1 /* $NetBSD: getusershell.c,v 1.2 2017/01/28 21:31:50 christos Exp $ */
2
3 /*
4 * Copyright (c) 1985, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <config.h>
33
34 #ifndef HAVE_GETUSERSHELL
35
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <ctype.h>
40 #ifdef HAVE_PATHS_H
41 #include <paths.h>
42 #endif
43 #ifdef HAVE_SYS_TYPES_H
44 #include <sys/types.h>
45 #endif
46 #ifdef HAVE_SYS_STAT_H
47 #include <sys/stat.h>
48 #endif
49 #ifdef HAVE_SYS_PARAM_H
50 #include <sys/param.h>
51 #endif
52
53 #ifdef HAVE_USERSEC_H
54 struct aud_rec;
55 #include <usersec.h>
56 #endif
57 #ifdef HAVE_USERCONF_H
58 #include <userconf.h>
59 #endif
60 #include <krb5/roken.h>
61
62 #ifndef _PATH_SHELLS
63 #define _PATH_SHELLS "/etc/shells"
64 #endif
65
66 #ifndef _PATH_BSHELL
67 #define _PATH_BSHELL "/bin/sh"
68 #endif
69
70 #ifndef _PATH_CSHELL
71 #define _PATH_CSHELL "/bin/csh"
72 #endif
73
74 /*
75 * Local shells should NOT be added here. They should be added in
76 * /etc/shells.
77 */
78
79 static char *okshells[] = { _PATH_BSHELL, _PATH_CSHELL, NULL };
80 static char **curshell, **shells, *strings;
81 static char **initshells (void);
82
83 /*
84 * Get a list of shells from _PATH_SHELLS, if it exists.
85 */
86 ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
getusershell()87 getusershell()
88 {
89 char *ret;
90
91 if (curshell == NULL)
92 curshell = initshells();
93 ret = *curshell;
94 if (ret != NULL)
95 curshell++;
96 return (ret);
97 }
98
99 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
endusershell()100 endusershell()
101 {
102 if (shells != NULL)
103 free(shells);
104 shells = NULL;
105 if (strings != NULL)
106 free(strings);
107 strings = NULL;
108 curshell = NULL;
109 }
110
111 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
setusershell()112 setusershell()
113 {
114 curshell = initshells();
115 }
116
117 static char **
initshells()118 initshells()
119 {
120 char **sp, *cp;
121 #ifdef HAVE_GETCONFATTR
122 char *tmp;
123 int nsh;
124 #else
125 FILE *fp;
126 #endif
127 struct stat statb;
128
129 free(shells);
130 shells = NULL;
131 free(strings);
132 strings = NULL;
133 #ifdef HAVE_GETCONFATTR
134 if(getconfattr(SC_SYS_LOGIN, SC_SHELLS, &tmp, SEC_LIST) != 0)
135 return okshells;
136
137 for(cp = tmp, nsh = 0; *cp; cp += strlen(cp) + 1, nsh++);
138
139 shells = calloc(nsh + 1, sizeof(*shells));
140 if(shells == NULL)
141 return okshells;
142
143 strings = malloc(cp - tmp);
144 if(strings == NULL) {
145 free(shells);
146 shells = NULL;
147 return okshells;
148 }
149 memcpy(strings, tmp, cp - tmp);
150 for(sp = shells, cp = strings; *cp; cp += strlen(cp) + 1, sp++)
151 *sp = cp;
152 #else
153 if ((fp = fopen(_PATH_SHELLS, "r")) == NULL)
154 return (okshells);
155 if (fstat(fileno(fp), &statb) == -1) {
156 fclose(fp);
157 return (okshells);
158 }
159 if ((strings = malloc((u_int)statb.st_size)) == NULL) {
160 fclose(fp);
161 return (okshells);
162 }
163 shells = calloc((unsigned)statb.st_size / 3, sizeof (char *));
164 if (shells == NULL) {
165 fclose(fp);
166 free(strings);
167 strings = NULL;
168 return (okshells);
169 }
170 sp = shells;
171 cp = strings;
172 while (fgets(cp, MaxPathLen + 1, fp) != NULL) {
173 while (*cp != '#' && *cp != '/' && *cp != '\0')
174 cp++;
175 if (*cp == '#' || *cp == '\0')
176 continue;
177 *sp++ = cp;
178 while (!isspace((unsigned char)*cp) && *cp != '#' && *cp != '\0')
179 cp++;
180 *cp++ = '\0';
181 }
182 fclose(fp);
183 #endif
184 *sp = NULL;
185 return (shells);
186 }
187 #endif /* HAVE_GETUSERSHELL */
188