[ate,cp] add reference CP test program boilerplate

This adds reference CP test program boilerplate code. This partially
addresses lowRISC#6.

Signed-off-by: Tim Trippel <[email protected]>

src/ate/test_programs/BUILD.bazel

@@ -0,0 +1,19 @@
+# Copyright lowRISC contributors (OpenTitan project).
+# Licensed under the Apache License, Version 2.0, see LICENSE for details.
+# SPDX-License-Identifier: Apache-2.0
+
+package(default_visibility = ["//visibility:public"])
+
+cc_binary(
+    name = "cp",
+    srcs = ["cp.cc"],
+    deps = [
+        "//src/ate:ate_client",
+        "//src/version",
+        "@com_google_absl//absl/flags:flag",
+        "@com_google_absl//absl/flags:parse",
+        "@com_google_absl//absl/log",
+        "@com_google_absl//absl/status",
+        "@com_google_absl//absl/status:statusor",
+    ],
+)

src/ate/test_programs/cp.cc

@@ -0,0 +1,117 @@
+// Copyright lowRISC contributors (OpenTitan project).
+// Licensed under the Apache License, Version 2.0, see LICENSE for details.
+// SPDX-License-Identifier: Apache-2.0
+
+#include <grpcpp/grpcpp.h>
+
+#include <fstream>
+#include <iostream>
+#include <memory>
+#include <string>
+#include <unordered_map>
+
+#include "absl/flags/flag.h"
+#include "absl/flags/parse.h"
+#include "absl/flags/usage_config.h"
+#include "absl/log/log.h"
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "src/ate/ate_client.h"
+#include "src/pa/proto/pa.grpc.pb.h"
+#include "src/version/version.h"
+
+/**
+ * PA configuration flags.
+ */
+ABSL_FLAG(std::string, pa_socket, "", "host:port of the PA server.");
+ABSL_FLAG(std::string, sku, "", "SKU string to initialize the PA session.");
+ABSL_FLAG(std::string, sku_auth_pw, "",
+          "SKU authorization password string to initialize the PA session.");
+
+/**
+ * mTLS configuration flags.
+ */
+ABSL_FLAG(bool, enable_mtls, false, "Enable mTLS secure channel.");
+ABSL_FLAG(std::string, client_key, "",
+          "File path to the PEM encoding of the client's private key.");
+ABSL_FLAG(std::string, client_cert, "",
+          "File path to the PEM encoding of the  client's certificate chain.");
+ABSL_FLAG(std::string, ca_root_certs, "",
+          "File path to the PEM encoding of the server root certificates.");
+
+namespace {
+using provisioning::VersionFormatted;
+using provisioning::ate::AteClient;
+
+// Returns `filename` content in a std::string format
+absl::StatusOr<std::string> ReadFile(const std::string &filename) {
+  auto output_stream = std::ostringstream();
+  std::ifstream file_stream(filename);
+  if (!file_stream.is_open()) {
+    return absl::InvalidArgumentError(
+        absl::StrCat("Unable to open file: \"", filename, "\""));
+  }
+  output_stream << file_stream.rdbuf();
+  return output_stream.str();
+}
+
+}  // namespace
+
+int main(int argc, char **argv) {
+  // Parse cmd line args.
+  absl::FlagsUsageConfig config;
+  config.version_string = &VersionFormatted;
+  absl::SetFlagsUsageConfig(config);
+  absl::ParseCommandLine(argc, argv);
+  LOG(INFO) << VersionFormatted();
+
+  // Extract and validate ATE client options.
+  AteClient::Options options;
+  options.pa_socket = absl::GetFlag(FLAGS_pa_socket);
+  options.enable_mtls = absl::GetFlag(FLAGS_enable_mtls);
+  if (options.enable_mtls) {
+    std::unordered_map<absl::Flag<std::string> *, std::string *> pem_options = {
+        {&FLAGS_client_key, &options.pem_private_key},
+        {&FLAGS_client_cert, &options.pem_cert_chain},
+        {&FLAGS_ca_root_certs, &options.pem_root_certs},
+    };
+
+    for (auto opt : pem_options) {
+      std::string filename = absl::GetFlag(*opt.first);
+      if (filename.empty()) {
+        LOG(ERROR) << "--" << absl::GetFlagReflectionHandle(*opt.first).Name()
+                   << " not set. This is a required argument when "
+                   << " --enable_mtls is set to true." << std::endl;
+        return -1;
+      }
+      auto result = ReadFile(filename);
+      if (!result.ok()) {
+        LOG(ERROR) << "--" << absl::GetFlagReflectionHandle(*opt.first).Name()
+                   << " " << result.status() << std::endl;
+        return -1;
+      }
+      *opt.second = result.value();
+    }
+  }
+
+  // Instantiate a client.
+  auto ate = AteClient::Create(options);
+
+  // Init/Close session.
+  grpc::Status status = ate->InitSession(absl::GetFlag(FLAGS_sku),
+                                         absl::GetFlag(FLAGS_sku_auth_pw));
+  if (!status.ok()) {
+    LOG(ERROR) << "InitSession failed with " << status.error_code() << ": "
+               << status.error_message() << std::endl;
+  }
+
+  // TODO(#6): add CP test code here.
+
+  status = ate->CloseSession();
+  if (!status.ok()) {
+    LOG(ERROR) << "CloseSession failed with " << status.error_code() << ": "
+               << status.error_message() << std::endl;
+  }
+
+  return 0;
+}