testing/boringssl_utils.cc

// Copyright 2026 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 "testing/boringssl_utils.h"

#include <cstdint>
#include <string>

#include "absl/base/nullability.h"
#include "absl/log/check.h"
#include "absl/log/die_if_null.h"
#include "absl/strings/string_view.h"
#include "openssl/base.h"
#include "openssl/bio.h"
#include "openssl/bytestring.h"
#include "openssl/mem.h"
#include "openssl/obj.h"
#include "openssl/pem.h"
#include "openssl/x509.h"

namespace credentio {

bssl::UniquePtr<X509> absl_nullable PemToCertificate(absl::string_view pem) {
  bssl::UniquePtr<BIO> bio(
      BIO_new_mem_buf(const_cast<char*>(pem.data()), pem.size()));
  X509* x509 = PEM_read_bio_X509(bio.get(), nullptr /* existing key */,
                                 nullptr /* password callback */,
                                 nullptr /* password */);
  return bssl::UniquePtr<X509>(x509);
}

bssl::UniquePtr<EVP_PKEY> absl_nullable PemToKey(absl::string_view pem) {
  bssl::UniquePtr<BIO> bio(
      BIO_new_mem_buf(const_cast<char*>(pem.data()), pem.size()));
  EVP_PKEY* pkey = PEM_read_bio_PrivateKey(
      bio.get(), nullptr /* existing key */, nullptr /* password callback */,
      nullptr /* password */);
  return bssl::UniquePtr<EVP_PKEY>(pkey);
}

std::string PemToDer(absl::string_view pem) {
  bssl::UniquePtr<BIO> bio(ABSL_DIE_IF_NULL(
      BIO_new_mem_buf(const_cast<char*>(pem.data()), pem.size())));

  char* name;
  char* header;
  uint8_t* data;
  long len;  // NOLINT: Can't use `int64_t` because on ARM that becomes long
             // long which is incompatible with `PEM_read_bio(...)`.
  CHECK(PEM_read_bio(bio.get(), &name, &header, &data, &len));
  // Smart pointers for clean-up only.
  bssl::UniquePtr<char> name_uniq(name);
  bssl::UniquePtr<char> header_uniq(header);
  bssl::UniquePtr<uint8_t> data_uniq(data);

  return std::string(reinterpret_cast<const char*>(data), len);
}

}  // namespace credentio