fs/hfsplus/xattr_security.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * linux/fs/hfsplus/xattr_trusted.c
   4  *
   5  * Vyacheslav Dubeyko <slava@dubeyko.com>
   6  *
   7  * Handler for storing security labels as extended attributes.
   8  */
   9
  10 #include <linux/security.h>
  11 #include <linux/nls.h>
  12
  13 #include "hfsplus_fs.h"
  14 #include "xattr.h"
  15
  16 static int hfsplus_security_getxattr(const struct xattr_handler *handler,
  17                                      struct dentry *unused, struct inode *inode,
  18                                      const char *name, void *buffer, size_t size)
  19 {
  20         return hfsplus_getxattr(inode, name, buffer, size,
  21                                 XATTR_SECURITY_PREFIX,
  22                                 XATTR_SECURITY_PREFIX_LEN);
  23 }
  24
  25 static int hfsplus_security_setxattr(const struct xattr_handler *handler,
  26                                      struct dentry *unused, struct inode *inode,
  27                                      const char *name, const void *buffer,
  28                                      size_t size, int flags)
  29 {
  30         return hfsplus_setxattr(inode, name, buffer, size, flags,
  31                                 XATTR_SECURITY_PREFIX,
  32                                 XATTR_SECURITY_PREFIX_LEN);
  33 }
  34
  35 static int hfsplus_initxattrs(struct inode *inode,
  36                                 const struct xattr *xattr_array,
  37                                 void *fs_info)
  38 {
  39         const struct xattr *xattr;
  40         char *xattr_name;
  41         int err = 0;
  42
  43         xattr_name = kmalloc(NLS_MAX_CHARSET_SIZE * HFSPLUS_ATTR_MAX_STRLEN + 1,
  44                 GFP_KERNEL);
  45         if (!xattr_name)
  46                 return -ENOMEM;
  47         for (xattr = xattr_array; xattr->name != NULL; xattr++) {
  48
  49                 if (!strcmp(xattr->name, ""))
  50                         continue;
  51
  52                 strcpy(xattr_name, XATTR_SECURITY_PREFIX);
  53                 strcpy(xattr_name +
  54                         XATTR_SECURITY_PREFIX_LEN, xattr->name);
  55                 memset(xattr_name +
  56                         XATTR_SECURITY_PREFIX_LEN + strlen(xattr->name), 0, 1);
  57
  58                 err = __hfsplus_setxattr(inode, xattr_name,
  59                                         xattr->value, xattr->value_len, 0);
  60                 if (err)
  61                         break;
  62         }
  63         kfree(xattr_name);
  64         return err;
  65 }
  66
  67 int hfsplus_init_security(struct inode *inode, struct inode *dir,
  68                                 const struct qstr *qstr)
  69 {
  70         return security_inode_init_security(inode, dir, qstr,
  71                                         &hfsplus_initxattrs, NULL);
  72 }
  73
  74 const struct xattr_handler hfsplus_xattr_security_handler = {
  75         .prefix = XATTR_SECURITY_PREFIX,
  76         .get    = hfsplus_security_getxattr,
  77         .set    = hfsplus_security_setxattr,
  78 };