shithub: riscv

ref: a3beef236344ca326ed2010580b99e50cab983da
dir: /sys/man/4/cifs/

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.TH CIFS 4
.SH NAME
cifs - Microsoft™ Windows network filesystem client
.SH SYNOPSIS
.B cifs
[
.B -bDiv
] [
.B -d
.I debug
] [
.B -a
.I auth-method
] [
.B -s
.I srvname
] [
.B -n
.I called-name
] [
.B -k
.I keyparam
] [
.B -m
.I mntpnt
] [
.B -t
.I dfs-timeout
]
.I host
[
.I share ...
]
.SH DESCRIPTION
.I Cifs
translates between Microsoft's file-sharing protocol
(a.k.a. CIFS or SMB) and 9P, allowing Plan9 clients to mount file systems
(shares or trees in MS terminology) published by such servers.
.PP
The root of the mounted directory contains one subdirectory per share,
and a few virtual files give additional information.
The arguments are:
.TF "-a\fI auth-method"
.PD
.TP
.BI -a " auth-method"
.I Cifs
authenticates using
.B ntlmv2
by default, but alternative strategies may be
selected using this option.
.I Cifs
eschews cleartext authentication, however
it may be enabled with the
.L plain
auth method.
The list of currently-supported methods is printed
if no method name is supplied.
.IP
.I "Windows server 2003"
requires the
.B ntlmv2
method by default, though it can be configured to be more flexible.
.TP
.B -b
Enable file ownership resolution in
.IR stat (2)
calls.
This requires an open and close per file and thus will slow
.I cifs
considerably; its use is not recommended.
.TP
.BI -d " debug"
followed by non-whitespace separated list of debug options
.I debug
writes specific debug output to file descriptor 2. See source
for more information.
.TP
.B -D
9P request debug.
.TP
.B -i 
By default 
.I cifs
attempts to enforce case significance file and directory names, though objects
which differ only in their case still cannot co-exist in the same directory. The
.B -i
option disables this behaveiour.
.TP
.BI -k " keyparam"
lists extra parameters which will be passed to
.IR factotum (4)
to select a specific key.
The remote servers's domain is always included in the keyspec,
under the assumption
that all servers in a Windows domain share an authentication domain;
thus
.I cifs
expects keys in
.I factotum
of the form:
.RS
.IP
.EX
key proto=pass dom=THEIR-DOMAIN service=cifs
	user=MY-USERNAME !password=XYZZY
.EE
.RE
.TP
.BI -m " mntpnt"
set the mount point for the remote filesystem;
the default is
.BI /n/ host.
.TP
.BI -n " called-name"
The CIFS protocol requires clients to know the NetBios name of the
server they are attaching to, the
.IR Icalled-name .
If this is not specified on the command line,
.I cifs
attempts to discover this name from the remote server.
If this fails it will then try
.IR host ,
and finally it will try the name
.LR *SMBSERVER .
.TP
.BI -s " srvname"
post the service as
.BI /srv/ srvname.
.TP
.BI -t " dfs-timeout"
sets the timeout in for DFS redirections - it defaults to 100ms.
This is a reasonable minimum, it should have a value just greater than
the RTT to the most distant server being accessed.
.TP
.I host
The address of the remote server to connect to.
.TP
.I share
A list of share names to attach on the remote server; if none is given,
.I cifs
will attempt to attach all shares published by the remote host.
.SS "Synthetic Files"
Several synthetic files appear in the root of the mounted filesystem:
.TF Workstations
.PD
.TP
.B Shares
Contains a list of the currently attached shares,
with fields giving the share name, the share type, disk free space / capacity, 
and a descriptive comment from the server.
.TP
.B Connection
Contains the username used for authentication,
server's called name, server's domain,
server's OS, the time slip between the local host and the server,
the Maximum Transfer Unit (MTU) the server requested, and optionally a flag
indicating only guest access has been granted.
The second line contains a list of capabilities offered by the server which is
mainly of use for debugging
.IR cifs .
.TP
.B Users
Each line contains a user's name, the user's full name,
and a descriptive comment.
.TP
.B Groups
Each line gives a group's name, and a list of the names of the users who
are members of that group.
.TP
.B Sessions
Lists the users authenticated, the client machine's NetBios name or IP address,
the time since the connection was established,
and the time for which the connection has been idle.
.TP
.B Domains
One line per domain giving the domain name and a descriptive comment.
.TP
.B Workstations
One line per domain giving the domain name and a descriptive comment,
the version number of the OS it is running, and comma-separated list of flags
giving the features of that OS.
.TP
.B Dfsroot
Lists the top level DFS domains and the servers that
provision them.
.TP
.B Dfscache
Contents of the DFS referal cache, giving the path prefix,
the expiry time (or -1 for never), the measured RTT to the server
in milliseconds, the server proximity (0 is local), the server name,
and the share name on that server.
.SH COMPATIBILITY
.I Cifs
has been tested against aquarela,
.IR cifsd (8),
Windows 95, NT4.0sp6,
Windows server 2003, Windows server 2003, WinXP pro, 
Samba 2.0 (Pluto VideoSpace), and Samba 3.0.
.LP
Windows Vista require a hotfix (registry change)
to support NTLMv2 without GSSAPI, see http://support.microsoft.com/kb/957441.
Alternatively the
.B -a
option can be used to force
.I cifs
to use one of the less secure authentication mechnisms.
.LP
Windows 7 has dropped support for RAP, which is used to generate
the synthetic files offered by
.IR cifs .
RAP is also used to enumerate the shares offered by the remote host so
remote share names must always be specified on the command line.
.LP
The NetApp Filer was supported by earlier releases, however recent
attempts to mount one have failed. Should a server be available it is
likely that this could be easily fixed.
.PP
.SH SOURCE
.B /sys/src/cmd/cifs
.SH SEE ALSO
.IR factotum (4),
.IR cifsd (8)
.SH BUGS
DFS support is unfinished, it will not follow referals that span servers.
.PP
Kerberos authentication is not supported.
.PP
NetBios name resolution is not supported, though it is now rarely used.
.SH HISTORY
.I Cifs
first appeared in Plan 9 from Bell Labs. It was updated to the author's
latest revision for 9front (January, 2012).