On 20/06/2019 15:52, Ard Biesheuvel wrote: >>>> Does this include configurations that combine authenc with essiv? >>> >>> Hm, seems that we are missing these in luks2-integrity-test. I'll add them there. >>> >>> I also used this older test >>> https://gitlab.com/omos/dm-crypt-test-scripts/blob/master/root/test_dmintegrity.sh >>> >>> (just aes-gcm-random need to be commented out, we never supported this format, it was >>> written for some devel version) >>> >>> But seems ESSIV is there tested only without AEAD composition... >>> >>> So yes, this AEAD part need more testing. >> >> And unfortunately it does not work - it returns EIO on sectors where it should not be data corruption. >> >> I added few lines with length-preserving mode with ESSIV + AEAD, please could you run luks2-integrity-test >> in cryptsetup upstream? >> >> This patch adds the tests: >> https://gitlab.com/cryptsetup/cryptsetup/commit/4c74ff5e5ae328cb61b44bf99f98d08ffee3366a >> >> It is ok on mainline kernel, fails with the patchset: >> >> # ./luks2-integrity-test >> [aes-cbc-essiv:sha256:hmac-sha256:128:512][FORMAT][ACTIVATE]sha256sum: /dev/mapper/dmi_test: Input/output error >> [FAIL] >> Expecting ee501705a084cd0ab6f4a28014bcf62b8bfa3434de00b82743c50b3abf06232c got . >> >> FAILED backtrace: >> 77 ./luks2-integrity-test >> 112 intformat ./luks2-integrity-test >> 127 main ./luks2-integrity-test >> > > OK, I will investigate. > > I did my testing in a VM using a volume that was created using a > distro kernel, and mounted and used it using a kernel with these > changes applied. > > Likewise, if I take a working key.img and mode-test.img, i can mount > it and use it on the system running these patches. > > I noticed that this test uses algif_skcipher not algif_aead when it > formats the volume, and so I wonder if the way userland creates the > image is affected by this? Not sure if I understand the question, but I do not think userspace even touch data area here (except direct-io wiping after the format, but it does not read it back). It only encrypts keyslots - and here we cannot use AEAD (in fact it is already authenticated by a LUKS digest). So if the data area uses AEAD (or composition of length-preserving mode and some authentication tag like HMAC), we fallback to non-AEAD for keyslot encryption. In short, to test it, you need to activate device (that works ok with your patches) and *access* the data, testing LUKS format and just keyslot access will never use AEAD. So init the data by direct-io writes, and try to read them back (with dd). For testing data on dm-integrity (or dm-crypt with AEAD encryption stacked oved dm-integrity) I used small utility, maybe it could be useful https://github.com/mbroz/dm_int_tools Milan
