/* * Copyright 2020 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 #include #include #include #include #include #include #include #include #include #include #define AT __FILE__ ":" << __LINE__ namespace aidl::android::hardware::security::keymint { struct stack_st_ASN1_TYPE_Delete { void operator()(stack_st_ASN1_TYPE* p) { sk_ASN1_TYPE_free(p); } }; struct ASN1_STRING_Delete { void operator()(ASN1_STRING* p) { ASN1_STRING_free(p); } }; struct ASN1_TYPE_Delete { void operator()(ASN1_TYPE* p) { ASN1_TYPE_free(p); } }; #define ASN1_INTEGER_SET STACK_OF(ASN1_INTEGER) typedef struct km_root_of_trust { ASN1_OCTET_STRING* verified_boot_key; ASN1_BOOLEAN device_locked; ASN1_ENUMERATED* verified_boot_state; ASN1_OCTET_STRING* verified_boot_hash; } KM_ROOT_OF_TRUST; ASN1_SEQUENCE(KM_ROOT_OF_TRUST) = { ASN1_SIMPLE(KM_ROOT_OF_TRUST, verified_boot_key, ASN1_OCTET_STRING), ASN1_SIMPLE(KM_ROOT_OF_TRUST, device_locked, ASN1_BOOLEAN), ASN1_SIMPLE(KM_ROOT_OF_TRUST, verified_boot_state, ASN1_ENUMERATED), ASN1_SIMPLE(KM_ROOT_OF_TRUST, verified_boot_hash, ASN1_OCTET_STRING), } ASN1_SEQUENCE_END(KM_ROOT_OF_TRUST); IMPLEMENT_ASN1_FUNCTIONS(KM_ROOT_OF_TRUST); // Fields ordered in tag order. typedef struct km_auth_list { ASN1_INTEGER_SET* purpose; ASN1_INTEGER* algorithm; ASN1_INTEGER* key_size; ASN1_INTEGER_SET* digest; ASN1_INTEGER_SET* padding; ASN1_INTEGER* ec_curve; ASN1_INTEGER* rsa_public_exponent; ASN1_INTEGER_SET* mgf_digest; ASN1_NULL* rollback_resistance; ASN1_NULL* early_boot_only; ASN1_INTEGER* active_date_time; ASN1_INTEGER* origination_expire_date_time; ASN1_INTEGER* usage_expire_date_time; ASN1_INTEGER* usage_count_limit; ASN1_NULL* no_auth_required; ASN1_INTEGER* user_auth_type; ASN1_INTEGER* auth_timeout; ASN1_NULL* allow_while_on_body; ASN1_NULL* trusted_user_presence_required; ASN1_NULL* trusted_confirmation_required; ASN1_NULL* unlocked_device_required; ASN1_INTEGER* creation_date_time; ASN1_INTEGER* origin; KM_ROOT_OF_TRUST* root_of_trust; ASN1_INTEGER* os_version; ASN1_INTEGER* os_patchlevel; ASN1_OCTET_STRING* attestation_application_id; ASN1_OCTET_STRING* attestation_id_brand; ASN1_OCTET_STRING* attestation_id_device; ASN1_OCTET_STRING* attestation_id_product; ASN1_OCTET_STRING* attestation_id_serial; ASN1_OCTET_STRING* attestation_id_imei; ASN1_OCTET_STRING* attestation_id_meid; ASN1_OCTET_STRING* attestation_id_manufacturer; ASN1_OCTET_STRING* attestation_id_model; ASN1_INTEGER* vendor_patchlevel; ASN1_INTEGER* boot_patchlevel; ASN1_NULL* device_unique_attestation; ASN1_NULL* identity_credential; ASN1_OCTET_STRING* attestation_id_second_imei; ASN1_OCTET_STRING* module_hash; } KM_AUTH_LIST; ASN1_SEQUENCE(KM_AUTH_LIST) = { ASN1_EXP_SET_OF_OPT(KM_AUTH_LIST, purpose, ASN1_INTEGER, TAG_PURPOSE.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, algorithm, ASN1_INTEGER, TAG_ALGORITHM.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, key_size, ASN1_INTEGER, TAG_KEY_SIZE.maskedTag()), ASN1_EXP_SET_OF_OPT(KM_AUTH_LIST, digest, ASN1_INTEGER, TAG_DIGEST.maskedTag()), ASN1_EXP_SET_OF_OPT(KM_AUTH_LIST, padding, ASN1_INTEGER, TAG_PADDING.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, ec_curve, ASN1_INTEGER, TAG_EC_CURVE.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, rsa_public_exponent, ASN1_INTEGER, TAG_RSA_PUBLIC_EXPONENT.maskedTag()), ASN1_EXP_SET_OF_OPT(KM_AUTH_LIST, mgf_digest, ASN1_INTEGER, TAG_RSA_OAEP_MGF_DIGEST.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, rollback_resistance, ASN1_NULL, TAG_ROLLBACK_RESISTANCE.