mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-30 12:49:36 +00:00
![Ramalingam C](/assets/img/avatar_default.png)
In the kernel documentation, HDCP specifications links are shared as a reference for SRM table format. v2: Fixed small nits. [Shashank] Signed-off-by: Ramalingam C <ramalingam.c@intel.com> Reviewed-by: Shashank Sharma <shashank.sharma@intel.com> Acked-by: Pekka Paalanen <pekka.paalanen@collabora.com> Acked-by: Jani Nikula <jani.nikula@intel.com> Link: https://patchwork.freedesktop.org/patch/320968/?series=57232&rev=14
457 lines
13 KiB
C
457 lines
13 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/*
|
|
* Copyright (C) 2019 Intel Corporation.
|
|
*
|
|
* Authors:
|
|
* Ramalingam C <ramalingam.c@intel.com>
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/err.h>
|
|
#include <linux/gfp.h>
|
|
#include <linux/export.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/firmware.h>
|
|
|
|
#include <drm/drm_hdcp.h>
|
|
#include <drm/drm_sysfs.h>
|
|
#include <drm/drm_print.h>
|
|
#include <drm/drm_device.h>
|
|
#include <drm/drm_property.h>
|
|
#include <drm/drm_mode_object.h>
|
|
#include <drm/drm_connector.h>
|
|
|
|
#include "drm_internal.h"
|
|
|
|
static struct hdcp_srm {
|
|
u32 revoked_ksv_cnt;
|
|
u8 *revoked_ksv_list;
|
|
|
|
/* Mutex to protect above struct member */
|
|
struct mutex mutex;
|
|
} *srm_data;
|
|
|
|
static inline void drm_hdcp_print_ksv(const u8 *ksv)
|
|
{
|
|
DRM_DEBUG("\t%#02x, %#02x, %#02x, %#02x, %#02x\n",
|
|
ksv[0], ksv[1], ksv[2], ksv[3], ksv[4]);
|
|
}
|
|
|
|
static u32 drm_hdcp_get_revoked_ksv_count(const u8 *buf, u32 vrls_length)
|
|
{
|
|
u32 parsed_bytes = 0, ksv_count = 0, vrl_ksv_cnt, vrl_sz;
|
|
|
|
while (parsed_bytes < vrls_length) {
|
|
vrl_ksv_cnt = *buf;
|
|
ksv_count += vrl_ksv_cnt;
|
|
|
|
vrl_sz = (vrl_ksv_cnt * DRM_HDCP_KSV_LEN) + 1;
|
|
buf += vrl_sz;
|
|
parsed_bytes += vrl_sz;
|
|
}
|
|
|
|
/*
|
|
* When vrls are not valid, ksvs are not considered.
|
|
* Hence SRM will be discarded.
|
|
*/
|
|
if (parsed_bytes != vrls_length)
|
|
ksv_count = 0;
|
|
|
|
return ksv_count;
|
|
}
|
|
|
|
static u32 drm_hdcp_get_revoked_ksvs(const u8 *buf, u8 *revoked_ksv_list,
|
|
u32 vrls_length)
|
|
{
|
|
u32 parsed_bytes = 0, ksv_count = 0;
|
|
u32 vrl_ksv_cnt, vrl_ksv_sz, vrl_idx = 0;
|
|
|
|
do {
|
|
vrl_ksv_cnt = *buf;
|
|
vrl_ksv_sz = vrl_ksv_cnt * DRM_HDCP_KSV_LEN;
|
|
|
|
buf++;
|
|
|
|
DRM_DEBUG("vrl: %d, Revoked KSVs: %d\n", vrl_idx++,
|
|
vrl_ksv_cnt);
|
|
memcpy(revoked_ksv_list, buf, vrl_ksv_sz);
|
|
|
|
ksv_count += vrl_ksv_cnt;
|
|
revoked_ksv_list += vrl_ksv_sz;
|
|
buf += vrl_ksv_sz;
|
|
|
|
parsed_bytes += (vrl_ksv_sz + 1);
|
|
} while (parsed_bytes < vrls_length);
|
|
|
|
return ksv_count;
|
|
}
|
|
|
|
