xref: /freebsd/lib/libc/rpc/netname.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2009, Sun Microsystems, Inc.
5  * 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 are met:
9  * - Redistributions of source code must retain the above copyright notice,
10  *   this list of conditions and the following disclaimer.
11  * - Redistributions in binary form must reproduce the above copyright notice,
12  *   this list of conditions and the following disclaimer in the documentation
13  *   and/or other materials provided with the distribution.
14  * - Neither the name of Sun Microsystems, Inc. nor the names of its
15  *   contributors may be used to endorse or promote products derived
16  *   from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #if defined(LIBC_SCCS) && !defined(lint)
32 static char sccsid[] = "@(#)netname.c 1.8 91/03/11 Copyr 1986 Sun Micro";
33 #endif
34 #include <sys/cdefs.h>
35 /*
36  * netname utility routines
37  * convert from unix names to network names and vice-versa
38  * This module is operating system dependent!
39  * What we define here will work with any unix system that has adopted
40  * the sun NIS domain architecture.
41  */
42 
43 #include "namespace.h"
44 #include <sys/param.h>
45 #include <rpc/rpc.h>
46 #include <rpc/rpc_com.h>
47 #ifdef YP
48 #include <rpcsvc/yp_prot.h>
49 #include <rpcsvc/ypclnt.h>
50 #endif
51 #include <ctype.h>
52 #include <limits.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <unistd.h>
57 #include "un-namespace.h"
58 
59 #ifndef MAXHOSTNAMELEN
60 #define MAXHOSTNAMELEN 256
61 #endif
62 
63 #define TYPE_BIT(type)  (sizeof (type) * CHAR_BIT)
64 
65 #define TYPE_SIGNED(type) (((type) -1) < 0)
66 
67 /*
68 ** 302 / 1000 is log10(2.0) rounded up.
69 ** Subtract one for the sign bit if the type is signed;
70 ** add one for integer division truncation;
71 ** add one more for a minus sign if the type is signed.
72 */
73 #define INT_STRLEN_MAXIMUM(type) \
74     ((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + 1 + TYPE_SIGNED(type))
75 
76 static char *OPSYS = "unix";
77 
78 /*
79  * Figure out my fully qualified network name
80  */
81 int
82 getnetname(char name[MAXNETNAMELEN+1])
83 {
84 	uid_t uid;
85 
86 	uid = geteuid();
87 	if (uid == 0) {
88 		return (host2netname(name, (char *) NULL, (char *) NULL));
89 	} else {
90 		return (user2netname(name, uid, (char *) NULL));
91 	}
92 }
93 
94 
95 /*
96  * Convert unix cred to network-name
97  */
98 int
99 user2netname(char netname[MAXNETNAMELEN + 1], const uid_t uid, const char *domain)
100 {
101 	char *dfltdom;
102 
103 	if (domain == NULL) {
104 		if (__rpc_get_default_domain(&dfltdom) != 0) {
105 			return (0);
106 		}
107 		domain = dfltdom;
108 	}
109 	if (strlen(domain) + 1 + INT_STRLEN_MAXIMUM(u_long) + 1 + strlen(OPSYS) > MAXNETNAMELEN) {
110 		return (0);
111 	}
112 	(void) sprintf(netname, "%s.%ld@%s", OPSYS, (u_long)uid, domain);
113 	return (1);
114 }
115 
116 
117 /*
118  * Convert host to network-name
119  */
120 int
121 host2netname(char netname[MAXNETNAMELEN + 1], const char *host, const char *domain)
122 {
123 	char *dfltdom;
124 	char hostname[MAXHOSTNAMELEN+1];
125 
126 	if (domain == NULL) {
127 		if (__rpc_get_default_domain(&dfltdom) != 0) {
128 			return (0);
129 		}
130 		domain = dfltdom;
131 	}
132 	if (host == NULL) {
133 		(void) gethostname(hostname, sizeof(hostname));
134 		host = hostname;
135 	}
136 	if (strlen(domain) + 1 + strlen(host) + 1 + strlen(OPSYS) > MAXNETNAMELEN) {
137 		return (0);
138 	}
139 	(void) sprintf(netname, "%s.%s@%s", OPSYS, host, domain);
140 	return (1);
141 }
142