xref: /dragonfly/lib/libc/rpc/svc_auth.c (revision 984263bc)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  */
29 /*
30  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
31  */
32 
33 #ident	"@(#)svc_auth.c	1.16	94/04/24 SMI"
34 
35 #if !defined(lint) && defined(SCCSIDS)
36 #if 0
37 static char sccsid[] = "@(#)svc_auth.c 1.26 89/02/07 Copyr 1984 Sun Micro";
38 #else
39 static const char rcsid[] =
40  "$FreeBSD: src/lib/libc/rpc/svc_auth.c,v 1.7 1999/12/29 05:04:16 peter Exp $";
41 #endif
42 #endif
43 
44 /*
45  * svc_auth.c, Server-side rpc authenticator interface.
46  *
47  */
48 
49 #ifdef _KERNEL
50 #include <sys/param.h>
51 #include <rpc/types.h>
52 #include <rpc/xdr.h>
53 #include <rpc/auth.h>
54 #include <rpc/clnt.h>
55 #include <rpc/rpc_msg.h>
56 #include <rpc/svc.h>
57 #include <rpc/svc_auth.h>
58 #else
59 #include <stdlib.h>
60 #include <rpc/rpc.h>
61 #endif
62 #include <sys/types.h>
63 
64 /*
65  * svcauthsw is the bdevsw of server side authentication.
66  *
67  * Server side authenticators are called from authenticate by
68  * using the client auth struct flavor field to index into svcauthsw.
69  * The server auth flavors must implement a routine that looks
70  * like:
71  *
72  *	enum auth_stat
73  *	flavorx_auth(rqst, msg)
74  *		register struct svc_req *rqst;
75  *		register struct rpc_msg *msg;
76  *
77  */
78 
79 enum auth_stat _svcauth_null();	/* no authentication */
80 enum auth_stat _svcauth_unix();		/* (system) unix style (uid, gids) */
81 enum auth_stat _svcauth_short();	/* short hand unix style */
82 enum auth_stat _svcauth_des();		/* des style */
83 
84 /* declarations to allow servers to specify new authentication flavors */
85 struct authsvc {
86 	int	flavor;
87 	enum	auth_stat (*handler)();
88 	struct	authsvc	  *next;
89 };
90 static struct authsvc *Auths = NULL;
91 
92 /*
93  * The call rpc message, msg has been obtained from the wire.  The msg contains
94  * the raw form of credentials and verifiers.  authenticate returns AUTH_OK
95  * if the msg is successfully authenticated.  If AUTH_OK then the routine also
96  * does the following things:
97  * set rqst->rq_xprt->verf to the appropriate response verifier;
98  * sets rqst->rq_client_cred to the "cooked" form of the credentials.
99  *
100  * NB: rqst->rq_cxprt->verf must be pre-alloctaed;
101  * its length is set appropriately.
102  *
103  * The caller still owns and is responsible for msg->u.cmb.cred and
104  * msg->u.cmb.verf.  The authentication system retains ownership of
105  * rqst->rq_client_cred, the cooked credentials.
106  *
107  * There is an assumption that any flavour less than AUTH_NULL is
108  * invalid.
109  */
110 enum auth_stat
111 _authenticate(rqst, msg)
112 	register struct svc_req *rqst;
113 	struct rpc_msg *msg;
114 {
115 	register int cred_flavor;
116 	register struct authsvc *asp;
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 		return(_svcauth_null(rqst, msg));
125 	case AUTH_UNIX:
126 		return(_svcauth_unix(rqst, msg));
127 	case AUTH_SHORT:
128 		return(_svcauth_short(rqst, msg));
129 	/*
130 	 * We leave AUTH_DES turned off by default because svcauth_des()
131 	 * needs getpublickey(), which is in librpcsvc, not libc. If we
132  	 * included AUTH_DES as a built-in flavor, programs that don't
133 	 * have -lrpcsvc in their Makefiles wouldn't link correctly, even
134 	 * though they don't use AUTH_DES. And I'm too lazy to go through
135 	 * the tree looking for all of them.
136 	 */
137 #ifdef DES_BUILTIN
138 	case AUTH_DES:
139 		return(_svcauth_des(rqst, msg));
140 #endif
141 	}
142 
143 	/* flavor doesn't match any of the builtin types, so try new ones */
144 	for (asp = Auths; asp; asp = asp->next) {
145 		if (asp->flavor == cred_flavor) {
146 			enum auth_stat as;
147 
148 			as = (*asp->handler)(rqst, msg);
149 			return (as);
150 		}
151 	}
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 	register int cred_flavor;
182 	enum auth_stat (*handler)();
183 {
184 	register struct authsvc *asp;
185 
186 	switch (cred_flavor) {
187 	    case AUTH_NULL:
188 	    case AUTH_UNIX:
189 	    case AUTH_SHORT:
190 #ifdef DES_BUILTIN
191 	    case AUTH_DES:
192 #endif
193 		/* already registered */
194 		return (1);
195 
196 	    default:
197 		for (asp = Auths; asp; asp = asp->next) {
198 			if (asp->flavor == cred_flavor) {
199 				/* already registered */
200 				return (1);
201 			}
202 		}
203 
204 		/* this is a new one, so go ahead and register it */
205 		asp = (struct authsvc *)mem_alloc(sizeof (*asp));
206 		if (asp == NULL) {
207 			return (-1);
208 		}
209 		asp->flavor = cred_flavor;
210 		asp->handler = handler;
211 		asp->next = Auths;
212 		Auths = asp;
213 		break;
214 	}
215 	return (0);
216 }
217