Release based on cl/313536507.

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I83ec7dee1a7ef6f4bdfd47482c94d03910525b7e

cpp/platform_v2/impl/g3/crypto.cc

@@ -0,0 +1,53 @@
+// Copyright 2020 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
+//
+//     https://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 "platform_v2/api/crypto.h"
+
+#include <cstdint>
+#include <string>
+
+#include "platform_v2/base/byte_array.h"
+#include "absl/strings/string_view.h"
+#include "openssl/digest.h"
+
+namespace location {
+namespace nearby {
+
+// Initialize global crypto state.
+void Crypto::Init() {}
+
+static ByteArray Hash(absl::string_view input, const EVP_MD* algo) {
+  unsigned int md_out_size = EVP_MAX_MD_SIZE;
+  uint8_t digest_buffer[EVP_MAX_MD_SIZE];
+  if (input.empty()) return {};
+
+  if (!EVP_Digest(input.data(), input.size(), digest_buffer, &md_out_size, algo,
+                  nullptr))
+    return {};
+
+  return ByteArray{reinterpret_cast<char*>(digest_buffer), md_out_size};
+}
+
+// Return MD5 hash of input.
+ByteArray Crypto::Md5(absl::string_view input) {
+  return Hash(input, EVP_md5());
+}
+
+// Return SHA256 hash of input.
+ByteArray Crypto::Sha256(absl::string_view input) {
+  return Hash(input, EVP_sha256());
+}
+
+}  // namespace nearby
+}  // namespace location