| // Copyright 2018 Google Inc. |
| // |
| // 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 "tink/signature/rsa_ssa_pss_sign_key_manager.h" |
| |
| #include "absl/memory/memory.h" |
| #include "absl/strings/string_view.h" |
| #include "tink/key_manager.h" |
| #include "tink/public_key_sign.h" |
| #include "tink/signature/rsa_ssa_pss_verify_key_manager.h" |
| #include "tink/signature/sig_util.h" |
| #include "tink/subtle/rsa_ssa_pss_sign_boringssl.h" |
| #include "tink/subtle/subtle_util_boringssl.h" |
| #include "tink/util/enums.h" |
| #include "tink/util/errors.h" |
| #include "tink/util/protobuf_helper.h" |
| #include "tink/util/status.h" |
| #include "tink/util/statusor.h" |
| #include "tink/util/validation.h" |
| #include "proto/rsa_ssa_pss.pb.h" |
| #include "proto/tink.pb.h" |
| |
| namespace crypto { |
| namespace tink { |
| |
| using crypto::tink::util::Enums; |
| using crypto::tink::util::Status; |
| using crypto::tink::util::StatusOr; |
| using google::crypto::tink::KeyData; |
| using google::crypto::tink::RsaSsaPssKeyFormat; |
| using google::crypto::tink::RsaSsaPssParams; |
| using google::crypto::tink::RsaSsaPssPrivateKey; |
| |
| namespace { |
| std::unique_ptr<RsaSsaPssPrivateKey> RsaPrivateKeySubtleToProto( |
| const subtle::SubtleUtilBoringSSL::RsaPrivateKey& private_key) { |
| auto key_proto = absl::make_unique<RsaSsaPssPrivateKey>(); |
| key_proto->set_version(RsaSsaPssSignKeyManager::kVersion); |
| key_proto->set_d(private_key.d); |
| key_proto->set_p(private_key.p); |
| key_proto->set_q(private_key.q); |
| key_proto->set_dp(private_key.dp); |
| key_proto->set_dq(private_key.dq); |
| key_proto->set_crt(private_key.crt); |
| auto* public_key_proto = key_proto->mutable_public_key(); |
| public_key_proto->set_version(RsaSsaPssSignKeyManager::kVersion); |
| public_key_proto->set_n(private_key.n); |
| public_key_proto->set_e(private_key.e); |
| return key_proto; |
| } |
| |
| subtle::SubtleUtilBoringSSL::RsaPrivateKey RsaPrivateKeyProtoToSubtle( |
| const RsaSsaPssPrivateKey& key_proto) { |
| subtle::SubtleUtilBoringSSL::RsaPrivateKey key; |
| key.n = key_proto.public_key().n(); |
| key.e = key_proto.public_key().e(); |
| key.d = key_proto.d(); |
| key.p = key_proto.p(); |
| key.q = key_proto.q(); |
| key.dp = key_proto.dp(); |
| key.dq = key_proto.dq(); |
| key.crt = key_proto.crt(); |
| return key; |
| } |
| |
| } // namespace |
| |
| class RsaSsaPssPrivateKeyFactory |
| : public PrivateKeyFactory, |
| public KeyFactoryBase<RsaSsaPssPrivateKey, RsaSsaPssKeyFormat> { |
| public: |
| RsaSsaPssPrivateKeyFactory() {} |
| |
| KeyData::KeyMaterialType key_material_type() const override { |
| return KeyData::ASYMMETRIC_PRIVATE; |
| } |
| |
| // Returns KeyData proto that contains RsaSsaPssPublicKey |
| // extracted from the given serialized_private_key, which must contain |
| // RsaSsaPssPrivateKey-proto. |
| crypto::tink::util::StatusOr<std::unique_ptr<google::crypto::tink::KeyData>> |
| GetPublicKeyData(absl::string_view serialized_private_key) const override; |
| |
| protected: |
| StatusOr<std::unique_ptr<RsaSsaPssPrivateKey>> NewKeyFromFormat( |
| const RsaSsaPssKeyFormat& rsa_ssa_pss_key_format) const override; |
| }; |
| |
| StatusOr<std::unique_ptr<RsaSsaPssPrivateKey>> |
| RsaSsaPssPrivateKeyFactory::NewKeyFromFormat( |
| const RsaSsaPssKeyFormat& rsa_ssa_pss_key_format) const { |
| util::Status is_valid = |
| RsaSsaPssSignKeyManager::Validate(rsa_ssa_pss_key_format); |
| if (!is_valid.ok()) return is_valid; |
| |
| auto e = subtle::SubtleUtilBoringSSL::str2bn( |
| rsa_ssa_pss_key_format.public_exponent()); |
| if (!e.ok()) return e.status(); |
| |
| subtle::SubtleUtilBoringSSL::RsaPrivateKey private_key; |
| subtle::SubtleUtilBoringSSL::RsaPublicKey public_key; |
| util::Status status = subtle::SubtleUtilBoringSSL::GetNewRsaKeyPair( |
