diff --git a/content/.obsidian/workspace.json b/content/.obsidian/workspace.json index b2a805c..185f1b0 100644 --- a/content/.obsidian/workspace.json +++ b/content/.obsidian/workspace.json @@ -37,7 +37,7 @@ "state": { "type": "markdown", "state": { - "file": "Wine Crate Coffee Table.md", + "file": "Bypassing Ports Old.md", "mode": "source", "source": false } @@ -106,7 +106,7 @@ } ], "direction": "horizontal", - "width": 300 + "width": 200 }, "right": { "id": "260bba8f76f307a9", @@ -122,7 +122,7 @@ "state": { "type": "backlink", "state": { - "file": "Wine Crate Coffee Table.md", + "file": "Bypassing Ports Old.md", "collapseAll": false, "extraContext": false, "sortOrder": "alphabetical", @@ -139,7 +139,7 @@ "state": { "type": "outline", "state": { - "file": "Wine Crate Coffee Table.md" + "file": "Bypassing Ports Old.md" } } } @@ -148,7 +148,8 @@ } ], "direction": "horizontal", - "width": 300 + "width": 300, + "collapsed": true }, "left-ribbon": { "hiddenItems": { @@ -161,13 +162,19 @@ }, "active": "d9a16803d250ddc4", "lastOpenFiles": [ + "Bypassing Ports.md", + "Bypassing Ports Old.md", + "Backup Strategy.md", + "Algae Growth.md", + "Secret Garden.md", + "Airflow.md", + "Wine Crate Coffee Table.md", "Things I Recommend.md", "t0txt.md", "t0 Services.md", "Spaceport.md", "Solar Car.md", "Sensors.md", - "Secret Garden.md", "QotNews.md", "Protospace.md", "Plant Waterer.md", @@ -181,12 +188,6 @@ "Hydroponics Log 2.md", "Hydroponics Log 1.md", "Hydroponics Aphid War.md", - "Hydroponics.md", - "Hand of Ozymandias.md", - "Garage Door Opener.md", - "Fake Dog.md", - "ChatGPT Peanut Butter Cookies.md", - "Bypassing Ports.md", "media/japan12hi.jpg", "media/japan11hi.jpg", "media/japan10hi.jpg", diff --git a/content/Bypassing Ports Old.md b/content/Bypassing Ports Old.md new file mode 100644 index 0000000..af3477a --- /dev/null +++ b/content/Bypassing Ports Old.md @@ -0,0 +1,370 @@ +Title: Bypassing ISP Blocked Ports (Old) +Date: 2021-04-10 +Category: Notes +Summary: (Old) Bypass ISP blocked ports using VPN port forwarding for public access. +Wide: true +Short: ports-old + +[TOC] + +My residential ISP blocks inbound traffic to common ports like 22, 80, and 443. I use an OpenVPN tunnel to forward these ports so that I can self-host a public media server. It does __not__ require users to be on the VPN. + +This article explains how I set it up and is targeted towards Linux sysadmins. + +## Overview + +I have a cheap $5 per month virtual server with [Digital Ocean](https://digitalocean.com) that runs Debian GNU/Linux 10. An OpenVPN server is running on this virtual server. + +My media server at home has an OpenVPN client connected to the server and is assigned a static IP on the VPN network. + +The virtual server has routing enabled and forwards inbound traffic __from the internet__ to my media server at home. This allows me to have external HTTP and SSH access. + +## Server Setup + +Spin up a Debian 10 virtual server on your favourite hosting provider and set your user up as you would normally. You should probably harden this server. Assign a subdomain to it like `vpn.example.com`. + +Install the following requirements: + +``` +$ sudo apt update +$ sudo apt install openvpn easy-rsa ufw +``` + +### OpenVPN Server + +These steps roughly follow [this guide](https://wiki.debian.org/OpenVPN#TLS-enabled_VPN). + +Generate TLS certificates and keys: + +``` +$ cd /etc/openvpn +$ sudo openvpn --genkey --secret static.key +$ sudo make-cadir easy-rsa/ +$ sudo chown -R tanner:tanner easy-rsa/ +``` + +Replace `tanner` with your Linux username, this is temporary. + +(The `.rnd` file prevents a warning) + +``` +$ cd easy-rsa/ +$ export EASYRSA_CERT_EXPIRE=36500 +$ export EASYRSA_CA_EXPIRE=36500 +$ ./easyrsa init-pki +$ head /dev/urandom > pki/.rnd +$ ./easyrsa build-ca +``` + +Enter a password you won't forget in case you want to add another client later. The Common Name you choose is not important. + +Generate Diffie–Hellman