Internal change.

PiperOrigin-RevId: 693123259
Change-Id: I3d9d97f1d887272878ebab0a6035d0aa49912ef5

proto/slh_dsa.proto

@@ -0,0 +1,67 @@
+// Copyright 2024 Google LLC
+//
+// 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.
+//
+///////////////////////////////////////////////////////////////////////////////
+syntax = "proto3";
+
+package google.crypto.tink;
+
+enum SlhDsaHashType {
+  SLH_DSA_HASH_TYPE_UNSPECIFIED = 0;
+  SHA2 = 1;
+  SHAKE = 2;
+}
+
+enum SlhDsaSignatureType {
+  SLH_DSA_SIGNATURE_TYPE_UNSPECIFIED = 0;
+  FAST_SIGNING = 1;
+  SMALL_SIGNATURE = 2;
+}
+
+// Protos for the Stateless Hash-Based Digital Signature Algorithm
+// https://csrc.nist.gov/pubs/fips/205/final
+message SlhDsaParams {
+  // Required
+  int32 key_size = 1;
+  // Required.
+  SlhDsaHashType hash_type = 2;
+  // Required.
+  SlhDsaSignatureType sig_type = 3;
+}
+
+message SlhDsaKeyFormat {
+  uint32 version = 1;
+  // Required.
+  SlhDsaParams params = 2;
+}
+
+// key_type: type.googleapis.com/google.crypto.tink.SlhDsaPublicKey
+message SlhDsaPublicKey {
+  // Required.
+  uint32 version = 1;
+  // Required.
+  bytes key_value = 2;  // Placeholder for ctype.
+  // Required
+  SlhDsaParams params = 3;
+}
+
+// key_type: type.googleapis.com/google.crypto.tink.SlhDsaPrivateKey
+message SlhDsaPrivateKey {
+  // Required.
+  uint32 version = 1;
+  // Required.
+  bytes key_value = 2;  // Placeholder for ctype.
+  // Required. The corresponding public key.
+  SlhDsaPublicKey public_key = 3;
+}