Author Topic: ssh refused on external IP  (Read 872 times)

Offline shimonl

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ssh refused on external IP
« on: July 18, 2012, 01:51:59 AM »
Hi,
I am trying to set up ssh on my home PCLOS.

I have sshd up and running from boot. (Image below)
Port 22 open in my router. (Images of port scan below)
ssh open in the PCLOS firewall. (Image below)

I am quite able to connect to myself with ssh, if I use either the loopback address,
or my PC's LAN address. (Logs below for convenience).

When I try to connect to myself via my external IP, I get Connection refused.

Can anyone tell me why?

Thanks!!

Here are the various screenshots and logs.

1. sshd is up:


2. I don't know what you think of GRC, but he does say my port 22 is open.



3. SSH open in PCLOS firewall:


4. logs of the three attempts, all with -vvv:

Using address 127.0.0.1
Quote
[home-username@localhost ~]$ ssh -vvv -l home-username 127.0.0.1
OpenSSH_5.9p2, OpenSSL 1.0.0e 6 Sep 2011
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 49: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 127.0.0.1 [127.0.0.1] port 22.
debug1: Connection established.
debug1: identity file /home/home-username/.ssh/identity type -1
debug1: identity file /home/home-username/.ssh/identity-cert type -1
debug1: identity file /home/home-username/.ssh/id_rsa type -1
debug1: identity file /home/home-username/.ssh/id_rsa-cert type -1
debug1: identity file /home/home-username/.ssh/id_dsa type -1
debug1: identity file /home/home-username/.ssh/id_dsa-cert type -1
debug1: identity file /home/home-username/.ssh/id_ecdsa type -1
debug1: identity file /home/home-username/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9
debug1: match: OpenSSH_5.9 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "127.0.0.1" from file "/home/home-username/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/home-username/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,ssh-dss-cert-v00@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: RSA 27:bf:(etc etc):ea:b8:71
debug3: load_hostkeys: loading entries for host "127.0.0.1" from file "/home/home-username/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/home-username/.ssh/known_hosts:5
debug3: load_hostkeys: loaded 1 keys
debug1: Host '127.0.0.1' is known and matches the RSA host key.
debug1: Found key in /home/home-username/.ssh/known_hosts:5
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/home-username/.ssh/identity ((nil))
debug2: key: /home/home-username/.ssh/id_rsa ((nil))
debug2: key: /home/home-username/.ssh/id_dsa ((nil))
debug2: key: /home/home-username/.ssh/id_ecdsa ((nil))
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/home-username/.ssh/identity
debug3: no such identity: /home/home-username/.ssh/identity
debug1: Trying private key: /home/home-username/.ssh/id_rsa
debug3: no such identity: /home/home-username/.ssh/id_rsa
debug1: Trying private key: /home/home-username/.ssh/id_dsa
debug3: no such identity: /home/home-username/.ssh/id_dsa
debug1: Trying private key: /home/home-username/.ssh/id_ecdsa
debug3: no such identity: /home/home-username/.ssh/id_ecdsa
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred: password
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug2: userauth_kbdint
debug2: we sent a keyboard-interactive packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: userauth_kbdint: disable: no info_req_seen
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred:
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
home-username@127.0.0.1's password:
debug3: packet_send2: adding 64 (len 60 padlen 4 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
Authenticated to 127.0.0.1 ([127.0.0.1]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug2: callback start
debug2: x11_get_proto: /usr/bin/xauth  list :0 2>/dev/null
debug1: Requesting X11 forwarding with authentication spoofing.
debug2: channel 0: request x11-req confirm 1
debug2: client_session2_setup: id 0
debug2: fd 3 setting TCP_NODELAY
debug2: channel 0: request pty-req confirm 1
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: X11 forwarding request accepted on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Last login: Wed Jul 18 09:56:10 2012 from localhost.mypc
[home-username@localhost ~]$ debug2: channel 0: filter stops
debug2: channel 0: read failed
debug2: channel 0: close_read
debug2: channel 0: input open -> drain
debug1: channel 0: free: client-session, nchannels 1
debug3: channel 0: status: The following connections are open:
  #0 client-session (t4 r0 i1/0 o0/0 fd -1/5 cc -1)

Connection to 127.0.0.1 closed.
Transferred: sent 2248, received 2112 bytes, in 128.6 seconds
Bytes per second: sent 17.5, received 16.4
debug1: Exit status -1


