mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-26 10:49:33 +00:00
![Steve French](/assets/img/avatar_default.png)
SMB2 is the followon to the CIFS (and SMB) protocols and the default for Windows since Windows Vista, and also now implemented by various non-Windows servers. SMB2 is more secure, has various performance advantages, including larger i/o sizes, flow control, better caching model and more. SMB2 also resolves some scalability limits in the CIFS protocol and adds many new features while being much simpler (only a few dozen commands instead of hundreds) and since the protocol is clearer it is also more consistently implemented across servers and thus easier to optimize. After much discussion with Jeff Layton, Jeremy Allison and others at Connectathon, we decided to move the SMB2 code from a distinct .ko and fstype into distinct C files that optionally build in cifs.ko. As a result the Kconfig gets simpler. To avoid destabilizing CIFS, the SMB2 code is going to be moved into its own experimental CONFIG_CIFS_SMB2 ifdef as it is merged and rereviewed. The changes to stable CIFS (builds with the SMB2 ifdef off) are expected to be fairly small. Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Steve French <sfrench@us.ibm.com> Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by: Steve French <sfrench@us.ibm.com>
180 lines
7.2 KiB
Text
180 lines
7.2 KiB
Text
config CIFS
|
|
tristate "CIFS support (advanced network filesystem, SMBFS successor)"
|
|
depends on INET
|
|
select NLS
|
|
select CRYPTO
|
|
select CRYPTO_MD4
|
|
select CRYPTO_MD5
|
|
select CRYPTO_HMAC
|
|
select CRYPTO_ARC4
|
|
select CRYPTO_ECB
|
|
select CRYPTO_DES
|
|
help
|
|
This is the client VFS module for the Common Internet File System
|
|
(CIFS) protocol which is the successor to the Server Message Block
|
|
(SMB) protocol, the native file sharing mechanism for most early
|
|
PC operating systems. The CIFS protocol is fully supported by
|
|
file servers such as Windows 2000 (including Windows 2003, NT 4
|
|
and Windows XP) as well by Samba (which provides excellent CIFS
|
|
server support for Linux and many other operating systems). Limited
|
|
support for OS/2 and Windows ME and similar servers is provided as
|
|
well.
|
|
|
|
The cifs module provides an advanced network file system
|
|
client for mounting to CIFS compliant servers. It includes
|
|
support for DFS (hierarchical name space), secure per-user
|
|
session establishment via Kerberos or NTLM or NTLMv2,
|
|
safe distributed caching (oplock), optional packet
|
|
signing, Unicode and other internationalization improvements.
|
|
If you need to mount to Samba or Windows from this machine, say Y.
|
|
|
|
config CIFS_STATS
|
|
bool "CIFS statistics"
|
|
depends on CIFS
|
|
help
|
|
Enabling this option will cause statistics for each server share
|
|
mounted by the cifs client to be displayed in /proc/fs/cifs/Stats
|
|
|
|
config CIFS_STATS2
|
|
bool "Extended statistics"
|
|
depends on CIFS_STATS
|
|
help
|
|
Enabling this option will allow more detailed statistics on SMB
|
|
request timing to be displayed in /proc/fs/cifs/DebugData and also
|
|
allow optional logging of slow responses to dmesg (depending on the
|
|
value of /proc/fs/cifs/cifsFYI, see fs/cifs/README for more details).
|
|
These additional statistics may have a minor effect on performance
|
|
and memory utilization.
|
|
|
|
Unless you are a developer or are doing network performance analysis
|
|
or tuning, say N.
|
|
|
|
config CIFS_WEAK_PW_HASH
|
|
bool "Support legacy servers which use weaker LANMAN security"
|
|
depends on CIFS
|
|
help
|
|
Modern CIFS servers including Samba and most Windows versions
|
|
(since 1997) support stronger NTLM (and even NTLMv2 and Kerberos)
|
|
security mechanisms. These hash the password more securely
|
|
than the mechanisms used in the older LANMAN version of the
|
|
SMB protocol but LANMAN based authentication is needed to
|
|
establish sessions with some old SMB servers.
|
|
|
|
Enabling this option allows the cifs module to mount to older
|
|
LANMAN based servers such as OS/2 and Windows 95, but such
|
|
mounts may be less secure than mounts using NTLM or more recent
|
|
security mechanisms if you are on a public network. Unless you
|
|
have a need to access old SMB servers (and are on a private
|
|
network) you probably want to say N. Even if this support
|
|
is enabled in the kernel build, LANMAN authentication will not be
|
|
used automatically. At runtime LANMAN mounts are disabled but
|
|
can be set to required (or optional) either in
|
|
/proc/fs/cifs (see fs/cifs/README for more detail) or via an
|
|
option on the mount command. This support is disabled by
|
|
default in order to reduce the possibility of a downgrade
|
|
attack.
