authunix_prot.c revision 330897 
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#if defined(LIBC_SCCS) && !defined(lint)
34static char *sccsid2 = "@(#)authunix_prot.c 1.15 87/08/11 Copyr 1984 Sun Micro";
35static char *sccsid = "@(#)authunix_prot.c	2.1 88/07/29 4.0 RPCSRC";
36#endif
37#include <sys/cdefs.h>
38__FBSDID("$FreeBSD: stable/11/sys/rpc/authunix_prot.c 330897 2018-03-14 03:19:51Z eadler $");
39
40/*
41 * authunix_prot.c
42 * XDR for UNIX style authentication parameters for RPC
43 *
44 * Copyright (C) 1984, Sun Microsystems, Inc.
45 */
46
47#include <sys/param.h>
48#include <sys/jail.h>
49#include <sys/kernel.h>
50#include <sys/systm.h>
51#include <sys/ucred.h>
52
53#include <rpc/types.h>
54#include <rpc/xdr.h>
55#include <rpc/auth.h>
56
57#include <rpc/rpc_com.h>
58
59/* gids compose part of a credential; there may not be more than 16 of them */
60#define NGRPS 16
61
62/*
63 * XDR for unix authentication parameters.
64 */
65bool_t
66xdr_authunix_parms(XDR *xdrs, uint32_t *time, struct xucred *cred)
67{
68	uint32_t namelen;
69	uint32_t ngroups, i;
70	uint32_t junk;
71	char hostbuf[MAXHOSTNAMELEN];
72
73	if (xdrs->x_op == XDR_ENCODE) {
74		/*
75		 * Restrict name length to 255 according to RFC 1057.
76		 */
77		getcredhostname(NULL, hostbuf, sizeof(hostbuf));
78		namelen = strlen(hostbuf);
79		if (namelen > 255)
80			namelen = 255;
81	} else {
82		namelen = 0;
83	}
84	junk = 0;
85
86	if (!xdr_uint32_t(xdrs, time)
87	    || !xdr_uint32_t(xdrs, &namelen))
88		return (FALSE);
89
90	/*
91	 * Ignore the hostname on decode.
92	 */
93	if (xdrs->x_op == XDR_ENCODE) {
94		if (!xdr_opaque(xdrs, hostbuf, namelen))
95			return (FALSE);
96	} else {
97		xdr_setpos(xdrs, xdr_getpos(xdrs) + RNDUP(namelen));
98	}
99
100	if (!xdr_uint32_t(xdrs, &cred->cr_uid))
101		return (FALSE);
102	if (!xdr_uint32_t(xdrs, &cred->cr_groups[0]))
103		return (FALSE);
104
105	if (xdrs->x_op == XDR_ENCODE) {
106		ngroups = cred->cr_ngroups - 1;
107		if (ngroups > NGRPS)
108			ngroups = NGRPS;
109	}
110
111	if (!xdr_uint32_t(xdrs, &ngroups))
112		return (FALSE);
113	for (i = 0; i < ngroups; i++) {
114		if (i + 1 < ngroups_max + 1) {
115			if (!xdr_uint32_t(xdrs, &cred->cr_groups[i + 1]))
116				return (FALSE);
117		} else {
118			if (!xdr_uint32_t(xdrs, &junk))
119				return (FALSE);
120		}
121	}
122
123	if (xdrs->x_op == XDR_DECODE) {
124		if (ngroups + 1 > ngroups_max + 1)
125			cred->cr_ngroups = ngroups_max + 1;
126		else
127			cred->cr_ngroups = ngroups + 1;
128	}
129
130	return (TRUE);
131}
132