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 /*
34 * auth_unix.c, Implements UNIX style authentication parameters.
35 *
36 * Copyright (C) 1984, Sun Microsystems, Inc.
37 *
38 * The system is very weak. The client uses no encryption for it's
39 * credentials and only sends null verifiers. The server sends backs
40 * null verifiers or optionally a verifier that suggests a new short hand
41 * for the credentials.
42 *
43 */
44
45 #include "namespace.h"
46 #include "reentrant.h"
47 #include <sys/param.h>
48
49 #include <assert.h>
50 #include <err.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <unistd.h>
54 #include <string.h>
55
56 #include <rpc/types.h>
57 #include <rpc/xdr.h>
58 #include <rpc/auth.h>
59 #include <rpc/auth_unix.h>
60 #include "un-namespace.h"
61 #include "mt_misc.h"
62
63 /* auth_unix.c */
64 static void authunix_nextverf (AUTH *);
65 static bool_t authunix_marshal (AUTH *, XDR *);
66 static bool_t authunix_validate (AUTH *, struct opaque_auth *);
67 static bool_t authunix_refresh (AUTH *, void *);
68 static void authunix_destroy (AUTH *);
69 static void marshal_new_auth (AUTH *);
70 static struct auth_ops *authunix_ops (void);
71
72 /*
73 * This struct is pointed to by the ah_private field of an auth_handle.
74 */
75 struct audata {
76 struct opaque_auth au_origcred; /* original credentials */
77 struct opaque_auth au_shcred; /* short hand cred */
78 u_long au_shfaults; /* short hand cache faults */
79 char au_marshed[MAX_AUTH_BYTES];
80 u_int au_mpos; /* xdr pos at end of marshed */
81 };
82 #define AUTH_PRIVATE(auth) ((struct audata *)auth->ah_private)
83
84 /*
85 * Create a unix style authenticator.
86 * Returns an auth handle with the given stuff in it.
87 */
88 AUTH *
authunix_create(char * machname,u_int uid,u_int gid,int len,u_int * aup_gids)89 authunix_create(char *machname, u_int uid, u_int gid, int len, u_int *aup_gids)
90 {
91 struct authunix_parms aup;
92 char mymem[MAX_AUTH_BYTES];
93 struct timeval now;
94 XDR xdrs;
95 AUTH *auth;
96 struct audata *au;
97
98 /*
99 * Allocate and set up auth handle
100 */
101 au = NULL;
102 auth = mem_alloc(sizeof(*auth));
103 #ifndef _KERNEL
104 if (auth == NULL) {
105 warnx("authunix_create: out of memory");
106 goto cleanup_authunix_create;
107 }
108 #endif
109 au = mem_alloc(sizeof(*au));
110 #ifndef _KERNEL
111 if (au == NULL) {
112 warnx("authunix_create: out of memory");
113 goto cleanup_authunix_create;
114 }
115 #endif
116 auth->ah_ops = authunix_ops();
117 auth->ah_private = (caddr_t)au;
118 auth->ah_verf = au->au_shcred = _null_auth;
119 au->au_shfaults = 0;
120 au->au_origcred.oa_base = NULL;
121
122 /*
123 * fill in param struct from the given params
124 */
125 (void)gettimeofday(&now, NULL);
126 aup.aup_time = now.tv_sec;
127 aup.aup_machname = machname;
128 aup.aup_uid = uid;
129 aup.aup_gid = gid;
130 aup.aup_len = (u_int)len;
131 aup.aup_gids = aup_gids;
132
133 /*
134 * Serialize the parameters into origcred
135 */
136 xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
137 if (! xdr_authunix_parms(&xdrs, &aup))
138 abort();
139 au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
140 au->au_origcred.oa_flavor = AUTH_UNIX;
141 #ifdef _KERNEL
142 au->au_origcred.oa_base = mem_alloc((u_int) len);
143 #else
144 if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
145 warnx("authunix_create: out of memory");
146 goto cleanup_authunix_create;
147 }
148 #endif
149 memmove(au->au_origcred.oa_base, mymem, (size_t)len);
150
151 /*
152 * set auth handle to reflect new cred.
153 */
154 auth->ah_cred = au->au_origcred;
155 marshal_new_auth(auth);
156 return (auth);
157 #ifndef _KERNEL
158 cleanup_authunix_create:
159 if (auth)
160 mem_free(auth, sizeof(*auth));
161 if (au) {
162 if (au->au_origcred.oa_base)
163 mem_free(au->au_origcred.oa_base, (u_int)len);
164 mem_free(au, sizeof(*au));
165 }
166 return (NULL);
167 #endif
168 }
169
170 /*
171 * Returns an auth handle with parameters determined by doing lots of
172 * syscalls.
