xref: /freebsd/lib/libc/rpc/svc_auth.c (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
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 /*
79  * The call rpc message, msg has been obtained from the wire.  The msg contains
80  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
81  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
82  * does the following things:
83  * set rqst->rq_xprt->verf to the appropriate response verifier;
84  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
85  *
86  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
87  * its length is set appropriately.
88  *
89  * The caller still owns and is responsible for msg->u.cmb.cred and
90  * msg->u.cmb.verf.  The authentication system retains ownership of
91  * rqst->rq_client_cred, the cooked credentials.
92  *
93  * There is an assumption that any flavour less than AUTH_NULL is
94  * invalid.
95  */
96 enum auth_stat
97 _authenticate(rqst, msg)
98 	struct svc_req *rqst;
99 	struct rpc_msg *msg;
100 {
101 	int cred_flavor;
102 	struct authsvc *asp;
103 	enum auth_stat dummy;
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*/
147 enum 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 
169 int
170 svc_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 
176 	switch (cred_flavor) {
177 	    case AUTH_NULL:
178 	    case AUTH_SYS:
179 	    case AUTH_SHORT:
180 #ifdef DES_BUILTIN
181 	    case AUTH_DES:
182 #endif
183 		/* already registered */
184 		return (1);
185 
186 	    default:
187 		mutex_lock(&authsvc_lock);
188 		for (asp = Auths; asp; asp = asp->next) {
189 			if (asp->flavor == cred_flavor) {
190 				/* already registered */
191 				mutex_unlock(&authsvc_lock);
192 				return (1);
193 			}
194 		}
195 
196 		/* this is a new one, so go ahead and register it */
197 		asp = mem_alloc(sizeof (*asp));
198 		if (asp == NULL) {
199 			mutex_unlock(&authsvc_lock);
200 			return (-1);
201 		}
202 		asp->flavor = cred_flavor;
203 		asp->handler = handler;
204 		asp->next = Auths;
205 		Auths = asp;
206 		mutex_unlock(&authsvc_lock);
207 		break;
208 	}
209 	return (0);
210 }
211