(This question had been erroneously asked in stack overflow -- I'm sorry for that -- and closed as "off topic")
I have no clue on how this happens. The distro is Scientific Linux 6.1 and everything is set up to perform authentication via public key. Yet, when sshd is running as a daemon (service sshd start), it doesn't accept public keys. (To obtain this piece of log, I've changed the sshd script to add the -ddd option)
debug1: trying public key file /root/.ssh/authorized_keys debug1: restore_uid: 0/0 debug1: temporarily_use_uid: 0/0 (e=0/0) debug1: trying public key file /root/.ssh/authorized_keys2 debug1: restore_uid: 0/0 Failed publickey for root from xxx.xxx.xxx.xxx port xxxxx ssh2 debug3: mm_answer_keyallowed: key 0x7f266e1a8840 is not allowed debug3: mm_request_send entering: type 22 debug3: mm_request_receive entering debug2: userauth_pubkey: authenticated 0 pkalg ssh-rsa debug3: Wrote 64 bytes for a total of 1853 debug1: userauth-request for user root service ssh-connection method publickey debug1: attempt 2 failures 1
If sshd is run in debug mode (/usr/sbin/sshd -ddd), authentication works like a charm:
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: d7:3a:08:39:f7:28:dc:ea:f3:71:7c:23:92:02:02:d8 debug1: restore_uid: 0/0 debug3: mm_answer_keyallowed: key 0x7f85527ef230 is allowed debug3: mm_request_send entering: type 22 debug3: mm_request_receive entering debug3: Wrote 320 bytes for a total of 2109 debug2: userauth_pubkey: authenticated 0 pkalg ssh-rsa Postponed publickey for root from xxx.xxx.xxx.xxx port xxxxx ssh2 debug1: userauth-request for user root service ssh-connection method publickey debug1: attempt 2 failures 0
Any ideas?? Has anyone seen anything like this?
File permissions have been double checked:
# ll -d .ssh drwx------. 2 root root 4096 Oct 14 10:05 .ssh # ll .ssh total 16 -rw-------. 1 root root 786 Oct 14 09:35 authorized_keys -rw-------. 1 root root 1675 Oct 13 08:24 id_rsa -rw-r--r--. 1 root root 393 Oct 13 08:24 id_rsa.pub -rw-r--r--. 1 root root 448 Oct 13 12:51 known_hosts
I was asked if sshd can access root's files in "daemon mode". The closest answer I get to this question is:
# netstat -ntap | grep 22 tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 19847/sshd # ps -ef | grep 19847 root 19847 1 0 09:58 ? 00:00:00 /usr/sbin/sshd
If sshd is running as root, I don't know how it's not possible to access its own files. Could SELinux be the cause?