static inline u32 get_vrl_length(const u8 *buf)
|
|
{
|
|
return drm_hdcp_be24_to_cpu(buf);
|
|
}
|
|
|
|
static int drm_hdcp_parse_hdcp1_srm(const u8 *buf, size_t count)
|
|
{
|
|
struct hdcp_srm_header *header;
|
|
u32 vrl_length, ksv_count;
|
|
|
|
if (count < (sizeof(struct hdcp_srm_header) +
|
|
DRM_HDCP_1_4_VRL_LENGTH_SIZE + DRM_HDCP_1_4_DCP_SIG_SIZE)) {
|
|
DRM_ERROR("Invalid blob length\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
header = (struct hdcp_srm_header *)buf;
|
|
DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n",
|
|
header->srm_id,
|
|
be16_to_cpu(header->srm_version), header->srm_gen_no);
|
|
|
|
WARN_ON(header->reserved);
|
|
|
|
buf = buf + sizeof(*header);
|
|
vrl_length = get_vrl_length(buf);
|
|
if (count < (sizeof(struct hdcp_srm_header) + vrl_length) ||
|
|
vrl_length < (DRM_HDCP_1_4_VRL_LENGTH_SIZE +
|
|
DRM_HDCP_1_4_DCP_SIG_SIZE)) {
|
|
DRM_ERROR("Invalid blob length or vrl length\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Length of the all vrls combined */
|
|
vrl_length -= (DRM_HDCP_1_4_VRL_LENGTH_SIZE +
|
|
DRM_HDCP_1_4_DCP_SIG_SIZE);
|
|
|
|
if (!vrl_length) {
|
|
DRM_ERROR("No vrl found\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
buf += DRM_HDCP_1_4_VRL_LENGTH_SIZE;
|
|
ksv_count = drm_hdcp_get_revoked_ksv_count(buf, vrl_length);
|
|
if (!ksv_count) {
|
|
DRM_DEBUG("Revoked KSV count is 0\n");
|
|
return count;
|
|
}
|
|
|
|
kfree(srm_data->revoked_ksv_list);
|
|
srm_data->revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN,
|
|
GFP_KERNEL);
|
|
if (!srm_data->revoked_ksv_list) {
|
|
DRM_ERROR("Out of Memory\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
if (drm_hdcp_get_revoked_ksvs(buf, srm_data->revoked_ksv_list,
|
|
vrl_length) != ksv_count) {
|
|
srm_data->revoked_ksv_cnt = 0;
|
|
kfree(srm_data->revoked_ksv_list);
|
|
return -EINVAL;
|
|
}
|
|
|
|
srm_data->revoked_ksv_cnt = ksv_count;
|
|
return count;
|
|
}
|
|
|
|
static int drm_hdcp_parse_hdcp2_srm(const u8 *buf, size_t count)
|
|
{
|
|
struct hdcp_srm_header *header;
|
|
u32 vrl_length, ksv_count, ksv_sz;
|
|
|
|
if (count < (sizeof(struct hdcp_srm_header) +
|
|
DRM_HDCP_2_VRL_LENGTH_SIZE + DRM_HDCP_2_DCP_SIG_SIZE)) {
|
|
DRM_ERROR("Invalid blob length\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
header = (struct hdcp_srm_header *)buf;
|
|
DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n",
|
|
header->srm_id & DRM_HDCP_SRM_ID_MASK,
|
|
be16_to_cpu(header->srm_version), header->srm_gen_no);
|
|
|
|
if (header->reserved)
|
|
return -EINVAL;
|
|
|
|
buf = buf + sizeof(*header);
|
|
vrl_length = get_vrl_length(buf);
|
|
|
|
if (count < (sizeof(struct hdcp_srm_header) + vrl_length) ||
|
|
vrl_length < (DRM_HDCP_2_VRL_LENGTH_SIZE +
|
|
