fs/ext3/xattr_security.c

   1 /*
   2  * linux/fs/ext3/xattr_security.c
   3  * Handler for storing security labels as extended attributes.
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/string.h>
   8 #include <linux/fs.h>
   9 #include <linux/smp_lock.h>
  10 #include <linux/ext3_jbd.h>
  11 #include <linux/ext3_fs.h>
  12 #include "xattr.h"
  13
  14 static size_t
  15 ext3_xattr_security_list(struct inode *inode, char *list, size_t list_size,
  16                          const char *name, size_t name_len)
  17 {
  18         const size_t prefix_len = sizeof(XATTR_SECURITY_PREFIX)-1;
  19         const size_t total_len = prefix_len + name_len + 1;
  20
  21
  22         if (list && total_len <= list_size) {
  23                 memcpy(list, XATTR_SECURITY_PREFIX, prefix_len);
  24                 memcpy(list+prefix_len, name, name_len);
  25                 list[prefix_len + name_len] = '\0';
  26         }
  27         return total_len;
  28 }
  29
  30 static int
  31 ext3_xattr_security_get(struct inode *inode, const char *name,
  32                        void *buffer, size_t size)
  33 {
  34         if (strcmp(name, "") == 0)
  35                 return -EINVAL;
  36         return ext3_xattr_get(inode, EXT3_XATTR_INDEX_SECURITY, name,
  37                               buffer, size);
  38 }
  39
  40 static int
  41 ext3_xattr_security_set(struct inode *inode, const char *name,
  42                        const void *value, size_t size, int flags)
  43 {
  44         if (strcmp(name, "") == 0)
  45                 return -EINVAL;
  46         return ext3_xattr_set(inode, EXT3_XATTR_INDEX_SECURITY, name,
  47                               value, size, flags);
  48 }
  49
  50 struct xattr_handler ext3_xattr_security_handler = {
  51         .prefix = XATTR_SECURITY_PREFIX,
  52         .list   = ext3_xattr_security_list,
  53         .get    = ext3_xattr_security_get,
  54         .set    = ext3_xattr_security_set,
  55 };