xref: /illumos-gate/usr/src/stand/lib/fs/nfs/auth_unix.c (revision b531f6d16eb39863e7bbc34773fb7ef7a282a0a2)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 /*
36  * Adapted for use by the boot program.
37  *
38  * auth_unix.c, Implements UNIX style authentication parameters.
39  *
40  * The system is very weak.  The client uses no encryption for its
41  * credentials and only sends null verifiers.  The server sends backs
42  * null verifiers or optionally a verifier that suggests a new short hand
43  * for the credentials.
44  */
45 
46 #include <stdlib.h>
47 #include <sys/sysmacros.h>
48 #include <rpc/types.h>
49 #include <rpc/xdr.h>
50 #include <rpc/auth.h>
51 #include "clnt.h"
52 #include <rpc/auth_unix.h>
53 #include <sys/promif.h>
54 #include <sys/salib.h>
55 #include <sys/bootdebug.h>
56 #include "nfs_inet.h"
57 
58 static struct auth_ops *authunix_ops();
59 /*
60  * This struct is pointed to by the ah_private field of an auth_handle.
61  */
62 struct audata {
63 	struct opaque_auth	au_origcred;	/* original credentials */
64 	struct opaque_auth	au_shcred;	/* short hand cred */
65 	uint_t			au_shfaults;	/* short hand cache faults */
66 	char			au_marshed[MAX_AUTH_BYTES];
67 	uint_t			au_mpos;	/* xdr pos at end of marshed */
68 };
69 #define	AUTH_PRIVATE(auth)	((struct audata *)auth->ah_private)
70 
71 static void marshal_new_auth(AUTH *);
72 
73 #define	dprintf	if (boothowto & RB_DEBUG) printf
74 
75 /*
76  * Create a unix style authenticator.
77  * Returns an auth handle with the given stuff in it.
78  */
79 AUTH *
authunix_create(char * machname,uid_t uid,gid_t gid,int len,gid_t * aup_gids)80 authunix_create(char *machname, uid_t uid, gid_t gid, int len, gid_t *aup_gids)
81 {
82 	struct authunix_parms aup;
83 	char mymem[MAX_AUTH_BYTES];
84 	XDR xdrs;
85 	AUTH *auth;
86 	struct audata *au;
87 
88 	/*
89 	 * Allocate and set up auth handle
90 	 */
91 	auth = (AUTH *) bkmem_alloc(sizeof (*auth));
92 	if (auth == NULL) {
93 		prom_panic("authunix_create: Cannot allocate memory.");
94 	}
95 
96 	au = (struct audata *)bkmem_alloc(sizeof (*au));
97 	if (au == NULL) {
98 		prom_panic("authunix_create: Cannot allocate memory.");
99 	}
100 
101 	/* setup authenticator. */
102 	auth->ah_ops = authunix_ops();
103 	auth->ah_private = (caddr_t)au;
104 
105 	/* structure copies */
106 	auth->ah_verf = au->au_shcred = _null_auth;
107 
108 	au->au_shfaults = 0;
109 
110 	/*
111 	 * fill in param struct from the given params
112 	 */
113 	aup.aup_time = prom_gettime() / 1000;
114 	aup.aup_machname = machname;
115 	aup.aup_uid = uid;
116 	aup.aup_gid = gid;
117 	aup.aup_len = (uint_t)len;
118 	aup.aup_gids = (gid_t *)aup_gids;
119 
120 	/*
121 	 * Serialize the parameters into origcred
122 	 */
123 	xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
124 	if (!xdr_authunix_parms(&xdrs, &aup)) {
125 		prom_panic("authunix_create:  xdr_authunix_parms failed");
126 	}
127 	au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
128 	au->au_origcred.oa_flavor = (uint_t)AUTH_UNIX;
129 	if ((au->au_origcred.oa_base = bkmem_alloc((uint_t)len)) == NULL) {
130 		prom_panic("authunix_create: memory alloc failed");
131 	}
132 	(void) bcopy(mymem, au->au_origcred.oa_base, (uint_t)len);
133 
134 	/*
135 	 * set auth handle to reflect new cred.
