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
  13 static int hfsplus_security_getxattr(struct dentry *dentry, const char *name,
  14                                         void *buffer, size_t size, int type)
  15 {
  16         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  17         size_t len = strlen(name);
  18
  19         if (!strcmp(name, ""))
  20                 return -EINVAL;
  21
  22         if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
  23                 return -EOPNOTSUPP;
  24
  25         strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  26         strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
  27
  28         return hfsplus_getxattr(dentry, xattr_name, buffer, size);
  29 }
  30
  31 static int hfsplus_security_setxattr(struct dentry *dentry, const char *name,
  32                 const void *buffer, size_t size, int flags, int type)
  33 {
  34         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  35         size_t len = strlen(name);
  36
  37         if (!strcmp(name, ""))
  38                 return -EINVAL;
  39
  40         if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
  41                 return -EOPNOTSUPP;
  42
  43         strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  44         strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
  45
  46         return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
  47 }
  48
  49 static size_t hfsplus_security_listxattr(struct dentry *dentry, char *list,
  50                 size_t list_size, const char *name, size_t name_len, int type)
  51 {
  52         /*
  53          * This method is not used.
  54          * It is used hfsplus_listxattr() instead of generic_listxattr().
  55          */
  56         return -EOPNOTSUPP;
  57 }
  58
  59 static int hfsplus_initxattrs(struct inode *inode,
  60                                 const struct xattr *xattr_array,
  61                                 void *fs_info)
  62 {
  63         const struct xattr *xattr;
  64         char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
  65         size_t xattr_name_len;
  66         int err = 0;
  67
  68         for (xattr = xattr_array; xattr->name != NULL; xattr++) {
  69                 xattr_name_len = strlen(xattr->name);
  70
  71                 if (xattr_name_len == 0)
  72                         continue;
  73
  74                 if (xattr_name_len + XATTR_SECURITY_PREFIX_LEN >
  75                                 HFSPLUS_ATTR_MAX_STRLEN)
  76                         return -EOPNOTSUPP;
  77
  78                 strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  79                 strcpy(xattr_name +
  80                         XATTR_SECURITY_PREFIX_LEN, xattr->name);
  81                 memset(xattr_name +
  82                         XATTR_SECURITY_PREFIX_LEN + xattr_name_len, 0, 1);
  83
  84                 err = __hfsplus_setxattr(inode, xattr_name,
  85                                         xattr->value, xattr->value_len, 0);
  86                 if (err)
  87                         break;
  88         }
  89         return err;
  90 }
  91
  92 int hfsplus_init_security(struct inode *inode, struct inode *dir,
  93                                 const struct qstr *qstr)
  94 {
  95         return security_inode_init_security(inode, dir, qstr,
  96                                         &hfsplus_initxattrs, NULL);
  97 }
  98
  99 const struct xattr_handler hfsplus_xattr_security_handler = {
 100         .prefix = XATTR_SECURITY_PREFIX,
 101         .list   = hfsplus_security_listxattr,
 102         .get    = hfsplus_security_getxattr,
 103         .set    = hfsplus_security_setxattr,
 104 };