xref: /freebsd/lib/libc/rpc/svc_auth.c (revision 5521ff5a4d1929056e7ffc982fac3341ca54df7c)
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 /* #ident	"@(#)svc_auth.c	1.16	94/04/24 SMI" */
36 
37 #if 0
38 #if !defined(lint) && defined(SCCSIDS)
39 static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
40 static const char rcsid[] = "$FreeBSD$";
41 #endif
42 #endif
43 
44 /*
45  * svc_auth.c, Server-side rpc authenticator interface.
46  *
47  */
48 
49 #include "namespace.h"
50 #include "reentrant.h"
51 #include <sys/types.h>
52 #include <rpc/rpc.h>
53 #include <stdlib.h>
54 #include "un-namespace.h"
55 
56 /*
57  * svcauthsw is the bdevsw of server side authentication.
58  *
59  * Server side authenticators are called from authenticate by
60  * using the client auth struct flavor field to index into svcauthsw.
61  * The server auth flavors must implement a routine that looks
62  * like:
63  *
64  *	enum auth_stat
65  *	flavorx_auth(rqst, msg)
66  *		struct svc_req *rqst;
67  *		struct rpc_msg *msg;
68  *
69  */
70 
71 /* declarations to allow servers to specify new authentication flavors */
72 struct authsvc {
73 	int	flavor;
74 	enum	auth_stat (*handler) __P((struct svc_req *, struct rpc_msg *));
75 	struct	authsvc	  *next;
76 };
77 static struct authsvc *Auths = NULL;
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 	extern mutex_t authsvc_lock;
106 
107 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
108 
109 	rqst->rq_cred = msg->rm_call.cb_cred;
110 	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
111 	rqst->rq_xprt->xp_verf.oa_length = 0;
112 	cred_flavor = rqst->rq_cred.oa_flavor;
113 	switch (cred_flavor) {
114 	case AUTH_NULL:
115 		dummy = _svcauth_null(rqst, msg);
116 		return (dummy);
117 	case AUTH_SYS:
118 		dummy = _svcauth_unix(rqst, msg);
119 		return (dummy);
120 	case AUTH_SHORT:
121 		dummy = _svcauth_short(rqst, msg);
122 		return (dummy);
123 #ifdef DES_BUILTIN
124 	case AUTH_DES:
125 		dummy = _svcauth_des(rqst, msg);
126 		return (dummy);
127 #endif
128 	default:
129 		break;
130 	}
131 
132 	/* flavor doesn't match any of the builtin types, so try new ones */
133 	mutex_lock(&authsvc_lock);
134 	for (asp = Auths; asp; asp = asp->next) {
135 		if (asp->flavor == cred_flavor) {
136 			enum auth_stat as;
137 
138 			as = (*asp->handler)(rqst, msg);
139 			mutex_unlock(&authsvc_lock);
140 			return (as);
141 		}
142 	}
143 	mutex_unlock(&authsvc_lock);
144 
145 	return (AUTH_REJECTEDCRED);
146 }
147 
148 /*ARGSUSED*/
149 enum auth_stat
150 _svcauth_null(rqst, msg)
151 	struct svc_req *rqst;
152 	struct rpc_msg *msg;
153 {
154 	return (AUTH_OK);
155 }
156 
157 /*
158  *  Allow the rpc service to register new authentication types that it is
159  *  prepared to handle.  When an authentication flavor is registered,
160  *  the flavor is checked against already registered values.  If not
161  *  registered, then a new Auths entry is added on the list.
162  *
163  *  There is no provision to delete a registration once registered.
164  *
165  *  This routine returns:
166  *	 0 if registration successful
167  *	 1 if flavor already registered
168  *	-1 if can't register (errno set)
169  */
170 
171 int
172 svc_auth_reg(cred_flavor, handler)
173 	int cred_flavor;
174 	enum auth_stat (*handler) __P((struct svc_req *, struct rpc_msg *));
175 {
176 	struct authsvc *asp;
177 	extern mutex_t authsvc_lock;
178 
179 	switch (cred_flavor) {
180 	    case AUTH_NULL:
181 	    case AUTH_SYS:
182 	    case AUTH_SHORT:
183 #ifdef DES_BUILTIN
184 	    case AUTH_DES:
185 #endif
186 		/* already registered */
187 		return (1);
188 
189 	    default:
190 		mutex_lock(&authsvc_lock);
191 		for (asp = Auths; asp; asp = asp->next) {
192 			if (asp->flavor == cred_flavor) {
193 				/* already registered */
194 				mutex_unlock(&authsvc_lock);
195 				return (1);
196 			}
197 		}
198 
199 		/* this is a new one, so go ahead and register it */
200 		asp = mem_alloc(sizeof (*asp));
201 		if (asp == NULL) {
202 			mutex_unlock(&authsvc_lock);
203 			return (-1);
204 		}
205 		asp->flavor = cred_flavor;
206 		asp->handler = handler;
207 		asp->next = Auths;
208 		Auths = asp;
209 		mutex_unlock(&authsvc_lock);
210 		break;
211 	}
212 	return (0);
213 }
214