SFTP-SERVER(8)SFTP-SERVER(8)NAMEsftp-server - SFTP server subsystem
SYNOPSISsftp-server [-ehR] [-d start_directory] [-f log_facility] [-l
log_level] [-P blacklisted_requests] [-p whitelisted_requests] [-u
umask]
sftp-server-Q protocol_feature
DESCRIPTIONsftp-server is a program that speaks the server side of SFTP protocol
to stdout and expects client requests from stdin. sftp-server is not
intended to be called directly, but from sshd(8) using the Subsystem
option.
Command-line flags to sftp-server should be specified in the Subsystem
declaration. See sshd_config(5) for more information.
Valid options are:
-d start_directory
specifies an alternate starting directory for users. The path‐
name may contain the following tokens that are expanded at run‐
time: %% is replaced by a literal '%', %h 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 sshd_config(5) ChrootDirectory option.
-e Causes sftp-server to print logging information to stderr
instead of syslog for debugging.
-f log_facility
Specifies the facility code that is used when logging messages
from . The possible values are: DAEMON, USER, AUTH, LOCAL0,
LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7. The
default is AUTH.
-h Displays sftp-server usage information.
-l log_level
Specifies which messages will be logged by . The possible val‐
ues are: QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1,
DEBUG2, and DEBUG3. INFO and VERBOSE log transactions that
sftp-server 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.
-P blacklisted_requests
Specify a comma-separated list of SFTP protocol requests that
are banned by the server. sftp-server will reply to any black‐
listed request with a failure. The -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.
-p 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 mes‐
sage.
Care must be taken when using this feature to ensure that
requests made implicitly by SFTP clients are permitted.
-Q protocol_feature
Query protocol features supported by . At present the only fea‐
ture that may be queried is ``requests'', which may be used for
black or whitelisting (flags -P and -p respectively).
-R Places this instance of sftp-server 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.
-u umask
Sets an explicit umask(2) to be applied to newly-created files
and directories, instead of the user's default mask.
For logging to work, sftp-server must be able to access
/dev/log. Use of sftp-server in a chroot configuration there‐
fore requires that syslogd(8) establish a logging socket inside
the chroot directory.
SEE ALSOsftp(1), ssh(1), sshd_config(5), sshd(8)
S. Lehtinen and T. Ylonen, SSH File Transfer Protocol, draft-ietf-
secsh-filexfer-02.txt, October 2001, work in progress material.
HISTORYsftp-server first appeared in OpenBSD 2.8 .
AUTHORS
Markus Friedl <Mt markus@openbsd.org>
October 14 2013 SFTP-SERVER(8)
