Revision b5dc3c4800cc5c2c0b3c93a97eb4c7afa0aae49a authored by Martin Peschke on 22 August 2013, 15:45:38 UTC, committed by James Bottomley on 22 August 2013, 16:26:51 UTC
By popular demand, this patch brings back a couple of sysfs attributes
removed by commit 663e0890e31cb85f0cca5ac1faaee0d2d52880b5
"[SCSI] zfcp: remove access control tables interface".
The content has been irrelevant for years, but the files must be
there forever for whatever user space tools that may rely on them.

Since these files always return a constant value, a new stripped
down show-macro was required. Otherwise build warnings would have
been introduced.

Signed-off-by: Martin Peschke <mpeschke@linux.vnet.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
1 parent 924dd58
Raw File
xattr.c
/*
 *   fs/cifs/xattr.c
 *
 *   Copyright (c) International Business Machines  Corp., 2003, 2007
 *   Author(s): Steve French (sfrench@us.ibm.com)
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/fs.h>
#include <linux/posix_acl_xattr.h>
#include <linux/slab.h>
#include <linux/xattr.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"

#define MAX_EA_VALUE_SIZE 65535
#define CIFS_XATTR_DOS_ATTRIB "user.DosAttrib"
#define CIFS_XATTR_CIFS_ACL "system.cifs_acl"

/* BB need to add server (Samba e.g) support for security and trusted prefix */

int cifs_removexattr(struct dentry *direntry, const char *ea_name)
{
	int rc = -EOPNOTSUPP;
#ifdef CONFIG_CIFS_XATTR
	unsigned int xid;
	struct cifs_sb_info *cifs_sb;
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	struct super_block *sb;
	char *full_path = NULL;

	if (direntry == NULL)
		return -EIO;
	if (direntry->d_inode == NULL)
		return -EIO;
	sb = direntry->d_inode->i_sb;
	if (sb == NULL)
		return -EIO;

	cifs_sb = CIFS_SB(sb);
	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	pTcon = tlink_tcon(tlink);

	xid = get_xid();

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		rc = -ENOMEM;
		goto remove_ea_exit;
	}
	if (ea_name == NULL) {
		cifs_dbg(FYI, "Null xattr names not supported\n");
	} else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
		&& (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN))) {
		cifs_dbg(FYI,
			 "illegal xattr request %s (only user namespace supported)\n",
			 ea_name);
		/* BB what if no namespace prefix? */
		/* Should we just pass them to server, except for
		system and perhaps security prefixes? */
	} else {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
			goto remove_ea_exit;

		ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, NULL,
			(__u16)0, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	}
remove_ea_exit:
	kfree(full_path);
	free_xid(xid);
	cifs_put_tlink(tlink);
#endif
	return rc;
}

int cifs_setxattr(struct dentry *direntry, const char *ea_name,
		  const void *ea_value, size_t value_size, int flags)
{
	int rc = -EOPNOTSUPP;
#ifdef CONFIG_CIFS_XATTR
	unsigned int xid;
	struct cifs_sb_info *cifs_sb;
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	struct super_block *sb;
	char *full_path;

	if (direntry == NULL)
		return -EIO;
	if (direntry->d_inode == NULL)
		return -EIO;
	sb = direntry->d_inode->i_sb;
	if (sb == NULL)
		return -EIO;

	cifs_sb = CIFS_SB(sb);
	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	pTcon = tlink_tcon(tlink);

	xid = get_xid();

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		rc = -ENOMEM;
		goto set_ea_exit;
	}
	/* return dos attributes as pseudo xattr */
	/* return alt name if available as pseudo attr */

	/* if proc/fs/cifs/streamstoxattr is set then
		search server for EAs or streams to
		returns as xattrs */
	if (value_size > MAX_EA_VALUE_SIZE) {
		cifs_dbg(FYI, "size of EA value too large\n");
		rc = -EOPNOTSUPP;
		goto set_ea_exit;
	}

	if (ea_name == NULL) {
		cifs_dbg(FYI, "Null xattr names not supported\n");
	} else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
		   == 0) {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
			goto set_ea_exit;
		if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0)
			cifs_dbg(FYI, "attempt to set cifs inode metadata\n");

		ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
			(__u16)value_size, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	} else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN)
		   == 0) {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
			goto set_ea_exit;

		ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
		rc = CIFSSMBSetEA(xid, pTcon, full_path, ea_name, ea_value,
			(__u16)value_size, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	} else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
			strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
#ifdef CONFIG_CIFS_ACL
		struct cifs_ntsd *pacl;
		pacl = kmalloc(value_size, GFP_KERNEL);
		if (!pacl) {
			rc = -ENOMEM;
		} else {
			memcpy(pacl, ea_value, value_size);
			rc = set_cifs_acl(pacl, value_size,
				direntry->d_inode, full_path, CIFS_ACL_DACL);
			if (rc == 0) /* force revalidate of the inode */
				CIFS_I(direntry->d_inode)->time = 0;
			kfree(pacl);
		}
#else
		cifs_dbg(FYI, "Set CIFS ACL not supported yet\n");
#endif /* CONFIG_CIFS_ACL */
	} else {
		int temp;
		temp = strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
			strlen(POSIX_ACL_XATTR_ACCESS));
		if (temp == 0) {
#ifdef CONFIG_CIFS_POSIX
			if (sb->s_flags & MS_POSIXACL)
				rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
					ea_value, (const int)value_size,
					ACL_TYPE_ACCESS, cifs_sb->local_nls,
					cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);
			cifs_dbg(FYI, "set POSIX ACL rc %d\n", rc);
#else
			cifs_dbg(FYI, "set POSIX ACL not supported\n");
#endif
		} else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
				   strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
#ifdef CONFIG_CIFS_POSIX
			if (sb->s_flags & MS_POSIXACL)
				rc = CIFSSMBSetPosixACL(xid, pTcon, full_path,
					ea_value, (const int)value_size,
					ACL_TYPE_DEFAULT, cifs_sb->local_nls,
					cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);
			cifs_dbg(FYI, "set POSIX default ACL rc %d\n", rc);
#else
			cifs_dbg(FYI, "set default POSIX ACL not supported\n");
#endif
		} else {
			cifs_dbg(FYI, "illegal xattr request %s (only user namespace supported)\n",
				 ea_name);
		  /* BB what if no namespace prefix? */
		  /* Should we just pass them to server, except for
		  system and perhaps security prefixes? */
		}
	}

set_ea_exit:
	kfree(full_path);
	free_xid(xid);
	cifs_put_tlink(tlink);
#endif
	return rc;
}

ssize_t cifs_getxattr(struct dentry *direntry, const char *ea_name,
	void *ea_value, size_t buf_size)
{
	ssize_t rc = -EOPNOTSUPP;
#ifdef CONFIG_CIFS_XATTR
	unsigned int xid;
	struct cifs_sb_info *cifs_sb;
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	struct super_block *sb;
	char *full_path;

	if (direntry == NULL)
		return -EIO;
	if (direntry->d_inode == NULL)
		return -EIO;
	sb = direntry->d_inode->i_sb;
	if (sb == NULL)
		return -EIO;

	cifs_sb = CIFS_SB(sb);
	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	pTcon = tlink_tcon(tlink);

	xid = get_xid();

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		rc = -ENOMEM;
		goto get_ea_exit;
	}
	/* return dos attributes as pseudo xattr */
	/* return alt name if available as pseudo attr */
	if (ea_name == NULL) {
		cifs_dbg(FYI, "Null xattr names not supported\n");
	} else if (strncmp(ea_name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN)
		   == 0) {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
			goto get_ea_exit;

		if (strncmp(ea_name, CIFS_XATTR_DOS_ATTRIB, 14) == 0) {
			cifs_dbg(FYI, "attempt to query cifs inode metadata\n");
			/* revalidate/getattr then populate from inode */
		} /* BB add else when above is implemented */
		ea_name += XATTR_USER_PREFIX_LEN; /* skip past user. prefix */
		rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
			buf_size, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	} else if (strncmp(ea_name, XATTR_OS2_PREFIX, XATTR_OS2_PREFIX_LEN) == 0) {
		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
			goto get_ea_exit;

