Clarify documentation

LICENSE.md

@@ -0,0 +1,165 @@
+                   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
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+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
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README.md

@@ -21,19 +21,19 @@ Bob needs to travel to a country with a legislation that requires individuals to
 enforcement. That being the case, Bob wants to keep his private data out of their eyes, to protect his privacy. He
 creates two keys, one intended to be kept secret, the other intended to be sacrificed.
 
-Bob constructs an innocuous message M1 (intended to be revealed to the police in case of discovery) and another one,
-containing the personal data M2 he does not want anyone to know about.
+Bob constructs an innocuous message M1 (intended to be revealed to the secret police in case of discovery) and another
+one, containing the personal data M2 he does not want anyone to know about.
 
 He constructs a cipher-text C out of both messages, M1 and M2, stores it on his device.
 
 Bob travels to the country, passes the border control and later uses his key to decrypt M2 (and possibly M1, in order
-to read the fake message, too).
+to read the decoy message, too).
 
-The police arrest Bob at the border control and finds the encrypted blob on his device, becomes suspicious and forces
-Bob to decrypt the message.
+The secret police arrest Bob and finds the encrypted blob on his device, becomes suspicious and forces Bob to decrypt
+the message.
 
-Bob uses the sacrificial key and reveals the innocuous message M1 to the police. Since it is impossible for the police
-to know for sure that there might be other messages contained in C, they might assume that there are no other messages.
+Bob uses the sacrificial key and reveals the innocuous message M1 to the secret police. Since it is impossible for them
+to know for sure if there are other messages contained in C, they might assume that there are no other messages.
 
 ## Goals
 
@@ -48,6 +48,10 @@ Bear in mind this project was created with the _requirements_ below in mind, it
 * Portable, without any system dependencies (statically linked binaries).
 * Does not require kernel or userspace filesystems.
 
+## Algorithms
+
+Covert uses *scrypt* to hash the passphrases and *AES256-GCM* to encrypt the partitions.
+
 ## Documentation
 
 All the documentation lives in the `docs` folder.

cmd/terminal.go

@@ -0,0 +1 @@
+package main

docs/approach.md

@@ -6,27 +6,29 @@ Coverts encrypted volumes are composed of one or more of the following parts con
 - Decoy partition (DP): Innocuous file(s), as decoys.
 - Garbage Partition (RP): Key is thrown away during volume creation.
 
-Decoy and secret partitions are optional, you can use this tool to create a single AES-256 partition.
+Note: Decoy and secret partitions are optional, but you should probably specify them. 
+Note: A volume is composed of at least 3 partitions.
 
-You could, for example, create a new volume composed of 5 parts:
+You could, for example, create a new volume composed of 3 partitions:
 
-| _DP_ | *SP* | GP | _DP_ | GP |
+| _Decoy_ | *Secret* | Garbage |
 
-If you were put in a position where you were forced to give away the keys, you could provide one, or two, of the
-insignificant partitions. Keeping to Secret partition's key to yourself and pretending you do not have the key to
-the other volumes, as they are garbage.
+If you were put in a position where you were forced to give away the keys, you could provide the key to the 
+insignificant partition. Keeping the Secret partition's key to yourself and pretending you do not have the
+key to the other volumes, and that they are all garbage.
+
+You could go further by adding, for example, two or more decoy partitions.
+
+| _Decoy_ | *Secret* | _Decoy_ | Garbage |
 
 ## Considerations
 
-- The minimum number of partitions is 3: 1 SP, 1 IP and 1 RP, there are no maximums.
-- All the partitions are always of the same size, and a total volume size is always `vsize = biggest_file * number_partition`.
-- Partition location are random.
-- Covert only supports 1 file per partition currently.
-- The performance of the implementation could be optimised in a few areas.
+- All the partitions are always of the same size, and the volume size is `vsize = number_partition * (biggest_file + AES overhead)`.
+- Partition location are randomised during the creation of the volume.
+- Covert currently only supports 1 file per partition (you could provide an ISO-9660 or a DMG to work around this, though).
+- The current implementation can be slow with large amounts of data
 
 ## Flows
 
 When a user enters a key, Covert will iterate over all the partitions until it find one for which the key matches. If
-no matching partition are found the decryption will fail.
-
-## Choice of algorithms
+no matching partition are found the decryption will fail.

internal/msg/info.go

@@ -0,0 +1 @@
+package msg