1 #include <linux/fs.h>
2 #include <linux/nfs.h>
3 #include <linux/nfs3.h>
4 #include <linux/nfs_fs.h>
5 #include <linux/posix_acl_xattr.h>
6 #include <linux/nfsacl.h>
7
8 #include "internal.h"
9
10 #define NFSDBG_FACILITY NFSDBG_PROC
11
nfs3_listxattr(struct dentry * dentry,char * buffer,size_t size)12 ssize_t nfs3_listxattr(struct dentry *dentry, char *buffer, size_t size)
13 {
14 struct inode *inode = dentry->d_inode;
15 struct posix_acl *acl;
16 int pos=0, len=0;
17
18 # define output(s) do { \
19 if (pos + sizeof(s) <= size) { \
20 memcpy(buffer + pos, s, sizeof(s)); \
21 pos += sizeof(s); \
22 } \
23 len += sizeof(s); \
24 } while(0)
25
26 acl = nfs3_proc_getacl(inode, ACL_TYPE_ACCESS);
27 if (IS_ERR(acl))
28 return PTR_ERR(acl);
29 if (acl) {
30 output("system.posix_acl_access");
31 posix_acl_release(acl);
32 }
33
34 if (S_ISDIR(inode->i_mode)) {
35 acl = nfs3_proc_getacl(inode, ACL_TYPE_DEFAULT);
36 if (IS_ERR(acl))
37 return PTR_ERR(acl);
38 if (acl) {
39 output("system.posix_acl_default");
40 posix_acl_release(acl);
41 }
42 }
43
44 # undef output
45
46 if (!buffer || len <= size)
47 return len;
48 return -ERANGE;
49 }
50
nfs3_getxattr(struct dentry * dentry,const char * name,void * buffer,size_t size)51 ssize_t nfs3_getxattr(struct dentry *dentry, const char *name,
52 void *buffer, size_t size)
53 {
54 struct inode *inode = dentry->d_inode;
55 struct posix_acl *acl;
56 int type, error = 0;
57
58 if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0)
59 type = ACL_TYPE_ACCESS;
60 else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0)
61 type = ACL_TYPE_DEFAULT;
62 else
63 return -EOPNOTSUPP;
64
65 acl = nfs3_proc_getacl(inode, type);
66 if (IS_ERR(acl))
67 return PTR_ERR(acl);
68 else if (acl) {
69 if (type == ACL_TYPE_ACCESS && acl->a_count == 0)
70 error = -ENODATA;
71 else
72 error = posix_acl_to_xattr(acl, buffer, size);
73 posix_acl_release(acl);
74 } else
75 error = -ENODATA;
76
77 return error;
78 }
79
nfs3_setxattr(struct dentry * dentry,const char * name,const void * value,size_t size,int flags)80 int nfs3_setxattr(struct dentry *dentry, const char *name,
81 const void *value, size_t size, int flags)
82 {
83 struct inode *inode = dentry->d_inode;
84 struct posix_acl *acl;
85 int type, error;
86
87 if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0)
88 type = ACL_TYPE_ACCESS;
89 else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0)
90 type = ACL_TYPE_DEFAULT;
91 else
92 return -EOPNOTSUPP;
93
94 acl = posix_acl_from_xattr(value, size);
95 if (IS_ERR(acl))
96 return PTR_ERR(acl);
97 error = nfs3_proc_setacl(inode, type, acl);
98 posix_acl_release(acl);
99
100 return error;
101 }
102
nfs3_removexattr(struct dentry * dentry,const char * name)103 int nfs3_removexattr(struct dentry *dentry, const char *name)
104 {
105 struct inode *inode = dentry->d_inode;
106 int type;
107
108 if (strcmp(name, POSIX_ACL_XATTR_ACCESS) == 0)
109 type = ACL_TYPE_ACCESS;
110 else if (strcmp(name, POSIX_ACL_XATTR_DEFAULT) == 0)
111 type = ACL_TYPE_DEFAULT;
112 else
113 return -EOPNOTSUPP;
114
115 return nfs3_proc_setacl(inode, type, NULL);
116 }
117
