[PATCH v6 27/35] misc/mei/hdcp: Verify H_prime

[Shankar, Uma]

>-----Original Message-----
>From: C, Ramalingam
>Sent: Saturday, July 14, 2018 8:45 AM
>To: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org;
>daniel at ffwll.ch; seanpaul at chromium.org; Winkler, Tomas
><tomas.winkler at intel.com>; Usyskin, Alexander <alexander.usyskin at intel.com>;
>Shankar, Uma <uma.shankar at intel.com>
>Cc: Sharma, Shashank <shashank.sharma at intel.com>; C, Ramalingam
><ramalingam.c at intel.com>
>Subject: [PATCH v6 27/35] misc/mei/hdcp: Verify H_prime
>
>Requests for the verification of AKE_Send_H_prime.
>
>ME will calculate the H and comparing it with received H_Prime.
>The result will be returned as status.
>
>Here AKE_Send_H_prime is a HDCP2.2 Authentication msg.
>
>v2:
>  Rebased.
>v3:
>  cldev is passed as first parameter [Tomas]
>  Redundant comments and cast are removed [Tomas]
>v4:
>  %zd for ssize_t [Alexander]
>  %s/return -1/return -EIO [Alexander]
>  Styles and typos fixed [Uma]
>v5:
>  Rebased.
>v6:
>  No change.
>

Looks ok to me.
Reviewed-by: Uma Shankar <uma.shankar at intel.com>

>Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
>---
> drivers/misc/mei/hdcp/mei_hdcp.c | 61
>+++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 60 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c
>b/drivers/misc/mei/hdcp/mei_hdcp.c
>index 7d35066f21e2..d455d4e54f46 100644
>--- a/drivers/misc/mei/hdcp/mei_hdcp.c
>+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
>@@ -187,12 +187,71 @@ mei_verify_receiver_cert_prepare_km(struct
>mei_cl_device *cldev,
> 	return 0;
> }
>
>+/*
>+ * mei_verify_hprime:
>+ *	Function to verify AKE_Send_H_prime received, through ME FW.
>+ *
>+ * cldev		: Pointer for mei client device
>+ * data			: Intel HW specific Data
>+ * rx_hprime		: Pointer for AKE_Send_H_prime
>+ * hprime_sz		: Input buffer size
>+ *
>+ * Returns 0 on Success, <0 on Failure
>+ */
>+static int mei_verify_hprime(struct mei_cl_device *cldev,
>+			     struct mei_hdcp_data *data,
>+			     struct hdcp2_ake_send_hprime *rx_hprime) {
>+	struct wired_cmd_ake_send_hprime_in send_hprime_in = { { 0 } };
>+	struct wired_cmd_ake_send_hprime_out send_hprime_out = { { 0 } };
>+	struct device *dev;
>+	ssize_t byte;
>+
>+	if (!data || !rx_hprime)
>+		return -EINVAL;
>+
>+	dev = &cldev->dev;
>+
>+	send_hprime_in.header.api_version = HDCP_API_VERSION;
>+	send_hprime_in.header.command_id = WIRED_AKE_SEND_HPRIME;
>+	send_hprime_in.header.status = ME_HDCP_STATUS_SUCCESS;
>+	send_hprime_in.header.buffer_len =
>+WIRED_CMD_BUF_LEN_AKE_SEND_HPRIME_IN;
>+
>+	send_hprime_in.port.integrated_port_type = data->port_type;
>+	send_hprime_in.port.physical_port = data->port;
>+
>+	memcpy(send_hprime_in.h_prime, rx_hprime->h_prime,
>+	       sizeof(rx_hprime->h_prime));
>+
>+	byte = mei_cldev_send(cldev, (u8 *)&send_hprime_in,
>+			      sizeof(send_hprime_in));
>+	if (byte < 0) {
>+		dev_dbg(dev, "mei_cldev_send failed. %zd\n", byte);
>+		return byte;
>+	}
>+
>+	byte = mei_cldev_recv(cldev, (u8 *)&send_hprime_out,
>+			      sizeof(send_hprime_out));
>+	if (byte < 0) {
>+		dev_dbg(dev, "mei_cldev_recv failed. %zd\n", byte);
>+		return byte;
>+	}
>+
>+	if (send_hprime_out.header.status != ME_HDCP_STATUS_SUCCESS) {
>+		dev_dbg(dev, "ME cmd 0x%08X Failed. Status: 0x%X\n",
>+			WIRED_AKE_SEND_HPRIME,
>send_hprime_out.header.status);
>+		return -EIO;
>+	}
>+
>+	return 0;
>+}
>+
> struct i915_hdcp_component_ops mei_hdcp_component_ops = {
> 	.owner					= THIS_MODULE,
> 	.initiate_hdcp2_session			= mei_initiate_hdcp2_session,
> 	.verify_receiver_cert_prepare_km	=
> 					mei_verify_receiver_cert_prepare_km,
>-	.verify_hprime				= NULL,
>+	.verify_hprime				= mei_verify_hprime,
> 	.store_pairing_info			= NULL,
> 	.initiate_locality_check		= NULL,
> 	.verify_lprime				= NULL,
>--
>2.7.4