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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2019 Intel Corporation.4 *5 * Authors:6 * Ramalingam C <ramalingam.c@intel.com>7 */8 9#include <linux/device.h>10#include <linux/err.h>11#include <linux/gfp.h>12#include <linux/export.h>13#include <linux/slab.h>14#include <linux/firmware.h>15 16#include <drm/display/drm_hdcp_helper.h>17#include <drm/drm_sysfs.h>18#include <drm/drm_print.h>19#include <drm/drm_device.h>20#include <drm/drm_property.h>21#include <drm/drm_mode_object.h>22#include <drm/drm_connector.h>23 24static inline void drm_hdcp_print_ksv(const u8 *ksv)25{26 DRM_DEBUG("\t%#02x, %#02x, %#02x, %#02x, %#02x\n",27 ksv[0], ksv[1], ksv[2], ksv[3], ksv[4]);28}29 30static u32 drm_hdcp_get_revoked_ksv_count(const u8 *buf, u32 vrls_length)31{32 u32 parsed_bytes = 0, ksv_count = 0, vrl_ksv_cnt, vrl_sz;33 34 while (parsed_bytes < vrls_length) {35 vrl_ksv_cnt = *buf;36 ksv_count += vrl_ksv_cnt;37 38 vrl_sz = (vrl_ksv_cnt * DRM_HDCP_KSV_LEN) + 1;39 buf += vrl_sz;40 parsed_bytes += vrl_sz;41 }42 43 /*44 * When vrls are not valid, ksvs are not considered.45 * Hence SRM will be discarded.46 */47 if (parsed_bytes != vrls_length)48 ksv_count = 0;49 50 return ksv_count;51}52 53static u32 drm_hdcp_get_revoked_ksvs(const u8 *buf, u8 **revoked_ksv_list,54 u32 vrls_length)55{56 u32 vrl_ksv_cnt, vrl_ksv_sz, vrl_idx = 0;57 u32 parsed_bytes = 0, ksv_count = 0;58 59 do {60 vrl_ksv_cnt = *buf;61 vrl_ksv_sz = vrl_ksv_cnt * DRM_HDCP_KSV_LEN;62 63 buf++;64 65 DRM_DEBUG("vrl: %d, Revoked KSVs: %d\n", vrl_idx++,66 vrl_ksv_cnt);67 memcpy((*revoked_ksv_list) + (ksv_count * DRM_HDCP_KSV_LEN),68 buf, vrl_ksv_sz);69 70 ksv_count += vrl_ksv_cnt;71 buf += vrl_ksv_sz;72 73 parsed_bytes += (vrl_ksv_sz + 1);74 } while (parsed_bytes < vrls_length);75 76 return ksv_count;77}78 79static inline u32 get_vrl_length(const u8 *buf)80{81 return drm_hdcp_be24_to_cpu(buf);82}83 84static int drm_hdcp_parse_hdcp1_srm(const u8 *buf, size_t count,85 u8 **revoked_ksv_list, u32 *revoked_ksv_cnt)86{87 struct hdcp_srm_header *header;88 u32 vrl_length, ksv_count;89 90 if (count < (sizeof(struct hdcp_srm_header) +91 DRM_HDCP_1_4_VRL_LENGTH_SIZE + DRM_HDCP_1_4_DCP_SIG_SIZE)) {92 DRM_ERROR("Invalid blob length\n");93 return -EINVAL;94 }95 96 header = (struct hdcp_srm_header *)buf;97 DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n",98 header->srm_id,99 be16_to_cpu(header->srm_version), header->srm_gen_no);100 101 WARN_ON(header->reserved);102 103 buf = buf + sizeof(*header);104 vrl_length = get_vrl_length(buf);105 if (count < (sizeof(struct hdcp_srm_header) + vrl_length) ||106 vrl_length < (DRM_HDCP_1_4_VRL_LENGTH_SIZE +107 DRM_HDCP_1_4_DCP_SIG_SIZE)) {108 DRM_ERROR("Invalid blob length or vrl length\n");109 return -EINVAL;110 }111 112 /* Length of the all vrls combined */113 vrl_length -= (DRM_HDCP_1_4_VRL_LENGTH_SIZE +114 DRM_HDCP_1_4_DCP_SIG_SIZE);115 116 if (!vrl_length) {117 DRM_ERROR("No vrl found\n");118 return -EINVAL;119 }120 121 buf += DRM_HDCP_1_4_VRL_LENGTH_SIZE;122 ksv_count = drm_hdcp_get_revoked_ksv_count(buf, vrl_length);123 if (!ksv_count) {124 DRM_DEBUG("Revoked KSV count is 0\n");125 return 0;126 }127 128 *revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN, GFP_KERNEL);129 if (!