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Diffstat (limited to 'comm/third_party/botan/src/lib/tls/asio/asio_stream.h')
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1 files changed, 835 insertions, 0 deletions
diff --git a/comm/third_party/botan/src/lib/tls/asio/asio_stream.h b/comm/third_party/botan/src/lib/tls/asio/asio_stream.h new file mode 100644 index 0000000000..bef95e44a0 --- /dev/null +++ b/comm/third_party/botan/src/lib/tls/asio/asio_stream.h @@ -0,0 +1,835 @@ +/* +* TLS ASIO Stream +* (C) 2018-2020 Jack Lloyd +* 2018-2020 Hannes Rantzsch, Tim Oesterreich, Rene Meusel +* +* Botan is released under the Simplified BSD License (see license.txt) +*/ + +#ifndef BOTAN_ASIO_STREAM_H_ +#define BOTAN_ASIO_STREAM_H_ + +#include <botan/build.h> + +// first version to be compatible with Networking TS (N4656) and boost::beast +#include <boost/version.hpp> +#if BOOST_VERSION >= 106600 + +#include <botan/asio_async_ops.h> +#include <botan/asio_context.h> +#include <botan/asio_error.h> + +#include <botan/tls_callbacks.h> +#include <botan/tls_channel.h> +#include <botan/tls_client.h> +#include <botan/tls_magic.h> +#include <botan/tls_server.h> + +// We need to define BOOST_ASIO_DISABLE_SERIAL_PORT before any asio imports. Otherwise asio will include <termios.h>, +// which interferes with Botan's amalgamation by defining macros like 'B0' and 'FF1'. +#define BOOST_ASIO_DISABLE_SERIAL_PORT +#include <boost/asio.hpp> +#include <boost/beast/core.hpp> + +#include <algorithm> +#include <memory> +#include <type_traits> + +namespace Botan { +namespace TLS { + +/** + * @brief boost::asio compatible SSL/TLS stream + * + * @tparam StreamLayer type of the next layer, usually a network socket + * @tparam ChannelT type of the native_handle, defaults to Botan::TLS::Channel, only needed for testing purposes + */ +template <class StreamLayer, class ChannelT = Channel> +class Stream + { + public: + //! \name construction + //! @{ + + /** + * @brief Construct a new Stream + * + * @param context The context parameter is used to set up the underlying native handle. Using code is + * responsible for lifetime management of the context and must ensure that it is available for the + * lifetime of the stream. + * @param args Arguments to be forwarded to the construction of the next layer. + */ + template <typename... Args> + explicit Stream(Context& context, Args&& ... args) + : m_context(context) + , m_nextLayer(std::forward<Args>(args)...) + , m_core(*this) + , m_shutdown_received(false) + , m_input_buffer_space(MAX_CIPHERTEXT_SIZE, '\0') + , m_input_buffer(m_input_buffer_space.data(), m_input_buffer_space.size()) + {} + + /** + * @brief Construct a new Stream + * + * Convenience overload for boost::asio::ssl::stream compatibility. + * + * @param arg This argument is forwarded to the construction of the next layer. + * @param context The context parameter is used to set up the underlying native handle. Using code is + * responsible for lifetime management of the context and must ensure that is available for the + * lifetime of the stream. + */ + template <typename Arg> + explicit Stream(Arg&& arg, Context& context) + : m_context(context) + , m_nextLayer(std::forward<Arg>(arg)) + , m_core(*this) + , m_shutdown_received(false) + , m_input_buffer_space(MAX_CIPHERTEXT_SIZE, '\0') + , m_input_buffer(m_input_buffer_space.data(), m_input_buffer_space.size()) + {} + + virtual ~Stream() = default; + + Stream(Stream&& other) = default; + Stream& operator=(Stream&& other) = default; + + Stream(const Stream& other) = delete; + Stream& operator=(const Stream& other) = delete; + + //! @} + //! \name boost::asio accessor methods + //! @{ + + using next_layer_type = typename std::remove_reference<StreamLayer>::type; + + const next_layer_type& next_layer() const { return m_nextLayer; } + next_layer_type& next_layer() { return m_nextLayer; } + +#if BOOST_VERSION >= 107000 + /* + * From Boost 1.70 onwards Beast types no longer provide public access to the member function `lowest_layer()`. + * Instead, the