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RebexSFTP - can we control ciphers

0 votes
by (120 points)

I use the SFTP libraries to send secured data to a partner company. They told me yesterday that they are removing a few strong ciphers from their secure FTP site. I don't have any idea what ciphers are used in the Rebex libraries. Is this something I can control?

Applies to: Rebex SFTP

1 Answer

0 votes
by (144k points)

Yes, you can enable/disable SSH ciphers as needed using methods of Sftp object's Settings.SshParameters property.

Please see http://www.rebex.net/sftp.net/features/ssh.aspx#ciphers for details and list of supported ciphers.

by (120 points)
Are there any code examples for using the sshparameters property?
by (144k points)
There is a bit of sample code at http://www.rebex.net/sftp.net/features/connecting.aspx#connect-options

If you need any additional information, let us know.
by (120 points)
Since I need to explicitly disallow only a few AES ciphers, not the whole category, I tried this which seems to explicitly let me set a specific cipher ID...appeared to work.  Let me know if I did this correctly please:

sftp.Settings.SshParameters.SetEncryptionAlgorithms(new string[]{"aes256-ctr"});
by (144k points)
Yes, this enables "aes256-ctr" and disable all other ciphers (unless AES was disabled using SshParameters.EncryptionAlgorithms or CTR was disabled using SshParameters.EncryptionModes - in that case, the SSH client would fail due to an empty effective list of enabled ciphers).
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