xref: /linux/fs/ceph/xattr.c (revision 49bda4826843be0ef97a162009a29ea3a63f3935)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/ceph/ceph_debug.h>
3 #include <linux/ceph/pagelist.h>
4 
5 #include "super.h"
6 #include "mds_client.h"
7 
8 #include <linux/ceph/decode.h>
9 
10 #include <linux/xattr.h>
11 #include <linux/security.h>
12 #include <linux/posix_acl_xattr.h>
13 #include <linux/slab.h>
14 
15 #define XATTR_CEPH_PREFIX "ceph."
16 #define XATTR_CEPH_PREFIX_LEN (sizeof (XATTR_CEPH_PREFIX) - 1)
17 
18 static int __remove_xattr(struct ceph_inode_info *ci,
19 			  struct ceph_inode_xattr *xattr);
20 
ceph_is_valid_xattr(const char * name)21 static bool ceph_is_valid_xattr(const char *name)
22 {
23 	return !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) ||
24 	       !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) ||
25 	       !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) ||
26 	       !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
27 }
28 
29 /*
30  * These define virtual xattrs exposing the recursive directory
31  * statistics and layout metadata.
32  */
33 struct ceph_vxattr {
34 	char *name;
35 	size_t name_size;	/* strlen(name) + 1 (for '\0') */
36 	ssize_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
37 			       size_t size);
38 	bool (*exists_cb)(struct ceph_inode_info *ci);
39 	unsigned int flags;
40 };
41 
42 #define VXATTR_FLAG_READONLY		(1<<0)
43 #define VXATTR_FLAG_HIDDEN		(1<<1)
44 #define VXATTR_FLAG_RSTAT		(1<<2)
45 #define VXATTR_FLAG_DIRSTAT		(1<<3)
46 
47 /* layouts */
48 
ceph_vxattrcb_layout_exists(struct ceph_inode_info * ci)49 static bool ceph_vxattrcb_layout_exists(struct ceph_inode_info *ci)
50 {
51 	struct ceph_file_layout *fl = &ci->i_layout;
52 	return (fl->stripe_unit > 0 || fl->stripe_count > 0 ||
53 		fl->object_size > 0 || fl->pool_id >= 0 ||
54 		rcu_dereference_raw(fl->pool_ns) != NULL);
55 }
56 
ceph_vxattrcb_layout(struct ceph_inode_info * ci,char * val,size_t size)57 static ssize_t ceph_vxattrcb_layout(struct ceph_inode_info *ci, char *val,
58 				    size_t size)
59 {
60 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(ci->netfs.inode.i_sb);
61 	struct ceph_client *cl = fsc->client;
62 	struct ceph_osd_client *osdc = &fsc->client->osdc;
63 	struct ceph_string *pool_ns;
64 	s64 pool = ci->i_layout.pool_id;
65 	const char *pool_name;
66 	const char *ns_field = " pool_namespace=";
67 	char buf[128];
68 	size_t len, total_len = 0;
69 	ssize_t ret;
70 
71 	pool_ns = ceph_try_get_string(ci->i_layout.pool_ns);
72 
73 	doutc(cl, "%p\n", &ci->netfs.inode);
74 	down_read(&osdc->lock);
75 	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
76 	if (pool_name) {
77 		len = snprintf(buf, sizeof(buf),
78 		"stripe_unit=%u stripe_count=%u object_size=%u pool=",
79 		ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
80 	        ci->i_layout.object_size);
81 		total_len = len + strlen(pool_name);
82 	} else {
83 		len = snprintf(buf, sizeof(buf),
84 		"stripe_unit=%u stripe_count=%u object_size=%u pool=%lld",
85 		ci->i_layout.stripe_unit, ci->i_layout.stripe_count,
86 		ci->i_layout.object_size, pool);
87 		total_len = len;
88 	}
89 
90 	if (pool_ns)
91 		total_len += strlen(ns_field) + pool_ns->len;
92 
93 	ret = total_len;
94 	if (size >= total_len) {
95 		memcpy(val, buf, len);
96 		ret = len;
97 		if (pool_name) {
98 			len = strlen(pool_name);
99 			memcpy(val + ret, pool_name, len);
100 			ret += len;
101 		}
102 		if (pool_ns) {
103 			len = strlen(ns_field);
104 			memcpy(val + ret, ns_field, len);
105 			ret += len;
106 			memcpy(val + ret, pool_ns->str, pool_ns->len);
107 			ret += pool_ns->len;
108 		}
109 	}
110 	up_read(&osdc->lock);
111 	ceph_put_string(pool_ns);
112 	return ret;
113 }
114 
115 /*
116  * The convention with strings in xattrs is that they should not be NULL
117  * terminated, since we're returning the length with them. snprintf always
118  * NULL terminates however, so call it on a temporary buffer and then memcpy
119  * the result into place.
120  */
121 static __printf(3, 4)
ceph_fmt_xattr(char * val,size_t size,const char * fmt,...)122 int ceph_fmt_xattr(char *val, size_t size, const char *fmt, ...)
123 {
124 	int ret;
125 	va_list args;
126 	char buf[96]; /* NB: reevaluate size if new vxattrs are added */
127 
128 	va_start(args, fmt);
129 	ret = vsnprintf(buf, size ? sizeof(buf) : 0, fmt, args);
130 	va_end(args);
131 
132 	/* Sanity check */
133 	if (size && ret + 1 > sizeof(buf)) {
134 		WARN_ONCE(true, "Returned length too big (%d)", ret);
135 		return -E2BIG;
136 	}
137 
138 	if (ret <= size)
139 		memcpy(val, buf, ret);
140 	return ret;
141 }
142 
ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info * ci,char * val,size_t size)143 static ssize_t ceph_vxattrcb_layout_stripe_unit(struct ceph_inode_info *ci,
144 						char *val, size_t size)
145 {
146 	return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_unit);
147 }
148 
ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info * ci,char * val,size_t size)149 static ssize_t ceph_vxattrcb_layout_stripe_count(struct ceph_inode_info *ci,
150 						 char *val, size_t size)
151 {
152 	return ceph_fmt_xattr(val, size, "%u", ci->i_layout.stripe_count);
153 }
154 
ceph_vxattrcb_layout_object_size(struct ceph_inode_info * ci,char * val,size_t size)155 static ssize_t ceph_vxattrcb_layout_object_size(struct ceph_inode_info *ci,
156 						char *val, size_t size)
157 {
158 	return ceph_fmt_xattr(val, size, "%u", ci->i_layout.object_size);
159 }
160 
ceph_vxattrcb_layout_pool(struct ceph_inode_info * ci,char * val,size_t size)161 static ssize_t ceph_vxattrcb_layout_pool(struct ceph_inode_info *ci,
162 					 char *val, size_t size)
163 {
164 	ssize_t ret;
165 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(ci->netfs.inode.i_sb);
166 	struct ceph_osd_client *osdc = &fsc->client->osdc;
167 	s64 pool = ci->i_layout.pool_id;
168 	const char *pool_name;
169 
170 	down_read(&osdc->lock);
171 	pool_name = ceph_pg_pool_name_by_id(osdc->osdmap, pool);