new free-standing functions in Beast need to be used. + * See also: https://github.com/boostorg/beast/commit/6a658b5c3a36f8d58334f8b6582c01c3e87768ae + */ + using lowest_layer_type = typename boost::beast::lowest_layer_type<StreamLayer>; + + lowest_layer_type& lowest_layer() { return boost::beast::get_lowest_layer(m_nextLayer); } + const lowest_layer_type& lowest_layer() const { return boost::beast::get_lowest_layer(m_nextLayer); } +#else + using lowest_layer_type = typename next_layer_type::lowest_layer_type; + + lowest_layer_type& lowest_layer() { return m_nextLayer.lowest_layer(); } + const lowest_layer_type& lowest_layer() const { return m_nextLayer.lowest_layer(); } +#endif + + using executor_type = typename next_layer_type::executor_type; + executor_type get_executor() noexcept { return m_nextLayer.get_executor(); } + + using native_handle_type = typename std::add_pointer<ChannelT>::type; + native_handle_type native_handle() + { + if(m_native_handle == nullptr) + { throw Invalid_State("Invalid handshake state"); } + return m_native_handle.get(); + } + + //! @} + //! \name configuration and callback setters + //! @{ + + /** + * @brief Override the tls_verify_cert_chain callback + * + * This changes the verify_callback in the stream's TLS::Context, and hence the tls_verify_cert_chain callback + * used in the handshake. + * Using this function is equivalent to setting the callback via @see Botan::TLS::Context::set_verify_callback + * + * @note This function should only be called before initiating the TLS handshake + */ + void set_verify_callback(Context::Verify_Callback callback) + { + m_context.set_verify_callback(std::move(callback)); + } + + /** + * @brief Compatibility overload of @ref set_verify_callback + * + * @param callback the callback implementation + * @param ec This parameter is unused. + */ + void set_verify_callback(Context::Verify_Callback callback, boost::system::error_code& ec) + { + BOTAN_UNUSED(ec); + m_context.set_verify_callback(std::move(callback)); + } + + //! @throws Not_Implemented + void set_verify_depth(int depth) + { + BOTAN_UNUSED(depth); + throw Not_Implemented("set_verify_depth is not implemented"); + } + + /** + * Not Implemented. + * @param depth the desired verification depth + * @param ec Will be set to `Botan::ErrorType::NotImplemented` + */ + void set_verify_depth(int depth, boost::system::error_code& ec) + { + BOTAN_UNUSED(depth); + ec = Botan::ErrorType::NotImplemented; + } + + //! @throws Not_Implemented + template <typename verify_mode> + void set_verify_mode(verify_mode v) + { + BOTAN_UNUSED(v); + throw Not_Implemented("set_verify_mode is not implemented"); + } + + /** + * Not Implemented. + * @param v the desired verify mode + * @param ec Will be set to `Botan::ErrorType::NotImplemented` + */ + template <typename verify_mode> + void set_verify_mode(verify_mode v, boost::system::error_code& ec) + { + BOTAN_UNUSED(v); + ec = Botan::ErrorType::NotImplemented; + } + + //! @} + //! \name handshake methods + //! @{ + + /** + * @brief Performs SSL handshaking. + * + * The function call will block until handshaking is complete or an error occurs. + * + * @param side The type of handshaking to be performed, i.e. as a client or as a server. + * @throws boost::system::system_error if error occured + */ + void handshake(Connection_Side side) + { + boost::system::error_code ec; + handshake(side, ec); + boost::asio::detail::throw_error(ec, "handshake"); + } + + /** + * @brief Performs SSL handshaking. + * + * The function call will block until handshaking is complete or an error occurs. + * + * @param side The type of handshaking to be performed, i.e. as a client or as a server. + * @param ec Set to indicate what error occurred, if any. + */ + void handshake(Connection_Side side, boost::system::error_code& ec) + { + setup_native_handle(side, ec); + + if(side == CLIENT) + { + // send client hello, which was written to the send buffer on client instantiation + send_pending_encrypted_data(ec); + } + + while(!native_handle()->is_active() && !ec) + { + boost::asio::const_buffer