SOLVED SSH Key Authentication Problems

[Quinniedid]

So far I have created a user Dave. Gave Dave a storage with permission only to him. Also under his user profile same thing made sure permissions were only him for home directory. Passed a public-key that looks like this:

ssh-rsa
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
xGZiyMc=
Dave@freenas.local

Used PuTTY, choose the private key for authentication in options. Started login and ask for username. Entered username and then it gives me this:

No supported authentication methods available [preauth]

I have gone through other forums and still can't get this to work for the life of me. Any help would be much appreciated!!! Thank You!

Note: key is generated in 4096 bits if that is helpful at all

 

[ljw1]

You will need to check the ssh server config and ensure that the user is able to login as well as login with keys.

 

[Quinniedid]

I can connect to the freenas device with the username and password but not with the key. The user is part of the sftp group that I created.

 

[Quinniedid]

During more investigating to this problem I think it is not even sending the public key that I put into the user account. I have a 4096 bit key and the one that it is sending is a 2048 bit key? Any reason why it would not be sending the key that I entered into the user?

 

[Quinniedid]

I have figured it out a key that large is not supported as it overfills the buffer on Freenas. Went to a 2048 bit key and everything is working how it is suppose to. Thank you for your help!

Oct 13 12:02:06 freenas sshd[46522]: error: buffer_get_ret: trying to get more bytes 513 than in buffer 508
Oct 13 12:02:06 freenas sshd[46522]: error: buffer_get_string_ret: buffer_get failed
Oct 13 12:02:06 freenas sshd[46522]: error: buffer_get_bignum2_ret: invalid bignum
Oct 13 12:02:06 freenas sshd[46522]: error: key_from_blob: can't read rsa key

 

[dlavigne]

Regarding that point, please create a bug report at bugs.freenas.org and post the issue number here.

 

[Quinniedid]

Bug #6341: SSH Key Length

• Author: Quinn Johnson
• Status: Unscreened
• Priority: High
• Assignee:
• Category:
• Target version:
• Seen in: 9.2.1.8-RELEASE

When using a SSH RSA key with 4096 bits length, you get the following error

Oct 13 12:02:06 freenas sshd46522: error: buffer_get_ret: trying to get more bytes 513 than in buffer 508
Oct 13 12:02:06 freenas sshd46522: error: buffer_get_string_ret: buffer_get failed
Oct 13 12:02:06 freenas sshd46522: error: buffer_get_bignum2_ret: invalid bignum
Oct 13 12:02:06 freenas sshd46522: error: key_from_blob: can't read rsa key>

 

[Quinniedid]

Okay for some reason this size of key is now accepting. I think there might have been a space some where there shouldn't be. Thanks for all your help. Now running on a SSH-RSA 4096-bit key!