be), void *args)

{

  struct ether_addr *addr = (struct ether_addr *)(NSS_ARGS(args)->key.ether);

  NSS_GETONE(NSLCD_ACTION_ETHER_BYETHER,

             WRITE(fp, addr, sizeof(uint8_t[6])),

             read_result(fp, args, 1));

}

static nss_backend_op_t ethers_ops[] = {

  nss_ldap_destructor,

  ethers_gethostton,

  ethers_getntohost

};

nss_backend_t *NSS_NAME(ethers_constr)(const char UNUSED(*db_name),

                                       const char UNUSED(*src_name),

                                       const char UNUSED(*cfg_args))

{

  return nss_ldap_constructor(ethers_ops, sizeof(ethers_ops));

}

#endif /* NSS_FLAVOUR_SOLARIS */