xref: /titanic_41/usr/src/uts/common/syscall/acl.c (revision 524e558aae3e99de2bdab73592f925ea489fbe07)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved  	*/
28 
29 /*
30  * Portions of this source code were derived from Berkeley 4.3 BSD
31  * under license from the Regents of the University of California.
32  */
33 
34 #pragma ident	"%Z%%M%	%I%	%E% SMI"
35 
36 #include <sys/param.h>
37 #include <sys/isa_defs.h>
38 #include <sys/types.h>
39 #include <sys/sysmacros.h>
40 #include <sys/cred.h>
41 #include <sys/systm.h>
42 #include <sys/errno.h>
43 #include <sys/fcntl.h>
44 #include <sys/pathname.h>
45 #include <sys/vfs.h>
46 #include <sys/vnode.h>
47 #include <sys/file.h>
48 #include <sys/mode.h>
49 #include <sys/uio.h>
50 #include <sys/kmem.h>
51 #include <sys/filio.h>
52 #include <sys/acl.h>
53 #include <sys/cmn_err.h>
54 #include <acl/acl_common.h>
55 
56 #include <sys/unistd.h>
57 #include <sys/debug.h>
58 #include <fs/fs_subr.h>
59 
60 static int cacl(int cmd, int nentries, void *aclbufp,
61     vnode_t *vp, int *rv);
62 
63 /*
64  * Get/Set ACL of a file.
65  */
66 int
67 acl(const char *fname, int cmd, int nentries, void *aclbufp)
68 {
69 	struct vnode *vp;
70 	int error;
71 	int rv = 0;
72 	int estale_retry = 0;
73 
74 	/* Sanity check arguments */
75 	if (fname == NULL)
76 		return (set_errno(EINVAL));
77 lookup:
78 	error = lookupname((char *)fname, UIO_USERSPACE, FOLLOW, NULLVPP, &vp);
79 	if (error) {
80 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
81 			goto lookup;
82 		return (set_errno(error));
83 	}
84 
85 	error = cacl(cmd, nentries, aclbufp, vp, &rv);
86 	VN_RELE(vp);
87 	if (error) {
88 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
89 			goto lookup;
90 		return (set_errno(error));
91 	}
92 	return (rv);
93 }
94 
95 /*
96  * Get/Set ACL of a file with facl system call.
97  */
98 int
99 facl(int fdes, int cmd, int nentries, void *aclbufp)
100 {
101 	file_t *fp;
102 	int error;
103 	int rv = 0;
104 
105 	if ((fp = getf(fdes)) == NULL)
106 		return (set_errno(EBADF));
107 #ifdef C2_AUDIT
108 	if (fp->f_flag & FREVOKED) {
109 		releasef(fdes);
110 		return (set_errno(EBADF));
111 	}
112 #endif /* C2_AUDIT */
113 
114 	error = cacl(cmd, nentries, aclbufp, fp->f_vnode, &rv);
115 	releasef(fdes);
116 
117 	if (error)
118 		return (set_errno(error));
119 	return (rv);
120 }
121 
122 
123 /*
124  * Common code for acl() and facl().
125  */
126 static int
127 cacl(int cmd, int nentries, void *aclbufp, vnode_t *vp, int *rv)
128 {
129 	int		error;
130 	int		aclbsize;	/* size of acl list in bytes */
131 	int		dfaclbsize;	/* size of default acl list in bytes */
132 	int		numacls;
133 	caddr_t		uaddrp;
134 	aclent_t	*aclp, *aaclp;
135 	vsecattr_t	vsecattr;
136 
137 	ASSERT(vp);
138 
139 	bzero(&vsecattr, sizeof (vsecattr_t));
140 
141 	switch (cmd) {
142 
143 	case ACE_GETACLCNT:
144 	case GETACLCNT:
145 		if (cmd == GETACLCNT)
146 			vsecattr.vsa_mask = VSA_ACLCNT | VSA_DFACLCNT;
147 		else
148 			vsecattr.vsa_mask = VSA_ACECNT;
149 		if (error = VOP_GETSECATTR(vp, &vsecattr, 0, CRED()))
150 			return (error);
151 		*rv = vsecattr.vsa_aclcnt + vsecattr.vsa_dfaclcnt;
152 		if (vsecattr.vsa_aclcnt && vsecattr.vsa_aclentp) {
153 			kmem_free(vsecattr.vsa_aclentp,
154 			    vsecattr.vsa_aclcnt * sizeof (aclent_t));
155 		}
156 		if (vsecattr.vsa_dfaclcnt && vsecattr.vsa_dfaclentp) {
157 			kmem_free(vsecattr.vsa_dfaclentp,
158 			    vsecattr.vsa_dfaclcnt * sizeof (aclent_t));
159 		}
160 		break;
161 	case GETACL:
162 		/*
163 		 * Minimum ACL size is three entries so might as well
164 		 * bail out here.
