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/* Copyright (C) 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by H.J. Lu <hjl@gnu.ai.mit.edu>, 1997.
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. */
/*
* disallow names consisting only of digits/dots, unless
* they end in a dot.
*/
if (isdigit (name[0]) || (isxdigit (name[0]) || name[0] == ':'))
{
const char *cp;
char *hostname;
struct hostent *host;
typedef unsigned char host_addr_t [16];
host_addr_t *host_addr;
typedef char *host_addr_list_t [2];
host_addr_list_t *host_aliases;
host_addr_list_t *h_addr_ptrs;
size_t size_needed;
int addr_size;
#ifndef HAVE_AF
int af = -1;
#endif
switch (af)
{
case AF_INET:
addr_size = INADDRSZ;
break;
case AF_INET6:
addr_size = IN6ADDRSZ;
break;
default:
af = (_res.options & RES_USE_INET6) ? AF_INET6 : AF_INET;
addr_size = (af == AF_INET6 ) ? IN6ADDRSZ : INADDRSZ;
break;
}
size_needed = (sizeof (*host) + sizeof (*host_addr)
+ sizeof (*host_aliases) + sizeof (*h_addr_ptrs)
+ strlen (name) + 1);
#ifdef HAVE_LOOKUP_BUFFER
if (buflen < size_needed)
{
__set_errno (ERANGE);
goto done;
}
#else
if (buffer_size < size_needed)
{
char *new_buf;
buffer_size = size_needed;
new_buf = realloc (buffer, buffer_size);
if (new_buf == NULL)
{
save = errno;
free (buffer);
buffer = NULL;
buffer_size = 0;
__set_errno (save);
result = (struct hostent *) NULL;
goto done;
}
buffer = new_buf;
}
#endif /* HAVE_LOOKUP_BUFFER */
memset (buffer, 0, size_needed);
host = (struct hostent *) buffer;
host_addr = (host_addr_t *) ((char *) host + sizeof (*host));
host_aliases = (host_addr_list_t *)
((char *) host_addr + sizeof (*host_addr));
h_addr_ptrs = (host_addr_list_t *)
((char *) host_aliases + sizeof (*host_aliases));
hostname = (char *) h_addr_ptrs + sizeof (*h_addr_ptrs);
if (isdigit (name[0]))
{
for (cp = name;; ++cp)
{
if (!*cp)
{
if (*--cp == '.') break;
/* All-numeric, no dot at the end. Fake up a hostent as if
we'd actually done a lookup. What if someone types
255.255.255.255? The test below will succeed
spuriously... ??? */
if (inet_pton (af, name, host_addr) <= 0)
{
__set_h_errno (HOST_NOT_FOUND);
#ifndef HAVE_LOOKUP_BUFFER
result = (struct hostent *) NULL;
#endif
goto done;
}
strcpy (hostname, name);
host->h_name = hostname;
host->h_aliases = *host_aliases;
(*host_aliases)[0] = NULL;
(*h_addr_ptrs)[0] = (char *)host_addr;
(*h_addr_ptrs)[1] = (char *)0;
host->h_addr_list = *h_addr_ptrs;
if (_res.options & RES_USE_INET6 && af == AF_INET)
{
/* We need to change the IP v4 address into the
IP v6 address. */
char tmp[INADDRSZ], *p = (char *) host_addr;
int i;
/* Save a copy of the IP v4 address. */
memcpy (tmp, host_addr, INADDRSZ);
/* Mark this ipv6 addr as a mapped ipv4. */
for (i = 0; i < 10; i++)
*p++ = 0x00;
*p++ = 0xff;
*p++ = 0xff;
/* Copy the IP v4 address. */
memcpy (p, tmp, INADDRSZ);
host->h_addrtype = AF_INET6;
host->h_length = IN6ADDRSZ;
}
else
{
host->h_addrtype = af;
host->h_length = addr_size;
}
__set_h_errno (NETDB_SUCCESS);
#ifdef HAVE_LOOKUP_BUFFER
status = NSS_STATUS_SUCCESS;
#else
result = host;
#endif
goto done;
}
if (!isdigit (*cp) && *cp != '.') break;
}
}
if ((isxdigit (name[0]) && strchr (name, ':') != NULL)
|| name[0] == ':')
{
const char *cp;
char *hostname;
struct hostent *host;
typedef unsigned char host_addr_t [16];
host_addr_t *host_addr;
typedef char *host_addr_list_t [2];
host_addr_list_t *host_aliases;
host_addr_list_t *h_addr_ptrs;
size_t size_needed;
int addr_size;
#ifndef HAVE_AF
int af = -1;
#endif
switch (af)
{
case AF_INET:
addr_size = INADDRSZ;
break;
case AF_INET6:
addr_size = IN6ADDRSZ;
break;
default:
af = (_res.options & RES_USE_INET6) ? AF_INET6 : AF_INET;
addr_size = (af == AF_INET6 ) ? IN6ADDRSZ : INADDRSZ;
break;
}
size_needed = (sizeof (*host) + sizeof (*host_addr)
+ sizeof (*host_aliases) + sizeof (*h_addr_ptrs)
+ strlen (name) + 1);
#ifdef HAVE_LOOKUP_BUFFER
if (buflen < size_needed)
{
__set_errno (ERANGE);
goto done;
}
#else
if (buffer_size < size_needed)
{
char *new_buf;
buffer_size = size_needed;
new_buf = realloc (buffer, buffer_size);
if (new_buf == NULL)
{
save = errno;
free (buffer);
__set_errno (save);
buffer = NULL;
buffer_size = 0;
result = (struct hostent *) NULL;
goto done;
}
buffer = new_buf;
}
#endif /* HAVE_LOOKUP_BUFFER */
memset (buffer, 0, size_needed);
host = (struct hostent *) buffer;
host_addr = (host_addr_t *) ((char *) host + sizeof (*host));
host_aliases = (host_addr_list_t *)
((char *) host_addr + sizeof (*host_addr));
h_addr_ptrs = (host_addr_list_t *)
((char *) host_aliases + sizeof (*host_aliases));
hostname = (char *) h_addr_ptrs + sizeof (*h_addr_ptrs);
for (cp = name;; ++cp)
{
if (!*cp)
{
if (*--cp == '.')
break;
/* All-IPv6-legal, no dot at the end. Fake up a
hostent as if we'd actually done a lookup. */
if (inet_pton (af, name, host_addr) <= 0)
{
__set_h_errno (HOST_NOT_FOUND);
#ifndef HAVE_LOOKUP_BUFFER
result = (struct hostent *) NULL;
#endif
goto done;
}
strcpy (hostname, name);
host->h_name = hostname;
host->h_aliases = *host_aliases;
(*host_aliases)[0] = NULL;
(*h_addr_ptrs)[0] = (char *) host_addr;
(*h_addr_ptrs)[1] = (char *) 0;
host->h_addr_list = *h_addr_ptrs;
host->h_addrtype = af;
host->h_length = addr_size;
__set_h_errno (NETDB_SUCCESS);
#ifdef HAVE_LOOKUP_BUFFER
status = NSS_STATUS_SUCCESS;
#else
result = host;
#endif
goto done;
}
if (!isxdigit (*cp) && *cp != ':' && *cp != '.') break;
}
}
}
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