encryption

TL;DR: Inserting a file into Freenet using the key KSK@<password> creates an invisible, password protected file which is available over Freenet.

Often you want to exchange some content only with people who know a given password and make it accessible to everyone in your little group but invisible to the outside world.

Until yesterday I thought that problem slightly complex, because everyone in your group needs a given encryption program, and you need a way to share the file without exposing the fact that you are sharing it.

Then I learned two handy facts about Freenet:

• Content is invisible to all but those with the key
  <ArneBab> evanbd: If I insert a tiny file without telling anyone the key, can they get the content in some way?
  <evanbd> ArneBab: No.

• You generate a key from a password by using a KSK-key
  <toad_> dogon: KSK@<any string of text> -> generate an SSK private key from the hash of the text
  <toad_> dogon: if you know the string, you can both insert and retrieve it

In other words:

Just inserting a file into Freenet using the key KSK@<password> creates an invisible, password protected file which is shared over Freenet.