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 (c) 2009, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright 2015 Nexenta Systems, Inc. All rights reserved.
24 */
25
26 /*
27 * Volume Copy Shadow Services (VSS) provides a way for users to
28 * restore/recover deleted files/directories.
29 * For the server to support VSS for Microsoft clients, there is
30 * two basic functions that need to be implemented.
31 * The first is to intercept the NT_TRANSACT_IOCTL command with
32 * the function code of FSCTL_SRV_ENUMERATE_SNAPSHOTS (0x00144064).
33 * This is to report the count or the count and list of snapshots
34 * for that share.
35 * The second function need to trap commands with the
36 * SMB_FLAGS2_REPARSE_PATH bit set in the smb header. This bit
37 * means that there is a @GMT token in path that needs to be
38 * processed. The @GMT token means to process this command, but
39 * in the snapshot.
40 */
41
42 #include <smbsrv/smb_kproto.h>
43 #include <smbsrv/string.h>
44 #include <smbsrv/winioctl.h>
45 #include <smbsrv/smb_door.h>
46
47 /* Size of the token on the wire due to encoding */
48 #define SMB_VSS_GMT_NET_SIZE(sr) (smb_ascii_or_unicode_null_len(sr) * \
49 SMB_VSS_GMT_SIZE)
50
51 #define SMB_VSS_COUNT_SIZE 16
52
53 static boolean_t smb_vss_is_gmttoken(const char *);
54 static const char *smb_vss_find_gmttoken(const char *);
55 static uint32_t smb_vss_encode_gmttokens(smb_request_t *, smb_fsctl_t *,
56 int32_t, smb_gmttoken_response_t *);
57 static void smb_vss_remove_first_token_from_path(char *);
58
59 static uint32_t smb_vss_get_count(smb_tree_t *, char *);
60 static void smb_vss_map_gmttoken(smb_tree_t *, char *, char *, time_t, char *);
61 static void smb_vss_get_snapshots(smb_tree_t *, char *,
62 uint32_t, smb_gmttoken_response_t *);
63 static void smb_vss_get_snapshots_free(smb_gmttoken_response_t *);
64 static int smb_vss_lookup_node(smb_request_t *sr, smb_node_t *, vnode_t *,
65 char *, smb_node_t *, smb_node_t **);
66
67 /*
68 * This is to respond to the nt_transact_ioctl to either respond with the
69 * number of snapshots, or to respond with the list. It needs to be sorted
70 * before the reply. If the the max data bytes to return is
71 * SMB_VSS_COUNT_SIZE, then all that is requested is the count, otherwise
72 * return the count and the list of @GMT tokens (one token for each
73 * snapshot).
74 */
75 uint32_t
76 smb_vss_enum_snapshots(smb_request_t *sr, smb_fsctl_t *fsctl)
77 {
78 uint32_t count = 0;
79 char *root_path;
80 uint32_t status = NT_STATUS_SUCCESS;
81 smb_node_t *tnode;
82 smb_gmttoken_response_t snaps;
83
84 ASSERT(sr->tid_tree);
85 ASSERT(sr->tid_tree->t_snode);
86
87 if (fsctl->MaxOutputResp < SMB_VSS_COUNT_SIZE)
88 return (NT_STATUS_INVALID_PARAMETER);
89
90 tnode = sr->tid_tree->t_snode;
91 root_path = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
92 if (smb_node_getmntpath(tnode, root_path, MAXPATHLEN) != 0)
93 return (NT_STATUS_INVALID_PARAMETER);