params: + +``` +$ ./easyrsa gen-dh +``` + +Generate a server cert: + +``` +$ ./easyrsa build-server-full server nopass +``` + +Generate a client cert: + +``` +$ ./easyrsa build-client-full mediaserver nopass +``` + +We make a `mediaserver` client because we want to assign a static IP to it. You need to make a different one for each client you want with a static IP. + +Also, if you want generic clients that all get dynamic IPs for use on your laptop, phone, etc. to protect you from public WiFi (like a normal VPN), create only a single extra one: + +``` +$ ./easyrsa build-client-full client nopass # optional +``` + +Leave off `nopass` if you want to password protect the config file keys when you set up a new client. + +Create the server config file `/etc/openvpn/server.conf`: + +(Can't use port 443 here since it'll be forwarded) + +``` +port 1194 +proto udp +dev tun +topology subnet +ca /etc/openvpn/easy-rsa/pki/ca.crt +cert /etc/openvpn/easy-rsa/pki/issued/server.crt +key /etc/openvpn/easy-rsa/pki/private/server.key +dh /etc/openvpn/easy-rsa/pki/dh.pem +tls-auth /etc/openvpn/static.key 0 +client-config-dir /etc/openvpn/ccd +server 10.8.0.0 255.255.255.0 +client-to-client +duplicate-cn +keepalive 10 120 +cipher AES-256-GCM +auth SHA256 +comp-lzo +max-clients 10 +user nobody +group nogroup +persist-key +persist-tun +``` + +Assign a static IP + chmod: + +``` +$ cd /etc/openvpn +$ sudo chown -R root:root easy-rsa/ +$ sudo mkdir ccd +$ sudo touch ccd/mediaserver +``` + +Replace `mediaserver` with whatever client name you used above. Edit it like so: + +(Your home server will be `10.8.0.100`) + +``` +ifconfig-push 10.8.0.100 255.255.255.0 +``` + +Test your config by running: + +``` +$ sudo openvpn --config /etc/openvpn/server.conf +``` + +If you run `ip addr` in another terminal, you should see an entry like this: + +``` +5: tun0: stuff + link/none + inet 10.8.0.1/24 brd 10.8.0.255 scope global tun0 + valid_lft forever preferred_lft forever + inet6 fe80::d9fc:b2f9:34e6:5ed2/64 scope link stable-privacy + valid_lft forever preferred_lft forever +``` + +### systemd + +If it works fine, persist OpenVPN with systemd: + +``` +$ sudo systemctl enable openvpn@server +$ sudo systemctl start openvpn@server +$ sudo systemctl daemon-reload +$ sudo service openvpn restart +``` + +Test it works by rebooting: + +``` +$ sudo reboot +$ ssh vpn.example.com +$ ip addr +``` + +### Port Forwarding + +I use `ufw` to handle the iptables rules because I use it anyway as a firewall when I harden my servers. + +Enable routing: + +``` +$ sudo sysctl net.ipv4.ip_forward=1 +``` + +Edit `/etc/sysctl.conf` to set: + +``` +net.ipv4.ip_forward=1 +``` + +Edit `/etc/default/ufw` to set: + +``` +DEFAULT_FORWARD_POLICY="ACCEPT" +``` + +Add this to the top of `/etc/ufw/before.rules`: + +``` +*nat +:POSTROUTING ACCEPT [0:0] + +# ssh port forwarding +-A PREROUTING -d 123.123.123.123 -p tcp --dport 2222 -j DNAT --to-dest 10.8.0.100:2222 +-A POSTROUTING -d 10.8.0.100 -p tcp --dport 2222 -j SNAT --to-source 10.8.0.1 + +# Allow traffic from OpenVPN client to eth0 +-A POSTROUTING -s 10.8.0.0/8 -o eth0 -j MASQUERADE +COMMIT +``` + +Replace `123.123.123.123` with your VPN server's external IP address and `eth0` with the external interface. + +This will forward TCP traffic on port 2222 to your home server. If you want to use port 22, then you need to set the VPN SSH server to something else. + +A full example of `/etc/ufw/before.rules` with other ports included can be found here: + +[https://txt.t0.vc/URUG](https://txt.t0.vc/URUG) + +Apply the changes to `ufw`: + +``` +$ sudo ufw disable && sudo ufw enable +``` + +## Client Setup + +Switch to your home server or client machine. + +Install OpenVPN: + +``` +$ sudo apt update +$ sudo apt install openvpn +``` + +### Client Configs + +For static IP clients (like your home server), create the config file `/etc/openvpn/client.conf`: + +``` +client +dev tun +proto udp +remote vpn.example.com 1194 +resolv-retry infinite +nobind +persist-key +persist-tun +remote-cert-tls server +cipher AES-256-GCM +auth SHA256 +comp-lzo +key-direction 1 + +[server /etc/openvpn/easy-rsa/pki/ca.crt] + + +[server /etc/openvpn/easy-rsa/pki/issued/mediaserver.crt] + + +[server /etc/openvpn/easy-rsa/pki/private/mediaserver.key] + + +[server /etc/openvpn/static.key] + +``` + +Replace the `[server ...]