read_buffer{input_buffer().data(), m_nextLayer.read_some(input_buffer(), ec)}; + if(ec) + { return; } + + process_encrypted_data(read_buffer, ec); + + send_pending_encrypted_data(ec); + } + } + + /** + * @brief Starts an asynchronous SSL handshake. + * + * This function call always returns immediately. + * + * @param side The type of handshaking to be performed, i.e. as a client or as a server. + * @param handler The handler to be called when the handshake operation completes. + * The equivalent function signature of the handler must be: void(boost::system::error_code) + */ + template <typename HandshakeHandler> + auto async_handshake(Connection_Side side, HandshakeHandler&& handler) -> + BOOST_ASIO_INITFN_RESULT_TYPE(HandshakeHandler, void(boost::system::error_code)) + { + BOOST_ASIO_HANDSHAKE_HANDLER_CHECK(HandshakeHandler, handler) type_check; + + boost::system::error_code ec; + setup_native_handle(side, ec); + // If ec is set by setup_native_handle, the AsyncHandshakeOperation created below will do nothing but call the + // handler with the error_code set appropriately - no need to early return here. + + boost::asio::async_completion<HandshakeHandler, void(boost::system::error_code)> init(handler); + + detail::AsyncHandshakeOperation<typename std::decay<HandshakeHandler>::type, Stream> + op{std::move(init.completion_handler), *this, ec}; + + return init.result.get(); + } + + //! @throws Not_Implemented + template <typename ConstBufferSequence, typename BufferedHandshakeHandler> + BOOST_ASIO_INITFN_RESULT_TYPE(BufferedHandshakeHandler, + void(boost::system::error_code, std::size_t)) + async_handshake(Connection_Side side, const ConstBufferSequence& buffers, + BufferedHandshakeHandler&& handler) + { + BOTAN_UNUSED(side, buffers, handler); + BOOST_ASIO_HANDSHAKE_HANDLER_CHECK(BufferedHandshakeHandler, handler) type_check; + throw Not_Implemented("buffered async handshake is not implemented"); + } + + //! @} + //! \name shutdown methods + //! @{ + + /** + * @brief Shut down SSL on the stream. + * + * This function is used to shut down SSL on the stream. The function call will block until SSL has been shut down + * or an error occurs. Note that this will not close the lowest layer. + * + * Note that this can be used in reaction of a received shutdown alert from the peer. + * + * @param ec Set to indicate what error occured, if any. + */ + void shutdown(boost::system::error_code& ec) + { + try_with_error_code([&] + { + native_handle()->close(); + }, ec); + + send_pending_encrypted_data(ec); + } + + /** + * @brief Shut down SSL on the stream. + * + * This function is used to shut down SSL on the stream. The function call will block until SSL has been shut down + * or an error occurs. Note that this will not close the lowest layer. + * + * Note that this can be used in reaction of a received shutdown alert from the peer. + * + * @throws boost::system::system_error if error occured + */ + void shutdown() + { + boost::system::error_code ec; + shutdown(ec); + boost::asio::detail::throw_error(ec, "shutdown"); + } + + private: + /** + * @brief Internal wrapper type to adapt the expected signature of `async_shutdown` to the completion handler + * signature of `AsyncWriteOperation`. + * + * This is boilerplate to ignore the `size_t` parameter that is passed to the completion handler of + * `AsyncWriteOperation`. Note that it needs to retain the wrapped handler's executor. + */ + template <typename Handler, typename Executor> + struct Wrapper + { + void operator()(boost::system::error_code ec, std::size_t) + { + handler(ec); + } + + using executor_type = boost::asio::associated_executor_t<Handler, Executor>; + + executor_type get_executor() const noexcept + { + return boost::asio::get_associated_executor(handler, io_executor); + } + + using allocator_type = boost::asio::associated_allocator_t<Handler>; + + allocator_type get_allocator() const noexcept + { + return boost::asio::get_associated_allocator(handler); + } + + Handler