172 	if (pool_name) {
173 		ret = strlen(pool_name);
174 		if (ret <= size)
175 			memcpy(val, pool_name, ret);
176 	} else {
177 		ret = ceph_fmt_xattr(val, size, "%lld", pool);
178 	}
179 	up_read(&osdc->lock);
180 	return ret;
181 }
182 
ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info * ci,char * val,size_t size)183 static ssize_t ceph_vxattrcb_layout_pool_namespace(struct ceph_inode_info *ci,
184 						   char *val, size_t size)
185 {
186 	ssize_t ret = 0;
187 	struct ceph_string *ns = ceph_try_get_string(ci->i_layout.pool_ns);
188 
189 	if (ns) {
190 		ret = ns->len;
191 		if (ret <= size)
192 			memcpy(val, ns->str, ret);
193 		ceph_put_string(ns);
194 	}
195 	return ret;
196 }
197 
198 /* directories */
199 
ceph_vxattrcb_dir_entries(struct ceph_inode_info * ci,char * val,size_t size)200 static ssize_t ceph_vxattrcb_dir_entries(struct ceph_inode_info *ci, char *val,
201 					 size_t size)
202 {
203 	return ceph_fmt_xattr(val, size, "%lld", ci->i_files + ci->i_subdirs);
204 }
205 
ceph_vxattrcb_dir_files(struct ceph_inode_info * ci,char * val,size_t size)206 static ssize_t ceph_vxattrcb_dir_files(struct ceph_inode_info *ci, char *val,
207 				       size_t size)
208 {
209 	return ceph_fmt_xattr(val, size, "%lld", ci->i_files);
210 }
211 
ceph_vxattrcb_dir_subdirs(struct ceph_inode_info * ci,char * val,size_t size)212 static ssize_t ceph_vxattrcb_dir_subdirs(struct ceph_inode_info *ci, char *val,
213 					 size_t size)
214 {
215 	return ceph_fmt_xattr(val, size, "%lld", ci->i_subdirs);
216 }
217 
ceph_vxattrcb_dir_rentries(struct ceph_inode_info * ci,char * val,size_t size)218 static ssize_t ceph_vxattrcb_dir_rentries(struct ceph_inode_info *ci, char *val,
219 					  size_t size)
220 {
221 	return ceph_fmt_xattr(val, size, "%lld",
222 				ci->i_rfiles + ci->i_rsubdirs);
223 }
224 
ceph_vxattrcb_dir_rfiles(struct ceph_inode_info * ci,char * val,size_t size)225 static ssize_t ceph_vxattrcb_dir_rfiles(struct ceph_inode_info *ci, char *val,
226 					size_t size)
227 {
228 	return ceph_fmt_xattr(val, size, "%lld", ci->i_rfiles);
229 }
230 
ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info * ci,char * val,size_t size)231 static ssize_t ceph_vxattrcb_dir_rsubdirs(struct ceph_inode_info *ci, char *val,
232 					  size_t size)
233 {
234 	return ceph_fmt_xattr(val, size, "%lld", ci->i_rsubdirs);
235 }
236 
ceph_vxattrcb_dir_rsnaps(struct ceph_inode_info * ci,char * val,size_t size)237 static ssize_t ceph_vxattrcb_dir_rsnaps(struct ceph_inode_info *ci, char *val,
238 					  size_t size)
239 {
240 	return ceph_fmt_xattr(val, size, "%lld", ci->i_rsnaps);
241 }
242 
ceph_vxattrcb_dir_rbytes(struct ceph_inode_info * ci,char * val,size_t size)243 static ssize_t ceph_vxattrcb_dir_rbytes(struct ceph_inode_info *ci, char *val,
244 					size_t size)
245 {
246 	return ceph_fmt_xattr(val, size, "%lld", ci->i_rbytes);
247 }
248 
ceph_vxattrcb_dir_rctime(struct ceph_inode_info * ci,char * val,size_t size)249 static ssize_t ceph_vxattrcb_dir_rctime(struct ceph_inode_info *ci, char *val,
250 					size_t size)
251 {
252 	return ceph_fmt_xattr(val, size, "%ptSp", &ci->i_rctime);
253 }
254 
255 /* dir pin */
ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info * ci)256 static bool ceph_vxattrcb_dir_pin_exists(struct ceph_inode_info *ci)
257 {
258 	return ci->i_dir_pin != -ENODATA;
259 }
260 
ceph_vxattrcb_dir_pin(struct ceph_inode_info * ci,char * val,size_t size)261 static ssize_t ceph_vxattrcb_dir_pin(struct ceph_inode_info *ci, char *val,
262 				     size_t size)
263 {
264 	return ceph_fmt_xattr(val, size, "%d", (int)ci->i_dir_pin);
265 }
266 
267 /* quotas */
ceph_vxattrcb_quota_exists(struct ceph_inode_info * ci)268 static bool ceph_vxattrcb_quota_exists(struct ceph_inode_info *ci)
269 {
270 	bool ret = false;
271 	spin_lock(&ci->i_ceph_lock);
272 	if ((ci->i_max_files || ci->i_max_bytes) &&
273 	    ci->i_vino.snap == CEPH_NOSNAP &&
274 	    ci->i_snap_realm &&
275 	    ci->i_snap_realm->ino == ci->i_vino.ino)
276 		ret = true;
277 	spin_unlock(&ci->i_ceph_lock);
278 	return ret;
279 }
280 
ceph_vxattrcb_quota(struct ceph_inode_info * ci,char * val,size_t size)281 static ssize_t ceph_vxattrcb_quota(struct ceph_inode_info *ci, char *val,
282 				   size_t size)
283 {
284 	return ceph_fmt_xattr(val, size, "max_bytes=%llu max_files=%llu",
285 				ci->i_max_bytes, ci->i_max_files);
286 }
287 
ceph_vxattrcb_quota_max_bytes(struct ceph_inode_info * ci,char * val,size_t size)288 static ssize_t ceph_vxattrcb_quota_max_bytes(struct ceph_inode_info *ci,
289 					     char *val, size_t size)
290 {
291 	return ceph_fmt_xattr(val, size, "%llu", ci->i_max_bytes);
292 }
293 
ceph_vxattrcb_quota_max_files(struct ceph_inode_info * ci,char * val,size_t size)294 static ssize_t ceph_vxattrcb_quota_max_files(struct ceph_inode_info *ci,
295 					     char *val, size_t size)
296 {
297 	return ceph_fmt_xattr(val, size, "%llu", ci->i_max_files);
298 }
299 
300 /* snapshots */
ceph_vxattrcb_snap_btime_exists(struct ceph_inode_info * ci)301 static bool ceph_vxattrcb_snap_btime_exists(struct ceph_inode_info *ci)
302 {
303 	return (ci->i_snap_btime.tv_sec != 0 || ci->i_snap_btime.tv_nsec != 0);
304 }
305 
ceph_vxattrcb_snap_btime(struct ceph_inode_info * ci,char * val,size_t size)306 static ssize_t ceph_vxattrcb_snap_btime(struct ceph_inode_info *ci, char *val,
307 					size_t size)
308 {
309 	return ceph_fmt_xattr(val, size, "%ptSp", &ci->i_snap_btime);
310 }
311 
ceph_vxattrcb_cluster_fsid(struct ceph_inode_info * ci,char * val,size_t size)312 static ssize_t ceph_vxattrcb_cluster_fsid(struct ceph_inode_info *ci,
313 					  char *val, size_t size)
314 {
315 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(ci->netfs.inode.i_sb);
316 
317 	return ceph_fmt_xattr(val, size, "%pU", &fsc->client->fsid);
318 }
319 
ceph_vxattrcb_client_id(struct ceph_inode_info * ci,char * val,size_t size)320 static ssize_t ceph_vxattrcb_client_id(struct ceph_inode_info *ci,
321 				       char *val, size_t size)
