crypto: algapi - use common mechanism for inheriting flags
authorEric Biggers <ebiggers@google.com>
Fri, 10 Jul 2020 06:20:38 +0000 (23:20 -0700)
committerHerbert Xu <herbert@gondor.apana.org.au>
Thu, 16 Jul 2020 11:49:08 +0000 (21:49 +1000)
commit7bcb2c99f8ed032cfb3f5596b4dccac6b1f501df
tree7d8e914c0368036db8f1d99a923387833546330a
parent4688111e78ed432b19c3cd6de545c83c47dc28b3
crypto: algapi - use common mechanism for inheriting flags

The flag CRYPTO_ALG_ASYNC is "inherited" in the sense that when a
template is instantiated, the template will have CRYPTO_ALG_ASYNC set if
any of the algorithms it uses has CRYPTO_ALG_ASYNC set.

We'd like to add a second flag (CRYPTO_ALG_ALLOCATES_MEMORY) that gets
"inherited" in the same way.  This is difficult because the handling of
CRYPTO_ALG_ASYNC is hardcoded everywhere.  Address this by:

  - Add CRYPTO_ALG_INHERITED_FLAGS, which contains the set of flags that
    have these inheritance semantics.

  - Add crypto_algt_inherited_mask(), for use by template ->create()
    methods.  It returns any of these flags that the user asked to be
    unset and thus must be passed in the 'mask' to crypto_grab_*().

  - Also modify crypto_check_attr_type() to handle computing the 'mask'
    so that most templates can just use this.

  - Make crypto_grab_*() propagate these flags to the template instance
    being created so that templates don't have to do this themselves.

Make crypto/simd.c propagate these flags too, since it "wraps" another
algorithm, similar to a template.

Based on a patch by Mikulas Patocka <mpatocka@redhat.com>
(https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com).

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
23 files changed:
crypto/adiantum.c
crypto/algapi.c
crypto/authenc.c
crypto/authencesn.c
crypto/ccm.c
crypto/chacha20poly1305.c
crypto/cmac.c
crypto/cryptd.c
crypto/ctr.c
crypto/cts.c
crypto/essiv.c
crypto/gcm.c
crypto/geniv.c
crypto/hmac.c
crypto/lrw.c
crypto/pcrypt.c
crypto/rsa-pkcs1pad.c
crypto/simd.c
crypto/skcipher.c
crypto/vmac.c
crypto/xcbc.c
crypto/xts.c
include/crypto/algapi.h