*revoked_ksv_list) {130 DRM_ERROR("Out of Memory\n");131 return -ENOMEM;132 }133 134 if (drm_hdcp_get_revoked_ksvs(buf, revoked_ksv_list,135 vrl_length) != ksv_count) {136 *revoked_ksv_cnt = 0;137 kfree(*revoked_ksv_list);138 return -EINVAL;139 }140 141 *revoked_ksv_cnt = ksv_count;142 return 0;143}144 145static int drm_hdcp_parse_hdcp2_srm(const u8 *buf, size_t count,146 u8 **revoked_ksv_list, u32 *revoked_ksv_cnt)147{148 struct hdcp_srm_header *header;149 u32 vrl_length, ksv_count, ksv_sz;150 151 if (count < (sizeof(struct hdcp_srm_header) +152 DRM_HDCP_2_VRL_LENGTH_SIZE + DRM_HDCP_2_DCP_SIG_SIZE)) {153 DRM_ERROR("Invalid blob length\n");154 return -EINVAL;155 }156 157 header = (struct hdcp_srm_header *)buf;158 DRM_DEBUG("SRM ID: 0x%x, SRM Ver: 0x%x, SRM Gen No: 0x%x\n",159 header->srm_id & DRM_HDCP_SRM_ID_MASK,160 be16_to_cpu(header->srm_version), header->srm_gen_no);161 162 if (header->reserved)163 return -EINVAL;164 165 buf = buf + sizeof(*header);166 vrl_length = get_vrl_length(buf);167 168 if (count < (sizeof(struct hdcp_srm_header) + vrl_length) ||169 vrl_length < (DRM_HDCP_2_VRL_LENGTH_SIZE +170 DRM_HDCP_2_DCP_SIG_SIZE)) {171 DRM_ERROR("Invalid blob length or vrl length\n");172 return -EINVAL;173 }174 175 /* Length of the all vrls combined */176 vrl_length -= (DRM_HDCP_2_VRL_LENGTH_SIZE +177 DRM_HDCP_2_DCP_SIG_SIZE);178 179 if (!vrl_length) {180 DRM_ERROR("No vrl found\n");181 return -EINVAL;182 }183 184 buf += DRM_HDCP_2_VRL_LENGTH_SIZE;185 ksv_count = (*buf << 2) | DRM_HDCP_2_KSV_COUNT_2_LSBITS(*(buf + 1));186 if (!ksv_count) {187 DRM_DEBUG("Revoked KSV count is 0\n");188 return 0;189 }190 191 *revoked_ksv_list = kcalloc(ksv_count, DRM_HDCP_KSV_LEN, GFP_KERNEL);192 if (!*revoked_ksv_list) {193 DRM_ERROR("Out of Memory\n");194 return -ENOMEM;195 }196 197 ksv_sz = ksv_count * DRM_HDCP_KSV_LEN;198 buf += DRM_HDCP_2_NO_OF_DEV_PLUS_RESERVED_SZ;199 200 DRM_DEBUG("Revoked KSVs: %d\n", ksv_count);201 memcpy(*revoked_ksv_list, buf, ksv_sz);202 203 *revoked_ksv_cnt = ksv_count;204 return 0;205}206 207static inline bool is_srm_version_hdcp1(const u8 *buf)208{209 return *buf == (u8)(DRM_HDCP_1_4_SRM_ID << 4);210}211 212static inline bool is_srm_version_hdcp2(const u8 *buf)213{214 return *buf == (u8)(DRM_HDCP_2_SRM_ID << 4 | DRM_HDCP_2_INDICATOR);215}216 217static int drm_hdcp_srm_update(const u8 *buf, size_t count,218 u8 **revoked_ksv_list, u32 *revoked_ksv_cnt)219{220 if (count < sizeof(struct hdcp_srm_header))221 return -EINVAL;222 223 if (is_srm_version_hdcp1(buf))224 return drm_hdcp_parse_hdcp1_srm(buf, count, revoked_ksv_list,225 revoked_ksv_cnt);226 else if (is_srm_version_hdcp2(buf))227 return drm_hdcp_parse_hdcp2_srm(buf, count, revoked_ksv_list,228 revoked_ksv_cnt);229 else230 return -EINVAL;231}232 233static int drm_hdcp_request_srm(struct drm_device *drm_dev,234 u8 **revoked_ksv_list, u32 *revoked_ksv_cnt)235{236 char fw_name[36] = "display_hdcp_srm.bin";237 const struct firmware *fw;238 int ret;239 240 ret = request_firmware_direct(&fw, (const char *)fw_name,241 drm_dev->dev);242 if (ret < 0) {243 *revoked_ksv_cnt = 0;244 *revoked_ksv_list = NULL;245 ret = 0;246 goto exit;247 }248 249 if (fw->size && fw->data)250 ret = drm_hdcp_srm_update(fw->data, fw->size, revoked_ksv_list,251 revoked_ksv_cnt);252 253exit:254 release_firmware(fw);255 return ret;256}257 258/**259 * drm_hdcp_check_ksvs_revoked - Check the revoked status of the IDs260 *261 * @drm_dev: drm_device for which HDCP revocation check is requested262 * @ksvs: List of KSVs (HDCP receiver IDs)263 * @ksv_count: KSV count passed in through @ksvs264 *265 * This function reads the HDCP System renewability Message(SRM Table)266 * from userspace as a firmware and parses it for the revoked HDCP267 * KSVs(Receiver IDs) detected by DCP LLC. Once the revoked KSVs are known,268 * revoked state of the KSVs in the list passed in by display drivers are269 * decided and response is sent.270 *271 * SRM should be presented in the name of "display_hdcp_srm.bin".272 *273 * Format of the SRM table, that userspace needs to write into the binary file,274 * is defined at:275 * 1. Renewability chapter on 55th page of HDCP 1.4 specification276 * https://www.digital-cp.com/sites/default/files/specifications/HDCP%20Specification%20Rev1_4_Secure.pdf277 * 2. Renewability chapter on 63rd page of HDCP 2.2 specification278 * https://www.digital-cp.com/sites/default/files/specifications/HDCP%20on%20HDMI%20Specification%20Rev2_2_Final1.pdf279 *280 * Returns:281 * Count of the revoked KSVs or -ve error number in case of the failure.282 */283int drm_hdcp_check_ksvs_revoked(struct drm_device *drm_dev, u8 *ksvs,284 u32 ksv_count)285{286 u32 revoked_ksv_cnt = 0, i, j;287 u8 *revoked_ksv_list = NULL;288 int ret = 0;289 290 ret = drm_hdcp_request_srm(drm_dev, &revoked_ksv_list,291 &revoked_ksv_cnt);292 if (ret)293 return ret;294 295 /* revoked_ksv_cnt will be zero when above function failed */296 for (i = 0; i < revoked_ksv_cnt; i++)297 for (j = 0; j < ksv_count; j++)298 if (!memcmp(&ksvs[j * DRM_HDCP_KSV_LEN],299 &revoked_ksv_list[i * DRM_HDCP_KSV_LEN],300 DRM_HDCP_KSV_LEN)) {301 DRM_DEBUG("Revoked KSV is ");302 drm_hdcp_print_ksv(&ksvs[j * DRM_HDCP_KSV_LEN]);303 ret++;304 }305 306 kfree(revoked_ksv_list);307 return ret;308}309EXPORT_SYMBOL_GPL(drm_hdcp_check_ksvs_revoked);310 311static struct drm_prop_enum_list drm_cp_enum_list[] = {312 { DRM_MODE_CONTENT_PROTECTION_UNDESIRED, "Undesired" },313 { DRM_MODE_CONTENT_PROTECTION_DESIRED, "Desired" },314 { DRM_MODE_CONTENT_PROTECTION_ENABLED, "Enabled" },315};316DRM_ENUM_NAME_FN(drm_get_content_protection_name, drm_cp_enum_list)317 318static struct drm_prop_enum_list drm_hdcp_content_type_enum_list[] = {319 { DRM_MODE_HDCP_CONTENT_TYPE0, "HDCP Type0" },320 { DRM_MODE_HDCP_CONTENT_TYPE1, "HDCP Type1" },321};322DRM_ENUM_NAME_FN(drm_get_hdcp_content_type_name,323 drm_hdcp_content_type_enum_list)324 325/**326 * drm_connector_attach_content_protection_property - attach content protection327 * property328 *329 * @connector: connector to attach CP property on.330 * @hdcp_content_type: is HDCP Content Type property needed for connector331 *332 * This is used to add support for content protection on select connectors.333 * Content Protection is intentionally vague to allow for different underlying334 * technologies, however it is most implemented by HDCP.335 *336 * When hdcp_content_type is true