ARCFOPA File Crypter documentation by EddyHawk
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What
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ARCFOPA is a file encrypter coded by EddyHawk (me).
It is part of PROTAGON File Crypter (PFC) series done by me.
ARCFOPA uses RC4+A cipher, MD4 & SHA-512 hash functions, and
 HMAC & PbKDF2 constructions, all (but Fixed RC4+) are taken from
 WE Pascal sources.

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What is RC4+A
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RC4+A (self-named) is RC4+ cipher modified as proposed by Banik & Jha [2014]:
-dumps the 1st 2 bytes of keystream
-changes the pad constant from $AA to $03
to resist distinguish attacks by Banik et al. [2013] & by Banik & Jha [2014].

Unbroken status: as 2015, 1 year

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What is RC4+
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RC4+ is a cipher designed by two Indian cryptographers: Subhamoy Maitra &
 Goutam Paul [2008].
It's a byte-oriented stream cipher having 0-2048 bit key & 0-2048 bit IV.
It's an independent upgrade of, or fixes to RC4 cipher designed by Ronald
 Rivest.

IP status:
Unbroken status: broken? in 5 years

Advantages over RC4:
 Supports IV
 Claimed to remove most of RC4 weaknesses

Disadvantages over RC4:
 KSA is  2.94x slower than RC4's KSA
 PRGA is 1.70x slower than RC4's PRGA

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What is WE Pascal source
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Wolfgang Ehrhardt (WE) creates a collection of crypt Pascal sources which is
freely available in Internet, supporting Borland Pascal 7, all flavors of
Borland Delphi, Free Pascal Compiler, & Virtual Pascal, in single source.

MD4 & Whirlpool hash function for ARCFOPA is taken by me from the same
collection [CRC_Hash 25 Aug 2014], then compiled under Virtual Pascal v2.1b279.

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Caution
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ARCFOPA status is experimental since RC4+A has:
-No public analysis yet.
-No test vector provided (can't check for implementation correctness).

End.