svc_auth.c revision 55206 
1/*
2 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3 * unrestricted use provided that this legend is included on all tape
4 * media and as a part of the software program in whole or part.  Users
5 * may copy or modify Sun RPC without charge, but are not authorized
6 * to license or distribute it to anyone else except as part of a product or
7 * program developed by the user.
8 *
9 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12 *
13 * Sun RPC is provided with no support and without any obligation on the
14 * part of Sun Microsystems, Inc. to assist in its use, correction,
15 * modification or enhancement.
16 *
17 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19 * OR ANY PART THEREOF.
20 *
21 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22 * or profits or other special, indirect and consequential damages, even if
23 * Sun has been advised of the possibility of such damages.
24 *
25 * Sun Microsystems, Inc.
26 * 2550 Garcia Avenue
27 * Mountain View, California  94043
28 */
29/*
30 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
31 */
32
33#ident	"@(#)svc_auth.c	1.16	94/04/24 SMI"
34
35#if !defined(lint) && defined(SCCSIDS)
36#if 0
37static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
38#else
39static const char rcsid[] =
40 "$FreeBSD: head/lib/libc/rpc/svc_auth.c 55206 1999-12-29 05:07:58Z peter $";
41#endif
42#endif
43
44/*
45 * svc_auth.c, Server-side rpc authenticator interface.
46 *
47 */
48
49#ifdef _KERNEL
50#include <sys/param.h>
51#include <rpc/types.h>
52#include <rpc/xdr.h>
53#include <rpc/auth.h>
54#include <rpc/clnt.h>
55#include <rpc/rpc_msg.h>
56#include <rpc/svc.h>
57#include <rpc/svc_auth.h>
58#else
59#include <stdlib.h>
60#include <rpc/rpc.h>
61#endif
62#include <sys/types.h>
63
64/*
65 * svcauthsw is the bdevsw of server side authentication.
66 *
67 * Server side authenticators are called from authenticate by
68 * using the client auth struct flavor field to index into svcauthsw.
69 * The server auth flavors must implement a routine that looks
70 * like:
71 *
72 *	enum auth_stat
73 *	flavorx_auth(rqst, msg)
74 *		register struct svc_req *rqst;
75 *		register struct rpc_msg *msg;
76 *
77 */
78
79enum auth_stat _svcauth_null();	/* no authentication */
80enum auth_stat _svcauth_unix();		/* (system) unix style (uid, gids) */
81enum auth_stat _svcauth_short();	/* short hand unix style */
82enum auth_stat _svcauth_des();		/* des style */
83
84/* declarations to allow servers to specify new authentication flavors */
85struct authsvc {
86	int	flavor;
87	enum	auth_stat (*handler)();
88	struct	authsvc	  *next;
89};
90static struct authsvc *Auths = NULL;
91
92/*
93 * The call rpc message, msg has been obtained from the wire.  The msg contains
94 * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
95 * if the msg is successfully authenticated.  If AUTH_OK then the routine also
96 * does the following things:
97 * set rqst->rq_xprt->verf to the appropriate response verifier;
98 * sets rqst->rq_client_cred to the "cooked" form of the credentials.
99 *
100 * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
101 * its length is set appropriately.
102 *
103 * The caller still owns and is responsible for msg->u.cmb.cred and
104 * msg->u.cmb.verf.  The authentication system retains ownership of
105 * rqst->rq_client_cred, the cooked credentials.
106 *
107 * There is an assumption that any flavour less than AUTH_NULL is
108 * invalid.
109 */
110enum auth_stat
111_authenticate(rqst, msg)
112	register struct svc_req *rqst;
113	struct rpc_msg *msg;
114{
115	register int cred_flavor;
116	register struct authsvc *asp;
117
118	rqst->rq_cred = msg->rm_call.cb_cred;
119	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
120	rqst->rq_xprt->xp_verf.oa_length = 0;
121	cred_flavor = rqst->rq_cred.oa_flavor;
122	switch (cred_flavor) {
123	case AUTH_NULL:
124		return(_svcauth_null(rqst, msg));
125	case AUTH_UNIX:
126		return(_svcauth_unix(rqst, msg));
127	case AUTH_SHORT:
128		return(_svcauth_short(rqst, msg));
129	/*
130	 * We leave AUTH_DES turned off by default because svcauth_des()
131	 * needs getpublickey(), which is in librpcsvc, not libc. If we
132 	 * included AUTH_DES as a built-in flavor, programs that don't
133	 * have -lrpcsvc in their Makefiles wouldn't link correctly, even
134	 * though they don't use AUTH_DES. And I'm too lazy to go through
135	 * the tree looking for all of them.
136	 */
137#ifdef DES_BUILTIN
138	case AUTH_DES:
139		return(_svcauth_des(rqst, msg));
140#endif
141	}
142
143	/* flavor doesn't match any of the builtin types, so try new ones */
144	for (asp = Auths; asp; asp = asp->next) {
145		if (asp->flavor == cred_flavor) {
146			enum auth_stat as;
147
148			as = (*asp->handler)(rqst, msg);
149			return (as);
150		}
151	}
152
153	return (AUTH_REJECTEDCRED);
154}
155
156/*ARGSUSED*/
157enum auth_stat
158_svcauth_null(rqst, msg)
159	struct svc_req *rqst;
160	struct rpc_msg *msg;
161{
162	return (AUTH_OK);
163}
164
165/*
166 *  Allow the rpc service to register new authentication types that it is
167 *  prepared to handle.  When an authentication flavor is registered,
168 *  the flavor is checked against already registered values.  If not
169 *  registered, then a new Auths entry is added on the list.
170 *
171 *  There is no provision to delete a registration once registered.
172 *
173 *  This routine returns:
174 *	 0 if registration successful
175 *	 1 if flavor already registered
176 *	-1 if can't register (errno set)
177 */
178
179int
180svc_auth_reg(cred_flavor, handler)
181	register int cred_flavor;
182	enum auth_stat (*handler)();
183{
184	register struct authsvc *asp;
185
186	switch (cred_flavor) {
187	    case AUTH_NULL:
188	    case AUTH_UNIX:
189	    case AUTH_SHORT:
190#ifdef DES_BUILTIN
191	    case AUTH_DES:
192#endif
193		/* already registered */
194		return (1);
195
196	    default:
197		for (asp = Auths; asp; asp = asp->next) {
198			if (asp->flavor == cred_flavor) {
199				/* already registered */
200				return (1);
201			}
202		}
203
204		/* this is a new one, so go ahead and register it */
205		asp = (struct authsvc *)mem_alloc(sizeof (*asp));
206		if (asp == NULL) {
207			return (-1);
208		}
209		asp->flavor = cred_flavor;
210		asp->handler = handler;
211		asp->next = Auths;
212		Auths = asp;
213		break;
214	}
215	return (0);
216}
217