| /* |
| * Copyright 2017 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 <keymasterV4_0/attestation_record.h> |
| |
| #include <android-base/logging.h> |
| #include <assert.h> |
| |
| #include <openssl/asn1t.h> |
| #include <openssl/bn.h> |
| #include <openssl/evp.h> |
| #include <openssl/x509.h> |
| |
| #include <keymasterV4_0/authorization_set.h> |
| #include <keymasterV4_0/openssl_utils.h> |
| |
| #define AT __FILE__ ":" << __LINE__ |
| |
| namespace android { |
| namespace hardware { |
| namespace keymaster { |
| namespace V4_0 { |
| |
| 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); |
| |
| 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* active_date_time; |
| ASN1_INTEGER* origination_expire_date_time; |
| ASN1_INTEGER* usage_expire_date_time; |
| ASN1_NULL* no_auth_required; |
| ASN1_INTEGER* user_auth_type; |
| ASN1_INTEGER* auth_timeout; |
| ASN1_NULL* allow_while_on_body; |
| ASN1_NULL* all_applications; |
| ASN1_OCTET_STRING* application_id; |
| ASN1_INTEGER* creation_date_time; |
| ASN1_INTEGER* origin; |
| ASN1_NULL* rollback_resistance; |
| KM_ROOT_OF_TRUST* root_of_trust; |
| ASN1_INTEGER* os_version; |
| ASN1_INTEGER* os_patchlevel; |
| ASN1_OCTET_STRING* attestation_application_id; |
| ASN1_NULL* trusted_user_presence_required; |
| ASN1_NULL* trusted_confirmation_required; |
| ASN1_NULL* unlocked_device_required; |
| ASN1_INTEGER* vendor_patchlevel; |
| ASN1_INTEGER* boot_patchlevel; |
| } 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_OPT(KM_AUTH_LIST, rollback_resistance, ASN1_NULL, TAG_ROLLBACK_RESISTANCE.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, 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, 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, attestation_application_id, ASN1_OCTET_STRING, |
| TAG_ATTESTATION_APPLICATION_ID.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* keymaster_version; |
| ASN1_ENUMERATED* keymaster_security_level; |
| ASN1_OCTET_STRING* attestation_challenge; |
| KM_AUTH_LIST* software_enforced; |
| KM_AUTH_LIST* tee_enforced; |
| ASN1_INTEGER* unique_id; |
| } 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, keymaster_version, ASN1_INTEGER), |
| ASN1_SIMPLE(KM_KEY_DESCRIPTION, keymaster_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 <Tag tag> |
| void copyAuthTag(const stack_st_ASN1_INTEGER* stack, TypedTag<TagType::ENUM_REP, tag> ttag, |
| AuthorizationSet* auth_list) { |
| typedef typename TypedTag2ValueType<decltype(ttag)>::type ValueT; |
| for (size_t i = 0; i < sk_ASN1_INTEGER_num(stack); ++i) { |
| auth_list->push_back( |
| ttag, static_cast<ValueT>(ASN1_INTEGER_get(sk_ASN1_INTEGER_value(stack, i)))); |
| } |
| } |
| |
| template <Tag tag> |
| void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag<TagType::ENUM, tag> ttag, |
| AuthorizationSet* auth_list) { |
| typedef typename TypedTag2ValueType<decltype(ttag)>::type ValueT; |
| if (!asn1_int) return; |
| auth_list->push_back(ttag, static_cast<ValueT>(ASN1_INTEGER_get(asn1_int))); |
| } |
| |
| template <Tag tag> |
| void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag<TagType::UINT, tag> 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<uint64_t>(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 <Tag tag> |
| void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag<TagType::ULONG, tag> 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 <Tag tag> |
| void copyAuthTag(const ASN1_INTEGER* asn1_int, TypedTag<TagType::DATE, tag> 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 <Tag tag> |
| void copyAuthTag(const ASN1_NULL* asn1_null, TypedTag<TagType::BOOL, tag> ttag, |
| AuthorizationSet* auth_list) { |
| if (!asn1_null) return; |
| auth_list->push_back(ttag); |
| } |
| |
| template <Tag tag> |