` lines with the contents of that file on the __VPN server__, for example: + +``` +$ sudo cat /etc/openvpn/easy-rsa/pki/ca.crt +---> copy & paste result +``` + +Also replace `vpn.example.com` with the subdomain you assigned earlier. + +For device clients (like your laptop and phone), create the config file `client.ovpn`: + +(`redirect-gateway def1` forces traffic over the VPN) + +``` +client +dev tun +proto udp +remote vpn.example.com 1194 +redirect-gateway def1 +resolv-retry infinite +nobind +persist-key +persist-tun +remote-cert-tls server +cipher AES-256-GCM +auth SHA256 +comp-lzo +key-direction 1 + +[server /etc/openvpn/easy-rsa/pki/ca.crt] + + +[server /etc/openvpn/easy-rsa/pki/issued/client.crt] + + +[server /etc/openvpn/easy-rsa/pki/private/client.key] + + +[server /etc/openvpn/static.key] + +``` + +The `client.ovpn` file is ready to be imported into your VPN clients. + +Test your config by running: + +``` +$ sudo openvpn --config /etc/openvpn/client.conf +``` + +If you run `ip addr` in another terminal, you should see an entry like this: + +``` +7: tun0: stuff + link/none + inet 10.8.0.100/24 brd 10.8.0.255 scope global tun0 + valid_lft forever preferred_lft forever + inet6 fe80::b2:ed71:6c98:4bc9/64 scope link stable-privacy + valid_lft forever preferred_lft forever +``` + +Try pinging the server: + +``` +$ ping 10.8.0.1 +PING 10.8.0.1 (10.8.0.1) 56(84) bytes of data. +64 bytes from 10.8.0.1: icmp_seq=1 ttl=64 time=71.5 ms +64 bytes from 10.8.0.1: icmp_seq=2 ttl=64 time=73.0 ms +... etc +``` + +### systemd + +If it works fine, persist OpenVPN with systemd: + +``` +$ sudo chown root:root /etc/openvpn/client.conf +$ sudo chmod 600 /etc/openvpn/client.conf +$ sudo systemctl enable openvpn@client +$ sudo systemctl start openvpn@client +$ sudo systemctl daemon-reload +$ sudo service openvpn restart +``` + +### Client Apps + +On Android I use "OpenVPN for Android" and on Linux I use the `network-manager-openvpn-gnome` Debian package. + +To add your VPN on Gnome, open VPN settings, import file, and select `client.ovpn`. If the private key is missing, select it from `~/.cert/nm-openvpn/`. + +## Closing Thoughts + +You should now be fine to access your home server from over the internet. + +To forward additional ports, just edit the `/etc/ufw/before.rules` file like above and apply the changes to `ufw`. + +You can now point a domain to your virtual server's IP and use that to connect to your home server. Use a CNAME to make it easy to change later: + +``` +NAME TYPE VALUE +-------------------------------------------------- +vpn.example.com. A 123.123.123.123 +myserver.example.com. CNAME vpn.example.com. +``` + +Finally, make sure any server programs are listening / bound to `10.8.0.100` or `0.0.0.0` so that they can get traffic from that interface. diff --git a/content/Bypassing Ports.md b/content/Bypassing Ports.md index 0e6d649..09dfa83 100644 --- a/content/Bypassing Ports.md +++ b/content/Bypassing Ports.md @@ -1,5 +1,5 @@ Title: Bypassing ISP Blocked Ports -Date: 2021-04-10 +Date: 2023-12-10 Category: Writing Summary: Bypass ISP blocked ports using VPN port forwarding for public access. Wide: true @@ -13,7 +13,7 @@ This article explains how I set it up and is targeted towards Linux sysadmins. ## Overview -I have a cheap $5 per month virtual server with [Digital Ocean](https://digitalocean.com) that runs Debian GNU/Linux 10. An OpenVPN server is running on this virtual server. +I have a cheap $6 per month virtual server with [Digital Ocean](https://digitalocean.com) that runs Debian GNU/Linux 12. An OpenVPN server is