Subject: Re: [PATCH 07/12] nvme: Implement In-Band authentication
To:     Hannes Reinecke <hare@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>, Keith Busch <keith.busch@wdc.com>,
        linux-nvme@lists.infradead.org,
        Herbert Xu <herberg@gondor.apana.org.au>,
        David Miller <davem@davemloft.org>,
        linux-crypto@vger.kernel.org
References: <20211122074727.25988-1-hare@suse.de>
 <20211122074727.25988-8-hare@suse.de>
From:   Sagi Grimberg <sagi@grimberg.me>
Message-ID: <8f6c144d-0354-2753-ab58-1f5cabcafbdd@grimberg.me>
Date:   Mon, 22 Nov 2021 10:12:38 +0200
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> +int nvme_auth_generate_key(struct nvme_ctrl *ctrl, u8 *secret, bool set_ctrl)

Maybe instead of set_ctrl introduct struct dhchap_key and pass a pointer
into that?

> +{
> +	u8 *key;
> +	size_t key_len;
> +	u8 key_hash;
> +
> +	if (!secret)
> +		return 0;
> +
> +	if (sscanf(secret, "DHHC-1:%hhd:%*s:", &key_hash) != 1)
> +		return -EINVAL;
> +
> +	/* Pass in the secret without the 'DHHC-1:XX:' prefix */
> +	key = nvme_auth_extract_secret(secret + 10, key_hash,
> +				       &key_len);
> +	if (IS_ERR(key)) {
> +		dev_dbg(ctrl->device, "failed to extract key, error %ld\n",
> +			PTR_ERR(key));
> +		return PTR_ERR(key);
> +	}
> +
> +	if (set_ctrl) {
> +		ctrl->dhchap_ctrl_key = key;
> +		ctrl->dhchap_ctrl_key_len = key_len;
> +		ctrl->dhchap_ctrl_key_hash = key_hash;
> +	} else {
> +		ctrl->dhchap_key = key;
> +		ctrl->dhchap_key_len = key_len;
> +		ctrl->dhchap_key_hash = key_hash;
> +	}

Then it becomes:
	dhchap_key->key = key;
	dhchap_key->len = key_len;
	dhchap_key->hash = key_hash;