322 {
323 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(ci->netfs.inode.i_sb);
324 
325 	return ceph_fmt_xattr(val, size, "client%lld",
326 			      ceph_client_gid(fsc->client));
327 }
328 
ceph_vxattrcb_caps(struct ceph_inode_info * ci,char * val,size_t size)329 static ssize_t ceph_vxattrcb_caps(struct ceph_inode_info *ci, char *val,
330 					size_t size)
331 {
332 	int issued;
333 
334 	spin_lock(&ci->i_ceph_lock);
335 	issued = __ceph_caps_issued(ci, NULL);
336 	spin_unlock(&ci->i_ceph_lock);
337 
338 	return ceph_fmt_xattr(val, size, "%s/0x%x",
339 			      ceph_cap_string(issued), issued);
340 }
341 
ceph_vxattrcb_auth_mds(struct ceph_inode_info * ci,char * val,size_t size)342 static ssize_t ceph_vxattrcb_auth_mds(struct ceph_inode_info *ci,
343 				       char *val, size_t size)
344 {
345 	int ret;
346 
347 	spin_lock(&ci->i_ceph_lock);
348 	ret = ceph_fmt_xattr(val, size, "%d",
349 			     ci->i_auth_cap ? ci->i_auth_cap->session->s_mds : -1);
350 	spin_unlock(&ci->i_ceph_lock);
351 	return ret;
352 }
353 
354 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
ceph_vxattrcb_fscrypt_auth_exists(struct ceph_inode_info * ci)355 static bool ceph_vxattrcb_fscrypt_auth_exists(struct ceph_inode_info *ci)
356 {
357 	return ci->fscrypt_auth_len;
358 }
359 
ceph_vxattrcb_fscrypt_auth(struct ceph_inode_info * ci,char * val,size_t size)360 static ssize_t ceph_vxattrcb_fscrypt_auth(struct ceph_inode_info *ci,
361 					  char *val, size_t size)
362 {
363 	if (size) {
364 		if (size < ci->fscrypt_auth_len)
365 			return -ERANGE;
366 		memcpy(val, ci->fscrypt_auth, ci->fscrypt_auth_len);
367 	}
368 	return ci->fscrypt_auth_len;
369 }
370 #endif /* CONFIG_FS_ENCRYPTION */
371 
372 #define CEPH_XATTR_NAME(_type, _name)	XATTR_CEPH_PREFIX #_type "." #_name
373 #define CEPH_XATTR_NAME2(_type, _name, _name2)	\
374 	XATTR_CEPH_PREFIX #_type "." #_name "." #_name2
375 
376 #define XATTR_NAME_CEPH(_type, _name, _flags)				\
377 	{								\
378 		.name = CEPH_XATTR_NAME(_type, _name),			\
379 		.name_size = sizeof (CEPH_XATTR_NAME(_type, _name)), \
380 		.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name, \
381 		.exists_cb = NULL,					\
382 		.flags = (VXATTR_FLAG_READONLY | _flags),		\
383 	}
384 #define XATTR_RSTAT_FIELD(_type, _name)			\
385 	XATTR_NAME_CEPH(_type, _name, VXATTR_FLAG_RSTAT)
386 #define XATTR_RSTAT_FIELD_UPDATABLE(_type, _name)			\
387 	{								\
388 		.name = CEPH_XATTR_NAME(_type, _name),			\
389 		.name_size = sizeof (CEPH_XATTR_NAME(_type, _name)),	\
390 		.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name,	\
391 		.exists_cb = NULL,					\
392 		.flags = VXATTR_FLAG_RSTAT,				\
393 	}
394 #define XATTR_LAYOUT_FIELD(_type, _name, _field)			\
395 	{								\
396 		.name = CEPH_XATTR_NAME2(_type, _name, _field),	\
397 		.name_size = sizeof (CEPH_XATTR_NAME2(_type, _name, _field)), \
398 		.getxattr_cb = ceph_vxattrcb_ ## _name ## _ ## _field, \
399 		.exists_cb = ceph_vxattrcb_layout_exists,	\
400 		.flags = VXATTR_FLAG_HIDDEN,			\
401 	}
402 #define XATTR_QUOTA_FIELD(_type, _name)					\
403 	{								\
404 		.name = CEPH_XATTR_NAME(_type, _name),			\
405 		.name_size = sizeof(CEPH_XATTR_NAME(_type, _name)),	\
406 		.getxattr_cb = ceph_vxattrcb_ ## _type ## _ ## _name,	\
407 		.exists_cb = ceph_vxattrcb_quota_exists,		\
408 		.flags = VXATTR_FLAG_HIDDEN,				\
409 	}
410 
411 static struct ceph_vxattr ceph_dir_vxattrs[] = {
412 	{
413 		.name = "ceph.dir.layout",
414 		.name_size = sizeof("ceph.dir.layout"),
415 		.getxattr_cb = ceph_vxattrcb_layout,
416 		.exists_cb = ceph_vxattrcb_layout_exists,
417 		.flags = VXATTR_FLAG_HIDDEN,
418 	},
419 	XATTR_LAYOUT_FIELD(dir, layout, stripe_unit),
420 	XATTR_LAYOUT_FIELD(dir, layout, stripe_count),
421 	XATTR_LAYOUT_FIELD(dir, layout, object_size),
422 	XATTR_LAYOUT_FIELD(dir, layout, pool),
423 	XATTR_LAYOUT_FIELD(dir, layout, pool_namespace),
424 	XATTR_NAME_CEPH(dir, entries, VXATTR_FLAG_DIRSTAT),
425 	XATTR_NAME_CEPH(dir, files, VXATTR_FLAG_DIRSTAT),
426 	XATTR_NAME_CEPH(dir, subdirs, VXATTR_FLAG_DIRSTAT),
427 	XATTR_RSTAT_FIELD(dir, rentries),
428 	XATTR_RSTAT_FIELD(dir, rfiles),
429 	XATTR_RSTAT_FIELD(dir, rsubdirs),
430 	XATTR_RSTAT_FIELD(dir, rsnaps),
431 	XATTR_RSTAT_FIELD(dir, rbytes),
432 	XATTR_RSTAT_FIELD_UPDATABLE(dir, rctime),
433 	{
434 		.name = "ceph.dir.pin",
435 		.name_size = sizeof("ceph.dir.pin"),
436 		.getxattr_cb = ceph_vxattrcb_dir_pin,
437 		.exists_cb = ceph_vxattrcb_dir_pin_exists,
438 		.flags = VXATTR_FLAG_HIDDEN,
439 	},
440 	{
441 		.name = "ceph.quota",
442 		.name_size = sizeof("ceph.quota"),
443 		.getxattr_cb = ceph_vxattrcb_quota,
444 		.exists_cb = ceph_vxattrcb_quota_exists,
445 		.flags = VXATTR_FLAG_HIDDEN,
446 	},
447 	XATTR_QUOTA_FIELD(quota, max_bytes),
448 	XATTR_QUOTA_FIELD(quota, max_files),
449 	{
450 		.name = "ceph.snap.btime",
451 		.name_size = sizeof("ceph.snap.btime"),
452 		.getxattr_cb = ceph_vxattrcb_snap_btime,
453 		.exists_cb = ceph_vxattrcb_snap_btime_exists,
454 		.flags = VXATTR_FLAG_READONLY,
455 	},
456 	{
457 		.name = "ceph.caps",
458 		.name_size = sizeof("ceph.caps"),
459 		.getxattr_cb = ceph_vxattrcb_caps,
460 		.exists_cb = NULL,
461 		.flags = VXATTR_FLAG_HIDDEN,
462 	},
463 	{ .name = NULL, 0 }	/* Required table terminator */
464 };
465 
466 /* files */
467 
468 static struct ceph_vxattr ceph_file_vxattrs[] = {
469 	{
470 		.name = "ceph.file.layout",
471 		.name_size = sizeof("ceph.file.layout"),
472 		.getxattr_cb = ceph_vxattrcb_layout,
473 		.exists_cb = ceph_vxattrcb_layout_exists,
474 		.flags = VXATTR_FLAG_HIDDEN,
475 	},
476 	XATTR_LAYOUT_FIELD(file, layout, stripe_unit),
477 	XATTR_LAYOUT_FIELD(file, layout, stripe_count),
478 	XATTR_LAYOUT_FIELD(file, layout, object_size),
479 	XATTR_LAYOUT_FIELD(file, layout, pool),
480 	XATTR_LAYOUT_FIELD(file, layout, pool_namespace),
481 	{
482 		.name = "ceph.snap.btime",
483 		.name_size = sizeof("ceph.snap.btime"),
484 		.getxattr_cb = ceph_vxattrcb_snap_btime,
485 		.exists_cb = ceph_vxattrcb_snap_btime_exists,
