xref: /freebsd/sys/rpc/svc_auth_unix.c (revision eb69d1f144a6fcc765d1b9d44a5ae8082353e70b)
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 *sccsid2 = "@(#)svc_auth_unix.c 1.28 88/02/08 Copyr 1984 Sun Micro";
33 static char *sccsid = "@(#)svc_auth_unix.c	2.3 88/08/01 4.0 RPCSRC";
34 #endif
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 /*
39  * svc_auth_unix.c
40  * Handles UNIX flavor authentication parameters on the service side of rpc.
41  * There are two svc auth implementations here: AUTH_UNIX and AUTH_SHORT.
42  * _svcauth_unix does full blown unix style uid,gid+gids auth,
43  * _svcauth_short uses a shorthand auth to index into a cache of longhand auths.
44  * Note: the shorthand has been gutted for efficiency.
45  *
46  * Copyright (C) 1984, Sun Microsystems, Inc.
47  */
48 
49 #include <sys/param.h>
50 #include <sys/lock.h>
51 #include <sys/mutex.h>
52 #include <sys/systm.h>
53 #include <sys/ucred.h>
54 
55 #include <rpc/rpc.h>
56 
57 #include <rpc/rpc_com.h>
58 
59 #define MAX_MACHINE_NAME	255
60 #define NGRPS			16
61 
62 /*
63  * Unix longhand authenticator
64  */
65 enum auth_stat
66 _svcauth_unix(struct svc_req *rqst, struct rpc_msg *msg)
67 {
68 	enum auth_stat stat;
69 	XDR xdrs;
70 	int32_t *buf;
71 	uint32_t time;
72 	struct xucred *xcr;
73 	u_int auth_len;
74 	size_t str_len, gid_len;
75 	u_int i;
76 
77 	xcr = rqst->rq_clntcred;
78 	auth_len = (u_int)msg->rm_call.cb_cred.oa_length;
79 	xdrmem_create(&xdrs, msg->rm_call.cb_cred.oa_base, auth_len,
80 	    XDR_DECODE);
81 	buf = XDR_INLINE(&xdrs, auth_len);
82 	if (buf != NULL) {
83 		time = IXDR_GET_UINT32(buf);
84 		str_len = (size_t)IXDR_GET_UINT32(buf);
85 		if (str_len > MAX_MACHINE_NAME) {
86 			stat = AUTH_BADCRED;
87 			goto done;
88 		}
89 		str_len = RNDUP(str_len);
90 		buf += str_len / sizeof (int32_t);
91 		xcr->cr_uid = IXDR_GET_UINT32(buf);
92 		xcr->cr_groups[0] = IXDR_GET_UINT32(buf);
93 		gid_len = (size_t)IXDR_GET_UINT32(buf);
94 		if (gid_len > NGRPS) {
95 			stat = AUTH_BADCRED;
96 			goto done;
97 		}
98 		for (i = 0; i < gid_len; i++) {
99 			if (i + 1 < XU_NGROUPS)
100 				xcr->cr_groups[i + 1] = IXDR_GET_INT32(buf);
101 			else
102 				buf++;
103 		}
104 		if (gid_len + 1 > XU_NGROUPS)
105 			xcr->cr_ngroups = XU_NGROUPS;
106 		else
107 			xcr->cr_ngroups = gid_len + 1;
108 
109 		/*
110 		 * five is the smallest unix credentials structure -
111 		 * timestamp, hostname len (0), uid, gid, and gids len (0).
112 		 */
113 		if ((5 + gid_len) * BYTES_PER_XDR_UNIT + str_len > auth_len) {
114 			(void) printf("bad auth_len gid %ld str %ld auth %u\n",
115 			    (long)gid_len, (long)str_len, auth_len);
116 			stat = AUTH_BADCRED;
117 			goto done;
118 		}
119 	} else if (! xdr_authunix_parms(&xdrs, &time, xcr)) {
120 		stat = AUTH_BADCRED;
121 		goto done;
122 	}
123 
124 	rqst->rq_verf = _null_auth;
125 	stat = AUTH_OK;
126 done:
127 	XDR_DESTROY(&xdrs);
128 
129 	return (stat);
130 }
131 
132 
133 /*
134  * Shorthand unix authenticator
135  * Looks up longhand in a cache.
136  */
137 /*ARGSUSED*/
138 enum auth_stat
139 _svcauth_short(rqst, msg)
140 	struct svc_req *rqst;
141 	struct rpc_msg *msg;
142 {
143 	return (AUTH_REJECTEDCRED);
144 }
145