xref: /netbsd-src/lib/libc/rpc/auth_unix.c (revision d9158b13b5dfe46201430699a3f7a235ecf28df3)
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 #if defined(LIBC_SCCS) && !defined(lint)
31 /*static char *sccsid = "from: @(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro";*/
32 /*static char *sccsid = "from: @(#)auth_unix.c	2.2 88/08/01 4.0 RPCSRC";*/
33 static char *rcsid = "$Id: auth_unix.c,v 1.1 1993/10/07 07:29:37 cgd Exp $";
34 #endif
35 
36 /*
37  * auth_unix.c, Implements UNIX style authentication parameters.
38  *
39  * Copyright (C) 1984, Sun Microsystems, Inc.
40  *
41  * The system is very weak.  The client uses no encryption for it's
42  * credentials and only sends null verifiers.  The server sends backs
43  * null verifiers or optionally a verifier that suggests a new short hand
44  * for the credentials.
45  *
46  */
47 
48 #include <stdio.h>
49 #include <stdlib.h>
50 
51 #include <rpc/types.h>
52 #include <rpc/xdr.h>
53 #include <rpc/auth.h>
54 #include <rpc/auth_unix.h>
55 
56 /*
57  * Unix authenticator operations vector
58  */
59 static void	authunix_nextverf();
60 static bool_t	authunix_marshal();
61 static bool_t	authunix_validate();
62 static bool_t	authunix_refresh();
63 static void	authunix_destroy();
64 
65 static struct auth_ops auth_unix_ops = {
66 	authunix_nextverf,
67 	authunix_marshal,
68 	authunix_validate,
69 	authunix_refresh,
70 	authunix_destroy
71 };
72 
73 /*
74  * This struct is pointed to by the ah_private field of an auth_handle.
75  */
76 struct audata {
77 	struct opaque_auth	au_origcred;	/* original credentials */
78 	struct opaque_auth	au_shcred;	/* short hand cred */
79 	u_long			au_shfaults;	/* short hand cache faults */
80 	char			au_marshed[MAX_AUTH_BYTES];
81 	u_int			au_mpos;	/* xdr pos at end of marshed */
82 };
83 #define	AUTH_PRIVATE(auth)	((struct audata *)auth->ah_private)
84 
85 static bool_t marshal_new_auth();
86 
87 
88 /*
89  * Create a unix style authenticator.
90  * Returns an auth handle with the given stuff in it.
91  */
92 AUTH *
93 authunix_create(machname, uid, gid, len, aup_gids)
94 	char *machname;
95 	int uid;
96 	int gid;
97 	register int len;
98 	int *aup_gids;
99 {
100 	struct authunix_parms aup;
101 	char mymem[MAX_AUTH_BYTES];
102 	struct timeval now;
103 	XDR xdrs;
104 	register AUTH *auth;
105 	register struct audata *au;
106 
107 	/*
108 	 * Allocate and set up auth handle
109 	 */
110 	auth = (AUTH *)mem_alloc(sizeof(*auth));
111 #ifndef KERNEL
112 	if (auth == NULL) {
113 		(void)fprintf(stderr, "authunix_create: out of memory\n");
114 		return (NULL);
115 	}
116 #endif
117 	au = (struct audata *)mem_alloc(sizeof(*au));
118 #ifndef KERNEL
119 	if (au == NULL) {
120 		(void)fprintf(stderr, "authunix_create: out of memory\n");
121 		return (NULL);
122 	}
123 #endif
124 	auth->ah_ops = &auth_unix_ops;
125 	auth->ah_private = (caddr_t)au;
126 	auth->ah_verf = au->au_shcred = _null_auth;
127 	au->au_shfaults = 0;
128 
129 	/*
130 	 * fill in param struct from the given params
131 	 */
132 	(void)gettimeofday(&now,  (struct timezone *)0);
133 	aup.aup_time = now.tv_sec;
134 	aup.aup_machname = machname;
135 	aup.aup_uid = uid;
136 	aup.aup_gid = gid;
137 	aup.aup_len = (u_int)len;
138 	aup.aup_gids = aup_gids;
139 
140 	/*
141 	 * Serialize the parameters into origcred
142 	 */
143 	xdrmem_create(&xdrs, mymem, MAX_AUTH_BYTES, XDR_ENCODE);
144 	if (! xdr_authunix_parms(&xdrs, &aup))
145 		abort();
146 	au->au_origcred.oa_length = len = XDR_GETPOS(&xdrs);
147 	au->au_origcred.oa_flavor = AUTH_UNIX;
148 #ifdef KERNEL
149 	au->au_origcred.oa_base = mem_alloc((u_int) len);
150 #else
151 	if ((au->au_origcred.oa_base = mem_alloc((u_int) len)) == NULL) {
152 		(void)fprintf(stderr, "authunix_create: out of memory\n");
153 		return (NULL);
154 	}
155 #endif
156 	bcopy(mymem, au->au_origcred.oa_base, (u_int)len);
157 
158 	/*
159 	 * set auth handle to reflect new cred.