| void copyAuthTag(const ASN1_OCTET_STRING* asn1_string, TypedTag<TagType::BYTES, tag> ttag, |
| AuthorizationSet* auth_list) { |
| if (!asn1_string) return; |
| hidl_vec<uint8_t> buf; |
| buf.setToExternal(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. |
| static ErrorCode extract_auth_list(const KM_AUTH_LIST* record, AuthorizationSet* auth_list) { |
| if (!record) return ErrorCode::OK; |
| |
| copyAuthTag(record->active_date_time, TAG_ACTIVE_DATETIME, auth_list); |
| copyAuthTag(record->algorithm, TAG_ALGORITHM, auth_list); |
| copyAuthTag(record->application_id, TAG_APPLICATION_ID, auth_list); |
| copyAuthTag(record->auth_timeout, TAG_AUTH_TIMEOUT, auth_list); |
| copyAuthTag(record->creation_date_time, TAG_CREATION_DATETIME, auth_list); |
| copyAuthTag(record->digest, TAG_DIGEST, auth_list); |
| copyAuthTag(record->ec_curve, TAG_EC_CURVE, auth_list); |
| copyAuthTag(record->key_size, TAG_KEY_SIZE, auth_list); |
| copyAuthTag(record->no_auth_required, TAG_NO_AUTH_REQUIRED, auth_list); |
| copyAuthTag(record->origin, TAG_ORIGIN, auth_list); |
| copyAuthTag(record->origination_expire_date_time, TAG_ORIGINATION_EXPIRE_DATETIME, auth_list); |
| copyAuthTag(record->os_patchlevel, TAG_OS_PATCHLEVEL, auth_list); |
| copyAuthTag(record->os_version, TAG_OS_VERSION, auth_list); |
| copyAuthTag(record->padding, TAG_PADDING, auth_list); |
| copyAuthTag(record->purpose, TAG_PURPOSE, auth_list); |
| copyAuthTag(record->rollback_resistance, TAG_ROLLBACK_RESISTANCE, auth_list); |
| copyAuthTag(record->rsa_public_exponent, TAG_RSA_PUBLIC_EXPONENT, auth_list); |
| copyAuthTag(record->usage_expire_date_time, TAG_USAGE_EXPIRE_DATETIME, auth_list); |
| copyAuthTag(record->user_auth_type, TAG_USER_AUTH_TYPE, auth_list); |
| copyAuthTag(record->attestation_application_id, TAG_ATTESTATION_APPLICATION_ID, auth_list); |
| copyAuthTag(record->vendor_patchlevel, TAG_VENDOR_PATCHLEVEL, auth_list); |
| copyAuthTag(record->boot_patchlevel, TAG_BOOT_PATCHLEVEL, 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); |
| |
| return ErrorCode::OK; |
| } |
| |
| MAKE_OPENSSL_PTR_TYPE(KM_KEY_DESCRIPTION) |
| |
| // Parse the DER-encoded attestation record, placing the results in keymaster_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* keymaster_version, |
| SecurityLevel* keymaster_security_level, |
| hidl_vec<uint8_t>* attestation_challenge, |
| AuthorizationSet* software_enforced, |
| AuthorizationSet* tee_enforced, // |
| hidl_vec<uint8_t>* 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<SecurityLevel>(ASN1_ENUMERATED_get(record->attestation_security_level)); |
| *keymaster_version = ASN1_INTEGER_get(record->keymaster_version); |
| *keymaster_security_level = |
| static_cast<SecurityLevel>(ASN1_ENUMERATED_get(record->keymaster_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, |
| hidl_vec<uint8_t>* verified_boot_key, |
| keymaster_verified_boot_t* verified_boot_state, bool* device_locked, |
| hidl_vec<uint8_t>* 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; |
| } |
| if (!record->tee_enforced) { |
| LOG(ERROR) << AT << "Failed hardware characteristic parsing"; |
| return ErrorCode::INVALID_ARGUMENT; |
| } |
| if (!record->tee_enforced->root_of_trust) { |
| LOG(ERROR) << AT << "Failed root of trust parsing"; |
| return ErrorCode::INVALID_ARGUMENT; |
| } |
| if (!record->tee_enforced->root_of_trust->verified_boot_key) { |
| LOG(ERROR) << AT << "Failed verified boot key parsing"; |
| return ErrorCode::INVALID_ARGUMENT; |
| } |
| KM_ROOT_OF_TRUST* root_of_trust = record->tee_enforced->root_of_trust; |
| |
| 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<keymaster_verified_boot_t>( |
| 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 V4_0 |
| } // namespace keymaster |
| } // namespace hardware |
| } // namespace android |
