1 files changed, 32 insertions, 7 deletions

diff --git a/fs/cifs/README b/fs/cifs/README
index 0355003f4f0a..7986d0d97ace 100644
--- a/fs/cifs/README
+++ b/fs/cifs/README
@@ -443,7 +443,10 @@ A partial list of the supported mount options follows:
                 SFU does).  In the future the bottom 9 bits of the mode
                 mode also will be emulated using queries of the security
                 descriptor (ACL).
-sec             Security mode.  Allowed values are:
+ sign           Must use packet signing (helps avoid unwanted data modification
+                by intermediate systems in the route).  Note that signing
+                does not work with lanman or plaintext authentication.
+ sec            Security mode.  Allowed values are:
                         none    attempt to connection as a null user (no name)
                         krb5    Use Kerberos version 5 authentication
                         krb5i   Use Kerberos authentication and packet signing
@@ -453,6 +456,8 @@ sec		Security mode.  Allowed values are:
                                 server requires signing also can be the default) 
                         ntlmv2  Use NTLMv2 password hashing      
                         ntlmv2i Use NTLMv2 password hashing with packet signing
+                        lanman  (if configured in kernel config) use older
+                                lanman hash
 
 The mount.cifs mount helper also accepts a few mount options before -o
 including:
@@ -485,14 +490,34 @@ PacketSigningEnabled	If set to one, cifs packet signing is enabled
                         it.  If set to two, cifs packet signing is
                         required even if the server considers packet
                         signing optional. (default 1)
+SecurityFlags           Flags which control security negotiation and
+                        also packet signing. Authentication (may/must)
+                        flags (e.g. for NTLM and/or NTLMv2) may be combined with
+                        the signing flags.  Specifying two different password
+                        hashing mechanisms (as "must use") on the other hand 
+                        does not make much sense. Default flags are 
+                                0x07007 
+                        (NTLM, NTLMv2 and packet signing allowed).  Maximum 
+                        allowable flags if you want to allow mounts to servers
+                        using weaker password hashes is 0x37037 (lanman,
+                        plaintext, ntlm, ntlmv2, signing allowed):
+ 
+                        may use packet signing                          0x00001
+                        must use packet signing                         0x01001
+                        may use NTLM (most common password hash)        0x00002
+                        must use NTLM                                   0x02002
+                        may use NTLMv2                                  0x00004
+                        must use NTLMv2                                 0x04004
+                        may use Kerberos security (not implemented yet) 0x00008
+                        must use Kerberos (not implemented yet)         0x08008
+                        may use lanman (weak) password hash             0x00010
+                        must use lanman password hash                   0x10010
+                        may use plaintext passwords                     0x00020
+                        must use plaintext passwords                    0x20020
+                        (reserved for future packet encryption)         0x00040
+
 cifsFYI                 If set to one, additional debug information is
                         logged to the system error log. (default 0)
-ExtendedSecurity        If set to one, SPNEGO session establishment
-                        is allowed which enables more advanced 
-                        secure CIFS session establishment (default 0)
-NTLMV2Enabled           If set to one, more secure password hashes
-                        are used when the server supports them and
-                        when kerberos is not negotiated (default 0)
 traceSMB                If set to one, debug information is logged to the
                         system error log with the start of smb requests
                         and responses (default 0)