DRM_HDCP_2_DCP_SIG_SIZE)) {
|
|
DRM_ERROR("Invalid blob length or vrl length\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* Length of the all vrls combined */
|
|
vrl_length -= (DRM_HDCP_2_VRL_LENGTH_SIZE +
|
|
DRM_HDCP_2_DCP_SIG_SIZE);
|
|
|
|
if (!vrl_length) {
|
|
DRM_ERROR("No vrl found\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
buf += DRM_HDCP_2_VRL_LENGTH_SIZE;
|
|
ksv_count = (*buf << 2) | DRM_HDCP_2_KSV_COUNT_2_LSBITS(*(buf + 1));
|
|
if (!ksv_count) {
|
|
DRM_DEBUG("Revoked KSV count is 0\n");
|
|
return count;
|
|
}
|
|
|
|
kfree(srm_data->revoked_ksv_list);
|
|
srm_data->revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN,
|
|
GFP_KERNEL);
|
|
if (!srm_data->revoked_ksv_list) {
|
|
DRM_ERROR("Out of Memory\n");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
ksv_sz = ksv_count * DRM_HDCP_KSV_LEN;
|
|
buf += DRM_HDCP_2_NO_OF_DEV_PLUS_RESERVED_SZ;
|
|
|
|
DRM_DEBUG("Revoked KSVs: %d\n", ksv_count);
|
|
memcpy(srm_data->revoked_ksv_list, buf, ksv_sz);
|
|
|
|
srm_data->revoked_ksv_cnt = ksv_count;
|
|
return count;
|
|
}
|
|
|
|
static inline bool is_srm_version_hdcp1(const u8 *buf)
|
|
{
|
|
return *buf == (u8)(DRM_HDCP_1_4_SRM_ID << 4);
|
|
}
|
|
|
|
static inline bool is_srm_version_hdcp2(const u8 *buf)
|
|
{
|
|
return *buf == (u8)(DRM_HDCP_2_SRM_ID << 4 | DRM_HDCP_2_INDICATOR);
|
|
}
|
|
|
|
static void drm_hdcp_srm_update(const u8 *buf, size_t count)
|
|
{
|
|
if (count < sizeof(struct hdcp_srm_header))
|
|
return;
|
|
|
|
if (is_srm_version_hdcp1(buf))
|
|
drm_hdcp_parse_hdcp1_srm(buf, count);
|
|
else if (is_srm_version_hdcp2(buf))
|
|
drm_hdcp_parse_hdcp2_srm(buf, count);
|
|
}
|
|
|
|
static void drm_hdcp_request_srm(struct drm_device *drm_dev)
|
|
{
|
|
char fw_name[36] = "display_hdcp_srm.bin";
|
|
const struct firmware *fw;
|
|
|
|
int ret;
|
|
|
|
ret = request_firmware_direct(&fw, (const char *)fw_name,
|
|
drm_dev->dev);
|
|
if (ret < 0)
|
|
goto exit;
|
|
|
|
if (fw->size && fw->data)
|
|
drm_hdcp_srm_update(fw->data, fw->size);
|
|
|
|
exit:
|
|
release_firmware(fw);
|
|
}
|
|
|
|
/**
|
|
* drm_hdcp_check_ksvs_revoked - Check the revoked status of the IDs
|
|
*
|
|
* @drm_dev: drm_device for which HDCP revocation check is requested
|
|
* @ksvs: List of KSVs (HDCP receiver IDs)
|
|
* @ksv_count: KSV count passed in through @ksvs
|
|
*
|
|
* This function reads the HDCP System renewability Message(SRM Table)
|
|
* from userspace as a firmware and parses it for the revoked HDCP
|
|
* KSVs(Receiver IDs) detected by DCP LLC. Once the revoked KSVs are known,
|
|
* revoked state of the KSVs in the list passed in by display drivers are
|
|
* decided and response is sent.
|
|
*
|
|
* SRM should be presented in the name of "display_hdcp_srm.bin".
