[PATCH v14 22/33] misc/mei/hdcp: Verify Receiver Cert and prepare km

[Winkler, Tomas]

> Requests for verification for receiver certification and also the preparation for
> next AKE auth message with km.
> 
> On Success ME FW validate the HDCP2.2 receivers certificate and do the
> revocation check on the receiver ID. AKE_Stored_Km will be prepared if the
> receiver is already paired, else AKE_No_Stored_Km will be prepared.
> 
> Here AKE_Stored_Km and AKE_No_Stored_Km are HDCP2.2 protocol msgs.
> 
> v2: Rebased.
> v3:
>   cldev is passed as first parameter [Tomas]
>   Redundant comments and cast are removed [Tomas]
> v4:
>   %zd is used for ssize_t [Alexander]
>   %s/return -1/return -EIO [Alexander]
> v5: Rebased.
> v6:
>   Collected the Rb-ed by.
>   Rebasing.
> v7:
>   Adjust to the new mei interface.
>   Fix for Kdoc.
> v8:
>   K-Doc Addition. [Tomas]
>   memcpy for const length.
> v9:
>   renamed func as mei_hdcp_* [Tomas]
>   Inline function is defined for DDI index [Tomas]
> v10:
>   Fixed the conversion of u8 to bool [Tomas]
>   K-Doc fix [Tomas]
> 
> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> Reviewed-by: Uma Shankar <uma.shankar at intel.com>
> Acked-by: Tomas Winkler <tomas.winkler at intel.com>
LGTM
> ---
>  drivers/misc/mei/hdcp/mei_hdcp.c | 83
> +++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 82 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c
> b/drivers/misc/mei/hdcp/mei_hdcp.c
> index 952bae79dd02..922c6a76bb9f 100644
> --- a/drivers/misc/mei/hdcp/mei_hdcp.c
> +++ b/drivers/misc/mei/hdcp/mei_hdcp.c
> @@ -102,11 +102,92 @@ mei_hdcp_initiate_session(struct device *dev, struct
> hdcp_port_data *data,
>  	return 0;
>  }
> 
> +/**
> + * mei_hdcp_verify_receiver_cert_prepare_km() - Verify the Receiver
> +Certificate
> + * AKE_Send_Cert and prepare AKE_Stored_Km/AKE_No_Stored_Km
> + * @dev: device corresponding to the mei_cl_device
> + * @data: Intel HW specific hdcp data
> + * @rx_cert: AKE_Send_Cert for verification
> + * @km_stored: Pairing status flag output
> + * @ek_pub_km: AKE_Stored_Km/AKE_No_Stored_Km output msg
> + * @msg_sz : size of AKE_XXXXX_Km output msg
> + *
> + * Return: 0 on Success, <0 on Failure
> + */
> +static int
> +mei_hdcp_verify_receiver_cert_prepare_km(struct device *dev,
> +					 struct hdcp_port_data *data,
> +					 struct hdcp2_ake_send_cert *rx_cert,
> +					 bool *km_stored,
> +					 struct hdcp2_ake_no_stored_km
> +								*ek_pub_km,
> +					 size_t *msg_sz)
> +{
> +	struct wired_cmd_verify_receiver_cert_in verify_rxcert_in = { { 0 } };
> +	struct wired_cmd_verify_receiver_cert_out verify_rxcert_out = { { 0 } };
> +	struct mei_cl_device *cldev;
> +	ssize_t byte;
> +
> +	if (!dev || !data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
> +		return -EINVAL;
> +
> +	cldev = to_mei_cl_device(dev);
> +
> +	verify_rxcert_in.header.api_version = HDCP_API_VERSION;
> +	verify_rxcert_in.header.command_id =
> WIRED_VERIFY_RECEIVER_CERT;
> +	verify_rxcert_in.header.status = ME_HDCP_STATUS_SUCCESS;
> +	verify_rxcert_in.header.buffer_len =
> +
> 	WIRED_CMD_BUF_LEN_VERIFY_RECEIVER_CERT_IN;
> +
> +	verify_rxcert_in.port.integrated_port_type = data->port_type;
> +	verify_rxcert_in.port.physical_port = mei_get_ddi_index(data->port);
> +
> +	verify_rxcert_in.cert_rx = rx_cert->cert_rx;
> +	memcpy(verify_rxcert_in.r_rx, &rx_cert->r_rx, HDCP_2_2_RRX_LEN);
> +	memcpy(verify_rxcert_in.rx_caps, rx_cert->rx_caps,
> +HDCP_2_2_RXCAPS_LEN);
> +
> +	byte = mei_cldev_send(cldev, (u8 *)&verify_rxcert_in,
> +			      sizeof(verify_rxcert_in));
> +	if (byte < 0) {
> +		dev_dbg(dev, "mei_cldev_send failed: %zd\n", byte);
> +		return byte;
> +	}
> +
> +	byte = mei_cldev_recv(cldev, (u8 *)&verify_rxcert_out,
> +			      sizeof(verify_rxcert_out));
> +	if (byte < 0) {
> +		dev_dbg(dev, "mei_cldev_recv failed: %zd\n", byte);
> +		return byte;
> +	}
> +
> +	if (verify_rxcert_out.header.status != ME_HDCP_STATUS_SUCCESS) {
> +		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
> +			WIRED_VERIFY_RECEIVER_CERT,
> +			verify_rxcert_out.header.status);
> +		return -EIO;
> +	}
> +
> +	*km_stored = !!verify_rxcert_out.km_stored;
> +	if (verify_rxcert_out.km_stored) {
> +		ek_pub_km->msg_id = HDCP_2_2_AKE_STORED_KM;
> +		*msg_sz = sizeof(struct hdcp2_ake_stored_km);
> +	} else {
> +		ek_pub_km->msg_id = HDCP_2_2_AKE_NO_STORED_KM;
> +		*msg_sz = sizeof(struct hdcp2_ake_no_stored_km);
> +	}
> +
> +	memcpy(ek_pub_km->e_kpub_km, &verify_rxcert_out.ekm_buff,
> +	       sizeof(verify_rxcert_out.ekm_buff));
> +
> +	return 0;
> +}
> +
>  static __attribute__((unused))
>  struct i915_hdcp_component_ops mei_hdcp_ops = {
>  	.owner = THIS_MODULE,
>  	.initiate_hdcp2_session = mei_hdcp_initiate_session,
> -	.verify_receiver_cert_prepare_km = NULL,
> +	.verify_receiver_cert_prepare_km =
> +				mei_hdcp_verify_receiver_cert_prepare_km,
>  	.verify_hprime = NULL,
>  	.store_pairing_info = NULL,
>  	.initiate_locality_check = NULL,
> --
> 2.7.4