handler; + Executor io_executor; + }; + + public: + /** + * @brief Asynchronously shut down SSL on the stream. + * + * This function call always returns immediately. + * + * Note that this can be used in reaction of a received shutdown alert from the peer. + * + * @param handler The handler to be called when the shutdown operation completes. + * The equivalent function signature of the handler must be: void(boost::system::error_code) + */ + template <typename ShutdownHandler> + void async_shutdown(ShutdownHandler&& handler) + { + boost::system::error_code ec; + try_with_error_code([&] + { + native_handle()->close(); + }, ec); + // If ec is set by native_handle->close(), the AsyncWriteOperation created below will do nothing but call the + // handler with the error_code set appropriately - no need to early return here. + + using ShutdownHandlerWrapper = Wrapper<ShutdownHandler, typename Stream::executor_type>; + + ShutdownHandlerWrapper w{std::forward<ShutdownHandler>(handler), get_executor()}; + BOOST_ASIO_SHUTDOWN_HANDLER_CHECK(ShutdownHandler, w) type_check; + + boost::asio::async_completion<ShutdownHandlerWrapper, void(boost::system::error_code, std::size_t)> + init(w); + + detail::AsyncWriteOperation<typename std::decay<ShutdownHandlerWrapper>::type, Stream> + op{std::move(init.completion_handler), *this, boost::asio::buffer_size(send_buffer())}; + + return init.result.get(); + } + + //! @} + //! \name I/O methods + //! @{ + + /** + * @brief Read some data from the stream. + * + * The function call will block until one or more bytes of data has been read successfully, or until an error + * occurs. + * + * @param buffers The buffers into which the data will be read. + * @param ec Set to indicate what error occurred, if any. Specifically, StreamTruncated will be set if the peer + * has closed the connection but did not properly shut down the SSL connection. + * @return The number of bytes read. Returns 0 if an error occurred. + */ + template <typename MutableBufferSequence> + std::size_t read_some(const MutableBufferSequence& buffers, + boost::system::error_code& ec) + { + if(has_received_data()) + { return copy_received_data(buffers); } + + boost::asio::const_buffer read_buffer{input_buffer().data(), m_nextLayer.read_some(input_buffer(), ec)}; + if(ec) + { return 0; } + + process_encrypted_data(read_buffer, ec); + + if(ec) // something went wrong in process_encrypted_data() + { return 0; } + + if(shutdown_received()) + { + // we just received a 'close_notify' from the peer and don't expect any more data + ec = boost::asio::error::eof; + } + else if(ec == boost::asio::error::eof) + { + // we did not expect this disconnection from the peer + ec = StreamError::StreamTruncated; + } + + return !ec ? copy_received_data(buffers) : 0; + } + + /** + * @brief Read some data from the stream. + * + * The function call will block until one or more bytes of data has been read successfully, or until an error + * occurs. + * + * @param buffers The buffers into which the data will be read. + * @return The number of bytes read. Returns 0 if an error occurred. + * @throws boost::system::system_error if error occured + */ + template <typename MutableBufferSequence> + std::size_t read_some(const MutableBufferSequence& buffers) + { + boost::system::error_code ec; + auto const n = read_some(buffers, ec); + boost::asio::detail::throw_error(ec, "read_some"); + return n; + } + + /** + * @brief Write some data to the stream. + * + * The function call will block until one or more bytes of data has been written successfully, or until an error + * occurs. + * + * @param buffers The data to be written. + * @param ec Set to indicate what error occurred, if any. + * @return The number of bytes processed from the input buffers. + */ + template <typename ConstBufferSequence> + std::size_t write_some(const ConstBufferSequence& buffers, + boost::system::error_code& ec) + { + tls_encrypt(buffers, ec); + send_pending_encrypted_data(ec); + return !ec ? boost::asio::buffer_size(buffers) : 0; + } + + /** + * @brief