know when they are online. Let's solve this problem once-and-for-all
in a decentralised, sustainable and future proof way.
-## Here come's the real IPv6 friend
+## Here comes the real IPv6 friend
+
+Instead of using a single system or server, we use IPv6 to connect to
+our friends directly. Because each of our friends is reachable by IPv6
+if they are online (otherwise they would not be a real IPv6 friend),
+we can easily verify if they are online. To find out who is online,
+just connect to their computer!
+
+## How it works
+
+It's a bit geeky, but it works actually rather simple.
+To become a real IPv6 friend, you need to do the following things:
+
+- Generate a GPG key with a comment named **RIF** following the URL of
+ your computer (f.i. **RIF https://nico.ungleich.cloud**)
+- Ensure that the URL points to the IPv6 address of your computer
+- Setup a webserver on your computer
+- Export your key and all real IPv6 friend keys to your webserver as
+ "rifkeys.txt
+- For each of your friends, check whether they are online
+- Import the friends of your friends and check whether they are
+ online, too!
+- Send friend requests (like other platforms!)
+
+### Example: Generating a key with the right comment
+
+In this example I choose to create an ECC based key that requires the
+export option in gpg:
+
+```
+[1:24] line:~% gpg --expert --full-gen-key
+gpg (GnuPG) 2.2.12; Copyright (C) 2018 Free Software Foundation, Inc.
+This is free software: you are free to change and redistribute it.
+There is NO WARRANTY, to the extent permitted by law.
+
+Please select what kind of key you want:
+ (1) RSA and RSA (default)
+ (2) DSA and Elgamal
+ (3) DSA (sign only)
+ (4) RSA (sign only)
+ (7) DSA (set your own capabilities)
+ (8) RSA (set your own capabilities)
+ (9) ECC and ECC
+ (10) ECC (sign only)
+ (11) ECC (set your own capabilities)
+ (13) Existing key
+Your selection? 9
+Please select which elliptic curve you want:
+ (1) Curve 25519
+ (3) NIST P-256
+ (4) NIST P-384
+ (5) NIST P-521
+ (6) Brainpool P-256
+ (7) Brainpool P-384
+ (8) Brainpool P-512
+ (9) secp256k1
+Your selection? 1
+Please specify how long the key should be valid.
+ 0 = key does not expire
+ <n> = key expires in n days
+ <n>w = key expires in n weeks
+ <n>m = key expires in n months
+ <n>y = key expires in n years
+Key is valid for? (0) 0
+Key does not expire at all
+Is this correct? (y/N) y
+
+GnuPG needs to construct a user ID to identify your key.
+
+Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? c
+Comment: RIF https://nico.ungleich.cloud
+You selected this USER-ID:
+ "Nico Schottelius (RIF https://nico.ungleich.cloud) <ipv6@nico.ungleich.cloud>"
+
+Change (N)ame, (C)omment, (E)mail or (O)kay/(Q)uit? o
+We need to generate a lot of random bytes. It is a good idea to perform
+some other action (type on the keyboard, move the mouse, utilize the
+disks) during the prime generation; this gives the random number
+generator a better chance to gain enough entropy.
+We need to generate a lot of random bytes. It is a good idea to perform
+some other action (type on the keyboard, move the mouse, utilize the
+disks) during the prime generation; this gives the random number
+generator a better chance to gain enough entropy.
+gpg: key 27541E11E73F288D marked as ultimately trusted
+gpg: directory '/home/nico/.gnupg/openpgp-revocs.d' created
+gpg: revocation certificate stored as '/home/nico/.gnupg/openpgp-revocs.d/B982A8BABC030C66DEF5984527541E11E73F288D.rev'
+public and secret key created and signed.
+
+pub ed25519 2019-09-09 [SC]
+ B982A8BABC030C66DEF5984527541E11E73F288D
+uid Nico Schottelius (RIF https://nico.ungleich.cloud) <ipv6@nico.ungleich.cloud>
+sub cv25519 2019-09-09 [E]
+
+
+```
+
+### Example: Setting up a webserver
+
+On a Debian/Devuan based distro:
+
+```
+apt install nginx
+sudo chown $(whoami) /var/www/html
+```
+
+
+### Exporting all keys
+
+To make yourself accessible and expose who your real IPv6 friends are.
