Enabling remote SSH access in OpenWRT is a two-step process. SSH access must be enabled on the WAN, and the SSH port must be opened in the firewall.
1. Enable ssh access on the WAN Go to System->Administration. Under SSH Access, make sure "unspecified" is selected for Interface. This allows SSH access on both the LAN and WAN interfaces.
2. Now, open the appropriate port in your firewall. There are two ways to accomplish this. You can either add changes to /etc/firewall.user or /etc/config/firewall.
A. To use the first method, add the following lines to /etc/firewall.user. Note the example below specifies port 22 as the SSH port.
iptables -t nat -A prerouting_wan -p tcp --dport 22 -j ACCEPT iptables -A input_wan -p tcp --dport 22 -j ACCEPT
option name 'WAN-MGMT-80'
option src 'wan'
option dest_port '80'
option target 'ACCEPT'
option proto tcp