RE: Help with OpenSSH -> SSH2 Server

From: <dhiraj.2.bhuyan(at)bt.com>
Date: Wed May 21 2003 - 04:32:06 EDT

I think the problem is at the server end - check the directory permissions. Also have a look at "/var/log/secure" and see if there is any error logged.

If for example "/home/user/.ssh/authorizes_keys" is the path to your public key on the server, the permissions using which I got it working are -

1. chmod 0700 /home/user/.ssh/authorized_keys (check the group/owner)
2. chmod 0700 /home/user/.ssh
3. chmod 0700 /home/user

dhiraj

-----Original Message-----

From: wjnorth [mailto:wjnorth@earthlink.net] Sent: 20 May 2003 15:41
To: 'Andrew n marshall'; 'secureshell'
Subject: RE: Help with OpenSSH -> SSH2 Server

What are you trying to do? Key authentication or password challenge?

Those debug1 messages are fine, its trying to associate a public key with whatever private key you own, to see if it can match them together and allow authentication through. Remember, the server's authorized_keys file contains whatever public key you want to use for key based authentication (there are a couple other ways to go about this, but this works great). It will read that file and attempt to match a private key with that public key and allow authentication through. At least, that's what I understand it to be doing. ;-)

The permission denied message is rather interesting. What do you have setup in your sshd_config file? Are you attempting to use key based authentication? If so, how did you set it up?

If you are using authorized_keys for authentication, make sure the file perms are set to 644, no matter what, openSSH sometimes farckles with permissions on key stores.

-Wes

-----Original Message-----

From: Andrew n marshall [mailto:invysibleman@yahoo.com] Sent: Monday, May 19, 2003 12:33 PM
To: secureshell
Subject: RE: Help with OpenSSH -> SSH2 Server

I'm still having the previously mentioned problems. But here is a new data point... the verbose log. The only thing strange I see is near the bottom:

  debug1: next auth method to try is publickey
  debug1: try privkey: /Users/user/.ssh/id_rsa
  debug1: try pubkey: /Users/user/.ssh/id_dsa

~/.ssh/id_dsa is a PRIVATE key (the public key would be id_dsa.pub). Why is it reading it as a pubkey?

I also glanced at the file permissions, and they match my expectations (600 for private, and 644 for public).

Anm

---

user@client:~/ > ssh -v server
OpenSSH_3.5p1, SSH protocols 1.5/2.0, OpenSSL 0x0090701f

debug1: Reading configuration data /Users/user/.ssh/config
debug1: Reading configuration data /sw/etc/ssh/ssh_config
debug1: Rhosts Authentication disabled, originating port will not be

trusted.

debug1: ssh_connect: needpriv 0
debug1: Connecting to server [192.168.208.207] port 22.
debug1: Connection established.
debug1: identity file /Users/amarshal/.ssh/identity type 0
debug1: identity file /Users/amarshal/.ssh/id_rsa type -1
debug1: identity file /Users/amarshal/.ssh/id_dsa type 2
debug1: Remote protocol version 1.99, remote software version 2.4.0 SSH

Secure Shell (non-commercial)

debug1: match: 2.4.0 SSH Secure Shell (non-commercial) pat 2.*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_3.5p1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug1: kex: server->client 3des-cbc hmac-md5 none
debug1: kex: client->server 3des-cbc hmac-md5 none
debug1: dh_gen_key: priv key bits set: 186/384
debug1: bits set: 526/1024
debug1: sending SSH2_MSG_KEXDH_INIT
debug1: expecting SSH2_MSG_KEXDH_REPLY
debug1: Host 'nitro' is known and matches the DSA host key.
debug1: Found key in /Users/user/.ssh/known_hosts:1
debug1: bits set: 506/1024
debug1: ssh_dss_verify: signature correct
debug1: kex_derive_keys
debug1: newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: waiting for SSH2_MSG_NEWKEYS
debug1: newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: done: ssh_kex2.
debug1: send SSH2_MSG_SERVICE_REQUEST
debug1: service_accept: ssh-userauth
debug1: got SSH2_MSG_SERVICE_ACCEPT
debug1: authentications that can continue: publickey
debug1: next auth method to try is publickey
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debug1: try privkey: /Users/user/.ssh/id_rsa
debug1: try pubkey: /Users/user/.ssh/id_dsa
debug1: authentications that can continue: publickey
debug1: no more auth methods to try

Permission denied (publickey).
debug1: Calling cleanup 0x17770(0x0)

---

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