On 21/01/2021 19:09, Ard Biesheuvel wrote: > On Thu, 21 Jan 2021 at 19:05, Eric Biggers <ebiggers@xxxxxxxxxx> wrote: >> >> On Thu, Jan 21, 2021 at 02:07:33PM +0100, Ard Biesheuvel wrote: >>> Salsa20 is not used anywhere in the kernel, is not suitable for disk >>> encryption, and widely considered to have been superseded by ChaCha20. >>> So let's remove it. >>> >>> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx> >>> --- >>> Documentation/admin-guide/device-mapper/dm-integrity.rst | 4 +- >>> crypto/Kconfig | 12 - >>> crypto/Makefile | 1 - >>> crypto/salsa20_generic.c | 212 ---- >>> crypto/tcrypt.c | 11 +- >>> crypto/testmgr.c | 6 - >>> crypto/testmgr.h | 1162 -------------------- >>> 7 files changed, 3 insertions(+), 1405 deletions(-) >>> >>> diff --git a/Documentation/admin-guide/device-mapper/dm-integrity.rst b/Documentation/admin-guide/device-mapper/dm-integrity.rst >>> index 4e6f504474ac..d56112e2e354 100644 >>> --- a/Documentation/admin-guide/device-mapper/dm-integrity.rst >>> +++ b/Documentation/admin-guide/device-mapper/dm-integrity.rst >>> @@ -143,8 +143,8 @@ recalculate >>> journal_crypt:algorithm(:key) (the key is optional) >>> Encrypt the journal using given algorithm to make sure that the >>> attacker can't read the journal. You can use a block cipher here >>> - (such as "cbc(aes)") or a stream cipher (for example "chacha20", >>> - "salsa20" or "ctr(aes)"). >>> + (such as "cbc(aes)") or a stream cipher (for example "chacha20" >>> + or "ctr(aes)"). >> >> You should check with the dm-integrity maintainers how likely it is that people >> are using salsa20 with dm-integrity. It's possible that people are using it, >> especially since the documentation says that dm-integrity can use a stream >> cipher and specifically gives salsa20 as an example. >> > > Good point - cc'ed them now. I would say - just remove it. I do not see any users, we do not even test this combination in userspace testsuite. It is just an example in doc. >From my POV these stream crypto ciphers should be never used there (but cc to Mikulas, it was his patch :-) Milan
