xref: /dragonfly/lib/libutil/login_auth.c (revision 1de703da)
1 /*-
2  * Copyright (c) 1996 by
3  * Sean Eric Fagan <sef@kithrup.com>
4  * David Nugent <davidn@blaze.net.au>
5  * All rights reserved.
6  *
7  * Portions copyright (c) 1995,1997 by
8  * Berkeley Software Design, Inc.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, is permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice immediately at the beginning of the file, without modification,
16  *    this list of conditions, and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. This work was done expressly for inclusion into FreeBSD.  Other use
21  *    is permitted provided this notation is included.
22  * 4. Absolutely no warranty of function or purpose is made by the authors.
23  * 5. Modifications may be freely made to this file providing the above
24  *    conditions are met.
25  *
26  * Low-level routines relating to the user capabilities database
27  *
28  * $FreeBSD: src/lib/libutil/login_auth.c,v 1.11 1999/08/28 00:05:45 peter Exp $
29  * $DragonFly: src/lib/libutil/login_auth.c,v 1.2 2003/06/17 04:26:51 dillon Exp $
30  */
31 
32 #include <sys/types.h>
33 #include <sys/time.h>
34 #include <sys/resource.h>
35 #include <sys/stat.h>
36 #include <sys/param.h>
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <limits.h>
40 #include <stdio.h>
41 #include <ctype.h>
42 #include <pwd.h>
43 #include <stdlib.h>
44 #include <string.h>
45 #include <syslog.h>
46 #include <unistd.h>
47 #include <login_cap.h>
48 #include <stdarg.h>
49 #include <paths.h>
50 #include <sys/socket.h>
51 #include <sys/wait.h>
52 #include <err.h>
53 #include <libutil.h>
54 
55 
56 /*
57  * auth_checknologin()
58  * Checks for the existance of a nologin file in the login_cap
59  * capability <lc>.  If there isn't one specified, then it checks
60  * to see if this class should just ignore nologin files.  Lastly,
61  * it tries to print out the default nologin file, and, if such
62  * exists, it exits.
63  */
64 
65 void
66 auth_checknologin(login_cap_t *lc)
67 {
68   char *file;
69 
70   /* Do we ignore a nologin file? */
71   if (login_getcapbool(lc, "ignorenologin", 0))
72     return;
73 
74   /* Note that <file> will be "" if there is no nologin capability */
75   if ((file = login_getcapstr(lc, "nologin", "", NULL)) == NULL)
76     exit(1);
77 
78   /*
79    * *file is true IFF there was a "nologin" capability
80    * Note that auth_cat() returns 1 only if the specified
81    * file exists, and is readable.  E.g., /.nologin exists.
82    */
83   if ((*file && auth_cat(file)) || auth_cat(_PATH_NOLOGIN))
84     exit(1);
85 }
86 
87 
88 /*
89  * auth_cat()
90  * Checks for the readability of <file>; if it can be opened for
91  * reading, it prints it out to stdout, and then exits.  Otherwise,
92  * it returns 0 (meaning no nologin file).
93  */
94 
95 int
96 auth_cat(const char *file)
97 {
98   int fd, count;
99   char buf[BUFSIZ];
100 
101   if ((fd = open(file, O_RDONLY)) < 0)
102     return 0;
103   while ((count = read(fd, buf, sizeof(buf))) > 0)
104     (void)write(fileno(stdout), buf, count);
105   close(fd);
106   sleep(5);	/* wait an arbitrary time to drain */
107   return 1;
108 }
109