External SSH

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(How to set up SSH access from internet)
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-=How to set up SSH access from internet=+{{Languages|External SSH}}
 +SSH access from Internet
-To make it possible to access your router from internet by SSH follow these steps:+==Ensure SSH Enabled==
 +# Goto the ''Services'' tab and the ''Services'' sub-tab on the [[Web Interface]]
 +# Enable "SSHd" is under the section titled "Secure Shell"
 +# 'SSH TCP Forwarding' does not need to be enabled if you just want to connect from the outside to your LAN.
 +# Choose an appropriate port (The default is 22, but it is recommended that you change it to a non-standard port above 1024 for security reasons. Remember the port number, as you will need to enter it into your SSH client in order to connect to the router)
 +# You can activate (less secure) password authorization and/or (recommended) private/public key authorization. More information about generating the keys can be found here: [[http://www.dd-wrt.com/wiki/index.php/Telnet/SSH_and_the_Command_Line#Setting_Up]].
 +# Save
-00:14, 1 Jul 2006 (CEST) [http://www.dd-wrt.com/phpBB2/profile.php?mode=viewprofile&u=810 pagedude]+==Enable Remote Access==
 +# Goto the ''Administration'' tab and the ''Management'' sub-tab on the [[Web Interface]]
 +# Enable "SSH Management" under the section titled "Remote Access"
 +# Enter the same port number as specified under (4) above. This opens the port in the firewall.
 +# Save
 +# Reboot Router
 +Now you will be able to connect to your router's WAN IP from the internet using an SSH client such as [http://www.chiark.greenend.org.uk/~sgtatham/putty/ PuTTY].
-SSH Web administration has been highly simplified and streamlined in V23SP1; no firewall configuration or scripting is necessary, everything is available through the UI.+==Disabling Remote Access==
 +If at any time you wish to disable SSH access from the WAN,
 +# Goto the ''Administration'' tab and the ''Management'' sub-tab on the [[Web Interface]]
 +# Disable "SSH Management" under the section titled "Remote Access"
 +# Apply Settings
-*First make sure the SSH daemon gets started. Goto Adminstration->Services and look for the section titled "Secure Shell", and check to see if "Sshd" is enabled.+==SSH Password==
-**Refer to http://www.dd-wrt.com/wiki/index.php?title=Telnet/SSH_and_the_Command_Line#SSH or Sections 1.1 and 1.2 of http://hetos.de/sshtut.html+# When asked for the '''username''', enter '''root''' (even if you changed username in web interface)
-*Now we will enable remote access to the ssh daemon. Goto Administration->Management and look for the section titled "Remote Access"+# When asked for the '''password''', enter your router's password
-**Select "Enable" for the "SSH Management" option in this section+
-**Choose an appropriate port (default port is 22)+
-**Recommend also to change the SSHD port to something non-standard above 1024. The reason for this is, there are MANY brute-force attack tools out there that scan ranges of IP looking on port 22. If they see a response they do a brute-force attempt with a list of passwords. If your password is "admin" you are likely to be in trouble. Easy way to avoid being on their radar is CHANGE THIS DEFAULT PORT. +
-**Scroll to the bottom of this page, and click "Save Settings"+
-*To log into your router from a windows machine you could use Putty (http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html). You will have to enter the external ip of your router or the DynDNS name to login from Internet. If you have changed the port on which sshd runs, you will have to fill in that port number.+
 +=References=
 +* http://hetos.de/sshtut.html
-The following instructions apply to DD-WRT V23 or earlier.+[[Category:SSH]]
- +[[Category:Basic tutorials]]
-00:14, 1 Jul 2006 (CEST) [http://www.dd-wrt.com/phpBB2/profile.php?mode=viewprofile&u=810 pagedude]+
- +
- +
-* Enable SSHD on the [[Web_Interface]] (''Administration'' -> ''Management'' or ''Services'') and don't forget to ''Save Settings''.+
-* Recommend also to change the SSHD port to something non-standard above 1024. The reason for this is, there are MANY brute-force attack tools out there that scan ranges of IP looking on port 22. If they see a response they do a brute-force attempt with a list of passwords. If your password is "admin" you are likely to be in trouble. Easy way to avoid being on their radar is CHANGE THIS DEFAULT PORT.+
-* To allow access to the SSH port from WAN add the following rule as command on the [[Web_Interface]] (''Administration'' -> ''Diagnostics'') and save with ''Save Firewall'':+
- this command is not working /usr/sbin/iptables -I INPUT 1 -p tcp --dport $(nvram get sshd_port) -j logaccept+
- the rigth syntahx is /usr/sbin/iptables -I INPUT -p tcp --dport $(nvram get sshd_port) -j logaccept+
-* To log into your router from a windows machine you could use [http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html Putty]. You will have to enter the external ip of your router or the DynDNS name to login from Internet. If you have changed the port on which sshd runs, you will have to fill in that port number.+
- +
-* To disable the access from Internet: +
- /usr/sbin/iptables -D INPUT 1+
- +
-=Warning!=+
-'''It's not too secure to set up SSH access like that. Be sure to choose a long and secure password or even better use [[Telnet/SSH_and_the_Command_Line#Setting_Up_2|Public Key Method]]. Otherwise someone could succeed to hack your router by a [http://en.wikipedia.org/wiki/Brute_force_attack Brute Force Attack].'''+
-[[Category:basic HOWTO]]+
- +
-'''The above method is obsolete at this time:''' You should only now need to go to Administration->Management->Remote Access->SSH Management and enable it, specifying the port you wish to enable WAN access to.+
- +
-[[Category:English documentation]]+

Current revision

SSH access from Internet

Contents

[edit] Ensure SSH Enabled

  1. Goto the Services tab and the Services sub-tab on the Web Interface
  2. Enable "SSHd" is under the section titled "Secure Shell"
  3. 'SSH TCP Forwarding' does not need to be enabled if you just want to connect from the outside to your LAN.
  4. Choose an appropriate port (The default is 22, but it is recommended that you change it to a non-standard port above 1024 for security reasons. Remember the port number, as you will need to enter it into your SSH client in order to connect to the router)
  5. You can activate (less secure) password authorization and/or (recommended) private/public key authorization. More information about generating the keys can be found here: [[1]].
  6. Save

[edit] Enable Remote Access

  1. Goto the Administration tab and the Management sub-tab on the Web Interface
  2. Enable "SSH Management" under the section titled "Remote Access"
  3. Enter the same port number as specified under (4) above. This opens the port in the firewall.
  4. Save
  5. Reboot Router

Now you will be able to connect to your router's WAN IP from the internet using an SSH client such as PuTTY.

[edit] Disabling Remote Access

If at any time you wish to disable SSH access from the WAN,

  1. Goto the Administration tab and the Management sub-tab on the Web Interface
  2. Disable "SSH Management" under the section titled "Remote Access"
  3. Apply Settings

[edit] SSH Password

  1. When asked for the username, enter root (even if you changed username in web interface)
  2. When asked for the password, enter your router's password

[edit] References