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Diff for /src/usr.bin/ssh/PROTOCOL between version 1.5 and 1.6

version 1.5, 2008/06/09 13:38:46 version 1.6, 2008/06/10 22:15:23
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 still be sent in the other direction. This message does not consume  still be sent in the other direction. This message does not consume
 window space and may be sent even if no window space is available.  window space and may be sent even if no window space is available.
   
 4. sftp: Reversal of arguments to SSH_FXP_SYMLINK  4. connection: disallow additional sessions extension
      "no-more-sessions@openssh.com"
   
   Most SSH connections will only ever request a single session, but a
   attacker may abuse a running ssh client to surreptitiously open
   additional sessions under their control. OpenSSH provides a global
   request "no-more-sessions@openssh.com" to mitigate this attack.
   
   When an OpenSSH client expects that it will never open another session
   (i.e. it has been started with connection multiplexing disabled), it
   will send the following global request:
   
           byte            SSH_MSG_GLOBAL_REQUEST
           string          "no-more-sessions@openssh.com"
           char            want-reply
   
   On receipt of such a message, an OpenSSH server will refuse to open
   future channels of type "session" and instead immediately abort the
   connection.
   
   Note that this is not a general defence against compromised clients
   (that is impossible), but it thwarts a simple attack.
   
   5. sftp: Reversal of arguments to SSH_FXP_SYMLINK
   
 When OpenSSH's sftp-server was implemented, the order of the arguments  When OpenSSH's sftp-server was implemented, the order of the arguments
 to the SSH_FXP_SYMLINK method was inadvertendly reversed. Unfortunately,  to the SSH_FXP_SYMLINK method was inadvertendly reversed. Unfortunately,
 the reversal was not noticed until the server was widely deployed. Since  the reversal was not noticed until the server was widely deployed. Since
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         string          targetpath          string          targetpath
         string          linkpath          string          linkpath
   
 5. sftp: Server extension announcement in SSH_FXP_VERSION  6. sftp: Server extension announcement in SSH_FXP_VERSION
   
 OpenSSH's sftp-server lists the extensions it supports using the  OpenSSH's sftp-server lists the extensions it supports using the
 standard extension announcement mechanism in the SSH_FXP_VERSION server  standard extension announcement mechanism in the SSH_FXP_VERSION server
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 extension with multiple versions (though this is unlikely). Clients MUST  extension with multiple versions (though this is unlikely). Clients MUST
 check the version number before attemping to use the extension.  check the version number before attemping to use the extension.
   
 6. sftp: Extension request "posix-rename@openssh.com"  7. sftp: Extension request "posix-rename@openssh.com"
   
 This operation provides a rename operation with POSIX semantics, which  This operation provides a rename operation with POSIX semantics, which
 are different to those provided by the standard SSH_FXP_RENAME in  are different to those provided by the standard SSH_FXP_RENAME in
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 This extension is advertised in the SSH_FXP_VERSION hello with version  This extension is advertised in the SSH_FXP_VERSION hello with version
 "1".  "1".
   
 7. sftp: Extension requests "statvfs@openssh.com" and  8. sftp: Extension requests "statvfs@openssh.com" and
          "fstatvfs@openssh.com"           "fstatvfs@openssh.com"
   
 These requests correspond to the statvfs and fstatvfs POSIX system  These requests correspond to the statvfs and fstatvfs POSIX system
Legend:
Removed from v.1.5  
changed lines
  Added in v.1.6