Re: [PATCH v10 11/40] drm/i915: Implement HDCP2.2 repeater authentication

Shankar, Uma
2019-02-04T14:21:45Z

>-----Original Message-----
>From: C, Ramalingam
>Sent: Thursday, January 31, 2019 12:29 PM
>To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org;
>daniel.vetter@ffwll.ch; Winkler, Tomas <tomas.winkler@intel.com>; Shankar,
>Uma <uma.shankar@intel.com>
>Cc: C, Ramalingam <ramalingam.c@intel.com>
>Subject: [PATCH v10 11/40] 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:
> -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]
>v9:
> %s/__swab16/cpu_to_be16. [Tomas]
>
>Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
>Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

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

>---
> drivers/gpu/drm/i915/intel_hdcp.c | 125
>+++++++++++++++++++++++++++++++++++++-
> 1 file changed, 123 insertions(+), 2 deletions(-)
>
>diff --git a/drivers/gpu/drm/i915/intel_hdcp.c
>b/drivers/gpu/drm/i915/intel_hdcp.c
>index 1c81e17dc6c4..3b8d3a4b5e6e 100644
>--- a/drivers/gpu/drm/i915/intel_hdcp.c
>+++ b/drivers/gpu/drm/i915/intel_hdcp.c
>@@ -1032,7 +1032,7 @@ 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,
>@@ -1061,7 +1061,7 @@ 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) { @@ -
>1270,6 +1270,119 @@ 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 = cpu_to_be16(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;
>+
>+ 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 */
>+ seq_num_v =
>drm_hdcp2_seq_num_to_u32(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;
>+
>+ 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);
>@@ -1303,6 +1416,14 @@ static int hdcp2_authenticate_sink(struct
>intel_connector *connector)
> return ret;
> }
>
>+ 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->port_data.streams[0].stream_type = hdcp->content_type;
> ret = hdcp2_authenticate_port(connector);
> if (ret < 0)
>--
>2.7.4