diff options
Diffstat (limited to 'webserver.cpp')
| -rw-r--r-- | webserver.cpp | 547 |
1 files changed, 2 insertions, 545 deletions
diff --git a/webserver.cpp b/webserver.cpp index d2d1bee..4b6a89c 100644 --- a/webserver.cpp +++ b/webserver.cpp @@ -1,549 +1,6 @@ -#include "server_certificate.h" - -#include <boost/beast/core.hpp> -#include <boost/beast/http.hpp> -#include <boost/beast/ssl.hpp> -#include <boost/beast/version.hpp> -#include <boost/asio/dispatch.hpp> -#include <boost/asio/strand.hpp> -#include <boost/config.hpp> -#include <algorithm> -#include <cstdlib> -#include <functional> -#include <iostream> -#include <memory> -#include <string> -#include <thread> -#include <vector> - -namespace beast = boost::beast; // from <boost/beast.hpp> -namespace http = beast::http; // from <boost/beast/http.hpp> -namespace net = boost::asio; // from <boost/asio.hpp> -namespace ssl = boost::asio::ssl; // from <boost/asio/ssl.hpp> -using tcp = boost::asio::ip::tcp; // from <boost/asio/ip/tcp.hpp> - -// Return a reasonable mime type based on the extension of a file. -beast::string_view -mime_type(beast::string_view path) -{ - using beast::iequals; - auto const ext = [&path] - { - auto const pos = path.rfind("."); - if(pos == beast::string_view::npos) - return beast::string_view{}; - return path.substr(pos); - }(); - if(iequals(ext, ".htm")) return "text/html"; - if(iequals(ext, ".html")) return "text/html"; - if(iequals(ext, ".php")) return "text/html"; - if(iequals(ext, ".css")) return "text/css"; - if(iequals(ext, ".txt")) return "text/plain"; - if(iequals(ext, ".js")) return "application/javascript"; - if(iequals(ext, ".json")) return "application/json"; - if(iequals(ext, ".xml")) return "application/xml"; - if(iequals(ext, ".swf")) return "application/x-shockwave-flash"; - if(iequals(ext, ".flv")) return "video/x-flv"; - if(iequals(ext, ".png")) return "image/png"; - if(iequals(ext, ".jpe")) return "image/jpeg"; - if(iequals(ext, ".jpeg")) return "image/jpeg"; - if(iequals(ext, ".jpg")) return "image/jpeg"; - if(iequals(ext, ".gif")) return "image/gif"; - if(iequals(ext, ".bmp")) return "image/bmp"; - if(iequals(ext, ".ico")) return "image/vnd.microsoft.icon"; - if(iequals(ext, ".tiff")) return "image/tiff"; - if(iequals(ext, ".tif")) return "image/tiff"; - if(iequals(ext, ".svg")) return "image/svg+xml"; - if(iequals(ext, ".svgz")) return "image/svg+xml"; - return "application/text"; -} - -// Append an HTTP rel-path to a local filesystem path. -// The returned path is normalized for the platform. -std::string -path_cat( - beast::string_view base, - beast::string_view path) -{ - if(base.empty()) - return std::string(path); - std::string result(base); -#ifdef BOOST_MSVC - char constexpr path_separator = '\\'; - if(result.back() == path_separator) - result.resize(result.size() - 1); - result.append(path.data(), path.size()); - for(auto& c : result) - if(c == '/') - c = path_separator; -#else - char constexpr path_separator = '/'; - if(result.back() == path_separator) - result.resize(result.size() - 1); - result.append(path.data(), path.size()); -#endif - return result; -} - -// This function produces an HTTP response for the given -// request. The type of the response object depends on the -// contents of the request, so the interface requires the -// caller to pass a generic lambda for receiving the response. -template< - class Body, class Allocator, - class Send> -void -handle_request( - beast::string_view doc_root, - http::request<Body, http::basic_fields<Allocator>>&& req, - Send&& send) -{ - // Returns a bad request response - auto const bad_request = - [&req](beast::string_view why) - { - http::response<http::string_body> res{http::status::bad_request, req.version()}; - res.set(http::field::server, BOOST_BEAST_VERSION_STRING); - res.set(http::field::content_type, "text/html"); - res.keep_alive(req.keep_alive()); - res.body() = std::string(why); - res.prepare_payload(); - return res; - }; - - // Returns a not found response - auto const not_found = - [&req](beast::string_view target) - { - http::response<http::string_body> res{http::status::not_found, req.version()}; - res.set(http::field::server, BOOST_BEAST_VERSION_STRING); - res.set(http::field::content_type, "text/html"); - res.keep_alive(req.keep_alive()); - res.body() = "The resource '" + std::string(target) + "' was not found."; - res.prepare_payload(); - return res; - }; - - // Returns a server error response - auto const server_error = - [&req](beast::string_view what) - { - http::response<http::string_body> res{http::status::internal_server_error, req.version()}; - res.set(http::field::server, BOOST_BEAST_VERSION_STRING); - res.set(http::field::content_type, "text/html"); - res.keep_alive(req.keep_alive()); - res.body() = "An error occurred: '" + std::string(what) + "'"; - res.prepare_payload(); - return res; - }; - - // Make sure we can handle the