xref: /netbsd-src/lib/libc/rpc/svc_auth.c (revision ba65fde2d7fefa7d39838fa5fa855e62bd606b5e)
1 /*	$NetBSD: svc_auth.c,v 1.16 2012/03/20 17:14:50 matt 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 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 #if 0
40 static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
41 #else
42 __RCSID("$NetBSD: svc_auth.c,v 1.16 2012/03/20 17:14:50 matt Exp $");
43 #endif
44 #endif
45 
46 /*
47  * svc_auth.c, Server-side rpc authenticator interface.
48  *
49  */
50 
51 #include "namespace.h"
52 #include "reentrant.h"
53 #include <sys/types.h>
54 #include <rpc/rpc.h>
55 #include <assert.h>
56 #include <stdlib.h>
57 
58 #ifdef __weak_alias
59 __weak_alias(svc_auth_reg,_svc_auth_reg)
60 #endif
61 
62 /*
63  * svcauthsw is the bdevsw of server side authentication.
64  *
65  * Server side authenticators are called from authenticate by
66  * using the client auth struct flavor field to index into svcauthsw.
67  * The server auth flavors must implement a routine that looks
68  * like:
69  *
70  *	enum auth_stat
71  *	flavorx_auth(rqst, msg)
72  *		struct svc_req *rqst;
73  *		struct rpc_msg *msg;
74  *
75  */
76 
77 /* declarations to allow servers to specify new authentication flavors */
78 struct authsvc {
79 	int	flavor;
80 	enum	auth_stat (*handler)(struct svc_req *, struct rpc_msg *);
81 	struct	authsvc	  *next;
82 };
83 static struct authsvc *Auths = NULL;
84 
85 /*
86  * The call rpc message, msg has been obtained from the wire.  The msg contains
87  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
88  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
89  * does the following things:
90  * set rqst->rq_xprt->verf to the appropriate response verifier;
91  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
92  *
93  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
94  * its length is set appropriately.
95  *
96  * The caller still owns and is responsible for msg->u.cmb.cred and
97  * msg->u.cmb.verf.  The authentication system retains ownership of
98  * rqst->rq_client_cred, the cooked credentials.
99  *
100  * There is an assumption that any flavour less than AUTH_NULL is
101  * invalid.
102  */
103 enum auth_stat
104 _authenticate(struct svc_req *rqst, struct rpc_msg *msg)
105 {
106 	int cred_flavor;
107 	struct authsvc *asp;
108 	enum auth_stat dummy;
109 #ifdef _REENTRANT
110 	extern mutex_t authsvc_lock;
111 #endif
112 
113 	_DIAGASSERT(rqst != NULL);
114 	_DIAGASSERT(msg != NULL);
115 
116 /* VARIABLES PROTECTED BY authsvc_lock: asp, Auths */
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 		dummy = _svcauth_null(rqst, msg);
125 		return (dummy);
126 	case AUTH_SYS:
127 		dummy = _svcauth_unix(rqst, msg);
128 		return (dummy);
129 	case AUTH_SHORT:
130 		dummy = _svcauth_short(rqst, msg);
131 		return (dummy);
132 #if 0
133 	case AUTH_DES:
134 		dummy = __svcauth_des(rqst, msg);
135 		return (dummy);
136 #endif
137 	default:
138 		break;
139 	}
140 
141 	/* flavor doesn't match any of the builtin types, so try new ones */
142 	mutex_lock(&authsvc_lock);
143 	for (asp = Auths; asp; asp = asp->next) {
144 		if (asp->flavor == cred_flavor) {
145 			enum auth_stat as;
146 
147 			as = (*asp->handler)(rqst, msg);
148 			mutex_unlock(&authsvc_lock);
149 			return (as);
150 		}
151 	}
152 	mutex_unlock(&authsvc_lock);
153 
154 	return (AUTH_REJECTEDCRED);
155 }
156 
157 /*ARGSUSED*/
158 enum auth_stat
159 _svcauth_null(struct svc_req *rqst, struct rpc_msg *msg)
160 {
161 	return (AUTH_OK);
162 }
163 
164 /*
165  *  Allow the rpc service to register new authentication types that it is
166  *  prepared to handle.  When an authentication flavor is registered,
167  *  the flavor is checked against already registered values.  If not
168  *  registered, then a new Auths entry is added on the list.
169  *
170  *  There is no provision to delete a registration once registered.
171  *
172  *  This routine returns:
173  *	 0 if registration successful
174  *	 1 if flavor already registered
175  *	-1 if can't register (errno set)
176  */
177 
178 int
179 svc_auth_reg(
180 	int cred_flavor,
181 	enum auth_stat (*handler)(struct svc_req *, struct rpc_msg *))
182 {
183 	struct authsvc *asp;
184 #ifdef _REENTRANT
185 	extern mutex_t authsvc_lock;
186 #endif
187 
188 	switch (cred_flavor) {
189 	    case AUTH_NULL:
190 	    case AUTH_SYS:
191 	    case AUTH_SHORT:
192 #if 0
193 	    case AUTH_DES:
194 #endif
195 		/* already registered */
196 		return (1);
197 
198 	    default:
199 		mutex_lock(&authsvc_lock);
200 		for (asp = Auths; asp; asp = asp->next) {
201 			if (asp->flavor == cred_flavor) {
202 				/* already registered */
203 				mutex_unlock(&authsvc_lock);
204 				return (1);
205 			}
206 		}
207 
208 		/* this is a new one, so go ahead and register it */
209 		asp = mem_alloc(sizeof (*asp));
210 		if (asp == NULL) {
211 			mutex_unlock(&authsvc_lock);
212 			return (-1);
213 		}
214 		asp->flavor = cred_flavor;
215 		asp->handler = handler;
216 		asp->next = Auths;
217 		Auths = asp;
218 		mutex_unlock(&authsvc_lock);
219 		break;
220 	}
221 	return (0);
222 }
223