Using LAN address 10.1.20.5
Quote
[home-username@localhost ~]$ ssh -vvv -l home-username 10.1.20.5
OpenSSH_5.9p2, OpenSSL 1.0.0e 6 Sep 2011
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 49: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to 10.1.20.5 [10.1.20.5] port 22.
debug1: Connection established.
debug1: identity file /home/home-username/.ssh/identity type -1
debug1: identity file /home/home-username/.ssh/identity-cert type -1
debug1: identity file /home/home-username/.ssh/id_rsa type -1
debug1: identity file /home/home-username/.ssh/id_rsa-cert type -1
debug1: identity file /home/home-username/.ssh/id_dsa type -1
debug1: identity file /home/home-username/.ssh/id_dsa-cert type -1
debug1: identity file /home/home-username/.ssh/id_ecdsa type -1
debug1: identity file /home/home-username/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9
debug1: match: OpenSSH_5.9 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "10.1.20.5" from file "/home/home-username/.ssh/known_hosts"
debug3: load_hostkeys: loaded 0 keys
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-dss-cert-v00@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: RSA 27:bf:7b:(etc etc):ea:b8:71
debug3: load_hostkeys: loading entries for host "10.1.20.5" from file "/home/home-username/.ssh/known_hosts"
debug3: load_hostkeys: loaded 0 keys
Warning: Permanently added '10.1.20.5' (RSA) to the list of known hosts.
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/home-username/.ssh/identity ((nil))
debug2: key: /home/home-username/.ssh/id_rsa ((nil))
debug2: key: /home/home-username/.ssh/id_dsa ((nil))
debug2: key: /home/home-username/.ssh/id_ecdsa ((nil))
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/home-username/.ssh/identity
debug3: no such identity: /home/home-username/.ssh/identity
debug1: Trying private key: /home/home-username/.ssh/id_rsa
debug3: no such identity: /home/home-username/.ssh/id_rsa
debug1: Trying private key: /home/home-username/.ssh/id_dsa
debug3: no such identity: /home/home-username/.ssh/id_dsa
debug1: Trying private key: /home/home-username/.ssh/id_ecdsa
debug3: no such identity: /home/home-username/.ssh/id_ecdsa
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred: password
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug2: userauth_kbdint
debug2: we sent a keyboard-interactive packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: userauth_kbdint: disable: no info_req_seen
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred:
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
home-username@10.1.20.5's password:
debug3: packet_send2: adding 64 (len 60 padlen 4 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
Authenticated to 10.1.20.5 ([10.1.20.5]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug2: callback start
debug2: x11_get_proto: /usr/bin/xauth  list :0 2>/dev/null
debug1: Requesting X11 forwarding with authentication spoofing.
debug2: channel 0: request x11-req confirm 1
debug2: client_session2_setup: id 0
debug2: fd 3 setting TCP_NODELAY
debug2: channel 0: request pty-req confirm 1
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: X11 forwarding request accepted on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Last login: Wed Jul 18 10:20:42 2012 from localhost.mypc
[home-username@localhost ~]$ debug2: channel 0: filter stops
debug2: channel 0: read failed
debug2: channel 0: close_read
debug2: channel 0: input open -> drain
debug1: channel 0: free: client-session, nchannels 1
debug3: channel 0: status: The following connections are open:
  #0 client-session (t4 r0 i1/0 o0/0 fd -1/5 cc -1)

Connection to 10.1.20.5 closed.
Transferred: sent 2248, received 2112 bytes, in 2.9 seconds
Bytes per second: sent 782.9, received 735.5
debug1: Exit status -1


But failure using external IP. All occurrences below of 'x.x.x.x' are the same IP.
Quote
[home-username@localhost ~]$ ssh -vvv -l home-username x.x.x.x
OpenSSH_5.9p2, OpenSSL 1.0.0e 6 Sep 2011
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 49: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to x.x.x.x. [x.x.x.x.] port 22.
debug1: connect to address x.x.x.x. port 22: Connection refused
ssh: connect to host x.x.x.x. port 22: Connection refused


« Last Edit: July 18, 2012, 08:39:06 AM by shimonl »

Offline Phil

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Re: ssh refused on external IP
« Reply #1 on: July 18, 2012, 01:58:16 AM »
Is the router forwarding the port 22 ssh to your machine, port forwarding?


