svc_auth.c revision 136581 
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"
37static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
38#endif
39#include <sys/cdefs.h>
40__FBSDID("$FreeBSD: head/lib/libc/rpc/svc_auth.c 136581 2004-10-16 06:11:35Z obrien $");
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
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
77/*
78 * The call rpc message, msg has been obtained from the wire.  The msg contains
79 * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
80 * if the msg is successfully authenticated.  If AUTH_OK then the routine also
81 * does the following things:
82 * set rqst->rq_xprt->verf to the appropriate response verifier;
83 * sets rqst->rq_client_cred to the "cooked" form of the credentials.
84 *
85 * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
86 * its length is set appropriately.
87 *
88 * The caller still owns and is responsible for msg->u.cmb.cred and
89 * msg->u.cmb.verf.  The authentication system retains ownership of
90 * rqst->rq_client_cred, the cooked credentials.
91 *
92 * There is an assumption that any flavour less than AUTH_NULL is
93 * invalid.
94 */
95enum auth_stat
96_authenticate(rqst, msg)
97	struct svc_req *rqst;
98	struct rpc_msg *msg;
99{
100	int cred_flavor;
101	struct authsvc *asp;
102	enum auth_stat dummy;
103	extern mutex_t authsvc_lock;
104
105/* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
106
107	rqst->rq_cred = msg->rm_call.cb_cred;
108	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
109	rqst->rq_xprt->xp_verf.oa_length = 0;
110	cred_flavor = rqst->rq_cred.oa_flavor;
111	switch (cred_flavor) {
112	case AUTH_NULL:
113		dummy = _svcauth_null(rqst, msg);
114		return (dummy);
115	case AUTH_SYS:
116		dummy = _svcauth_unix(rqst, msg);
117		return (dummy);
118	case AUTH_SHORT:
119		dummy = _svcauth_short(rqst, msg);
120		return (dummy);
121#ifdef DES_BUILTIN
122	case AUTH_DES:
123		dummy = _svcauth_des(rqst, msg);
124		return (dummy);
125#endif
126	default:
127		break;
128	}
129
130	/* flavor doesn't match any of the builtin types, so try new ones */
131	mutex_lock(&authsvc_lock);
132	for (asp = Auths; asp; asp = asp->next) {
133		if (asp->flavor == cred_flavor) {
134			enum auth_stat as;
135
136			as = (*asp->handler)(rqst, msg);
137			mutex_unlock(&authsvc_lock);
138			return (as);
139		}
140	}
141	mutex_unlock(&authsvc_lock);
142
143	return (AUTH_REJECTEDCRED);
144}
145
146/*ARGSUSED*/
147enum auth_stat
148_svcauth_null(rqst, msg)
149	struct svc_req *rqst;
150	struct rpc_msg *msg;
151{
152	return (AUTH_OK);
153}
154
155/*
156 *  Allow the rpc service to register new authentication types that it is
157 *  prepared to handle.  When an authentication flavor is registered,
158 *  the flavor is checked against already registered values.  If not
159 *  registered, then a new Auths entry is added on the list.
160 *
161 *  There is no provision to delete a registration once registered.
162 *
163 *  This routine returns:
164 *	 0 if registration successful
165 *	 1 if flavor already registered
166 *	-1 if can't register (errno set)
167 */
168
169int
170svc_auth_reg(cred_flavor, handler)
171	int cred_flavor;
172	enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
173{
174	struct authsvc *asp;
175	extern mutex_t authsvc_lock;
176
177	switch (cred_flavor) {
178	    case AUTH_NULL:
179	    case AUTH_SYS:
180	    case AUTH_SHORT:
181#ifdef DES_BUILTIN
182	    case AUTH_DES:
183#endif
184		/* already registered */
185		return (1);
186
187	    default:
188		mutex_lock(&authsvc_lock);
189		for (asp = Auths; asp; asp = asp->next) {
190			if (asp->flavor == cred_flavor) {
191				/* already registered */
192				mutex_unlock(&authsvc_lock);
193				return (1);
194			}
195		}
196
197		/* this is a new one, so go ahead and register it */
198		asp = mem_alloc(sizeof (*asp));
199		if (asp == NULL) {
200			mutex_unlock(&authsvc_lock);
201			return (-1);
202		}
203		asp->flavor = cred_flavor;
204		asp->handler = handler;
205		asp->next = Auths;
206		Auths = asp;
207		mutex_unlock(&authsvc_lock);
208		break;
209	}
210	return (0);
211}
212