Write some data to the stream. + * + * The function call will block until one or more bytes of data has been written successfully, or until an error + * occurs. + * + * @param buffers The data to be written. + * @return The number of bytes written. + * @throws boost::system::system_error if error occured + */ + template <typename ConstBufferSequence> + std::size_t write_some(const ConstBufferSequence& buffers) + { + boost::system::error_code ec; + auto const n = write_some(buffers, ec); + boost::asio::detail::throw_error(ec, "write_some"); + return n; + } + + /** + * @brief Start an asynchronous write. The function call always returns immediately. + * + * @param buffers The data to be written. + * @param handler The handler to be called when the write operation completes. Copies will be made of the handler + * as required. The equivalent function signature of the handler must be: + * void(boost::system::error_code, std::size_t) + */ + template <typename ConstBufferSequence, typename WriteHandler> + auto async_write_some(const ConstBufferSequence& buffers, WriteHandler&& handler) -> + BOOST_ASIO_INITFN_RESULT_TYPE(WriteHandler, + void(boost::system::error_code, std::size_t)) + { + BOOST_ASIO_WRITE_HANDLER_CHECK(WriteHandler, handler) type_check; + + boost::asio::async_completion<WriteHandler, void(boost::system::error_code, std::size_t)> init(handler); + + boost::system::error_code ec; + tls_encrypt(buffers, ec); + if(ec) + { + // we cannot be sure how many bytes were committed here so clear the send_buffer and let the + // AsyncWriteOperation call the handler with the error_code set + consume_send_buffer(m_send_buffer.size()); + detail::AsyncWriteOperation<typename std::decay<WriteHandler>::type, Stream> + op{std::move(init.completion_handler), *this, std::size_t(0), ec}; + return init.result.get(); + } + + detail::AsyncWriteOperation<typename std::decay<WriteHandler>::type, Stream> + op{std::move(init.completion_handler), *this, boost::asio::buffer_size(buffers)}; + + return init.result.get(); + } + + /** + * @brief Start an asynchronous read. The function call always returns immediately. + * + * @param buffers The buffers into which the data will be read. Although the buffers object may be copied as + * necessary, ownership of the underlying buffers is retained by the caller, which must guarantee + * that they remain valid until the handler is called. + * @param handler The handler to be called when the read operation completes. The equivalent function signature of + * the handler must be: + * void(boost::system::error_code, std::size_t) + */ + template <typename MutableBufferSequence, typename ReadHandler> + auto async_read_some(const MutableBufferSequence& buffers, ReadHandler&& handler) -> + BOOST_ASIO_INITFN_RESULT_TYPE(ReadHandler, + void(boost::system::error_code, std::size_t)) + { + BOOST_ASIO_READ_HANDLER_CHECK(ReadHandler, handler) type_check; + + boost::asio::async_completion<ReadHandler, void(boost::system::error_code, std::size_t)> init(handler); + + detail::AsyncReadOperation<typename std::decay<ReadHandler>::type, Stream, MutableBufferSequence> + op{std::move(init.completion_handler), *this, buffers}; + return init.result.get(); + } + + //! @} + + //! @brief Indicates whether a close_notify alert has been received from the peer. + bool shutdown_received() const + { + return m_shutdown_received; + } + + protected: + template <class H, class S, class M, class A> friend class detail::AsyncReadOperation; + template <class H, class S, class A> friend class detail::AsyncWriteOperation; + template <class H, class S, class A> friend class detail::AsyncHandshakeOperation; + + /** + * @brief Helper class that implements Botan::TLS::Callbacks + * + * This class is provided to the stream's native_handle (Botan::TLS::Channel) and implements the callback + * functions triggered by the native_handle. + * + * @param receive_buffer reference to the buffer where decrypted data should be placed + * @param send_buffer reference to the buffer where encrypted data