__nfs3_forget_cached_acls(struct nfs_inode * nfsi)118 static void __nfs3_forget_cached_acls(struct nfs_inode *nfsi)
119 {
120 if (!IS_ERR(nfsi->acl_access)) {
121 posix_acl_release(nfsi->acl_access);
122 nfsi->acl_access = ERR_PTR(-EAGAIN);
123 }
124 if (!IS_ERR(nfsi->acl_default)) {
125 posix_acl_release(nfsi->acl_default);
126 nfsi->acl_default = ERR_PTR(-EAGAIN);
127 }
128 }
129
nfs3_forget_cached_acls(struct inode * inode)130 void nfs3_forget_cached_acls(struct inode *inode)
131 {
132 dprintk("NFS: nfs3_forget_cached_acls(%s/%ld)\n", inode->i_sb->s_id,
133 inode->i_ino);
134 spin_lock(&inode->i_lock);
135 __nfs3_forget_cached_acls(NFS_I(inode));
136 spin_unlock(&inode->i_lock);
137 }
138
nfs3_get_cached_acl(struct inode * inode,int type)139 static struct posix_acl *nfs3_get_cached_acl(struct inode *inode, int type)
140 {
141 struct nfs_inode *nfsi = NFS_I(inode);
142 struct posix_acl *acl = ERR_PTR(-EINVAL);
143
144 spin_lock(&inode->i_lock);
145 switch(type) {
146 case ACL_TYPE_ACCESS:
147 acl = nfsi->acl_access;
148 break;
149
150 case ACL_TYPE_DEFAULT:
151 acl = nfsi->acl_default;
152 break;
153
154 default:
155 goto out;
156 }
157 if (IS_ERR(acl))
158 acl = ERR_PTR(-EAGAIN);
159 else
160 acl = posix_acl_dup(acl);
161 out:
162 spin_unlock(&inode->i_lock);
163 dprintk("NFS: nfs3_get_cached_acl(%s/%ld, %d) = %p\n", inode->i_sb->s_id,
164 inode->i_ino, type, acl);
165 return acl;
166 }
167
nfs3_cache_acls(struct inode * inode,struct posix_acl * acl,struct posix_acl * dfacl)168 static void nfs3_cache_acls(struct inode *inode, struct posix_acl *acl,
169 struct posix_acl *dfacl)
170 {
171 struct nfs_inode *nfsi = NFS_I(inode);
172
173 dprintk("nfs3_cache_acls(%s/%ld, %p, %p)\n", inode->i_sb->s_id,
174 inode->i_ino, acl, dfacl);
175 spin_lock(&inode->i_lock);
176 __nfs3_forget_cached_acls(NFS_I(inode));
177 if (!IS_ERR(acl))
178 nfsi->acl_access = posix_acl_dup(acl);
179 if (!IS_ERR(dfacl))
180 nfsi->acl_default = posix_acl_dup(dfacl);
181 spin_unlock(&inode->i_lock);
182 }
183
nfs3_proc_getacl(struct inode * inode,int type)184 struct posix_acl *nfs3_proc_getacl(struct inode *inode, int type)
185 {
186 struct nfs_server *server = NFS_SERVER(inode);
187 struct nfs_fattr fattr;
188 struct page *pages[NFSACL_MAXPAGES] = { };
189 struct nfs3_getaclargs args = {
190 .fh = NFS_FH(inode),
191 /* The xdr layer may allocate pages here. */
192 .pages = pages,
193 };
194 struct nfs3_getaclres res = {
195 .fattr = &fattr,
196 };
197 struct rpc_message msg = {
198 .rpc_argp = &args,
199 .rpc_resp = &res,
200 };
201 struct posix_acl *acl;
202 int status, count;
203
204 if (!nfs_server_capable(inode, NFS_CAP_ACLS))
205 return ERR_PTR(-EOPNOTSUPP);
206
207 status = nfs_revalidate_inode(server, inode);
208 if (status < 0)
209 return ERR_PTR(status);
210 if (NFS_I(inode)->cache_validity & NFS_INO_INVALID_ACL)
211 nfs_zap_acl_cache(inode);
212 acl = nfs3_get_cached_acl(inode, type);
213 if (acl != ERR_PTR(-EAGAIN))
214 return acl;
215 acl = NULL;
216
217 /*
218 * Only get the access acl when explicitly requested: We don't
219 * need it for access decisions, and only some applications use
220 * it. Applications which request the access acl first are not
221 * penalized from this optimization.
