xref: /original-bsd/lib/librpc/rpc/auth_unix.c (revision 5f963634)
1 /* @(#)auth_unix.c	2.2 88/08/01 4.0 RPCSRC */
2 /*
3  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
4  * unrestricted use provided that this legend is included on all tape
5  * media and as a part of the software program in whole or part.  Users
6  * may copy or modify Sun RPC without charge, but are not authorized
7  * to license or distribute it to anyone else except as part of a product or
8  * program developed by the user.
9  *
10  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
11  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
12  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
13  *
14  * Sun RPC is provided with no support and without any obligation on the
15  * part of Sun Microsystems, Inc. to assist in its use, correction,
16  * modification or enhancement.
17  *
18  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
19  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
20  * OR ANY PART THEREOF.
21  *
22  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
23  * or profits or other special, indirect and consequential damages, even if
24  * Sun has been advised of the possibility of such damages.
25  *
26  * Sun Microsystems, Inc.
27  * 2550 Garcia Avenue
28  * Mountain View, California  94043
29  */
30 #if !defined(lint) && defined(SCCSIDS)
31 static char sccsid[] = "@(#)auth_unix.c 1.19 87/08/11 Copyr 1984 Sun Micro";
32 #endif
33 
34 /*
35  * auth_unix.c, Implements UNIX style authentication parameters.
36  *
37  * Copyright (C) 1984, Sun Microsystems, Inc.
38  *
39  * The system is very weak.  The client uses no encryption for it's
40  * credentials and only sends null verifiers.  The server sends backs
41  * null verifiers or optionally a verifier that suggests a new short hand
42  * for the credentials.
43  *
44  */
45 
46 #include <stdio.h>
47 
48 #include <rpc/types.h>
49 #include <rpc/xdr.h>
50 #include <rpc/auth.h>
51 #include <rpc/auth_unix.h>
52 
53 /*
54  * Unix authenticator operations vector
55  */
56 static void	authunix_nextverf();
57 static bool_t	authunix_marshal();
58 static bool_t	authunix_validate();
59 static bool_t	authunix_refresh();
60 static void	authunix_destroy();
61 
62 static struct auth_ops auth_unix_ops = {
63 	authunix_nextverf,
64 	authunix_marshal,
65 	authunix_validate,
66 	authunix_refresh,
67 	authunix_destroy
68 };
69 
70 /*
71  * This struct is pointed to by the ah_private field of an auth_handle.
72  */
73 struct audata {
74 	struct opaque_auth	au_origcred;	/* original credentials */
75 	struct opaque_auth	au_shcred;	/* short hand cred */
76 	u_long			au_shfaults;	/* short hand cache faults */
77 	char			au_marshed[MAX_AUTH_BYTES];
78 	u_int			au_mpos;	/* xdr pos at end of marshed */
79 };
80 #define	AUTH_PRIVATE(auth)	((struct audata *)auth->ah_private)
81 
82 static bool_t marshal_new_auth();
83 
84 
85 /*
86  * Create a unix style authenticator.
87  * Returns an auth handle with the given stuff in it.
88  */
89 AUTH *
authunix_create(machname,uid,gid,len,aup_gids)90 authunix_create(machname, uid, gid, len, aup_gids)
91 	char *machname;
92 	int uid;
93 	int gid;
94 	register int len;
95 	int *aup_gids;
96 {
97 	struct authunix_parms aup;
98 	char mymem[MAX_AUTH_BYTES];
99 	struct timeval now;
100 	XDR xdrs;
101 	register AUTH *auth;
102 	register struct audata *au;
103 
104 	/*
105 	 * Allocate and set up auth handle
106 	 */
107 	auth = (AUTH *)mem_alloc(sizeof(*auth));
108 #ifndef KERNEL
109 	if (auth == NULL) {
110 		(void)fprintf(stderr, "authunix_create: out of memory\n");
111 		return (NULL);
112 	}
113 #endif
114 	au = (struct audata *)mem_alloc(sizeof(*au));
115 #ifndef KERNEL
116 	if (au == NULL) {
117 		(void)fprintf(stderr, "authunix_create: out of memory\n");
118 		return (NULL);
119 	}
120 #endif
121 	auth->ah_ops = &auth_unix_ops;
122 	auth->ah_private = (caddr_t)au;
123 	auth->ah_verf = au->au_shcred = _null_auth;
124 	au->au_shfaults = 0;
125 
126 	/*
127 	 * fill in param struct from the given params
128 	 */
129 	(void)gettimeofday(&now,  (struct timezone *)0);
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 		(void)fprintf(stderr, "authunix_create: out of memory\n");
150 		return (NULL);
151 	}
152 #endif
153 	bcopy(mymem, au->au_origcred.oa_base, (u_int)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 }
162 
163 /*
164  * Some servers will refuse mounts if the group list is larger
165  * than it expects (like 8). This allows the application to set
166  * the maximum size of the group list that will be sent.
167  */
168 
169 static maxgrplist = NGRPS;
170 
set_rpc_maxgrouplist(num)171 set_rpc_maxgrouplist(num)
172 	int num;
173 {
174 
175 	if (num < NGRPS)
176 		maxgrplist = num;
177 }
178 
179 /*
180  * Returns an auth handle with parameters determined by doing lots of
181  * syscalls.
