Allow requests for security.* and trusted.* xattr name spaces to pass through to server. The new files are 99% cut and paste from fs/9p/xattr_user.c with the namespaces changed. It has the intended effect in superficial testing. I do not know much detail about how these namespaces are used, but passing them through to the server, which can decide whether to handle them or not, seems reasonable. I want to support a use case where an ext4 file system is mounted via 9P, then re-exported via samba to windows clients in a cluster. Windows wants to store xattrs such as security.NTACL. This works when ext4 directly backs samba, but not when 9P is inserted. This use case is documented here: http://code.google.com/p/diod/issues/detail?id=95 Signed-off-by: Jim Garlick <garlick@llnl.gov> Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
		
			
				
	
	
		
			80 lines
		
	
	
	
		
			2.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			80 lines
		
	
	
	
		
			2.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
/*
 | 
						|
 * Copyright IBM Corporation, 2010
 | 
						|
 * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
 | 
						|
 *
 | 
						|
 * This program is free software; you can redistribute it and/or modify it
 | 
						|
 * under the terms of version 2.1 of the GNU Lesser General Public License
 | 
						|
 * as published by the Free Software Foundation.
 | 
						|
 *
 | 
						|
 * This program is distributed in the hope that it would be useful, but
 | 
						|
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 | 
						|
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 | 
						|
 *
 | 
						|
 */
 | 
						|
 | 
						|
 | 
						|
#include <linux/module.h>
 | 
						|
#include <linux/string.h>
 | 
						|
#include <linux/fs.h>
 | 
						|
#include <linux/slab.h>
 | 
						|
#include "xattr.h"
 | 
						|
 | 
						|
static int v9fs_xattr_security_get(struct dentry *dentry, const char *name,
 | 
						|
			void *buffer, size_t size, int type)
 | 
						|
{
 | 
						|
	int retval;
 | 
						|
	char *full_name;
 | 
						|
	size_t name_len;
 | 
						|
	size_t prefix_len = XATTR_SECURITY_PREFIX_LEN;
 | 
						|
 | 
						|
	if (name == NULL)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	if (strcmp(name, "") == 0)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	name_len = strlen(name);
 | 
						|
	full_name = kmalloc(prefix_len + name_len + 1 , GFP_KERNEL);
 | 
						|
	if (!full_name)
 | 
						|
		return -ENOMEM;
 | 
						|
	memcpy(full_name, XATTR_SECURITY_PREFIX, prefix_len);
 | 
						|
	memcpy(full_name+prefix_len, name, name_len);
 | 
						|
	full_name[prefix_len + name_len] = '\0';
 | 
						|
 | 
						|
	retval = v9fs_xattr_get(dentry, full_name, buffer, size);
 | 
						|
	kfree(full_name);
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
static int v9fs_xattr_security_set(struct dentry *dentry, const char *name,
 | 
						|
			const void *value, size_t size, int flags, int type)
 | 
						|
{
 | 
						|
	int retval;
 | 
						|
	char *full_name;
 | 
						|
	size_t name_len;
 | 
						|
	size_t prefix_len = XATTR_SECURITY_PREFIX_LEN;
 | 
						|
 | 
						|
	if (name == NULL)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	if (strcmp(name, "") == 0)
 | 
						|
		return -EINVAL;
 | 
						|
 | 
						|
	name_len = strlen(name);
 | 
						|
	full_name = kmalloc(prefix_len + name_len + 1 , GFP_KERNEL);
 | 
						|
	if (!full_name)
 | 
						|
		return -ENOMEM;
 | 
						|
	memcpy(full_name, XATTR_SECURITY_PREFIX, prefix_len);
 | 
						|
	memcpy(full_name + prefix_len, name, name_len);
 | 
						|
	full_name[prefix_len + name_len] = '\0';
 | 
						|
 | 
						|
	retval = v9fs_xattr_set(dentry, full_name, value, size, flags);
 | 
						|
	kfree(full_name);
 | 
						|
	return retval;
 | 
						|
}
 | 
						|
 | 
						|
struct xattr_handler v9fs_xattr_security_handler = {
 | 
						|
	.prefix	= XATTR_SECURITY_PREFIX,
 | 
						|
	.get	= v9fs_xattr_security_get,
 | 
						|
	.set	= v9fs_xattr_security_set,
 | 
						|
};
 |