remove ssl_verify flag from client API, always use peer verify mode

webcc/client.cc

@@ -101,7 +101,7 @@ void Client::DoClose() {
 void Client::AsyncConnect() {
   if (request_->url().scheme() == "https") {
 #if WEBCC_ENABLE_SSL
-    socket_.reset(new SslSocket{ io_context_, ssl_context_, ssl_verify_ });
+    socket_.reset(new SslSocket{ io_context_, ssl_context_ });
     AsyncResolve("443");
 #else
     LOG_ERRO("SSL/HTTPS support is not enabled.");

webcc/client.h

@@ -36,10 +36,6 @@ public:
 
   ~Client() = default;
 
-  void set_ssl_verify(bool ssl_verify) {
-    ssl_verify_ = ssl_verify;
-  }
-
   void set_buffer_size(std::size_t buffer_size) {
     if (buffer_size > 0) {
       buffer_size_ = buffer_size;
@@ -142,9 +138,6 @@ private:
   // The buffer for reading response.
   std::vector<char> buffer_;
 
-  // Verify the certificate of the peer or not (for HTTPS).
-  bool ssl_verify_ = true;
-
   // The size of the buffer for reading response.
   // 0 means default value will be used.
   std::size_t buffer_size_ = kBufferSize;
@@ -166,6 +159,7 @@ private:
   // Progress callback (optional).
   ProgressCallback progress_callback_;
 
+  // Current error.
   Error error_;
 };
 

webcc/client_session.cc

@@ -41,7 +41,7 @@ namespace webcc {
 
 static bool UseSystemCertificateStore(SSL_CTX* ssl_ctx) {
   // NOTE: Cannot use nullptr to replace NULL.
-  HCERTSTORE cert_store = ::CertOpenSystemStoreW(NULL, L"ROOT");
+  HCERTSTORE cert_store = CertOpenSystemStoreW(NULL, L"ROOT");
   if (cert_store == nullptr) {
     LOG_ERRO("Cannot open Windows system certificate store.");
     return false;
@@ -71,17 +71,15 @@ static bool UseSystemCertificateStore(SSL_CTX* ssl_ctx) {
 #endif  // defined(_WIN32) || defined(_WIN64)
 #endif  // WEBCC_ENABLE_SSL
 
-ClientSession::ClientSession(bool ssl_verify, std::size_t buffer_size)
+ClientSession::ClientSession(std::size_t buffer_size)
     : work_guard_(boost::asio::make_work_guard(io_context_)),
 #if WEBCC_ENABLE_SSL
       ssl_context_(boost::asio::ssl::context::sslv23),
 #endif
-      ssl_verify_(ssl_verify), buffer_size_(buffer_size) {
+      buffer_size_(buffer_size) {
 #if WEBCC_ENABLE_SSL
 #if (defined(_WIN32) || defined(_WIN64))
-  // if (ssl_verify_) {
     UseSystemCertificateStore(ssl_context_.native_handle());
-  // }
 #else
   // Use the default paths for finding CA certificates.
   ssl_context_.set_default_verify_paths();
@@ -252,7 +250,6 @@ ResponsePtr ClientSession::DoSend(RequestPtr request, bool stream,
     reuse = true;
   }
 
-  client->set_ssl_verify(ssl_verify_);
   client->set_buffer_size(buffer_size_);
   client->set_connect_timeout(connect_timeout_);
   client->set_read_timeout(read_timeout_);

webcc/client_session.h

@@ -15,12 +15,12 @@
 
 namespace webcc {
 
-// HTTP requests session providing connection-pooling, configuration and more.
+// Client session provides connection-pooling, configuration and more.
-// NOTE: If a session is shared by multiple threads, the requests sent through
+// If a client session is shared by multiple threads, the requests sent through
-//       it will be serialized by using a mutex.
+// it will be serialized by using a mutex.
 class ClientSession {
 public:
-  explicit ClientSession(bool ssl_verify = true, std::size_t buffer_size = 0);
+  explicit ClientSession(std::size_t buffer_size = 0);
 
   ~ClientSession();
 
@@ -45,10 +45,6 @@ public:
     }
   }
 
-  void set_ssl_verify(bool ssl_verify) {
-    ssl_verify_ = ssl_verify;
-  }
-
   void set_buffer_size(std::size_t buffer_size) {
     buffer_size_ = buffer_size;
   }
@@ -140,20 +136,17 @@ private:
   // Timeout (seconds) for reading response.
   int read_timeout_ = 0;
 
-  // Verify the certificate of the peer or not.
-  bool ssl_verify_ = true;
-
   // The size of the buffer for reading response.
   // 0 means default value will be used.
   std::size_t buffer_size_;
 
-  // Keep-Alive client connections.
+  // Persistent (keep-alive) client connections.
   ClientPool pool_;
 
   // Current requested client.
   ClientPtr client_;
 