method - if( req.method() != http::verb::get && - req.method() != http::verb::head) - return send(bad_request("Unknown HTTP-method")); - - // Request path must be absolute and not contain "..". - if( req.target().empty() || - req.target()[0] != '/' || - req.target().find("..") != beast::string_view::npos) - return send(bad_request("Illegal request-target")); - - // Build the path to the requested file - std::string path = path_cat(doc_root, req.target()); - if(req.target().back() == '/') - path.append("index.html"); - - // Attempt to open the file - beast::error_code ec; - http::file_body::value_type body; - body.open(path.c_str(), beast::file_mode::scan, ec); - - // Handle the case where the file doesn't exist - if(ec == beast::errc::no_such_file_or_directory) - return send(not_found(req.target())); - - // Handle an unknown error - if(ec) - return send(server_error(ec.message())); - - // Cache the size since we need it after the move - auto const size = body.size(); - - // Respond to HEAD request - if(req.method() == http::verb::head) - { - http::response<http::empty_body> res{http::status::ok, req.version()}; - res.set(http::field::server, BOOST_BEAST_VERSION_STRING); - res.set(http::field::content_type, mime_type(path)); - res.content_length(size); - res.keep_alive(req.keep_alive()); - return send(std::move(res)); - } - - // Respond to GET request - http::response<http::file_body> res{ - std::piecewise_construct, - std::make_tuple(std::move(body)), - std::make_tuple(http::status::ok, req.version())}; - res.set(http::field::server, BOOST_BEAST_VERSION_STRING); - res.set(http::field::content_type, mime_type(path)); - res.content_length(size); - res.keep_alive(req.keep_alive()); - return send(std::move(res)); -} - -//------------------------------------------------------------------------------ - -// Report a failure -void -fail(beast::error_code ec, char const* what) -{ - // ssl::error::stream_truncated, also known as an SSL "short read", - // indicates the peer closed the connection without performing the - // required closing handshake (for example, Google does this to - // improve performance). Generally this can be a security issue, - // but if your communication protocol is self-terminated (as - // it is with both HTTP and WebSocket) then you may simply - // ignore the lack of close_notify. - // - // https://github.com/boostorg/beast/issues/38 - // - // https://security.stackexchange.com/questions/91435/how-to-handle-a-malicious-ssl-tls-shutdown - // - // When a short read would cut off the end of an HTTP message, - // Beast returns the error beast::http::error::partial_message. - // Therefore, if we see a short read here, it has occurred - // after the message has been completed, so it is safe to ignore it. - - if(ec == net::ssl::error::stream_truncated) - return; - - std::cerr << what << ": " << ec.message() << "\n"; -} - -// Handles an HTTP server connection -class session : public std::enable_shared_from_this<session> -{ - // This is the C++11 equivalent of a generic lambda. - // The function object is used to send an HTTP message. - struct send_lambda - { - session& self_; - - explicit - send_lambda(session& self) - : self_(self) - { - } - - template<bool isRequest, class Body, class Fields> - void - operator()(http::message<isRequest, Body, Fields>&& msg) const - { - // The lifetime of the message has to extend - // for the duration of the async operation so - // we use a shared_ptr to manage it. - auto sp = std::make_shared< - http::message<isRequest, Body, Fields>>(std::move(msg)); - - // Store a type-erased version of the shared - // pointer in the class to keep it alive. - self_.res_ = sp; - - // Write the response - http::async_write( - self_.stream_, - *sp, - beast::bind_front_handler( - &session::on_write, - self_.shared_from_this(), - sp->need_eof())); - } - }; - - beast::ssl_stream<beast::tcp_stream> stream_; - beast::flat_buffer buffer_; - std::shared_ptr<std::string const> doc_root_; - http::request<http::string_body> req_; - std::shared_ptr<void> res_; - send_lambda lambda_; - -public: - // Take ownership of the socket - explicit - session( - tcp::socket&& socket, - ssl::context& ctx, - std::shared_ptr<std::string const> const& doc_root) - : stream_(std::move(socket), ctx) - , doc_root_(doc_root) - , lambda_(*this) - { - } - - // Start the asynchronous operation - void - run() - { - // We need to be executing within a strand to perform async operations - // on the I/O objects in this session. Although not strictly necessary - // for single-threaded contexts, this example code is written to be - // thread-safe by default. - net::dispatch( - stream_.get_executor(), - beast::bind_front_handler( - &session::on_run, - shared_from_this())); - } - - void - on_run() - { - // Set the timeout. - beast::get_lowest_layer(stream_).expires_after( - std::chrono::seconds(30)); - - // Perform the