diff options
Diffstat (limited to 'trusty/keymaster/trusty_keymaster_device.cpp')
| -rw-r--r-- | trusty/keymaster/trusty_keymaster_device.cpp | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/trusty/keymaster/trusty_keymaster_device.cpp b/trusty/keymaster/trusty_keymaster_device.cpp new file mode 100644 index 000000000..069b4fedb --- /dev/null +++ b/trusty/keymaster/trusty_keymaster_device.cpp @@ -0,0 +1,536 @@ +/* + * 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. + */ + +#include "trusty_keymaster_device.h" + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <stddef.h> + +#include <type_traits> + +#include <openssl/evp.h> +#include <openssl/x509.h> + +#define LOG_TAG "TrustyKeymaster" +#include <cutils/log.h> +#include <hardware/keymaster0.h> + +#include <keymaster/authorization_set.h> + +#include "trusty_keymaster_ipc.h" +#include "keymaster_ipc.h" + +const uint32_t SEND_BUF_SIZE = 8192; +const uint32_t RECV_BUF_SIZE = 8192; + +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<TrustyKeymasterDevice>::value, + "TrustyKeymasterDevice must be standard layout"); + static_assert(offsetof(TrustyKeymasterDevice, device_) == 0, + "device_ must be the first member of KeymasterOpenSsl"); + static_assert(offsetof(TrustyKeymasterDevice, device_.common) == 0, + "common must be the first member of keymaster_device"); + + ALOGI("Creating device"); + ALOGD("Device address: %p", this); + + memset(&device_, 0, sizeof(device_)); + + device_.common.tag = HARDWARE_DEVICE_TAG; + device_.common.version = 1; + device_.common.module = const_cast<hw_module_t*>(module); + device_.common.close = close_device; + + device_.flags = KEYMASTER_BLOBS_ARE_STANDALONE | KEYMASTER_SUPPORTS_EC; + + device_.generate_keypair = generate_keypair; + device_.import_keypair = import_keypair; + device_.get_keypair_public = get_keypair_public; + device_.delete_keypair = NULL; + device_.delete_all = NULL; + device_.sign_data = sign_data; + device_.verify_data = verify_data; + + device_.context = NULL; + + 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(version_request, &version_response); + if (error_ == KM_ERROR_INVALID_ARGUMENT || error_ == KM_ERROR_UNIMPLEMENTED) { + ALOGI("\"Bad parameters\" error on GetVersion call. Assuming version 0."); + message_version_ = 0; + error_ = KM_ERROR_OK; + } + 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(); +} + +const uint64_t HUNDRED_YEARS = 1000LL * 60 * 60 * 24 * 365 * 100; + +int TrustyKeymasterDevice::generate_keypair(const keymaster_keypair_t key_type, + const void* key_params, uint8_t** key_blob, + size_t* key_blob_length) { + ALOGD("Device received generate_keypair"); + + if (error_ != KM_ERROR_OK) + return error_; + + GenerateKeyRequest req(message_version_); + StoreNewKeyParams(&req.key_description); + + switch (key_type) { + case TYPE_RSA: { + req.key_description.push_back(TAG_ALGORITHM, KM_ALGORITHM_RSA); + const keymaster_rsa_keygen_params_t* rsa_params = + static_cast<const keymaster_rsa_keygen_params_t*>(key_params); + ALOGD("Generating RSA pair, modulus size: %u, public exponent: %lu", + rsa_params->modulus_size, rsa_params->public_exponent); + req.key_description.push_back(TAG_KEY_SIZE, rsa_params->modulus_size); + req.key_description.push_back(TAG_RSA_PUBLIC_EXPONENT, rsa_params->public_exponent); + break; + } + + case TYPE_EC: { + req.key_description.push_back(TAG_ALGORITHM, KM_ALGORITHM_EC); + const keymaster_ec_keygen_params_t* ec_params = + static_cast<const keymaster_ec_keygen_params_t*>(key_params); + ALOGD("Generating ECDSA pair, key size: %u", ec_params->field_size); + req.key_description.push_back(TAG_KEY_SIZE, ec_params->field_size); + break; + } + default: + ALOGD("Received request for unsuported key type %d", key_type); + return KM_ERROR_UNSUPPORTED_ALGORITHM; + } + + GenerateKeyResponse rsp(message_version_); + ALOGD("Sending generate request"); + keymaster_error_t err = Send(req, &rsp); + if (err != KM_ERROR_OK) { + ALOGE("Got error %d from send", err); + return err; + } + + *key_blob_length = rsp.key_blob.key_material_size; + *key_blob = static_cast<uint8_t*>(malloc(*key_blob_length)); + memcpy(*key_blob, rsp.key_blob.key_material, *key_blob_length); + ALOGD("Returning %d bytes in key blob\n", (int)*key_blob_length); + + return KM_ERROR_OK; +} + +struct EVP_PKEY_Delete { + void operator()(EVP_PKEY* p) const { EVP_PKEY_free(p); } +}; + +struct PKCS8_PRIV_KEY_INFO_Delete { + void operator()(PKCS8_PRIV_KEY_INFO* p) const { PKCS8_PRIV_KEY_INFO_free(p); } +}; + +int TrustyKeymasterDevice::import_keypair(const uint8_t* key, const size_t key_length, + uint8_t** key_blob, size_t* key_blob_length) { + ALOGD("Device received import_keypair"); + if (error_ != KM_ERROR_OK) + return error_; + + if (!key) + return KM_ERROR_UNEXPECTED_NULL_POINTER; + + if (!key_blob || !key_blob_length) + return KM_ERROR_OUTPUT_PARAMETER_NULL; + + ImportKeyRequest request(message_version_); + StoreNewKeyParams(&request.key_description); + keymaster_algorithm_t algorithm; + keymaster_error_t err = GetPkcs8KeyAlgorithm(key, key_length, &algorithm); + if (err != KM_ERROR_OK) + return err; + request.key_description.push_back(TAG_ALGORITHM, algorithm); + + request.SetKeyMaterial(key, key_length); + request.key_format = KM_KEY_FORMAT_PKCS8; + ImportKeyResponse response(message_version_); + err = Send(request, &response); + if (err != KM_ERROR_OK) + return err; + + *key_blob_length = response.key_blob.key_material_size; + *key_blob = static_cast<uint8_t*>(malloc(*key_blob_length)); + memcpy(*key_blob, response.key_blob.key_material, *key_blob_length); + printf("Returning %d bytes in key blob\n", (int)*key_blob_length); + + return KM_ERROR_OK; +} + +keymaster_error_t TrustyKeymasterDevice::GetPkcs8KeyAlgorithm(const uint8_t* key, size_t key_length, + keymaster_algorithm_t* algorithm) { + if (key == NULL) { + ALOGE("No key specified for import"); + return KM_ERROR_UNEXPECTED_NULL_POINTER; + } + + UniquePtr<PKCS8_PRIV_KEY_INFO, PKCS8_PRIV_KEY_INFO_Delete> pkcs8( + d2i_PKCS8_PRIV_KEY_INFO(NULL, &key, key_length)); + if (pkcs8.get() == NULL) { + ALOGE("Could not parse PKCS8 key blob"); + return KM_ERROR_INVALID_KEY_BLOB; + } + + UniquePtr<EVP_PKEY, EVP_PKEY_Delete> pkey(EVP_PKCS82PKEY(pkcs8.get())); + if (pkey.get() == NULL) { + ALOGE("Could not extract key from PKCS8 key blob"); + return KM_ERROR_INVALID_KEY_BLOB; + } + + switch (EVP_PKEY_type(pkey->type)) { + case EVP_PKEY_RSA: + *algorithm = KM_ALGORITHM_RSA; + break; + case EVP_PKEY_EC: + *algorithm = KM_ALGORITHM_EC; + break; + default: + ALOGE("Unsupported algorithm %d", EVP_PKEY_type(pkey->type)); + return KM_ERROR_UNSUPPORTED_ALGORITHM; + } + + return KM_ERROR_OK; +} + +int TrustyKeymasterDevice::get_keypair_public(const uint8_t* key_blob, const size_t key_blob_length, + uint8_t** x509_data, size_t* x509_data_length) { + ALOGD("Device received get_keypair_public"); + if (error_ != KM_ERROR_OK) + return error_; + + ExportKeyRequest request(message_version_); + request.SetKeyMaterial(key_blob, key_blob_length); + request.key_format = KM_KEY_FORMAT_X509; + ExportKeyResponse response(message_version_); + keymaster_error_t err = Send(request, &response); + if (err != KM_ERROR_OK) + return err; + + *x509_data_length = response.key_data_length; + *x509_data = static_cast<uint8_t*>(malloc(*x509_data_length)); + memcpy(*x509_data, response.key_data, *x509_data_length); + printf("Returning %d bytes in x509 key\n", (int)*x509_data_length); + + return KM_ERROR_OK; +} + +int TrustyKeymasterDevice::sign_data(const void* signing_params, const uint8_t* key_blob, + const size_t key_blob_length, const uint8_t* data, + const size_t data_length, uint8_t** signed_data, + size_t* signed_data_length) { + ALOGD("Device received sign_data, %d", error_); + if (error_ != KM_ERROR_OK) + return error_; + + BeginOperationRequest