375 lines
10 KiB
C
375 lines
10 KiB
C
/* Copyright (C) 1998-2002, 2003, 2004 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
|
|
|
|
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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <netdb.h>
|
|
#include <resolv.h>
|
|
#include <stdint.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <arpa/nameser.h>
|
|
#include <not-cancel.h>
|
|
|
|
#include "nscd-client.h"
|
|
#include "nscd_proto.h"
|
|
|
|
int __nss_not_use_nscd_hosts;
|
|
|
|
static int nscd_gethst_r (const char *key, size_t keylen, request_type type,
|
|
struct hostent *resultbuf, char *buffer,
|
|
size_t buflen, struct hostent **result,
|
|
int *h_errnop) internal_function;
|
|
|
|
|
|
int
|
|
__nscd_gethostbyname_r (const char *name, struct hostent *resultbuf,
|
|
char *buffer, size_t buflen, struct hostent **result,
|
|
int *h_errnop)
|
|
{
|
|
request_type reqtype;
|
|
|
|
reqtype = (_res.options & RES_USE_INET6) ? GETHOSTBYNAMEv6 : GETHOSTBYNAME;
|
|
|
|
return nscd_gethst_r (name, strlen (name) + 1, reqtype, resultbuf,
|
|
buffer, buflen, result, h_errnop);
|
|
}
|
|
|
|
|
|
int
|
|
__nscd_gethostbyname2_r (const char *name, int af, struct hostent *resultbuf,
|
|
char *buffer, size_t buflen, struct hostent **result,
|
|
int *h_errnop)
|
|
{
|
|
request_type reqtype;
|
|
|
|
reqtype = af == AF_INET6 ? GETHOSTBYNAMEv6 : GETHOSTBYNAME;
|
|
|
|
return nscd_gethst_r (name, strlen (name) + 1, reqtype, resultbuf,
|
|
buffer, buflen, result, h_errnop);
|
|
}
|
|
|
|
|
|
int
|
|
__nscd_gethostbyaddr_r (const void *addr, socklen_t len, int type,
|
|
struct hostent *resultbuf, char *buffer, size_t buflen,
|
|
struct hostent **result, int *h_errnop)
|
|
{
|
|
request_type reqtype;
|
|
|
|
if (!((len == INADDRSZ && type == AF_INET)
|
|
|| (len == IN6ADDRSZ && type == AF_INET6)))
|
|
/* LEN and TYPE do not match. */
|
|
return -1;
|
|
|
|
reqtype = type == AF_INET6 ? GETHOSTBYADDRv6 : GETHOSTBYADDR;
|
|
|
|
return nscd_gethst_r (addr, len, reqtype, resultbuf, buffer, buflen, result,
|
|
h_errnop);
|
|
}
|
|
|
|
|
|
libc_locked_map_ptr (map_handle);
|
|
/* Note that we only free the structure if necessary. The memory
|
|
mapping is not removed since it is not visible to the malloc
|
|
handling. */
|
|
libc_freeres_fn (gr_map_free)
|
|
{
|
|
if (map_handle.mapped != NO_MAPPING)
|
|
free (map_handle.mapped);
|
|
}
|
|
|
|
|
|
static int
|
|
internal_function
|
|
nscd_gethst_r (const char *key, size_t keylen, request_type type,
|
|
struct hostent *resultbuf, char *buffer, size_t buflen,
|
|
struct hostent **result, int *h_errnop)
|
|
{
|
|
int gc_cycle;
|
|
int nretries = 0;
|
|
|
|
/* If the mapping is available, try to search there instead of
|
|
communicating with the nscd. */
|
|
struct mapped_database *mapped;
|
|
mapped = __nscd_get_map_ref (GETFDHST, "hosts", &map_handle, &gc_cycle);
|
|
|
|
retry:;
|
|
const hst_response_header *hst_resp = NULL;
|
|
const char *h_name = NULL;
|
|
const uint32_t *aliases_len = NULL;
|
|
const char *addr_list = NULL;
|
|
size_t addr_list_len = 0;
|
|
int retval = -1;
|
|
const char *recend = (const char *) ~UINTMAX_C (0);
|
|
int sock = -1;
|
|
if (mapped != NO_MAPPING)
|
|
{
|
|
const struct datahead *found = __nscd_cache_search (type, key, keylen,
|
|
mapped);
|
|
if (found != NULL)
|
|
{
|
|
hst_resp = &found->data[0].hstdata;
