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Skarafaz / mercury

Simple Android app that sends pre-configured commands to remote servers via SSH.
GNU General Public License v2.0
115 stars 20 forks source link

error: algorithm negotiation fail #5

Closed axelsimon closed 5 years ago

axelsimon commented 9 years ago

Hi,

I use a somewhat hardened sshd config, in which I have the following: Ciphers aes256-ctr MACs hmac-sha2-512, hmac-sha2-256 KexAlgorithms diffie-hellman-group-exchange-sha256

This apparently prevents MercurySSH from connecting, I find a "ERROR: algorithm negotiation fail" in the logs.

I haven't digged in the code, but I think we should encourage strong crypto for SSH (in general), so it might be a good idea to make sure strong ciphers etc. don't break Mercury.

Thanks for a cool app otherwise!

Cheers

Skarafaz commented 9 years ago

Hi! You are right, at the moment mercury does not support advanced encryption/compression settings. I'll take a look! Thank you for pointing that out.

axelsimon commented 9 years ago

Just figured my sshd_conf had an issue. hmac-sha2-512, hmac-sha2-256 should be hmac-sha2-512,hmac-sha2-256.

I've corrected it, but the same error appears in the logs.

Thanks for your answer in any case Skarafaz :)

DocSniper commented 7 years ago

For a really secure and up-to-date sshd setup the following algorithms should be included:

KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256

Ciphers chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr

MACs hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com

And thank you for this useful app. :-)

axelsimon commented 7 years ago

Any news on this? Even just “not happening anytime soon”. Sorry to bump up a bug report, but this bug report was opened nearly 18 months ago :wink:

Skarafaz commented 7 years ago

I'm sorry but I have to confirm the “not happening anytime soon”. Stay tuned!

Skarafaz commented 5 years ago

Updating jsch to the last version fixed the original problem.