fs/cifs/Kconfig

   1 config CIFS
   2         tristate "SMB3 and CIFS support (advanced network filesystem)"
   3         depends on INET
   4         select NLS
   5         select CRYPTO
   6         select CRYPTO_MD4
   7         select CRYPTO_MD5
   8         select CRYPTO_HMAC
   9         select CRYPTO_ARC4
  10         select CRYPTO_ECB
  11         select CRYPTO_DES
  12         help
  13           This is the client VFS module for the SMB3 family of NAS protocols,
  14           as well as for earlier dialects such as SMB2.1, SMB2 and the
  15           Common Internet File System (CIFS) protocol.  CIFS was the successor
  16           to the original dialect, the Server Message Block (SMB) protocol, the
  17           native file sharing mechanism for most early PC operating systems.
  18
  19           The SMB3 protocol is supported by most modern operating systems and
  20           NAS appliances (e.g. Samba, Windows 8, Windows 2012, MacOS).
  21           The older CIFS protocol was included in Windows NT4, 2000 and XP (and
  22           later) as well by Samba (which provides excellent CIFS and SMB3
  23           server support for Linux and many other operating systems). Limited
  24           support for OS/2 and Windows ME and similar very old servers is
  25           provided as well.
  26
  27           The cifs module provides an advanced network file system client
  28           for mounting to SMB3 (and CIFS) compliant servers.  It includes
  29           support for DFS (hierarchical name space), secure per-user
  30           session establishment via Kerberos or NTLM or NTLMv2,
  31           safe distributed caching (oplock), optional packet
  32           signing, Unicode and other internationalization improvements.
  33
  34           In general, the default dialects, SMB3 and later, enable better
  35           performance, security and features, than would be possible with CIFS.
  36           Note that when mounting to Samba, due to the CIFS POSIX extensions,
  37           CIFS mounts can provide slightly better POSIX compatibility
  38           than SMB3 mounts. SMB2/SMB3 mount options are also
  39           slightly simpler (compared to CIFS) due to protocol improvements.
  40
  41           If you need to mount to Samba, Macs or Windows from this machine, say Y.
  42
  43 config CIFS_STATS
  44         bool "CIFS statistics"
  45         depends on CIFS
  46         help
  47           Enabling this option will cause statistics for each server share
  48           mounted by the cifs client to be displayed in /proc/fs/cifs/Stats
  49
  50 config CIFS_STATS2
  51         bool "Extended statistics"
  52         depends on CIFS_STATS
  53         help
  54           Enabling this option will allow more detailed statistics on SMB
  55           request timing to be displayed in /proc/fs/cifs/DebugData and also
  56           allow optional logging of slow responses to dmesg (depending on the
  57           value of /proc/fs/cifs/cifsFYI, see fs/cifs/README for more details).
  58           These additional statistics may have a minor effect on performance
  59           and memory utilization.
  60
  61           Unless you are a developer or are doing network performance analysis
  62           or tuning, say N.
  63
  64 config CIFS_WEAK_PW_HASH
  65         bool "Support legacy servers which use weaker LANMAN security"
  66         depends on CIFS
  67         help
  68           Modern CIFS servers including Samba and most Windows versions
  69           (since 1997) support stronger NTLM (and even NTLMv2 and Kerberos)
  70           security mechanisms. These hash the password more securely
  71           than the mechanisms used in the older LANMAN version of the
  72           SMB protocol but LANMAN based authentication is needed to
  73           establish sessions with some old SMB servers.
  74
  75           Enabling this option allows the cifs module to mount to older
  76           LANMAN based servers such as OS/2 and Windows 95, but such
  77           mounts may be less secure than mounts using NTLM or more recent
  78           security mechanisms if you are on a public network.  Unless you
  79           have a need to access old SMB servers (and are on a private
  80           network) you probably want to say N.  Even if this support
  81           is enabled in the kernel build, LANMAN authentication will not be
  82           used automatically. At runtime LANMAN mounts are disabled but
  83           can be set to required (or optional) either in
  84           /proc/fs/cifs (see fs/cifs/README for more detail) or via an
  85           option on the mount command. This support is disabled by
  86           default in order to reduce the possibility of a downgrade
  87           attack.
  88
  89           If unsure, say N.
  90
  91 config CIFS_UPCALL
  92         bool "Kerberos/SPNEGO advanced session setup"
  93         depends on CIFS && KEYS
  94         select DNS_RESOLVER
  95         help
  96           Enables an upcall mechanism for CIFS which accesses userspace helper
  97           utilities to provide SPNEGO packaged (RFC 4178) Kerberos tickets
  98           which are needed to mount to certain secure servers (for which more
  99           secure Kerberos authentication is required). If unsure, say Y.