|
|
h_name = (char *) (hst_resp + 1);
|
|
aliases_len = (uint32_t *) (h_name + hst_resp->h_name_len);
|
|
addr_list = ((char *) aliases_len
|
|
+ hst_resp->h_aliases_cnt * sizeof (uint32_t));
|
|
addr_list_len = hst_resp->h_addr_list_cnt * INADDRSZ;
|
|
|
|
#ifndef _STRING_ARCH_unaligned
|
|
/* The aliases_len array in the mapped database might very
|
|
well be unaligned. We will access it word-wise so on
|
|
platforms which do not tolerate unaligned accesses we
|
|
need to make an aligned copy. */
|
|
if (((uintptr_t) aliases_len & (__alignof__ (*aliases_len) - 1))
|
|
!= 0)
|
|
{
|
|
uint32_t *tmp = alloca (hst_resp->h_aliases_cnt
|
|
* sizeof (uint32_t));
|
|
aliases_len = memcpy (tmp, aliases_len,
|
|
hst_resp->h_aliases_cnt
|
|
* sizeof (uint32_t));
|
|
}
|
|
#endif
|
|
if (type != GETHOSTBYADDR && type != GETHOSTBYNAME)
|
|
{
|
|
if (hst_resp->h_length == INADDRSZ)
|
|
addr_list += addr_list_len;
|
|
addr_list_len = hst_resp->h_addr_list_cnt * IN6ADDRSZ;
|
|
}
|
|
recend = (const char *) found->data + found->recsize;
|
|
if (__builtin_expect ((const char *) addr_list + addr_list_len
|
|
> recend, 0))
|
|
goto out_close;
|
|
}
|
|
}
|
|
|
|
hst_response_header hst_resp_mem;
|
|
if (hst_resp == NULL)
|
|
{
|
|
sock = __nscd_open_socket (key, keylen, type, &hst_resp_mem,
|
|
sizeof (hst_resp_mem));
|
|
if (sock == -1)
|
|
{
|
|
__nss_not_use_nscd_hosts = 1;
|
|
goto out;;
|
|
}
|
|
|
|
hst_resp = &hst_resp_mem;
|
|
}
|
|
|
|
/* No value found so far. */
|
|
*result = NULL;
|
|
|
|
if (__builtin_expect (hst_resp->found == -1, 0))
|
|
{
|
|
/* The daemon does not cache this database. */
|
|
__nss_not_use_nscd_hosts = 1;
|
|
goto out_close;
|
|
}
|
|
|
|
if (hst_resp->found == 1)
|
|
{
|
|
struct iovec vec[4];
|
|
char *cp = buffer;
|
|
uintptr_t align1;
|
|
uintptr_t align2;
|
|
size_t total_len;
|
|
ssize_t cnt;
|
|
char *ignore;
|
|
int n;
|
|
|
|
/* A first check whether the buffer is sufficiently large is possible. */
|
|
/* Now allocate the buffer the array for the group members. We must
|
|
align the pointer and the base of the h_addr_list pointers. */
|
|
align1 = ((__alignof__ (char *) - (cp - ((char *) 0)))
|
|
& (__alignof__ (char *) - 1));
|
|
align2 = ((__alignof__ (char *) - ((cp + align1 + hst_resp->h_name_len)
|
|
- ((char *) 0)))
|
|
& (__alignof__ (char *) - 1));
|
|
if (buflen < (align1 + hst_resp->h_name_len + align2
|
|
+ ((hst_resp->h_aliases_cnt + hst_resp->h_addr_list_cnt
|
|
+ 2)
|
|
* sizeof (char *))
|
|
+ hst_resp->h_addr_list_cnt * (type == AF_INET
|
|
? INADDRSZ : IN6ADDRSZ)))
|
|
{
|
|
no_room:
|
|
__set_errno (ERANGE);
|
|
retval = ERANGE;
|
|
goto out_close;
|
|
}
|
|
cp += align1;
|
|
|
|
/* Prepare the result as far as we can. */
|
|
resultbuf->h_aliases = (char **) cp;
|
|
cp += (hst_resp->h_aliases_cnt + 1) * sizeof (char *);
|
|
resultbuf->h_addr_list = (char **) cp;
|
|
cp += (hst_resp->h_addr_list_cnt + 1) * sizeof (char *);
|
|
|
|
resultbuf->h_name = cp;
|
|
cp += hst_resp->h_name_len + align2;
|
|
|
|
if (type == GETHOSTBYADDR || type == GETHOSTBYNAME)
|
|
{
|
|
resultbuf->h_addrtype = AF_INET;
|
|
resultbuf->h_length = INADDRSZ;
|
|
}
|
|
else
|
|
{
|
|
resultbuf->h_addrtype = AF_INET6;
|
|
resultbuf->h_length = IN6ADDRSZ;
|
|
}
|
|
for (cnt = 0; cnt < hst_resp->h_addr_list_cnt; ++cnt)
|
|
{
|
|
resultbuf->h_addr_list[cnt] = cp;
|
|
