[linux-2.6-block.git] / fs / hfsplus / posix_acl.c

/*
 * linux/fs/hfsplus/posix_acl.c
 *
 * Vyacheslav Dubeyko <slava@dubeyko.com>
 *
 * Handler for Posix Access Control Lists (ACLs) support.
 */

#include "hfsplus_fs.h"
#include "xattr.h"
#include "acl.h"

struct posix_acl *hfsplus_get_posix_acl(struct inode *inode, int type)
{
	struct posix_acl *acl;
	char *xattr_name;
	char *value = NULL;
	ssize_t size;

	acl = get_cached_acl(inode, type);
	if (acl != ACL_NOT_CACHED)
		return acl;

	switch (type) {
	case ACL_TYPE_ACCESS:
		xattr_name = POSIX_ACL_XATTR_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		xattr_name = POSIX_ACL_XATTR_DEFAULT;
		break;
	default:
		return ERR_PTR(-EINVAL);
	}

	size = __hfsplus_getxattr(inode, xattr_name, NULL, 0);

	if (size > 0) {
		value = (char *)hfsplus_alloc_attr_entry();
		if (unlikely(!value))
			return ERR_PTR(-ENOMEM);
		size = __hfsplus_getxattr(inode, xattr_name, value, size);
	}

	if (size > 0)
		acl = posix_acl_from_xattr(&init_user_ns, value, size);
	else if (size == -ENODATA)
		acl = NULL;
	else
		acl = ERR_PTR(size);

	hfsplus_destroy_attr_entry((hfsplus_attr_entry *)value);

	if (!IS_ERR(acl))
		set_cached_acl(inode, type, acl);

	return acl;
}

static int hfsplus_set_posix_acl(struct inode *inode,
					int type,
					struct posix_acl *acl)
{
	int err;
	char *xattr_name;
	size_t size = 0;
	char *value = NULL;

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	switch (type) {
	case ACL_TYPE_ACCESS:
		xattr_name = POSIX_ACL_XATTR_ACCESS;
		if (acl) {
			err = posix_acl_equiv_mode(acl, &inode->i_mode);
			if (err < 0)
				return err;
		}
		err = 0;
		break;

	case ACL_TYPE_DEFAULT:
		xattr_name = POSIX_ACL_XATTR_DEFAULT;
		if (!S_ISDIR(inode->i_mode))
			return acl ? -EACCES : 0;
		break;

	default:
		return -EINVAL;
	}

	if (acl) {
		size = posix_acl_xattr_size(acl->a_count);
		if (unlikely(size > HFSPLUS_MAX_INLINE_DATA_SIZE))
			return -ENOMEM;
		value = (char *)hfsplus_alloc_attr_entry();
		if (unlikely(!value))
			return -ENOMEM;
		err = posix_acl_to_xattr(&init_user_ns, acl, value, size);
		if (unlikely(err < 0))
			goto end_set_acl;
	}

	err = __hfsplus_setxattr(inode, xattr_name, value, size, 0);

end_set_acl:
	hfsplus_destroy_attr_entry((hfsplus_attr_entry *)value);

	if (!err)
		set_cached_acl(inode, type, acl);

	return err;
}

int hfsplus_init_posix_acl(struct inode *inode, struct inode *dir)
{
	int err = 0;
	struct posix_acl *acl = NULL;

	hfs_dbg(ACL_MOD,
		"[%s]: ino %lu, dir->ino %lu\n",
		__func__, inode->i_ino, dir->i_ino);

	if (S_ISLNK(inode->i_mode))
		return 0;

	acl = hfsplus_get_posix_acl(dir, ACL_TYPE_DEFAULT);
	if (IS_ERR(acl))
		return PTR_ERR(acl);

	if (acl) {
		if (S_ISDIR(inode->i_mode)) {
			err = hfsplus_set_posix_acl(inode,
							ACL_TYPE_DEFAULT,
							acl);
			if (unlikely(err))
				goto init_acl_cleanup;
		}

		err = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
		if (unlikely(err < 0))
			return err;

		if (err > 0)
			err = hfsplus_set_posix_acl(inode,
							ACL_TYPE_ACCESS,
							acl);
	} else
		inode->i_mode &= ~current_umask();