| rsa_ssa_pss_key_format.modulus_size_in_bits(), e.ValueOrDie().get(), |
| &private_key, &public_key); |
| if (!status.ok()) return status; |
| |
| auto key_proto = RsaPrivateKeySubtleToProto(private_key); |
| auto* public_key_proto = key_proto->mutable_public_key(); |
| *public_key_proto->mutable_params() = rsa_ssa_pss_key_format.params(); |
| return absl::implicit_cast<StatusOr<std::unique_ptr<RsaSsaPssPrivateKey>>>( |
| std::move(key_proto)); |
| } |
| |
| StatusOr<std::unique_ptr<KeyData>> RsaSsaPssPrivateKeyFactory::GetPublicKeyData( |
| absl::string_view serialized_private_key) const { |
| RsaSsaPssPrivateKey private_key; |
| if (!private_key.ParseFromString(std::string(serialized_private_key))) { |
| return ToStatusF(util::error::INVALID_ARGUMENT, |
| "Could not parse the passed string as proto '%s'.", |
| RsaSsaPssVerifyKeyManager::static_key_type().c_str()); |
| } |
| auto status = RsaSsaPssSignKeyManager::Validate(private_key); |
| if (!status.ok()) return status; |
| auto key_data = absl::make_unique<KeyData>(); |
| key_data->set_type_url(RsaSsaPssVerifyKeyManager::static_key_type()); |
| key_data->set_value(private_key.public_key().SerializeAsString()); |
| key_data->set_key_material_type(KeyData::ASYMMETRIC_PUBLIC); |
| return std::move(key_data); |
| } |
| |
| constexpr uint32_t RsaSsaPssSignKeyManager::kVersion; |
| |
| RsaSsaPssSignKeyManager::RsaSsaPssSignKeyManager() |
| : key_factory_(absl::make_unique<RsaSsaPssPrivateKeyFactory>()) {} |
| |
| const KeyFactory& RsaSsaPssSignKeyManager::get_key_factory() const { |
| return *key_factory_; |
| } |
| |
| uint32_t RsaSsaPssSignKeyManager::get_version() const { return kVersion; } |
| |
| StatusOr<std::unique_ptr<PublicKeySign>> |
| RsaSsaPssSignKeyManager::GetPrimitiveFromKey( |
| const RsaSsaPssPrivateKey& key_proto) const { |
| Status status = Validate(key_proto); |
| if (!status.ok()) return status; |
| auto key = RsaPrivateKeyProtoToSubtle(key_proto); |
| subtle::SubtleUtilBoringSSL::RsaSsaPssParams params; |
| const RsaSsaPssParams& params_proto = key_proto.public_key().params(); |
| params.sig_hash = Enums::ProtoToSubtle(params_proto.sig_hash()); |
| params.mgf1_hash = Enums::ProtoToSubtle(params_proto.mgf1_hash()); |
| params.salt_length = params_proto.salt_length(); |
| auto signer = subtle::RsaSsaPssSignBoringSsl::New(key, params); |
| if (!signer.ok()) return signer.status(); |
| // To check that the key is correct, we sign a test message with private key |
| // and verify with public key. |
| auto public_key_data_result = |
| key_factory_->GetPublicKeyData(key_proto.SerializeAsString()); |
| auto public_key_data = std::move(public_key_data_result.ValueOrDie()); |
| RsaSsaPssVerifyKeyManager verify_key_manager; |
| auto verifier = verify_key_manager.GetPrimitive(*public_key_data); |
| if (!verifier.ok()) return verifier.status(); |
| auto sign_verify_result = |
| SignAndVerify(signer.ValueOrDie().get(), verifier.ValueOrDie().get()); |
| if (!sign_verify_result.ok()) { |
| return util::Status(util::error::INTERNAL, |
| "security bug: signing with private key followed by " |
| "verifying with public key failed"); |
| } |
| return signer; |
| } |
| |
| // static |
| Status RsaSsaPssSignKeyManager::Validate(const RsaSsaPssPrivateKey& key) { |
| Status status = ValidateVersion(key.version(), kVersion); |
| if (!status.ok()) return status; |
| return RsaSsaPssVerifyKeyManager::Validate(key.public_key()); |
| } |
| |
| // static |
| Status RsaSsaPssSignKeyManager::Validate(const RsaSsaPssKeyFormat& key_format) { |
| auto modulus_status = subtle::SubtleUtilBoringSSL::ValidateRsaModulusSize( |
| key_format.modulus_size_in_bits()); |
| if (!modulus_status.ok()) return modulus_status; |
| return RsaSsaPssVerifyKeyManager::Validate(key_format.params()); |
| } |
| } // namespace tink |
| } // namespace crypto |