[PATCH v2 0/6] Support Argon2 KDF in LUKS2

[Patrick Steinhardt]

Hi,

this is the second version of my patchset to add support for Argon2
encryption keys for LUKS2.

The most important change is that I've now verbosely imported the argon2
code from the official reference implementation instead of from the
cryptsetup project. The diff between both isn't that big in the end, and
including from crypsetup's upstream seems a bit cleaner to me. There
were several transformations required to use GRUB's types and functions
as well as stripping of unused stuff, which I've now documented the dev
manual. This also fixes my previously mistaken license headers.

One thing I'm not sure about here is whether it's fine to declare the
argon2 mod's license as GPLv3. The code is licensed under CC0/Apache
2.0, where the latter is compatible with GPLv3. But I don't know whether
it's legit to just say "Yeah, this mod is a GPLv3 one".

I didn't address the comment made by Leif yet with regards to grabbing
memory. I ain't got much of a clue of GRUB's memory subsystem, so I'd
gladly accept help there. Otherwise I'll have to dig a bit deeper.

The range diff compared to the previous version of this patch set is
attached to this mail.

Patrick


Patrick Steinhardt (6):
  efi: Allocate half of available memory by default
  types.h: add UINT-related macros needed for Argon2
  argon2: Import Argon2 from cryptsetup
  luks2: Add missing newline to debug message
  luks2: Discern Argon2i and Argon2id
  luks2: Support key derival via Argon2

 Makefile.util.def                             |   6 +-
 docs/grub-dev.texi                            |  64 +++
 grub-core/Makefile.core.def                   |  10 +-
 grub-core/disk/luks2.c                        |  28 +-
 grub-core/kern/efi/mm.c                       |   4 +-
 grub-core/lib/argon2/argon2.c                 | 232 ++++++++
 grub-core/lib/argon2/argon2.h                 | 264 +++++++++
 grub-core/lib/argon2/blake2/blake2-impl.h     | 151 +++++
 grub-core/lib/argon2/blake2/blake2.h          |  89 +++
 grub-core/lib/argon2/blake2/blake2b.c         | 388 +++++++++++++
 .../lib/argon2/blake2/blamka-round-ref.h      |  56 ++
 grub-core/lib/argon2/core.c                   | 525 ++++++++++++++++++
 grub-core/lib/argon2/core.h                   | 228 ++++++++
 grub-core/lib/argon2/ref.c                    | 190 +++++++
 include/grub/types.h                          |   8 +
 15 files changed, 2231 insertions(+), 12 deletions(-)
 create mode 100644 grub-core/lib/argon2/argon2.c
 create mode 100644 grub-core/lib/argon2/argon2.h
 create mode 100644 grub-core/lib/argon2/blake2/blake2-impl.h
 create mode 100644 grub-core/lib/argon2/blake2/blake2.h
 create mode 100644 grub-core/lib/argon2/blake2/blake2b.c
 create mode 100644 grub-core/lib/argon2/blake2/blamka-round-ref.h
 create mode 100644 grub-core/lib/argon2/core.c
 create mode 100644 grub-core/lib/argon2/core.h
 create mode 100644 grub-core/lib/argon2/ref.c

Range-diff against v1:
1:  53cdfdc27 = 1:  15bdf830e efi: Allocate half of available memory by default
2:  c55946ca5 < -:  --------- argon2: Import Argon2 from cryptsetup
-:  --------- > 2:  e81db7d95 types.h: add UINT-related macros needed for Argon2
-:  --------- > 3:  50aff9670 argon2: Import Argon2 from cryptsetup
3:  c17cd2197 ! 4:  af3f85665 disk: luks2: Add missing newline to debug message
    @@ Metadata
     Author: Patrick Steinhardt <address@hidden>
     
      ## Commit message ##
    -    disk: luks2: Add missing newline to debug message
    +    luks2: Add missing newline to debug message
     
         The debug message printed when decryption with a keyslot fails is
         missing its trailing newline. Add it to avoid mangling it with
         subsequent output.
     
         Signed-off-by: Patrick Steinhardt <address@hidden>
    +    Reviewed-by: Daniel Kiper <address@hidden>
     
      ## grub-core/disk/luks2.c ##
     @@ grub-core/disk/luks2.c: luks2_recover_key (grub_disk_t disk,
4:  390728cea ! 5:  89abe827b disk: luks2: Discern Argon2i and Argon2id
    @@ Metadata
     Author: Patrick Steinhardt <address@hidden>
     
      ## Commit message ##
    -    disk: luks2: Discern Argon2i and Argon2id
    +    luks2: Discern Argon2i and Argon2id
     
         While GRUB is already able to parse both Argon2i and Argon2id 
parameters
         from the LUKS2 header, it doesn't discern both types. This commit
5:  ec4389627 ! 6:  70a354e0b disk: luks2: Support key derival via Argon2
    @@ Metadata
     Author: Patrick Steinhardt <address@hidden>
     
      ## Commit message ##
    -    disk: luks2: Support key derival via Argon2
    +    luks2: Support key derival via Argon2
     
         One addition with LUKS2 was support of the key derival function Argon2
         in addition to the previously supported PBKDF2 algortihm. In order to
    @@ Makefile.util.def: library = {
        common = grub-core/kern/partition.c;
        common = grub-core/lib/crypto.c;
     +  common = grub-core/lib/argon2/argon2.c;
    ++  common = grub-core/lib/argon2/core.c;
    ++  common = grub-core/lib/argon2/ref.c;
     +  common = grub-core/lib/argon2/blake2/blake2b.c;
        common = grub-core/lib/json/json.c;
        common = grub-core/disk/luks.c;
    @@ grub-core/disk/luks2.c: luks2_decrypt_key (grub_uint8_t *out_key,
            case LUKS2_KDF_TYPE_ARGON2ID:
     -  ret = grub_error (GRUB_ERR_BAD_ARGUMENT, "Argon2 not supported");
     -  goto err;
    -+  ret = grub_crypto_argon2 (passphrase, passphraselen, salt, saltlen,
    -+                            k->kdf.u.argon2.time, k->kdf.u.argon2.memory, 
k->kdf.u.argon2.cpus,
    -+                            k->kdf.type == LUKS2_KDF_TYPE_ARGON2I ? 
GRUB_ARGON2_I : GRUB_ARGON2_ID,
    -+                            GRUB_ARGON2_VERSION_NUMBER,
    -+                            area_key, k->area.key_size);
    ++  ret = argon2_hash (k->kdf.u.argon2.time, k->kdf.u.argon2.memory, 
k->kdf.u.argon2.cpus,
    ++                     passphrase, passphraselen, salt, saltlen, area_key, 
k->area.key_size,
    ++                     k->kdf.type == LUKS2_KDF_TYPE_ARGON2I ? Argon2_i : 
Argon2_id,
    ++                     ARGON2_VERSION_NUMBER);
     +        if (ret)
     +    {
    -+      grub_dprintf ("luks2", "Argon2 failed: %s\n", grub_errmsg);
    ++      grub_dprintf ("luks2", "Argon2 failed: %s\n", argon2_error_message 
(ret));
     +      goto err;
     +    }
     +        break;
-- 
2.25.1