glibc/nis/nss_nisplus/nisplus-proto.c

442 lines
10 KiB
C

/* Copyright (C) 1997-2020 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 <atomic.h>
#include <ctype.h>
#include <errno.h>
#include <netdb.h>
#include <nss.h>
#include <string.h>
#include <rpcsvc/nis.h>
#include <libc-lock.h>
#include "nss-nisplus.h"
__libc_lock_define_initialized (static, lock)
static nis_result *result;
static nis_name tablename_val;
static u_long tablename_len;
#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)
static int
_nss_nisplus_parse_protoent (nis_result *result, struct protoent *proto,
char *buffer, size_t buflen, int *errnop)
{
char *first_unused = buffer;
size_t room_left = buflen;
unsigned int i;
if (result == NULL)
return 0;
if ((result->status != NIS_SUCCESS && result->status != NIS_S_SUCCESS)
|| __type_of (NIS_RES_OBJECT (result)) != NIS_ENTRY_OBJ
|| strcmp (NIS_RES_OBJECT (result)->EN_data.en_type,
"protocols_tbl") != 0
|| NIS_RES_OBJECT (result)->EN_data.en_cols.en_cols_len < 3)
return 0;
/* Generate the protocols entry format and use the normal parser */
if (NISENTRYLEN (0, 0, result) + 1 > room_left)
{
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';
proto->p_name = first_unused;
size_t len = strlen (first_unused) + 1;
room_left -= len;
first_unused += len;
proto->p_proto = atoi (NISENTRYVAL (0, 2, result));
/* XXX Rewrite at some point to allocate the array first and then
copy the strings. It wasteful to first concatenate the strings
to just split them again later. */
char *line = first_unused;
for (i = 0; i < NIS_RES_NUMOBJ (result); ++i)
{
if (strcmp (NISENTRYVAL (i, 1, result), proto->p_name) != 0)
{
if (NISENTRYLEN (i, 1, result) + 2 > room_left)
goto no_more_room;
*first_unused++ = ' ';
first_unused = __stpncpy (first_unused, NISENTRYVAL (i, 1, result),
NISENTRYLEN (i, 1, result));
room_left -= NISENTRYLEN (i, 1, result) + 1;
}
}
*first_unused++ = '\0';
/* 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 + sizeof (char *))
goto no_more_room;
first_unused += adjust;
room_left -= adjust;
proto->p_aliases = (char **) first_unused;
/* For the terminating NULL pointer. */
room_left -= sizeof (char *);
i = 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 *);
proto->p_aliases[i++] = line;
while (*line != '\0' && *line != ' ')
++line;
if (*line == ' ')
*line++ = '\0';
}
proto->p_aliases[i] = NULL;
return 1;
}
static enum nss_status
_nss_create_tablename (int *errnop)
{
if (tablename_val == NULL)
{
const char *local_dir = nis_local_directory ();
size_t local_dir_len = strlen (local_dir);
static const char prefix[] = "protocols.org_dir.";
char *p = malloc (sizeof (prefix) + local_dir_len);
if (p == NULL)
{
*errnop = errno;
return NSS_STATUS_TRYAGAIN;
}
memcpy (__stpcpy (p, prefix), local_dir, local_dir_len + 1);
tablename_len = sizeof (prefix) - 1 + local_dir_len;
atomic_write_barrier ();
tablename_val = p;
}
return NSS_STATUS_SUCCESS;
}
enum nss_status
_nss_nisplus_setprotoent (int stayopen)
{
enum nss_status status = NSS_STATUS_SUCCESS;
__libc_lock_lock (lock);
if (result != NULL)
{
nis_freeresult (result);
result = NULL;
}
if (tablename_val == NULL)
{
int err;
status = _nss_create_tablename (&err);
}
__libc_lock_unlock (lock);
return status;
}
enum nss_status
_nss_nisplus_endprotoent (void)
{
__libc_lock_lock (lock);
if (result != NULL)
{
nis_freeresult (result);
result = NULL;
}
__libc_lock_unlock (lock);
return NSS_STATUS_SUCCESS;
}
static enum nss_status
internal_nisplus_getprotoent_r (struct protoent *proto, char *buffer,
size_t buflen, int *errnop)
{
int parse_res;
/* Get the next entry until we found a correct one. */
do
{
nis_result *saved_res;
if (result == NULL)
{
saved_res = NULL;
if (tablename_val == NULL)
{
enum nss_status status = _nss_create_tablename (errnop);
if (status != NSS_STATUS_SUCCESS)
return status;
}
result = nis_first_entry (tablename_val);
if (result == NULL)
{
*errnop = errno;
return NSS_STATUS_TRYAGAIN;
}
if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
return niserr2nss (result->status);
}
else
{
saved_res = result;
