xref: /freebsd/lib/libc/rpc/svc_auth.c (revision 641a6cfb86023499caafe26a4d821a0b885cf00b)
1 /*	$NetBSD: svc_auth.c,v 1.12 2000/07/06 03:10:35 christos Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 /*
32  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
33  */
34 
35 #if defined(LIBC_SCCS) && !defined(lint)
36 #ident	"@(#)svc_auth.c	1.16	94/04/24 SMI"
37 static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
38 #endif
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 /*
43  * svc_auth.c, Server-side rpc authenticator interface.
44  *
45  */
46 
47 #include "namespace.h"
48 #include "reentrant.h"
49 #include <sys/types.h>
50 #include <rpc/rpc.h>
51 #include <stdlib.h>
52 #include "un-namespace.h"
53 #include "mt_misc.h"
54 
55 /*
56  * svcauthsw is the bdevsw of server side authentication.
57  *
58  * Server side authenticators are called from authenticate by
59  * using the client auth struct flavor field to index into svcauthsw.
60  * The server auth flavors must implement a routine that looks
61  * like:
62  *
63  *	enum auth_stat
64  *	flavorx_auth(rqst, msg)
65  *		struct svc_req *rqst;
66  *		struct rpc_msg *msg;
67  *
68  */
69 
70 /* declarations to allow servers to specify new authentication flavors */
71 struct authsvc {
72 	int	flavor;
73 	enum	auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
74 	struct	authsvc	  *next;
75 };
76 static struct authsvc *Auths = NULL;
77 
78 struct svc_auth_ops svc_auth_null_ops;
79 
80 /*
81  * The call rpc message, msg has been obtained from the wire.  The msg contains
82  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
83  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
84  * does the following things:
85  * set rqst->rq_xprt->verf to the appropriate response verifier;
86  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
87  *
88  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
89  * its length is set appropriately.
90  *
91  * The caller still owns and is responsible for msg->u.cmb.cred and
92  * msg->u.cmb.verf.  The authentication system retains ownership of
93  * rqst->rq_client_cred, the cooked credentials.
94  *
95  * There is an assumption that any flavour less than AUTH_NULL is
96  * invalid.
97  */
98 enum auth_stat
99 _authenticate(rqst, msg)
100 	struct svc_req *rqst;
101 	struct rpc_msg *msg;
102 {
103 	int cred_flavor;
104 	struct authsvc *asp;
105 	enum auth_stat dummy;
106 
107 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
108 
109 	rqst->rq_cred = msg->rm_call.cb_cred;
110 	SVC_AUTH(rqst->rq_xprt).svc_ah_ops = &svc_auth_null_ops;
111 	SVC_AUTH(rqst->rq_xprt).svc_ah_private = NULL;
112 	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
113 	rqst->rq_xprt->xp_verf.oa_length = 0;
114 	cred_flavor = rqst->rq_cred.oa_flavor;
115 	switch (cred_flavor) {
116 	case AUTH_NULL:
117 		dummy = _svcauth_null(rqst, msg);
118 		return (dummy);
119 	case AUTH_SYS:
120 		dummy = _svcauth_unix(rqst, msg);
121 		return (dummy);
122 	case AUTH_SHORT:
123 		dummy = _svcauth_short(rqst, msg);
124 		return (dummy);
125 #ifdef DES_BUILTIN
126 	case AUTH_DES:
127 		dummy = _svcauth_des(rqst, msg);
128 		return (dummy);
129 #endif
130 	default:
131 		break;
132 	}
133 
134 	/* flavor doesn't match any of the builtin types, so try new ones */
135 	mutex_lock(&authsvc_lock);
136 	for (asp = Auths; asp; asp = asp->next) {
137 		if (asp->flavor == cred_flavor) {
138 			enum auth_stat as;
139 
140 			as = (*asp->handler)(rqst, msg);
141 			mutex_unlock(&authsvc_lock);
142 			return (as);
143 		}
144 	}
145 	mutex_unlock(&authsvc_lock);
146 
147 	return (AUTH_REJECTEDCRED);
148 }
149 
150 /*
151  * A set of null auth methods used by any authentication protocols
152  * that don't need to inspect or modify the message body.
153  */
154 static bool_t
155 svcauth_null_wrap(auth, xdrs, xdr_func, xdr_ptr)
156 	SVCAUTH *auth;
157 	XDR *xdrs;
158 	xdrproc_t xdr_func;
159 	caddr_t xdr_ptr;
160 {
161 
162 	return (xdr_func(xdrs, xdr_ptr));
163 }
164 
165 struct svc_auth_ops svc_auth_null_ops = {
166 	svcauth_null_wrap,
167 	svcauth_null_wrap,
168 };
169 
170 /*ARGSUSED*/
171 enum auth_stat
172 _svcauth_null(rqst, msg)
173 	struct svc_req *rqst;
174 	struct rpc_msg *msg;
175 {
176 	return (AUTH_OK);
177 }
178 
179 /*
180  *  Allow the rpc service to register new authentication types that it is
181  *  prepared to handle.  When an authentication flavor is registered,
182  *  the flavor is checked against already registered values.  If not
183  *  registered, then a new Auths entry is added on the list.
184  *
185  *  There is no provision to delete a registration once registered.
186  *
187  *  This routine returns:
188  *	 0 if registration successful
189  *	 1 if flavor already registered
190  *	-1 if can't register (errno set)
191  */
192 
193 int
194 svc_auth_reg(cred_flavor, handler)
195 	int cred_flavor;
196 	enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
197 {
198 	struct authsvc *asp;
199 
200 	switch (cred_flavor) {
201 	    case AUTH_NULL:
202 	    case AUTH_SYS:
203 	    case AUTH_SHORT:
204 #ifdef DES_BUILTIN
205 	    case AUTH_DES:
206 #endif
207 		/* already registered */
208 		return (1);
209 
210 	    default:
211 		mutex_lock(&authsvc_lock);
212 		for (asp = Auths; asp; asp = asp->next) {
213 			if (asp->flavor == cred_flavor) {
214 				/* already registered */
215 				mutex_unlock(&authsvc_lock);
216 				return (1);
217 			}
218 		}
219 
220 		/* this is a new one, so go ahead and register it */
221 		asp = mem_alloc(sizeof (*asp));
222 		if (asp == NULL) {
223 			mutex_unlock(&authsvc_lock);
224 			return (-1);
225 		}
226 		asp->flavor = cred_flavor;
227 		asp->handler = handler;
228 		asp->next = Auths;
229 		Auths = asp;
230 		mutex_unlock(&authsvc_lock);
231 		break;
232 	}
233 	return (0);
234 }
235