X-Git-Url: https://jxself.org/git/?a=blobdiff_plain;f=README;h=2d8dad9f3c7d72d442d710b4ee7fa12d92e37bf3;hb=335d0464d6ea90d5f30e6846e3142c287e0d582c;hp=f26c3461c4d2fb4cd106c0181519bd8f910f7dd1;hpb=efa545d64b910923248233618e774ca3b87efebb;p=tfcrypt.git

diff --git a/README b/README
index f26c346..2d8dad9 100644
--- a/README
+++ b/README
@@ -10,19 +10,19 @@ Blowfish and Twofish ciphers, which are in use still up to today.
 
 tfcrypt is actually a frontend for Threefish with (by default) XTS mode of operation.
 As a key it uses either password or keyfile, which is then hashed many times
-with Skein hash function. Default key length is 1280 bits (160 bytes).
+with Skein hash function.
 
 This program is incompatible with older, "tf1024" tfcrypt version. This version aims to
 provide a portable encryption tool to encrypt fixed media such as disks and archive files,
-as well as to provide decades long privacy for encrypted data. That's why it uses 1024 bit
-encryption and, unlike older version, extends key size to 1280 bits, eliminates tweak feature
-from Threefish and uses either XTS (by default) or OCB modes of operation instead,
-to encrypt fixed media in a secure undetectable way.
-
+as well as to provide decades long privacy for encrypted data.
 Supported modes of operation: CTR, ECB, CBC, XTS, OCB and arbitrary long keystream.
 OCB mode does not use Skein hash function to hash and verify message, instead, it does
 a single pass crypt and verify, thus, it is faster than other modes when both crypt and verify.
 
+Additionally, this version provides a way to virtually "extend" key size to 1280 bits,
+by enabling "fullkey" option or changing "do_full_key" default setting in tfcrypt_defs.h.
+In this mode, tweak is ignored, and filled with extended key material.
+
 THREEFISH NOTES
 
 Please note that this encryption software includes Threefish cipher, which is terribly
@@ -30,11 +30,7 @@ slow on 32 bit systems. This way, it cannot be efficiently used on pure 32 bit m
 
 Threefish contained here is stripped off of it's tweak property, thus, it is turned into a
 regular block cipher. To add tweakability, either XTS or OCB modes of operation are used.
-Default wide block size is 4096 bytes. Author strongly believes that Threefish _may_ be subject
-to related key attacks when used in a tweaked mode, so this property is easy to remove.
-Because tweak occupied another 192 bits of key material, these 192 bits are added to effective
-key length. Another key word is extracted from the sum of all the user key words, thus,
-another 64 bits. Total +256 additional bits of key = 1280 key bits.
+Default wide block size is 4096 bytes.
 
 SKEIN NOTES