[PATCH v3 10/40] misc/mei/hdcp: Verify H_prime

[Ramalingam C]

Requests for the verifcation of AKE_Send_H_prime.

ME will calculation the H and comparing it with received H_Prime.
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]

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 58 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mei_hdcp.h         |  8 ++++++
 2 files changed, 66 insertions(+)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 181994529058..fa548310de7a 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -186,6 +186,64 @@ mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
 }
 EXPORT_SYMBOL(mei_verify_receiver_cert_prepare_km);
 
+/**
+ * mei_verify_hprime:
+ *	Function to verify AKE_Send_H_prime received
+ *
+ * @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
+ */
+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. %d\n", (int)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. %d\n", (int)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 -1;
+	}
+	return 0;
+}
+EXPORT_SYMBOL(mei_verify_hprime);
+
 void mei_cldev_state_notify_clients(struct mei_cl_device *cldev, bool enabled)
 {
 	if (enabled)
diff --git a/include/linux/mei_hdcp.h b/include/linux/mei_hdcp.h
index 314b15f6afc0..00bfde251ba4 100644
--- a/include/linux/mei_hdcp.h
+++ b/include/linux/mei_hdcp.h
@@ -116,6 +116,8 @@ mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
 				    bool *km_stored,
 				    struct hdcp2_ake_no_stored_km *ek_pub_km,
 				    size_t *msg_sz);
+int mei_verify_hprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_ake_send_hprime *rx_hprime);
 #else
 static int mei_cldev_register_notify(struct notifier_block *nb)
 {
@@ -142,5 +144,11 @@ mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
 {
 	return -ENODEV;
 }
+static inline
+int mei_verify_hprime(struct mei_cl_device *cldev, struct mei_hdcp_data *data,
+		      struct hdcp2_ake_send_hprime *rx_hprime)
+{
+	return -ENODEV;
+}
 #endif /* defined (CONFIG_INTEL_MEI_HDCP) */
 #endif /* defined (_LINUX_MEI_HDCP_H) */
-- 
2.7.4