hfsplus: rework functionality of getting, setting and deleting of extended attributes

[cascardo/linux.git] / fs / hfsplus / xattr_security.c

diff --git a/fs/hfsplus/xattr_security.c b/fs/hfsplus/xattr_security.c
new file mode 100644 (file)
index 0000000..83b842f
--- /dev/null
+++ b/fs/hfsplus/xattr_security.c
@@ -0,0 +1,104 @@
+/*
+ * linux/fs/hfsplus/xattr_trusted.c
+ *
+ * Vyacheslav Dubeyko <slava@dubeyko.com>
+ *
+ * Handler for storing security labels as extended attributes.
+ */
+
+#include <linux/security.h>
+#include "hfsplus_fs.h"
+#include "xattr.h"
+
+static int hfsplus_security_getxattr(struct dentry *dentry, const char *name,
+                                       void *buffer, size_t size, int type)
+{
+       char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+       size_t len = strlen(name);
+
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+               return -EOPNOTSUPP;
+
+       strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+       strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
+
+       return hfsplus_getxattr(dentry, xattr_name, buffer, size);
+}
+
+static int hfsplus_security_setxattr(struct dentry *dentry, const char *name,
+               const void *buffer, size_t size, int flags, int type)
+{
+       char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+       size_t len = strlen(name);
+
+       if (!strcmp(name, ""))
+               return -EINVAL;
+
+       if (len + XATTR_SECURITY_PREFIX_LEN > HFSPLUS_ATTR_MAX_STRLEN)
+               return -EOPNOTSUPP;
+
+       strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+       strcpy(xattr_name + XATTR_SECURITY_PREFIX_LEN, name);
+
+       return hfsplus_setxattr(dentry, xattr_name, buffer, size, flags);
+}
+
+static size_t hfsplus_security_listxattr(struct dentry *dentry, char *list,
+               size_t list_size, const char *name, size_t name_len, int type)
+{
+       /*
+        * This method is not used.
+        * It is used hfsplus_listxattr() instead of generic_listxattr().
+        */
+       return -EOPNOTSUPP;
+}
+
+static int hfsplus_initxattrs(struct inode *inode,
+                               const struct xattr *xattr_array,
+                               void *fs_info)
+{
+       const struct xattr *xattr;
+       char xattr_name[HFSPLUS_ATTR_MAX_STRLEN + 1] = {0};
+       size_t xattr_name_len;
+       int err = 0;
+
+       for (xattr = xattr_array; xattr->name != NULL; xattr++) {
+               xattr_name_len = strlen(xattr->name);
+
+               if (xattr_name_len == 0)
+                       continue;
+
+               if (xattr_name_len + XATTR_SECURITY_PREFIX_LEN >
+                               HFSPLUS_ATTR_MAX_STRLEN)
+                       return -EOPNOTSUPP;
+
+               strcpy(xattr_name, XATTR_SECURITY_PREFIX);
+               strcpy(xattr_name +
+                       XATTR_SECURITY_PREFIX_LEN, xattr->name);
+               memset(xattr_name +
+                       XATTR_SECURITY_PREFIX_LEN + xattr_name_len, 0, 1);
+
+               err = __hfsplus_setxattr(inode, xattr_name,
+                                       xattr->value, xattr->value_len, 0);
+               if (err)
+                       break;
+       }
+       return err;
+}
+
+int hfsplus_init_security(struct inode *inode, struct inode *dir,
+                               const struct qstr *qstr)
+{
+       return security_inode_init_security(inode, dir, qstr,
+                                       &hfsplus_initxattrs, NULL);
+}
+
+const struct xattr_handler hfsplus_xattr_security_handler = {
+       .prefix = XATTR_SECURITY_PREFIX,
+       .list   = hfsplus_security_listxattr,
+       .get    = hfsplus_security_getxattr,
+       .set    = hfsplus_security_setxattr,
+};