xref: /freebsd/lib/libc/rpc/svc_auth_unix.c (revision f5463265955b829775bbb32e1fd0bc11dafc36ce)
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 /*
32  * svc_auth_unix.c
33  * Handles UNIX flavor authentication parameters on the service side of rpc.
34  * There are two svc auth implementations here: AUTH_UNIX and AUTH_SHORT.
35  * _svcauth_unix does full blown unix style uid,gid+gids auth,
36  * _svcauth_short uses a shorthand auth to index into a cache of longhand auths.
37  * Note: the shorthand has been gutted for efficiency.
38  *
39  * Copyright (C) 1984, Sun Microsystems, Inc.
40  */
41 
42 #include "namespace.h"
43 #include <assert.h>
44 #include <stdio.h>
45 #include <string.h>
46 
47 #include <rpc/rpc.h>
48 #include "un-namespace.h"
49 
50 /*
51  * Unix longhand authenticator
52  */
53 enum auth_stat
54 _svcauth_unix(struct svc_req *rqst, struct rpc_msg *msg)
55 {
56 	enum auth_stat stat;
57 	XDR xdrs;
58 	struct authunix_parms *aup;
59 	int32_t *buf;
60 	struct area {
61 		struct authunix_parms area_aup;
62 		char area_machname[MAX_MACHINE_NAME+1];
63 		u_int area_gids[NGRPS];
64 	} *area;
65 	u_int auth_len;
66 	size_t str_len, gid_len;
67 	u_int i;
68 
69 	assert(rqst != NULL);
70 	assert(msg != NULL);
71 
72 	area = (struct area *) rqst->rq_clntcred;
73 	aup = &area->area_aup;
74 	aup->aup_machname = area->area_machname;
75 	aup->aup_gids = area->area_gids;
76 	auth_len = (u_int)msg->rm_call.cb_cred.oa_length;
77 	xdrmem_create(&xdrs, msg->rm_call.cb_cred.oa_base, auth_len,XDR_DECODE);
78 	buf = XDR_INLINE(&xdrs, auth_len);
79 	if (buf != NULL) {
80 		aup->aup_time = IXDR_GET_INT32(buf);
81 		str_len = (size_t)IXDR_GET_U_INT32(buf);
82 		if (str_len > MAX_MACHINE_NAME) {
83 			stat = AUTH_BADCRED;
84 			goto done;
85 		}
86 		memmove(aup->aup_machname, buf, str_len);
87 		aup->aup_machname[str_len] = 0;
88 		str_len = RNDUP(str_len);
89 		buf += str_len / sizeof (int32_t);
90 		aup->aup_uid = (int)IXDR_GET_INT32(buf);
91 		aup->aup_gid = (int)IXDR_GET_INT32(buf);
92 		gid_len = (size_t)IXDR_GET_U_INT32(buf);
93 		if (gid_len > NGRPS) {
94 			stat = AUTH_BADCRED;
95 			goto done;
96 		}
97 		aup->aup_len = gid_len;
98 		for (i = 0; i < gid_len; i++) {
99 			aup->aup_gids[i] = (int)IXDR_GET_INT32(buf);
100 		}
101 		/*
102 		 * five is the smallest unix credentials structure -
103 		 * timestamp, hostname len (0), uid, gid, and gids len (0).
104 		 */
105 		if ((5 + gid_len) * BYTES_PER_XDR_UNIT + str_len > auth_len) {
106 			(void) printf("bad auth_len gid %ld str %ld auth %u\n",
107 			    (long)gid_len, (long)str_len, auth_len);
108 			stat = AUTH_BADCRED;
109 			goto done;
110 		}
111 	} else if (! xdr_authunix_parms(&xdrs, aup)) {
112 		xdrs.x_op = XDR_FREE;
113 		(void)xdr_authunix_parms(&xdrs, aup);
114 		stat = AUTH_BADCRED;
115 		goto done;
116 	}
117 
118        /* get the verifier */
119 	if ((u_int)msg->rm_call.cb_verf.oa_length) {
120 		rqst->rq_xprt->xp_verf.oa_flavor =
121 			msg->rm_call.cb_verf.oa_flavor;
122 		rqst->rq_xprt->xp_verf.oa_base =
123 			msg->rm_call.cb_verf.oa_base;
124 		rqst->rq_xprt->xp_verf.oa_length =
125 			msg->rm_call.cb_verf.oa_length;
126 	} else {
127 		rqst->rq_xprt->xp_verf.oa_flavor = AUTH_NULL;
128 		rqst->rq_xprt->xp_verf.oa_length = 0;
129 	}
130 	stat = AUTH_OK;
131 done:
132 	XDR_DESTROY(&xdrs);
133 	return (stat);
134 }
135 
136 
137 /*
138  * Shorthand unix authenticator
139  * Looks up longhand in a cache.
140  */
141 /*ARGSUSED*/
142 enum auth_stat
143 _svcauth_short(struct svc_req *rqst, struct rpc_msg *msg)
144 {
145 	return (AUTH_REJECTEDCRED);
146 }
147