init_acl_cleanup:
	posix_acl_release(acl);
	return err;
}

int hfsplus_posix_acl_chmod(struct inode *inode)
{
	int err;
	struct posix_acl *acl;

	hfs_dbg(ACL_MOD, "[%s]: ino %lu\n", __func__, inode->i_ino);

	if (S_ISLNK(inode->i_mode))
		return -EOPNOTSUPP;

	acl = hfsplus_get_posix_acl(inode, ACL_TYPE_ACCESS);
	if (IS_ERR(acl) || !acl)
		return PTR_ERR(acl);

	err = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
	if (unlikely(err))
		return err;

	err = hfsplus_set_posix_acl(inode, ACL_TYPE_ACCESS, acl);
	posix_acl_release(acl);
	return err;
}

static int hfsplus_xattr_get_posix_acl(struct dentry *dentry,
					const char *name,
					void *buffer,
					size_t size,
					int type)
{
	int err = 0;
	struct posix_acl *acl;

	hfs_dbg(ACL_MOD,
		"[%s]: ino %lu, buffer %p, size %zu, type %#x\n",
		__func__, dentry->d_inode->i_ino, buffer, size, type);

	if (strcmp(name, "") != 0)
		return -EINVAL;

	acl = hfsplus_get_posix_acl(dentry->d_inode, type);
	if (IS_ERR(acl))
		return PTR_ERR(acl);
	if (acl == NULL)
		return -ENODATA;

	err = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
	posix_acl_release(acl);

	return err;
}

static int hfsplus_xattr_set_posix_acl(struct dentry *dentry,
					const char *name,
					const void *value,
					size_t size,
					int flags,
					int type)
{
	int err = 0;
	struct inode *inode = dentry->d_inode;
	struct posix_acl *acl = NULL;

	hfs_dbg(ACL_MOD,
		"[%s]: ino %lu, value %p, size %zu, flags %#x, type %#x\n",
		__func__, inode->i_ino, value, size, flags, type);

	if (strcmp(name, "") != 0)
		return -EINVAL;

	if (!inode_owner_or_capable(inode))
		return -EPERM;

	if (value) {
		acl = posix_acl_from_xattr(&init_user_ns, value, size);
		if (IS_ERR(acl))
			return PTR_ERR(acl);
		else if (acl) {
			err = posix_acl_valid(acl);
			if (err)
				goto end_xattr_set_acl;
		}
	}

	err = hfsplus_set_posix_acl(inode, type, acl);

end_xattr_set_acl:
	posix_acl_release(acl);
	return err;
}

static size_t hfsplus_xattr_list_posix_acl(struct dentry *dentry,
						char *list,
						size_t list_size,
						const char *name,
						size_t name_len,
						int type)
{
	/*
	 * This method is not used.
	 * It is used hfsplus_listxattr() instead of generic_listxattr().
	 */
	return -EOPNOTSUPP;
}

const struct xattr_handler hfsplus_xattr_acl_access_handler = {
	.prefix	= POSIX_ACL_XATTR_ACCESS,
	.flags	= ACL_TYPE_ACCESS,
	.list	= hfsplus_xattr_list_posix_acl,
	.get	= hfsplus_xattr_get_posix_acl,
	.set	= hfsplus_xattr_set_posix_acl,
};

