On Mon, May 06, 2019 at 08:57:22AM -0700, Eric Biggers wrote: > On Fri, Apr 26, 2019 at 01:41:46PM -0700, Eric Biggers wrote: > > Hello, > > > > This series adds xfstests which verify that encrypted contents and > > filenames on ext4 and f2fs are actually correct, i.e. that the > > encryption uses the correct algorithms, keys, IVs, and padding amounts. > > The new tests work by creating encrypted files, unmounting the > > filesystem, reading the ciphertext from disk using dd and debugfs or > > dump.f2fs, and then comparing it against ciphertext computed > > independently by a new test program that implements the same algorithms. > > > > These tests are important because: > > > > - The whole point of file encryption is that the files are actually > > encrypted correctly on-disk. Except for generic/399, current xfstests > > only tests the filesystem semantics, not the actual encryption. > > generic/399 only tests for incompressibility of encrypted file > > contents using one particular encryption setting, which isn't much. > > > > - fscrypt now supports 4 main combinations of encryption settings, > > rather than 1 as it did originally. This may be doubled to 8 soon > > (https://patchwork.kernel.org/patch/10908153/). We should test all > > settings. And without tests, even if the initial implementation is > > correct, breakage in one specific setting could go undetected. > > > > - Though Linux's crypto API has self-tests, these only test the > > algorithms themselves, not how they are used, e.g. by fscrypt. > > > > Patch 1 is a cleanup patch. Patches 2-4 add the common helpers for > > ciphertext verification tests. Patches 5-7 add the actual tests. > > > > These tests require e2fsprogs and f2fs-tools patches I recently sent out > > to fix printing encrypted filenames. So, this series might not be > > suitable for merging into mainline xfstests until those patches are > > applied. Regardless, comments are appreciated. The needed patches are: > > > > debugfs: avoid ambiguity when printing filenames (https://marc.info/?l=linux-ext4&m=155596495624232&w=2) > > f2fs-tools: improve filename printing (https://sourceforge.net/p/linux-f2fs/mailman/message/36648641/) > > > > This series can also be retrieved from git at > > https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/xfstests-dev.git > > branch "ciphertext-verification". > > > > I also have patches on top of this series which verify the ciphertext > > produced from v2 encryption policies, which are proposed by my kernel > > patch series "fscrypt: key management improvements" > > (https://patchwork.kernel.org/cover/10908107/). v2 encryption policies > > will use a different key derivation function, and thus their ciphertext > > will be different. These additional patches can be found at branch > > "fscrypt-key-mgmt-improvements" of my git repo above. But I've arranged > > things such that this shorter series can potentially be applied earlier, > > to test what's in the kernel now. > > > > Eric Biggers (7): > > common/encrypt: introduce helpers for set_encpolicy and get_encpolicy > > fscrypt-crypt-util: add utility for reproducing fscrypt encrypted data > > common/encrypt: support requiring other encryption settings > > common/encrypt: add helper for ciphertext verification tests > > generic: verify ciphertext of v1 encryption policies with AES-256 > > generic: verify ciphertext of v1 encryption policies with AES-128 > > generic: verify ciphertext of v1 encryption policies with Adiantum > > > > .gitignore | 1 + > > common/encrypt | 482 ++++++++++- > > src/Makefile | 3 +- > > src/fscrypt-crypt-util.c | 1645 ++++++++++++++++++++++++++++++++++++++ > > tests/ext4/024 | 3 +- > > tests/generic/395 | 28 +- > > tests/generic/395.out | 2 +- > > tests/generic/396 | 15 +- > > tests/generic/397 | 3 +- > > tests/generic/398 | 5 +- > > tests/generic/399 | 3 +- > > tests/generic/419 | 3 +- > > tests/generic/421 | 3 +- > > tests/generic/429 | 3 +- > > tests/generic/435 | 3 +- > > tests/generic/440 | 5 +- > > tests/generic/700 | 41 + > > tests/generic/700.out | 5 + > > tests/generic/701 | 41 + > > tests/generic/701.out | 5 + > > tests/generic/702 | 43 + > > tests/generic/702.out | 10 + > > tests/generic/group | 3 + > > 23 files changed, 2308 insertions(+), 47 deletions(-) > > create mode 100644 src/fscrypt-crypt-util.c > > create mode 100755 tests/generic/700 > > create mode 100644 tests/generic/700.out > > create mode 100755 tests/generic/701 > > create mode 100644 tests/generic/701.out > > create mode 100755 tests/generic/702 > > create mode 100644 tests/generic/702.out > > > > -- > > 2.21.0.593.g511ec345e18-goog > > > > Any comments on this? Sorry for the late review, I went through the patches and they look fine to me over all from fstests perspective, I replied a few minor issues to individual patches. It'd be great if ext4 and/or f2fs folks could help review the tests as well. Thanks, Eryu > > FYI, the e2fsprogs patch that these tests need was applied. > > I'm still waiting for the f2fs-tools patch. > > - Eric