 100
 101 config CIFS_XATTR
 102         bool "CIFS extended attributes"
 103         depends on CIFS
 104         help
 105           Extended attributes are name:value pairs associated with inodes by
 106           the kernel or by users (see the attr(5) manual page, or visit
 107           <http://acl.bestbits.at/> for details).  CIFS maps the name of
 108           extended attributes beginning with the user namespace prefix
 109           to SMB/CIFS EAs. EAs are stored on Windows servers without the
 110           user namespace prefix, but their names are seen by Linux cifs clients
 111           prefaced by the user namespace prefix. The system namespace
 112           (used by some filesystems to store ACLs) is not supported at
 113           this time.
 114
 115           If unsure, say Y.
 116
 117 config CIFS_POSIX
 118         bool "CIFS POSIX Extensions"
 119         depends on CIFS_XATTR
 120         help
 121           Enabling this option will cause the cifs client to attempt to
 122           negotiate a newer dialect with servers, such as Samba 3.0.5
 123           or later, that optionally can handle more POSIX like (rather
 124           than Windows like) file behavior.  It also enables
 125           support for POSIX ACLs (getfacl and setfacl) to servers
 126           (such as Samba 3.10 and later) which can negotiate
 127           CIFS POSIX ACL support.  If unsure, say N.
 128
 129 config CIFS_ACL
 130           bool "Provide CIFS ACL support"
 131           depends on CIFS_XATTR && KEYS
 132           help
 133             Allows fetching CIFS/NTFS ACL from the server.  The DACL blob
 134             is handed over to the application/caller.  See the man
 135             page for getcifsacl for more information.  If unsure, say Y.
 136
 137 config CIFS_DEBUG
 138         bool "Enable CIFS debugging routines"
 139         default y
 140         depends on CIFS
 141         help
 142            Enabling this option adds helpful debugging messages to
 143            the cifs code which increases the size of the cifs module.
 144            If unsure, say Y.
 145 config CIFS_DEBUG2
 146         bool "Enable additional CIFS debugging routines"
 147         depends on CIFS_DEBUG
 148         help
 149            Enabling this option adds a few more debugging routines
 150            to the cifs code which slightly increases the size of
 151            the cifs module and can cause additional logging of debug
 152            messages in some error paths, slowing performance. This
 153            option can be turned off unless you are debugging
 154            cifs problems.  If unsure, say N.
 155
 156 config CIFS_DEBUG_DUMP_KEYS
 157         bool "Dump encryption keys for offline decryption (Unsafe)"
 158         depends on CIFS_DEBUG
 159         help
 160            Enabling this will dump the encryption and decryption keys
 161            used to communicate on an encrypted share connection on the
 162            console. This allows Wireshark to decrypt and dissect
 163            encrypted network captures. Enable this carefully.
 164            If unsure, say N.
 165
 166 config CIFS_DFS_UPCALL
 167           bool "DFS feature support"
 168           depends on CIFS && KEYS
 169           select DNS_RESOLVER
 170           help
 171             Distributed File System (DFS) support is used to access shares
 172             transparently in an enterprise name space, even if the share
 173             moves to a different server.  This feature also enables
 174             an upcall mechanism for CIFS which contacts userspace helper
 175             utilities to provide server name resolution (host names to
 176             IP addresses) which is needed for implicit mounts of DFS junction
 177             points. If unsure, say Y.
 178
 179 config CIFS_NFSD_EXPORT
 180           bool "Allow nfsd to export CIFS file system"
 181           depends on CIFS && BROKEN
 182           help
 183            Allows NFS server to export a CIFS mounted share (nfsd over cifs)
 184
 185 config CIFS_SMB311
 186         bool "SMB3.1.1 network file system support (Experimental)"
 187         depends on CIFS
 188
 189         help
 190           This enables experimental support for the newest, SMB3.1.1, dialect.
 191           This dialect includes improved security negotiation features.
 192           If unsure, say N
 193
 194 config CIFS_FSCACHE
 195           bool "Provide CIFS client caching support"
 196           depends on CIFS=m && FSCACHE || CIFS=y && FSCACHE=y
 197           help
 198             Makes CIFS FS-Cache capable. Say Y here if you want your CIFS data
 199             to be cached locally on disk through the general filesystem cache
 200             manager. If unsure, say N.
 201