1 /* Copyright (c) 1997-2022 Free Software Foundation, Inc.
2    This file is part of the GNU C Library.
3 
4    The GNU C Library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Lesser General Public
6    License as published by the Free Software Foundation; either
7    version 2.1 of the License, or (at your option) any later version.
8 
9    The GNU C Library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Lesser General Public License for more details.
13 
14    You should have received a copy of the GNU Lesser General Public
15    License along with the GNU C Library; if not, see
16    <https://www.gnu.org/licenses/>.  */
17 
18 #include <errno.h>
19 #include <string.h>
20 #include <rpcsvc/nis.h>
21 #include <shlib-compat.h>
22 
23 nis_name
nis_leaf_of(const_nis_name name)24 nis_leaf_of (const_nis_name name)
25 {
26   static char result[NIS_MAXNAMELEN + 1];
27 
28   return nis_leaf_of_r (name, result, NIS_MAXNAMELEN);
29 }
libnsl_hidden_nolink_def(nis_leaf_of,GLIBC_2_1)30 libnsl_hidden_nolink_def (nis_leaf_of, GLIBC_2_1)
31 
32 nis_name
33 nis_leaf_of_r (const_nis_name name, char *buffer, size_t buflen)
34 {
35   size_t i = 0;
36 
37   buffer[0] = '\0';
38 
39   while (name[i] != '.' && name[i] != '\0')
40     i++;
41 
42   if (__glibc_unlikely (i >= buflen))
43     {
44       __set_errno (ERANGE);
45       return NULL;
46     }
47 
48   *((char *) __mempcpy (buffer, name, i)) = '\0';
49 
50   return buffer;
51 }
libnsl_hidden_nolink_def(nis_leaf_of_r,GLIBC_2_1)52 libnsl_hidden_nolink_def (nis_leaf_of_r, GLIBC_2_1)
53 
54 nis_name
55 nis_name_of (const_nis_name name)
56 {
57   static char result[NIS_MAXNAMELEN + 1];
58 
59   return nis_name_of_r (name, result, NIS_MAXNAMELEN);
60 }
libnsl_hidden_nolink_def(nis_name_of,GLIBC_2_1)61 libnsl_hidden_nolink_def (nis_name_of, GLIBC_2_1)
62 
63 nis_name
64 nis_name_of_r (const_nis_name name, char *buffer, size_t buflen)
65 {
66   char *local_domain;
67   int diff;
68 
69   local_domain = nis_local_directory ();
70 
71   diff = strlen (name) - strlen (local_domain);
72   if (diff <= 0)
73     return NULL;
74 
75   if (strcmp (&name[diff], local_domain) != 0)
76     return NULL;
77 
78   if ((size_t) diff >= buflen)
79     {
80       __set_errno (ERANGE);
81       return NULL;
82     }
83 
84   *((char *) __mempcpy (buffer, name, diff - 1)) = '\0';
85 
86   if (diff - 1 == 0)
87     return NULL;
88 
89   return buffer;
90 }
libnsl_hidden_nolink_def(nis_name_of_r,GLIBC_2_1)91 libnsl_hidden_nolink_def (nis_name_of_r, GLIBC_2_1)
92 
93 static __always_inline int
94 count_dots (const_nis_name str)
95 {
96   int count = 0;
97 
98   for (size_t i = 0; str[i] != '\0'; ++i)
99     if (str[i] == '.')
100       ++count;
101 
102   return count;
103 }
104 
105 nis_name *
nis_getnames(const_nis_name name)106 nis_getnames (const_nis_name name)
107 {
108   const char *local_domain = nis_local_directory ();
109   size_t local_domain_len = strlen (local_domain);
110   size_t name_len = strlen (name);
111   char *path;
112   int pos = 0;
113   char *saveptr = NULL;
114   int have_point;
115   const char *cp;
116   const char *cp2;
117 
118   int count = 2;
119   nis_name *getnames = malloc ((count + 1) * sizeof (char *));
120   if (__glibc_unlikely (getnames == NULL))
121       return NULL;
122 
123   /* Do we have a fully qualified NIS+ name ? If yes, give it back */
124   if (name[name_len - 1] == '.')
125     {
126       if ((getnames[0] = strdup (name)) == NULL)
127 	{
128 	free_null:
129 	  while (pos-- > 0)
130 	    free (getnames[pos]);
131 	  free (getnames);
132 	  return NULL;
133 	}
134 
135       getnames[1] = NULL;
136 
137       return getnames;
138     }
139 
140   /* If the passed NAME is shared a suffix (the latter of course with
141      a final dot) with each other we pass back NAME with a final
142      dot.  */
143   if (local_domain_len > 2)
144     {
145       have_point = 0;
146       cp = &local_domain[local_domain_len - 2];
147       cp2 = &name[name_len - 1];
148 
149       while (*cp == *cp2)
150 	{
151 	  if (*cp == '.')