-  // The mutex to guard the request.
+  // The mutex to serialize the requests.
   std::mutex mutex_;
 };
 

webcc/socket.cc

@@ -60,9 +60,8 @@ bool Socket::Close() {
 namespace ssl = boost::asio::ssl;
 
 SslSocket::SslSocket(boost::asio::io_context& io_context,
-                     ssl::context& ssl_context, bool ssl_verify)
+                     ssl::context& ssl_context)
-    : ssl_socket_(io_context, ssl_context),
+    : ssl_stream_(io_context, ssl_context) {
-      ssl_verify_(ssl_verify) {
 }
 
 void SslSocket::AsyncConnect(const std::string& host,
@@ -70,37 +69,35 @@ void SslSocket::AsyncConnect(const std::string& host,
                              ConnectHandler&& handler) {
   connect_handler_ = std::move(handler);
 
-
+  // Modes `ssl::verify_fail_if_no_peer_cert` and `ssl::verify_client_once` are
-  if (ssl_verify_) {
+  // for server only. `ssl::verify_none` is not secure.
-    ssl_socket_.set_verify_mode(ssl::verify_peer);
+  // See: https://stackoverflow.com/a/12621528
-  } else {
+  ssl_stream_.set_verify_mode(ssl::verify_peer);
-    ssl_socket_.set_verify_mode(ssl::verify_none);
-  }
 
   // ssl::host_name_verification has been added since Boost 1.73 to replace
   // ssl::rfc2818_verification.
 #if BOOST_VERSION < 107300
-  ssl_socket_.set_verify_callback(ssl::rfc2818_verification(host));
+  ssl_stream_.set_verify_callback(ssl::rfc2818_verification(host));
 #else
-  ssl_socket_.set_verify_callback(ssl::host_name_verification(host));
+  ssl_stream_.set_verify_callback(ssl::host_name_verification(host));
 #endif  // BOOST_VERSION < 107300
 
-  boost::asio::async_connect(ssl_socket_.lowest_layer(), endpoints,
+  boost::asio::async_connect(ssl_stream_.lowest_layer(), endpoints,
                              std::bind(&SslSocket::OnConnect, this, _1, _2));
 }
 
 void SslSocket::AsyncWrite(const Payload& payload, WriteHandler&& handler) {
-  boost::asio::async_write(ssl_socket_, payload, std::move(handler));
+  boost::asio::async_write(ssl_stream_, payload, std::move(handler));
 }
 
 void SslSocket::AsyncReadSome(ReadHandler&& handler,
                               std::vector<char>* buffer) {
-  ssl_socket_.async_read_some(boost::asio::buffer(*buffer), std::move(handler));
+  ssl_stream_.async_read_some(boost::asio::buffer(*buffer), std::move(handler));
 }
 
 bool SslSocket::Shutdown() {
   boost::system::error_code ec;
-  ssl_socket_.lowest_layer().shutdown(tcp::socket::shutdown_both, ec);
+  ssl_stream_.lowest_layer().shutdown(tcp::socket::shutdown_both, ec);
 
   if (ec) {
     LOG_WARN("Socket shutdown error (%s)", ec.message().c_str());
@@ -112,7 +109,7 @@ bool SslSocket::Shutdown() {
 
 bool SslSocket::Close() {
   boost::system::error_code ec;
-  ssl_socket_.lowest_layer().close(ec);
+  ssl_stream_.lowest_layer().close(ec);
 
   if (ec) {
     LOG_WARN("Socket close error (%s)", ec.message().c_str());
@@ -132,7 +129,7 @@ void SslSocket::OnConnect(boost::system::error_code ec,
   // Backup endpoint
   endpoint_ = std::move(endpoint);
 
-  ssl_socket_.async_handshake(ssl::stream_base::client,
+  ssl_stream_.async_handshake(ssl::stream_base::client,
                               [this](boost::system::error_code ec) {
     if (ec) {
       LOG_ERRO("Handshake error (%s)", ec.message().c_str());

webcc/socket.h

@@ -72,8 +72,7 @@ private:
 class SslSocket : public SocketBase {
 public:
   SslSocket(boost::asio::io_context& io_context,
-            boost::asio::ssl::context& ssl_context,
+            boost::asio::ssl::context& ssl_context);
-            bool ssl_verify = true);
 
   void AsyncConnect(const std::string& host, const Endpoints& endpoints,
                     ConnectHandler&& handler) override;
@@ -93,10 +92,7 @@ private:
   ConnectHandler connect_handler_;
   boost::asio::ip::tcp::endpoint endpoint_;
 
-  boost::asio::ssl::stream<boost::asio::ip::tcp::socket> ssl_socket_;
+  boost::asio::ssl::stream<boost::asio::ip::tcp::socket> ssl_stream_;
-
-  // Verify the certificate of the peer (remote server) or not.
-  bool ssl_verify_ = true;
 };
 
 #endif  // WEBCC_ENABLE_SSL