486 		.flags = VXATTR_FLAG_READONLY,
487 	},
488 	{
489 		.name = "ceph.caps",
490 		.name_size = sizeof("ceph.caps"),
491 		.getxattr_cb = ceph_vxattrcb_caps,
492 		.exists_cb = NULL,
493 		.flags = VXATTR_FLAG_HIDDEN,
494 	},
495 	{ .name = NULL, 0 }	/* Required table terminator */
496 };
497 
498 static struct ceph_vxattr ceph_common_vxattrs[] = {
499 	{
500 		.name = "ceph.cluster_fsid",
501 		.name_size = sizeof("ceph.cluster_fsid"),
502 		.getxattr_cb = ceph_vxattrcb_cluster_fsid,
503 		.exists_cb = NULL,
504 		.flags = VXATTR_FLAG_READONLY,
505 	},
506 	{
507 		.name = "ceph.client_id",
508 		.name_size = sizeof("ceph.client_id"),
509 		.getxattr_cb = ceph_vxattrcb_client_id,
510 		.exists_cb = NULL,
511 		.flags = VXATTR_FLAG_READONLY,
512 	},
513 	{
514 		.name = "ceph.auth_mds",
515 		.name_size = sizeof("ceph.auth_mds"),
516 		.getxattr_cb = ceph_vxattrcb_auth_mds,
517 		.exists_cb = NULL,
518 		.flags = VXATTR_FLAG_READONLY,
519 	},
520 #if IS_ENABLED(CONFIG_FS_ENCRYPTION)
521 	{
522 		.name = "ceph.fscrypt.auth",
523 		.name_size = sizeof("ceph.fscrypt.auth"),
524 		.getxattr_cb = ceph_vxattrcb_fscrypt_auth,
525 		.exists_cb = ceph_vxattrcb_fscrypt_auth_exists,
526 		.flags = VXATTR_FLAG_READONLY,
527 	},
528 #endif /* CONFIG_FS_ENCRYPTION */
529 	{ .name = NULL, 0 }	/* Required table terminator */
530 };
531 
ceph_inode_vxattrs(struct inode * inode)532 static struct ceph_vxattr *ceph_inode_vxattrs(struct inode *inode)
533 {
534 	if (S_ISDIR(inode->i_mode))
535 		return ceph_dir_vxattrs;
536 	else if (S_ISREG(inode->i_mode))
537 		return ceph_file_vxattrs;
538 	return NULL;
539 }
540 
ceph_match_vxattr(struct inode * inode,const char * name)541 static struct ceph_vxattr *ceph_match_vxattr(struct inode *inode,
542 						const char *name)
543 {
544 	struct ceph_vxattr *vxattr = ceph_inode_vxattrs(inode);
545 
546 	if (vxattr) {
547 		while (vxattr->name) {
548 			if (!strcmp(vxattr->name, name))
549 				return vxattr;
550 			vxattr++;
551 		}
552 	}
553 
554 	vxattr = ceph_common_vxattrs;
555 	while (vxattr->name) {
556 		if (!strcmp(vxattr->name, name))
557 			return vxattr;
558 		vxattr++;
559 	}
560 
561 	return NULL;
562 }
563 
564 #define MAX_XATTR_VAL_PRINT_LEN 256
565 
__set_xattr(struct ceph_inode_info * ci,const char * name,int name_len,const char * val,int val_len,int flags,int update_xattr,struct ceph_inode_xattr ** newxattr)566 static int __set_xattr(struct ceph_inode_info *ci,
567 			   const char *name, int name_len,
568 			   const char *val, int val_len,
569 			   int flags, int update_xattr,
570 			   struct ceph_inode_xattr **newxattr)
571 {
572 	struct inode *inode = &ci->netfs.inode;
573 	struct ceph_client *cl = ceph_inode_to_client(inode);
574 	struct rb_node **p;
575 	struct rb_node *parent = NULL;
576 	struct ceph_inode_xattr *xattr = NULL;
577 	int c;
578 	int new = 0;
579 
580 	p = &ci->i_xattrs.index.rb_node;
581 	while (*p) {
582 		parent = *p;
583 		xattr = rb_entry(parent, struct ceph_inode_xattr, node);
584 		c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
585 		if (c < 0)
586 			p = &(*p)->rb_left;
587 		else if (c > 0)
588 			p = &(*p)->rb_right;
589 		else {
590 			if (name_len == xattr->name_len)
591 				break;
592 			else if (name_len < xattr->name_len)
593 				p = &(*p)->rb_left;
594 			else
595 				p = &(*p)->rb_right;
596 		}
597 		xattr = NULL;
598 	}
599 
600 	if (update_xattr) {
601 		int err = 0;
602 
603 		if (xattr && (flags & XATTR_CREATE))
604 			err = -EEXIST;
605 		else if (!xattr && (flags & XATTR_REPLACE))
606 			err = -ENODATA;
607 		if (err) {
608 			kfree(name);
609 			kfree(val);
610 			kfree(*newxattr);
611 			return err;
612 		}
613 		if (update_xattr < 0) {
614 			if (xattr)
615 				__remove_xattr(ci, xattr);
616 			kfree(name);
617 			kfree(*newxattr);
618 			return 0;
619 		}
620 	}
621 
622 	if (!xattr) {
623 		new = 1;
624 		xattr = *newxattr;
625 		xattr->name = name;
626 		xattr->name_len = name_len;
627 		xattr->should_free_name = update_xattr;
628 
629 		ci->i_xattrs.count++;
630 		doutc(cl, "count=%d\n", ci->i_xattrs.count);
631 	} else {
632 		kfree(*newxattr);
633 		*newxattr = NULL;
634 		if (xattr->should_free_val)
635 			kfree(xattr->val);
636 
637 		if (update_xattr) {
638 			kfree(name);
639 			name = xattr->name;
640 		}
641 		ci->i_xattrs.names_size -= xattr->name_len;
642 		ci->i_xattrs.vals_size -= xattr->val_len;
643 	}
644 	ci->i_xattrs.names_size += name_len;
645 	ci->i_xattrs.vals_size += val_len;
646 	if (val)
647 		xattr->val = val;
648 	else
649 		xattr->val = "";
650 
651 	xattr->val_len = val_len;
652 	xattr->dirty = update_xattr;
653 	xattr->should_free_val = (val && update_xattr);
654 
655 	if (new) {
656 		rb_link_node(&xattr->node, parent, p);
657 		rb_insert_color(&xattr->node, &ci->i_xattrs.index);
658 		doutc(cl, "p=%p\n", p);
659 	}
660 
661 	doutc(cl, "added %p %llx.%llx xattr %p %.*s=%.*s%s\n", inode,
662 	      ceph_vinop(inode), xattr, name_len, name, min(val_len,
663 	      MAX_XATTR_VAL_PRINT_LEN), val,
664 	      val_len > MAX_XATTR_VAL_PRINT_LEN ? "..." : "");
665 
666 	return 0;
667 }
668 
__get_xattr(struct ceph_inode_info * ci,const char * name)669 static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
670 			   const char *name)
671 {
672 	struct ceph_client *cl = ceph_inode_to_client(&ci->netfs.inode);
673 	struct rb_node **p;
674 	struct rb_node *parent = NULL;
675 	struct ceph_inode_xattr *xattr = NULL;
676 	int name_len = strlen(name);
677 	int c;
678 
679 	p = &ci->i_xattrs.index.rb_node;
680 	while (*p) {
681 		parent = *p;
682 		xattr = rb_entry(parent, struct ceph_inode_xattr, node);
683 		c = strncmp(name, xattr->name, xattr->name_len);
684 		if (c == 0 && name_len > xattr->name_len)
685 			c = 1;
686 		if (c < 0)
687 			p = &(*p)->rb_left;
688 		else if (c > 0)
689 			p = &(*p)->rb_right;
690 		else {
691 			int len = min(xattr->val_len, MAX_XATTR_VAL_PRINT_LEN);
692 
693 			doutc(cl, "%s found %.*s%s\n", name, len, xattr->val,