+
+```
+gpg -a --export RIF > /var/www/html/rifkeys
+```
+
+### Example: List your friends
+
+You can use the included rif-listfriends.sh or directly gpg:
+
+```
+[1:40] line:~% gpg --list-keys --with-colons | grep RIF | awk -F: '{ print $10 }' | sed 's/\\x3a/:/'
+Nico Schottelius (RIF https://nico.ungleich.cloud) <ipv6@nico.ungleich.cloud>
+Nico Schottelius (myself) (RIF https://nico2.ungleich.cloud) <nico@nico.ungleich.cloud>
+```
+
+
+### Example: Checking which friends are online
+
+Use the included rif-checkfriends.sh script or iterate yourself over
+above output.
+
+```
+[1:54] line:realipv6friend% sh rif-checkfriends.sh
+Checking Nico Schottelius on https://nico.ungleich.cloud ...
+Nico Schottelius is online
+Checking Nico Schottelius (myself) on https://nico2.ungleich.cloud ...
+Nico Schottelius (myself) is offline
+[1:54] line:realipv6friend%
+
+```
+
+### Example: Importing friends of my friend
+
+Importing friends of a friend is as simple as importing all the
+exported keys! We import friends directly from the URL of a friend:
+
+```
+curl -6 -s https://nico.ungleich.cloud/rifkeys | gpg --import
+```
+
+You can also use the included rif-importfriends.sh.
+
+
+### Example: Updating your friends
+
+Now that you have imported the friends of your friends, they have
+automatically also become your friends!
+
+Obviously, you will want to check whether you even want to sign some
+of the friends (keys) that you downloaded, but clearly you want to
+show off with the biggest amount of friends (that's what is most
+important anyway, isn't it?).
+
+In any case, to update your friend list, simply repeat the command you
+ran above already in the beginning:
+
+```
+gpg -a --export RIF > /var/www/html/rifkeys
+```
+
+Or use the included `rif-exportfriends.sh`
+
+### Example: Importing friends of all friends and exporting them
+
+From time to time you might want to checkup on which friends gained
+new friends and add them to your friend list. This is as easy as
+iterating over all your friends and importing their friends into your
+friends list. And because you are a good friend, you might want to
+export all friends again.
+
+To make things easy, the included a script `rif-friendimportexport.sh`
+automates this process.
+
+
+### Example: Sending a message to a friend
+
+You can probably just use your mail program for that - and you might
+even be able to send it IPv6 only!
+
+### Example: Invite a friend
+
+Live is not great without friends! Let's invite a friend! This is as
+easy is this:
+
+```
+printf 'Hello yournamehere!\n I am looking for real IPv6 friends.\n You find my friends on https://nico.ungleich.cloud/rifkeys.\nHow real IPv6 friends find each other is explained on https://code.ungleich.ch/nico/rif.\n Looking forward to befriend you!' | mail -s "friend request" ipv6@your.friend.example.com
+```
+
+And obviously this is waaaaaaaaay to long to type. That's why
+`rif-invitefriends.sh` puts this nicely into a script.
+
+Attention: this requires a working mail setup on your computer
+(i.e. outgoing emails sending by `mail` works).
+
+## Finding friends
+
+As real IPv6 friends are decentralised, there is no central registry
+of friends. Just startup the webserver on your machine, export your
+key(s) and ping your friend.
+
+With every friend that is added to your network, the reach grows in
+the chain of all friends of every friend!
+
+So just start in your small cycle and forward your friend URL to your
+friends!
+
+
+## About
+
+Real IPv6 friend is a project launched by Nico Schottelius on 2019-09-10.
+If you want to become my friend, my friend URL is https://nico.ungleich.cloud.
projects / user / henk / code / shell / rif.git / blobdiff