1 /* $NetBSD: auth_unix.c,v 1.18 2000/07/06 03:03:30 christos Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (c) 2009, Sun Microsystems, Inc.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
11 * - Redistributions of source code must retain the above copyright notice,
12 * this list of conditions and the following disclaimer.
13 * - Redistributions in binary form must reproduce the above copyright notice,
14 * this list of conditions and the following disclaimer in the documentation
15 * and/or other materials provided with the distribution.
16 * - Neither the name of Sun Microsystems, Inc. nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #if defined(LIBC_SCCS) && !defined(lint)
34 static char *sccsid2 = "@(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro";
35 static char *sccsid = "@(#)auth_unix.c 2.2 88/08/01 4.0 RPCSRC";
36 #endif
37 /*
38 * auth_unix.c, Implements UNIX style authentication parameters.
39 *
40 * Copyright (C) 1984, Sun Microsystems, Inc.
41 *
42 * The system is very weak. The client uses no encryption for it's
43 * credentials and only sends null verifiers. The server sends backs
44 * null verifiers or optionally a verifier that suggests a new short hand
45 * for the credentials.
46 *
47 */
48
49 #include "namespace.h"
50 #include "reentrant.h"
51 #include <sys/param.h>
52
53 #include <assert.h>
54 #include <err.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <unistd.h>
58 #include <string.h>
59
60 #include <rpc/types.h>
61 #include <rpc/xdr.h>
62 #include <rpc/auth.h>
63 #include <rpc/auth_unix.h>
64 #include "un-namespace.h"
65 #include "mt_misc.h"
66
67 /* auth_unix.c */
68 static void authunix_nextverf (AUTH *);
69 static bool_t authunix_marshal (AUTH *, XDR *);
70 static bool_t authunix_validate (AUTH *, struct opaque_auth *);
71 static bool_t authunix_refresh (AUTH *, void *);
72 static void authunix_destroy (AUTH *);
73 static void marshal_new_auth (AUTH *);
74 static struct auth_ops *authunix_ops (void);
75
76 /*
77 * This struct is pointed to by the ah_private field of an auth_handle.
78 */
79 struct audata {
80 struct opaque_auth au_origcred; /* original credentials */
81 struct opaque_auth au_shcred; /* short hand cred */
82 u_long au_shfaults; /* short hand cache faults */
83 char au_marshed[MAX_AUTH_BYTES];
84 u_int au_mpos; /* xdr pos at end of marshed */
85 };
86 #define AUTH_PRIVATE(auth) ((struct audata *)auth->ah_private)
87
88 /*
89 * Create a unix style authenticator.
90 * Returns an auth handle with the given stuff in it.
91 */
92 AUTH *
authunix_create(char * machname,u_int uid,u_int gid,int len,u_int * aup_gids)93 authunix_create(char *machname, u_int uid, u_int gid, int len, u_int *aup_gids)
94 {
95 struct authunix_parms aup;
96 char mymem[MAX_AUTH_BYTES];
97 struct timeval now;
98 XDR xdrs;
99 AUTH *auth;
100 struct audata *au;
101
102 /*
103 * Allocate and set up auth handle
104 */
105 au = NULL;
106 auth = mem_alloc(sizeof(*auth));
107 #ifndef _KERNEL
108 if (auth == NULL) {
109 warnx("authunix_create: out of memory");
110 goto cleanup_authunix_create;
111 }
112 #endif
113 au = mem_alloc(sizeof(*au));
114 #ifndef _KERNEL
115 if (au == NULL) {
116 warnx("authunix_create: out of memory");
117 goto cleanup_authunix_create;
118 }
119 #endif
120 auth->ah_ops = authunix_ops();
121 auth->ah_private = (caddr_t)au;
122 auth->ah_verf = au->au_shcred = _null_auth;
123 au->au_shfaults = 0;
124 au->au_origcred.oa_base = NULL;
125
126 /*
127 * fill in param struct from the given params
128 */
129 (void)gettimeofday(&now, NULL);
130 aup.aup_time = now.tv_sec;
131 aup.aup_machname = machname;
132 aup.aup_uid = uid;
133 aup.aup_gid = gid;
134 aup.aup_len = (u_int)len;
135 aup.aup_gids = aup_gids;
136
137 /*
138 * Serialize the parameters into origcred
139 */
140 xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
141 if (! xdr_authunix_parms(&xdrs, &aup))
142 abort();
143 au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
144 au->au_origcred.oa_flavor = AUTH_UNIX;
145 #ifdef _KERNEL
146 au->au_origcred.oa_base = mem_alloc((u_int) len);
147 #else
148 if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
149 warnx("authunix_create: out of memory");
150 goto cleanup_authunix_create;
151 }
152 #endif
153 memmove(au->au_origcred.oa_base, mymem, (size_t)len);
154
155 /*
156 * set auth handle to reflect new cred.