|
|
|
|
If unsure, say N.
|
|
|
|
config CIFS_UPCALL
|
|
bool "Kerberos/SPNEGO advanced session setup"
|
|
depends on CIFS && KEYS
|
|
select DNS_RESOLVER
|
|
help
|
|
Enables an upcall mechanism for CIFS which accesses userspace helper
|
|
utilities to provide SPNEGO packaged (RFC 4178) Kerberos tickets
|
|
which are needed to mount to certain secure servers (for which more
|
|
secure Kerberos authentication is required). If unsure, say N.
|
|
|
|
config CIFS_XATTR
|
|
bool "CIFS extended attributes"
|
|
depends on CIFS
|
|
help
|
|
Extended attributes are name:value pairs associated with inodes by
|
|
the kernel or by users (see the attr(5) manual page, or visit
|
|
<http://acl.bestbits.at/> for details). CIFS maps the name of
|
|
extended attributes beginning with the user namespace prefix
|
|
to SMB/CIFS EAs. EAs are stored on Windows servers without the
|
|
user namespace prefix, but their names are seen by Linux cifs clients
|
|
prefaced by the user namespace prefix. The system namespace
|
|
(used by some filesystems to store ACLs) is not supported at
|
|
this time.
|
|
|
|
If unsure, say N.
|
|
|
|
config CIFS_POSIX
|
|
bool "CIFS POSIX Extensions"
|
|
depends on CIFS_XATTR
|
|
help
|
|
Enabling this option will cause the cifs client to attempt to
|
|
negotiate a newer dialect with servers, such as Samba 3.0.5
|
|
or later, that optionally can handle more POSIX like (rather
|
|
than Windows like) file behavior. It also enables
|
|
support for POSIX ACLs (getfacl and setfacl) to servers
|
|
(such as Samba 3.10 and later) which can negotiate
|
|
CIFS POSIX ACL support. If unsure, say N.
|
|
|
|
config CIFS_DEBUG2
|
|
bool "Enable additional CIFS debugging routines"
|
|
depends on CIFS
|
|
help
|
|
Enabling this option adds a few more debugging routines
|
|
to the cifs code which slightly increases the size of
|
|
the cifs module and can cause additional logging of debug
|
|
messages in some error paths, slowing performance. This
|
|
option can be turned off unless you are debugging
|
|
cifs problems. If unsure, say N.
|
|
|
|
config CIFS_DFS_UPCALL
|
|
bool "DFS feature support"
|
|
depends on CIFS && KEYS
|
|
select DNS_RESOLVER
|
|
help
|
|
Distributed File System (DFS) support is used to access shares
|
|
transparently in an enterprise name space, even if the share
|
|
moves to a different server. This feature also enables
|
|
an upcall mechanism for CIFS which contacts userspace helper
|
|
utilities to provide server name resolution (host names to
|
|
IP addresses) which is needed for implicit mounts of DFS junction
|
|
points. If unsure, say N.
|
|
|
|
config CIFS_FSCACHE
|
|
bool "Provide CIFS client caching support"
|
|
depends on CIFS=m && FSCACHE || CIFS=y && FSCACHE=y
|
|
help
|
|
Makes CIFS FS-Cache capable. Say Y here if you want your CIFS data
|
|
to be cached locally on disk through the general filesystem cache
|
|
manager. If unsure, say N.
|
|
|
|
config CIFS_ACL
|
|
bool "Provide CIFS ACL support"
|
|
depends on CIFS_XATTR && KEYS
|
|
help
|
|
Allows to fetch CIFS/NTFS ACL from the server. The DACL blob
|
|
is handed over to the application/caller.
|
|
|
|
config CIFS_NFSD_EXPORT
|
|
bool "Allow nfsd to export CIFS file system (EXPERIMENTAL)"
|
|
depends on CIFS && EXPERIMENTAL && BROKEN
|
|
help
|
|
Allows NFS server to export a CIFS mounted share (nfsd over cifs)
|
|
|
|
config CIFS_SMB2
|
|
bool "SMB2 network file system support (EXPERIMENTAL)"
|
|
depends on EXPERIMENTAL && INET && BROKEN
|
|
select NLS
|
|
select KEYS
|
|
select FSCACHE
|
|
select DNS_RESOLVER
|
|
|
|
help
|
|
This enables experimental support for the SMB2 (Server Message Block
|
|
version 2) protocol. The SMB2 protocol is the successor to the
|
|
popular CIFS and SMB network file sharing protocols. SMB2 is the
|
|
native file sharing mechanism for recent versions of Windows
|
|
operating systems (since Vista). SMB2 enablement will eventually
|
|
allow users better performance, security and features, than would be
|
|
possible with cifs. Note that smb2 mount options also are simpler
|
|
(compared to cifs) due to protocol improvements.
|
|
|
|
Unless you are a developer or tester, say N.
|