xref: /freebsd/lib/libc/rpc/netname.c (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
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 /*
35  * netname utility routines
36  * convert from unix names to network names and vice-versa
37  * This module is operating system dependent!
38  * What we define here will work with any unix system that has adopted
39  * the sun NIS domain architecture.
40  */
41 
42 #include "namespace.h"
43 #include <sys/param.h>
44 #include <rpc/rpc.h>
45 #include <rpc/rpc_com.h>
46 #ifdef YP
47 #include <rpcsvc/yp_prot.h>
48 #include <rpcsvc/ypclnt.h>
49 #endif
50 #include <ctype.h>
51 #include <limits.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 #include "un-namespace.h"
57 
58 #ifndef MAXHOSTNAMELEN
59 #define MAXHOSTNAMELEN 256
60 #endif
61 
62 #define TYPE_BIT(type)  (sizeof (type) * CHAR_BIT)
63 
64 #define TYPE_SIGNED(type) (((type) -1) < 0)
65 
66 /*
67 ** 302 / 1000 is log10(2.0) rounded up.
68 ** Subtract one for the sign bit if the type is signed;
69 ** add one for integer division truncation;
70 ** add one more for a minus sign if the type is signed.
71 */
72 #define INT_STRLEN_MAXIMUM(type) \
73     ((TYPE_BIT(type) - TYPE_SIGNED(type)) * 302 / 1000 + 1 + TYPE_SIGNED(type))
74 
75 static char *OPSYS = "unix";
76 
77 /*
78  * Figure out my fully qualified network name
79  */
80 int
81 getnetname(char name[MAXNETNAMELEN+1])
82 {
83 	uid_t uid;
84 
85 	uid = geteuid();
86 	if (uid == 0) {
87 		return (host2netname(name, (char *) NULL, (char *) NULL));
88 	} else {
89 		return (user2netname(name, uid, (char *) NULL));
90 	}
91 }
92 
93 
94 /*
95  * Convert unix cred to network-name
96  */
97 int
98 user2netname(char netname[MAXNETNAMELEN + 1], const uid_t uid, const char *domain)
99 {
100 	char *dfltdom;
101 
102 	if (domain == NULL) {
103 		if (__rpc_get_default_domain(&dfltdom) != 0) {
104 			return (0);
105 		}
106 		domain = dfltdom;
107 	}
108 	if (strlen(domain) + 1 + INT_STRLEN_MAXIMUM(u_long) + 1 + strlen(OPSYS) > MAXNETNAMELEN) {
109 		return (0);
110 	}
111 	(void) sprintf(netname, "%s.%ld@%s", OPSYS, (u_long)uid, domain);
112 	return (1);
113 }
114 
115 
116 /*
117  * Convert host to network-name
118  */
119 int
120 host2netname(char netname[MAXNETNAMELEN + 1], const char *host, const char *domain)
121 {
122 	char *dfltdom;
123 	char hostname[MAXHOSTNAMELEN+1];
124 
125 	if (domain == NULL) {
126 		if (__rpc_get_default_domain(&dfltdom) != 0) {
127 			return (0);
128 		}
129 		domain = dfltdom;
130 	}
131 	if (host == NULL) {
132 		(void) gethostname(hostname, sizeof(hostname));
133 		host = hostname;
134 	}
135 	if (strlen(domain) + 1 + strlen(host) + 1 + strlen(OPSYS) > MAXNETNAMELEN) {
136 		return (0);
137 	}
138 	(void) sprintf(netname, "%s.%s@%s", OPSYS, host, domain);
139 	return (1);
140 }
141