157 */
158 auth->ah_cred = au->au_origcred;
159 marshal_new_auth(auth);
160 return (auth);
161 #ifndef _KERNEL
162 cleanup_authunix_create:
163 if (auth)
164 mem_free(auth, sizeof(*auth));
165 if (au) {
166 if (au->au_origcred.oa_base)
167 mem_free(au->au_origcred.oa_base, (u_int)len);
168 mem_free(au, sizeof(*au));
169 }
170 return (NULL);
171 #endif
172 }
173
174 /*
175 * Returns an auth handle with parameters determined by doing lots of
176 * syscalls.
177 */
178 AUTH *
authunix_create_default(void)179 authunix_create_default(void)
180 {
181 AUTH *auth;
182 int ngids;
183 long ngids_max;
184 char machname[MAXHOSTNAMELEN + 1];
185 uid_t uid;
186 gid_t gid;
187 gid_t *gids;
188
189 ngids_max = sysconf(_SC_NGROUPS_MAX) + 1;
190 gids = malloc(sizeof(gid_t) * ngids_max);
191 if (gids == NULL)
192 return (NULL);
193
194 if (gethostname(machname, sizeof machname) == -1)
195 abort();
196 machname[sizeof(machname) - 1] = 0;
197 uid = geteuid();
198 gid = getegid();
199 if ((ngids = getgroups(ngids_max, gids)) < 0)
200 abort();
201 if (ngids > NGRPS)
202 ngids = NGRPS;
203 /* XXX: interface problem; we should translate from uid_t and gid_t */
204 auth = authunix_create(machname, uid, gid, ngids, gids);
205 free(gids);
206 return (auth);
207 }
208
209 /*
210 * authunix operations
211 */
212
213 /* ARGSUSED */
214 static void
authunix_nextverf(AUTH * auth)215 authunix_nextverf(AUTH *auth)
216 {
217 /* no action necessary */
218 }
219
220 static bool_t
authunix_marshal(AUTH * auth,XDR * xdrs)221 authunix_marshal(AUTH *auth, XDR *xdrs)
222 {
223 struct audata *au;
224
225 assert(auth != NULL);
226 assert(xdrs != NULL);
227
228 au = AUTH_PRIVATE(auth);
229 return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
230 }
231
232 static bool_t
authunix_validate(AUTH * auth,struct opaque_auth * verf)233 authunix_validate(AUTH *auth, struct opaque_auth *verf)
234 {
235 struct audata *au;
236 XDR xdrs;
237
238 assert(auth != NULL);
239 assert(verf != NULL);
240
241 if (verf->oa_flavor == AUTH_SHORT) {
242 au = AUTH_PRIVATE(auth);
243 xdrmem_create(&xdrs, verf->oa_base, verf->oa_length,
244 XDR_DECODE);
245
246 if (au->au_shcred.oa_base != NULL) {
247 mem_free(au->au_shcred.oa_base,
248 au->au_shcred.oa_length);
249 au->au_shcred.oa_base = NULL;
250 }
251 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
252 auth->ah_cred = au->au_shcred;
253 } else {
254 xdrs.x_op = XDR_FREE;
255 (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
256 au->au_shcred.oa_base = NULL;
257 auth->ah_cred = au->au_origcred;
258 }
259 marshal_new_auth(auth);
260 }
261 return (TRUE);
262 }
263
264 static bool_t
authunix_refresh(AUTH * auth,void * dummy)265 authunix_refresh(AUTH *auth, void *dummy)
266 {
267 struct audata *au = AUTH_PRIVATE(auth);
