xref: /illumos-gate/usr/src/lib/libnsl/rpc/svc_auth_loopb.c (revision ce17336ed725d3b7fdff67bf0a0ee2b55018fec6)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 
23 /*
24  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25  * Copyright 2017 Joyent Inc
26  * Use is subject to license terms.
27  */
28 
29 /*
30  * Handles the loopback UNIX flavor authentication parameters on the
31  * service side of rpc.
32  */
33 
34 #include "mt.h"
35 #include <stdio.h>
36 #include <rpc/rpc.h>
37 #include <syslog.h>
38 #include <sys/types.h>
39 #include <sys/debug.h>
40 
41 /*
42  * NOTE: this has to fit inside RQCRED_SIZE bytes. If you update this struct,
43  * double-check it still fits.
44  */
45 struct authlpbk_area {
46 	struct authsys_parms area_aup;
47 	char area_machname[MAX_MACHINE_NAME+1];
48 	gid_t area_gids[NGRPS_LOOPBACK];
49 };
50 CTASSERT(sizeof (struct authlpbk_area) <= RQCRED_SIZE);
51 
52 /*
53  * Loopback system (Unix) longhand authenticator
54  */
55 enum auth_stat
56 __svcauth_loopback(struct svc_req *rqst, struct rpc_msg *msg)
57 {
58 	struct authsys_parms *aup;
59 	int32_t *buf;
60 	struct authlpbk_area *area;
61 	uint_t auth_len;
62 	uint_t str_len, gid_len;
63 	int i;
64 
65 	/* LINTED pointer cast */
66 	area = (struct authlpbk_area *)rqst->rq_clntcred;
67 	aup = &area->area_aup;
68 	aup->aup_machname = area->area_machname;
69 	aup->aup_gids = area->area_gids;
70 	auth_len = msg->rm_call.cb_cred.oa_length;
71 	if (auth_len == 0)
72 		return (AUTH_BADCRED);
73 
74 	/* LINTED pointer cast */
75 	buf = (int32_t *)msg->rm_call.cb_cred.oa_base;
76 
77 	aup->aup_time = IXDR_GET_INT32(buf);
78 	str_len = IXDR_GET_U_INT32(buf);
79 	if (str_len > MAX_MACHINE_NAME)
80 		return (AUTH_BADCRED);
81 	if (str_len > auth_len)
82 		return (AUTH_BADCRED);
83 	(void) memcpy(aup->aup_machname, buf, str_len);
84 	aup->aup_machname[str_len] = 0;
85 	str_len = RNDUP(str_len);
86 	buf += str_len / sizeof (int);
87 	aup->aup_uid = IXDR_GET_INT32(buf);
88 	aup->aup_gid = IXDR_GET_INT32(buf);
89 	gid_len = IXDR_GET_U_INT32(buf);
90 	if (gid_len > NGRPS_LOOPBACK)
91 		return (AUTH_BADCRED);
92 	/*
93 	 * five is the smallest unix credentials structure -
94 	 * timestamp, hostname len (0), uid, gid, and gids len (0).
95 	 */
96 	if ((5 + gid_len) * BYTES_PER_XDR_UNIT + str_len > auth_len)
97 		return (AUTH_BADCRED);
98 
99 	aup->aup_len = gid_len;
100 	for (i = 0; i < gid_len; i++) {
101 		aup->aup_gids[i] = (gid_t)IXDR_GET_INT32(buf);
102 	}
103 
104 	rqst->rq_xprt->xp_verf.oa_flavor = AUTH_NULL;
105 	rqst->rq_xprt->xp_verf.oa_length = 0;
106 
107 	return (AUTH_OK);
108 }
109