• Ard Biesheuvel's avatar
    crypto: omap-aes - permit asynchronous skcipher as fallback · 6a99d7a2
    Ard Biesheuvel authored
    Even though the omap-aes driver implements asynchronous versions of
    ecb(aes), cbc(aes) and ctr(aes), the fallbacks it allocates are required
    to be synchronous. Given that SIMD based software implementations are
    usually asynchronous as well, even though they rarely complete
    asynchronously (this typically only happens in cases where the request was
    made from softirq context, while SIMD was already in use in the task
    context that it interrupted), these implementations are disregarded, and
    either the generic C version or another table based version implemented in
    assembler is selected instead.
    
    Since falling back to synchronous AES is not only a performance issue, but
    potentially a security issue as well (due to the fact that table based AES
    is not time invariant), let's fix this, by allocating an ordinary skcipher
    as the fallback, and invoke it with the completion routine that was given
    to the outer request.
    Signed-off-by: default avatarArd Biesheuvel <ardb@kernel.org>
    Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
    6a99d7a2
omap-aes.h 5.99 KB