182  */
183 AUTH *
authunix_create_default()184 authunix_create_default()
185 {
186 	register int len;
187 	char machname[MAX_MACHINE_NAME + 1];
188 	register int uid;
189 	register int gid;
190 	int gids[NGRPS];
191 
192 	if (gethostname(machname, MAX_MACHINE_NAME) == -1)
193 		abort();
194 	machname[MAX_MACHINE_NAME] = 0;
195 	uid = geteuid();
196 	gid = getegid();
197 	if ((len = getgroups(NGRPS, gids)) < 0)
198 		abort();
199 	if (len > maxgrplist)
200 		len = maxgrplist;
201 	return (authunix_create(machname, uid, gid, len, gids));
202 }
203 
204 /*
205  * authunix operations
206  */
207 
208 static void
authunix_nextverf(auth)209 authunix_nextverf(auth)
210 	AUTH *auth;
211 {
212 	/* no action necessary */
213 }
214 
215 static bool_t
authunix_marshal(auth,xdrs)216 authunix_marshal(auth, xdrs)
217 	AUTH *auth;
218 	XDR *xdrs;
219 {
220 	register struct audata *au = AUTH_PRIVATE(auth);
221 
222 	return (XDR_PUTBYTES(xdrs, au->au_marshed, au->au_mpos));
223 }
224 
225 static bool_t
authunix_validate(auth,verf)226 authunix_validate(auth, verf)
227 	register AUTH *auth;
228 	struct opaque_auth verf;
229 {
230 	register struct audata *au;
231 	XDR xdrs;
232 
233 	if (verf.oa_flavor == AUTH_SHORT) {
234 		au = AUTH_PRIVATE(auth);
235 		xdrmem_create(&xdrs, verf.oa_base, verf.oa_length, XDR_DECODE);
236 
237 		if (au->au_shcred.oa_base != NULL) {
238 			mem_free(au->au_shcred.oa_base,
239 			    au->au_shcred.oa_length);
240 			au->au_shcred.oa_base = NULL;
241 		}
242 		if (xdr_opaque_auth(&xdrs, &au->au_shcred)) {
243 			auth->ah_cred = au->au_shcred;
244 		} else {
245 			xdrs.x_op = XDR_FREE;
246 			(void)xdr_opaque_auth(&xdrs, &au->au_shcred);
247 			au->au_shcred.oa_base = NULL;
248 			auth->ah_cred = au->au_origcred;
249 		}
250 		marshal_new_auth(auth);
251 	}
252 	return (TRUE);
253 }
254 
255 static bool_t
authunix_refresh(auth)256 authunix_refresh(auth)
257 	register AUTH *auth;
258 {
259 	register struct audata *au = AUTH_PRIVATE(auth);
260 	struct authunix_parms aup;
261 	struct timeval now;
262 	XDR xdrs;
263 	register int stat;
264 
265 	if (auth->ah_cred.oa_base == au->au_origcred.oa_base) {
266 		/* there is no hope.  Punt */
267 		return (FALSE);
268 	}
269 	au->au_shfaults ++;
270 
271 	/* first deserialize the creds back into a struct authunix_parms */
272 	aup.aup_machname = NULL;
273 	aup.aup_gids = (int *)NULL;
274 	xdrmem_create(&xdrs, au->au_origcred.oa_base,
275 	    au->au_origcred.oa_length, XDR_DECODE);
276 	stat = xdr_authunix_parms(&xdrs, &aup);
277 	if (! stat)
278 		goto done;
279 
280 	/* update the time and serialize in place */
281 	(void)gettimeofday(&now, (struct timezone *)0);
282 	aup.aup_time = now.tv_sec;
283 	xdrs.x_op = XDR_ENCODE;
284 	XDR_SETPOS(&xdrs, 0);
285 	stat = xdr_authunix_parms(&xdrs, &aup);
286 	if (! stat)
287 		goto done;
288 	auth->ah_cred = au->au_origcred;
289 	marshal_new_auth(auth);
290 done:
291 	/* free the struct authunix_parms created by deserializing */
292 	xdrs.x_op = XDR_FREE;
293 	(void)xdr_authunix_parms(&xdrs, &aup);
294 	XDR_DESTROY(&xdrs);
295 	return (stat);
296 }
297 
298 static void
authunix_destroy(auth)299 authunix_destroy(auth)
300 	register AUTH *auth;
301 {
302 	register struct audata *au = AUTH_PRIVATE(auth);
303 
304 	mem_free(au->au_origcred.oa_base, au->au_origcred.oa_length);
305 
306 	if (au->au_shcred.oa_base != NULL)
307 		mem_free(au->au_shcred.oa_base, au->au_shcred.oa_length);
308 
309 	mem_free(auth->ah_private, sizeof(struct audata));
310 
311 	if (auth->ah_verf.oa_base != NULL)
312 		mem_free(auth->ah_verf.oa_base, auth->ah_verf.oa_length);
313 
314 	mem_free((caddr_t)auth, sizeof(*auth));
315 }
316 
317 /*
318  * Marshals (pre-serializes) an auth struct.
319  * sets private data, au_marshed and au_mpos
320  */
321 static bool_t
marshal_new_auth(auth)322 marshal_new_auth(auth)
323 	register AUTH *auth;
324 {
325 	XDR		xdr_stream;
326 	register XDR	*xdrs = &xdr_stream;
327 	register struct audata *au = AUTH_PRIVATE(auth);
328 
329 	xdrmem_create(xdrs, au->au_marshed, MAX_AUTH_BYTES, XDR_ENCODE);
330 	if ((! xdr_opaque_auth(xdrs, &(auth->ah_cred))) ||
331 	    (! xdr_opaque_auth(xdrs, &(auth->ah_verf)))) {
332 		perror("auth_none.c - Fatal marshalling problem");
333 	} else {
334 		au->au_mpos = XDR_GETPOS(xdrs);
335 	}
336 	XDR_DESTROY(xdrs);
337 }
338