Copyright (c) 2000 Markus Friedl. All rights reserved.
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.Dd $Mdocdate: December 11 2014 $ .Dt SFTP-SERVER 8 .Os .Sh NAME .Nm sftp-server .Nd SFTP server subsystem .Sh SYNOPSIS .Nm sftp-server k -words .Op Fl ehR .Op Fl d Ar start_directory .Op Fl f Ar log_facility .Op Fl l Ar log_level .Op Fl P Ar blacklisted_requests .Op Fl p Ar whitelisted_requests .Op Fl u Ar umask .Ek .Nm .Fl Q Ar protocol_feature .Sh DESCRIPTION .Nm is a program that speaks the server side of SFTP protocol to stdout and expects client requests from stdin. .Nm is not intended to be called directly, but from .Xr sshd 8 using the .Cm Subsystem option.
p Command-line flags to .Nm should be specified in the .Cm Subsystem declaration. See .Xr sshd_config 5 for more information.
p Valid options are: l -tag -width Ds t Fl d Ar start_directory specifies an alternate starting directory for users. The pathname may contain the following tokens that are expanded at runtime: %% is replaced by a literal '%', %d is replaced by the home directory of the user being authenticated, and %u is replaced by the username of that user. The default is to use the user's home directory. This option is useful in conjunction with the .Xr sshd_config 5 .Cm ChrootDirectory option. t Fl e Causes .Nm to print logging information to stderr instead of syslog for debugging. t Fl f Ar log_facility Specifies the facility code that is used when logging messages from .Nm . The possible values are: DAEMON, USER, AUTH, LOCAL0, LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7. The default is AUTH. t Fl h Displays .Nm usage information. t Fl l Ar log_level Specifies which messages will be logged by .Nm . The possible values are: QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. INFO and VERBOSE log transactions that .Nm performs on behalf of the client. DEBUG and DEBUG1 are equivalent. DEBUG2 and DEBUG3 each specify higher levels of debugging output. The default is ERROR. t Fl P Ar blacklisted_requests Specify a comma-separated list of SFTP protocol requests that are banned by the server. .Nm will reply to any blacklisted request with a failure. The .Fl Q flag can be used to determine the supported request types. If both a blacklist and a whitelist are specified, then the blacklist is applied before the whitelist. t Fl p Ar whitelisted_requests Specify a comma-separated list of SFTP protocol requests that are permitted by the server. All request types that are not on the whitelist will be logged and replied to with a failure message.
p Care must be taken when using this feature to ensure that requests made implicitly by SFTP clients are permitted. t Fl Q Ar protocol_feature Query protocol features supported by .Nm . At present the only feature that may be queried is .Dq requests , which may be used for black or whitelisting (flags .Fl P and .Fl p respectively). t Fl R Places this instance of .Nm into a read-only mode. Attempts to open files for writing, as well as other operations that change the state of the filesystem, will be denied. t Fl u Ar umask Sets an explicit .Xr umask 2 to be applied to newly-created files and directories, instead of the user's default mask. .El
p On some systems, .Nm must be able to access
a /dev/log for logging to work, and use of .Nm in a chroot configuration therefore requires that .Xr syslogd 8 establish a logging socket inside the chroot directory. .Sh SEE ALSO .Xr sftp 1 , .Xr ssh 1 , .Xr sshd_config 5 , .Xr sshd 8 .Rs .%A T. Ylonen .%A S. Lehtinen .%T "SSH File Transfer Protocol" .%N draft-ietf-secsh-filexfer-02.txt .%D October 2001 .%O work in progress material .Re .Sh HISTORY .Nm first appeared in .Ox 2.8 . .Sh AUTHORS .An Markus Friedl Aq Mt markus (at] openbsd.org