694 			      xattr->val_len > len ? "..." : "");
695 			return xattr;
696 		}
697 	}
698 
699 	doutc(cl, "%s not found\n", name);
700 
701 	return NULL;
702 }
703 
__free_xattr(struct ceph_inode_xattr * xattr)704 static void __free_xattr(struct ceph_inode_xattr *xattr)
705 {
706 	BUG_ON(!xattr);
707 
708 	if (xattr->should_free_name)
709 		kfree(xattr->name);
710 	if (xattr->should_free_val)
711 		kfree(xattr->val);
712 
713 	kfree(xattr);
714 }
715 
__remove_xattr(struct ceph_inode_info * ci,struct ceph_inode_xattr * xattr)716 static int __remove_xattr(struct ceph_inode_info *ci,
717 			  struct ceph_inode_xattr *xattr)
718 {
719 	if (!xattr)
720 		return -ENODATA;
721 
722 	rb_erase(&xattr->node, &ci->i_xattrs.index);
723 
724 	if (xattr->should_free_name)
725 		kfree(xattr->name);
726 	if (xattr->should_free_val)
727 		kfree(xattr->val);
728 
729 	ci->i_xattrs.names_size -= xattr->name_len;
730 	ci->i_xattrs.vals_size -= xattr->val_len;
731 	ci->i_xattrs.count--;
732 	kfree(xattr);
733 
734 	return 0;
735 }
736 
__copy_xattr_names(struct ceph_inode_info * ci,char * dest)737 static char *__copy_xattr_names(struct ceph_inode_info *ci,
738 				char *dest)
739 {
740 	struct ceph_client *cl = ceph_inode_to_client(&ci->netfs.inode);
741 	struct rb_node *p;
742 	struct ceph_inode_xattr *xattr = NULL;
743 
744 	p = rb_first(&ci->i_xattrs.index);
745 	doutc(cl, "count=%d\n", ci->i_xattrs.count);
746 
747 	while (p) {
748 		xattr = rb_entry(p, struct ceph_inode_xattr, node);
749 		memcpy(dest, xattr->name, xattr->name_len);
750 		dest[xattr->name_len] = '\0';
751 
752 		doutc(cl, "dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
753 		      xattr->name_len, ci->i_xattrs.names_size);
754 
755 		dest += xattr->name_len + 1;
756 		p = rb_next(p);
757 	}
758 
759 	return dest;
760 }
761 
__ceph_destroy_xattrs(struct ceph_inode_info * ci)762 void __ceph_destroy_xattrs(struct ceph_inode_info *ci)
763 {
764 	struct ceph_client *cl = ceph_inode_to_client(&ci->netfs.inode);
765 	struct rb_node *p, *tmp;
766 	struct ceph_inode_xattr *xattr = NULL;
767 
768 	p = rb_first(&ci->i_xattrs.index);
769 
770 	doutc(cl, "p=%p\n", p);
771 
772 	while (p) {
773 		xattr = rb_entry(p, struct ceph_inode_xattr, node);
774 		tmp = p;
775 		p = rb_next(tmp);
776 		doutc(cl, "next p=%p (%.*s)\n", p, xattr->name_len, xattr->name);
777 		rb_erase(tmp, &ci->i_xattrs.index);
778 
779 		__free_xattr(xattr);
780 	}
781 
782 	ci->i_xattrs.names_size = 0;
783 	ci->i_xattrs.vals_size = 0;
784 	ci->i_xattrs.index_version = 0;
785 	ci->i_xattrs.count = 0;
786 	ci->i_xattrs.index = RB_ROOT;
787 }
788 
__build_xattrs(struct inode * inode)789 static int __build_xattrs(struct inode *inode)
790 	__releases(ci->i_ceph_lock)
791 	__acquires(ci->i_ceph_lock)
792 {
793 	struct ceph_client *cl = ceph_inode_to_client(inode);
794 	u32 namelen;
795 	u32 numattr = 0;
796 	void *p, *end;
797 	u32 len;
798 	const char *name, *val;
799 	struct ceph_inode_info *ci = ceph_inode(inode);
800 	u64 xattr_version;
801 	struct ceph_inode_xattr **xattrs = NULL;
802 	int err = 0;
803 	int i;
804 
805 	doutc(cl, "len=%d\n",
806 	      ci->i_xattrs.blob ? (int)ci->i_xattrs.blob->vec.iov_len : 0);
807 
808 	if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
809 		return 0; /* already built */
810 
811 	__ceph_destroy_xattrs(ci);
812 
813 start:
814 	/* updated internal xattr rb tree */
815 	if (ci->i_xattrs.blob && ci->i_xattrs.blob->vec.iov_len > 4) {
816 		p = ci->i_xattrs.blob->vec.iov_base;
817 		end = p + ci->i_xattrs.blob->vec.iov_len;
818 		ceph_decode_32_safe(&p, end, numattr, bad);
819 		xattr_version = ci->i_xattrs.version;
820 		spin_unlock(&ci->i_ceph_lock);
821 
822 		xattrs = kzalloc_objs(struct ceph_inode_xattr *, numattr,
823 				      GFP_NOFS);
824 		err = -ENOMEM;
825 		if (!xattrs)
826 			goto bad_lock;
827 
828 		for (i = 0; i < numattr; i++) {
829 			xattrs[i] = kmalloc_obj(struct ceph_inode_xattr,
830 						GFP_NOFS);
831 			if (!xattrs[i])
832 				goto bad_lock;
833 		}
834 
835 		spin_lock(&ci->i_ceph_lock);
836 		if (ci->i_xattrs.version != xattr_version) {
837 			/* lost a race, retry */
838 			for (i = 0; i < numattr; i++)
839 				kfree(xattrs[i]);
840 			kfree(xattrs);
841 			xattrs = NULL;
842 			goto start;
843 		}
844 		err = -EIO;
845 		while (numattr--) {
846 			ceph_decode_32_safe(&p, end, len, bad);
847 			namelen = len;
848 			name = p;
849 			p += len;
850 			ceph_decode_32_safe(&p, end, len, bad);
851 			ceph_decode_need(&p, end, len, bad);
852 			val = p;
853 			p += len;
854 
855 			err = __set_xattr(ci, name, namelen, val, len,
856 					  0, 0, &xattrs[numattr]);
857 
858 			if (err < 0)
859 				goto bad;
860 		}
861 		kfree(xattrs);
862 	}
863 	ci->i_xattrs.index_version = ci->i_xattrs.version;
864 	ci->i_xattrs.dirty = false;
865 
866 	return err;
867 bad_lock:
868 	spin_lock(&ci->i_ceph_lock);
869 bad:
870 	if (xattrs) {
871 		for (i = 0; i < numattr; i++)
872 			kfree(xattrs[i]);
873 		kfree(xattrs);
874 	}
875 	ci->i_xattrs.names_size = 0;
876 	return err;
877 }
878 
__get_required_blob_size(struct ceph_inode_info * ci,int name_size,int val_size)879 static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
880 				    int val_size)
881 {
882 	struct ceph_client *cl = ceph_inode_to_client(&ci->netfs.inode);
883 
884 	/*
885 	 * 4 bytes for the length, and additional 4 bytes per each xattr name,
886 	 * 4 bytes per each value
887 	 */
888 	int size = 4 + ci->i_xattrs.count*(4 + 4) +
889 			     ci->i_xattrs.names_size +
890 			     ci->i_xattrs.vals_size;
891 	doutc(cl, "c=%d names.size=%d vals.size=%d\n", ci->i_xattrs.count,
892 	      ci->i_xattrs.names_size, ci->i_xattrs.vals_size);
893 
894 	if (name_size)
895 		size += 4 + 4 + name_size + val_size;
896 
897 	return size;
898 }
899 
900 /*
901  * If there are dirty xattrs, re-encode xattrs into the prealloc_blob
902  * and swap into place.  It returns the old i_xattrs.blob (or NULL) so
903  * that it can be freed by the caller as the i_ceph_lock is likely to be
904  * held.