|
|
*
|
|
* Format of the SRM table, that userspace needs to write into the binary file,
|
|
* is defined at:
|
|
* 1. Renewability chapter on 55th page of HDCP 1.4 specification
|
|
* https://www.digital-cp.com/sites/default/files/specifications/HDCP%20Specification%20Rev1_4_Secure.pdf
|
|
* 2. Renewability chapter on 63rd page of HDCP 2.2 specification
|
|
* https://www.digital-cp.com/sites/default/files/specifications/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdf
|
|
*
|
|
* Returns:
|
|
* TRUE on any of the KSV is revoked, else FALSE.
|
|
*/
|
|
bool drm_hdcp_check_ksvs_revoked(struct drm_device *drm_dev, u8 *ksvs,
|
|
u32 ksv_count)
|
|
{
|
|
u32 rev_ksv_cnt, cnt, i, j;
|
|
u8 *rev_ksv_list;
|
|
|
|
if (!srm_data)
|
|
return false;
|
|
|
|
mutex_lock(&srm_data->mutex);
|
|
drm_hdcp_request_srm(drm_dev);
|
|
|
|
rev_ksv_cnt = srm_data->revoked_ksv_cnt;
|
|
rev_ksv_list = srm_data->revoked_ksv_list;
|
|
|
|
/* If the Revoked ksv list is empty */
|
|
if (!rev_ksv_cnt || !rev_ksv_list) {
|
|
mutex_unlock(&srm_data->mutex);
|
|
return false;
|
|
}
|
|
|
|
for (cnt = 0; cnt < ksv_count; cnt++) {
|
|
rev_ksv_list = srm_data->revoked_ksv_list;
|
|
for (i = 0; i < rev_ksv_cnt; i++) {
|
|
for (j = 0; j < DRM_HDCP_KSV_LEN; j++)
|
|
if (ksvs[j] != rev_ksv_list[j]) {
|
|
break;
|
|
} else if (j == (DRM_HDCP_KSV_LEN - 1)) {
|
|
DRM_DEBUG("Revoked KSV is ");
|
|
drm_hdcp_print_ksv(ksvs);
|
|
mutex_unlock(&srm_data->mutex);
|
|
return true;
|
|
}
|
|
/* Move the offset to next KSV in the revoked list */
|
|
rev_ksv_list += DRM_HDCP_KSV_LEN;
|
|
}
|
|
|
|
/* Iterate to next ksv_offset */
|
|
ksvs += DRM_HDCP_KSV_LEN;
|
|
}
|
|
mutex_unlock(&srm_data->mutex);
|
|
return false;
|
|
}
|
|
EXPORT_SYMBOL_GPL(drm_hdcp_check_ksvs_revoked);
|
|
|
|
int drm_setup_hdcp_srm(struct class *drm_class)
|
|
{
|
|
srm_data = kzalloc(sizeof(*srm_data), GFP_KERNEL);
|
|
if (!srm_data)
|
|
return -ENOMEM;
|
|
mutex_init(&srm_data->mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void drm_teardown_hdcp_srm(struct class *drm_class)
|
|
{
|
|
if (srm_data) {
|
|
kfree(srm_data->revoked_ksv_list);
|
|
kfree(srm_data);
|
|
}
|
|
}
|
|
|
|
static struct drm_prop_enum_list drm_cp_enum_list[] = {
|
|
{ DRM_MODE_CONTENT_PROTECTION_UNDESIRED, "Undesired" },
|
|
{ DRM_MODE_CONTENT_PROTECTION_DESIRED, "Desired" },
|
|
{ DRM_MODE_CONTENT_PROTECTION_ENABLED, "Enabled" },
|
|
};
|
|
DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)
|
|
|
|
static struct drm_prop_enum_list drm_hdcp_content_type_enum_list[] = {
|
|
{ DRM_MODE_HDCP_CONTENT_TYPE0, "HDCP Type0" },
|
|
{ DRM_MODE_HDCP_CONTENT_TYPE1, "HDCP Type1" },
|
|
};
|
|
DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name,
|
|
drm_hdcp_content_type_enum_list)
|
|
|
|
/**
|
|
* drm_connector_attach_content_protection_property - attach content protection
|
|
* property
|
|
*
|
|
* @connector: connector to attach CP property on.