268 struct authunix_parms aup;
269 struct timeval now;
270 XDR xdrs;
271 int stat;
272
273 assert(auth != NULL);
274
275 if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
276 /* there is no hope. Punt */
277 return (FALSE);
278 }
279 au->au_shfaults ++;
280
281 /* first deserialize the creds back into a struct authunix_parms */
282 aup.aup_machname = NULL;
283 aup.aup_gids = NULL;
284 xdrmem_create(&xdrs, au->au_origcred.oa_base,
285 au->au_origcred.oa_length, XDR_DECODE);
286 stat = xdr_authunix_parms(&xdrs, &aup);
287 if (! stat)
288 goto done;
289
290 /* update the time and serialize in place */
291 (void)gettimeofday(&now, NULL);
292 aup.aup_time = now.tv_sec;
293 xdrs.x_op = XDR_ENCODE;
294 XDR_SETPOS(&xdrs, 0);
295 stat = xdr_authunix_parms(&xdrs, &aup);
296 if (! stat)
297 goto done;
298 auth->ah_cred = au->au_origcred;
299 marshal_new_auth(auth);
300 done:
301 /* free the struct authunix_parms created by deserializing */
302 xdrs.x_op = XDR_FREE;
303 (void)xdr_authunix_parms(&xdrs, &aup);
304 XDR_DESTROY(&xdrs);
305 return (stat);
306 }
307
308 static void
authunix_destroy(AUTH * auth)309 authunix_destroy(AUTH *auth)
310 {
311 struct audata *au;
312
313 assert(auth != NULL);
314
315 au = AUTH_PRIVATE(auth);
316 mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
317
318 if (au->au_shcred.oa_base != NULL)
319 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
320
321 mem_free(auth->ah_private, sizeof(struct audata));
322
323 if (auth->ah_verf.oa_base != NULL)
324 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
325
326 mem_free(auth, sizeof(*auth));
327 }
328
329 /*
330 * Marshals (pre-serializes) an auth struct.
331 * sets private data, au_marshed and au_mpos
332 */
333 static void
marshal_new_auth(AUTH * auth)334 marshal_new_auth(AUTH *auth)
335 {
336 XDR xdr_stream;
337 XDR *xdrs = &xdr_stream;
338 struct audata *au;
339
340 assert(auth != NULL);
341
342 au = AUTH_PRIVATE(auth);
343 xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
344 if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
345 (! xdr_opaque_auth(xdrs, &(auth->ah_verf))))
346 warnx("auth_none.c - Fatal marshalling problem");
347 else
348 au->au_mpos = XDR_GETPOS(xdrs);
349 XDR_DESTROY(xdrs);
350 }
351
352 static struct auth_ops *
authunix_ops(void)353 authunix_ops(void)
354 {
355 static struct auth_ops ops;
356
357 /* VARIABLES PROTECTED BY ops_lock: ops */
358
359 mutex_lock(&ops_lock);
360 if (ops.ah_nextverf == NULL) {
361 ops.ah_nextverf = authunix_nextverf;
362 ops.ah_marshal = authunix_marshal;
363 ops.ah_validate = authunix_validate;
364 ops.ah_refresh = authunix_refresh;
365 ops.ah_destroy = authunix_destroy;
366 }
367 mutex_unlock(&ops_lock);
368 return (&ops);
369 }
370