905  */
__ceph_build_xattrs_blob(struct ceph_inode_info * ci)906 struct ceph_buffer *__ceph_build_xattrs_blob(struct ceph_inode_info *ci)
907 {
908 	struct inode *inode = &ci->netfs.inode;
909 	struct ceph_client *cl = ceph_inode_to_client(inode);
910 	struct rb_node *p;
911 	struct ceph_inode_xattr *xattr = NULL;
912 	struct ceph_buffer *old_blob = NULL;
913 	void *dest;
914 
915 	doutc(cl, "%p %llx.%llx\n", inode, ceph_vinop(inode));
916 	if (ci->i_xattrs.dirty) {
917 		int need = __get_required_blob_size(ci, 0, 0);
918 
919 		BUG_ON(need > ci->i_xattrs.prealloc_blob->alloc_len);
920 
921 		p = rb_first(&ci->i_xattrs.index);
922 		dest = ci->i_xattrs.prealloc_blob->vec.iov_base;
923 
924 		ceph_encode_32(&dest, ci->i_xattrs.count);
925 		while (p) {
926 			xattr = rb_entry(p, struct ceph_inode_xattr, node);
927 
928 			ceph_encode_32(&dest, xattr->name_len);
929 			memcpy(dest, xattr->name, xattr->name_len);
930 			dest += xattr->name_len;
931 			ceph_encode_32(&dest, xattr->val_len);
932 			memcpy(dest, xattr->val, xattr->val_len);
933 			dest += xattr->val_len;
934 
935 			p = rb_next(p);
936 		}
937 
938 		/* adjust buffer len; it may be larger than we need */
939 		ci->i_xattrs.prealloc_blob->vec.iov_len =
940 			dest - ci->i_xattrs.prealloc_blob->vec.iov_base;
941 
942 		if (ci->i_xattrs.blob)
943 			old_blob = ci->i_xattrs.blob;
944 		ci->i_xattrs.blob = ci->i_xattrs.prealloc_blob;
945 		ci->i_xattrs.prealloc_blob = NULL;
946 		ci->i_xattrs.dirty = false;
947 		ci->i_xattrs.version++;
948 	}
949 
950 	return old_blob;
951 }
952 
__get_request_mask(struct inode * in)953 static inline int __get_request_mask(struct inode *in) {
954 	struct ceph_mds_request *req = current->journal_info;
955 	int mask = 0;
956 	if (req && req->r_target_inode == in) {
957 		if (req->r_op == CEPH_MDS_OP_LOOKUP ||
958 		    req->r_op == CEPH_MDS_OP_LOOKUPINO ||
959 		    req->r_op == CEPH_MDS_OP_LOOKUPPARENT ||
960 		    req->r_op == CEPH_MDS_OP_GETATTR) {
961 			mask = le32_to_cpu(req->r_args.getattr.mask);
962 		} else if (req->r_op == CEPH_MDS_OP_OPEN ||
963 			   req->r_op == CEPH_MDS_OP_CREATE) {
964 			mask = le32_to_cpu(req->r_args.open.mask);
965 		}
966 	}
967 	return mask;
968 }
969 
__ceph_getxattr(struct inode * inode,const char * name,void * value,size_t size)970 ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
971 		      size_t size)
972 {
973 	struct ceph_client *cl = ceph_inode_to_client(inode);
974 	struct ceph_inode_info *ci = ceph_inode(inode);
975 	struct ceph_inode_xattr *xattr;
976 	struct ceph_vxattr *vxattr;
977 	int req_mask;
978 	ssize_t err;
979 
980 	if (strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
981 		goto handle_non_vxattrs;
982 
983 	/* let's see if a virtual xattr was requested */
984 	vxattr = ceph_match_vxattr(inode, name);
985 	if (vxattr) {
986 		int mask = 0;
987 		if (vxattr->flags & VXATTR_FLAG_RSTAT)
988 			mask |= CEPH_STAT_RSTAT;
989 		if (vxattr->flags & VXATTR_FLAG_DIRSTAT)
990 			mask |= CEPH_CAP_FILE_SHARED;
991 		err = ceph_do_getattr(inode, mask, true);
992 		if (err)
993 			return err;
994 		err = -ENODATA;
995 		if (!(vxattr->exists_cb && !vxattr->exists_cb(ci))) {
996 			err = vxattr->getxattr_cb(ci, value, size);
997 			if (size && size < err)
998 				err = -ERANGE;
999 		}
1000 		return err;
1001 	} else {
1002 		err = ceph_do_getvxattr(inode, name, value, size);
1003 		/* this would happen with a new client and old server combo */
1004 		if (err == -EOPNOTSUPP)
1005 			err = -ENODATA;
1006 		return err;
1007 	}
1008 handle_non_vxattrs:
1009 	req_mask = __get_request_mask(inode);
1010 
1011 	spin_lock(&ci->i_ceph_lock);
1012 	doutc(cl, "%p %llx.%llx name '%s' ver=%lld index_ver=%lld\n", inode,
1013 	      ceph_vinop(inode), name, ci->i_xattrs.version,
1014 	      ci->i_xattrs.index_version);
1015 
1016 	if (ci->i_xattrs.version == 0 ||
1017 	    !((req_mask & CEPH_CAP_XATTR_SHARED) ||
1018 	      __ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1))) {
1019 		spin_unlock(&ci->i_ceph_lock);
1020 
1021 		/* security module gets xattr while filling trace */
1022 		if (current->journal_info) {
1023 			pr_warn_ratelimited_client(cl,
1024 				"sync %p %llx.%llx during filling trace\n",
1025 				inode, ceph_vinop(inode));
1026 			return -EBUSY;
1027 		}
1028 
1029 		/* get xattrs from mds (if we don't already have them) */
1030 		err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
1031 		if (err)
1032 			return err;
1033 		spin_lock(&ci->i_ceph_lock);
1034 	}
1035 
1036 	err = __build_xattrs(inode);
1037 	if (err < 0)
1038 		goto out;
1039 
1040 	err = -ENODATA;  /* == ENOATTR */
1041 	xattr = __get_xattr(ci, name);
1042 	if (!xattr)
1043 		goto out;
1044 
1045 	err = -ERANGE;
1046 	if (size && size < xattr->val_len)
1047 		goto out;
1048 
1049 	err = xattr->val_len;
1050 	if (size == 0)
1051 		goto out;
1052 
1053 	memcpy(value, xattr->val, xattr->val_len);
1054 
1055 	if (current->journal_info &&
1056 	    !strncmp(name, XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) &&
1057 	    security_ismaclabel(name + XATTR_SECURITY_PREFIX_LEN))
1058 		set_bit(CEPH_I_SEC_INITED_BIT, &ci->i_ceph_flags);
1059 out:
1060 	spin_unlock(&ci->i_ceph_lock);
1061 	return err;
1062 }
1063 
ceph_listxattr(struct dentry * dentry,char * names,size_t size)1064 ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
1065 {
1066 	struct inode *inode = d_inode(dentry);
1067 	struct ceph_client *cl = ceph_inode_to_client(inode);
1068 	struct ceph_inode_info *ci = ceph_inode(inode);
1069 	bool len_only = (size == 0);
1070 	u32 namelen;
1071 	int err;
1072 
1073 	spin_lock(&ci->i_ceph_lock);
1074 	doutc(cl, "%p %llx.%llx ver=%lld index_ver=%lld\n", inode,
1075 	      ceph_vinop(inode), ci->i_xattrs.version,
1076 	      ci->i_xattrs.index_version);
1077 
1078 	if (ci->i_xattrs.version == 0 ||
1079 	    !__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1)) {
1080 		spin_unlock(&ci->i_ceph_lock);
1081 		err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
1082 		if (err)
1083 			return err;