136 	 */
137 	auth->ah_cred = au->au_origcred;
138 	marshal_new_auth(auth);
139 	return (auth);
140 }
141 
142 /*
143  * authunix operations
144  */
145 
146 /* ARGSUSED */
147 static void
authunix_nextverf(AUTH * auth)148 authunix_nextverf(AUTH *auth)
149 {
150 }
151 
152 /* ARGSUSED */
153 static bool_t
authunix_marshal(AUTH * auth,XDR * xdrs,cred_t * cr)154 authunix_marshal(AUTH *auth, XDR *xdrs, cred_t *cr)
155 {
156 	struct audata *au = AUTH_PRIVATE(auth);
157 
158 	return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
159 }
160 
161 static bool_t
authunix_validate(AUTH * auth,struct opaque_auth * verf)162 authunix_validate(AUTH *auth, struct opaque_auth *verf)
163 {
164 	struct audata *au;
165 	XDR xdrs;
166 
167 	if (verf->oa_flavor == AUTH_SHORT) {
168 		au = AUTH_PRIVATE(auth);
169 
170 
171 		xdrmem_create(&xdrs, verf->oa_base, verf->oa_length,
172 		    XDR_DECODE);
173 
174 		if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
175 			auth->ah_cred = au->au_shcred;
176 		} else {
177 			xdrs.x_op = XDR_FREE;
178 			(void) xdr_opaque_auth(&xdrs, &au->au_shcred);
179 			au->au_shcred.oa_base = 0;
180 			auth->ah_cred = au->au_origcred;
181 		}
182 		marshal_new_auth(auth);
183 	}
184 
185 	return (TRUE);
186 }
187 
188 /*ARGSUSED*/
189 static bool_t
authunix_refresh(AUTH * auth,struct rpc_msg * msg,cred_t * cr)190 authunix_refresh(AUTH *auth, struct rpc_msg *msg, cred_t *cr)
191 {
192 	struct audata *au = AUTH_PRIVATE(auth);
193 	struct authunix_parms aup;
194 	XDR xdrs;
195 	int stat;
196 
197 	if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
198 		/* there is no hope.  Punt */
199 		return (FALSE);
200 	}
201 	au->au_shfaults ++;
202 
203 	/* first deserialize the creds back into a struct authunix_parms */
204 	aup.aup_machname = (char *)0;
205 	aup.aup_gids = (gid_t *)0;
206 	xdrmem_create(&xdrs, au->au_origcred.oa_base,
207 			au->au_origcred.oa_length, XDR_DECODE);
208 	stat = xdr_authunix_parms(&xdrs, &aup);
209 	if (!stat)
210 		goto done;
211 
212 	/* update the time and serialize in place */
213 	aup.aup_time = (prom_gettime() / 1000);
214 	xdrs.x_op = XDR_ENCODE;
215 	(void) XDR_SETPOS(&xdrs, 0);
216 	stat = xdr_authunix_parms(&xdrs, &aup);
217 	if (!stat)
218 		goto done;
219 	auth->ah_cred = au->au_origcred;
220 	marshal_new_auth(auth);
221 done:
222 	/* free the struct authunix_parms created by deserializing */
223 	xdrs.x_op = XDR_FREE;
224 	(void) xdr_authunix_parms(&xdrs, &aup);
225 	XDR_DESTROY(&xdrs);
226 	return (stat);
227 }
228 
229 static void
authunix_destroy(AUTH * auth)230 authunix_destroy(AUTH *auth)
231 {
232 	struct audata *au = AUTH_PRIVATE(auth);
233 
234 	if (au->au_shcred.oa_base != NULL)
235 		bkmem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
236 	bkmem_free(auth->ah_private, sizeof (struct audata));
237 	if (auth->ah_verf.oa_base != NULL)
238 		bkmem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
239 	bkmem_free((caddr_t)auth, sizeof (*auth));
240 }
241 
242 /*
243  * Marshals (pre-serializes) an auth struct.
244  * sets private data, au_marshed and au_mpos
245  */
246 static void
marshal_new_auth(AUTH * auth)247 marshal_new_auth(AUTH *auth)
248 {
249 	XDR xdr_stream;
250 	XDR *xdrs = &xdr_stream;
251 	struct audata *au = AUTH_PRIVATE(auth);
252 
253 	xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
254 	if ((!xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
255 	    (!xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
256 		dprintf("marshal_new_auth - Fatal marshalling problem");
257 	} else {
258 		au->au_mpos = XDR_GETPOS(xdrs);
259 	}
260 	XDR_DESTROY(xdrs);
261 }
262 
263 
264 static struct auth_ops *
authunix_ops(void)265 authunix_ops(void)
266 {
267 	static struct auth_ops ops;
268 
269 	if (ops.ah_nextverf == 0) {
270 		ops.ah_nextverf = authunix_nextverf;
271 		ops.ah_marshal = authunix_marshal;
272 		ops.ah_validate = authunix_validate;
273 		ops.ah_refresh = authunix_refresh;
274 		ops.ah_destroy = authunix_destroy;
275 	}
276 	return (&ops);
277 }
278 
279 /*
280  * XDR for unix authentication parameters.
281  */
282 bool_t
xdr_authunix_parms(XDR * xdrs,struct authunix_parms * p)283 xdr_authunix_parms(XDR *xdrs, struct authunix_parms *p)
284 {
285 	if (xdr_u_int(xdrs, &(p->aup_time)) &&
286 	    xdr_string(xdrs, &(p->aup_machname), MAX_MACHINE_NAME) &&
287 	    xdr_int(xdrs, (int *)&(p->aup_uid)) &&
288 	    xdr_int(xdrs, (int *)&(p->aup_gid)) &&
289 	    xdr_array(xdrs, (caddr_t *)&(p->aup_gids),
290 		    &(p->aup_len), NGRPS, sizeof (int), xdr_int)) {
291 		return (TRUE);
292 	}
293 	return (FALSE);
294 }
295