|
|
* @hdcp_content_type: is HDCP Content Type property needed for connector
|
|
*
|
|
* This is used to add support for content protection on select connectors.
|
|
* Content Protection is intentionally vague to allow for different underlying
|
|
* technologies, however it is most implemented by HDCP.
|
|
*
|
|
* When hdcp_content_type is true enum property called HDCP Content Type is
|
|
* created (if it is not already) and attached to the connector.
|
|
*
|
|
* This property is used for sending the protected content's stream type
|
|
* from userspace to kernel on selected connectors. Protected content provider
|
|
* will decide their type of their content and declare the same to kernel.
|
|
*
|
|
* Content type will be used during the HDCP 2.2 authentication.
|
|
* Content type will be set to &drm_connector_state.hdcp_content_type.
|
|
*
|
|
* The content protection will be set to &drm_connector_state.content_protection
|
|
*
|
|
* When kernel triggered content protection state change like DESIRED->ENABLED
|
|
* and ENABLED->DESIRED, will use drm_hdcp_update_content_protection() to update
|
|
* the content protection state of a connector.
|
|
*
|
|
* Returns:
|
|
* Zero on success, negative errno on failure.
|
|
*/
|
|
int drm_connector_attach_content_protection_property(
|
|
struct drm_connector *connector, bool hdcp_content_type)
|
|
{
|
|
struct drm_device *dev = connector->dev;
|
|
struct drm_property *prop =
|
|
dev->mode_config.content_protection_property;
|
|
|
|
if (!prop)
|
|
prop = drm_property_create_enum(dev, 0, "Content Protection",
|
|
drm_cp_enum_list,
|
|
ARRAY_SIZE(drm_cp_enum_list));
|
|
if (!prop)
|
|
return -ENOMEM;
|
|
|
|
drm_object_attach_property(&connector->base, prop,
|
|
DRM_MODE_CONTENT_PROTECTION_UNDESIRED);
|
|
dev->mode_config.content_protection_property = prop;
|
|
|
|
if (!hdcp_content_type)
|
|
return 0;
|
|
|
|
prop = dev->mode_config.hdcp_content_type_property;
|
|
if (!prop)
|
|
prop = drm_property_create_enum(dev, 0, "HDCP Content Type",
|
|
drm_hdcp_content_type_enum_list,
|
|
ARRAY_SIZE(
|
|
drm_hdcp_content_type_enum_list));
|
|
if (!prop)
|
|
return -ENOMEM;
|
|
|
|
drm_object_attach_property(&connector->base, prop,
|
|
DRM_MODE_HDCP_CONTENT_TYPE0);
|
|
dev->mode_config.hdcp_content_type_property = prop;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(drm_connector_attach_content_protection_property);
|
|
|
|
/**
|
|
* drm_hdcp_update_content_protection - Updates the content protection state
|
|
* of a connector
|
|
*
|
|
* @connector: drm_connector on which content protection state needs an update
|
|
* @val: New state of the content protection property
|
|
*
|
|
* This function can be used by display drivers, to update the kernel triggered
|
|
* content protection state changes of a drm_connector such as DESIRED->ENABLED
|
|
* and ENABLED->DESIRED. No uevent for DESIRED->UNDESIRED or ENABLED->UNDESIRED,
|
|
* as userspace is triggering such state change and kernel performs it without
|
|
* fail.This function update the new state of the property into the connector's
|
|
* state and generate an uevent to notify the userspace.
|
|
*/
|
|
void drm_hdcp_update_content_protection(struct drm_connector *connector,
|
|
u64 val)
|
|
{
|
|
struct drm_device *dev = connector->dev;
|
|
struct drm_connector_state *state = connector->state;
|
|
|
|
WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
|
|
if (state->content_protection == val)
|
|
return;
|
|
|
|
state->content_protection = val;
|
|
drm_sysfs_connector_status_event(connector,
|
|
dev->mode_config.content_protection_property);
|
|
}
|
|
EXPORT_SYMBOL(drm_hdcp_update_content_protection);
|