begin_request(message_version_); + begin_request.purpose = KM_PURPOSE_SIGN; + begin_request.SetKeyMaterial(key_blob, key_blob_length); + keymaster_error_t err = StoreSigningParams(signing_params, key_blob, key_blob_length, + &begin_request.additional_params); + if (err != KM_ERROR_OK) { + ALOGE("Error extracting signing params: %d", err); + return err; + } + + BeginOperationResponse begin_response(message_version_); + ALOGD("Sending signing request begin"); + err = Send(begin_request, &begin_response); + if (err != KM_ERROR_OK) { + ALOGE("Error sending sign begin: %d", err); + return err; + } + + UpdateOperationRequest update_request(message_version_); + update_request.op_handle = begin_response.op_handle; + update_request.input.Reinitialize(data, data_length); + UpdateOperationResponse update_response(message_version_); + ALOGD("Sending signing request update"); + err = Send(update_request, &update_response); + if (err != KM_ERROR_OK) { + ALOGE("Error sending sign update: %d", err); + return err; + } + + FinishOperationRequest finish_request(message_version_); + finish_request.op_handle = begin_response.op_handle; + FinishOperationResponse finish_response(message_version_); + ALOGD("Sending signing request finish"); + err = Send(finish_request, &finish_response); + if (err != KM_ERROR_OK) { + ALOGE("Error sending sign finish: %d", err); + return err; + } + + *signed_data_length = finish_response.output.available_read(); + *signed_data = static_cast<uint8_t*>(malloc(*signed_data_length)); + if (!finish_response.output.read(*signed_data, *signed_data_length)) { + ALOGE("Error reading response data: %d", err); + return KM_ERROR_UNKNOWN_ERROR; + } + return KM_ERROR_OK; +} + +int TrustyKeymasterDevice::verify_data(const void* signing_params, const uint8_t* key_blob, + const size_t key_blob_length, const uint8_t* signed_data, + const size_t signed_data_length, const uint8_t* signature, + const size_t signature_length) { + ALOGD("Device received verify_data"); + if (error_ != KM_ERROR_OK) + return error_; + + BeginOperationRequest begin_request(message_version_); + begin_request.purpose = KM_PURPOSE_VERIFY; + begin_request.SetKeyMaterial(key_blob, key_blob_length); + keymaster_error_t err = StoreSigningParams(signing_params, key_blob, key_blob_length, + &begin_request.additional_params); + if (err != KM_ERROR_OK) + return err; + + BeginOperationResponse begin_response(message_version_); + err = Send(begin_request, &begin_response); + if (err != KM_ERROR_OK) + return err; + + UpdateOperationRequest update_request(message_version_); + update_request.op_handle = begin_response.op_handle; + update_request.input.Reinitialize(signed_data, signed_data_length); + UpdateOperationResponse update_response(message_version_); + err = Send(update_request, &update_response); + if (err != KM_ERROR_OK) + return err; + + FinishOperationRequest finish_request(message_version_); + finish_request.op_handle = begin_response.op_handle; + finish_request.signature.Reinitialize(signature, signature_length); + FinishOperationResponse finish_response(message_version_); + err = Send(finish_request, &finish_response); + if (err != KM_ERROR_OK) + return err; + return KM_ERROR_OK; +} + +hw_device_t* TrustyKeymasterDevice::hw_device() { + return &device_.common; +} + +static inline TrustyKeymasterDevice* convert_device(const keymaster0_device_t* dev) { + return reinterpret_cast<TrustyKeymasterDevice*>(const_cast<keymaster0_device_t*>(dev)); +} + +/* static */ +int TrustyKeymasterDevice::close_device(hw_device_t* dev) { + delete reinterpret_cast<TrustyKeymasterDevice*>(dev); + return 0; +} + +/* static */ +int TrustyKeymasterDevice::generate_keypair(const keymaster0_device_t* dev, + const keymaster_keypair_t key_type, + const void* key_params, uint8_t** keyBlob, + size_t* keyBlobLength) { + ALOGD("Generate keypair, sending to device: %p", convert_device(dev)); + return