const struct xattr_handler hfsplus_xattr_acl_default_handler = {
	.prefix	= POSIX_ACL_XATTR_DEFAULT,
	.flags	= ACL_TYPE_DEFAULT,
	.list	= hfsplus_xattr_list_posix_acl,
	.get	= hfsplus_xattr_get_posix_acl,
	.set	= hfsplus_xattr_set_posix_acl,
};
Commit	Line	Data
eef80d4a VD	1	/*
	2	* linux/fs/hfsplus/posix_acl.c
	3	*
	4	* Vyacheslav Dubeyko <slava@dubeyko.com>
	5	*
	6	* Handler for Posix Access Control Lists (ACLs) support.
	7	*/
	8
	9	#include "hfsplus_fs.h"
	10	#include "xattr.h"
	11	#include "acl.h"
	12
	13	struct posix_acl hfsplus_get_posix_acl(struct inode inode, int type)
	14	{
	15	struct posix_acl *acl;
	16	char *xattr_name;
	17	char *value = NULL;
	18	ssize_t size;
	19
	20	acl = get_cached_acl(inode, type);
	21	if (acl != ACL_NOT_CACHED)
	22	return acl;
	23
	24	switch (type) {
	25	case ACL_TYPE_ACCESS:
	26	xattr_name = POSIX_ACL_XATTR_ACCESS;
	27	break;
	28	case ACL_TYPE_DEFAULT:
	29	xattr_name = POSIX_ACL_XATTR_DEFAULT;
	30	break;
	31	default:
	32	return ERR_PTR(-EINVAL);
	33	}
	34
	35	size = __hfsplus_getxattr(inode, xattr_name, NULL, 0);
	36
	37	if (size > 0) {
	38	value = (char *)hfsplus_alloc_attr_entry();
	39	if (unlikely(!value))
	40	return ERR_PTR(-ENOMEM);
	41	size = __hfsplus_getxattr(inode, xattr_name, value, size);
	42	}
	43
	44	if (size > 0)
	45	acl = posix_acl_from_xattr(&init_user_ns, value, size);
	46	else if (size == -ENODATA)
	47	acl = NULL;
	48	else
	49	acl = ERR_PTR(size);
	50
	51	hfsplus_destroy_attr_entry((hfsplus_attr_entry *)value);
	52
	53	if (!IS_ERR(acl))
	54	set_cached_acl(inode, type, acl);
	55
	56	return acl;
	57	}
	58
	59	static int hfsplus_set_posix_acl(struct inode *inode,
	60	int type,
	61	struct posix_acl *acl)
	62	{
	63	int err;
	64	char *xattr_name;
65	size_t size = 0;
66	char *value = NULL;
67
68	if (S_ISLNK(inode->i_mode))
69	return -EOPNOTSUPP;
70
71	switch (type) {
72	case ACL_TYPE_ACCESS:
73	xattr_name = POSIX_ACL_XATTR_ACCESS;
74	if (acl) {
75	err = posix_acl_equiv_mode(acl, &inode->i_mode);
76	if (err < 0)
77	return err;
78	}
79	err = 0;
80	break;
81
82	case ACL_TYPE_DEFAULT:
83	xattr_name = POSIX_ACL_XATTR_DEFAULT;
84	if (!S_ISDIR(inode->i_mode))
85	return acl ? -EACCES : 0;
86	break;
87
88	default:
89	return -EINVAL;
90	}
91
92	if (acl) {
93	size = posix_acl_xattr_size(acl->a_count);
94	if (unlikely(size > HFSPLUS_MAX_INLINE_DATA_SIZE))
95	return -ENOMEM;
96	value = (char *)hfsplus_alloc_attr_entry();
97	if (unlikely(!value))
98	return -ENOMEM;
99	err = posix_acl_to_xattr(&init_user_ns, acl, value, size);
100	if (unlikely(err < 0))
101	goto end_set_acl;
102	}
103
104	err = __hfsplus_setxattr(inode, xattr_name, value, size, 0);
105
106	end_set_acl:
107	hfsplus_destroy_attr_entry((hfsplus_attr_entry *)value);
108
109	if (!err)
110	set_cached_acl(inode, type, acl);
111
112	return err;
113	}
114
115	int hfsplus_init_posix_acl(struct inode inode, struct inode dir)
116	{
117	int err = 0;
118	struct posix_acl *acl = NULL;
119
120	hfs_dbg(ACL_MOD,
121	"[%s]: ino %lu, dir->ino %lu\n",
122	__func__, inode->i_ino, dir->i_ino);
123
124	if (S_ISLNK(inode->i_mode))
125	return 0;
126
127	acl = hfsplus_get_posix_acl(dir, ACL_TYPE_DEFAULT);
128	if (IS_ERR(acl))
129	return PTR_ERR(acl);
130
131	if (acl) {
132	if (S_ISDIR(inode->i_mode)) {
133	err = hfsplus_set_posix_acl(inode,
134	ACL_TYPE_DEFAULT,
135	acl);
136	if (unlikely(err))