Offline shimonl

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  • Posts: 155
Re: ssh refused on external IP
« Reply #2 on: July 18, 2012, 02:08:59 AM »
It certainly looks like it is. The port is open, and I see no possibility of
rerouting a port to a different one.

The SSH service is defined, and the rule routing it to my LAN ip is enabled.





Thank you,
Shimon

Offline Phil

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Re: ssh refused on external IP
« Reply #3 on: July 18, 2012, 03:17:40 AM »
Thank you for the screenshots. When I get a raspberrypi I may set up ssh so that is useful for me

Offline kjpetrie

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Re: ssh refused on external IP
« Reply #4 on: July 18, 2012, 05:01:50 AM »
Does /etc/ssh/sshd_config accept connections for shimon from the Internet? (As you intend to open ssh from the Internet you might want to consider changing that name to one you haven't published on an open forum, as it is easy to pummel that port with shimon and a different one-valid-character-changed-at-a-time password at 1 second intervals until the connection succeeds. Then repeat the same technique with su to gain full control of your machine.)

Have you looked in /var/log/messages etc. for any reference to the connection attempts. If they are recorded there you are reaching the machine. They might also give information on why it's not connecting.
-----------
KJP
-----------------------------------------------------------
PClos64 RC1 on Intel D945GCLF2 motherboard (Atom 330), 2GB DDR2 RAM, Maxtor STM325031, HL-DT-ST DVDRAM GSA-H42N, Amilo LSL 3220T monitor. Also Acer 5810TG (with custom kernel) and Asus eeePC 2G surf

Offline shimonl

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Re: ssh refused on external IP
« Reply #5 on: July 18, 2012, 08:27:02 AM »
Apparently my problem is more of a curiosity than a real "problem",
since I *am* able to connect to my home machine from a foreign host.
I don't have any idea why it should work from this computer and not work from
my own at home, but that is the case (log included below, if anyone wants
to explain the reason to me).

Regarding the security exposure, I appreciate the good advice, kjpetrie.
However, I am not sure I see the danger. While I did not mask my userid,
and maybe I really should have, of what actual use is it to hackers/crackers/assorted_bad_guys
if I have hidden my IP address? How would anyone know *where* in the whole wide
Internet world to hit on my userid?

Anyway, when I get home again, I will look at /etc/ssh/sshd_config and /var/log/messages etc.
to see if there is anything interesting there.

Thank you all!
Shimon

Log of successful ssh from remote computer.
the target IP of x.x.x.x is the same IP as in my previous logs.
This time I replaced real userids with fictitious ones (I will go back and modify the other logs as well)