convert_device(dev)->generate_keypair(key_type, key_params, keyBlob, keyBlobLength); +} + +/* static */ +int TrustyKeymasterDevice::import_keypair(const keymaster0_device_t* dev, const uint8_t* key, + const size_t key_length, uint8_t** key_blob, + size_t* key_blob_length) { + return convert_device(dev)->import_keypair(key, key_length, key_blob, key_blob_length); +} + +/* static */ +int TrustyKeymasterDevice::get_keypair_public(const keymaster0_device_t* dev, + const uint8_t* key_blob, const size_t key_blob_length, + uint8_t** x509_data, size_t* x509_data_length) { + return convert_device(dev) + ->get_keypair_public(key_blob, key_blob_length, x509_data, x509_data_length); +} + +/* static */ +int TrustyKeymasterDevice::sign_data(const keymaster0_device_t* dev, const void* params, + const uint8_t* keyBlob, const size_t keyBlobLength, + const uint8_t* data, const size_t dataLength, + uint8_t** signedData, size_t* signedDataLength) { + return convert_device(dev) + ->sign_data(params, keyBlob, keyBlobLength, data, dataLength, signedData, signedDataLength); +} + +/* static */ +int TrustyKeymasterDevice::verify_data(const keymaster0_device_t* dev, const void* params, + const uint8_t* keyBlob, const size_t keyBlobLength, + const uint8_t* signedData, const size_t signedDataLength, + const uint8_t* signature, const size_t signatureLength) { + return convert_device(dev)->verify_data(params, keyBlob, keyBlobLength, signedData, + signedDataLength, signature, signatureLength); +} + +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; + printf("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; +} + +keymaster_error_t TrustyKeymasterDevice::StoreSigningParams(const void* signing_params, + const uint8_t* key_blob, + size_t key_blob_length, + AuthorizationSet* auth_set) { + uint8_t* pub_key_data; + size_t pub_key_data_length; + int err = get_keypair_public(&device_, key_blob, key_blob_length, &pub_key_data, + &pub_key_data_length); + if (err < 0) { + ALOGE("Error %d extracting public key to determine algorithm", err); + return KM_ERROR_INVALID_KEY_BLOB; + } + UniquePtr<uint8_t, Malloc_Delete> pub_key(pub_key_data); + + const uint8_t* p = pub_key_data; + UniquePtr<EVP_PKEY, EVP_PKEY_Delete> pkey( + d2i_PUBKEY(nullptr /* allocate new struct */, &p, pub_key_data_length)); + + switch (EVP_PKEY_type(pkey->type)) { + case EVP_PKEY_RSA: { + const keymaster_rsa_sign_params_t* rsa_params = + reinterpret_cast<const keymaster_rsa_sign_params_t*>(signing_params); + if (rsa_params->digest_type != DIGEST_NONE) + return KM_ERROR_UNSUPPORTED_DIGEST; + if (rsa_params->padding_type != PADDING_NONE) + return KM_ERROR_UNSUPPORTED_PADDING_MODE; + if (!auth_set->push_back(TAG_DIGEST, KM_DIGEST_NONE) || + !auth_set->push_back(TAG_PADDING, KM_PAD_NONE)) + return KM_ERROR_MEMORY_ALLOCATION_FAILED; + } break; + case EVP_PKEY_EC: { + const keymaster_ec_sign_params_t* ecdsa_params = + reinterpret_cast<const keymaster_ec_sign_params_t*>(signing_params); + if (ecdsa_params->digest_type != DIGEST_NONE) + return KM_ERROR_UNSUPPORTED_DIGEST; + if (!auth_set->push_back(TAG_DIGEST, KM_DIGEST_NONE)) + return KM_ERROR_MEMORY_ALLOCATION_FAILED; + } break; + default: + return KM_ERROR_UNSUPPORTED_ALGORITHM; + } + return KM_ERROR_OK; +} + +void TrustyKeymasterDevice::StoreNewKeyParams(AuthorizationSet* auth_set) { + auth_set->push_back(TAG_PURPOSE, KM_PURPOSE_SIGN); + auth_set->push_back(TAG_PURPOSE, KM_PURPOSE_VERIFY); + auth_set->push_back(TAG_ALL_USERS); + auth_set->push_back(TAG_NO_AUTH_REQUIRED); + uint64_t now = java_time(time(NULL)); + auth_set->push_back(TAG_CREATION_DATETIME, now); + auth_set->push_back(TAG_ORIGINATION_EXPIRE_DATETIME, now + HUNDRED_YEARS); + if (message_version_ == 0) { + auth_set->push_back(TAG_DIGEST_OLD, KM_DIGEST_NONE); + auth_set->push_back(TAG_PADDING_OLD, KM_PAD_NONE); + } else { + auth_set->push_back(TAG_DIGEST, KM_DIGEST_NONE); + auth_set->push_back(TAG_PADDING, KM_PAD_NONE); + } +} + +} // namespace keymaster |