FS Does not support secure directory streams & NOFOLLOW_LINKS on IBM i #742
Description
Version
2.12.1
Bug description
The new WinSCP client version 6.5 sends the FileAttribute "size" when opening a file. This leads to following Exception:
java.lang.UnsupportedOperationException: FS Does not support secure directory streams.
at org.apache.sshd.sftp.server.SftpFileSystemAccessor.secure(SftpFileSystemAccessor.java:593)
at org.apache.sshd.sftp.server.SftpFileSystemAccessor.secureResolveDirectoryStream(SftpFileSystemAccessor.java:585)
at org.apache.sshd.sftp.server.SftpFileSystemAccessor.seekableByteChannelNoLinkFollow(SftpFileSystemAccessor.java:565)
at org.apache.sshd.sftp.server.SftpFileSystemAccessor.openFile(SftpFileSystemAccessor.java:217)
at org.apache.sshd.sftp.server.AbstractSftpSubsystemHelper.setFileAttributes(AbstractSftpSubsystemHelper.java:2707)
at org.apache.sshd.sftp.server.AbstractSftpSubsystemHelper.doSetAttributes(AbstractSftpSubsystemHelper.java:2671)
at org.apache.sshd.sftp.server.FileHandle.<init>(FileHandle.java:94)
at org.apache.sshd.sftp.server.SftpSubsystem.doOpen(SftpSubsystem.java:968)
at org.apache.sshd.sftp.server.AbstractSftpSubsystemHelper.doOpen(AbstractSftpSubsystemHelper.java:496)
at org.apache.sshd.sftp.server.AbstractSftpSubsystemHelper.doProcess(AbstractSftpSubsystemHelper.java:353)
at org.apache.sshd.sftp.server.SftpSubsystem.doProcess(SftpSubsystem.java:355)
at org.apache.sshd.sftp.server.AbstractSftpSubsystemHelper.process(AbstractSftpSubsystemHelper.java:344)
at org.apache.sshd.sftp.server.SftpSubsystem.run(SftpSubsystem.java:331)
I identified the problem in org.apache.sshd.sftp.server.FileHandle.java
SftpFileSystemAccessor accessor = subsystem.getFileSystemAccessor();
SeekableByteChannel channel;
try {
channel = accessor.openFile(
subsystem, this, file, handle, openOptions, fileAttrs);
} catch (UnsupportedOperationException e) {
channel = accessor.openFile(
subsystem, this, file, handle, openOptions, IoUtils.EMPTY_FILE_ATTRIBUTES);
subsystem.doSetAttributes(SftpConstants.SSH_FXP_OPEN, "", file, attrs, false);
}
Actual behavior
- The first accessor.openFile(...) throws an exception that is not shown in log
- Second accessor.openFile(...) creates file, but subsystem.doSetAttributes(...) throws Exception "FS Does not support secure directory streams", because followLinks is hard-coded to false and not supported on IBM i.
Expected behavior
- Show the exception on debug/trace log
- Do not use followLinks=false if it can lead to problems. A fallback as it is mentioned before the exception. Or maybe some way to configure it?
Relevant log output
Other information
No response