94
95 if (fsctl->MaxOutputResp == SMB_VSS_COUNT_SIZE) {
96 count = smb_vss_get_count(sr->tid_tree, root_path);
97 if (smb_mbc_encodef(fsctl->out_mbc, "lllw", count, 0,
98 (count * SMB_VSS_GMT_NET_SIZE(sr) +
99 smb_ascii_or_unicode_null_len(sr)), 0) != 0) {
100 status = NT_STATUS_INVALID_PARAMETER;
101 }
102 } else {
103 count = fsctl->MaxOutputResp / SMB_VSS_GMT_NET_SIZE(sr);
104
105 smb_vss_get_snapshots(sr->tid_tree, root_path,
106 count, &snaps);
107
108 status = smb_vss_encode_gmttokens(sr, fsctl, count, &snaps);
109
110 smb_vss_get_snapshots_free(&snaps);
111 }
112
113 kmem_free(root_path, MAXPATHLEN);
114 return (status);
115 }
116
117 /*
118 * sr - the request info, used to find root of dataset,
119 * unicode or ascii, where the share is rooted in the
120 * dataset
121 * root_node - root of the share
122 * cur_node - where in the share for the command
123 * buf - is the path for the command to be processed
124 * returned without @GMT if processed
125 * vss_cur_node - returned value for the snapshot version
126 * of the cur_node
127 * vss_root_node - returned value for the snapshot version
128 * of the root_node
129 *
130 * This routine is the processing for handling the
131 * SMB_FLAGS2_REPARSE_PATH bit being set in the smb header.
132 *
133 * By using the cur_node passed in, a new node is found or
134 * created that is the same place in the directory tree, but
135 * in the snapshot. We also use root_node to do the same for
136 * the root.
137 * Once the new smb node is found, the path is modified by
138 * removing the @GMT token from the path in the buf.
139 */
140 int
141 smb_vss_lookup_nodes(smb_request_t *sr, smb_node_t *root_node,
142 smb_node_t *cur_node, char *buf, smb_node_t **vss_cur_node,
143 smb_node_t **vss_root_node)
144 {
145 smb_arg_open_t *op = &sr->arg.open;
146 smb_node_t *tnode;
147 char *snapname, *path;
148 char *gmttoken;
149 char gmttok_buf[SMB_VSS_GMT_SIZE];
150 vnode_t *fsrootvp = NULL;
151 time_t toktime;
152 int err = 0;
153 boolean_t smb1;
154
155 if (sr->tid_tree == NULL)
156 return (ESTALE);
157
158 tnode = sr->tid_tree->t_snode;
159
160 ASSERT(tnode);
161 ASSERT(tnode->vp);
162 ASSERT(tnode->vp->v_vfsp);
163
164 smb1 = (sr->session->dialect < SMB_VERS_2_BASE);
165 if (smb1) {
166 const char *p;
167
168 /* get gmttoken from buf */
169 if ((p = smb_vss_find_gmttoken(buf)) == NULL)
170 return (ENOENT);
171
172 bcopy(p, gmttok_buf, SMB_VSS_GMT_SIZE);
173 gmttok_buf[SMB_VSS_GMT_SIZE - 1] = '\0';
174 gmttoken = gmttok_buf;
175 toktime = 0;
176 } else {
177 /* SMB2 and later */
178 gmttoken = NULL;
179 toktime = op->timewarp.tv_sec;
180 }
181
182 path = smb_srm_alloc(sr, MAXPATHLEN);
183 snapname = smb_srm_alloc(sr, MAXPATHLEN);
184
185 err = smb_node_getmntpath(tnode, path, MAXPATHLEN);
186 if (err != 0)
187 return (err);
188
189 /*
190 * Find the corresponding snapshot name. If snapname is
191 * empty after the map call, no such snapshot was found.
