/* * Copyright 2014 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #define LOG_TAG "TrustyKeymaster" #include #include #include #include #include #include #include #include #include #include #include #include #include #include "keymaster_ipc.h" #include "trusty_keymaster_device.h" #include "trusty_keymaster_ipc.h" const uint32_t RECV_BUF_SIZE = PAGE_SIZE; const uint32_t SEND_BUF_SIZE = (PAGE_SIZE - sizeof(struct keymaster_message) - 16 /* tipc header */); const size_t kMaximumAttestationChallengeLength = 128; const size_t kMaximumFinishInputLength = 2048; namespace keymaster { static keymaster_error_t translate_error(int err) { switch (err) { case 0: return KM_ERROR_OK; case -EPERM: case -EACCES: return KM_ERROR_SECURE_HW_ACCESS_DENIED; case -ECANCELED: return KM_ERROR_OPERATION_CANCELLED; case -ENODEV: return KM_ERROR_UNIMPLEMENTED; case -ENOMEM: return KM_ERROR_MEMORY_ALLOCATION_FAILED; case -EBUSY: return KM_ERROR_SECURE_HW_BUSY; case -EIO: return KM_ERROR_SECURE_HW_COMMUNICATION_FAILED; case -EOVERFLOW: return KM_ERROR_INVALID_INPUT_LENGTH; default: return KM_ERROR_UNKNOWN_ERROR; } } TrustyKeymasterDevice::TrustyKeymasterDevice(const hw_module_t* module) { static_assert(std::is_standard_layout::value, "TrustyKeymasterDevice must be standard layout"); static_assert(offsetof(TrustyKeymasterDevice, device_) == 0, "device_ must be the first member of TrustyKeymasterDevice"); static_assert(offsetof(TrustyKeymasterDevice, device_.common) == 0, "common must be the first member of keymaster2_device"); ALOGI("Creating device"); ALOGD("Device address: %p", this); device_ = {}; device_.common.tag = HARDWARE_DEVICE_TAG; device_.common.version = 1; device_.common.module = const_cast(module); device_.common.close = close_device; device_.flags = KEYMASTER_SUPPORTS_EC; device_.configure = configure; device_.add_rng_entropy = add_rng_entropy; device_.generate_key = generate_key; device_.get_key_characteristics = get_key_characteristics; device_.import_key = import_key; device_.export_key = export_key; device_.attest_key = attest_key; device_.upgrade_key = upgrade_key; device_.delete_key = nullptr; device_.delete_all_keys = nullptr; device_.begin = begin; device_.update = update; device_.finish = finish; device_.abort = abort; int rc = trusty_keymaster_connect(); error_ = translate_error(rc); if (rc < 0) { ALOGE("failed to connect to keymaster (%d)", rc); return; } GetVersionRequest version_request; GetVersionResponse version_response; error_ = Send(KM_GET_VERSION, version_request, &version_response); if (error_ == KM_ERROR_INVALID_ARGUMENT || error_ == KM_ERROR_UNIMPLEMENTED) { ALOGE("\"Bad parameters\" error on GetVersion call. Version 0 is not supported."); error_ = KM_ERROR_VERSION_MISMATCH; return; } message_version_ = MessageVersion(version_response.major_ver, version_response.minor_ver, version_response.subminor_ver); if (message_version_ < 0) { // Can't translate version? Keymaster implementation must be newer. ALOGE("Keymaster version %d.%d.%d not supported.", version_response.major_ver, version_response.minor_ver, version_response.subminor_ver); error_ = KM_ERROR_VERSION_MISMATCH; } } TrustyKeymasterDevice::~TrustyKeymasterDevice() { trusty_keymaster_disconnect(); } namespace { // Allocates a new buffer with malloc and copies the contents of |buffer| to it. Caller takes // ownership of the returned buffer. uint8_t* DuplicateBuffer(const uint8_t* buffer, size_t size) { uint8_t* tmp = reinterpret_cast(malloc(size)); if (tmp) { memcpy(tmp, buffer, size); } return tmp; } template void AddClientAndAppData(const keymaster_blob_t* client_id, const keymaster_blob_t* app_data, RequestType* request) { request->additional_params.Clear(); if (client_id) { request->additional_params.push_back(TAG_APPLICATION_ID, *client_id); } if (app_data) { request->additional_params.push_back(TAG_APPLICATION_DATA, *app_data); } } } // unnamed namespace keymaster_error_t TrustyKeymasterDevice::configure(const keymaster_key_param_set_t* params) { ALOGD("Device received configure\n"); if (error_ != KM_ERROR_OK) { return error_; } if (!params) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } AuthorizationSet params_copy(*params); ConfigureRequest request; if (!params_copy.GetTagValue(TAG_OS_VERSION, &request.os_version) || !params_copy.GetTagValue(TAG_OS_PATCHLEVEL, &request.os_patchlevel)) { ALOGD("Configuration parameters must contain OS version and patch level"); return