xref: /freebsd/sys/rpc/svc_auth.c (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
1 /*	$NetBSD: svc_auth.c,v 1.12 2000/07/06 03:10:35 christos 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  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #ident	"@(#)svc_auth.c	1.16	94/04/24 SMI"
38 static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
39 #endif
40 #include <sys/cdefs.h>
41 /*
42  * svc_auth.c, Server-side rpc authenticator interface.
43  *
44  */
45 
46 #include <sys/param.h>
47 #include <sys/lock.h>
48 #include <sys/mutex.h>
49 #include <sys/proc.h>
50 #include <sys/systm.h>
51 #include <sys/jail.h>
52 #include <sys/ucred.h>
53 
54 #include <rpc/rpc.h>
55 #include <rpc/rpcsec_tls.h>
56 
57 static enum auth_stat (*_svcauth_rpcsec_gss)(struct svc_req *,
58     struct rpc_msg *) = NULL;
59 static int (*_svcauth_rpcsec_gss_getcred)(struct svc_req *,
60     struct ucred **, int *);
61 
62 static const struct svc_auth_ops svc_auth_null_ops;
63 
64 /*
65  * The call rpc message, msg has been obtained from the wire.  The msg contains
66  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
67  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
68  * does the following things:
69  * set rqst->rq_xprt->verf to the appropriate response verifier;
70  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
71  *
72  * NB: rqst->rq_cxprt->verf must be pre-allocated;
73  * its length is set appropriately.
74  *
75  * The caller still owns and is responsible for msg->u.cmb.cred and
76  * msg->u.cmb.verf.  The authentication system retains ownership of
77  * rqst->rq_client_cred, the cooked credentials.
78  *
79  * There is an assumption that any flavour less than AUTH_NULL is
80  * invalid.
81  */
82 enum auth_stat
83 _authenticate(struct svc_req *rqst, struct rpc_msg *msg)
84 {
85 	int cred_flavor;
86 	enum auth_stat dummy;
87 
88 	rqst->rq_cred = msg->rm_call.cb_cred;
89 	rqst->rq_auth.svc_ah_ops = &svc_auth_null_ops;
90 	rqst->rq_auth.svc_ah_private = NULL;
91 	cred_flavor = rqst->rq_cred.oa_flavor;
92 	switch (cred_flavor) {
93 	case AUTH_NULL:
94 		dummy = _svcauth_null(rqst, msg);
95 		return (dummy);
96 	case AUTH_SYS:
97 		if ((rqst->rq_xprt->xp_tls & RPCTLS_FLAGS_DISABLED) != 0)
98 			return (AUTH_REJECTEDCRED);
99 		dummy = _svcauth_unix(rqst, msg);
100 		return (dummy);
101 	case AUTH_SHORT:
102 		if ((rqst->rq_xprt->xp_tls & RPCTLS_FLAGS_DISABLED) != 0)
103 			return (AUTH_REJECTEDCRED);
104 		dummy = _svcauth_short(rqst, msg);
105 		return (dummy);
106 	case RPCSEC_GSS:
107 		if ((rqst->rq_xprt->xp_tls & RPCTLS_FLAGS_DISABLED) != 0)
108 			return (AUTH_REJECTEDCRED);
109 		if (!_svcauth_rpcsec_gss)
110 			return (AUTH_REJECTEDCRED);
111 		dummy = _svcauth_rpcsec_gss(rqst, msg);
112 		return (dummy);
113 	case AUTH_TLS:
114 		dummy = _svcauth_rpcsec_tls(rqst, msg);
115 		return (dummy);
116 	default:
117 		break;
118 	}
119 
120 	return (AUTH_REJECTEDCRED);
121 }
122 
123 /*
124  * A set of null auth methods used by any authentication protocols
125  * that don't need to inspect or modify the message body.
126  */
127 static bool_t
128 svcauth_null_wrap(SVCAUTH *auth, struct mbuf **mp)
129 {
130 
131 	return (TRUE);
132 }
133 
134 static bool_t
135 svcauth_null_unwrap(SVCAUTH *auth, struct mbuf **mp)
136 {
137 
138 	return (TRUE);
139 }
140 
141 static void
142 svcauth_null_release(SVCAUTH *auth)
143 {
144 
145 }
146 
147 static const struct svc_auth_ops svc_auth_null_ops = {
148 	.svc_ah_wrap = svcauth_null_wrap,
149 	.svc_ah_unwrap = svcauth_null_unwrap,
150 	.svc_ah_release = svcauth_null_release,
151 };
152 
153 /*ARGSUSED*/
154 enum auth_stat
155 _svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
156 {
157 
158 	rqst->rq_verf = _null_auth;
159 	return (AUTH_OK);
160 }
161 
162 int
163 svc_auth_reg(int flavor,
164     enum auth_stat (*svcauth)(struct svc_req *, struct rpc_msg *),
165     int (*getcred)(struct svc_req *, struct ucred **, int *))
166 {
167 
168 	if (flavor == RPCSEC_GSS) {
169 		_svcauth_rpcsec_gss = svcauth;
170 		_svcauth_rpcsec_gss_getcred = getcred;
171 	}
172 	return (TRUE);
173 }
174 
175 int
176 svc_getcred(struct svc_req *rqst, struct ucred **crp, int *flavorp)
177 {
178 	struct ucred *cr = NULL;
179 	int flavor;
180 	struct xucred *xcr;
181 	SVCXPRT *xprt = rqst->rq_xprt;
182 
183 	flavor = rqst->rq_cred.oa_flavor;
184 	if (flavorp)
185 		*flavorp = flavor;
186 
187 	/*
188 	 * If there are credentials acquired via a TLS
189 	 * certificate for this TCP connection, use those
190 	 * instead of what is in the RPC header.
191 	 */
192 	if ((xprt->xp_tls & (RPCTLS_FLAGS_CERTUSER |
193 	    RPCTLS_FLAGS_DISABLED)) == RPCTLS_FLAGS_CERTUSER &&
194 	    flavor == AUTH_UNIX) {
195 		cr = crget();
196 		cr->cr_uid = cr->cr_ruid = cr->cr_svuid = xprt->xp_uid;
197 		crsetgroups(cr, xprt->xp_ngrps, xprt->xp_gidp);
198 		cr->cr_rgid = cr->cr_svgid = xprt->xp_gidp[0];
199 		cr->cr_prison = curthread->td_ucred->cr_prison;
200 		prison_hold(cr->cr_prison);
201 		*crp = cr;
202 		return (TRUE);
203 	}
204 
205 	switch (flavor) {
206 	case AUTH_UNIX:
207 		xcr = (struct xucred *) rqst->rq_clntcred;
208 		cr = crget();
209 		cr->cr_uid = cr->cr_ruid = cr->cr_svuid = xcr->cr_uid;
210 		crsetgroups(cr, xcr->cr_ngroups, xcr->cr_groups);
211 		cr->cr_rgid = cr->cr_svgid = cr->cr_groups[0];
212 		cr->cr_prison = curthread->td_ucred->cr_prison;
213 		prison_hold(cr->cr_prison);
214 		*crp = cr;
215 		return (TRUE);
216 
217 	case RPCSEC_GSS:
218 		if (!_svcauth_rpcsec_gss_getcred)
219 			return (FALSE);
220 		return (_svcauth_rpcsec_gss_getcred(rqst, crp, flavorp));
221 
222 	default:
223 		return (FALSE);
224 	}
225 }
226 
227