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 <unistd.h>
21#include <libintl.h>
22#include <rpcsvc/nis.h>
23#include <shlib-compat.h>
24
25nis_name
26nis_local_group (void)
27{
28 static char __nisgroup[NIS_MAXNAMELEN + 1];
29
30 char *cptr;
31 if (__nisgroup[0] == '\0'
32 && (cptr = getenv (name: "NIS_GROUP")) != NULL
33 && cptr[0] != '\0'
34 && strlen (s: cptr) < NIS_MAXNAMELEN)
35 {
36 char *cp = stpcpy (__nisgroup, cptr);
37
38 if (cp[-1] != '.')
39 {
40 cptr = nis_local_directory ();
41 if ((cp - __nisgroup) + strlen (s: cptr) + 1 < NIS_MAXNAMELEN)
42 {
43 *cp++ = '.';
44 strcpy (dest: cp, src: cptr);
45 }
46 else
47 __nisgroup[0] = '\0';
48 }
49 }
50
51 return __nisgroup;
52}
53libnsl_hidden_nolink_def (nis_local_group, GLIBC_2_1)
54
55nis_name
56nis_local_directory (void)
57{
58 static char __nisdomainname[NIS_MAXNAMELEN + 1];
59
60 if (__nisdomainname[0] == '\0')
61 {
62 if (getdomainname (name: __nisdomainname, NIS_MAXNAMELEN) < 0)
63 __nisdomainname[0] = '\0';
64 else
65 {
66 char *cp = rawmemchr (s: __nisdomainname, c: '\0');
67
68 /* Missing trailing dot? */
69 if (cp[-1] != '.')
70 {
71 *cp++ = '.';
72 *cp = '\0';
73 }
74 }
75 }
76
77 return __nisdomainname;
78}
79libnsl_hidden_nolink_def (nis_local_directory, GLIBC_2_1)
80
81nis_name
82nis_local_principal (void)
83{
84 static char __principal[NIS_MAXNAMELEN + 1];
85
86 if (__principal[0] == '\0')
87 {
88 char buf[NIS_MAXNAMELEN + 1];
89 nis_result *res;
90 uid_t uid = geteuid ();
91
92 if (uid != 0)
93 {
94 int len = snprintf (s: buf, NIS_MAXNAMELEN - 1,
95 format: "[auth_name=%d,auth_type=LOCAL],cred.org_dir.%s",
96 uid, nis_local_directory ());
97
98 if (len >= NIS_MAXNAMELEN - 1)
99 nobody:
100 /* XXX The buffer is too small. Can this happen??? */
101 return strcpy (dest: __principal, src: "nobody");
102
103 if (buf[len - 1] != '.')
104 {
105 buf[len++] = '.';
106 buf[len] = '\0';
107 }
108
109 res = nis_list (buf, USE_DGRAM + NO_AUTHINFO + FOLLOW_LINKS
110 + FOLLOW_PATH, NULL, NULL);
111
112 if (res == NULL)
113 goto nobody;
114
115 if (NIS_RES_STATUS (res) == NIS_SUCCESS)
116 {
117 if (res->objects.objects_len > 1)
118 {
119 /* More than one principal with same uid? something
120 wrong with cred table. Should be unique. Warn user
121 and continue. */
122 printf (_("\
123LOCAL entry for UID %d in directory %s not unique\n"),
124 uid, nis_local_directory ());
125 }
126 strcpy (dest: __principal, ENTRY_VAL (res->objects.objects_val, 0));
127 nis_freeresult (res);
128 return __principal;
129 }
130 else
131 {
132 nis_freeresult (res);
133 goto nobody;
134 }
135 }
136 else
137 return strcpy (dest: __principal, src: nis_local_host ());
138
139 /* Should be never reached */
140 goto nobody;
141 }
142 return __principal;
143}
144libnsl_hidden_nolink_def (nis_local_principal, GLIBC_2_1)
145
146nis_name
147nis_local_host (void)
148{
149 static char __nishostname[NIS_MAXNAMELEN + 1];
150
151 if (__nishostname[0] == '\0')
152 {
153 if (gethostname (name: __nishostname, NIS_MAXNAMELEN) < 0)
154 __nishostname[0] = '\0';
155 else
156 {
157 char *cp = rawmemchr (s: __nishostname, c: '\0');
158 int len = cp - __nishostname;
159
160 /* Hostname already fully qualified? */
161 if (cp[-1] == '.')
162 return __nishostname;
163
164 if (len + strlen (s: nis_local_directory ()) + 1 > NIS_MAXNAMELEN)
165 {
166 __nishostname[0] = '\0';
167 return __nishostname;
168 }
169
170 *cp++ = '.';
171 strncpy (dest: cp, src: nis_local_directory (), NIS_MAXNAMELEN - len -1);
172 __nishostname[NIS_MAXNAMELEN] = '\0';
173 }
174 }
175
176 return __nishostname;
177}
178libnsl_hidden_nolink_def (nis_local_host, GLIBC_2_1)
179

source code of glibc/nis/nis_local_names.c