aboutsummaryrefslogtreecommitdiff
path: root/fs/orangefs/acl.c
blob: 605e5a3506ec25b0898292eb1098e77b7f82b3d5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
// SPDX-License-Identifier: GPL-2.0
/*
 * (C) 2001 Clemson University and The University of Chicago
 *
 * See COPYING in top-level directory.
 */

#include "protocol.h"
#include "orangefs-kernel.h"
#include "orangefs-bufmap.h"
#include <linux/posix_acl_xattr.h>

struct posix_acl *orangefs_get_acl(struct inode *inode, int type, bool rcu)
{
	struct posix_acl *acl;
	int ret;
	char *key = NULL, *value = NULL;

	if (rcu)
		return ERR_PTR(-ECHILD);

	switch (type) {
	case ACL_TYPE_ACCESS:
		key = XATTR_NAME_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		key = XATTR_NAME_POSIX_ACL_DEFAULT;
		break;
	default:
		gossip_err("orangefs_get_acl: bogus value of type %d\n", type);
		return ERR_PTR(-EINVAL);
	}
	/*
	 * Rather than incurring a network call just to determine the exact
	 * length of the attribute, I just allocate a max length to save on
	 * the network call. Conceivably, we could pass NULL to
	 * orangefs_inode_getxattr() to probe the length of the value, but
	 * I don't do that for now.
	 */
	value = kmalloc(ORANGEFS_MAX_XATTR_VALUELEN, GFP_KERNEL);
	if (!value)
		return ERR_PTR(-ENOMEM);

	gossip_debug(GOSSIP_ACL_DEBUG,
		     "inode %pU, key %s, type %d\n",
		     get_khandle_from_ino(inode),
		     key,
		     type);
	ret = orangefs_inode_getxattr(inode, key, value,
				      ORANGEFS_MAX_XATTR_VALUELEN);
	/* if the key exists, convert it to an in-memory rep */
	if (ret > 0) {
		acl = posix_acl_from_xattr(&init_user_ns, value, ret);
	} else if (ret == -ENODATA || ret == -ENOSYS) {
		acl = NULL;
	} else {
		gossip_err("inode %pU retrieving acl's failed with error %d\n",
			   get_khandle_from_ino(inode),
			   ret);
		acl = ERR_PTR(ret);
	}
	/* kfree(NULL) is safe, so don't worry if value ever got used */
	kfree(value);
	return acl;
}

static int __orangefs_set_acl(struct inode *inode, struct posix_acl *acl,
			      int type)
{
	int error = 0;
	void *value = NULL;
	size_t size = 0;
	const char *name = NULL;

	switch (type) {
	case ACL_TYPE_ACCESS:
		name = XATTR_NAME_POSIX_ACL_ACCESS;
		break;
	case ACL_TYPE_DEFAULT:
		name = XATTR_NAME_POSIX_ACL_DEFAULT;
		break;
	default:
		gossip_err("%s: invalid type %d!\n", __func__, type);
		return -EINVAL;
	}

	gossip_debug(GOSSIP_ACL_DEBUG,
		     "%s: inode %pU, key %s type %d\n",
		     __func__, get_khandle_from_ino(inode),
		     name,
		     type);

	if (acl) {
		size = posix_acl_xattr_size(acl->a_count);
		value = kmalloc(size, GFP_KERNEL);
		if (!value)
			return -ENOMEM;

		error = posix_acl_to_xattr(&init_user_ns, acl, value, size);
		if (error < 0)
			goto out;
	}

	gossip_debug(GOSSIP_ACL_DEBUG,
		     "%s: name %s, value %p, size %zd, acl %p\n",
		     __func__, name, value, size, acl);
	/*
	 * Go ahead and set the extended attribute now. NOTE: Suppose acl
	 * was NULL, then value will be NULL and size will be 0 and that
	 * will xlate to a removexattr. However, we don't want removexattr
	 * complain if attributes does not exist.
	 */
	error = orangefs_inode_setxattr(inode, name, value, size, 0);

out:
	kfree(value);
	if (!error)
		set_cached_acl(inode, type, acl);
	return error;
}

int orangefs_set_acl(struct user_namespace *mnt_userns, struct inode *inode,
		     struct posix_acl *acl, int type)
{
	int error;
	struct iattr iattr;
	int rc;

	memset(&iattr, 0, sizeof iattr);

	if (type == ACL_TYPE_ACCESS && acl) {
		/*
		 * posix_acl_update_mode checks to see if the permissions
		 * described by the ACL can be encoded into the
		 * object's mode. If so, it sets "acl" to NULL
		 * and "mode" to the new desired value. It is up to
		 * us to propagate the new mode back to the server...
		 */
		error = posix_acl_update_mode(&init_user_ns, inode,
					      &iattr.ia_mode, &acl);
		if (error) {
			gossip_err("%s: posix_acl_update_mode err: %d\n",
				   __func__,
				   error);
			return error;
		}

		if (inode->i_mode != iattr.ia_mode)
			iattr.ia_valid = ATTR_MODE;

	}

	rc = __orangefs_set_acl(inode, acl, type);

	if (!rc && (iattr.ia_valid == ATTR_MODE))
		rc = __orangefs_setattr(inode, &iattr);

	return rc;
}

int orangefs_init_acl(struct inode *inode, struct inode *dir)
{
	struct posix_acl *default_acl, *acl;
	umode_t mode = inode->i_mode;
	struct iattr iattr;
	int error = 0;

	error = posix_acl_create(dir, &mode, &default_acl, &acl);
	if (error)
		return error;

	if (default_acl) {
		error = __orangefs_set_acl(inode, default_acl,
					   ACL_TYPE_DEFAULT);
		posix_acl_release(default_acl);
	} else {
		inode->i_default_acl = NULL;
	}

	if (acl) {
		if (!error)
			error = __orangefs_set_acl(inode, acl, ACL_TYPE_ACCESS);
		posix_acl_release(acl);
	} else {
		inode->i_acl = NULL;
	}

	/* If mode of the inode was changed, then do a forcible ->setattr */
	if (mode != inode->i_mode) {
		memset(&iattr, 0, sizeof iattr);
		inode->i_mode = mode;
		iattr.ia_mode = mode;
		iattr.ia_valid |= ATTR_MODE;
		__orangefs_setattr(inode, &iattr);
	}

	return error;
}