SFTP - using keys with 2048/4096 bits

Question

Hi,
I generated SSH2-RSA keypairs using PuttyGen and when connecting using Public Key authentication, I'm getting:
"SFTP error. Failed to recognize key format. Supported formats are OpenSSH, SSH.com and PuTTY" if the keys were generated with 2048 or 4096 bits.

It works fine with 1024 bit keys.

Are larger keys not supported?

Thanks

Answer 1

Please post the log file at Debug level - that should be ok.

Answer 2

2014-05-12 12:11:20,413 [11] [(null)] [(null)] [(null)] INFO EnterpriseDTLog - Negotiated new keys successfully
2014-05-12 12:11:20,414 [11] [(null)] [(null)] [(null)] DEBUG EnterpriseDTLog - Key exchange complete
2014-05-12 12:11:20,417 [11] [(null)] [(null)] [(null)] DEBUG EnterpriseDTLog - Sent SSH_MSG_SERVICE_REQUEST 'ssh-userauth'
2014-05-12 12:11:20,418 [11] [(null)] [(null)] [(null)] DEBUG EnterpriseDTLog - Starting user authentication
2014-05-12 12:11:20,419 [11] [(null)] [(null)] [(null)] DEBUG EnterpriseDTLog - Public key authentication
2014-05-12 12:11:20,420 [11] [(null)] [(null)] [(null)] ERROR EnterpriseDTLog - Failed to recognize key format. Supported formats are OpenSSH, SSH.com and PuTTY.
2014-05-12 12:11:20,990 [11] [(null)] [(null)] [(null)] ERROR EnterpriseDTLog - Failed to connect - closing connection
EnterpriseDT.Net.Ftp.Ssh.SFTPException: Failed to recognize key format. Supported formats are OpenSSH, SSH.com and PuTTY.
at jPYYciygkWVsNkdo8BJ.c7VwWAy6cbaTpQ2mfDT.e9fBjNrPsV(Byte[] )
at jPYYciygkWVsNkdo8BJ.c7VwWAy6cbaTpQ2mfDT.AyRB6wlLGg(Byte[] , String )
at z3SYecFHg77cP9L4NSc.QfdhGeF1v63VpDKrlwI.ywFJOsolRq(Byte[] , String )
at t5WiscyZg77KuQASFm5.A3bEFByvyVkt8WHM3R7.hkAIz06riG(AuthenticationType )
at t5WiscyZg77KuQASFm5.A3bEFByvyVkt8WHM3R7.Connect(oeiIiItSa3NDMsfDMI )
at e0jp1nF39MZSkUSywtR.s5n8E8FaCwJ18NQVWiJ.h6YPZW2Yyt(doqv7NXNQu01RXln4G8 , gJ1JLa24WQgZWoR7tU , wItEGos8h0rCvOyZB0 , oeiIiItSa3NDMsfDMI )
at e0jp1nF39MZSkUSywtR.s5n8E8FaCwJ18NQVWiJ.tHQPEyWorO(doqv7NXNQu01RXln4G8 , gJ1JLa24WQgZWoR7tU , Socket , ILogTag )
at EnterpriseDT.Net.Ftp.Ssh.SSHFTPClient.Connect()

Answer 3

Hi,
Apologies! Please ignore this query. The problem was on our side - Entity Framework was limiting our strings to 1024!