		ea_name += XATTR_OS2_PREFIX_LEN; /* skip past os2. prefix */
		rc = CIFSSMBQAllEAs(xid, pTcon, full_path, ea_name, ea_value,
			buf_size, cifs_sb->local_nls,
			cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
	} else if (strncmp(ea_name, POSIX_ACL_XATTR_ACCESS,
			  strlen(POSIX_ACL_XATTR_ACCESS)) == 0) {
#ifdef CONFIG_CIFS_POSIX
		if (sb->s_flags & MS_POSIXACL)
			rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
				ea_value, buf_size, ACL_TYPE_ACCESS,
				cifs_sb->local_nls,
				cifs_sb->mnt_cifs_flags &
					CIFS_MOUNT_MAP_SPECIAL_CHR);
#else
		cifs_dbg(FYI, "Query POSIX ACL not supported yet\n");
#endif /* CONFIG_CIFS_POSIX */
	} else if (strncmp(ea_name, POSIX_ACL_XATTR_DEFAULT,
			  strlen(POSIX_ACL_XATTR_DEFAULT)) == 0) {
#ifdef CONFIG_CIFS_POSIX
		if (sb->s_flags & MS_POSIXACL)
			rc = CIFSSMBGetPosixACL(xid, pTcon, full_path,
				ea_value, buf_size, ACL_TYPE_DEFAULT,
				cifs_sb->local_nls,
				cifs_sb->mnt_cifs_flags &
					CIFS_MOUNT_MAP_SPECIAL_CHR);
#else
		cifs_dbg(FYI, "Query POSIX default ACL not supported yet\n");
#endif /* CONFIG_CIFS_POSIX */
	} else if (strncmp(ea_name, CIFS_XATTR_CIFS_ACL,
				strlen(CIFS_XATTR_CIFS_ACL)) == 0) {
#ifdef CONFIG_CIFS_ACL
			u32 acllen;
			struct cifs_ntsd *pacl;

			pacl = get_cifs_acl(cifs_sb, direntry->d_inode,
						full_path, &acllen);
			if (IS_ERR(pacl)) {
				rc = PTR_ERR(pacl);
				cifs_dbg(VFS, "%s: error %zd getting sec desc\n",
					 __func__, rc);
			} else {
				if (ea_value) {
					if (acllen > buf_size)
						acllen = -ERANGE;
					else
						memcpy(ea_value, pacl, acllen);
				}
				rc = acllen;
				kfree(pacl);
			}
#else
			cifs_dbg(FYI, "Query CIFS ACL not supported yet\n");
#endif /* CONFIG_CIFS_ACL */
	} else if (strncmp(ea_name,
		  XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) == 0) {
		cifs_dbg(FYI, "Trusted xattr namespace not supported yet\n");
	} else if (strncmp(ea_name,
		  XATTR_SECURITY_PREFIX, XATTR_SECURITY_PREFIX_LEN) == 0) {
		cifs_dbg(FYI, "Security xattr namespace not supported yet\n");
	} else
		cifs_dbg(FYI,
			 "illegal xattr request %s (only user namespace supported)\n",
			 ea_name);

	/* We could add an additional check for streams ie
	    if proc/fs/cifs/streamstoxattr is set then
		search server for EAs or streams to
		returns as xattrs */

	if (rc == -EINVAL)
		rc = -EOPNOTSUPP;

get_ea_exit:
	kfree(full_path);
	free_xid(xid);
	cifs_put_tlink(tlink);
#endif
	return rc;
}

ssize_t cifs_listxattr(struct dentry *direntry, char *data, size_t buf_size)
{
	ssize_t rc = -EOPNOTSUPP;
#ifdef CONFIG_CIFS_XATTR
	unsigned int xid;
	struct cifs_sb_info *cifs_sb;
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	struct super_block *sb;
	char *full_path;

	if (direntry == NULL)
		return -EIO;
	if (direntry->d_inode == NULL)
		return -EIO;
	sb = direntry->d_inode->i_sb;
	if (sb == NULL)
		return -EIO;

	cifs_sb = CIFS_SB(sb);
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_XATTR)
		return -EOPNOTSUPP;

	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	pTcon = tlink_tcon(tlink);

	xid = get_xid();

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		rc = -ENOMEM;
		goto list_ea_exit;
	}
	/* return dos attributes as pseudo xattr */
	/* return alt name if available as pseudo attr */

	/* if proc/fs/cifs/streamstoxattr is set then
		search server for EAs or streams to
		returns as xattrs */
	rc = CIFSSMBQAllEAs(xid, pTcon, full_path, NULL, data,
				buf_size, cifs_sb->local_nls,
				cifs_sb->mnt_cifs_flags &
					CIFS_MOUNT_MAP_SPECIAL_CHR);

list_ea_exit:
	kfree(full_path);
	free_xid(xid);
	cifs_put_tlink(tlink);
#endif
	return rc;
}
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