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"
38static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
39#endif
40#include <sys/cdefs.h>
41__FBSDID("$FreeBSD$");
42
43/*
44 * svc_auth.c, Server-side rpc authenticator interface.
45 *
46 */
47
48#include "namespace.h"
49#include "reentrant.h"
50#include <sys/types.h>
51#include <rpc/rpc.h>
52#include <stdlib.h>
53#include "un-namespace.h"
54#include "mt_misc.h"
55
56/*
57 * svcauthsw is the bdevsw of server side authentication.
58 *
59 * Server side authenticators are called from authenticate by
60 * using the client auth struct flavor field to index into svcauthsw.
61 * The server auth flavors must implement a routine that looks
62 * like:
63 *
64 *	enum auth_stat
65 *	flavorx_auth(rqst, msg)
66 *		struct svc_req *rqst;
67 *		struct rpc_msg *msg;
68 *
69 */
70
71/* declarations to allow servers to specify new authentication flavors */
72struct authsvc {
73	int	flavor;
74	enum	auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
75	struct	authsvc	  *next;
76};
77static struct authsvc *Auths = NULL;
78
79struct svc_auth_ops svc_auth_null_ops;
80
81/*
82 * The call rpc message, msg has been obtained from the wire.  The msg contains
83 * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
84 * if the msg is successfully authenticated.  If AUTH_OK then the routine also
85 * does the following things:
86 * set rqst->rq_xprt->verf to the appropriate response verifier;
87 * sets rqst->rq_client_cred to the "cooked" form of the credentials.
88 *
89 * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
90 * its length is set appropriately.
91 *
92 * The caller still owns and is responsible for msg->u.cmb.cred and
93 * msg->u.cmb.verf.  The authentication system retains ownership of
94 * rqst->rq_client_cred, the cooked credentials.
95 *
96 * There is an assumption that any flavour less than AUTH_NULL is
97 * invalid.
98 */
99enum auth_stat
100_authenticate(struct svc_req *rqst, struct rpc_msg *msg)
101{
102	int cred_flavor;
103	struct authsvc *asp;
104	enum auth_stat dummy;
105
106/* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
107
108	rqst->rq_cred = msg->rm_call.cb_cred;
109	SVC_AUTH(rqst->rq_xprt).svc_ah_ops = &svc_auth_null_ops;
110	SVC_AUTH(rqst->rq_xprt).svc_ah_private = NULL;
111	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
112	rqst->rq_xprt->xp_verf.oa_length = 0;
113	cred_flavor = rqst->rq_cred.oa_flavor;
114	switch (cred_flavor) {
115	case AUTH_NULL:
116		dummy = _svcauth_null(rqst, msg);
117		return (dummy);
118	case AUTH_SYS:
119		dummy = _svcauth_unix(rqst, msg);
120		return (dummy);
121	case AUTH_SHORT:
122		dummy = _svcauth_short(rqst, msg);
123		return (dummy);
124#ifdef DES_BUILTIN
125	case AUTH_DES:
126		dummy = _svcauth_des(rqst, msg);
127		return (dummy);
128#endif
129	default:
130		break;
131	}
132
133	/* flavor doesn't match any of the builtin types, so try new ones */
134	mutex_lock(&authsvc_lock);
135	for (asp = Auths; asp; asp = asp->next) {
136		if (asp->flavor == cred_flavor) {
137			enum auth_stat as;
138
139			as = (*asp->handler)(rqst, msg);
140			mutex_unlock(&authsvc_lock);
141			return (as);
142		}
143	}
144	mutex_unlock(&authsvc_lock);
145
146	return (AUTH_REJECTEDCRED);
147}
148
149/*
150 * A set of null auth methods used by any authentication protocols
151 * that don't need to inspect or modify the message body.
152 */
153static bool_t
154svcauth_null_wrap(SVCAUTH *auth, XDR *xdrs, xdrproc_t xdr_func, caddr_t xdr_ptr)
155{
156
157	return (xdr_func(xdrs, xdr_ptr));
158}
159
160struct svc_auth_ops svc_auth_null_ops = {
161	svcauth_null_wrap,
162	svcauth_null_wrap,
163};
164
165/*ARGSUSED*/
166enum auth_stat
167_svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
168{
169	return (AUTH_OK);
170}
171
172/*
173 *  Allow the rpc service to register new authentication types that it is
174 *  prepared to handle.  When an authentication flavor is registered,
175 *  the flavor is checked against already registered values.  If not
176 *  registered, then a new Auths entry is added on the list.
177 *
178 *  There is no provision to delete a registration once registered.
179 *
180 *  This routine returns:
181 *	 0 if registration successful
182 *	 1 if flavor already registered
183 *	-1 if can't register (errno set)
184 */
185
186int
187svc_auth_reg(int cred_flavor,
188    enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *))
189{
190	struct authsvc *asp;
191
192	switch (cred_flavor) {
193	    case AUTH_NULL:
194	    case AUTH_SYS:
195	    case AUTH_SHORT:
196#ifdef DES_BUILTIN
197	    case AUTH_DES:
198#endif
199		/* already registered */
200		return (1);
201
202	    default:
203		mutex_lock(&authsvc_lock);
204		for (asp = Auths; asp; asp = asp->next) {
205			if (asp->flavor == cred_flavor) {
206				/* already registered */
207				mutex_unlock(&authsvc_lock);
208				return (1);
209			}
210		}
211
212		/* this is a new one, so go ahead and register it */
213		asp = mem_alloc(sizeof (*asp));
214		if (asp == NULL) {
215			mutex_unlock(&authsvc_lock);
216			return (-1);
217		}
218		asp->flavor = cred_flavor;
219		asp->handler = handler;
220		asp->next = Auths;
221		Auths = asp;
222		mutex_unlock(&authsvc_lock);
223		break;
224	}
225	return (0);
226}
227