should be placed + */ + class StreamCore : public Botan::TLS::Callbacks + { + public: + StreamCore(Stream& stream) : m_stream(stream) {} + + virtual ~StreamCore() = default; + + void tls_emit_data(const uint8_t data[], std::size_t size) override + { + m_stream.m_send_buffer.commit( + boost::asio::buffer_copy(m_stream.m_send_buffer.prepare(size), boost::asio::buffer(data, size)) + ); + } + + void tls_record_received(uint64_t, const uint8_t data[], std::size_t size) override + { + m_stream.m_receive_buffer.commit( + boost::asio::buffer_copy(m_stream.m_receive_buffer.prepare(size), boost::asio::const_buffer(data, size)) + ); + } + + void tls_alert(Botan::TLS::Alert alert) override + { + if(alert.type() == Botan::TLS::Alert::CLOSE_NOTIFY) + { + m_stream.set_shutdown_received(); + // Channel::process_alert will automatically write the corresponding close_notify response to the + // send_buffer and close the native_handle after this function returns. + } + } + + std::chrono::milliseconds tls_verify_cert_chain_ocsp_timeout() const override + { + return std::chrono::milliseconds(1000); + } + + bool tls_session_established(const Botan::TLS::Session&) override + { + // TODO: it should be possible to configure this in the using application (via callback?) + return true; + } + + void tls_verify_cert_chain( + const std::vector<X509_Certificate>& cert_chain, + const std::vector<std::shared_ptr<const OCSP::Response>>& ocsp_responses, + const std::vector<Certificate_Store*>& trusted_roots, + Usage_Type usage, + const std::string& hostname, + const TLS::Policy& policy) override + { + if(m_stream.m_context.has_verify_callback()) + { + m_stream.m_context.get_verify_callback()(cert_chain, ocsp_responses, trusted_roots, usage, hostname, policy); + } + else + { + Callbacks::tls_verify_cert_chain(cert_chain, ocsp_responses, trusted_roots, usage, hostname, policy); + } + } + + private: + Stream& m_stream; + }; + + const boost::asio::mutable_buffer& input_buffer() { return m_input_buffer; } + boost::asio::const_buffer send_buffer() const { return m_send_buffer.data(); } + + //! @brief Check if decrypted data is available in the receive buffer + bool has_received_data() const { return m_receive_buffer.size() > 0; } + + //! @brief Copy decrypted data into the user-provided buffer + template <typename MutableBufferSequence> + std::size_t copy_received_data(MutableBufferSequence buffers) + { + // Note: It would be nice to avoid this buffer copy. This could be achieved by equipping the StreamCore with + // the user's desired target buffer once a read is started, and reading directly into that buffer in tls_record + // received. However, we need to deal with the case that the receive buffer provided by the caller is smaller + // than the decrypted record, so this optimization might not be worth the additional complexity. + const auto copiedBytes = boost::asio::buffer_copy(buffers, m_receive_buffer.data()); + m_receive_buffer.consume(copiedBytes); + return copiedBytes; + } + + //! @brief Check if encrypted data is available in the send buffer + bool has_data_to_send() const { return m_send_buffer.size() > 0; } + + //! @brief Mark bytes in the send buffer as consumed, removing them from the buffer + void consume_send_buffer(std::size_t bytesConsumed) { m_send_buffer.consume(bytesConsumed); } + + // This is a helper construct to allow mocking the native_handle in test code. It is activated by explicitly + // specifying a (mocked) channel type template parameter when constructing the stream and does not attempt to + // instantiate the native_handle. + // Note: once we have C++17 we can achieve this much more elegantly using constexpr if. + template<class T = ChannelT> + typename std::enable_if<!std::is_same<Channel, T>::value>::type + setup_native_handle(Connection_Side, boost::system::error_code&) {} + + /** + * @brief Create the native handle. + * + * Depending on the desired connection side, this function will create a Botan::TLS::Client or a + * Botan::TLS::Server. + * + * @param side The desired