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 *
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 * modification, are permitted provided that the following conditions are
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 * notice, this list of conditions and the following disclaimer.
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 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
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 */

#include <string>

#include <grpc/grpc_security.h>
#include <grpc/support/log.h>

#include <grpc++/credentials.h>

namespace grpc {

Credentials::Credentials(grpc_credentials *c_creds) : creds_(c_creds) {}

Credentials::~Credentials() { grpc_credentials_release(creds_); }
grpc_credentials *Credentials::GetRawCreds() { return creds_; }

std::unique_ptr<Credentials> CredentialsFactory::DefaultCredentials() {
  grpc_credentials *c_creds = grpc_default_credentials_create();
  std::unique_ptr<Credentials> cpp_creds(new Credentials(c_creds));
  return cpp_creds;
}

// Builds SSL Credentials given SSL specific options
std::unique_ptr<Credentials> CredentialsFactory::SslCredentials(
    const SslCredentialsOptions &options) {
  const unsigned char *pem_root_certs =
      options.pem_root_certs.empty() ? nullptr
                                     : reinterpret_cast<const unsigned char *>(
                                           options.pem_root_certs.c_str());
  if (pem_root_certs == nullptr) {
    return std::unique_ptr<Credentials>();
  }
  const unsigned char *pem_private_key =
      options.pem_private_key.empty() ? nullptr
                                      : reinterpret_cast<const unsigned char *>(
                                            options.pem_private_key.c_str());
  const unsigned char *pem_cert_chain =
      options.pem_cert_chain.empty() ? nullptr
                                     : reinterpret_cast<const unsigned char *>(
                                           options.pem_cert_chain.c_str());

  grpc_credentials *c_creds = grpc_ssl_credentials_create(
      pem_root_certs, options.pem_root_certs.size(), pem_private_key,
      options.pem_private_key.size(), pem_cert_chain,
      options.pem_cert_chain.size());
  std::unique_ptr<Credentials> cpp_creds(
      c_creds == nullptr ? nullptr : new Credentials(c_creds));
  return cpp_creds;
}

// Builds credentials for use when running in GCE
std::unique_ptr<Credentials> CredentialsFactory::ComputeEngineCredentials() {
  grpc_credentials *c_creds = grpc_compute_engine_credentials_create();
  std::unique_ptr<Credentials> cpp_creds(
      c_creds == nullptr ? nullptr : new Credentials(c_creds));
  return cpp_creds;
}

// Builds service account credentials.
std::unique_ptr<Credentials> CredentialsFactory::ServiceAccountCredentials(
    const grpc::string &json_key, const grpc::string &scope,
    std::chrono::seconds token_lifetime) {
  gpr_timespec lifetime = gpr_time_from_seconds(
      token_lifetime.count() > 0 ? token_lifetime.count() : 0);
  grpc_credentials *c_creds = grpc_service_account_credentials_create(
      json_key.c_str(), scope.c_str(), lifetime);
  std::unique_ptr<Credentials> cpp_creds(
      c_creds == nullptr ? nullptr : new Credentials(c_creds));
  return cpp_creds;
}

// Builds IAM credentials.
std::unique_ptr<Credentials> CredentialsFactory::IAMCredentials(
    const grpc::string &authorization_token,
    const grpc::string &authority_selector) {
  grpc_credentials *c_creds = grpc_iam_credentials_create(
      authorization_token.c_str(), authority_selector.c_str());
  std::unique_ptr<Credentials> cpp_creds(
      c_creds == nullptr ? nullptr : new Credentials(c_creds));
  return cpp_creds;
}

// Combines two credentials objects into a composite credentials.
std::unique_ptr<Credentials> CredentialsFactory::ComposeCredentials(
    const std::unique_ptr<Credentials> &creds1,
    const std::unique_ptr<Credentials> &creds2) {
  // Note that we are not saving unique_ptrs to the two credentials
  // passed in here. This is OK because the underlying C objects (i.e.,
  // creds1 and creds2) into grpc_composite_credentials_create will see their
  // refcounts incremented.
  grpc_credentials *c_creds = grpc_composite_credentials_create(
      creds1->GetRawCreds(), creds2->GetRawCreds());
  std::unique_ptr<Credentials> cpp_creds(
      c_creds == nullptr ? nullptr : new Credentials(c_creds));
  return cpp_creds;
}

}  // namespace grpc