xref: /netbsd-src/lib/libc/rpc/svc_auth.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: svc_auth.c,v 1.13 2001/01/04 14:42:21 lukem 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 #endif
41 #endif
42 
43 /*
44  * svc_auth.c, Server-side rpc authenticator interface.
45  *
46  */
47 
48 #include "namespace.h"
49 #include "reentrant.h"
50 #include <sys/types.h>
51 #include <rpc/rpc.h>
52 #include <assert.h>
53 #include <stdlib.h>
54 
55 #ifdef __weak_alias
56 __weak_alias(svc_auth_reg,_svc_auth_reg)
57 #endif
58 
59 /*
60  * svcauthsw is the bdevsw of server side authentication.
61  *
62  * Server side authenticators are called from authenticate by
63  * using the client auth struct flavor field to index into svcauthsw.
64  * The server auth flavors must implement a routine that looks
65  * like:
66  *
67  *	enum auth_stat
68  *	flavorx_auth(rqst, msg)
69  *		struct svc_req *rqst;
70  *		struct rpc_msg *msg;
71  *
72  */
73 
74 /* declarations to allow servers to specify new authentication flavors */
75 struct authsvc {
76 	int	flavor;
77 	enum	auth_stat (*handler) __P((struct svc_req *, struct rpc_msg *));
78 	struct	authsvc	  *next;
79 };
80 static struct authsvc *Auths = NULL;
81 
82 /*
83  * The call rpc message, msg has been obtained from the wire.  The msg contains
84  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
85  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
86  * does the following things:
87  * set rqst->rq_xprt->verf to the appropriate response verifier;
88  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
89  *
90  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
91  * its length is set appropriately.
92  *
93  * The caller still owns and is responsible for msg->u.cmb.cred and
94  * msg->u.cmb.verf.  The authentication system retains ownership of
95  * rqst->rq_client_cred, the cooked credentials.
96  *
97  * There is an assumption that any flavour less than AUTH_NULL is
98  * invalid.
99  */
100 enum auth_stat
101 _authenticate(rqst, msg)
102 	struct svc_req *rqst;
103 	struct rpc_msg *msg;
104 {
105 	int cred_flavor;
106 	struct authsvc *asp;
107 	enum auth_stat dummy;
108 #ifdef __REENT
109 	extern mutex_t authsvc_lock;
110 #endif
111 
112 	_DIAGASSERT(rqst != NULL);
113 	_DIAGASSERT(msg != NULL);
114 
115 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
116 
117 	rqst->rq_cred = msg->rm_call.cb_cred;
118 	rqst->rq_xprt->xp_verf.oa_flavor = _null_auth.oa_flavor;
119 	rqst->rq_xprt->xp_verf.oa_length = 0;
120 	cred_flavor = rqst->rq_cred.oa_flavor;
121 	switch (cred_flavor) {
122 	case AUTH_NULL:
123 		dummy = _svcauth_null(rqst, msg);
124 		return (dummy);
125 	case AUTH_SYS:
126 		dummy = _svcauth_unix(rqst, msg);
127 		return (dummy);
128 	case AUTH_SHORT:
129 		dummy = _svcauth_short(rqst, msg);
130 		return (dummy);
131 #if 0
132 	case AUTH_DES:
133 		dummy = __svcauth_des(rqst, msg);
134 		return (dummy);
135 #endif
136 	default:
137 		break;
138 	}
139 
140 	/* flavor doesn't match any of the builtin types, so try new ones */
141 	mutex_lock(&authsvc_lock);
142 	for (asp = Auths; asp; asp = asp->next) {
143 		if (asp->flavor == cred_flavor) {
144 			enum auth_stat as;
145 
146 			as = (*asp->handler)(rqst, msg);
147 			mutex_unlock(&authsvc_lock);
148 			return (as);
149 		}
150 	}
151 	mutex_unlock(&authsvc_lock);
152 
153 	return (AUTH_REJECTEDCRED);
154 }
155 
156 /*ARGSUSED*/
157 enum 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 
179 int
180 svc_auth_reg(cred_flavor, handler)
181 	int cred_flavor;
182 	enum auth_stat (*handler) __P((struct svc_req *, struct rpc_msg *));
183 {
184 	struct authsvc *asp;
185 #ifdef __REENT
186 	extern mutex_t authsvc_lock;
187 #endif
188 
189 	switch (cred_flavor) {
190 	    case AUTH_NULL:
191 	    case AUTH_SYS:
192 	    case AUTH_SHORT:
193 #if 0
194 	    case AUTH_DES:
195 #endif
196 		/* already registered */
197 		return (1);
198 
199 	    default:
200 		mutex_lock(&authsvc_lock);
201 		for (asp = Auths; asp; asp = asp->next) {
202 			if (asp->flavor == cred_flavor) {
203 				/* already registered */
204 				mutex_unlock(&authsvc_lock);
205 				return (1);
206 			}
207 		}
208 
209 		/* this is a new one, so go ahead and register it */
210 		asp = mem_alloc(sizeof (*asp));
211 		if (asp == NULL) {
212 			mutex_unlock(&authsvc_lock);
213 			return (-1);
214 		}
215 		asp->flavor = cred_flavor;
216 		asp->handler = handler;
217 		asp->next = Auths;
218 		Auths = asp;
219 		mutex_unlock(&authsvc_lock);
220 		break;
221 	}
222 	return (0);
223 }
224