Exemplo n.º 1
0
def main():
    secret = trapdoor.loadtrapdoor()
    if len(sys.argv) < 5 or (sys.argv[-2] not in ("-out", "--out")):
        print("usage: python3 encrypt.py <realtext>",
              "<faketext0> [<faketext1> ...] -out <outfile>")
        return

    faketextfns = sys.argv[2:-2]
    realtextfn = sys.argv[1]
    outfn = sys.argv[-1]

    print("plaintext:", realtextfn)
    print("decoy texts:", faketextfns)
    print("encrypted output:", outfn)

    inbits = streamofbits.bits(realtextfn, infinitepad=True)
    fakestreams = [streamofbits.bits(fn, infinitepad=True)
                   for fn in faketextfns]
    realkey = []
    fakekeys = []

    for fn in faketextfns:
        fakekeys.append([])
    totalbits = 8 * streamofbits.maxfilesize([realtextfn] + faketextfns)

    with open(outfn, "wb") as outfile:
        for bitnum in range(totalbits):
            inbit = next(inbits)
            enc = encode(inbit, secret)
            asbytes = streamofbits.bits_to_bytes(enc)
            outfile.write(bytes(asbytes))
            realkey.append(enc[0] ^ inbit)

            for fakestream,fakekey in zip(fakestreams,fakekeys):
                fakebit = next(fakestream)
                fakekey.append(enc[0] ^ fakebit)

    with open("realkey", "wb") as outfile:
        asbytes = streamofbits.bits_to_bytes(realkey)
        outfile.write(bytes(asbytes))

    for i,fakekey in enumerate(fakekeys):
        with open("fakekey{0}".format(i), "wb") as outfile:
            asbytes = streamofbits.bits_to_bytes(fakekey)
            outfile.write(bytes(asbytes))
Exemplo n.º 2
0
def main():
    if len(sys.argv) != 3:
        print("usage: python3 decryptwithkey.py <infile> <keyfile>")
        return

    inbits = streamofbits.bits(sys.argv[1])
    inkeybits = streamofbits.bits(sys.argv[2])

    cipherbits = list(inbits)
    keybits = list(inkeybits)

    plainbits = []

    encodinglength = constants.ELEMENT_LENGTH * constants.ELEMENTS_PER_BIT
    encodeds = streamofbits.n_at_a_time(cipherbits, encodinglength)
    for encoded,keybit in zip(encodeds, keybits):
        nextbit = encoded[0] ^ keybit
        plainbits.append(nextbit)
    print(bytes.decode(bytes(streamofbits.bits_to_bytes(plainbits))), end="")
Exemplo n.º 3
0
def main():
    secret = trapdoor.loadtrapdoor()
    if len(sys.argv) != 2:
        print("usage: python3 decrypt.py <infile>")
        return

    inbits = streamofbits.bits(sys.argv[1])
    cipherbits = list(inbits)
    plainbits = []
    for encoded in streamofbits.n_at_a_time(cipherbits,
                                constants.ELEMENT_LENGTH *
                                constants.ELEMENTS_PER_BIT):
        numS = countSs(encoded, secret)
        plainbits.append(numS % 2)

    print(bytes.decode(bytes(streamofbits.bits_to_bytes(plainbits))), end="")