1/*	$NetBSD: svc_auth.c,v 1.12 2000/07/06 03:10:35 christos Exp $	*/
2
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 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
32 */
33
34#if defined(LIBC_SCCS) && !defined(lint)
35#ident	"@(#)svc_auth.c	1.16	94/04/24 SMI"
36static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
37#endif
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41/*
42 * svc_auth.c, Server-side rpc authenticator interface.
43 *
44 */
45
46#include "namespace.h"
47#include "reentrant.h"
48#include <sys/types.h>
49#include <rpc/rpc.h>
50#include <stdlib.h>
51#include "un-namespace.h"
52#include "mt_misc.h"
53
54/*
55 * svcauthsw is the bdevsw of server side authentication.
56 *
57 * Server side authenticators are called from authenticate by
58 * using the client auth struct flavor field to index into svcauthsw.
59 * The server auth flavors must implement a routine that looks
60 * like:
61 *
62 *	enum auth_stat
63 *	flavorx_auth(rqst, msg)
64 *		struct svc_req *rqst;
65 *		struct rpc_msg *msg;
66 *
67 */
68
69/* declarations to allow servers to specify new authentication flavors */
70struct authsvc {
71	int	flavor;
72	enum	auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
73	struct	authsvc	  *next;
74};
75static struct authsvc *Auths = NULL;
76
77struct svc_auth_ops svc_auth_null_ops;
78
79/*
80 * The call rpc message, msg has been obtained from the wire.  The msg contains
81 * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
82 * if the msg is successfully authenticated.  If AUTH_OK then the routine also
83 * does the following things:
84 * set rqst->rq_xprt->verf to the appropriate response verifier;
85 * sets rqst->rq_client_cred to the "cooked" form of the credentials.
86 *
87 * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
88 * its length is set appropriately.
89 *
90 * The caller still owns and is responsible for msg->u.cmb.cred and
91 * msg->u.cmb.verf.  The authentication system retains ownership of
92 * rqst->rq_client_cred, the cooked credentials.
93 *
94 * There is an assumption that any flavour less than AUTH_NULL is
95 * invalid.
96 */
97enum auth_stat
98_authenticate(struct svc_req *rqst, struct rpc_msg *msg)
99{
100	int cred_flavor;
101	struct authsvc *asp;
102	enum auth_stat dummy;
103
104/* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
105
106	rqst->rq_cred = msg->rm_call.cb_cred;
107	SVC_AUTH(rqst->rq_xprt).svc_ah_ops = &svc_auth_null_ops;
108	SVC_AUTH(rqst->rq_xprt).svc_ah_private = NULL;
109	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
110	rqst->rq_xprt->xp_verf.oa_length = 0;
111	cred_flavor = rqst->rq_cred.oa_flavor;
112	switch (cred_flavor) {
113	case AUTH_NULL:
114		dummy = _svcauth_null(rqst, msg);
115		return (dummy);
116	case AUTH_SYS:
117		dummy = _svcauth_unix(rqst, msg);
118		return (dummy);
119	case AUTH_SHORT:
120		dummy = _svcauth_short(rqst, msg);
121		return (dummy);
122#ifdef DES_BUILTIN
123	case AUTH_DES:
124		dummy = _svcauth_des(rqst, msg);
125		return (dummy);
126#endif
127	default:
128		break;
129	}
130
131	/* flavor doesn't match any of the builtin types, so try new ones */
132	mutex_lock(&authsvc_lock);
133	for (asp = Auths; asp; asp = asp->next) {
134		if (asp->flavor == cred_flavor) {
135			enum auth_stat as;
136
137			as = (*asp->handler)(rqst, msg);
138			mutex_unlock(&authsvc_lock);
139			return (as);
140		}
141	}
142	mutex_unlock(&authsvc_lock);
143
144	return (AUTH_REJECTEDCRED);
145}
146
147/*
148 * A set of null auth methods used by any authentication protocols
149 * that don't need to inspect or modify the message body.
150 */
151static bool_t
152svcauth_null_wrap(SVCAUTH *auth, XDR *xdrs, xdrproc_t xdr_func, caddr_t xdr_ptr)
153{
154
155	return (xdr_func(xdrs, xdr_ptr));
156}
157
158struct svc_auth_ops svc_auth_null_ops = {
159	svcauth_null_wrap,
160	svcauth_null_wrap,
161};
162
163/*ARGSUSED*/
164enum auth_stat
165_svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
166{
167	return (AUTH_OK);
168}
169
170/*
171 *  Allow the rpc service to register new authentication types that it is
172 *  prepared to handle.  When an authentication flavor is registered,
173 *  the flavor is checked against already registered values.  If not
174 *  registered, then a new Auths entry is added on the list.
175 *
176 *  There is no provision to delete a registration once registered.
177 *
178 *  This routine returns:
179 *	 0 if registration successful
180 *	 1 if flavor already registered
181 *	-1 if can't register (errno set)
182 */
183
184int
185svc_auth_reg(int cred_flavor,
186    enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *))
187{
188	struct authsvc *asp;
189
190	switch (cred_flavor) {
191	    case AUTH_NULL:
192	    case AUTH_SYS:
193	    case AUTH_SHORT:
194#ifdef DES_BUILTIN
195	    case AUTH_DES:
196#endif
197		/* already registered */
198		return (1);
199
200	    default:
201		mutex_lock(&authsvc_lock);
202		for (asp = Auths; asp; asp = asp->next) {
203			if (asp->flavor == cred_flavor) {
204				/* already registered */
205				mutex_unlock(&authsvc_lock);
206				return (1);
207			}
208		}
209
210		/* this is a new one, so go ahead and register it */
211		asp = mem_alloc(sizeof (*asp));
212		if (asp == NULL) {
213			mutex_unlock(&authsvc_lock);
214			return (-1);
215		}
216		asp->flavor = cred_flavor;
217		asp->handler = handler;
218		asp->next = Auths;
219		Auths = asp;
220		mutex_unlock(&authsvc_lock);
221		break;
222	}
223	return (0);
224}
225