KM_ERROR_INVALID_ARGUMENT; } ConfigureResponse response; keymaster_error_t err = Send(KM_CONFIGURE, request, &response); if (err != KM_ERROR_OK) { return err; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::add_rng_entropy(const uint8_t* data, size_t data_length) { ALOGD("Device received add_rng_entropy"); if (error_ != KM_ERROR_OK) { return error_; } AddEntropyRequest request; request.random_data.Reinitialize(data, data_length); AddEntropyResponse response; return Send(KM_ADD_RNG_ENTROPY, request, &response); } keymaster_error_t TrustyKeymasterDevice::generate_key( const keymaster_key_param_set_t* params, keymaster_key_blob_t* key_blob, keymaster_key_characteristics_t* characteristics) { ALOGD("Device received generate_key"); if (error_ != KM_ERROR_OK) { return error_; } if (!params) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!key_blob) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } GenerateKeyRequest request(message_version_); request.key_description.Reinitialize(*params); request.key_description.push_back(TAG_CREATION_DATETIME, java_time(time(NULL))); GenerateKeyResponse response(message_version_); keymaster_error_t err = Send(KM_GENERATE_KEY, request, &response); if (err != KM_ERROR_OK) { return err; } key_blob->key_material_size = response.key_blob.key_material_size; key_blob->key_material = DuplicateBuffer(response.key_blob.key_material, response.key_blob.key_material_size); if (!key_blob->key_material) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } if (characteristics) { response.enforced.CopyToParamSet(&characteristics->hw_enforced); response.unenforced.CopyToParamSet(&characteristics->sw_enforced); } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::get_key_characteristics( const keymaster_key_blob_t* key_blob, const keymaster_blob_t* client_id, const keymaster_blob_t* app_data, keymaster_key_characteristics_t* characteristics) { ALOGD("Device received get_key_characteristics"); if (error_ != KM_ERROR_OK) { return error_; } if (!key_blob || !key_blob->key_material) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!characteristics) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } GetKeyCharacteristicsRequest request; request.SetKeyMaterial(*key_blob); AddClientAndAppData(client_id, app_data, &request); GetKeyCharacteristicsResponse response; keymaster_error_t err = Send(KM_GET_KEY_CHARACTERISTICS, request, &response); if (err != KM_ERROR_OK) { return err; } response.enforced.CopyToParamSet(&characteristics->hw_enforced); response.unenforced.CopyToParamSet(&characteristics->sw_enforced); return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::import_key( const keymaster_key_param_set_t* params, keymaster_key_format_t key_format, const keymaster_blob_t* key_data, keymaster_key_blob_t* key_blob, keymaster_key_characteristics_t* characteristics) { ALOGD("Device received import_key"); if (error_ != KM_ERROR_OK) { return error_; } if (!params || !key_data) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!key_blob) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } ImportKeyRequest request(message_version_); request.key_description.Reinitialize(*params); request.key_description.push_back(TAG_CREATION_DATETIME, java_time(time(NULL))); request.key_format = key_format; request.SetKeyMaterial(key_data->data, key_data->data_length); ImportKeyResponse response(message_version_); keymaster_error_t err = Send(KM_IMPORT_KEY, request, &response); if (err != KM_ERROR_OK) { return err; } key_blob->key_material_size = response.key_blob.key_material_size; key_blob->key_material = DuplicateBuffer(response.key_blob.key_material, response.key_blob.key_material_size); if (!key_blob->key_material) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } if (characteristics) { response.enforced.CopyToParamSet(&characteristics->hw_enforced); response.unenforced.CopyToParamSet(&characteristics->sw_enforced); } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::export_key(keymaster_key_format_t export_format, const keymaster_key_blob_t* key_to_export, const keymaster_blob_t* client_id, const keymaster_blob_t* app_data, keymaster_blob_t* export_data) { ALOGD("Device received export_key"); if (error_ != KM_ERROR_OK) { return error_; } if (!key_to_export || !key_to_export->key_material) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!export_data) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } export_data->data = nullptr; export_data->data_length = 0; ExportKeyRequest request(message_version_); request.key_format = export_format; request.SetKeyMaterial(*key_to_export); AddClientAndAppData(client_id, app_data, &request); ExportKeyResponse response(message_version_); keymaster_error_t err = Send(KM_EXPORT_KEY, request, &response); if (err != KM_ERROR_OK) { return err; } export_data->data_length = response.key_data_length; export_data->data = DuplicateBuffer(response.key_data, response.key_data_length); if (!export_data->data) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::attest_key(const keymaster_key_blob_t* key_to_attest, const keymaster_key_param_set_t* attest_params, keymaster_cert_chain_t* cert_chain) { ALOGD("Device received attest_key"); if (error_ != KM_ERROR_OK) { return error_; } if (!key_to_attest || !attest_params) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!cert_chain) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } cert_chain->entry_count = 0; cert_chain->entries = nullptr; AttestKeyRequest request; request.SetKeyMaterial(*key_to_attest); request.attest_params.Reinitialize(*attest_params); keymaster_blob_t attestation_challenge = {}; request.attest_params.GetTagValue(TAG_ATTESTATION_CHALLENGE, &attestation_challenge); if (attestation_challenge.data_length > kMaximumAttestationChallengeLength) { ALOGE("%zu-byte attestation challenge; only %zu bytes allowed", attestation_challenge.data_length, kMaximumAttestationChallengeLength); return KM_ERROR_INVALID_INPUT_LENGTH; } AttestKeyResponse response; keymaster_error_t err = Send(KM_ATTEST_KEY, request, &response); if (err != KM_ERROR_OK) { return err; } // Allocate and clear storage for cert_chain. keymaster_cert_chain_t& rsp_chain = response.certificate_chain; cert_chain->entries = reinterpret_cast( malloc(rsp_chain.entry_count * sizeof(*cert_chain->entries))); if (!cert_chain->entries) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } cert_chain->entry_count = rsp_chain.entry_count; for (keymaster_blob_t& entry : array_range(cert_chain->entries, cert_chain->entry_count)) { entry = {}; } // Copy cert_chain contents size_t i = 0; for (keymaster_blob_t& entry : array_range(rsp_chain.entries, rsp_chain.entry_count)) { cert_chain->entries[i].data = DuplicateBuffer(entry.data, entry.data_length); if (!cert_chain->entries[i].data) { keymaster_free_cert_chain(cert_chain); return KM_ERROR_MEMORY_ALLOCATION_FAILED; } cert_chain->entries[i].data_length = entry.data_length; ++i; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::upgrade_key(const keymaster_key_blob_t* key_to_upgrade, const keymaster_key_param_set_t* upgrade_params, keymaster_key_blob_t* upgraded_key) { ALOGD("Device received upgrade_key"); if (error_ != KM_ERROR_OK) { return error_; } if (!key_to_upgrade || !upgrade_params) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!upgraded_key) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } UpgradeKeyRequest request; request.SetKeyMaterial(*key_to_upgrade); request.upgrade_params.Reinitialize(*upgrade_params); UpgradeKeyResponse response; keymaster_error_t err = Send(KM_UPGRADE_KEY, request, &response); if (err != KM_ERROR_OK) { return err; } upgraded_key->key_material_size = response.upgraded_key.key_material_size; upgraded_key->key_material = DuplicateBuffer(response.upgraded_key.key_material, response.upgraded_key.key_material_size); if (!upgraded_key->key_material) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::begin(keymaster_purpose_t purpose, const keymaster_key_blob_t* key, const keymaster_key_param_set_t* in_params, keymaster_key_param_set_t* out_params, keymaster_operation_handle_t* operation_handle) { ALOGD("Device received begin"); if (error_ != KM_ERROR_OK) { return error_; } if (!key || !key->key_material) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!operation_handle) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } if (out_params) { *out_params = {}; } BeginOperationRequest request; request.purpose = purpose; request.SetKeyMaterial(*key); request.additional_params.Reinitialize(*in_params); BeginOperationResponse response; keymaster_error_t err = Send(KM_BEGIN_OPERATION, request, &response); if (err != KM_ERROR_OK) { return err; } if (response.output_params.size() > 0) { if (out_params) { response.output_params.CopyToParamSet(out_params); } else { return KM_ERROR_OUTPUT_PARAMETER_NULL; } } *operation_handle = response.op_handle; return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::update(keymaster_operation_handle_t operation_handle, const keymaster_key_param_set_t* in_params, const keymaster_blob_t* input, size_t* input_consumed, keymaster_key_param_set_t* out_params, keymaster_blob_t* output) { ALOGD("Device received update"); if (error_ != KM_ERROR_OK) { return error_; } if (!input) { return KM_ERROR_UNEXPECTED_NULL_POINTER; } if (!input_consumed) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } if (out_params) { *out_params = {}; } if (output) { *output = {}; } UpdateOperationRequest request; request.op_handle = operation_handle; if (in_params) { request.additional_params.Reinitialize(*in_params); } if (input && input->data_length > 0) { size_t max_input_size = SEND_BUF_SIZE - request.SerializedSize(); request.input.Reinitialize(input->data, std::min(input->data_length, max_input_size)); } UpdateOperationResponse response; keymaster_error_t err = Send(KM_UPDATE_OPERATION, request, &response); if (err != KM_ERROR_OK) { return err; } if (response.output_params.size() > 0) { if (out_params) { response.output_params.CopyToParamSet(out_params); } else { return KM_ERROR_OUTPUT_PARAMETER_NULL; } } *input_consumed = response.input_consumed; if (output) { output->data_length = response.output.available_read(); output->data = DuplicateBuffer(response.output.peek_read(), output->data_length); if (!output->data) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } } else if (response.output.available_read() > 0) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::finish(keymaster_operation_handle_t operation_handle, const keymaster_key_param_set_t* in_params, const keymaster_blob_t* input, const keymaster_blob_t* signature, keymaster_key_param_set_t* out_params, keymaster_blob_t* output) { ALOGD("Device received finish"); if (error_ != KM_ERROR_OK) { return error_; } if (input && input->data_length > kMaximumFinishInputLength) { return KM_ERROR_INVALID_ARGUMENT; } if (out_params) { *out_params = {}; } if (output) { *output = {}; } FinishOperationRequest request; request.op_handle = operation_handle; if (signature && signature->data && signature->data_length > 0) { request.signature.Reinitialize(signature->data, signature->data_length); } if (input && input->data && input->data_length) { request.input.Reinitialize(input->data, input->data_length); } if (in_params) { request.additional_params.Reinitialize(*in_params); } FinishOperationResponse response; keymaster_error_t err = Send(KM_FINISH_OPERATION, request, &response); if (err != KM_ERROR_OK) { return err; } if (response.output_params.size() > 0) { if (out_params) { response.output_params.CopyToParamSet(out_params); } else { return KM_ERROR_OUTPUT_PARAMETER_NULL; } } if (output) { output->data_length = response.output.available_read(); output->data = DuplicateBuffer(response.output.peek_read(), output->data_length); if (!output->data) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } } else if (response.output.available_read() > 0) { return KM_ERROR_OUTPUT_PARAMETER_NULL; } return KM_ERROR_OK; } keymaster_error_t TrustyKeymasterDevice::abort(keymaster_operation_handle_t operation_handle) { ALOGD("Device received abort"); if (error_ != KM_ERROR_OK) { return error_; } AbortOperationRequest request; request.op_handle = operation_handle; AbortOperationResponse response; return Send(KM_ABORT_OPERATION, request, &response); } hw_device_t* TrustyKeymasterDevice::hw_device() { return &device_.common; } static inline TrustyKeymasterDevice* convert_device(const keymaster2_device_t* dev) { return reinterpret_cast(const_cast(dev)); } /* static */ int TrustyKeymasterDevice::close_device(hw_device_t* dev) { delete reinterpret_cast(dev); return 0; } /* static */ keymaster_error_t TrustyKeymasterDevice::configure(const keymaster2_device_t* dev, const keymaster_key_param_set_t* params) { return convert_device(dev)->configure(params); } /* static */ keymaster_error_t TrustyKeymasterDevice::add_rng_entropy(const keymaster2_device_t* dev, const uint8_t* data, size_t data_length) { return convert_device(dev)->add_rng_entropy(data, data_length); } /* static */ keymaster_error_t TrustyKeymasterDevice::generate_key( const keymaster2_device_t* dev, const keymaster_key_param_set_t* params, keymaster_key_blob_t* key_blob, keymaster_key_characteristics_t* characteristics) { return convert_device(dev)->generate_key(params, key_blob, characteristics); } /* static */ keymaster_error_t