John starr rocks!

doc/fileformat.md

@@ -1,4 +1,46 @@
 
+### public contract
+
+A public contract is the information a user publish to allow anybody to send 
+him encrypted files.  Of course the public contract contains the user
+public key but it contains much more.
+
+The contract itself does not need to be sign.  The signature is level of
+complexity above the public contract
+
+
+~~~
+---
+#  example of a  contract
+
+name: john dear
+
+organizarion: JohnDeer corporation
+
+email: johndear@johndeer.co
+
+url: "the url where to fiofbnd an exact copy of the contract"
+
+root_url: "the url where to find the most up to date version of the contract"
+
+accepted_hashs:
+	- sha512
+
+accepted_block_cypher:
+	- aes
+
+accepted_modes:
+	- ofb
+
+signatures_required: yes
+
+rsa_public_keys:
+	-
+		n: "hexadecimal n"
+		e: 3424
+~~~
+
+
 ### public key
 Note that any private key are a public key.