running on this virtual server. My media server at home has an OpenVPN client connected to the server and is assigned a static IP on the VPN network. @@ -21,42 +21,43 @@ The virtual server has routing enabled and forwards inbound traffic __from the i ## Server Setup -Spin up a Debian 10 virtual server on your favourite hosting provider and set your user up as you would normally. You should probably harden this server. Assign a subdomain to it like `vpn.example.com`. +Spin up a Debian 12 server on your favourite hosting provider. If you're using an older version of Debian, you can follow the [[Bypassing Ports Old |old version of this article]]. You should harden this server. Assign a subdomain to it like `vpn.example.com`. Install the following requirements: ``` $ sudo apt update $ sudo apt install openvpn easy-rsa ufw +$ sudo ufw allow ssh +$ sudo ufw allow 1194 # openvpn's port ``` ### OpenVPN Server -These steps roughly follow [this guide](https://wiki.debian.org/OpenVPN#TLS-enabled_VPN). +These steps roughly follow [this guide](https://wiki.debian.org/OpenVPN#TLS-enabled_VPN_connection). Generate TLS certificates and keys: ``` $ cd /etc/openvpn -$ sudo openvpn --genkey --secret static.key +$ sudo openvpn --genkey secret static.key $ sudo make-cadir easy-rsa/ -$ sudo chown -R tanner:tanner easy-rsa/ +$ sudo chown -R tanner:tanner /etc/openvpn ``` Replace `tanner` with your Linux username, this is temporary. -(The `.rnd` file prevents a warning) +(The certs will expire in 100 years) ``` $ cd easy-rsa/ $ export EASYRSA_CERT_EXPIRE=36500 $ export EASYRSA_CA_EXPIRE=36500 $ ./easyrsa init-pki -$ head /dev/urandom > pki/.rnd $ ./easyrsa build-ca ``` -Enter a password you won't forget in case you want to add another client later. The Common Name you choose is not important. +Enter passwords you won't forget in case you want to add another client later. The Common Name you choose is not important. Generate Diffie–Hellman params: @@ -70,10 +71,12 @@ Generate a server cert: $ ./easyrsa build-server-full server nopass ``` -Generate a client cert: +Generate client certs: ``` $ ./easyrsa build-client-full mediaserver nopass +$ ./easyrsa build-client-full anotherserver nopass +... etc ``` We make a `mediaserver` client because we want to assign a static IP to it. You need to make a different one for each client you want with a static IP. @@ -84,7 +87,7 @@ Also, if you want generic clients that all get dynamic IPs for use on your lapto $ ./easyrsa build-client-full client nopass # optional ``` -Leave off `nopass` if you want to password protect the config file keys when you set up a new client. +Leave off `nopass` if you want to password protect the config file keys when you set up a new client (PEM pass phrase). Create the server config file `/etc/openvpn/server.conf`: @@ -115,21 +118,15 @@ persist-key persist-tun ``` -Assign a static IP + chmod: - -``` -$ cd /etc/openvpn -$ sudo chown -R root:root easy-rsa/ -$ sudo mkdir ccd -$ sudo touch ccd/mediaserver -``` - -Replace `mediaserver` with whatever client name you used above. Edit it like so: +Assign a static IP: (Your home server will be `10.8.0.100`) ``` -ifconfig-push 10.8.0.100 255.255.255.0 +$ cd /etc/openvpn +$ mkdir ccd +$ echo "ifconfig-push 10.8.0.100 255.255.255.0" > mediaserver +$ echo "ifconfig-push 10.8.0.101 255.255.255.0" > anotherserver ``` Test your config by running: @@ -149,6 +146,12 @@ If you run `ip addr` in another terminal, you should see an entry like this: valid_lft forever preferred_lft forever ``` +Change back ownership: + +``` +$ sudo chown -R root:root /etc/openvpn +``` + ### systemd If it works fine, persist OpenVPN with systemd: @@ -201,7 +204,7 @@ Add this to the top of `/etc/ufw/before.rules`: -A POSTROUTING -d 10.8.0.100 -p tcp --dport 2222 -j SNAT --to-source 10.8.0.1 # Allow traffic from OpenVPN client to eth0 --A POSTROUTING -s 10.8.0.0/8 -o eth0 -j MASQUERADE +-A POSTROUTING -s 10.8.0.0/24 -o eth0 -j MASQUERADE COMMIT ```