SSH as root using public key still prompts for password on RHEL 6.1
- by Dean Schulze
I've generated rsa keys with cygwin ssh-keygen and copied them to the server with
ssh-copy-id -i id_rsa.pub [email protected]
I've got the following settings in my /etc/ssh/sshd_config file
RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile .ssh/authorized_keys
PermitRootLogin yes
When I ssh [email protected] it still prompts for a password.
The output below from /usr/sbin/sshd -d says that a matching keys was found in the .ssh/authorized_keys file, but it still requires a password from the client.
I've read a bunch of web postings about permissions on files and directories, but nothing works. Is it possible to ssh with keys in RHEL 6.1 or is this forbidden?
The debug output from ssh and sshd is below.
$ ssh -v [email protected]
OpenSSH_6.1p1, OpenSSL 1.0.1c 10 May 2012
debug1: Connecting to my.ip.address [my.ip.address] port 22.
debug1: Connection established.
debug1: identity file /home/dschulze/.ssh/id_rsa type 1
debug1: identity file /home/dschulze/.ssh/id_rsa-cert type -1
debug1: identity file /home/dschulze/.ssh/id_dsa type 2
debug1: identity file /home/dschulze/.ssh/id_dsa-cert type -1
debug1: identity file /home/dschulze/.ssh/id_ecdsa type -1
debug1: identity file /home/dschulze/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.3
debug1: match: OpenSSH_5.3 pat OpenSSH_5*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_6.1
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 9f:00:e0:1e:a2:cd:05:53:c8:21:d5:69:25:80:39:92
debug1: Host 'my.ip.address' is known and matches the RSA host key.
debug1: Found key in /home/dschulze/.ssh/known_hosts:3
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,gssapi-keyex,gssapi-with-mic,password
debug1: Next authentication method: publickey
debug1: Offering RSA public key: /home/dschulze/.ssh/id_rsa
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug1: Offering DSA public key: /home/dschulze/.ssh/id_dsa
debug1: Authentications that can continue: publickey,gssapi-keyex,gssapi-with-mic,password
debug1: Trying private key: /home/dschulze/.ssh/id_ecdsa
debug1: Next authentication method: password
Here is the server output from /usr/sbin/sshd -d
[root@ga2-lab .ssh]# /usr/sbin/sshd -d
debug1: sshd version OpenSSH_5.3p1
debug1: read PEM private key done: type RSA
debug1: private host key: #0 type 1 RSA
debug1: read PEM private key done: type DSA
debug1: private host key: #1 type 2 DSA
debug1: rexec_argv[0]='/usr/sbin/sshd'
debug1: rexec_argv[1]='-d'
debug1: Bind to port 22 on 0.0.0.0.
Server listening on 0.0.0.0 port 22.
debug1: Bind to port 22 on ::.
Server listening on :: port 22.
debug1: Server will not fork when running in debugging mode.
debug1: rexec start in 5 out 5 newsock 5 pipe -1 sock 8
debug1: inetd sockets after dupping: 3, 3
Connection from 172.60.254.24 port 53401
debug1: Client protocol version 2.0; client 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_5.3
debug1: permanently_set_uid: 74/74
debug1: list_hostkey_types: ssh-rsa,ssh-dss
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: kex: server->client aes128-ctr hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST received
debug1: SSH2_MSG_KEX_DH_GEX_GROUP sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_INIT
debug1: SSH2_MSG_KEX_DH_GEX_REPLY sent
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
debug1: KEX done
debug1: userauth-request for user root service ssh-connection method none
debug1: attempt 0 failures 0
debug1: PAM: initializing for "root"
debug1: userauth-request for user root service ssh-connection method publickey
debug1: attempt 1 failures 0
debug1: test whether pkalg/pkblob are acceptable
debug1: PAM: setting PAM_RHOST to "172.60.254.24"
debug1: PAM: setting PAM_TTY to "ssh"
debug1: temporarily_use_uid: 0/0 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: fd 4 clearing O_NONBLOCK
debug1: matching key found: file /root/.ssh/authorized_keys, line 1
Found matching RSA key: db:b3:b9:b1:c9:df:6d:e1:03:5b:57:d3:d9:c4:4e:5c
debug1: restore_uid: 0/0
Postponed publickey for root from 172.60.254.24 port 53401 ssh2
debug1: userauth-request for user root service ssh-connection method publickey
debug1: attempt 2 failures 0
debug1: temporarily_use_uid: 0/0 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: fd 4 clearing O_NONBLOCK
debug1: matching key found: file /root/.ssh/authorized_keys, line 1
Found matching RSA key: db:b3:b9:b1:c9:df:6d:e1:03:5b:57:d3:d9:c4:4e:5c
debug1: restore_uid: 0/0
debug1: ssh_rsa_verify: signature correct
debug1: do_pam_account: called
Accepted publickey for root from 172.60.254.24 port 53401 ssh2
debug1: monitor_child_preauth: root has been authenticated by privileged process
debug1: temporarily_use_uid: 0/0 (e=0/0)
debug1: ssh_gssapi_storecreds: Not a GSSAPI mechanism
debug1: restore_uid: 0/0
debug1: SELinux support enabled
debug1: PAM: establishing credentials
PAM: pam_open_session(): Authentication failure
debug1: Entering interactive session for SSH2.
debug1: server_init_dispatch_20
debug1: server_input_channel_open: ctype session rchan 0 win 1048576 max 16384
debug1: input_session_request
debug1: channel 0: new [server-session]
debug1: session_new: session 0
debug1: session_open: channel 0
debug1: session_open: session 0: link with channel 0
debug1: server_input_channel_open: confirm session
debug1: server_input_global_request: rtype [email protected] want_reply 0
debug1: server_input_channel_req: channel 0 request pty-req reply 1
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req pty-req
debug1: Allocating pty.
debug1: session_pty_req: session 0 alloc /dev/pts/1
ssh_selinux_setup_pty: security_compute_relabel: Invalid argument
debug1: server_input_channel_req: channel 0 request shell reply 1
debug1: session_by_channel: session 0 channel 0
debug1: session_input_channel_req: session 0 req shell
debug1: Setting controlling tty using TIOCSCTTY.
debug1: Received SIGCHLD.
debug1: session_by_pid: pid 17323
debug1: session_exit_message: session 0 channel 0 pid 17323
debug1: session_exit_message: release channel 0
debug1: session_pty_cleanup: session 0 release /dev/pts/1
debug1: session_by_channel: session 0 channel 0
debug1: session_close_by_channel: channel 0 child 0
debug1: session_close: session 0 pid 0
debug1: channel 0: free: server-session, nchannels 1
Received disconnect from 172.60.254.24: 11: disconnected by user
debug1: do_cleanup
debug1: PAM: cleanup
debug1: PAM: deleting credentials