152 	    have_point = 1;
153 	  --cp;
154 	  --cp2;
155 	  if (cp < local_domain)
156 	    {
157 	      have_point = cp2 < name || *cp2 == '.';
158 	      break;
159 	    }
160 	  if (cp2 < name)
161 	    {
162 	      have_point = *cp == '.';
163 	      break;
164 	    }
165 	}
166 
167       if (have_point)
168 	{
169 	  getnames[0] = malloc (name_len + 2);
170 	  if (getnames[0] == NULL)
171 	    goto free_null;
172 
173 	  strcpy (stpcpy (getnames[0], name), ".");
174 	  ++pos;
175 	}
176     }
177 
178   /* Get the search path, where we have to search "name" */
179   path = getenv ("NIS_PATH");
180   if (path == NULL)
181     path = strdupa ("$");
182   else
183     path = strdupa (path);
184 
185   have_point = strchr (name, '.') != NULL;
186 
187   cp = __strtok_r (path, ":", &saveptr);
188   while (cp)
189     {
190       if (strcmp (cp, "$") == 0)
191 	{
192 	  const char *cptr = local_domain;
193 	  char *tmp;
194 
195 	  while (*cptr != '\0' && count_dots (cptr) >= 2)
196 	    {
197 	      if (pos >= count)
198 		{
199 		  count += 5;
200 		  nis_name *newp = realloc (getnames,
201 					    (count + 1) * sizeof (char *));
202 		  if (__glibc_unlikely (newp == NULL))
203 		    goto free_null;
204 		  getnames = newp;
205 		}
206 	      tmp = malloc (strlen (cptr) + local_domain_len + name_len + 2);
207 	      if (__glibc_unlikely (tmp == NULL))
208 		goto free_null;
209 
210 	      getnames[pos] = tmp;
211 	      tmp = stpcpy (tmp, name);
212 	      *tmp++ = '.';
213 	      if (cptr[1] != '\0')
214 		stpcpy (tmp, cptr);
215 	      else
216 		++cptr;
217 
218 	      ++pos;
219 
220 	      while (*cptr != '.' && *cptr != '\0')
221 		++cptr;
222 	      if (cptr[0] != '\0' && cptr[1] != '\0')
223 		/* If we have only ".", don't remove the "." */
224 		++cptr;
225 	    }
226 	}
227       else
228 	{
229 	  char *tmp;
230 	  size_t cplen = strlen (cp);
231 
232 	  if (cp[cplen - 1] == '$')
233 	    {
234 	      char *p;
235 
236 	      tmp = malloc (cplen + local_domain_len + name_len + 2);
237 	      if (__glibc_unlikely (tmp == NULL))
238 		goto free_null;
239 
240 	      p = __stpcpy (tmp, name);
241 	      *p++ = '.';
242 	      p = __mempcpy (p, cp, cplen);
243 	      --p;
244 	      if (p[-1] != '.')
245 		*p++ = '.';
246 	      __stpcpy (p, local_domain);
247 	    }
248 	  else
249 	    {
250 	      char *p;
251 
252 	      tmp = malloc (cplen + name_len + 3);
253 	      if (__glibc_unlikely (tmp == NULL))
254 		goto free_null;
255 
256 	      p = __mempcpy (tmp, name, name_len);
257 	      *p++ = '.';
258 	      p = __mempcpy (p, cp, cplen);
259 	      if (p[-1] != '.')
260 		*p++ = '.';
261 	      *p = '\0';
262 	    }
263 
264 	  if (pos >= count)
265 	    {
266 	      count += 5;
267 	      nis_name *newp = realloc (getnames,
268 					(count + 1) * sizeof (char *));
269 	      if (__glibc_unlikely (newp == NULL))
270 		{
271 		  free (tmp);
272 		  goto free_null;
273 		}
274 	      getnames = newp;
275 	    }
276 	  getnames[pos] = tmp;
277 	  ++pos;
278 	}
279       cp = __strtok_r (NULL, ":", &saveptr);
280     }
281 
282   if (pos == 0
283       && __asprintf (&getnames[pos++], "%s%s%s%s",
284 		     name, name[name_len - 1] == '.' ? "" : ".",
285 		     local_domain,
286 		     local_domain[local_domain_len - 1] == '.' ? "" : ".") < 0)
287     goto free_null;
288 
289   getnames[pos] = NULL;
290 
291   return getnames;
292 }
libnsl_hidden_nolink_def(nis_getnames,GLIBC_2_1)293 libnsl_hidden_nolink_def (nis_getnames, GLIBC_2_1)
294 
295 void
296 nis_freenames (nis_name *names)
297 {
298   int i = 0;
299 
300   while (names[i] != NULL)
301     {
302       free (names[i]);
303       ++i;
304     }
305 
306   free (names);
307 }
libnsl_hidden_nolink_def(nis_freenames,GLIBC_2_1)308 libnsl_hidden_nolink_def  (nis_freenames, GLIBC_2_1)
309 
310 name_pos
311 nis_dir_cmp (const_nis_name n1, const_nis_name n2)
312 {
313   int len1, len2;
314 
315   len1 = strlen (n1);
316   len2 = strlen (n2);
317 
318   if (len1 == len2)
319     {
320       if (strcmp (n1, n2) == 0)
321 	return SAME_NAME;
322       else
323 	return NOT_SEQUENTIAL;
324     }
325 
326   if (len1 < len2)
327     {
328       if (n2[len2 - len1 - 1] != '.')
329 	return NOT_SEQUENTIAL;
330       else if (strcmp (&n2[len2 - len1], n1) == 0)
331 	return HIGHER_NAME;
332       else
333 	return NOT_SEQUENTIAL;
334     }
335   else
336     {
337       if (n1[len1 - len2 - 1] != '.')
338 	return NOT_SEQUENTIAL;
339       else if (strcmp (&n1[len1 - len2], n2) == 0)
340 	return LOWER_NAME;
341       else
342 	return NOT_SEQUENTIAL;
343 
344     }
345 }
libnsl_hidden_nolink_def(nis_dir_cmp,GLIBC_2_1)346 libnsl_hidden_nolink_def (nis_dir_cmp, GLIBC_2_1)
347 
348 void
349 nis_destroy_object (nis_object *obj)
350 {
351   nis_free_object (obj);
352 }
353 libnsl_hidden_nolink_def (nis_destroy_object, GLIBC_2_1)
354