Re: [PATCH v3 24/40] drm/i915: Implement HDCP2.2 repeater authentication

[Ramalingam C <ramalingam.c@intel.com>]

On Monday 14 May 2018 02:38 PM, Shankar, Uma wrote:
>
>> -----Original Message-----
>> From: Intel-gfx [mailto:intel-gfx-bounces@lists.freedesktop.org] On Behalf Of
>> Ramalingam C
>> Sent: Tuesday, April 3, 2018 7:28 PM
>> To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org;
>> seanpaul@chromium.org; daniel@ffwll.ch; chris@chris-wilson.co.uk;
>> jani.nikula@linux.intel.com; Winkler, Tomas <tomas.winkler@intel.com>;
>> Usyskin, Alexander <alexander.usyskin@intel.com>
>> Cc: Vivi, Rodrigo <rodrigo.vivi@intel.com>
>> Subject: [Intel-gfx] [PATCH v3 24/40] drm/i915: Implement HDCP2.2 repeater
>> authentication
>>
>> Implements the HDCP2.2 repeaters authentication steps such as verifying the
>> downstream topology and sending stream management information.
>>
>> v2:
>>   Rebased.
>> v3:
>>   No Changes.
>>
>> Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_hdcp.c | 135
>> ++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 135 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c
>> b/drivers/gpu/drm/i915/intel_hdcp.c
>> index ee9b7519fe73..d70320da85e4 100644
>> --- a/drivers/gpu/drm/i915/intel_hdcp.c
>> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
>> @@ -1145,6 +1145,135 @@ static int hdcp2_session_key_exchange(struct
>> intel_connector *connector)
>> 	return 0;
>> }
>>
>> +/*
>> + * Lib endianness functions are aligned for 16/32/64 bits. Since here
>> +sequence
>> + * num is 24bits developed a small conversion function.
>> + */
>> +static inline void reverse_endianness(u8 *dest, size_t dst_sz, u8 *src)
> This function is already defined and used in mei layer. Define this in some
> common header file and use instead of duplicating it here.  May be in below file:
> <drm/drm_connector.h>
Sure.

