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    SubjectRe: [PATCH encrypted swsusp 1/3] core functionality
    folkert@vanheusden.com wrote:
    >>>The following patch adds the core functionality for the encrypted
    >>>suspend image.
    >>
    >>[Please inline patches, it makes it easier to comment on them.]

    Aiyeeh - good ole Mozilla tends to reformat things when inlining...

    >>You seem to reuse same key/iv for all the blocks. I'm no crypto
    >>expert, but I think that is seriously wrong... You probably should use
    >>block number as a IV or something like that.
    >
    >
    > Or use a feedback loop: xor your data with the outcome of the previous
    > round. And for the initial block use 0x00...00 for 'previous block'-
    > value.

    I'm already using cipher block chaining, look for CRYPTO_TFM_MODE_CBC in
    swsusp.c. You may want to have a look at cbc_process in crypto/cipher.c.
    Thus using the same key is ok. The only known drawback is a watermarking
    "attack" but this can only used to look for the existence of specially
    crafted files which are not stored on disk during software suspend.

    I should, however, use crypto_cipher_en/decrypt instead of
    crypto_cipher_en/decrypt_iv as I actually wanted to use the iv in the
    tfm I did set up with crypto_cipher_set_iv instead of the local copy.

    Going to fix that.
    --
    Andreas Steinmetz SPAMmers use robotrap@domdv.de
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