result = nis_next_entry (tablename_val, &result->cookie);
if (result == NULL)
{
*errnop = errno;
return NSS_STATUS_TRYAGAIN;
}
if (niserr2nss (result->status) != NSS_STATUS_SUCCESS)
{
nis_freeresult (saved_res);
return niserr2nss (result->status);
}
}
parse_res = _nss_nisplus_parse_protoent (result, proto, buffer,
buflen, errnop);
if (parse_res == -1)
{
nis_freeresult (result);
result = saved_res;
*errnop = ERANGE;
return NSS_STATUS_TRYAGAIN;
}
else
{
if (saved_res)
nis_freeresult (saved_res);
}
}
while (!parse_res);
return NSS_STATUS_SUCCESS;
}
enum nss_status
_nss_nisplus_getprotoent_r (struct protoent *result, char *buffer,
size_t buflen, int *errnop)
{
int status;
__libc_lock_lock (lock);
status = internal_nisplus_getprotoent_r (result, buffer, buflen, errnop);
__libc_lock_unlock (lock);
return status;
}
enum nss_status
_nss_nisplus_getprotobyname_r (const char *name, struct protoent *proto,
char *buffer, size_t buflen, int *errnop)
{
int parse_res;
if (tablename_val == NULL)
{
__libc_lock_lock (lock);
enum nss_status status = _nss_create_tablename (errnop);
__libc_lock_unlock (lock);
if (status != NSS_STATUS_SUCCESS)
return status;
}
if (name == NULL)
return NSS_STATUS_NOTFOUND;
char buf[strlen (name) + 10 + tablename_len];
int olderr = errno;
/* Search at first in the alias list, and use the correct name
for the next search */
snprintf (buf, sizeof (buf), "[name=%s],%s", name, tablename_val);
nis_result *result = nis_list (buf, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
if (result != NULL)
{
char *bufptr = buf;
/* If we did not find it, try it as original name. But if the
database is correct, we should find it in the first case, too */
if ((result->status != NIS_SUCCESS
&& result->status != NIS_S_SUCCESS)
|| __type_of (result->objects.objects_val) != NIS_ENTRY_OBJ
|| strcmp (result->objects.objects_val->EN_data.en_type,
"protocols_tbl") != 0
|| result->objects.objects_val->EN_data.en_cols.en_cols_len < 3)
snprintf (buf, sizeof (buf), "[cname=%s],%s", name, tablename_val);
else
{
/* We need to allocate a new buffer since there is no
guarantee the returned name has a length limit. */
const char *entryval = NISENTRYVAL (0, 0, result);
size_t buflen = strlen (entryval) + 10 + tablename_len;
bufptr = alloca (buflen);
snprintf (bufptr, buflen, "[cname=%s],%s",
entryval, tablename_val);
}
nis_freeresult (result);
result = nis_list (bufptr, FOLLOW_PATH | FOLLOW_LINKS, NULL, NULL);
}
if (result == NULL)
{
__set_errno (ENOMEM);
return NSS_STATUS_TRYAGAIN;
}
if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS))
{
enum nss_status status = niserr2nss (result->status);
__set_errno (olderr);
nis_freeresult (result);
return status;
}
parse_res = _nss_nisplus_parse_protoent (result, proto, buffer, buflen,
errnop);
nis_freeresult (result);
if (parse_res < 1)
{
if (parse_res == -1)
{
*errnop = ERANGE;
return NSS_STATUS_TRYAGAIN;
}
else
{
__set_errno (olderr);
return NSS_STATUS_NOTFOUND;
}
}
return NSS_STATUS_SUCCESS;
}
enum nss_status
_nss_nisplus_getprotobynumber_r (const int number, struct protoent *proto,
char *buffer, size_t buflen, int *errnop)
{
if (tablename_val == NULL)
{
__libc_lock_lock (lock);
enum nss_status status = _nss_create_tablename (errnop);
__libc_lock_unlock (lock);
if (status != NSS_STATUS_SUCCESS)
return status;
}
char buf[12 + 3 * sizeof (number) + tablename_len];
int olderr = errno;
snprintf (buf, sizeof (buf), "[number=%d],%s", number, tablename_val);
nis_result *result = nis_list (buf, FOLLOW_LINKS | FOLLOW_PATH, NULL, NULL);
if (result == NULL)
{
__set_errno (ENOMEM);
return NSS_STATUS_TRYAGAIN;
}
if (__glibc_unlikely (niserr2nss (result->status) != NSS_STATUS_SUCCESS))
{
enum nss_status status = niserr2nss (result->status);
__set_errno (olderr);
nis_freeresult (result);
return status;
}
int parse_res = _nss_nisplus_parse_protoent (result, proto, buffer, buflen,
errnop);
nis_freeresult (result);
if (parse_res < 1)
{
if (parse_res == -1)
{
*errnop = ERANGE;
return NSS_STATUS_TRYAGAIN;
}
else
{
__set_errno (olderr);
return NSS_STATUS_NOTFOUND;
}
}
return NSS_STATUS_SUCCESS;
}