--Ram
>> +{
>> +	u32 index;
>> +
>> +	if (dest != NULL && dst_sz != 0) {
>> +		for (index = 0; index < dst_sz && index < sizeof(u32);
>> +		     index++) {
>> +			dest[dst_sz - index - 1] = src[index];
>> +		}
>> +	}
>> +}
>> +
>> +static
>> +int hdcp2_propagate_stream_management_info(struct intel_connector
>> +*connector) {
>> +	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
>> +	struct intel_hdcp *hdcp = &connector->hdcp;
>> +	union {
>> +		struct hdcp2_rep_stream_manage stream_manage;
>> +		struct hdcp2_rep_stream_ready stream_ready;
>> +	} msgs;
>> +	const struct intel_hdcp_shim *shim = hdcp->hdcp_shim;
>> +	int ret;
>> +
>> +	/* Prepare RepeaterAuth_Stream_Manage msg */
>> +	msgs.stream_manage.msg_id = HDCP_2_2_REP_STREAM_MANAGE;
>> +	reverse_endianness(msgs.stream_manage.seq_num_m,
>> HDCP_2_2_SEQ_NUM_LEN,
>> +			   (u8 *)&hdcp->seq_num_m);
>> +
>> +	/* K no of streams is fixed as 1. Stored as big-endian. */
>> +	msgs.stream_manage.k = __swab16(1);
>> +
>> +	/* For HDMI this is forced to be 0x0. For DP SST also this is 0x0. */
>> +	msgs.stream_manage.streams[0].stream_id = 0;
>> +	msgs.stream_manage.streams[0].stream_type = hdcp->content_type;
>> +
>> +	/* Send it to Repeater */
>> +	ret = shim->write_2_2_msg(intel_dig_port, &msgs.stream_manage,
>> +				  sizeof(msgs.stream_manage));
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	ret = shim->read_2_2_msg(intel_dig_port,
>> HDCP_2_2_REP_STREAM_READY,
>> +				 &msgs.stream_ready,
>> sizeof(msgs.stream_ready));
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	hdcp->mei_data.seq_num_m = hdcp->seq_num_m;
>> +	hdcp->mei_data.streams[0].stream_type = hdcp->content_type;
>> +
>> +	ret = hdcp2_verify_mprime(hdcp,	&msgs.stream_ready);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	hdcp->seq_num_m++;
>> +
>> +	if (hdcp->seq_num_m > HDCP_2_2_SEQ_NUM_MAX) {
>> +		DRM_DEBUG_KMS("seq_num_m roll over.\n");
>> +		return -1;
>> +	}
> Leave a blank line.
>
>> +	return 0;
>> +}
>> +
>> +static
>> +int hdcp2_authenticate_repeater_topology(struct intel_connector
>> +*connector) {
>> +	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
>> +	struct intel_hdcp *hdcp = &connector->hdcp;
>> +	union {
>> +		struct hdcp2_rep_send_receiverid_list recvid_list;
>> +		struct hdcp2_rep_send_ack rep_ack;
>> +	} msgs;
>> +	const struct intel_hdcp_shim *shim = hdcp->hdcp_shim;
>> +	uint8_t *rx_info;
>> +	uint32_t seq_num_v;
>> +	int ret;
>> +
>> +	ret = shim->read_2_2_msg(intel_dig_port,
>> HDCP_2_2_REP_SEND_RECVID_LIST,
>> +				 &msgs.recvid_list, sizeof(msgs.recvid_list));
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	rx_info = msgs.recvid_list.rx_info;
>> +
>> +	if (HDCP_2_2_MAX_CASCADE_EXCEEDED(rx_info[1]) ||
>> +	    HDCP_2_2_MAX_DEVS_EXCEEDED(rx_info[1])) {
>> +		DRM_DEBUG_KMS("Topology Max Size Exceeded\n");
>> +		return -1;
>> +	}
>> +
>> +	/* Converting and Storing the seq_num_v to local variable as DWORD */
>> +	reverse_endianness((u8 *)&seq_num_v, HDCP_2_2_SEQ_NUM_LEN,
>> +			   msgs.recvid_list.seq_num_v);
>> +
>> +	if (seq_num_v < hdcp->seq_num_v) {
>> +		/* Roll over of the seq_num_v from repeater. Reauthenticate. */
>> +		DRM_DEBUG_KMS("Seq_num_v roll over.\n");
>> +		return -1;
>> +	}
>> +
>> +	ret = hdcp2_verify_rep_topology_prepare_ack(hdcp, &msgs.recvid_list,
>> +						    &msgs.rep_ack);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	hdcp->seq_num_v = seq_num_v;
>> +	ret = shim->write_2_2_msg(intel_dig_port, &msgs.rep_ack,
>> +				  sizeof(msgs.rep_ack));
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return 0;
>> +}
>> +
>> +static int hdcp2_authenticate_repeater(struct intel_connector
>> +*connector) {
>> +	int ret;
>> +
>> +	ret = hdcp2_authenticate_repeater_topology(connector);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	return hdcp2_propagate_stream_management_info(connector);
>> +}
>> +
>> static int hdcp2_authenticate_sink(struct intel_connector *connector)  {
>> 	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);
>> @@ -1186,6 +1315,12 @@ static int hdcp2_authenticate_sink(struct
>> intel_connector *connector)
>> 					       sizeof(stream_type_msg));
>> 		if (ret < 0)
>> 			return ret;
>> +	} else if (hdcp->is_repeater) {
>> +		ret = hdcp2_authenticate_repeater(connector);
>> +		if (ret < 0) {
>> +			DRM_DEBUG_KMS("Repeater Auth Failed. Err: %d\n",
>> ret);
>> +			return ret;
>> +		}
>> 	}
>>
>> 	hdcp->mei_data.streams[0].stream_type = hdcp->content_type;
>> --
>> 2.7.4
>>
>> _______________________________________________
>> Intel-gfx mailing list
>> Intel-gfx@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx