Blame view

kernel/linux-imx6_3.14.28/fs/reiserfs/xattr_security.c 2.93 KB
6b13f685e   김민수   BSP 최초 추가
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
  #include "reiserfs.h"
  #include <linux/errno.h>
  #include <linux/fs.h>
  #include <linux/pagemap.h>
  #include <linux/xattr.h>
  #include <linux/slab.h>
  #include "xattr.h"
  #include <linux/security.h>
  #include <asm/uaccess.h>
  
  static int
  security_get(struct dentry *dentry, const char *name, void *buffer, size_t size,
  		int handler_flags)
  {
  	if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
  		return -EINVAL;
  
  	if (IS_PRIVATE(dentry->d_inode))
  		return -EPERM;
  
  	return reiserfs_xattr_get(dentry->d_inode, name, buffer, size);
  }
  
  static int
  security_set(struct dentry *dentry, const char *name, const void *buffer,
  	     size_t size, int flags, int handler_flags)
  {
  	if (strlen(name) < sizeof(XATTR_SECURITY_PREFIX))
  		return -EINVAL;
  
  	if (IS_PRIVATE(dentry->d_inode))
  		return -EPERM;
  
  	return reiserfs_xattr_set(dentry->d_inode, name, buffer, size, flags);
  }
  
  static size_t security_list(struct dentry *dentry, char *list, size_t list_len,
  			    const char *name, size_t namelen, int handler_flags)
  {
  	const size_t len = namelen + 1;
  
  	if (IS_PRIVATE(dentry->d_inode))
  		return 0;
  
  	if (list && len <= list_len) {
  		memcpy(list, name, namelen);
  		list[namelen] = '\0';
  	}
  
  	return len;
  }
  
  /* Initializes the security context for a new inode and returns the number
   * of blocks needed for the transaction. If successful, reiserfs_security
   * must be released using reiserfs_security_free when the caller is done. */
  int reiserfs_security_init(struct inode *dir, struct inode *inode,
  			   const struct qstr *qstr,
  			   struct reiserfs_security_handle *sec)
  {
  	int blocks = 0;
  	int error;
  
  	sec->name = NULL;
  
  	/* Don't add selinux attributes on xattrs - they'll never get used */
  	if (IS_PRIVATE(dir))
  		return 0;
  
  	error = security_old_inode_init_security(inode, dir, qstr, &sec->name,
  						 &sec->value, &sec->length);
  	if (error) {
  		if (error == -EOPNOTSUPP)
  			error = 0;
  
  		sec->name = NULL;
  		sec->value = NULL;
  		sec->length = 0;
  		return error;
  	}
  
  	if (sec->length && reiserfs_xattrs_initialized(inode->i_sb)) {
  		blocks = reiserfs_xattr_jcreate_nblocks(inode) +
  			 reiserfs_xattr_nblocks(inode, sec->length);
  		/* We don't want to count the directories twice if we have
  		 * a default ACL. */
  		REISERFS_I(inode)->i_flags |= i_has_xattr_dir;
  	}
  	return blocks;
  }
  
  int reiserfs_security_write(struct reiserfs_transaction_handle *th,
  			    struct inode *inode,
  			    struct reiserfs_security_handle *sec)
  {
  	int error;
  	if (strlen(sec->name) < sizeof(XATTR_SECURITY_PREFIX))
  		return -EINVAL;
  
  	error = reiserfs_xattr_set_handle(th, inode, sec->name, sec->value,
  					  sec->length, XATTR_CREATE);
  	if (error == -ENODATA || error == -EOPNOTSUPP)
  		error = 0;
  
  	return error;
  }
  
  void reiserfs_security_free(struct reiserfs_security_handle *sec)
  {
  	kfree(sec->name);
  	kfree(sec->value);
  	sec->name = NULL;
  	sec->value = NULL;
  }
  
  const struct xattr_handler reiserfs_xattr_security_handler = {
  	.prefix = XATTR_SECURITY_PREFIX,
  	.get = security_get,
  	.set = security_set,
  	.list = security_list,
  };