[PATCH v9 12/39] drm/i915: Implement HDCP2.2 repeater authentication
Daniel Vetter
daniel at ffwll.ch
Wed Dec 19 14:48:01 UTC 2018
On Thu, Dec 13, 2018 at 09:31:14AM +0530, Ramalingam C wrote:
> Implements the HDCP2.2 repeaters authentication steps such as verifying
> the downstream topology and sending stream management information.
>
> v2: Rebased.
> v3:
> -EINVAL is returned for topology error and rollover scenario.
> Endianness conversion func from drm_hdcp.h is used [Uma]
> v4:
> Rebased as part of patches reordering.
> Defined the mei service functions [Daniel]
> v5:
> Redefined the mei service functions as per comp redesign.
> v6:
> %s/uintxx_t/uxx
> Check for comp_master is removed.
> v7:
> Adjust to the new mei interface.
> style issue fixed.
> v8:
> drm_hdcp.h change is moved into separate patch [Daniel]
>
> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> ---
> drivers/gpu/drm/i915/intel_hdcp.c | 123 +++++++++++++++++++++++++++++++++++++-
> 1 file changed, 121 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_hdcp.c b/drivers/gpu/drm/i915/intel_hdcp.c
> index f1f0ef294e20..b52da5c3159d 100644
> --- a/drivers/gpu/drm/i915/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/intel_hdcp.c
> @@ -978,7 +978,7 @@ static int hdcp2_prepare_skey(struct intel_connector *connector,
> return ret;
> }
>
> -static __attribute__((unused)) int
> +static int
> hdcp2_verify_rep_topology_prepare_ack(struct intel_connector *connector,
> struct hdcp2_rep_send_receiverid_list
> *rep_topology,
> @@ -999,7 +999,7 @@ hdcp2_verify_rep_topology_prepare_ack(struct intel_connector *connector,
> return ret;
> }
>
> -static __attribute__((unused)) int
> +static int
> hdcp2_verify_mprime(struct intel_connector *connector,
> struct hdcp2_rep_stream_ready *stream_ready)
> {
> @@ -1182,6 +1182,119 @@ static int hdcp2_session_key_exchange(struct intel_connector *connector)
> return 0;
> }
>
> +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->shim;
> + int ret;
> +
> + /* Prepare RepeaterAuth_Stream_Manage msg */
> + msgs.stream_manage.msg_id = HDCP_2_2_REP_STREAM_MANAGE;
> + drm_hdcp2_u32_to_seq_num(msgs.stream_manage.seq_num_m, 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->port_data.seq_num_m = hdcp->seq_num_m;
> + hdcp->port_data.streams[0].stream_type = hdcp->content_type;
> +
> + ret = hdcp2_verify_mprime(connector, &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;
> + }
> +
> + 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->shim;
> + u8 *rx_info;
> + u32 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;
There's a 2s timeout here that we're not checking, but again probably
follow-up patch.
> +
> + 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 -EINVAL;
> + }
> +
> + /* Converting and Storing the seq_num_v to local variable as DWORD */
> + drm_hdcp2_seq_num_to_u32(&seq_num_v, 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 -EINVAL;
> + }
> +
> + ret = hdcp2_verify_rep_topology_prepare_ack(connector,
> + &msgs.recvid_list,
> + &msgs.rep_ack);
> + if (ret < 0)
> + return ret;
Spec talks about type0 vs type1 here, but for now we can ignore that.
> +
> + 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);
> @@ -1223,6 +1336,12 @@ 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;
> + }
> }
Spec for receiver auth is a bit more confusing than usual, but I think
this matches.
Reviewed-by: Daniel Vetter <daniel.vetter at ffwll.ch>
>
> hdcp->port_data.streams[0].stream_type = hdcp->content_type;
> --
> 2.7.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
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