222 */
223 if (type == ACL_TYPE_ACCESS)
224 args.mask |= NFS_ACLCNT|NFS_ACL;
225 if (S_ISDIR(inode->i_mode))
226 args.mask |= NFS_DFACLCNT|NFS_DFACL;
227 if (args.mask == 0)
228 return NULL;
229
230 dprintk("NFS call getacl\n");
231 msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL];
232 nfs_fattr_init(&fattr);
233 status = rpc_call_sync(server->client_acl, &msg, 0);
234 dprintk("NFS reply getacl: %d\n", status);
235
236 /* pages may have been allocated at the xdr layer. */
237 for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++)
238 __free_page(args.pages[count]);
239
240 switch (status) {
241 case 0:
242 status = nfs_refresh_inode(inode, &fattr);
243 break;
244 case -EPFNOSUPPORT:
245 case -EPROTONOSUPPORT:
246 dprintk("NFS_V3_ACL extension not supported; disabling\n");
247 server->caps &= ~NFS_CAP_ACLS;
248 case -ENOTSUPP:
249 status = -EOPNOTSUPP;
250 default:
251 goto getout;
252 }
253 if ((args.mask & res.mask) != args.mask) {
254 status = -EIO;
255 goto getout;
256 }
257
258 if (res.acl_access != NULL) {
259 if (posix_acl_equiv_mode(res.acl_access, NULL) == 0) {
260 posix_acl_release(res.acl_access);
261 res.acl_access = NULL;
262 }
263 }
264 nfs3_cache_acls(inode,
265 (res.mask & NFS_ACL) ? res.acl_access : ERR_PTR(-EINVAL),
266 (res.mask & NFS_DFACL) ? res.acl_default : ERR_PTR(-EINVAL));
267
268 switch(type) {
269 case ACL_TYPE_ACCESS:
270 acl = res.acl_access;
271 res.acl_access = NULL;
272 break;
273
274 case ACL_TYPE_DEFAULT:
275 acl = res.acl_default;
276 res.acl_default = NULL;
277 }
278
279 getout:
280 posix_acl_release(res.acl_access);
281 posix_acl_release(res.acl_default);
282
283 if (status != 0) {
284 posix_acl_release(acl);
285 acl = ERR_PTR(status);
286 }
287 return acl;
288 }
289
nfs3_proc_setacls(struct inode * inode,struct posix_acl * acl,struct posix_acl * dfacl)290 static int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl,
291 struct posix_acl *dfacl)
292 {
293 struct nfs_server *server = NFS_SERVER(inode);
294 struct nfs_fattr fattr;
295 struct page *pages[NFSACL_MAXPAGES];
296 struct nfs3_setaclargs args = {
297 .inode = inode,
298 .mask = NFS_ACL,
299 .acl_access = acl,
300 .pages = pages,
301 };
302 struct rpc_message msg = {
303 .rpc_argp = &args,
304 .rpc_resp = &fattr,
305 };
306 int status;
307
308 status = -EOPNOTSUPP;
309 if (!nfs_server_capable(inode, NFS_CAP_ACLS))
310 goto out;
311
312 /* We are doing this here, because XDR marshalling can only
313 return -ENOMEM. */
314 status = -ENOSPC;
315 if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES)
316 goto out;
317 if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES)
318 goto out;
319 if (S_ISDIR(inode->i_mode)) {
320 args.mask |= NFS_DFACL;
321 args.acl_default = dfacl;
322 args.len = nfsacl_size(acl, dfacl);
323 } else
324 args.len = nfsacl_size(acl, NULL);
325
326 if (args.len > NFS_ACL_INLINE_BUFSIZE) {
327 unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT);
328
329 status = -ENOMEM;
330 do {
331 args.pages[args.npages] = alloc_page(GFP_KERNEL);
332 if (args.pages[args.npages] == NULL)
333 goto out_freepages;
334 args.npages++;
335 } while (args.npages < npages);
336 }
337
338 dprintk("NFS call setacl\n");
339 msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL];
340 nfs_fattr_init(&fattr);
341 status = rpc_call_sync(server->client_acl, &msg, 0);
342 nfs_access_zap_cache(inode);
343 nfs_zap_acl_cache(inode);
344 dprintk("NFS reply setacl: %d\n", status);
345
346 switch (status) {
347 case 0:
348 status = nfs_refresh_inode(inode, &fattr);
349 nfs3_cache_acls(inode, acl, dfacl);
350 break;
351 case -EPFNOSUPPORT:
352 case -EPROTONOSUPPORT:
353 dprintk("NFS_V3_ACL SETACL RPC not supported"
354 "(will not retry)\n");
355 server->caps &= ~NFS_CAP_ACLS;
356 case -ENOTSUPP:
357 status = -EOPNOTSUPP;
358 }
359 out_freepages:
360 while (args.npages != 0) {
361 args.npages--;
362 __free_page(args.pages[args.npages]);
363 }
364 out:
365 return status;
366 }
367
nfs3_proc_setacl(struct inode * inode,int type,struct posix_acl * acl)368 int nfs3_proc_setacl(struct inode *inode, int type, struct posix_acl *acl)
369 {
370 struct posix_acl *alloc = NULL, *dfacl = NULL;
371 int status;
372
373 if (S_ISDIR(inode->i_mode)) {
374 switch(type) {
375 case ACL_TYPE_ACCESS:
376 alloc = dfacl = nfs3_proc_getacl(inode,
377 ACL_TYPE_DEFAULT);
378 if (IS_ERR(alloc))
379 goto fail;
380 break;
381
382 case ACL_TYPE_DEFAULT:
383 dfacl = acl;
384 alloc = acl = nfs3_proc_getacl(inode,
385 ACL_TYPE_ACCESS);
386 if (IS_ERR(alloc))
387 goto fail;
388 break;
389
390 default:
391 return -EINVAL;
392 }
393 } else if (type != ACL_TYPE_ACCESS)
394 return -EINVAL;
395
396 if (acl == NULL) {
397 alloc = acl = posix_acl_from_mode(inode->i_mode, GFP_KERNEL);
398 if (IS_ERR(alloc))
399 goto fail;
400 }
401 status = nfs3_proc_setacls(inode, acl, dfacl);
402 posix_acl_release(alloc);
403 return status;
404
405 fail:
406 return PTR_ERR(alloc);
407 }
408
nfs3_proc_set_default_acl(struct inode * dir,struct inode * inode,mode_t mode)409 int nfs3_proc_set_default_acl(struct inode *dir, struct inode *inode,
410 mode_t mode)
411 {
412 struct posix_acl *dfacl, *acl;
413 int error = 0;
414
415 dfacl = nfs3_proc_getacl(dir, ACL_TYPE_DEFAULT);
416 if (IS_ERR(dfacl)) {
417 error = PTR_ERR(dfacl);
418 return (error == -EOPNOTSUPP) ? 0 : error;
419 }
420 if (!dfacl)
421 return 0;
422 acl = posix_acl_clone(dfacl, GFP_KERNEL);
423 error = -ENOMEM;
424 if (!acl)
425 goto out_release_dfacl;
426 error = posix_acl_create_masq(acl, &mode);
427 if (error < 0)
428 goto out_release_acl;
429 error = nfs3_proc_setacls(inode, acl, S_ISDIR(inode->i_mode) ?
430 dfacl : NULL);
431 out_release_acl:
432 posix_acl_release(acl);
433 out_release_dfacl:
434 posix_acl_release(dfacl);
435 return error;
436 }
437