Re: [PATCH] crypto: remove md4 driver

[Denis Kenzior]

Hi Herbert,

On 10/13/23 05:39, Herbert Xu wrote:
> On Sun, Oct 08, 2023 at 05:01:39AM +0100, Dimitri John Ledkov wrote:
> > No internal users left and cryptographically insecure. Users should
> > upgrade to something else, e.g. sha256 blake3.
> >
> > Some drivers have their own full or partial md4 implementation without
> > using crypto/md4.
> >
> > Userspace code search indicates a few copies of hash_info.h
> > https://codesearch.debian.net/search?q=HASH_ALGO_MD4&literal=1 without
> > need for MD4.
> >
> > Preserve uapi hash algorithm indexes and array length, but rename the
> > MD4 enum.
> >
> > Signed-off-by: Dimitri John Ledkov <dimitri.ledkov@xxxxxxxxxxxxx>
> > ---
> >   crypto/Kconfig                 |   6 -
> >   crypto/Makefile                |   1 -
> >   crypto/hash_info.c             |   4 +-
> >   crypto/md4.c                   | 241 ---------------------------------
> >   crypto/tcrypt.c                |  12 --
> >   crypto/testmgr.c               |   6 -
> >   crypto/testmgr.h               |  42 ------
> >   include/uapi/linux/hash_info.h |   2 +-
> >   8 files changed, 3 insertions(+), 311 deletions(-)
> >   delete mode 100644 crypto/md4.c
>
> Patch applied.  Thanks.

Does this patch break userspace?

Here's a thread regarding MD4 the last time its removal was attempted:
https://lore.kernel.org/linux-crypto/20210818144617.110061-1-ardb@xxxxxxxxxx/

Please note that iwd does use MD4 hashes here:
https://git.kernel.org/pub/scm/libs/ell/ell.git/tree/ell/checksum.c#n63

https://git.kernel.org/pub/scm/network/wireless/iwd.git/tree/src/eap-mschapv2.c#n165

Regards,
-Denis