enum nss_status
_nss_dns_getnetbyname_r (const char *name, struct netent *result,
char *buffer, size_t buflen, int *errnop,
int *herrnop)
{
/* Return entry for network with NAME. */
union
{
querybuf *buf;
u_char *ptr;
} net_buffer;
querybuf *orig_net_buffer;
int anslen;
char *qbuf;
enum nss_status status;
if (__res_maybe_init (&_res, 0) == -1)
return NSS_STATUS_UNAVAIL;
qbuf = strdupa (name);
net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
anslen = __libc_res_nsearch (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
1024, &net_buffer.ptr, NULL, NULL, NULL, NULL);
if (anslen < 0)
{
/* Nothing found. */
*errnop = errno;
if (net_buffer.buf != orig_net_buffer)
free (net_buffer.buf);
return (errno == ECONNREFUSED
|| errno == EPFNOSUPPORT
|| errno == EAFNOSUPPORT)
? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
}
status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen,
errnop, herrnop, BYNAME);
if (net_buffer.buf != orig_net_buffer)
free (net_buffer.buf);
return status;
}
enum nss_status
_nss_dns_getnetbyaddr_r (uint32_t net, int type, struct netent *result,
char *buffer, size_t buflen, int *errnop,
int *herrnop)
{
/* Return entry for network with NAME. */
enum nss_status status;
union
{
querybuf *buf;
u_char *ptr;
} net_buffer;
querybuf *orig_net_buffer;
unsigned int net_bytes[4];
char qbuf[MAXDNAME];
int cnt, anslen;
u_int32_t net2;
int olderr = errno;
/* No net address lookup for IPv6 yet. */
if (type != AF_INET)
return NSS_STATUS_UNAVAIL;
if (__res_maybe_init (&_res, 0) == -1)
return NSS_STATUS_UNAVAIL;
net2 = (u_int32_t) net;
for (cnt = 4; net2 != 0; net2 >>= 8)
net_bytes[--cnt] = net2 & 0xff;
switch (cnt)
{
case 3:
/* Class A network. */
sprintf (qbuf, "0.0.0.%u.in-addr.arpa", net_bytes[3]);
break;
case 2:
/* Class B network. */
sprintf (qbuf, "0.0.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2]);
break;
case 1:
/* Class C network. */
sprintf (qbuf, "0.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
net_bytes[1]);
break;
case 0:
/* Class D - E network. */
sprintf (qbuf, "%u.%u.%u.%u.in-addr.arpa", net_bytes[3], net_bytes[2],
net_bytes[1], net_bytes[0]);
break;
}
net_buffer.buf = orig_net_buffer = (querybuf *) alloca (1024);
anslen = __libc_res_nquery (&_res, qbuf, C_IN, T_PTR, net_buffer.buf->buf,
1024, &net_buffer.ptr, NULL, NULL, NULL, NULL);
if (anslen < 0)
{
/* Nothing found. */
int err = errno;
__set_errno (olderr);
if (net_buffer.buf != orig_net_buffer)
free (net_buffer.buf);
return (err == ECONNREFUSED
|| err == EPFNOSUPPORT
|| err == EAFNOSUPPORT)
? NSS_STATUS_UNAVAIL : NSS_STATUS_NOTFOUND;
}
status = getanswer_r (net_buffer.buf, anslen, result, buffer, buflen,
errnop, herrnop, BYADDR);
if (net_buffer.buf != orig_net_buffer)
free (net_buffer.buf);
if (status == NSS_STATUS_SUCCESS)
{
/* Strip trailing zeros. */
unsigned int u_net = net; /* Maybe net should be unsigned? */
while ((u_net & 0xff) == 0 && u_net != 0)
u_net >>= 8;
result->n_net = u_net;
}
int
__nss_hostname_digits_dots (const char *name, struct hostent *resbuf,
char **buffer, size_t *buffer_size,
size_t buflen, struct hostent **result,
enum nss_status *status, int af, int *h_errnop)
{
int save;
/* We have to test for the use of IPv6 which can only be done by
examining `_res'. */
if (__res_maybe_init (&_res, 0) == -1)
{
if (h_errnop)
*h_errnop = NETDB_INTERNAL;
if (buffer_size == NULL)
*status = NSS_STATUS_TRYAGAIN;
else
*result = NULL;
return -1;
}
/*
* 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;