137	goto init_acl_cleanup;
138	}
139
140	err = posix_acl_create(&acl, GFP_NOFS, &inode->i_mode);
141	if (unlikely(err < 0))
142	return err;
143
144	if (err > 0)
145	err = hfsplus_set_posix_acl(inode,
146	ACL_TYPE_ACCESS,
147	acl);
148	} else
149	inode->i_mode &= ~current_umask();
150
151	init_acl_cleanup:
152	posix_acl_release(acl);
153	return err;
154	}
155
156	int hfsplus_posix_acl_chmod(struct inode *inode)
157	{
158	int err;
159	struct posix_acl *acl;
160
161	hfs_dbg(ACL_MOD, "[%s]: ino %lu\n", __func__, inode->i_ino);
162
163	if (S_ISLNK(inode->i_mode))
164	return -EOPNOTSUPP;
165
166	acl = hfsplus_get_posix_acl(inode, ACL_TYPE_ACCESS);
167	if (IS_ERR(acl) \|\| !acl)
168	return PTR_ERR(acl);
169
170	err = posix_acl_chmod(&acl, GFP_KERNEL, inode->i_mode);
171	if (unlikely(err))
172	return err;
173
174	err = hfsplus_set_posix_acl(inode, ACL_TYPE_ACCESS, acl);
175	posix_acl_release(acl);
176	return err;
177	}
178
179	static int hfsplus_xattr_get_posix_acl(struct dentry *dentry,
180	const char *name,
181	void *buffer,
182	size_t size,
183	int type)
184	{
185	int err = 0;
186	struct posix_acl *acl;
187
188	hfs_dbg(ACL_MOD,
189	"[%s]: ino %lu, buffer %p, size %zu, type %#x\n",
190	__func__, dentry->d_inode->i_ino, buffer, size, type);
191
192	if (strcmp(name, "") != 0)
193	return -EINVAL;
194
195	acl = hfsplus_get_posix_acl(dentry->d_inode, type);
196	if (IS_ERR(acl))
197	return PTR_ERR(acl);
198	if (acl == NULL)
199	return -ENODATA;
200
201	err = posix_acl_to_xattr(&init_user_ns, acl, buffer, size);
202	posix_acl_release(acl);
203
204	return err;
205	}
206
207	static int hfsplus_xattr_set_posix_acl(struct dentry *dentry,
208	const char *name,
209	const void *value,
210	size_t size,
211	int flags,
212	int type)
213	{
214	int err = 0;
215	struct inode *inode = dentry->d_inode;
216	struct posix_acl *acl = NULL;
217
218	hfs_dbg(ACL_MOD,
219	"[%s]: ino %lu, value %p, size %zu, flags %#x, type %#x\n",
220	__func__, inode->i_ino, value, size, flags, type);
221
222	if (strcmp(name, "") != 0)
223	return -EINVAL;
224
225	if (!inode_owner_or_capable(inode))
226	return -EPERM;
227
228	if (value) {
229	acl = posix_acl_from_xattr(&init_user_ns, value, size);
230	if (IS_ERR(acl))
231	return PTR_ERR(acl);
232	else if (acl) {
233	err = posix_acl_valid(acl);
234	if (err)
235	goto end_xattr_set_acl;
236	}
237	}
238
239	err = hfsplus_set_posix_acl(inode, type, acl);
240
241	end_xattr_set_acl:
242	posix_acl_release(acl);
243	return err;
244	}
245
246	static size_t hfsplus_xattr_list_posix_acl(struct dentry *dentry,
247	char *list,
248	size_t list_size,
249	const char *name,
250	size_t name_len,
251	int type)
252	{
253	/*
254	* This method is not used.
255	* It is used hfsplus_listxattr() instead of generic_listxattr().
256	*/
257	return -EOPNOTSUPP;
258	}
259
260	const struct xattr_handler hfsplus_xattr_acl_access_handler = {
261	.prefix = POSIX_ACL_XATTR_ACCESS,
262	.flags = ACL_TYPE_ACCESS,
263	.list = hfsplus_xattr_list_posix_acl,
264	.get = hfsplus_xattr_get_posix_acl,
265	.set = hfsplus_xattr_set_posix_acl,
266	};
267
268	const struct xattr_handler hfsplus_xattr_acl_default_handler = {
269	.prefix = POSIX_ACL_XATTR_DEFAULT,
270	.flags = ACL_TYPE_DEFAULT,
271	.list = hfsplus_xattr_list_posix_acl,
272	.get = hfsplus_xattr_get_posix_acl,
273	.set = hfsplus_xattr_set_posix_acl,
274	};