1 /* Copyright (C) 1997-2020 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by H.J. Lu <hjl@gnu.ai.mit.edu>, 1997.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
25 #include <resolv/resolv-internal.h>
26 #include <resolv/resolv_context.h>
28 #include <arpa/inet.h>
32 # include <nscd/nscd_proto.h>
36 __nss_hostname_digits_dots (const char *name, struct hostent *resbuf,
37 char **buffer, size_t *buffer_size,
38 size_t buflen, struct hostent **result,
39 enum nss_status *status, int af, int *h_errnop)
41 /* We have to test for the use of IPv6 which can only be done by
43 struct resolv_context *ctx = __resolv_context_get ();
47 *h_errnop = NETDB_INTERNAL;
48 if (buffer_size == NULL)
49 *status = NSS_STATUS_TRYAGAIN;
54 int ret = __nss_hostname_digits_dots_context
55 (ctx, name, resbuf, buffer, buffer_size, buflen,
56 result, status, af, h_errnop);
57 __resolv_context_put (ctx);
62 __nss_hostname_digits_dots_context (struct resolv_context *ctx,
63 const char *name, struct hostent *resbuf,
64 char **buffer, size_t *buffer_size,
65 size_t buflen, struct hostent **result,
66 enum nss_status *status, int af, int *h_errnop)
71 * disallow names consisting only of digits/dots, unless
74 if (isdigit (name[0]) || isxdigit (name[0]) || name[0] == ':')
78 typedef unsigned char host_addr_t[16];
79 host_addr_t *host_addr;
80 typedef char *host_addr_list_t[2];
81 host_addr_list_t *h_addr_ptrs;
93 addr_size = IN6ADDRSZ;
97 af = res_use_inet6 () ? AF_INET6 : AF_INET;
98 addr_size = af == AF_INET6 ? IN6ADDRSZ : INADDRSZ;
102 size_needed = (sizeof (*host_addr)
103 + sizeof (*h_addr_ptrs)
104 + sizeof (*h_alias_ptr) + strlen (name) + 1);
106 if (buffer_size == NULL)
108 if (buflen < size_needed)
110 *status = NSS_STATUS_TRYAGAIN;
111 if (h_errnop != NULL)
112 *h_errnop = NETDB_INTERNAL;
113 __set_errno (ERANGE);
117 else if (buffer_size != NULL && *buffer_size < size_needed)
120 *buffer_size = size_needed;
121 new_buf = (char *) realloc (*buffer, *buffer_size);
130 if (h_errnop != NULL)
131 *h_errnop = NETDB_INTERNAL;
138 memset (*buffer, '\0', size_needed);
140 host_addr = (host_addr_t *) *buffer;
141 h_addr_ptrs = (host_addr_list_t *)
142 ((char *) host_addr + sizeof (*host_addr));
143 h_alias_ptr = (char **) ((char *) h_addr_ptrs + sizeof (*h_addr_ptrs));
144 hostname = (char *) h_alias_ptr + sizeof (*h_alias_ptr);
146 if (isdigit (name[0]))
148 for (cp = name;; ++cp)
157 /* All-numeric, no dot at the end. Fake up a hostent as if
158 we'd actually done a lookup. What if someone types
159 255.255.255.255? The test below will succeed
162 ok = __inet_aton_exact (name, (struct in_addr *) host_addr);
165 assert (af == AF_INET6);
166 ok = inet_pton (af, name, host_addr) > 0;
170 *h_errnop = HOST_NOT_FOUND;
171 if (buffer_size == NULL)
172 *status = NSS_STATUS_NOTFOUND;
178 resbuf->h_name = strcpy (hostname, name);
179 h_alias_ptr[0] = NULL;
180 resbuf->h_aliases = h_alias_ptr;
181 (*h_addr_ptrs)[0] = (char *) host_addr;
182 (*h_addr_ptrs)[1] = NULL;
183 resbuf->h_addr_list = *h_addr_ptrs;
184 if (af == AF_INET && res_use_inet6 ())
186 /* We need to change the IP v4 address into the
189 char *p = (char *) host_addr;
192 /* Save a copy of the IP v4 address. */
193 memcpy (tmp, host_addr, INADDRSZ);
194 /* Mark this ipv6 addr as a mapped ipv4. */
195 for (i = 0; i < 10; i++)
199 /* Copy the IP v4 address. */
200 memcpy (p, tmp, INADDRSZ);
201 resbuf->h_addrtype = AF_INET6;
202 resbuf->h_length = IN6ADDRSZ;
206 resbuf->h_addrtype = af;
207 resbuf->h_length = addr_size;
209 if (h_errnop != NULL)
210 *h_errnop = NETDB_SUCCESS;
211 if (buffer_size == NULL)
212 *status = NSS_STATUS_SUCCESS;
218 if (!isdigit (*cp) && *cp != '.')
223 if ((isxdigit (name[0]) && strchr (name, ':') != NULL) || name[0] == ':')
228 af = res_use_inet6 () ? AF_INET6 : AF_INET;
231 addr_size = IN6ADDRSZ;
237 /* This is not possible. We cannot represent an IPv6 address
238 in an `struct in_addr' variable. */
239 *h_errnop = HOST_NOT_FOUND;
240 if (buffer_size == NULL)
241 *status = NSS_STATUS_NOTFOUND;
247 addr_size = IN6ADDRSZ;
251 for (cp = name;; ++cp)
258 /* All-IPv6-legal, no dot at the end. Fake up a
259 hostent as if we'd actually done a lookup. */
260 if (inet_pton (AF_INET6, name, host_addr) <= 0)
262 *h_errnop = HOST_NOT_FOUND;
263 if (buffer_size == NULL)
264 *status = NSS_STATUS_NOTFOUND;
270 resbuf->h_name = strcpy (hostname, name);
271 h_alias_ptr[0] = NULL;
272 resbuf->h_aliases = h_alias_ptr;
273 (*h_addr_ptrs)[0] = (char *) host_addr;
274 (*h_addr_ptrs)[1] = (char *) 0;
275 resbuf->h_addr_list = *h_addr_ptrs;
276 resbuf->h_addrtype = AF_INET6;
277 resbuf->h_length = addr_size;
278 *h_errnop = NETDB_SUCCESS;
279 if (buffer_size == NULL)
280 *status = NSS_STATUS_SUCCESS;
286 if (!isxdigit (*cp) && *cp != ':' && *cp != '.')
297 libc_hidden_def (__nss_hostname_digits_dots)