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, early_boot_only, ASN1_NULL, TAG_EARLY_BOOT_ONLY.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, active_date_time, ASN1_INTEGER, TAG_ACTIVE_DATETIME.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, origination_expire_date_time, ASN1_INTEGER, TAG_ORIGINATION_EXPIRE_DATETIME.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, usage_expire_date_time, ASN1_INTEGER, TAG_USAGE_EXPIRE_DATETIME.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, usage_count_limit, ASN1_INTEGER, TAG_USAGE_COUNT_LIMIT.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, no_auth_required, ASN1_NULL, TAG_NO_AUTH_REQUIRED.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, user_auth_type, ASN1_INTEGER, TAG_USER_AUTH_TYPE.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, auth_timeout, ASN1_INTEGER, TAG_AUTH_TIMEOUT.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, allow_while_on_body, ASN1_NULL, TAG_ALLOW_WHILE_ON_BODY.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, trusted_user_presence_required, ASN1_NULL, TAG_TRUSTED_USER_PRESENCE_REQUIRED.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, trusted_confirmation_required, ASN1_NULL, TAG_TRUSTED_CONFIRMATION_REQUIRED.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, unlocked_device_required, ASN1_NULL, TAG_UNLOCKED_DEVICE_REQUIRED.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, creation_date_time, ASN1_INTEGER, TAG_CREATION_DATETIME.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, origin, ASN1_INTEGER, TAG_ORIGIN.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, root_of_trust, KM_ROOT_OF_TRUST, TAG_ROOT_OF_TRUST.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, os_version, ASN1_INTEGER, TAG_OS_VERSION.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, os_patchlevel, ASN1_INTEGER, TAG_OS_PATCHLEVEL.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_application_id, ASN1_OCTET_STRING, TAG_ATTESTATION_APPLICATION_ID.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_brand, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_BRAND.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_device, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_DEVICE.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_product, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_PRODUCT.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_serial, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_SERIAL.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_imei, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_IMEI.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_meid, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_MEID.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_manufacturer, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_MANUFACTURER.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_model, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_MODEL.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, vendor_patchlevel, ASN1_INTEGER, TAG_VENDOR_PATCHLEVEL.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, boot_patchlevel, ASN1_INTEGER, TAG_BOOT_PATCHLEVEL.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, device_unique_attestation, ASN1_NULL, TAG_DEVICE_UNIQUE_ATTESTATION.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, identity_credential, ASN1_NULL, TAG_IDENTITY_CREDENTIAL_KEY.