o Change the API and ABI of the Extended Attribute kernel interfaces to

  introduce a new argument, "namespace", rather than relying on a first-
  character namespace indicator.  This is in line with more recent
  thinking on EA interfaces on various mailing lists, including the
  posix1e, Linux acl-devel, and trustedbsd-discuss forums.  Two namespaces
  are defined by default, EXTATTR_NAMESPACE_SYSTEM and
  EXTATTR_NAMESPACE_USER, where the primary distinction lies in the
  access control model: user EAs are accessible based on the normal
  MAC and DAC file/directory protections, and system attributes are
  limited to kernel-originated or appropriately privileged userland
  requests.

o These API changes occur at several levels: the namespace argument is
  introduced in the extattr_{get,set}_file() system call interfaces,
  at the vnode operation level in the vop_{get,set}extattr() interfaces,
  and in the UFS extended attribute implementation.  Changes are also
  introduced in the VFS extattrctl() interface (system call, VFS,
  and UFS implementation), where the arguments are modified to include
  a namespace field, as well as modified to advoid direct access to
  userspace variables from below the VFS layer (in the style of recent
  changes to mount by adrian@FreeBSD.org).  This required some cleanup
  and bug fixing regarding VFS locks and the VFS interface, as a vnode
  pointer may now be optionally submitted to the VFS_EXTATTRCTL()
  call.  Updated documentation for the VFS interface will be committed
  shortly.

o In the near future, the auto-starting feature will be updated to
  search two sub-directories to the ".attribute" directory in appropriate
  file systems: "user" and "system" to locate attributes intended for
  those namespaces, as the single filename is no longer sufficient
  to indicate what namespace the attribute is intended for.  Until this
  is committed, all attributes auto-started by UFS will be placed in
  the EXTATTR_NAMESPACE_SYSTEM namespace.

o The default POSIX.1e attribute names for ACLs and Capabilities have
  been updated to no longer include the '$' in their filename.  As such,
  if you're using these features, you'll need to rename the attribute
  backing files to the same names without '$' symbols in front.

o Note that these changes will require changes in userland, which will
  be committed shortly.  These include modifications to the extended
  attribute utilities, as well as to libutil for new namespace
  string conversion routines.  Once the matching userland changes are
  committed, a buildworld is recommended to update all the necessary
  include files and verify that the kernel and userland environments
  are in sync.  Note: If you do not use extended attributes (most people
  won't), upgrading is not imperative although since the system call
  API has changed, the new userland extended attribute code will no longer
  compile with old include files.

o Couple of minor cleanups while I'm there: make more code compilation
  conditional on FFS_EXTATTR, which should recover a bit of space on
  kernels running without EA's, as well as update copyright dates.

Obtained from:	TrustedBSD Project

1 files changed, 15 insertions, 7 deletions

diff --git a/sys/sys/extattr.h b/sys/sys/extattr.h
index d03d4fb..4b545da 100644
--- a/sys/sys/extattr.h
+++ b/sys/sys/extattr.h
@@ -1,5 +1,5 @@
 /*-
- * Copyright (c) 1999 Robert N. M. Watson
+ * Copyright (c) 1999, 2000, 2001 Robert N. M. Watson
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -41,6 +41,12 @@
 
 #ifndef _SYS_EXTATTR_H_
 #define	_SYS_EXTATTR_H_
+
+#define	EXTATTR_NAMESPACE_USER		0x00000001
+#define	EXTATTR_NAMESPACE_USER_STRING	"user"
+#define	EXTATTR_NAMESPACE_SYSTEM	0x00000002
+#define	EXTATTR_NAMESPACE_SYSTEM_STRING	"system"
+
 #ifdef _KERNEL
 
 #define	EXTATTR_MAXNAMELEN	NAME_MAX
@@ -51,12 +57,14 @@
 struct iovec;
 
 __BEGIN_DECLS
-int	extattrctl(const char *path, int cmd, const char *attrname, char *arg);
-int	extattr_delete_file(const char *path, const char *attrname);
-int	extattr_get_file(const char *path, const char *attrname,
-	    struct iovec *iovp, unsigned iovcnt);
-int	extattr_set_file(const char *path, const char *attrname,
-	    struct iovec *iovp, unsigned iovcnt);
+int	extattrctl(const char *path, int cmd, const char *filename,
+	    int namespace, const char *attrname);
+int	extattr_delete_file(const char *path, int namespace,
+	    const char *attrname);
+int	extattr_get_file(const char *path, int namespace,
+	    const char *attrname, struct iovec *iovp, unsigned iovcnt);
+int	extattr_set_file(const char *path, int namespace,
+	    const char *attrname, struct iovec *iovp, unsigned iovcnt);
 __END_DECLS
 
 #endif /* !_KERNEL */