1 files changed, 114 insertions, 0 deletions
diff --git a/util/crypto/rsa_private_key.cc b/util/crypto/rsa_private_key.cc
new file mode 100644
index 00000000..7ee12fb9
--- /dev/null
+++ b/util/crypto/rsa_private_key.cc
@@ -0,0 +1,114 @@
+// Copyright 2019 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "util/crypto/rsa_private_key.h"
+
+#include <stdint.h>
+
+#include <algorithm>
+#include <memory>
+#include <utility>
+
+#include "openssl/bn.h"
+#include "openssl/bytestring.h"
+#include "openssl/evp.h"
+#include "openssl/mem.h"
+#include "openssl/rsa.h"
+#include "platform/api/logging.h"
+#include "util/crypto/openssl_util.h"
+
+namespace openscreen {
+RSAPrivateKey::~RSAPrivateKey() = default;
+
+// static
+std::unique_ptr<RSAPrivateKey> RSAPrivateKey::Create(uint16_t num_bits) {
+  OpenSSLErrStackTracer err_tracer(CURRENT_LOCATION);
+
+  bssl::UniquePtr<RSA> rsa_key(RSA_new());
+  bssl::UniquePtr<BIGNUM> exponent(BN_new());
+  if (!rsa_key.get() || !exponent.get() || !BN_set_word(exponent.get(), 65537L))
+    return nullptr;
+
+  if (!RSA_generate_key_ex(rsa_key.get(), num_bits, exponent.get(), nullptr))
+    return nullptr;
+
+  std::unique_ptr<RSAPrivateKey> result(new RSAPrivateKey);
+  result->key_.reset(EVP_PKEY_new());
+  if (!result->key_ || !EVP_PKEY_set1_RSA(result->key_.get(), rsa_key.get()))
+    return nullptr;
+
+  return result;
+}
+
+// static
+std::unique_ptr<RSAPrivateKey> RSAPrivateKey::CreateFromPrivateKeyInfo(
+    const std::vector<uint8_t>& input) {
+  OpenSSLErrStackTracer err_tracer(CURRENT_LOCATION);
+
+  CBS private_key_cbs;
+  CBS_init(&private_key_cbs, input.data(), input.size());
+  bssl::UniquePtr<EVP_PKEY> private_key(
+      EVP_parse_private_key(&private_key_cbs));
+  if (!private_key || CBS_len(&private_key_cbs) != 0 ||
+      EVP_PKEY_id(private_key.get()) != EVP_PKEY_RSA)
+    return nullptr;
+
+  std::unique_ptr<RSAPrivateKey> result(new RSAPrivateKey);
+  result->key_ = std::move(private_key);
+  return result;
+}
+
+// static
+std::unique_ptr<RSAPrivateKey> RSAPrivateKey::CreateFromKey(EVP_PKEY* key) {
+  OSP_DCHECK(key);
+  if (EVP_PKEY_type(key->type) != EVP_PKEY_RSA)
+    return nullptr;
+  std::unique_ptr<RSAPrivateKey> result(new RSAPrivateKey);
+  result->key_ = bssl::UpRef(key);
+  return result;
+}
+
+std::unique_ptr<RSAPrivateKey> RSAPrivateKey::Copy() const {
+  std::unique_ptr<RSAPrivateKey> result(new RSAPrivateKey);
+  bssl::UniquePtr<RSA> rsa(EVP_PKEY_get1_RSA(key_.get()));
+  if (!rsa)
+    return nullptr;
+  result->key_.reset(EVP_PKEY_new());
+  if (!EVP_PKEY_set1_RSA(result->key_.get(), rsa.get()))
+    return nullptr;
+  return result;
+}
+
+bool RSAPrivateKey::ExportPrivateKey(std::vector<uint8_t>* output) const {
+  OpenSSLErrStackTracer err_tracer(CURRENT_LOCATION);
+  uint8_t* der;
+  size_t der_len;
+  bssl::ScopedCBB cbb;
+  if (!CBB_init(cbb.get(), 0) ||
+      !EVP_marshal_private_key(cbb.get(), key_.get()) ||
+      !CBB_finish(cbb.get(), &der, &der_len)) {
+    return false;
+  }
+  output->assign(der, der + der_len);
+  OPENSSL_free(der);
+  return true;
+}
+
+bool RSAPrivateKey::ExportPublicKey(std::vector<uint8_t>* output) const {
+  OpenSSLErrStackTracer err_tracer(CURRENT_LOCATION);
+  uint8_t* der;
+  size_t der_len;
+  bssl::ScopedCBB cbb;
+  if (!CBB_init(cbb.get(), 0) ||
+      !EVP_marshal_public_key(cbb.get(), key_.get()) ||
+      !CBB_finish(cbb.get(), &der, &der_len)) {
+    return false;
+  }
+  output->assign(der, der + der_len);
+  OPENSSL_free(der);
+  return true;
+}
+
+RSAPrivateKey::RSAPrivateKey() = default;
+}  // namespace openscreen