165 		 */
166 		if (nentries < 3)
167 			return (EINVAL);
168 		/*
169 		 * NULL output buffer is also a pretty easy bail out.
170 		 */
171 		if (aclbufp == NULL)
172 			return (EFAULT);
173 		vsecattr.vsa_mask = VSA_ACL | VSA_ACLCNT | VSA_DFACL |
174 		    VSA_DFACLCNT;
175 		if (error = VOP_GETSECATTR(vp, &vsecattr, 0, CRED()))
176 			return (error);
177 		/* Check user's buffer is big enough */
178 		numacls = vsecattr.vsa_aclcnt + vsecattr.vsa_dfaclcnt;
179 		aclbsize = vsecattr.vsa_aclcnt * sizeof (aclent_t);
180 		dfaclbsize = vsecattr.vsa_dfaclcnt * sizeof (aclent_t);
181 		if (numacls > nentries) {
182 			error = ENOSPC;
183 			goto errout;
184 		}
185 		/* Sort the acl & default acl lists */
186 		if (vsecattr.vsa_aclcnt > 1)
187 			ksort((caddr_t)vsecattr.vsa_aclentp,
188 			vsecattr.vsa_aclcnt, sizeof (aclent_t), cmp2acls);
189 		if (vsecattr.vsa_dfaclcnt > 1)
190 			ksort((caddr_t)vsecattr.vsa_dfaclentp,
191 			vsecattr.vsa_dfaclcnt, sizeof (aclent_t), cmp2acls);
192 		/* Copy out acl's */
193 		uaddrp = (caddr_t)aclbufp;
194 		if (aclbsize > 0) {	/* bug #1262490 */
195 			if (copyout(vsecattr.vsa_aclentp, uaddrp, aclbsize)) {
196 				error = EFAULT;
197 				goto errout;
198 			}
199 		}
200 		/* Copy out default acl's */
201 		if (dfaclbsize > 0) {
202 			uaddrp += aclbsize;
203 			if (copyout(vsecattr.vsa_dfaclentp,
204 			    uaddrp, dfaclbsize)) {
205 				error = EFAULT;
206 				goto errout;
207 			}
208 		}
209 		*rv = numacls;
210 		if (vsecattr.vsa_aclcnt) {
211 			kmem_free(vsecattr.vsa_aclentp,
212 			    vsecattr.vsa_aclcnt * sizeof (aclent_t));
213 		}
214 		if (vsecattr.vsa_dfaclcnt) {
215 			kmem_free(vsecattr.vsa_dfaclentp,
216 			    vsecattr.vsa_dfaclcnt * sizeof (aclent_t));
217 		}
218 		break;
219 
220 	case ACE_GETACL:
221 		if (aclbufp == NULL)
222 			return (EFAULT);
223 
224 		vsecattr.vsa_mask = VSA_ACE | VSA_ACECNT;
225 		if (error = VOP_GETSECATTR(vp, &vsecattr, 0, CRED()))
226 			return (error);
227 
228 		aclbsize = vsecattr.vsa_aclcnt * sizeof (ace_t);
229 		if (vsecattr.vsa_aclcnt > nentries) {
230 			error = ENOSPC;
231 			goto errout;
232 		}
233 
234 		if (aclbsize > 0) {
235 			if ((error = copyout(vsecattr.vsa_aclentp,
236 			    aclbufp, aclbsize)) != 0) {
237 				goto errout;
238 			}
239 		}
240 
241 		*rv = vsecattr.vsa_aclcnt;
242 		if (vsecattr.vsa_aclcnt) {
243 			kmem_free(vsecattr.vsa_aclentp,
244 			    vsecattr.vsa_aclcnt * sizeof (ace_t));
245 		}
246 		break;
247 
248 	case SETACL:
249 		/*
250 		 * Minimum ACL size is three entries so might as well
251 		 * bail out here.  Also limit request size to prevent user
252 		 * from allocating too much kernel memory.  Maximum size
253 		 * is MAX_ACL_ENTRIES for the ACL part and MAX_ACL_ENTRIES
254 		 * for the default ACL part. (bug 4058667)
255 		 */
256 		if (nentries < 3 || nentries > (MAX_ACL_ENTRIES * 2))
257 			return (EINVAL);
258 		/*
259 		 * NULL output buffer is also an easy bail out.