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, attestation_id_second_imei, ASN1_OCTET_STRING, TAG_ATTESTATION_ID_SECOND_IMEI.maskedTag()), ASN1_EXP_OPT(KM_AUTH_LIST, module_hash, ASN1_OCTET_STRING, TAG_MODULE_HASH.maskedTag()), } ASN1_SEQUENCE_END(KM_AUTH_LIST); IMPLEMENT_ASN1_FUNCTIONS(KM_AUTH_LIST); typedef struct km_key_description { ASN1_INTEGER* attestation_version; ASN1_ENUMERATED* attestation_security_level; ASN1_INTEGER* keymint_version; ASN1_ENUMERATED* keymint_security_level; ASN1_OCTET_STRING* attestation_challenge; ASN1_INTEGER* unique_id; KM_AUTH_LIST* software_enforced; KM_AUTH_LIST* tee_enforced; } KM_KEY_DESCRIPTION; ASN1_SEQUENCE(KM_KEY_DESCRIPTION) = { ASN1_SIMPLE(KM_KEY_DESCRIPTION, attestation_version, ASN1_INTEGER), ASN1_SIMPLE(KM_KEY_DESCRIPTION, attestation_security_level, ASN1_ENUMERATED), ASN1_SIMPLE(KM_KEY_DESCRIPTION, keymint_version, ASN1_INTEGER), ASN1_SIMPLE(KM_KEY_DESCRIPTION, keymint_security_level, ASN1_ENUMERATED), ASN1_SIMPLE(KM_KEY_DESCRIPTION, attestation_challenge, ASN1_OCTET_STRING), ASN1_SIMPLE(KM_KEY_DESCRIPTION, unique_id, ASN1_OCTET_STRING), ASN1_SIMPLE(KM_KEY_DESCRIPTION, software_enforced, KM_AUTH_LIST), ASN1_SIMPLE(KM_KEY_DESCRIPTION, tee_enforced, KM_AUTH_LIST), } ASN1_SEQUENCE_END(KM_KEY_DESCRIPTION); IMPLEMENT_ASN1_FUNCTIONS(KM_KEY_DESCRIPTION); template void copyAuthTag(const stack_st_ASN1_INTEGER* stack, TypedTag ttag, AuthorizationSet* auth_list) { typedef typename TypedTag2ValueType::type ValueT; for (size_t i = 0; i < sk_ASN1_INTEGER_num(stack); ++i) { auth_list->push_back( ttag, static_cast(ASN1_INTEGER_get(sk_ASN1_INTEGER_value(stack, i)))); } } template void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag ttag, AuthorizationSet* auth_list) { typedef typename TypedTag2ValueType::type ValueT; if (!asn1_int) return; auth_list->push_back(ttag, static_cast(ASN1_INTEGER_get(asn1_int))); } template void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag ttag, AuthorizationSet* auth_list) { if (!asn1_int) return; auth_list->push_back(ttag, ASN1_INTEGER_get(asn1_int)); } BIGNUM* construct_uint_max() { BIGNUM* value = BN_new(); BIGNUM_Ptr one(BN_new()); BN_one(one.get()); BN_lshift(value, one.get(), 32); return value; } uint64_t BignumToUint64(BIGNUM* num) { static_assert((sizeof(BN_ULONG) == sizeof(uint32_t)) || (sizeof(BN_ULONG) == sizeof(uint64_t)), "This implementation only supports 32 and 64-bit BN_ULONG"); if (sizeof(BN_ULONG) == sizeof(uint32_t)) { BIGNUM_Ptr uint_max(construct_uint_max()); BIGNUM_Ptr hi(BN_new()), lo(BN_new()); BN_CTX_Ptr ctx(BN_CTX_new()); BN_div(hi.get(), lo.get(), num, uint_max.get(), ctx.get()); return static_cast(BN_get_word(hi.get())) << 32 | BN_get_word(lo.get()); } else if (sizeof(BN_ULONG) == sizeof(uint64_t)) { return BN_get_word(num); } else { return 0; } } template void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag ttag, AuthorizationSet* auth_list) { if (!asn1_int) return; BIGNUM_Ptr num(ASN1_INTEGER_to_BN(asn1_int, nullptr)); auth_list->push_back(ttag, BignumToUint64(num.get())); } template void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag ttag, AuthorizationSet* auth_list) { if (!asn1_int) return; BIGNUM_Ptr num(ASN1_INTEGER_to_BN(asn1_int, nullptr)); auth_list->push_back(ttag, BignumToUint64(num.get())); } template void copyAuthTag(const ASN1_NULL* asn1_null, TypedTag ttag, AuthorizationSet* auth_list) { if (!asn1_null) return; auth_list->push_back(ttag); } template void copyAuthTag(const ASN1_OCTET_STRING* asn1_string, TypedTag ttag, AuthorizationSet* auth_list) { if (!asn1_string) return; vector