enum property called HDCP Content Type is337 * created (if it is not already) and attached to the connector.338 *339 * This property is used for sending the protected content's stream type340 * from userspace to kernel on selected connectors. Protected content provider341 * will decide their type of their content and declare the same to kernel.342 *343 * Content type will be used during the HDCP 2.2 authentication.344 * Content type will be set to &drm_connector_state.hdcp_content_type.345 *346 * The content protection will be set to &drm_connector_state.content_protection347 *348 * When kernel triggered content protection state change like DESIRED->ENABLED349 * and ENABLED->DESIRED, will use drm_hdcp_update_content_protection() to update350 * the content protection state of a connector.351 *352 * Returns:353 * Zero on success, negative errno on failure.354 */355int drm_connector_attach_content_protection_property(356 struct drm_connector *connector, bool hdcp_content_type)357{358 struct drm_device *dev = connector->dev;359 struct drm_property *prop =360 dev->mode_config.content_protection_property;361 362 if (!prop)363 prop = drm_property_create_enum(dev, 0, "Content Protection",364 drm_cp_enum_list,365 ARRAY_SIZE(drm_cp_enum_list));366 if (!prop)367 return -ENOMEM;368 369 drm_object_attach_property(&connector->base, prop,370 DRM_MODE_CONTENT_PROTECTION_UNDESIRED);371 dev->mode_config.content_protection_property = prop;372 373 if (!hdcp_content_type)374 return 0;375 376 prop = dev->mode_config.hdcp_content_type_property;377 if (!prop)378 prop = drm_property_create_enum(dev, 0, "HDCP Content Type",379 drm_hdcp_content_type_enum_list,380 ARRAY_SIZE(381 drm_hdcp_content_type_enum_list));382 if (!prop)383 return -ENOMEM;384 385 drm_object_attach_property(&connector->base, prop,386 DRM_MODE_HDCP_CONTENT_TYPE0);387 dev->mode_config.hdcp_content_type_property = prop;388 389 return 0;390}391EXPORT_SYMBOL(drm_connector_attach_content_protection_property);392 393/**394 * drm_hdcp_update_content_protection - Updates the content protection state395 * of a connector396 *397 * @connector: drm_connector on which content protection state needs an update398 * @val: New state of the content protection property399 *400 * This function can be used by display drivers, to update the kernel triggered401 * content protection state changes of a drm_connector such as DESIRED->ENABLED402 * and ENABLED->DESIRED. No uevent for DESIRED->UNDESIRED or ENABLED->UNDESIRED,403 * as userspace is triggering such state change and kernel performs it without404 * fail.This function update the new state of the property into the connector's405 * state and generate an uevent to notify the userspace.406 */407void drm_hdcp_update_content_protection(struct drm_connector *connector,408 u64 val)409{410 struct drm_device *dev = connector->dev;411 struct drm_connector_state *state = connector->state;412 413 WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));414 if (state->content_protection == val)415 return;416 417 state->content_protection = val;418 drm_sysfs_connector_property_event(connector,419 dev->mode_config.content_protection_property);420}421EXPORT_SYMBOL(drm_hdcp_update_content_protection);422