[Intel-gfx] [PATCH v3 09/40] misc/mei/hdcp: Verify Receiver Cert and prepare km

[Ramalingam C]

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]

Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
---
 drivers/misc/mei/hdcp/mei_hdcp.c | 82 ++++++++++++++++++++++++++++++++++++++++
 include/linux/mei_hdcp.h         | 17 +++++++++
 2 files changed, 99 insertions(+)

diff --git a/drivers/misc/mei/hdcp/mei_hdcp.c b/drivers/misc/mei/hdcp/mei_hdcp.c
index 7caee0947761..181994529058 100644
--- a/drivers/misc/mei/hdcp/mei_hdcp.c
+++ b/drivers/misc/mei/hdcp/mei_hdcp.c
@@ -104,6 +104,88 @@ int mei_initiate_hdcp2_session(struct mei_cl_device *cldev,
 }
 EXPORT_SYMBOL(mei_initiate_hdcp2_session);
 
+/**
+ * mei_verify_receiver_cert_prepare_km:
+ *	Function to verify the Receiver Certificate AKE_Send_Cert
+ *	and prepare AKE_Stored_Km or AKE_No_Stored_Km
+ *
+ * @cldev		: Pointer for mei client device
+ * @data		: Intel HW specific Data
+ * @rx_cert		: Pointer for AKE_Send_Cert
+ * @km_stored		: Pointer for pairing status flag
+ * @ek_pub_km		: Pointer for output msg
+ * @msg_sz		: Pointer for size of AKE_XXXXX_Km
+ *
+ * Returns 0 on Success, <0 on Failure
+ */
+int
+mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
+				    struct mei_hdcp_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 device *dev;
+	ssize_t byte;
+
+	if (!data || !rx_cert || !km_stored || !ek_pub_km || !msg_sz)
+		return -EINVAL;
+
+	dev = &cldev->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 = data->port;
+
+	memcpy(&verify_rxcert_in.cert_rx, &rx_cert->cert_rx,
+	       sizeof(rx_cert->cert_rx));
+	memcpy(verify_rxcert_in.r_rx, &rx_cert->r_rx, sizeof(rx_cert->r_rx));
+	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: %d\n", (int)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: %d\n", (int)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 -1;
+	}
+
+	*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;
+}
+EXPORT_SYMBOL(mei_verify_receiver_cert_prepare_km);
+
 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 bb4f27d3abcb..314b15f6afc0 100644
--- a/include/linux/mei_hdcp.h
+++ b/include/linux/mei_hdcp.h
@@ -109,6 +109,13 @@ int mei_cldev_unregister_notify(struct notifier_block *nb);
 int mei_initiate_hdcp2_session(struct mei_cl_device *cldev,
 			       struct mei_hdcp_data *data,
 			       struct hdcp2_ake_init *ake_data);
+int
+mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
+				    struct mei_hdcp_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);
 #else
 static int mei_cldev_register_notify(struct notifier_block *nb)
 {
@@ -125,5 +132,15 @@ int mei_initiate_hdcp2_session(struct mei_cl_device *cldev,
 {
 	return -ENODEV;
 }
+static inline int
+mei_verify_receiver_cert_prepare_km(struct mei_cl_device *cldev,
+				    struct mei_hdcp_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)
+{
+	return -ENODEV;
+}
 #endif /* defined (CONFIG_INTEL_MEI_HDCP) */
 #endif /* defined (_LINUX_MEI_HDCP_H) */
-- 
2.7.4