buf(asn1_string->data, asn1_string->data + asn1_string->length); auth_list->push_back(ttag, buf); } // Extract the values from the specified ASN.1 record and place them in auth_list. // Does nothing with root-of-trust field. static ErrorCode extract_auth_list(const KM_AUTH_LIST* record, AuthorizationSet* auth_list) { if (!record) return ErrorCode::OK; // Fields ordered in tag order. copyAuthTag(record->purpose, TAG_PURPOSE, auth_list); copyAuthTag(record->algorithm, TAG_ALGORITHM, auth_list); copyAuthTag(record->key_size, TAG_KEY_SIZE, auth_list); copyAuthTag(record->digest, TAG_DIGEST, auth_list); copyAuthTag(record->padding, TAG_PADDING, auth_list); copyAuthTag(record->ec_curve, TAG_EC_CURVE, auth_list); copyAuthTag(record->rsa_public_exponent, TAG_RSA_PUBLIC_EXPONENT, auth_list); copyAuthTag(record->mgf_digest, TAG_RSA_OAEP_MGF_DIGEST, auth_list); copyAuthTag(record->rollback_resistance, TAG_ROLLBACK_RESISTANCE, auth_list); copyAuthTag(record->early_boot_only, TAG_EARLY_BOOT_ONLY, auth_list); copyAuthTag(record->active_date_time, TAG_ACTIVE_DATETIME, auth_list); copyAuthTag(record->origination_expire_date_time, TAG_ORIGINATION_EXPIRE_DATETIME, auth_list); copyAuthTag(record->usage_expire_date_time, TAG_USAGE_EXPIRE_DATETIME, auth_list); copyAuthTag(record->usage_count_limit, TAG_USAGE_COUNT_LIMIT, auth_list); copyAuthTag(record->no_auth_required, TAG_NO_AUTH_REQUIRED, auth_list); copyAuthTag(record->user_auth_type, TAG_USER_AUTH_TYPE, auth_list); copyAuthTag(record->auth_timeout, TAG_AUTH_TIMEOUT, auth_list); copyAuthTag(record->allow_while_on_body, TAG_ALLOW_WHILE_ON_BODY, auth_list); copyAuthTag(record->trusted_user_presence_required, TAG_TRUSTED_USER_PRESENCE_REQUIRED, auth_list); copyAuthTag(record->trusted_confirmation_required, TAG_TRUSTED_CONFIRMATION_REQUIRED, auth_list); copyAuthTag(record->unlocked_device_required, TAG_UNLOCKED_DEVICE_REQUIRED, auth_list); copyAuthTag(record->creation_date_time, TAG_CREATION_DATETIME, auth_list); copyAuthTag(record->origin, TAG_ORIGIN, auth_list); // root_of_trust dealt with separately copyAuthTag(record->os_version, TAG_OS_VERSION, auth_list); copyAuthTag(record->os_patchlevel, TAG_OS_PATCHLEVEL, auth_list); copyAuthTag(record->attestation_application_id, TAG_ATTESTATION_APPLICATION_ID, auth_list); copyAuthTag(record->attestation_id_brand, TAG_ATTESTATION_ID_BRAND, auth_list); copyAuthTag(record->attestation_id_device, TAG_ATTESTATION_ID_DEVICE, auth_list); copyAuthTag(record->attestation_id_product, TAG_ATTESTATION_ID_PRODUCT, auth_list); copyAuthTag(record->attestation_id_serial, TAG_ATTESTATION_ID_SERIAL, auth_list); copyAuthTag(record->attestation_id_imei, TAG_ATTESTATION_ID_IMEI, auth_list); copyAuthTag(record->attestation_id_meid, TAG_ATTESTATION_ID_MEID, auth_list); copyAuthTag(record->attestation_id_manufacturer, TAG_ATTESTATION_ID_MANUFACTURER, auth_list); copyAuthTag(record->attestation_id_model, TAG_ATTESTATION_ID_MODEL, auth_list); copyAuthTag(record->vendor_patchlevel, TAG_VENDOR_PATCHLEVEL, auth_list); copyAuthTag(record->boot_patchlevel, TAG_BOOT_PATCHLEVEL, auth_list); copyAuthTag(record->device_unique_attestation, TAG_DEVICE_UNIQUE_ATTESTATION, auth_list); copyAuthTag(record->identity_credential, TAG_IDENTITY_CREDENTIAL_KEY, auth_list); copyAuthTag(record->attestation_id_second_imei, TAG_ATTESTATION_ID_SECOND_IMEI, auth_list); copyAuthTag(record->module_hash, TAG_MODULE_HASH, auth_list); return ErrorCode::OK; } MAKE_OPENSSL_PTR_TYPE(KM_KEY_DESCRIPTION) // Parse the