1 /* Copyright (C) 2015-2022 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 <nss.h>
19 #include <string.h>
20 
21 /* Rewrite VALUE to a valid field value in the NSS database.  Invalid
22    characters are replaced with a single space character ' '.  If
23    VALUE is NULL, the empty string is returned.  *TO_BE_FREED is
24    overwritten with a pointer the caller has to free if the function
25    returns successfully.  On failure, return NULL.  */
26 const char *
__nss_rewrite_field(const char * value,char ** to_be_freed)27 __nss_rewrite_field (const char *value, char **to_be_freed)
28 {
29   *to_be_freed = NULL;
30   if (value == NULL)
31     return "";
32 
33   /* Search for non-allowed characters.  */
34   const char *p = strpbrk (value, __nss_invalid_field_characters);
35   if (p == NULL)
36     return value;
37   *to_be_freed = __strdup (value);
38   if (*to_be_freed == NULL)
39     return NULL;
40 
41   /* Switch pointer to freshly-allocated buffer.  */
42   char *bad = *to_be_freed + (p - value);
43   do
44     {
45       *bad = ' ';
46       bad = strpbrk (bad + 1, __nss_invalid_field_characters);
47     }
48   while (bad != NULL);
49 
50   return *to_be_freed;
51 }
52