xref: /freebsd/lib/libc/rpc/svc_auth.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
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"
36 static 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 */
70 struct authsvc {
71 	int	flavor;
72 	enum	auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
73 	struct	authsvc	  *next;
74 };
75 static struct authsvc *Auths = NULL;
76 
77 struct 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  */
97 enum auth_stat
98 _authenticate(rqst, msg)
99 	struct svc_req *rqst;
100 	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  */
153 static bool_t
154 svcauth_null_wrap(auth, xdrs, xdr_func, xdr_ptr)
155 	SVCAUTH *auth;
156 	XDR *xdrs;
157 	xdrproc_t xdr_func;
158 	caddr_t xdr_ptr;
159 {
160 
161 	return (xdr_func(xdrs, xdr_ptr));
162 }
163 
164 struct svc_auth_ops svc_auth_null_ops = {
165 	svcauth_null_wrap,
166 	svcauth_null_wrap,
167 };
168 
169 /*ARGSUSED*/
170 enum auth_stat
171 _svcauth_null(rqst, msg)
172 	struct svc_req *rqst;
173 	struct rpc_msg *msg;
174 {
175 	return (AUTH_OK);
176 }
177 
178 /*
179  *  Allow the rpc service to register new authentication types that it is
180  *  prepared to handle.  When an authentication flavor is registered,
181  *  the flavor is checked against already registered values.  If not
182  *  registered, then a new Auths entry is added on the list.
183  *
184  *  There is no provision to delete a registration once registered.
185  *
186  *  This routine returns:
187  *	 0 if registration successful
188  *	 1 if flavor already registered
189  *	-1 if can't register (errno set)
190  */
191 
192 int
193 svc_auth_reg(cred_flavor, handler)
194 	int cred_flavor;
195 	enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
196 {
197 	struct authsvc *asp;
198 
199 	switch (cred_flavor) {
200 	    case AUTH_NULL:
201 	    case AUTH_SYS:
202 	    case AUTH_SHORT:
203 #ifdef DES_BUILTIN
204 	    case AUTH_DES:
205 #endif
206 		/* already registered */
207 		return (1);
208 
209 	    default:
210 		mutex_lock(&authsvc_lock);
211 		for (asp = Auths; asp; asp = asp->next) {
212 			if (asp->flavor == cred_flavor) {
213 				/* already registered */
214 				mutex_unlock(&authsvc_lock);
215 				return (1);
216 			}
217 		}
218 
219 		/* this is a new one, so go ahead and register it */
220 		asp = mem_alloc(sizeof (*asp));
221 		if (asp == NULL) {
222 			mutex_unlock(&authsvc_lock);
223 			return (-1);
224 		}
225 		asp->flavor = cred_flavor;
226 		asp->handler = handler;
227 		asp->next = Auths;
228 		Auths = asp;
229 		mutex_unlock(&authsvc_lock);
230 		break;
231 	}
232 	return (0);
233 }
234