xref: /freebsd/sys/rpc/authunix_prot.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*	$NetBSD: authunix_prot.c,v 1.12 2000/01/22 22:19:17 mycroft Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (c) 2009, Sun Microsystems, Inc.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  * - Redistributions of source code must retain the above copyright notice,
12  *   this list of conditions and the following disclaimer.
13  * - Redistributions in binary form must reproduce the above copyright notice,
14  *   this list of conditions and the following disclaimer in the documentation
15  *   and/or other materials provided with the distribution.
16  * - Neither the name of Sun Microsystems, Inc. nor the names of its
17  *   contributors may be used to endorse or promote products derived
18  *   from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 /*
35  * authunix_prot.c
36  * XDR for UNIX style authentication parameters for RPC
37  *
38  * Copyright (C) 1984, Sun Microsystems, Inc.
39  */
40 
41 #include <sys/param.h>
42 #include <sys/jail.h>
43 #include <sys/kernel.h>
44 #include <sys/systm.h>
45 #include <sys/ucred.h>
46 
47 #include <rpc/types.h>
48 #include <rpc/xdr.h>
49 #include <rpc/auth.h>
50 
51 #include <rpc/rpc_com.h>
52 
53 /* gids compose part of a credential; there may not be more than 16 of them */
54 #define NGRPS 16
55 
56 /*
57  * XDR for unix authentication parameters.
58  */
59 bool_t
60 xdr_authunix_parms(XDR *xdrs, uint32_t *time, struct xucred *cred)
61 {
62 	uint32_t namelen;
63 	uint32_t ngroups, i;
64 	uint32_t junk;
65 	char hostbuf[MAXHOSTNAMELEN];
66 
67 	if (xdrs->x_op == XDR_ENCODE) {
68 		/*
69 		 * Restrict name length to 255 according to RFC 1057.
70 		 */
71 		getcredhostname(NULL, hostbuf, sizeof(hostbuf));
72 		namelen = strlen(hostbuf);
73 		if (namelen > 255)
74 			namelen = 255;
75 	} else {
76 		namelen = 0;
77 	}
78 	junk = 0;
79 
80 	if (!xdr_uint32_t(xdrs, time)
81 	    || !xdr_uint32_t(xdrs, &namelen))
82 		return (FALSE);
83 
84 	/*
85 	 * Ignore the hostname on decode.
86 	 */
87 	if (xdrs->x_op == XDR_ENCODE) {
88 		if (!xdr_opaque(xdrs, hostbuf, namelen))
89 			return (FALSE);
90 	} else {
91 		xdr_setpos(xdrs, xdr_getpos(xdrs) + RNDUP(namelen));
92 	}
93 
94 	if (!xdr_uint32_t(xdrs, &cred->cr_uid))
95 		return (FALSE);
96 	if (!xdr_uint32_t(xdrs, &cred->cr_groups[0]))
97 		return (FALSE);
98 
99 	if (xdrs->x_op == XDR_ENCODE) {
100 		ngroups = cred->cr_ngroups - 1;
101 		if (ngroups > NGRPS)
102 			ngroups = NGRPS;
103 	}
104 
105 	if (!xdr_uint32_t(xdrs, &ngroups))
106 		return (FALSE);
107 	for (i = 0; i < ngroups; i++) {
108 		if (i + 1 < ngroups_max + 1) {
109 			if (!xdr_uint32_t(xdrs, &cred->cr_groups[i + 1]))
110 				return (FALSE);
111 		} else {
112 			if (!xdr_uint32_t(xdrs, &junk))
113 				return (FALSE);
114 		}
115 	}
116 
117 	if (xdrs->x_op == XDR_DECODE) {
118 		if (ngroups + 1 > ngroups_max + 1)
119 			cred->cr_ngroups = ngroups_max + 1;
120 		else
121 			cred->cr_ngroups = ngroups + 1;
122 	}
123 
124 	return (TRUE);
125 }
126