1084 		spin_lock(&ci->i_ceph_lock);
1085 	}
1086 
1087 	err = __build_xattrs(inode);
1088 	if (err < 0)
1089 		goto out;
1090 
1091 	/* add 1 byte for each xattr due to the null termination */
1092 	namelen = ci->i_xattrs.names_size + ci->i_xattrs.count;
1093 	if (!len_only) {
1094 		if (namelen > size) {
1095 			err = -ERANGE;
1096 			goto out;
1097 		}
1098 		names = __copy_xattr_names(ci, names);
1099 		size -= namelen;
1100 	}
1101 	err = namelen;
1102 out:
1103 	spin_unlock(&ci->i_ceph_lock);
1104 	return err;
1105 }
1106 
ceph_sync_setxattr(struct inode * inode,const char * name,const char * value,size_t size,int flags)1107 static int ceph_sync_setxattr(struct inode *inode, const char *name,
1108 			      const char *value, size_t size, int flags)
1109 {
1110 	struct ceph_fs_client *fsc = ceph_sb_to_fs_client(inode->i_sb);
1111 	struct ceph_client *cl = ceph_inode_to_client(inode);
1112 	struct ceph_inode_info *ci = ceph_inode(inode);
1113 	struct ceph_mds_request *req;
1114 	struct ceph_mds_client *mdsc = fsc->mdsc;
1115 	struct ceph_osd_client *osdc = &fsc->client->osdc;
1116 	struct ceph_pagelist *pagelist = NULL;
1117 	int op = CEPH_MDS_OP_SETXATTR;
1118 	int err;
1119 
1120 	if (size > 0) {
1121 		/* copy value into pagelist */
1122 		pagelist = ceph_pagelist_alloc(GFP_NOFS);
1123 		if (!pagelist)
1124 			return -ENOMEM;
1125 
1126 		err = ceph_pagelist_append(pagelist, value, size);
1127 		if (err)
1128 			goto out;
1129 	} else if (!value) {
1130 		if (flags & CEPH_XATTR_REPLACE)
1131 			op = CEPH_MDS_OP_RMXATTR;
1132 		else
1133 			flags |= CEPH_XATTR_REMOVE;
1134 	}
1135 
1136 	doutc(cl, "name %s value size %zu\n", name, size);
1137 
1138 	/* do request */
1139 	req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
1140 	if (IS_ERR(req)) {
1141 		err = PTR_ERR(req);
1142 		goto out;
1143 	}
1144 
1145 	req->r_path2 = kstrdup(name, GFP_NOFS);
1146 	if (!req->r_path2) {
1147 		ceph_mdsc_put_request(req);
1148 		err = -ENOMEM;
1149 		goto out;
1150 	}
1151 
1152 	if (op == CEPH_MDS_OP_SETXATTR) {
1153 		req->r_args.setxattr.flags = cpu_to_le32(flags);
1154 		req->r_args.setxattr.osdmap_epoch =
1155 			cpu_to_le32(osdc->osdmap->epoch);
1156 		req->r_pagelist = pagelist;
1157 		pagelist = NULL;
1158 	}
1159 
1160 	req->r_inode = inode;
1161 	ihold(inode);
1162 	req->r_num_caps = 1;
1163 	req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
1164 
1165 	doutc(cl, "xattr.ver (before): %lld\n", ci->i_xattrs.version);
1166 	err = ceph_mdsc_do_request(mdsc, NULL, req);
1167 	ceph_mdsc_put_request(req);
1168 	doutc(cl, "xattr.ver (after): %lld\n", ci->i_xattrs.version);
1169 
1170 out:
1171 	if (pagelist)
1172 		ceph_pagelist_release(pagelist);
1173 	return err;
1174 }
1175 
__ceph_setxattr(struct inode * inode,const char * name,const void * value,size_t size,int flags)1176 int __ceph_setxattr(struct inode *inode, const char *name,
1177 			const void *value, size_t size, int flags)
1178 {
1179 	struct ceph_client *cl = ceph_inode_to_client(inode);
1180 	struct ceph_vxattr *vxattr;
1181 	struct ceph_inode_info *ci = ceph_inode(inode);
1182 	struct ceph_mds_client *mdsc = ceph_sb_to_fs_client(inode->i_sb)->mdsc;
1183 	struct ceph_cap_flush *prealloc_cf = NULL;
1184 	struct ceph_buffer *old_blob = NULL;
1185 	int issued;
1186 	int err;
1187 	int dirty = 0;
1188 	int name_len = strlen(name);
1189 	int val_len = size;
1190 	char *newname = NULL;
1191 	char *newval = NULL;
1192 	struct ceph_inode_xattr *xattr = NULL;
1193 	int required_blob_size;
1194 	bool check_realm = false;
1195 	bool lock_snap_rwsem = false;
1196 
1197 	if (ceph_snap(inode) != CEPH_NOSNAP)
1198 		return -EROFS;
1199 
1200 	vxattr = ceph_match_vxattr(inode, name);
1201 	if (vxattr) {
1202 		if (vxattr->flags & VXATTR_FLAG_READONLY)
1203 			return -EOPNOTSUPP;
1204 		if (value && !strncmp(vxattr->name, "ceph.quota", 10))
1205 			check_realm = true;
1206 	}
1207 
1208 	/* pass any unhandled ceph.* xattrs through to the MDS */
1209 	if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
1210 		goto do_sync_unlocked;
1211 
1212 	/* preallocate memory for xattr name, value, index node */
1213 	err = -ENOMEM;
1214 	newname = kmemdup(name, name_len + 1, GFP_NOFS);
1215 	if (!newname)
1216 		goto out;
1217 
1218 	if (val_len) {
1219 		newval = kmemdup(value, val_len, GFP_NOFS);
1220 		if (!newval)
1221 			goto out;
1222 	}
1223 
1224 	xattr = kmalloc_obj(struct ceph_inode_xattr, GFP_NOFS);
1225 	if (!xattr)
1226 		goto out;
1227 
1228 	prealloc_cf = ceph_alloc_cap_flush();
1229 	if (!prealloc_cf)
1230 		goto out;
1231 
1232 	spin_lock(&ci->i_ceph_lock);
1233 retry:
1234 	issued = __ceph_caps_issued(ci, NULL);
1235 	required_blob_size = __get_required_blob_size(ci, name_len, val_len);
1236 	if ((ci->i_xattrs.version == 0) || !(issued & CEPH_CAP_XATTR_EXCL) ||
1237 	    (required_blob_size > mdsc->mdsmap->m_max_xattr_size)) {
1238 		doutc(cl, "sync version: %llu size: %d max: %llu\n",
1239 		      ci->i_xattrs.version, required_blob_size,
1240 		      mdsc->mdsmap->m_max_xattr_size);
1241 		goto do_sync;
1242 	}
1243 
1244 	if (!lock_snap_rwsem && !ci->i_head_snapc) {
1245 		lock_snap_rwsem = true;
1246 		if (!down_read_trylock(&mdsc->snap_rwsem)) {
1247 			spin_unlock(&ci->i_ceph_lock);
1248 			down_read(&mdsc->snap_rwsem);
1249 			spin_lock(&ci->i_ceph_lock);
1250 			goto retry;
1251 		}
1252 	}
1253 
1254 	doutc(cl, "%p %llx.%llx name '%s' issued %s\n", inode,
1255 	      ceph_vinop(inode), name, ceph_cap_string(issued));
1256 	__build_xattrs(inode);
1257 
1258 	/*
1259 	 * __build_xattrs() may have released and reacquired i_ceph_lock,
1260 	 * during which handle_cap_grant() could have replaced i_xattrs.blob
1261 	 * with a newer MDS-provided blob and bumped i_xattrs.version. If that
1262 	 * caused __build_xattrs() to rebuild the rb-tree from the new blob,
1263 	 * count/names_size/vals_size may now be larger than when
1264 	 * required_blob_size was computed above. Recompute it here so the
1265 	 * prealloc_blob size check below reflects the current tree state.
