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Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

sftp-server.8 (5102B)


  1. .\" $OpenBSD: sftp-server.8,v 1.31 2021/07/27 14:14:25 jmc Exp $
  2. .\"
  3. .\" Copyright (c) 2000 Markus Friedl. All rights reserved.
  4. .\"
  5. .\" Redistribution and use in source and binary forms, with or without
  6. .\" modification, are permitted provided that the following conditions
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  8. .\" 1. Redistributions of source code must retain the above copyright
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  14. .\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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  25. .Dd $Mdocdate: July 27 2021 $
  26. .Dt SFTP-SERVER 8
  27. .Os
  28. .Sh NAME
  29. .Nm sftp-server
  30. .Nd OpenSSH SFTP server subsystem
  31. .Sh SYNOPSIS
  32. .Nm sftp-server
  33. .Bk -words
  34. .Op Fl ehR
  35. .Op Fl d Ar start_directory
  36. .Op Fl f Ar log_facility
  37. .Op Fl l Ar log_level
  38. .Op Fl P Ar denied_requests
  39. .Op Fl p Ar allowed_requests
  40. .Op Fl u Ar umask
  41. .Ek
  42. .Nm
  43. .Fl Q Ar protocol_feature
  44. .Sh DESCRIPTION
  45. .Nm
  46. is a program that speaks the server side of SFTP protocol
  47. to stdout and expects client requests from stdin.
  48. .Nm
  49. is not intended to be called directly, but from
  50. .Xr sshd 8
  51. using the
  52. .Cm Subsystem
  53. option.
  54. .Pp
  55. Command-line flags to
  56. .Nm
  57. should be specified in the
  58. .Cm Subsystem
  59. declaration.
  60. See
  61. .Xr sshd_config 5
  62. for more information.
  63. .Pp
  64. Valid options are:
  65. .Bl -tag -width Ds
  66. .It Fl d Ar start_directory
  67. Specifies an alternate starting directory for users.
  68. The pathname may contain the following tokens that are expanded at runtime:
  69. %% is replaced by a literal '%',
  70. %d is replaced by the home directory of the user being authenticated,
  71. and %u is replaced by the username of that user.
  72. The default is to use the user's home directory.
  73. This option is useful in conjunction with the
  74. .Xr sshd_config 5
  75. .Cm ChrootDirectory
  76. option.
  77. .It Fl e
  78. Causes
  79. .Nm
  80. to print logging information to stderr instead of syslog for debugging.
  81. .It Fl f Ar log_facility
  82. Specifies the facility code that is used when logging messages from
  83. .Nm .
  84. The possible values are: DAEMON, USER, AUTH, LOCAL0, LOCAL1, LOCAL2,
  85. LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7.
  86. The default is AUTH.
  87. .It Fl h
  88. Displays
  89. .Nm
  90. usage information.
  91. .It Fl l Ar log_level
  92. Specifies which messages will be logged by
  93. .Nm .
  94. The possible values are:
  95. QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.
  96. INFO and VERBOSE log transactions that
  97. .Nm
  98. performs on behalf of the client.
  99. DEBUG and DEBUG1 are equivalent.
  100. DEBUG2 and DEBUG3 each specify higher levels of debugging output.
  101. The default is ERROR.
  102. .It Fl P Ar denied_requests
  103. Specifies a comma-separated list of SFTP protocol requests that are banned by
  104. the server.
  105. .Nm
  106. will reply to any denied request with a failure.
  107. The
  108. .Fl Q
  109. flag can be used to determine the supported request types.
  110. If both denied and allowed lists are specified, then the denied list is
  111. applied before the allowed list.
  112. .It Fl p Ar allowed_requests
  113. Specifies a comma-separated list of SFTP protocol requests that are permitted
  114. by the server.
  115. All request types that are not on the allowed list will be logged and replied
  116. to with a failure message.
  117. .Pp
  118. Care must be taken when using this feature to ensure that requests made
  119. implicitly by SFTP clients are permitted.
  120. .It Fl Q Ar protocol_feature
  121. Queries protocol features supported by
  122. .Nm .
  123. At present the only feature that may be queried is
  124. .Dq requests ,
  125. which may be used to deny or allow specific requests (flags
  126. .Fl P
  127. and
  128. .Fl p
  129. respectively).
  130. .It Fl R
  131. Places this instance of
  132. .Nm
  133. into a read-only mode.
  134. Attempts to open files for writing, as well as other operations that change
  135. the state of the filesystem, will be denied.
  136. .It Fl u Ar umask
  137. Sets an explicit
  138. .Xr umask 2
  139. to be applied to newly-created files and directories, instead of the
  140. user's default mask.
  141. .El
  142. .Pp
  143. On some systems,
  144. .Nm
  145. must be able to access
  146. .Pa /dev/log
  147. for logging to work, and use of
  148. .Nm
  149. in a chroot configuration therefore requires that
  150. .Xr syslogd 8
  151. establish a logging socket inside the chroot directory.
  152. .Sh SEE ALSO
  153. .Xr sftp 1 ,
  154. .Xr ssh 1 ,
  155. .Xr sshd_config 5 ,
  156. .Xr sshd 8
  157. .Rs
  158. .%A T. Ylonen
  159. .%A S. Lehtinen
  160. .%T "SSH File Transfer Protocol"
  161. .%N draft-ietf-secsh-filexfer-02.txt
  162. .%D October 2001
  163. .%O work in progress material
  164. .Re
  165. .Sh HISTORY
  166. .Nm
  167. first appeared in
  168. .Ox 2.8 .
  169. .Sh AUTHORS
  170. .An Markus Friedl Aq Mt markus@openbsd.org