260 		 */
261 		if (aclbufp == NULL)
262 			return (EFAULT);
263 		vsecattr.vsa_mask = VSA_ACL;
264 		aclbsize = nentries * sizeof (aclent_t);
265 		vsecattr.vsa_aclentp = kmem_alloc(aclbsize, KM_SLEEP);
266 		aaclp = vsecattr.vsa_aclentp;
267 		vsecattr.vsa_aclcnt = nentries;
268 		uaddrp = (caddr_t)aclbufp;
269 		if (copyin(uaddrp, vsecattr.vsa_aclentp, aclbsize)) {
270 			kmem_free(aaclp, aclbsize);
271 			return (EFAULT);
272 		}
273 		/* Sort the acl list */
274 		ksort((caddr_t)vsecattr.vsa_aclentp,
275 		    vsecattr.vsa_aclcnt, sizeof (aclent_t), cmp2acls);
276 
277 		/* Break into acl and default acl lists */
278 		for (numacls = 0, aclp = vsecattr.vsa_aclentp;
279 		    numacls < vsecattr.vsa_aclcnt;
280 		    aclp++, numacls++) {
281 			if (aclp->a_type & ACL_DEFAULT)
282 				break;
283 		}
284 
285 		/* Find where defaults start (if any) */
286 		if (numacls < vsecattr.vsa_aclcnt) {
287 			vsecattr.vsa_mask |= VSA_DFACL;
288 			vsecattr.vsa_dfaclcnt = nentries - numacls;
289 			vsecattr.vsa_dfaclentp = aclp;
290 			vsecattr.vsa_aclcnt = numacls;
291 		}
292 		/* Adjust if they're all defaults */
293 		if (vsecattr.vsa_aclcnt == 0) {
294 			vsecattr.vsa_mask &= ~VSA_ACL;
295 			vsecattr.vsa_aclentp = NULL;
296 		}
297 		/* Only directories can have defaults */
298 		if (vsecattr.vsa_dfaclcnt && vp->v_type != VDIR) {
299 			kmem_free(aaclp, aclbsize);
300 			return (ENOTDIR);
301 		}
302 		(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
303 		if (error = VOP_SETSECATTR(vp, &vsecattr, 0, CRED())) {
304 			kmem_free(aaclp, aclbsize);
305 			VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
306 			return (error);
307 		}
308 
309 		/*
310 		 * Should return 0 upon success according to the man page
311 		 * and SVR4 semantics. (Bug #1214399: SETACL returns wrong rc)
312 		 */
313 		*rv = 0;
314 		kmem_free(aaclp, aclbsize);
315 		VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
316 		break;
317 
318 	case ACE_SETACL:
319 		if (nentries > (MAX_ACL_ENTRIES))
320 			return (EINVAL);
321 
322 		if (aclbufp == NULL)
323 			return (EFAULT);
324 
325 		vsecattr.vsa_mask = VSA_ACE;
326 		aclbsize = nentries * sizeof (ace_t);
327 		vsecattr.vsa_aclentp = kmem_alloc(aclbsize, KM_SLEEP);
328 		aaclp = vsecattr.vsa_aclentp;
329 		vsecattr.vsa_aclcnt = nentries;
330 		uaddrp = (caddr_t)aclbufp;
331 		if (copyin(uaddrp, vsecattr.vsa_aclentp, aclbsize)) {
332 			kmem_free(aaclp, aclbsize);
333 			return (EFAULT);
334 		}
335 		(void) VOP_RWLOCK(vp, V_WRITELOCK_TRUE, NULL);
336 		if (error = VOP_SETSECATTR(vp, &vsecattr, 0, CRED())) {
337 			kmem_free(aaclp, aclbsize);
338 			VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
339 			return (error);
340 		}
341 		*rv = 0;
342 		kmem_free(aaclp, aclbsize);
343 		VOP_RWUNLOCK(vp, V_WRITELOCK_TRUE, NULL);
344 		break;
345 
346 	default:
347 		return (EINVAL);
348 	}
349 
350 	return (0);
351 
352 errout:
353 	if (aclbsize && vsecattr.vsa_aclentp)
354 		kmem_free(vsecattr.vsa_aclentp, aclbsize);
355 	if (dfaclbsize && vsecattr.vsa_dfaclentp)
356 		kmem_free(vsecattr.vsa_dfaclentp, dfaclbsize);
357 	return (error);
358 }
359