cp += resultbuf->h_length;
|
|
}
|
|
resultbuf->h_addr_list[cnt] = NULL;
|
|
|
|
if (h_name == NULL)
|
|
{
|
|
vec[0].iov_base = resultbuf->h_name;
|
|
vec[0].iov_len = hst_resp->h_name_len;
|
|
total_len = hst_resp->h_name_len;
|
|
n = 1;
|
|
|
|
if (hst_resp->h_aliases_cnt > 0)
|
|
{
|
|
aliases_len = alloca (hst_resp->h_aliases_cnt
|
|
* sizeof (uint32_t));
|
|
vec[n].iov_base = (void *) aliases_len;
|
|
vec[n].iov_len = hst_resp->h_aliases_cnt * sizeof (uint32_t);
|
|
|
|
total_len += hst_resp->h_aliases_cnt * sizeof (uint32_t);
|
|
++n;
|
|
}
|
|
|
|
if (type == GETHOSTBYADDR || type == GETHOSTBYNAME)
|
|
{
|
|
vec[n].iov_base = resultbuf->h_addr_list[0];
|
|
vec[n].iov_len = hst_resp->h_addr_list_cnt * INADDRSZ;
|
|
|
|
total_len += hst_resp->h_addr_list_cnt * INADDRSZ;
|
|
|
|
++n;
|
|
}
|
|
else
|
|
{
|
|
if (hst_resp->h_length == INADDRSZ)
|
|
{
|
|
ignore = alloca (hst_resp->h_addr_list_cnt * INADDRSZ);
|
|
vec[n].iov_base = ignore;
|
|
vec[n].iov_len = hst_resp->h_addr_list_cnt * INADDRSZ;
|
|
|
|
total_len += hst_resp->h_addr_list_cnt * INADDRSZ;
|
|
|
|
++n;
|
|
}
|
|
|
|
vec[n].iov_base = resultbuf->h_addr_list[0];
|
|
vec[n].iov_len = hst_resp->h_addr_list_cnt * IN6ADDRSZ;
|
|
|
|
total_len += hst_resp->h_addr_list_cnt * IN6ADDRSZ;
|
|
|
|
++n;
|
|
}
|
|
|
|
if ((size_t) TEMP_FAILURE_RETRY (__readv (sock, vec, n))
|
|
!= total_len)
|
|
goto out_close;
|
|
}
|
|
else
|
|
{
|
|
memcpy (resultbuf->h_name, h_name, hst_resp->h_name_len);
|
|
memcpy (resultbuf->h_addr_list[0], addr_list, addr_list_len);
|
|
}
|
|
|
|
/* Now we also can read the aliases. */
|
|
total_len = 0;
|
|
for (cnt = 0; cnt < hst_resp->h_aliases_cnt; ++cnt)
|
|
{
|
|
resultbuf->h_aliases[cnt] = cp;
|
|
cp += aliases_len[cnt];
|
|
total_len += aliases_len[cnt];
|
|
}
|
|
resultbuf->h_aliases[cnt] = NULL;
|
|
|
|
if (__builtin_expect ((const char *) addr_list + addr_list_len
|
|
+ total_len > recend, 0))
|
|
goto out_close;
|
|
/* See whether this would exceed the buffer capacity. */
|
|
if (__builtin_expect (cp > buffer + buflen, 0))
|
|
goto no_room;
|
|
|
|
/* And finally read the aliases. */
|
|
if (addr_list == NULL)
|
|
{
|
|
if ((size_t) TEMP_FAILURE_RETRY (__read (sock,
|
|
resultbuf->h_aliases[0],
|
|
total_len)) == total_len)
|
|
{
|
|
retval = 0;
|
|
*result = resultbuf;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
memcpy (resultbuf->h_aliases[0],
|
|
(const char *) addr_list + addr_list_len, total_len);
|
|
|
|
retval = 0;
|
|
*result = resultbuf;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
/* Store the error number. */
|
|
*h_errnop = hst_resp->error;
|
|
|
|
/* The `errno' to some value != ERANGE. */
|
|
__set_errno (ENOENT);
|
|
/* Even though we have not found anything, the result is zero. */
|
|
retval = 0;
|
|
}
|
|
|
|
out_close:
|
|
if (sock != -1)
|
|
close_not_cancel_no_status (sock);
|
|
out:
|
|
if (__nscd_drop_map_ref (mapped, &gc_cycle) != 0 && retval != -1)
|
|
{
|
|
/* When we come here this means there has been a GC cycle while we
|
|
were looking for the data. This means the data might have been
|
|
inconsistent. Retry if possible. */
|
|
if ((gc_cycle & 1) != 0 || ++nretries == 5)
|
|
{
|
|
/* nscd is just running gc now. Disable using the mapping. */
|
|
__nscd_unmap (mapped);
|
|
mapped = NO_MAPPING;
|
|
}
|
|
|
|
goto retry;
|
|
}
|
|
|
|
return retval;
|
|
}
|