192 */
193 *snapname = '\0';
194 smb_vss_map_gmttoken(sr->tid_tree, path, gmttoken, toktime,
195 snapname);
196 if (*snapname == '\0')
197 return (ENOENT);
198
199 /* find snapshot nodes */
200 err = VFS_ROOT(tnode->vp->v_vfsp, &fsrootvp);
201 if (err != 0)
202 return (err);
203
204 /* find snapshot node corresponding to root_node */
205 err = smb_vss_lookup_node(sr, root_node, fsrootvp,
206 snapname, cur_node, vss_root_node);
207 if (err == 0) {
208 /* find snapshot node corresponding to cur_node */
209 err = smb_vss_lookup_node(sr, cur_node, fsrootvp,
210 snapname, cur_node, vss_cur_node);
211 if (err != 0)
212 smb_node_release(*vss_root_node);
213 }
214
215 VN_RELE(fsrootvp);
216
217 if (smb1)
218 smb_vss_remove_first_token_from_path(buf);
219
220 return (err);
221 }
222
223 /*
224 * Find snapshot node corresponding to 'node', and return it in
225 * 'vss_node', as follows:
226 * - find the path from fsrootvp to node, appending it to the
227 * the snapshot path
228 * - lookup the vnode and smb_node (vss_node).
229 */
230 static int
231 smb_vss_lookup_node(smb_request_t *sr, smb_node_t *node, vnode_t *fsrootvp,
232 char *snapname, smb_node_t *dnode, smb_node_t **vss_node)
233 {
234 char *p, *path;
235 int err, len;
236 vnode_t *vp = NULL;
237
238 *vss_node = NULL;
239
240 path = kmem_alloc(MAXPATHLEN, KM_SLEEP);
241 (void) snprintf(path, MAXPATHLEN, ".zfs/snapshot/%s/", snapname);
242 len = strlen(path);
243 p = path + len;
244
245 err = smb_node_getpath(node, fsrootvp, p, MAXPATHLEN - len);
246 if (err == 0) {
247 vp = smb_lookuppathvptovp(sr, path, fsrootvp, fsrootvp);
248 if (vp) {
249 *vss_node = smb_node_lookup(sr, NULL, zone_kcred(),
250 vp, snapname, dnode, NULL);
251 VN_RELE(vp);
252 }
253 }
254
255 kmem_free(path, MAXPATHLEN);
256
257 if (*vss_node != NULL)
258 return (0);
259
260 return (err ? err : ENOENT);
261 }
262
263
264 static boolean_t
265 smb_vss_is_gmttoken(const char *s)
266 {
267 char *t = "@GMT-NNNN.NN.NN-NN.NN.NN";
268 const char *str;
269 char *template;
270
271 template = t;
272 str = s;
273
274 while (*template) {
275 if (*template == 'N') {
276 if (!smb_isdigit(*str))
277 return (B_FALSE);
278 } else if (*template != *str) {
279 return (B_FALSE);
280 }
281
282 template++;
283 str++;
284 }
285
286 /* Make sure it is JUST the @GMT token */
287 if ((*str == '\0') || (*str == '/'))
288 return (B_TRUE);
289
290 return (B_FALSE);
291 }
292
293 static const char *
294 smb_vss_find_gmttoken(const char *path)
295 {
296 const char *p;
297
298 p = path;
299
300 while (*p) {
301 if (*p == '@' && smb_vss_is_gmttoken(p))
302 return (p);
303 p++;
304 }
305 return (NULL);
306 }
307
308 static uint32_t
309 smb_vss_encode_gmttokens(smb_request_t *sr, smb_fsctl_t *fsctl,
310 int32_t count, smb_gmttoken_response_t *snap_data)
311 {
312 uint32_t i;
313 uint32_t returned_count;
314 uint32_t num_gmttokens;
315 char **gmttokens;
316 uint32_t status = NT_STATUS_SUCCESS;
317 uint32_t data_size;
318
319 returned_count = snap_data->gtr_count;
320 num_gmttokens = snap_data->gtr_gmttokens.gtr_gmttokens_len;
321 gmttokens = snap_data->gtr_gmttokens.gtr_gmttokens_val;
322