TrustyKeymasterDevice::get_key_characteristics( const keymaster2_device_t* dev, const keymaster_key_blob_t* key_blob, const keymaster_blob_t* client_id, const keymaster_blob_t* app_data, keymaster_key_characteristics_t* characteristics) { return convert_device(dev)->get_key_characteristics(key_blob, client_id, app_data, characteristics); } /* static */ keymaster_error_t TrustyKeymasterDevice::import_key( const keymaster2_device_t* dev, const keymaster_key_param_set_t* params, keymaster_key_format_t key_format, const keymaster_blob_t* key_data, keymaster_key_blob_t* key_blob, keymaster_key_characteristics_t* characteristics) { return convert_device(dev)->import_key(params, key_format, key_data, key_blob, characteristics); } /* static */ keymaster_error_t TrustyKeymasterDevice::export_key(const keymaster2_device_t* dev, keymaster_key_format_t export_format, const keymaster_key_blob_t* key_to_export, const keymaster_blob_t* client_id, const keymaster_blob_t* app_data, keymaster_blob_t* export_data) { return convert_device(dev)->export_key(export_format, key_to_export, client_id, app_data, export_data); } /* static */ keymaster_error_t TrustyKeymasterDevice::attest_key(const keymaster2_device_t* dev, const keymaster_key_blob_t* key_to_attest, const keymaster_key_param_set_t* attest_params, keymaster_cert_chain_t* cert_chain) { return convert_device(dev)->attest_key(key_to_attest, attest_params, cert_chain); } /* static */ keymaster_error_t TrustyKeymasterDevice::upgrade_key(const keymaster2_device_t* dev, const keymaster_key_blob_t* key_to_upgrade, const keymaster_key_param_set_t* upgrade_params, keymaster_key_blob_t* upgraded_key) { return convert_device(dev)->upgrade_key(key_to_upgrade, upgrade_params, upgraded_key); } /* static */ keymaster_error_t TrustyKeymasterDevice::begin(const keymaster2_device_t* dev, keymaster_purpose_t purpose, const keymaster_key_blob_t* key, const keymaster_key_param_set_t* in_params, keymaster_key_param_set_t* out_params, keymaster_operation_handle_t* operation_handle) { return convert_device(dev)->begin(purpose, key, in_params, out_params, operation_handle); } /* static */ keymaster_error_t TrustyKeymasterDevice::update( const keymaster2_device_t* dev, keymaster_operation_handle_t operation_handle, const keymaster_key_param_set_t* in_params, const keymaster_blob_t* input, size_t* input_consumed, keymaster_key_param_set_t* out_params, keymaster_blob_t* output) { return convert_device(dev)->update(operation_handle, in_params, input, input_consumed, out_params, output); } /* static */ keymaster_error_t TrustyKeymasterDevice::finish(const keymaster2_device_t* dev, keymaster_operation_handle_t operation_handle, const keymaster_key_param_set_t* in_params, const keymaster_blob_t* input, const keymaster_blob_t* signature, keymaster_key_param_set_t* out_params, keymaster_blob_t* output) { return convert_device(dev)->finish(operation_handle, in_params, input, signature, out_params, output); } /* static */ keymaster_error_t TrustyKeymasterDevice::abort(const keymaster2_device_t* dev, keymaster_operation_handle_t operation_handle) { return convert_device(dev)->abort(operation_handle); } keymaster_error_t TrustyKeymasterDevice::Send(uint32_t command, const Serializable& req, KeymasterResponse* rsp) { uint32_t req_size = req.SerializedSize(); if (req_size > SEND_BUF_SIZE) { return KM_ERROR_MEMORY_ALLOCATION_FAILED; } uint8_t send_buf[SEND_BUF_SIZE]; Eraser send_buf_eraser(send_buf, SEND_BUF_SIZE); req.Serialize(send_buf, send_buf + req_size); // Send it uint8_t recv_buf[RECV_BUF_SIZE]; Eraser recv_buf_eraser(recv_buf, RECV_BUF_SIZE); uint32_t rsp_size = RECV_BUF_SIZE; ALOGV("Sending %d byte request\n", (int)req.SerializedSize()); int rc = trusty_keymaster_call(command, send_buf, req_size, recv_buf, &rsp_size); if (rc < 0) { ALOGE("tipc error: %d\n", rc); // TODO(swillden): Distinguish permanent from transient errors and set error_ appropriately. return translate_error(rc); } else { ALOGV("Received %d byte response\n", rsp_size); } const keymaster_message* msg = (keymaster_message*)recv_buf; const uint8_t* p = msg->payload; if (!rsp->Deserialize(&p, p + rsp_size)) { ALOGE("Error deserializing response of size %d\n", (int)rsp_size); return KM_ERROR_UNKNOWN_ERROR; } else if (rsp->error != KM_ERROR_OK) { ALOGE("Response of size %d contained error code %d\n", (int)rsp_size, (int)rsp->error); return rsp->error; } return rsp->error; } } // namespace keymaster