Quote
[user-on-remote@@localhost ~]$ ssh -vvv home-username@x.x.x.x
OpenSSH_5.9p2, OpenSSL 1.0.0e 6 Sep 2011
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 49: Applying options for *
debug2: ssh_connect: needpriv 0
debug1: Connecting to x.x.x.x [x.x.x.x] port 22.
debug1: Connection established.
debug1: identity file /home/user-on-remote/.ssh/identity type -1
debug1: identity file /home/user-on-remote/.ssh/identity-cert type -1
debug1: identity file /home/user-on-remote/.ssh/id_rsa type -1
debug1: identity file /home/user-on-remote/.ssh/id_rsa-cert type -1
debug1: identity file /home/user-on-remote/.ssh/id_dsa type -1
debug1: identity file /home/user-on-remote/.ssh/id_dsa-cert type -1
debug1: identity file /home/user-on-remote/.ssh/id_ecdsa type -1
debug1: identity file /home/user-on-remote/.ssh/id_ecdsa-cert type -1
debug1: Remote protocol version 2.0, remote software version OpenSSH_5.9
debug1: match: OpenSSH_5.9 pat OpenSSH*
debug1: Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_5.9
debug2: fd 3 setting O_NONBLOCK
debug3: load_hostkeys: loading entries for host "x.x.x.x" from file "/home/user-on-remote/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/user-on-remote/.ssh/known_hosts:2
debug3: load_hostkeys: loaded 1 keys
debug3: order_hostkeyalgs: prefer hostkeyalgs: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-rsa,ecdsa-sha2-nistp256-cert-v01@openssh.com,ecdsa-sha2-nistp384-cert-v01@openssh.com,ecdsa-sha2-nistp521-cert-v01@openssh.com,ssh-dss-cert-v01@openssh.com,ssh-dss-cert-v00@openssh.com,ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit: none,zlib@openssh.com,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group-exchange-sha256,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-256-96,hmac-sha2-512,hmac-sha2-512-96,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit: none,zlib@openssh.com
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_setup: found hmac-md5
debug1: kex: server->client aes128-ctr hmac-md5 none
debug2: mac_setup: found hmac-md5
debug1: kex: client->server aes128-ctr hmac-md5 none
debug1: sending SSH2_MSG_KEX_ECDH_INIT
debug1: expecting SSH2_MSG_KEX_ECDH_REPLY
debug1: Server host key: RSA 27:bf:7b:9c:9c:(etc etc):71:8a
debug3: load_hostkeys: loading entries for host "x.x.x.x" from file "/home/user-on-remote/.ssh/known_hosts"
debug3: load_hostkeys: found key type RSA in file /home/user-on-remote/.ssh/known_hosts:2
debug3: load_hostkeys: loaded 1 keys
debug1: Host 'x.x.x.x' is known and matches the RSA host key.
debug1: Found key in /home/user-on-remote/.ssh/known_hosts:2
debug1: ssh_rsa_verify: signature correct
debug2: kex_derive_keys
debug2: set_newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: expecting SSH2_MSG_NEWKEYS
debug2: set_newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: Roaming not allowed by server
debug1: SSH2_MSG_SERVICE_REQUEST sent
debug2: service_accept: ssh-userauth
debug1: SSH2_MSG_SERVICE_ACCEPT received
debug2: key: /home/user-on-remote/.ssh/identity ((nil))
debug2: key: /home/user-on-remote/.ssh/id_rsa ((nil))
debug2: key: /home/user-on-remote/.ssh/id_dsa ((nil))
debug2: key: /home/user-on-remote/.ssh/id_ecdsa ((nil))
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: start over, passed a different list publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Trying private key: /home/user-on-remote/.ssh/identity
debug3: no such identity: /home/user-on-remote/.ssh/identity
debug1: Trying private key: /home/user-on-remote/.ssh/id_rsa
debug3: no such identity: /home/user-on-remote/.ssh/id_rsa
debug1: Trying private key: /home/user-on-remote/.ssh/id_dsa
debug3: no such identity: /home/user-on-remote/.ssh/id_dsa
debug1: Trying private key: /home/user-on-remote/.ssh/id_ecdsa
debug3: no such identity: /home/user-on-remote/.ssh/id_ecdsa
debug2: we did not send a packet, disable method
debug3: authmethod_lookup keyboard-interactive
debug3: remaining preferred: password
debug3: authmethod_is_enabled keyboard-interactive
debug1: Next authentication method: keyboard-interactive
debug2: userauth_kbdint
debug2: we sent a keyboard-interactive packet, wait for reply
debug1: Authentications that can continue: publickey,password,keyboard-interactive
debug3: userauth_kbdint: disable: no info_req_seen
debug2: we did not send a packet, disable method
debug3: authmethod_lookup password
debug3: remaining preferred:
debug3: authmethod_is_enabled password
debug1: Next authentication method: password
home-username@x.x.x.x's password:
debug3: packet_send2: adding 64 (len 60 padlen 4 extra_pad 64)
debug2: we sent a password packet, wait for reply
debug1: Authentication succeeded (password).
Authenticated to x.x.x.x ([x.x.x.x]:22).
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug2: channel 0: send open
debug1: Requesting no-more-sessions@openssh.com
debug1: Entering interactive session.
debug2: callback start
debug2: x11_get_proto: /usr/bin/xauth  list :0 2>/dev/null
debug1: Requesting X11 forwarding with authentication spoofing.
debug2: channel 0: request x11-req confirm 1
debug2: client_session2_setup: id 0
debug2: fd 3 setting TCP_NODELAY
debug2: channel 0: request pty-req confirm 1
debug2: channel 0: request shell confirm 1
debug2: callback done
debug2: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel_input_status_confirm: type 99 id 0
debug2: X11 forwarding request accepted on channel 0
debug2: channel_input_status_confirm: type 99 id 0
debug2: PTY allocation request accepted on channel 0
debug2: channel 0: rcvd adjust 2097152
debug2: channel_input_status_confirm: type 99 id 0
debug2: shell request accepted on channel 0
Last login: Wed Jul 18 12:55:29 2012 from localhost.mypc
[home-username@localhost ~]$