Right, so I wanted to setup a trust based public key authentication system between two computers in my network. When I try to ssh to the server, this happens:
Code:
dcowsill@compaq ~ $ ssh -v -l dcowsill -i .ssh/id_rsa 192.168.0.102
OpenSSH_4.5p1, OpenSSL 0.9.8d 28 Sep 2006
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: Connecting to 192.168.0.102 [192.168.0.102] port 22.
debug1: Connection established.
debug1: identity file .ssh/id_rsa type 1
debug1: identity file /home/dcowsill/.ssh/id_rsa type 1
debug1: Remote protocol version 2.0, remote software version OpenSSH_4.5
debug1: match: OpenSSH_4.5 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.5
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client aes128-cbc hmac-md5 none
debug1: kex: client->server aes128-cbc 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: Host '192.168.0.102' is known and matches the RSA host key.
debug1: Found key in /home/dcowsill/.ssh/known_hosts:1
debug1: ssh_rsa_verify: signature correct
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug1: SSH2_MSG_NEWKEYS received
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 public key: .ssh/id_rsa
debug1: Authentications that can continue: publickey
debug1: Offering public key: /home/dcowsill/.ssh/id_rsa
debug1: Authentications that can continue: publickey
debug1: No more authentication methods to try.
Permission denied (publickey).
Basically, just the debugging information behind the last error message. My client offers the correct id_rsa file (I have verified this dozens of different ways) and the user has permission to log into the system.
Here's the output when I run sshd in debug mode:
Code:
Connection from 192.168.0.101 port 4288
debug1: Client protocol version 2.0; client software version OpenSSH_4.5
debug1: match: OpenSSH_4.5 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_4.5
debug1: permanently_set_uid: 22/22
debug1: list_hostkey_types: ssh-rsa,ssh-dss
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: kex: server->client aes128-cbc 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 dcowsill service ssh-connection method none
debug1: attempt 0 failures 0
debug1: PAM: initializing for "dcowsill"
debug1: userauth-request for user dcowsill service ssh-connection method publickey
debug1: attempt 1 failures 1
debug1: test whether pkalg/pkblob are acceptable
debug1: PAM: setting PAM_RHOST to "192.168.0.101"
debug1: PAM: setting PAM_TTY to "ssh"
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: restore_uid: 0/0
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: restore_uid: 0/0
Failed publickey for dcowsill from 192.168.0.101 port 4288 ssh2
debug1: userauth-request for user dcowsill service ssh-connection method publickey
debug1: attempt 2 failures 2
debug1: test whether pkalg/pkblob are acceptable
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: restore_uid: 0/0
debug1: temporarily_use_uid: 1000/1000 (e=0/0)
debug1: trying public key file /root/.ssh/authorized_keys
debug1: restore_uid: 0/0
Failed publickey for dcowsill from 192.168.0.101 port 4288 ssh2
Connection closed by 192.168.0.101
As you can see, the server does not actually look for the correct public key. The server looks for root's public key (which does not actually exist). This means that public key authentication fails every time. I have looked over my sshd_config file many times looking for the cause, and as you can see it is changed very little from the default:
Code:
# $OpenBSD: sshd_config,v 1.74 2006/07/19 13:07:10 dtucker Exp $
# This is the sshd server system-wide configuration file. See
# sshd_config(5) for more information.
# This sshd was compiled with PATH=/usr/bin:/bin:/usr/sbin:/sbin
# The strategy used for options in the default sshd_config shipped with
# OpenSSH is to specify options with their default value where
# possible, but leave them commented. Uncommented options change a
# default value.
Port 22
Protocol 2
#AddressFamily any
ListenAddress 192.168.0.102
#ListenAddress ::
# HostKey for protocol version 1
#HostKey /etc/ssh/ssh_host_key
# HostKeys for protocol version 2
#HostKey /etc/ssh/ssh_host_rsa_key
#HostKey /etc/ssh/ssh_host_dsa_key
# Lifetime and size of ephemeral version 1 server key
#KeyRegenerationInterval 1h
#ServerKeyBits 768
# Logging
# obsoletes QuietMode and FascistLogging
SyslogFacility AUTH
LogLevel INFO
# Authentication:
#LoginGraceTime 2m
PermitRootLogin no
#StrictModes yes
#MaxAuthTries 6
RSAAuthentication yes
PubkeyAuthentication yes
AuthorizedKeysFile ~/.ssh/authorized_keys
DenyGroups all
AllowGroups sshd
# For this to work you will also need host keys in /etc/ssh/ssh_known_hosts
#RhostsRSAAuthentication no
# similar for protocol version 2
#HostbasedAuthentication no
# Change to yes if you don't trust ~/.ssh/known_hosts for
# RhostsRSAAuthentication and HostbasedAuthentication
#IgnoreUserKnownHosts no
# Don't read the user's ~/.rhosts and ~/.shosts files
#IgnoreRhosts yes
# To disable tunneled clear text passwords, change to no here!
PasswordAuthentication no
#PermitEmptyPasswords no
# Change to no to disable s/key passwords
ChallengeResponseAuthentication no
# Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#KerberosTicketCleanup yes
#KerberosGetAFSToken no
# GSSAPI options
#GSSAPIAuthentication no
#GSSAPICleanupCredentials yes
# Set this to 'yes' to enable PAM authentication, account processing,
# and session processing. If this is enabled, PAM authentication will
# be allowed through the ChallengeResponseAuthentication and
# PasswordAuthentication. Depending on your PAM configuration,
# PAM authentication via ChallengeResponseAuthentication may bypass
# the setting of "PermitRootLogin without-password".
# If you just want the PAM account and session checks to run without
# PAM authentication, then enable this but set PasswordAuthentication
# and ChallengeResponseAuthentication to 'no'.
UsePAM yes
#AllowTcpForwarding yes
#GatewayPorts no
#X11Forwarding no
#X11DisplayOffset 10
#X11UseLocalhost yes
PrintMotd yes
#PrintLastLog yes
#TCPKeepAlive yes
#UseLogin no
#UsePrivilegeSeparation yes
#PermitUserEnvironment no
#Compression delayed
#ClientAliveInterval 0
#ClientAliveCountMax 3
#UseDNS yes
#PidFile /var/run/sshd.pid
#MaxStartups 10
#PermitTunnel no
# no default banner path
#Banner /some/path
# override default of no subsystems
Subsystem sftp /usr/lib64/misc/sftp-server
# Example of overriding settings on a per-user basis
#Match User anoncvs
# X11Forwarding no
# AllowTcpForwarding no
# ForceCommand cvs server
I can confirm that the ssh_config file on the client machine is absolutely default.
I am sorry about the verbosity of my post, but every little bit helps. This problem is absolutely baffling to me, so I would appreciate further insights.
Thank you very much.
