fs/hfsplus/xattr_security.c

   1 /*
   2  * linux/fs/hfsplus/xattr_trusted.c
   3  *
   4  * Vyacheslav Dubeyko <slava@dubeyko.com>
   5  *
   6  * Handler for storing security labels as extended attributes.
   7  */
   8
   9 #include <linux/security.h>
  10 #include "hfsplus_fs.h"
  11 #include "xattr.h"
  12 #include "acl.h"
  13
  14 static int hfsplus_security_getxattr(struct dentry *dentry, const char *name,
  15                                         void *buffer, size_t size, int type)
  16 {
  17         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  18         size_t len = strlen(name);
  19
  20         if (!strcmp(name, ""))
  21                 return -EINVAL;
  22
  23         if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
  24                 return -EOPNOTSUPP;
  25
  26         strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  27         strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
  28
  29         return hfsplus_getxattr(dentry, xattr_name, buffer, size);
  30 }
  31
  32 static int hfsplus_security_setxattr(struct dentry *dentry, const char *name,
  33                 const void *buffer, size_t size, int flags, int type)
  34 {
  35         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  36         size_t len = strlen(name);
  37
  38         if (!strcmp(name, ""))
  39                 return -EINVAL;
  40
  41         if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
  42                 return -EOPNOTSUPP;
  43
  44         strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  45         strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
  46
  47         return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
  48 }
  49
  50 static size_t hfsplus_security_listxattr(struct dentry *dentry, char *list,
  51                 size_t list_size, const char *name, size_t name_len, int type)
  52 {
  53         /*
  54          * This method is not used.
  55          * It is used hfsplus_listxattr() instead of generic_listxattr().
  56          */
  57         return -EOPNOTSUPP;
  58 }
  59
  60 static int hfsplus_initxattrs(struct inode *inode,
  61                                 const struct xattr *xattr_array,
  62                                 void *fs_info)
  63 {
  64         const struct xattr *xattr;
  65         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  66         size_t xattr_name_len;
  67         int err = 0;
  68
  69         for (xattr = xattr_array; xattr->name != NULL; xattr++) {
  70                 xattr_name_len = strlen(xattr->name);
  71
  72                 if (xattr_name_len == 0)
  73                         continue;
  74
  75                 if (xattr_name_len + XATTR_SECURITY_PREFIX_LEN >
  76                                 HFSPLUS_ATTR_MAX_STRLEN)
  77                         return -EOPNOTSUPP;
  78
  79                 strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  80                 strcpy(xattr_name +
  81                         XATTR_SECURITY_PREFIX_LEN, xattr->name);
  82                 memset(xattr_name +
  83                         XATTR_SECURITY_PREFIX_LEN + xattr_name_len, 0, 1);
  84
  85                 err = __hfsplus_setxattr(inode, xattr_name,
  86                                         xattr->value, xattr->value_len, 0);
  87                 if (err)
  88                         break;
  89         }
  90         return err;
  91 }
  92
  93 int hfsplus_init_security(struct inode *inode, struct inode *dir,
  94                                 const struct qstr *qstr)
  95 {
  96         return security_inode_init_security(inode, dir, qstr,
  97                                         &hfsplus_initxattrs, NULL);
  98 }
  99
 100 int hfsplus_init_inode_security(struct inode *inode,
 101                                                 struct inode *dir,
 102                                                 const struct qstr *qstr)
 103 {
 104         int err;
 105
 106         err = hfsplus_init_posix_acl(inode, dir);
 107         if (!err)
 108                 err = hfsplus_init_security(inode, dir, qstr);
 109         return err;
 110 }
 111
 112 const struct xattr_handler hfsplus_xattr_security_handler = {
 113         .prefix = XATTR_SECURITY_PREFIX,
 114         .list   = hfsplus_security_listxattr,
 115         .get    = hfsplus_security_getxattr,
 116         .set    = hfsplus_security_setxattr,
 117 };