connection side (client or server) + * @param ec Set to indicate what error occurred, if any. + */ + template<class T = ChannelT> + typename std::enable_if<std::is_same<Channel, T>::value>::type + setup_native_handle(Connection_Side side, boost::system::error_code& ec) + { + try_with_error_code([&] + { + if(side == CLIENT) + { + m_native_handle = std::unique_ptr<Client>( + new Client(m_core, + m_context.m_session_manager, + m_context.m_credentials_manager, + m_context.m_policy, + m_context.m_rng, + m_context.m_server_info, + Protocol_Version::latest_tls_version())); + } + else + { + m_native_handle = std::unique_ptr<Server>( + new Server(m_core, + m_context.m_session_manager, + m_context.m_credentials_manager, + m_context.m_policy, + m_context.m_rng, + false /* no DTLS */)); + } + }, ec); + } + + /** @brief Synchronously write encrypted data from the send buffer to the next layer. + * + * If this function is called with an error code other than 'Success', it will do nothing and return 0. + * + * @param ec Set to indicate what error occurred, if any. Specifically, StreamTruncated will be set if the peer + * has closed the connection but did not properly shut down the SSL connection. + * @return The number of bytes written. + */ + size_t send_pending_encrypted_data(boost::system::error_code& ec) + { + if(ec) + { return 0; } + + auto writtenBytes = boost::asio::write(m_nextLayer, send_buffer(), ec); + consume_send_buffer(writtenBytes); + + if(ec == boost::asio::error::eof && !shutdown_received()) + { + // transport layer was closed by peer without receiving 'close_notify' + ec = StreamError::StreamTruncated; + } + + return writtenBytes; + } + + /** + * @brief Pass plaintext data to the native handle for processing. + * + * The native handle will then create TLS records and hand them back to the Stream via the tls_emit_data callback. + */ + template <typename ConstBufferSequence> + void tls_encrypt(const ConstBufferSequence& buffers, boost::system::error_code& ec) + { + // NOTE: This is not asynchronous: it encrypts the data synchronously. + // The data encrypted by native_handle()->send() is synchronously stored in the send_buffer of m_core, + // but is not actually written to the wire, yet. + for(auto it = boost::asio::buffer_sequence_begin(buffers); + !ec && it != boost::asio::buffer_sequence_end(buffers); + it++) + { + const boost::asio::const_buffer buffer = *it; + try_with_error_code([&] + { + native_handle()->send(static_cast<const uint8_t*>(buffer.data()), buffer.size()); + }, ec); + } + } + + /** + * @brief Pass encrypted data to the native handle for processing. + * + * If an exception occurs while processing the data, an error code will be set. + * + * @param read_buffer Input buffer containing the encrypted data. + * @param ec Set to indicate what error occurred, if any. + */ + void process_encrypted_data(const boost::asio::const_buffer& read_buffer, boost::system::error_code& ec) + { + try_with_error_code([&] + { + native_handle()->received_data(static_cast<const uint8_t*>(read_buffer.data()), read_buffer.size()); + }, ec); + } + + //! @brief Catch exceptions and set an error_code + template <typename Fun> + void try_with_error_code(Fun f, boost::system::error_code& ec) + { + try + { + f(); + } + catch(const TLS_Exception& e) + { + ec = e.type(); + } + catch(const Botan::Exception& e) + { + ec = e.error_type(); + } + catch(const std::exception&) + { + ec = Botan::ErrorType::Unknown; + } + } + + void set_shutdown_received() + { + m_shutdown_received = true; + } + + Context& m_context; + StreamLayer m_nextLayer; + + boost::beast::flat_buffer m_receive_buffer; + boost::beast::flat_buffer m_send_buffer; + + StreamCore m_core; + std::unique_ptr<ChannelT> m_native_handle; + + bool m_shutdown_received; + + // Buffer space used to read input intended for the core + std::vector<uint8_t> m_input_buffer_space; + const boost::asio::mutable_buffer m_input_buffer; + }; + +} // namespace TLS +} // namespace Botan + +#endif // BOOST_VERSION +#endif // BOTAN_ASIO_STREAM_H_ |