173 */
174 AUTH *
authunix_create_default(void)175 authunix_create_default(void)
176 {
177 AUTH *auth;
178 int ngids;
179 long ngids_max;
180 char machname[MAXHOSTNAMELEN + 1];
181 uid_t uid;
182 gid_t gid;
183 gid_t *gids;
184
185 ngids_max = sysconf(_SC_NGROUPS_MAX) + 1;
186 gids = malloc(sizeof(gid_t) * ngids_max);
187 if (gids == NULL)
188 return (NULL);
189
190 if (gethostname(machname, sizeof machname) == -1)
191 abort();
192 machname[sizeof(machname) - 1] = 0;
193 uid = geteuid();
194 gid = getegid();
195 if ((ngids = getgroups(ngids_max, gids)) < 0)
196 abort();
197 if (ngids > NGRPS)
198 ngids = NGRPS;
199 /* XXX: interface problem; we should translate from uid_t and gid_t */
200 auth = authunix_create(machname, uid, gid, ngids, gids);
201 free(gids);
202 return (auth);
203 }
204
205 /*
206 * authunix operations
207 */
208
209 /* ARGSUSED */
210 static void
authunix_nextverf(AUTH * auth)211 authunix_nextverf(AUTH *auth)
212 {
213 /* no action necessary */
214 }
215
216 static bool_t
authunix_marshal(AUTH * auth,XDR * xdrs)217 authunix_marshal(AUTH *auth, XDR *xdrs)
218 {
219 struct audata *au;
220
221 assert(auth != NULL);
222 assert(xdrs != NULL);
223
224 au = AUTH_PRIVATE(auth);
225 return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
226 }
227
228 static bool_t
authunix_validate(AUTH * auth,struct opaque_auth * verf)229 authunix_validate(AUTH *auth, struct opaque_auth *verf)
230 {
231 struct audata *au;
232 XDR xdrs;
233
234 assert(auth != NULL);
235 assert(verf != NULL);
236
237 if (verf->oa_flavor == AUTH_SHORT) {
238 au = AUTH_PRIVATE(auth);
239 xdrmem_create(&xdrs, verf->oa_base, verf->oa_length,
240 XDR_DECODE);
241
242 if (au->au_shcred.oa_base != NULL) {
243 mem_free(au->au_shcred.oa_base,
244 au->au_shcred.oa_length);
245 au->au_shcred.oa_base = NULL;
246 }
247 if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
248 auth->ah_cred = au->au_shcred;
249 } else {
250 xdrs.x_op = XDR_FREE;
251 (void)xdr_opaque_auth(&xdrs, &au->au_shcred);
252 au->au_shcred.oa_base = NULL;
253 auth->ah_cred = au->au_origcred;
254 }
255 marshal_new_auth(auth);
256 }
257 return (TRUE);
258 }
259
260 static bool_t
authunix_refresh(AUTH * auth,void * dummy)261 authunix_refresh(AUTH *auth, void *dummy)
262 {
263 struct audata *au = AUTH_PRIVATE(auth);
264 struct authunix_parms aup;
265 struct timeval now;
266 XDR xdrs;
267 int stat;
268
269 assert(auth != NULL);
270
271 if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
272 /* there is no hope. Punt */
273 return (FALSE);
274 }
275 au->au_shfaults ++;
276
277 /* first deserialize the creds back into a struct authunix_parms */
278 aup.aup_machname = NULL;
279 aup.aup_gids = NULL;
280 xdrmem_create(&xdrs, au->au_origcred.oa_base,
281 au->au_origcred.oa_length, XDR_DECODE);
282 stat = xdr_authunix_parms(&xdrs, &aup);
283 if (! stat)
284 goto done;
285
286 /* update the time and serialize in place */
287 (void)gettimeofday(&now, NULL);
288 aup.aup_time = now.tv_sec;
289 xdrs.x_op = XDR_ENCODE;
290 XDR_SETPOS(&xdrs, 0);
291 stat = xdr_authunix_parms(&xdrs, &aup);
292 if (! stat)
293 goto done;
294 auth->ah_cred = au->au_origcred;
295 marshal_new_auth(auth);
296 done:
297 /* free the struct authunix_parms created by deserializing */
298 xdrs.x_op = XDR_FREE;
299 (void)xdr_authunix_parms(&xdrs, &aup);
300 XDR_DESTROY(&xdrs);
301 return (stat);
302 }
303
304 static void
authunix_destroy(AUTH * auth)305 authunix_destroy(AUTH *auth)
306 {
307 struct audata *au;
308
309 assert(auth != NULL);
310
311 au = AUTH_PRIVATE(auth);
312 mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
313
314 if (au->au_shcred.oa_base != NULL)
315 mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
316
317 mem_free(auth->ah_private, sizeof(struct audata));
318
319 if (auth->ah_verf.oa_base != NULL)
320 mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
321
322 mem_free(auth, sizeof(*auth));
323 }
324
325 /*
326 * Marshals (pre-serializes) an auth struct.
327 * sets private data, au_marshed and au_mpos
328 */
329 static void
marshal_new_auth(AUTH * auth)330 marshal_new_auth(AUTH *auth)
331 {
332 XDR xdr_stream;
333 XDR *xdrs = &xdr_stream;
334 struct audata *au;
335
336 assert(auth != NULL);
337
338 au = AUTH_PRIVATE(auth);
339 xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
340 if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
341 (! xdr_opaque_auth(xdrs, &(auth->ah_verf))))
342 warnx("auth_none.c - Fatal marshalling problem");
343 else
344 au->au_mpos = XDR_GETPOS(xdrs);
345 XDR_DESTROY(xdrs);
346 }
347
348 static struct auth_ops *
authunix_ops(void)349 authunix_ops(void)
350 {
351 static struct auth_ops ops;
352
353 /* VARIABLES PROTECTED BY ops_lock: ops */
354
355 mutex_lock(&ops_lock);
356 if (ops.ah_nextverf == NULL) {
357 ops.ah_nextverf = authunix_nextverf;
358 ops.ah_marshal = authunix_marshal;
359 ops.ah_validate = authunix_validate;
360 ops.ah_refresh = authunix_refresh;
361 ops.ah_destroy = authunix_destroy;
362 }
363 mutex_unlock(&ops_lock);
364 return (&ops);
365 }
366