DER-encoded attestation record, placing the results in keymint_version, // attestation_challenge, software_enforced, tee_enforced and unique_id. ErrorCode parse_attestation_record(const uint8_t* asn1_key_desc, size_t asn1_key_desc_len, uint32_t* attestation_version, // SecurityLevel* attestation_security_level, uint32_t* keymint_version, SecurityLevel* keymint_security_level, vector* attestation_challenge, AuthorizationSet* software_enforced, AuthorizationSet* tee_enforced, // vector* unique_id) { const uint8_t* p = asn1_key_desc; KM_KEY_DESCRIPTION_Ptr record(d2i_KM_KEY_DESCRIPTION(nullptr, &p, asn1_key_desc_len)); if (!record.get()) return ErrorCode::UNKNOWN_ERROR; *attestation_version = ASN1_INTEGER_get(record->attestation_version); *attestation_security_level = static_cast(ASN1_ENUMERATED_get(record->attestation_security_level)); *keymint_version = ASN1_INTEGER_get(record->keymint_version); *keymint_security_level = static_cast(ASN1_ENUMERATED_get(record->keymint_security_level)); auto& chall = record->attestation_challenge; attestation_challenge->resize(chall->length); memcpy(attestation_challenge->data(), chall->data, chall->length); auto& uid = record->unique_id; unique_id->resize(uid->length); memcpy(unique_id->data(), uid->data, uid->length); ErrorCode error = extract_auth_list(record->software_enforced, software_enforced); if (error != ErrorCode::OK) return error; return extract_auth_list(record->tee_enforced, tee_enforced); } ErrorCode parse_root_of_trust(const uint8_t* asn1_key_desc, size_t asn1_key_desc_len, vector* verified_boot_key, VerifiedBoot* verified_boot_state, bool* device_locked, vector* verified_boot_hash) { if (!verified_boot_key || !verified_boot_state || !device_locked || !verified_boot_hash) { LOG(ERROR) << AT << "null pointer input(s)"; return ErrorCode::INVALID_ARGUMENT; } const uint8_t* p = asn1_key_desc; KM_KEY_DESCRIPTION_Ptr record(d2i_KM_KEY_DESCRIPTION(nullptr, &p, asn1_key_desc_len)); if (!record.get()) { LOG(ERROR) << AT << "Failed record parsing"; return ErrorCode::UNKNOWN_ERROR; } KM_ROOT_OF_TRUST* root_of_trust = nullptr; if (record->tee_enforced && record->tee_enforced->root_of_trust) { root_of_trust = record->tee_enforced->root_of_trust; } else if (record->software_enforced && record->software_enforced->root_of_trust) { root_of_trust = record->software_enforced->root_of_trust; } else { LOG(ERROR) << AT << " Failed root of trust parsing"; return ErrorCode::INVALID_ARGUMENT; } if (!root_of_trust->verified_boot_key) { LOG(ERROR) << AT << " Failed verified boot key parsing"; return ErrorCode::INVALID_ARGUMENT; } auto& vb_key = root_of_trust->verified_boot_key; verified_boot_key->resize(vb_key->length); memcpy(verified_boot_key->data(), vb_key->data, vb_key->length); *verified_boot_state = static_cast(ASN1_ENUMERATED_get(root_of_trust->verified_boot_state)); if (!verified_boot_state) { LOG(ERROR) << AT << " Failed verified boot state parsing"; return ErrorCode::INVALID_ARGUMENT; } *device_locked = root_of_trust->device_locked; if (!device_locked) { LOG(ERROR) << AT << " Failed device locked parsing"; return ErrorCode::INVALID_ARGUMENT; } auto& vb_hash = root_of_trust->verified_boot_hash; if (!vb_hash) { LOG(ERROR) << AT << " Failed verified boot hash parsing"; return ErrorCode::INVALID_ARGUMENT; } verified_boot_hash->resize(vb_hash->length); memcpy(verified_boot_hash->data(), vb_hash->data, vb_hash->length); return ErrorCode::OK; // KM_ERROR_OK; } } // namespace aidl::android::hardware::security::keymint