Acabei de gerar uma chave ECDSA com ssh-keygen
:
ssh-keygen -t ecdsa -b 521
Eu então copiei essa chave para o meu servidor:
cat .ssh/id_ecdsa.pub | ssh myserver "tee -a .ssh/authorized_keys"
Eu verifiquei que minha chave está no arquivo.
No entanto, quando tento me conectar, minha conexão é rejeitada:
ssh -v -i .ssh/id_ecdsa myserver
Logs:
OpenSSH_5.9p1 Debian-5ubuntu1.1, OpenSSL 1.0.1 14 Mar 2012
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 19: Applying options for *
debug1: Connecting to myserver [192.168.1.1] port 22.
debug1: Connection established.
debug1: identity file .ssh/id_ecdsa type 3
debug1: Checking blacklist file /usr/share/ssh/blacklist.ECDSA-521
debug1: Checking blacklist file /etc/ssh/blacklist.ECDSA-521
debug1: identity file .ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_6.1
debug1: match: OpenSSH_6.1 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9p1 Debian-5ubuntu1.1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST(1024<1024<8192) sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug1: Server host key: RSA 10:27:b8:78:2c:e1:e3:42:8e:e3:66:c4:cc:4e:f1:c0
debug1: Host 'myserver' is known and matches the RSA host key.
debug1: Found key in /home/naftuli/.ssh/known_hosts:73
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug1: Authentications that can continue: publickey
debug1: Next authentication method: publickey
debug1: Offering ECDSA public key: .ssh/id_ecdsa
debug1: Authentications that can continue: publickey
debug1: No more authentication methods to try.
Permission denied (publickey).
Encontrei isso nos registros do servidor:
auth.info sshd[13874]: userauth_pubkey: unsupported public key algorithm: ecdsa-sha2-nistp521 [preauth]
Meu cliente e o servidor estão usando o OpenSSH. A versão do OpenSSH do servidor é OpenSSH 6.1, a versão do OpenSSH do meu cliente é o OpenSSH 5.9.
Como posso saber quais algoritmos de chave são suportados pelo meu servidor?