160 	 */
161 	auth->ah_cred = au->au_origcred;
162 	marshal_new_auth(auth);
163 	return (auth);
164 }
165 
166 /*
167  * Returns an auth handle with parameters determined by doing lots of
168  * syscalls.
169  */
170 AUTH *
171 authunix_create_default()
172 {
173 	register int len;
174 	char machname[MAX_MACHINE_NAME + 1];
175 	register int uid;
176 	register int gid;
177 	int gids[NGRPS];
178 
179 	if (gethostname(machname, MAX_MACHINE_NAME) == -1)
180 		abort();
181 	machname[MAX_MACHINE_NAME] = 0;
182 	uid = geteuid();
183 	gid = getegid();
184 	if ((len = getgroups(NGRPS, gids)) < 0)
185 		abort();
186 	return (authunix_create(machname, uid, gid, len, gids));
187 }
188 
189 /*
190  * authunix operations
191  */
192 
193 static void
194 authunix_nextverf(auth)
195 	AUTH *auth;
196 {
197 	/* no action necessary */
198 }
199 
200 static bool_t
201 authunix_marshal(auth, xdrs)
202 	AUTH *auth;
203 	XDR *xdrs;
204 {
205 	register struct audata *au = AUTH_PRIVATE(auth);
206 
207 	return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
208 }
209 
210 static bool_t
211 authunix_validate(auth, verf)
212 	register AUTH *auth;
213 	struct opaque_auth verf;
214 {
215 	register struct audata *au;
216 	XDR xdrs;
217 
218 	if (verf.oa_flavor == AUTH_SHORT) {
219 		au = AUTH_PRIVATE(auth);
220 		xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
221 
222 		if (au->au_shcred.oa_base != NULL) {
223 			mem_free(au->au_shcred.oa_base,
224 			    au->au_shcred.oa_length);
225 			au->au_shcred.oa_base = NULL;
226 		}
227 		if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
228 			auth->ah_cred = au->au_shcred;
229 		} else {
230 			xdrs.x_op = XDR_FREE;
231 			(void)xdr_opaque_auth(&xdrs, &au->au_shcred);
232 			au->au_shcred.oa_base = NULL;
233 			auth->ah_cred = au->au_origcred;
234 		}
235 		marshal_new_auth(auth);
236 	}
237 	return (TRUE);
238 }
239 
240 static bool_t
241 authunix_refresh(auth)
242 	register AUTH *auth;
243 {
244 	register struct audata *au = AUTH_PRIVATE(auth);
245 	struct authunix_parms aup;
246 	struct timeval now;
247 	XDR xdrs;
248 	register int stat;
249 
250 	if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
251 		/* there is no hope.  Punt */
252 		return (FALSE);
253 	}
254 	au->au_shfaults ++;
255 
256 	/* first deserialize the creds back into a struct authunix_parms */
257 	aup.aup_machname = NULL;
258 	aup.aup_gids = (int *)NULL;
259 	xdrmem_create(&xdrs, au->au_origcred.oa_base,
260 	    au->au_origcred.oa_length, XDR_DECODE);
261 	stat = xdr_authunix_parms(&xdrs, &aup);
262 	if (! stat)
263 		goto done;
264 
265 	/* update the time and serialize in place */
266 	(void)gettimeofday(&now, (struct timezone *)0);
267 	aup.aup_time = now.tv_sec;
268 	xdrs.x_op = XDR_ENCODE;
269 	XDR_SETPOS(&xdrs, 0);
270 	stat = xdr_authunix_parms(&xdrs, &aup);
271 	if (! stat)
272 		goto done;
273 	auth->ah_cred = au->au_origcred;
274 	marshal_new_auth(auth);
275 done:
276 	/* free the struct authunix_parms created by deserializing */
277 	xdrs.x_op = XDR_FREE;
278 	(void)xdr_authunix_parms(&xdrs, &aup);
279 	XDR_DESTROY(&xdrs);
280 	return (stat);
281 }
282 
283 static void
284 authunix_destroy(auth)
285 	register AUTH *auth;
286 {
287 	register struct audata *au = AUTH_PRIVATE(auth);
288 
289 	mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
290 
291 	if (au->au_shcred.oa_base != NULL)
292 		mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
293 
294 	mem_free(auth->ah_private, sizeof(struct audata));
295 
296 	if (auth->ah_verf.oa_base != NULL)
297 		mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
298 
299 	mem_free((caddr_t)auth, sizeof(*auth));
300 }
301 
302 /*
303  * Marshals (pre-serializes) an auth struct.
304  * sets private data, au_marshed and au_mpos
305  */
306 static bool_t
307 marshal_new_auth(auth)
308 	register AUTH *auth;
309 {
310 	XDR		xdr_stream;
311 	register XDR	*xdrs = &xdr_stream;
312 	register struct audata *au = AUTH_PRIVATE(auth);
313 
314 	xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
315 	if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
316 	    (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
317 		perror("auth_none.c - Fatal marshalling problem");
318 	} else {
319 		au->au_mpos = XDR_GETPOS(xdrs);
320 	}
321 	XDR_DESTROY(xdrs);
322 }
323