Re: [PATCH v1 3/3] crypto: cavium - Register the CNN55XX supported crypto algorithms.

From: Stephan Müller
Date: Thu May 11 2017 - 08:22:39 EST


Am Donnerstag, 11. Mai 2017, 14:18:34 CEST schrieb srikanth jampala:

Hi srikanth,

> Hi Stephan,
>
> On Wednesday 10 May 2017 07:26 PM, Stephan Müller wrote:
> > Am Mittwoch, 10. Mai 2017, 15:06:40 CEST schrieb Srikanth Jampala:
> >
> > Hi Srikanth,
> >
> > In general: you are using the ablkcipher API. I think it is on its way out
> > and being replaced with skcipher.
> >
> > Maybe it makes sense to replace it here too. It could be as simple as s/
> > ablkcipher/skcipher/g
>
> Sure, I will do the changes accordingly.
> As per my understanding, I see the following changes,
> 1. CRYPTO_ALG_TYPE_ABLKCIPHER changed to CRYPTO_ALG_TYPE_SKCIPHER
> 2. nitrox_ablkcipher_foo() changed to nitrox_skcipher_foo()
>
> Please let me know, any other changes I have to consider?

What about all crypto_ablkcipher* function calls / structs? Also all
ablkcipher_request function calls/structs?
>
> >> +static inline int nitrox_ablkcipher_setkey(struct crypto_ablkcipher
> >> *cipher,
> >> + int aes_keylen, const u8 *key,
> >> + unsigned int keylen)
> >> +{
> >> + struct crypto_tfm *tfm = crypto_ablkcipher_tfm(cipher);
> >> + struct nitrox_crypto_instance *inst = crypto_tfm_ctx(tfm);
> >> + struct flexi_crypto_context *fctx;
> >> + enum flexi_cipher cipher_type;
> >> + const char *name;
> >> +
> >> + name = crypto_tfm_alg_name(tfm);
> >> + cipher_type = flexi_cipher_type(name);
> >> + if (cipher_type == CIPHER_INVALID) {
> >> + pr_err("unsupported cipher: %s\n", name);
> >> + return -EINVAL;
> >> + }
> >> +
> >> + /* fill crypto context */
> >> + fctx = inst->u.fctx;
> >> + fctx->flags = 0;
> >> + fctx->w0.cipher_type = cipher_type;
> >> + fctx->w0.aes_keylen = aes_keylen;
> >> + fctx->w0.iv_source = IV_FROM_DPTR;
> >> + fctx->flags = cpu_to_be64(*(u64 *)&fctx->w0);
> >> + /* copy the key to context */
> >> + memcpy(fctx->crypto.u.key, key, keylen);
> >
> > Could you help me finding the location where this memory is zeroized upon
> > release?
>
> Currently, we are not zeroized the context in release.
> We are doing it at the time of allocation.

You store a key in a piece of heap memory. I guess you want to zeroize that
key memory before releasing?


Ciao
Stephan