323 if (returned_count > count)
324 status = NT_STATUS_BUFFER_TOO_SMALL;
325
326 data_size = returned_count * SMB_VSS_GMT_NET_SIZE(sr) +
327 smb_ascii_or_unicode_null_len(sr);
328
329 if (smb_mbc_encodef(fsctl->out_mbc, "lll", returned_count,
330 num_gmttokens, data_size) != 0)
331 return (NT_STATUS_INVALID_PARAMETER);
332
333 if (status == NT_STATUS_SUCCESS) {
334 for (i = 0; i < num_gmttokens; i++) {
335 if (smb_mbc_encodef(fsctl->out_mbc, "%u", sr,
336 *gmttokens) != 0)
337 status = NT_STATUS_INVALID_PARAMETER;
338 gmttokens++;
339 }
340 }
341
342 return (status);
343 }
344
345 /* This removes the first @GMT from the path */
346 static void
347 smb_vss_remove_first_token_from_path(char *path)
348 {
349 boolean_t found;
350 char *src, *dest;
351
352 src = path;
353 dest = path;
354
355 found = B_FALSE;
356
357 while (*src != '\0') {
358 if (!found && smb_vss_is_gmttoken(src)) {
359 src += SMB_VSS_GMT_SIZE - 1;
360 if (*src == '/')
361 src += 1;
362 found = B_TRUE;
363 continue;
364 }
365 *dest = *src;
366 src++;
367 dest++;
368 }
369 *dest = *src;
370 }
371
372 /*
373 * This returns the number of snapshots for the dataset
374 * of the path provided.
375 */
376 static uint32_t
377 smb_vss_get_count(smb_tree_t *tree, char *resource_path)
378 {
379 uint32_t count = 0;
380 int rc;
381 smb_string_t path;
382
383 path.buf = resource_path;
384
385 rc = smb_kdoor_upcall(tree->t_server, SMB_DR_VSS_GET_COUNT,
386 &path, smb_string_xdr, &count, xdr_uint32_t);
387
388 if (rc != 0)
389 count = 0;
390
391 return (count);
392 }
393
394 /*
395 * This takes a path for the root of the dataset and gets the counts of
396 * snapshots for that dataset and the list of @GMT tokens (one for each
397 * snapshot) up to the count provided.
398 *
399 * Call smb_vss_get_snapshots_free after to free up the data.
400 */
401 static void
402 smb_vss_get_snapshots(smb_tree_t *tree, char *resource_path,
403 uint32_t count, smb_gmttoken_response_t *gmttokens)
404 {
405 smb_gmttoken_query_t request;
406
407 request.gtq_count = count;
408 request.gtq_path = resource_path;
409 bzero(gmttokens, sizeof (smb_gmttoken_response_t));
410
411 (void) smb_kdoor_upcall(tree->t_server, SMB_DR_VSS_GET_SNAPSHOTS,
412 &request, smb_gmttoken_query_xdr,
413 gmttokens, smb_gmttoken_response_xdr);
414 }
415
416 static void
417 smb_vss_get_snapshots_free(smb_gmttoken_response_t *reply)
418 {
419 xdr_free(smb_gmttoken_response_xdr, (char *)reply);
420 }
421
422 /*
423 * Returns the snapshot name for the @GMT token provided for the dataset
424 * of the path. If the snapshot cannot be found, a string with a NULL
425 * is returned.
426 */
427 static void
428 smb_vss_map_gmttoken(smb_tree_t *tree, char *path, char *gmttoken,
429 time_t toktime, char *snapname)
430 {
431 smb_gmttoken_snapname_t request;
432 smb_string_t result;
433
434 bzero(&result, sizeof (smb_string_t));
435 result.buf = snapname;
436
437 request.gts_path = path;
438 request.gts_gmttoken = gmttoken;
439 request.gts_toktime = toktime;
440
441 (void) smb_kdoor_upcall(tree->t_server, SMB_DR_VSS_MAP_GMTTOKEN,
442 &request, smb_gmttoken_snapname_xdr,
443 &result, smb_string_xdr);
444 }