1266 	 */
1267 	required_blob_size = __get_required_blob_size(ci, name_len, val_len);
1268 	if (required_blob_size > mdsc->mdsmap->m_max_xattr_size) {
1269 		doutc(cl, "sync (size too large): %d > %llu\n",
1270 		      required_blob_size, mdsc->mdsmap->m_max_xattr_size);
1271 		goto do_sync;
1272 	}
1273 
1274 	if (!ci->i_xattrs.prealloc_blob ||
1275 	    required_blob_size > ci->i_xattrs.prealloc_blob->alloc_len) {
1276 		struct ceph_buffer *blob;
1277 
1278 		spin_unlock(&ci->i_ceph_lock);
1279 		ceph_buffer_put(old_blob); /* Shouldn't be required */
1280 		doutc(cl, " pre-allocating new blob size=%d\n",
1281 		      required_blob_size);
1282 		blob = ceph_buffer_new(required_blob_size, GFP_NOFS);
1283 		if (!blob)
1284 			goto do_sync_unlocked;
1285 		spin_lock(&ci->i_ceph_lock);
1286 		/* prealloc_blob can't be released while holding i_ceph_lock */
1287 		if (ci->i_xattrs.prealloc_blob)
1288 			old_blob = ci->i_xattrs.prealloc_blob;
1289 		ci->i_xattrs.prealloc_blob = blob;
1290 		goto retry;
1291 	}
1292 
1293 	err = __set_xattr(ci, newname, name_len, newval, val_len,
1294 			  flags, value ? 1 : -1, &xattr);
1295 
1296 	if (!err) {
1297 		dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL,
1298 					       &prealloc_cf);
1299 		ci->i_xattrs.dirty = true;
1300 		inode_set_ctime_current(inode);
1301 	}
1302 
1303 	spin_unlock(&ci->i_ceph_lock);
1304 	ceph_buffer_put(old_blob);
1305 	if (lock_snap_rwsem)
1306 		up_read(&mdsc->snap_rwsem);
1307 	if (dirty)
1308 		__mark_inode_dirty(inode, dirty);
1309 	ceph_free_cap_flush(prealloc_cf);
1310 	return err;
1311 
1312 do_sync:
1313 	spin_unlock(&ci->i_ceph_lock);
1314 	ceph_buffer_put(old_blob);
1315 do_sync_unlocked:
1316 	if (lock_snap_rwsem)
1317 		up_read(&mdsc->snap_rwsem);
1318 
1319 	/* security module set xattr while filling trace */
1320 	if (current->journal_info) {
1321 		pr_warn_ratelimited_client(cl,
1322 				"sync %p %llx.%llx during filling trace\n",
1323 				inode, ceph_vinop(inode));
1324 		err = -EBUSY;
1325 	} else {
1326 		err = ceph_sync_setxattr(inode, name, value, size, flags);
1327 		if (err >= 0 && check_realm) {
1328 			/* check if snaprealm was created for quota inode */
1329 			spin_lock(&ci->i_ceph_lock);
1330 			if ((ci->i_max_files || ci->i_max_bytes) &&
1331 			    !(ci->i_snap_realm &&
1332 			      ci->i_snap_realm->ino == ci->i_vino.ino))
1333 				err = -EOPNOTSUPP;
1334 			spin_unlock(&ci->i_ceph_lock);
1335 		}
1336 	}
1337 out:
1338 	ceph_free_cap_flush(prealloc_cf);
1339 	kfree(newname);
1340 	kfree(newval);
1341 	kfree(xattr);
1342 	return err;
1343 }
1344 
ceph_get_xattr_handler(const struct xattr_handler * handler,struct dentry * dentry,struct inode * inode,const char * name,void * value,size_t size)1345 static int ceph_get_xattr_handler(const struct xattr_handler *handler,
1346 				  struct dentry *dentry, struct inode *inode,
1347 				  const char *name, void *value, size_t size)
1348 {
1349 	if (!ceph_is_valid_xattr(name))
1350 		return -EOPNOTSUPP;
1351 	return __ceph_getxattr(inode, name, value, size);
1352 }
1353 
ceph_set_xattr_handler(const struct xattr_handler * handler,struct mnt_idmap * idmap,struct dentry * unused,struct inode * inode,const char * name,const void * value,size_t size,int flags)1354 static int ceph_set_xattr_handler(const struct xattr_handler *handler,
1355 				  struct mnt_idmap *idmap,
1356 				  struct dentry *unused, struct inode *inode,
1357 				  const char *name, const void *value,
1358 				  size_t size, int flags)
1359 {
1360 	if (!ceph_is_valid_xattr(name))
1361 		return -EOPNOTSUPP;
1362 	return __ceph_setxattr(inode, name, value, size, flags);
1363 }
1364 
1365 static const struct xattr_handler ceph_other_xattr_handler = {
1366 	.prefix = "",  /* match any name => handlers called with full name */
1367 	.get = ceph_get_xattr_handler,
1368 	.set = ceph_set_xattr_handler,
1369 };
1370 
1371 #ifdef CONFIG_SECURITY
ceph_security_xattr_wanted(struct inode * in)1372 bool ceph_security_xattr_wanted(struct inode *in)
1373 {
1374 	return in->i_security != NULL;
1375 }
1376 
ceph_security_xattr_deadlock(struct inode * in)1377 bool ceph_security_xattr_deadlock(struct inode *in)
1378 {
1379 	struct ceph_inode_info *ci;
1380 	bool ret;
1381 	if (!in->i_security)
1382 		return false;
1383 	ci = ceph_inode(in);
1384 	spin_lock(&ci->i_ceph_lock);
1385 	ret = !(ci->i_ceph_flags & CEPH_I_SEC_INITED) &&
1386 	      !(ci->i_xattrs.version > 0 &&
1387 		__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0));
1388 	spin_unlock(&ci->i_ceph_lock);
1389 	return ret;
1390 }
1391 
1392 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
ceph_security_init_secctx(struct dentry * dentry,umode_t mode,struct ceph_acl_sec_ctx * as_ctx)1393 int ceph_security_init_secctx(struct dentry *dentry, umode_t mode,
1394 			   struct ceph_acl_sec_ctx *as_ctx)
1395 {
1396 	struct ceph_pagelist *pagelist = as_ctx->pagelist;
1397 	const char *name;
1398 	size_t name_len;
1399 	int err;
1400 
1401 	err = security_dentry_init_security(dentry, mode, &dentry->d_name,
1402 					    &name, &as_ctx->lsmctx);
1403 	if (err < 0) {
1404 		WARN_ON_ONCE(err != -EOPNOTSUPP);
1405 		err = 0; /* do nothing */
1406 		goto out;
1407 	}
1408 
1409 	err = -ENOMEM;
1410 	if (!pagelist) {
1411 		pagelist = ceph_pagelist_alloc(GFP_KERNEL);
1412 		if (!pagelist)
1413 			goto out;
1414 		err = ceph_pagelist_reserve(pagelist, PAGE_SIZE);
1415 		if (err)
1416 			goto out;
1417 		ceph_pagelist_encode_32(pagelist, 1);
1418 	}
1419 
1420 	/*
1421 	 * FIXME: Make security_dentry_init_security() generic. Currently
1422 	 * It only supports single security module and only selinux has
1423 	 * dentry_init_security hook.
1424 	 */
1425 	name_len = strlen(name);
1426 	err = ceph_pagelist_reserve(pagelist,
1427 				    4 * 2 + name_len + as_ctx->lsmctx.len);
1428 	if (err)
1429 		goto out;
1430 
1431 	if (as_ctx->pagelist) {
1432 		/* update count of KV pairs */
1433 		BUG_ON(pagelist->length <= sizeof(__le32));
1434 		if (list_is_singular(&pagelist->head)) {
1435 			le32_add_cpu((__le32*)pagelist->mapped_tail, 1);
1436 		} else {
1437 			struct page *page = list_first_entry(&pagelist->head,
1438 							     struct page, lru);
1439 			void *addr = kmap_atomic(page);
1440 			le32_add_cpu((__le32*)addr, 1);
1441 			kunmap_atomic(addr);
1442 		}
1443 	} else {
1444 		as_ctx->pagelist = pagelist;
1445 	}
1446 
1447 	ceph_pagelist_encode_32(pagelist, name_len);
1448 	ceph_pagelist_append(pagelist, name, name_len);
1449 
1450 	ceph_pagelist_encode_32(pagelist, as_ctx->lsmctx.len);
1451 	ceph_pagelist_append(pagelist, as_ctx->lsmctx.context,
1452 			     as_ctx->lsmctx.len);
1453 
1454 	err = 0;
1455 out:
1456 	if (pagelist && !as_ctx->pagelist)
1457 		ceph_pagelist_release(pagelist);
1458 	return err;
1459 }
1460 #endif /* CONFIG_CEPH_FS_SECURITY_LABEL */
1461 #endif /* CONFIG_SECURITY */
1462 
ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx * as_ctx)1463 void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx)
1464 {
1465 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1466 	posix_acl_release(as_ctx->acl);
1467 	posix_acl_release(as_ctx->default_acl);
1468 #endif
1469 #ifdef CONFIG_CEPH_FS_SECURITY_LABEL
1470 	security_release_secctx(&as_ctx->lsmctx);
1471 #endif
1472 #ifdef CONFIG_FS_ENCRYPTION
1473 	kfree(as_ctx->fscrypt_auth);
1474 #endif
1475 	if (as_ctx->pagelist)
1476 		ceph_pagelist_release(as_ctx->pagelist);
1477 }
1478 
1479 /*
1480  * List of handlers for synthetic system.* attributes. Other
1481  * attributes are handled directly.
1482  */
1483 const struct xattr_handler * const ceph_xattr_handlers[] = {
1484 	&ceph_other_xattr_handler,
1485 	NULL,
1486 };
1487