| # http://www.aliexpress.com/item/New-Mini-Portable-Wireless-3G-Router-TP-LINK-TL-WR703N-150M-150Mbps-WR703N-Pocket-size-Wifi/948558329.html | |
| # Someone should convince TP-Link to build this with more Flash, serial headers, bare board, *duino style... | |
| # This is the starting point for a webradio appliance in the works | |
| # TODO: Preconfigure everything, hook up Arduino for IR control sending and receiving | |
| wget http://downloads.openwrt.org/attitude_adjustment/12.09/ar71xx/generic/OpenWrt-ImageBuilder-ar71xx_generic-for-linux-i486.tar.bz2 | |
| tar xfj OpenWrt-ImageBuilder* | |
| cd "$HOME/Downloads/OpenWrt-ImageBuilder-ar71xx_generic-for-linux-i486" |
| Requirements: | |
| Winbond W25Q128FV (or other compatible chip, see pepe2k's uboot readme) | |
| SPI Programmer (ie a Revelprog IS) | |
| Serial Console (ie a CP2102) | |
| HEX editor (ie Bless) | |
| 32bit vm to compile pepe2k's uboot | |
| tftp server | |
| Note: I already had pepe2k's uboot + LEDE r930 flashed on the original 4MiB flash chip. I assume I made a mistake with the data partition due to already having pepe2k's uboot installed. More is explained later on. |
Recently, I did a bit of shuffling around with my devices. My dad wanted wifi he can carry around. So I gave him the Huwaie portable router and my brother got my wall plugged 3G dongle and I was left with my trusty ol' TP-LINK-MR3020. Since I use 3G myself, I decided I would utilise the TP-LINK and so got a NETGEAR dongle without inbuilt wifi instead of a new 3g/4G dongle (cause it was cheaper and won't interfere with TP-LINK's wifi signal). Then in a hurry to get my router to work I flashed it with the upgrade firmware and something went wrong along the way and it bricked the device (3 lights blinking intermittently).
The way to prop it back to life is to to get a serial connection from the device. This involves prying open the device (voids warranty but the concept of warranty itself is mostly useless anyway).
There are two ways to go about this:
| Run the following: | |
| iptables -A INPUT -m pkttype --pkt-type multicast -j ACCEPT | |
| iptables -A FORWARD -m pkttype --pkt-type multicast -j ACCEPT | |
| iptables -A OUTPUT -m pkttype --pkt-type multicast -j ACCEPT | |
| Or: | |
| iptables -A INPUT -s 224.0.0.0/4 -j ACCEPT | |
| iptables -A FORWARD -s 224.0.0.0/4 -d 224.0.0.0/4 -j ACCEPT |
Turns out, UPnP is terrible when it comes to security. The entire protocol exists to have devices easily find and connect to one another without any authentication at all. This is all good fun to poke around with. Here are a few tools and notes I've found along the way.
UPnP devices can be found by listening to UDP packets on port 1900. To actively discover these services on your network, send an HTTP M-SEARCH request to the default UDP mulicast address: 239.255.255.250.
There are some great Linux tools that make interfacing with all of these stuff a synch:
sudo apt update
| #!/bin/bash | |
| #~/bin/upnpPortMapper.sh | |
| #sudo apt-get install miniupnpc | |
| #crontab -l | grep upnp || echo $(crontab -l ; echo '*/5 * * * * ~/bin/upnpPortMapper.sh >/dev/null 2>&1') | crontab - | |
| export LC_ALL=C | |
| router=$(ip r | grep default | cut -d " " -f 3) | |
| gateway=$(upnpc -l | grep "desc: http://$router:[0-9]*/rootDesc.xml" | cut -d " " -f 3) | |
| ip=$(upnpc -l | grep "Local LAN ip address" | cut -d: -f2) |
| admin: | |
| access_log_path: /tmp/admin_access.log | |
| address: | |
| socket_address: | |
| address: 127.0.0.1 | |
| protocol: TCP | |
| port_value: 9901 | |
| static_resources: | |
| listeners: | |
| - name: listener_0 |