I'm quite busy now(I'm working for a RO2 emulator develope team)
So I'll post out the decryption code,in vb.net.
NF uses XOR to encrypt, the the encryption is quite the same als decryption you can try to make the encryption by yourself. here is the core cryption code:
Private key() As Byte = Helper.Helper.hextobytes("322C622E636D302C1556056B52B31D451064282BB3740F6B5F602929591F7615")
Private Sub Decrypt()
Dim ms As New IO.MemoryStream(buf)
Dim stream As New Stream.Stream(ms)
Dim v1 As New UInt32P, v2 As New UInt32P, v3 As New UInt32P
Dim buff As New ByteP(Convert.ToInt32(buf.Length - &HC))
Dim I As Integer
stream = stream >> v1 >> v2 >> v3 >> buff
buf = buff.Value
v2.Value = (v2.Value Xor &H390A4F16) - (v3.Value And &HFAFA) - (v1.Value And &HADAD)
Dim checksum As UInteger = 0
For I = 0 To buf.Length - 1
Dim tmp As UInteger
Try
tmp = checksum + ((buf(I) + 7) * (I + 3))
Catch ex As Exception
tmp = (CType(checksum, Long) - UInt32.MaxValue) + ((buf(I) + 7) * (I + 3)) - 1
Finally
checksum = tmp
End Try
Next
If v2.Value <> checksum Then
MsgBox("Checksum error", MsgBoxStyle.Critical)
End If
Dim v4(3) As Byte, v5(3) As Byte, swap(3) As Byte
ms = New IO.MemoryStream(v4)
stream = New Stream.Stream(ms)
stream = stream << v3
swap(2) = v4(0)
swap(3) = v4(1)
swap(1) = v4(2)
swap(0) = v4(3)
v4 = swap
ReDim swap(3)
ms = New IO.MemoryStream(v5)
stream = New Stream.Stream(ms)
stream = stream << v1
swap(3) = v5(0)
swap(2) = v5(1)
swap(0) = v5(2)
swap(1) = v5(3)
v5 = swap
I = 0
Dim J As Integer = 0
Do While I < buf.Length
buf(I) = buf(I) Xor v5(J Mod 4)
J += 1
I = I + J
Loop
For I = 0 To buf.Length - 1
buf(I) = buf(I) Xor v4(I Mod 4)
Next
Dim checksum2 As UInteger = 0
checksum = 0
For I = 0 To buf.Length - 1
Dim tmp As UInteger
Try
tmp = checksum + (buf(I) * (I + 1))
Catch ex As Exception
tmp = (CType(checksum, Long) - UInt32.MaxValue) + (buf(I) * (I + 1)) - 1
Finally
checksum = tmp
End Try
Next
For I = 0 To buf.Length - 1
Dim tmp As UInteger
Try
tmp = checksum2 + (buf(I) * ((I + &HD) ^ 2 Mod &H7B))
Catch ex As Exception
tmp = (CType(checksum2, Long) - UInt32.MaxValue) + (buf(I) * ((I + &HD) ^ 2 Mod &H7B)) - 1
Finally
checksum2 = tmp
End Try
Next
If v3.Value <> (checksum Xor &H390B6E5D) Then
MsgBox("Checksum error", MsgBoxStyle.Critical)
'Exit Sub
End If
If v1.Value <> (checksum2 Xor &H390AB2DD) Then
MsgBox("Checksum error", MsgBoxStyle.Critical)
'Exit Sub
End If
v4(0) = &HB2
v4(1) = &H39
v4(2) = &HDD
v4(3) = &HA
For I = 0 To buf.Length - 1
buf(I) = buf(I) Xor (v4(I Mod 4) + 7)
Next
Dim tmp64 As New Int64P, tmp16 As New UInt16P
ReDim v5(7)
ms = New IO.MemoryStream(v5)
stream = New Stream.Stream(ms)
J = buf.Length * 2
tmp64.Value = CType(J, Long) * &H55555556
stream = stream << tmp64
stream.Position = 4
stream = stream >> tmp16
tmp16.Value = tmp16.Value + (tmp16.Value >> &H1F)
buf(tmp16.Value) = buf(tmp16.Value) Xor &HB
buf(buf.Length \ 2) = buf(buf.Length \ 2) Xor &H6E
buf(0) = buf(0) Xor &H5D
Dim key2() As UShort
J = 0
Dim L As Integer
L = &HA + L
I = 0
While True
Dim K As Integer
K = J
key2 = GenerateKey(buf.Length + K + key(I Mod 32))
Dim tmm As Integer = 0
Dim ran As New Random(buf.Length + K + key(I Mod 32))
For J = K To K + key(I Mod 32) - 1
If J = buf.Length Then
OnFinished.Invoke(buf)
Exit Sub
End If
buf(J) = buf(J) Xor key(tmm Mod 32)
buf(J) = buf(J) Xor (key2(L Mod &H1000) Mod &H100)
L += &HD
tmm += 1
Next J
I += 1
pb.Value = (J / buf.Length) * 100
End While
End Sub