SSL handshake - stream_.async_handshake( - ssl::stream_base::server, - beast::bind_front_handler( - &session::on_handshake, - shared_from_this())); - } - - void - on_handshake(beast::error_code ec) - { - if(ec) - return fail(ec, "handshake"); - - do_read(); - } - - void - do_read() - { - // Make the request empty before reading, - // otherwise the operation behavior is undefined. - req_ = {}; - - // Set the timeout. - beast::get_lowest_layer(stream_).expires_after(std::chrono::seconds(30)); - - // Read a request - http::async_read(stream_, buffer_, req_, - beast::bind_front_handler( - &session::on_read, - shared_from_this())); - } - - void - on_read( - beast::error_code ec, - std::size_t bytes_transferred) - { - boost::ignore_unused(bytes_transferred); - - // This means they closed the connection - if(ec == http::error::end_of_stream) - return do_close(); - - if(ec) - return fail(ec, "read"); - - // Send the response - handle_request(*doc_root_, std::move(req_), lambda_); - } - - void - on_write( - bool close, - beast::error_code ec, - std::size_t bytes_transferred) - { - boost::ignore_unused(bytes_transferred); - - if(ec) - return fail(ec, "write"); - - if(close) - { - // This means we should close the connection, usually because - // the response indicated the "Connection: close" semantic. - return do_close(); - } - - // We're done with the response so delete it - res_ = nullptr; - - // Read another request - do_read(); - } - - void - do_close() - { - // Set the timeout. - beast::get_lowest_layer(stream_).expires_after(std::chrono::seconds(30)); - - // Perform the SSL shutdown - stream_.async_shutdown( - beast::bind_front_handler( - &session::on_shutdown, - shared_from_this())); - } - - void - on_shutdown(beast::error_code ec) - { - if(ec) - return fail(ec, "shutdown"); - - // At this point the connection is closed gracefully - } -}; - -//------------------------------------------------------------------------------ - -// Accepts incoming connections and launches the sessions -class listener : public std::enable_shared_from_this<listener> -{ - net::io_context& ioc_; - ssl::context& ctx_; - tcp::acceptor acceptor_; - std::shared_ptr<std::string const> doc_root_; - -public: - listener( - net::io_context& ioc, - ssl::context& ctx, - tcp::endpoint endpoint, - std::shared_ptr<std::string const> const& doc_root) - : ioc_(ioc) - , ctx_(ctx) - , acceptor_(ioc) - , doc_root_(doc_root) - { - beast::error_code ec; - - // Open the acceptor - acceptor_.open(endpoint.protocol(), ec); - if(ec) - { - fail(ec, "open"); - return; - } - - // Allow address reuse - acceptor_.set_option(net::socket_base::reuse_address(true), ec); - if(ec) - { - fail(ec, "set_option"); - return; - } - - // Bind to the server address - acceptor_.bind(endpoint, ec); - if(ec) - { - fail(ec, "bind"); - return; - } - - // Start listening for connections - acceptor_.listen( - net::socket_base::max_listen_connections, ec); - if(ec) - { - fail(ec, "listen"); - return; - } - } - - // Start accepting incoming connections - void - run() - { - do_accept(); - } - -private: - void - do_accept() - { - // The new connection gets its own strand - acceptor_.async_accept( - net::make_strand(ioc_), - beast::bind_front_handler( - &listener::on_accept, - shared_from_this())); - } - - void - on_accept(beast::error_code ec, tcp::socket socket) - { - if(ec) - { - fail(ec, "accept"); - } - else - { - // Create the session and run it - std::make_shared<session>( - std::move(socket), - ctx_, - doc_root_)->run(); - } - - // Accept another connection - do_accept(); - } -}; - -//------------------------------------------------------------------------------ +#include "http.h" int main(int argc, char* argv[]) { - // Check command line arguments. - if (argc != 5) - { - std::cerr << - "Usage: http-server-async-ssl <address> <port> <doc_root> <threads>\n" << - "Example:\n" << - " http-server-async-ssl 0.0.0.0 8080 . 1\n"; - return EXIT_FAILURE; - } - auto const address = net::ip::make_address(argv[1]); - auto const port = static_cast<unsigned short>(std::atoi(argv[2])); - auto const doc_root = std::make_shared<std::string>(argv[3]); - auto const threads = std::max<int>(1, std::atoi(argv[4])); - - // The io_context is required for all I/O - net::io_context ioc{threads}; - - // The SSL context is required, and holds certificates - ssl::context ctx{ssl::context::tlsv12}; - - // This holds the self-signed certificate used by the server - load_server_certificate(ctx); - - // Create and launch a listening port - std::make_shared<listener>( - ioc, - ctx, - tcp::endpoint{address, port}, - doc_root)->run(); - - // Run the I/O service on the requested number of threads - std::vector<std::thread> v; - v.reserve(threads - 1); - for(auto i = threads - 1; i > 0; --i) - v.emplace_back( - [&ioc] - { - ioc.run(); - }); - ioc.run(); - - return EXIT_SUCCESS; + return http_server(argc, argv); } |