typedef unsigned char host_addr_t[16];
host_addr_t *host_addr;
typedef char *host_addr_list_t[2];
host_addr_list_t *h_addr_ptrs;
char **h_alias_ptr;
size_t size_needed;
int addr_size;
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_addr)
+ sizeof (*h_addr_ptrs)
+ sizeof (*h_alias_ptr) + strlen (name) + 1);
if (buffer_size == NULL)
{
if (buflen < size_needed)
{
*status = NSS_STATUS_TRYAGAIN;
if (h_errnop != NULL)
*h_errnop = NETDB_INTERNAL;
__set_errno (ERANGE);
goto done;
}
}
else if (buffer_size != NULL && *buffer_size < size_needed)
{
char *new_buf;
*buffer_size = size_needed;
new_buf = (char *) realloc (*buffer, *buffer_size);
if (new_buf == NULL)
{
save = errno;
free (*buffer);
*buffer = NULL;
*buffer_size = 0;
__set_errno (save);
if (h_errnop != NULL)
*h_errnop = NETDB_INTERNAL;
*result = NULL;
goto done;
}
*buffer = new_buf;
}
memset (*buffer, '\0', size_needed);
host_addr = (host_addr_t *) *buffer;
h_addr_ptrs = (host_addr_list_t *)
((char *) host_addr + sizeof (*host_addr));
h_alias_ptr = (char **) ((char *) h_addr_ptrs + sizeof (*h_addr_ptrs));
hostname = (char *) h_alias_ptr + sizeof (*h_alias_ptr);
if (isdigit (name[0]))
{
for (cp = name;; ++cp)
{
if (*cp == '\0')
{
int ok;
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 (af == AF_INET)
ok = __inet_aton (name, (struct in_addr *) host_addr);
else
{
assert (af == AF_INET6);
ok = inet_pton (af, name, host_addr) > 0;
}
if (! ok)
{
*h_errnop = HOST_NOT_FOUND;
if (buffer_size == NULL)
*status = NSS_STATUS_NOTFOUND;
else
*result = NULL;
goto done;
}
resbuf->h_name = strcpy (hostname, name);
h_alias_ptr[0] = NULL;
resbuf->h_aliases = h_alias_ptr;
(*h_addr_ptrs)[0] = (char *) host_addr;
(*h_addr_ptrs)[1] = NULL;
resbuf->h_addr_list = *h_addr_ptrs;
if (af == AF_INET && (_res.options & RES_USE_INET6))
{
/* We need to change the IP v4 address into the
IP v6 address. */
char tmp[INADDRSZ];
char *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);
resbuf->h_addrtype = AF_INET6;
resbuf->h_length = IN6ADDRSZ;
}
else
{
resbuf->h_addrtype = af;
resbuf->h_length = addr_size;
}
if (h_errnop != NULL)
*h_errnop = NETDB_SUCCESS;
if (buffer_size == NULL)
*status = NSS_STATUS_SUCCESS;
else
*result = resbuf;
goto done;
}
if (!isdigit (*cp) && *cp != '.')
break;
}
}
if ((isxdigit (name[0]) && strchr (name, ':') != NULL) || name[0] == ':')
{
switch (af)
{
default:
af = (_res.options & RES_USE_INET6) ? AF_INET6 : AF_INET;
if (af == AF_INET6)
{
addr_size = IN6ADDRSZ;
break;
}
/* FALLTHROUGH */
case AF_INET:
/* This is not possible. We cannot represent an IPv6 address
in an `struct in_addr' variable. */
*h_errnop = HOST_NOT_FOUND;
if (buffer_size == NULL)
*status = NSS_STATUS_NOTFOUND;
else
*result = NULL;
goto done;
case AF_INET6:
addr_size = IN6ADDRSZ;
break;
}
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_INET6, name, host_addr) <= 0)
{
*h_errnop = HOST_NOT_FOUND;
if (buffer_size == NULL)
*status = NSS_STATUS_NOTFOUND;
else
*result = NULL;
goto done;
}
resbuf->h_name = strcpy (hostname, name);
h_alias_ptr[0] = NULL;
resbuf->h_aliases = h_alias_ptr;
(*h_addr_ptrs)[0] = (char *) host_addr;
(*h_addr_ptrs)[1] = (char *) 0;
resbuf->h_addr_list = *h_addr_ptrs;
resbuf->h_addrtype = AF_INET6;
resbuf->h_length = addr_size;
*h_errnop = NETDB_SUCCESS;
if (buffer_size == NULL)
*status = NSS_STATUS_SUCCESS;
else
*result = resbuf;
goto done;
}
if (!isxdigit (*cp) && *cp != ':' && *cp != '.')
break;
}
}
}
return 0;
done:
return 1;
}
