ceph/src/boost/libs/beast/example/http/client/coro-ssl/http_client_coro_ssl.cpp

   1 //
   2 // Copyright (c) 2016-2017 Vinnie Falco (vinnie dot falco at gmail dot com)
   3 //
   4 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   5 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 //
   7 // Official repository: https://github.com/boostorg/beast
   8 //
   9
  10 //------------------------------------------------------------------------------
  11 //
  12 // Example: HTTP SSL client, coroutine
  13 //
  14 //------------------------------------------------------------------------------
  15
  16 #include "example/common/root_certificates.hpp"
  17
  18 #include <boost/beast/core.hpp>
  19 #include <boost/beast/http.hpp>
  20 #include <boost/beast/version.hpp>
  21 #include <boost/asio/connect.hpp>
  22 #include <boost/asio/spawn.hpp>
  23 #include <boost/asio/ip/tcp.hpp>
  24 #include <boost/asio/ssl/error.hpp>
  25 #include <boost/asio/ssl/stream.hpp>
  26 #include <cstdlib>
  27 #include <functional>
  28 #include <iostream>
  29 #include <string>
  30
  31 using tcp = boost::asio::ip::tcp;       // from <boost/asio/ip/tcp.hpp>
  32 namespace ssl = boost::asio::ssl;       // from <boost/asio/ssl.hpp>
  33 namespace http = boost::beast::http;    // from <boost/beast/http.hpp>
  34
  35 //------------------------------------------------------------------------------
  36
  37 // Report a failure
  38 void
  39 fail(boost::system::error_code ec, char const* what)
  40 {
  41     std::cerr << what << ": " << ec.message() << "\n";
  42 }
  43
  44 // Performs an HTTP GET and prints the response
  45 void
  46 do_session(
  47     std::string const& host,
  48     std::string const& port,
  49     std::string const& target,
  50     int version,
  51     boost::asio::io_context& ioc,
  52     ssl::context& ctx,
  53     boost::asio::yield_context yield)
  54 {
  55     boost::system::error_code ec;
  56
  57     // These objects perform our I/O
  58     tcp::resolver resolver{ioc};
  59     ssl::stream<tcp::socket> stream{ioc, ctx};
  60
  61     // Set SNI Hostname (many hosts need this to handshake successfully)
  62     if(! SSL_set_tlsext_host_name(stream.native_handle(), host.c_str()))
  63     {
  64         ec.assign(static_cast<int>(::ERR_get_error()), boost::asio::error::get_ssl_category());
  65         std::cerr << ec.message() << "\n";
  66         return;
  67     }
  68
  69     // Look up the domain name
  70     auto const results = resolver.async_resolve(host, port, yield[ec]);
  71     if(ec)
  72         return fail(ec, "resolve");
  73
  74     // Make the connection on the IP address we get from a lookup
  75     boost::asio::async_connect(stream.next_layer(), results.begin(), results.end(), yield[ec]);
  76     if(ec)
  77         return fail(ec, "connect");
  78
  79     // Perform the SSL handshake
  80     stream.async_handshake(ssl::stream_base::client, yield[ec]);
  81     if(ec)
  82         return fail(ec, "handshake");
  83
  84     // Set up an HTTP GET request message
  85     http::request<http::string_body> req{http::verb::get, target, version};
  86     req.set(http::field::host, host);
  87     req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
  88
  89     // Send the HTTP request to the remote host
  90     http::async_write(stream, req, yield[ec]);
  91     if(ec)
  92         return fail(ec, "write");
  93
  94     // This buffer is used for reading and must be persisted
  95     boost::beast::flat_buffer b;
  96
  97     // Declare a container to hold the response
  98     http::response<http::dynamic_body> res;
  99
 100     // Receive the HTTP response
 101     http::async_read(stream, b, res, yield[ec]);
 102     if(ec)
 103         return fail(ec, "read");
 104
 105     // Write the message to standard out
 106     std::cout << res << std::endl;
 107
 108     // Gracefully close the stream
 109     stream.async_shutdown(yield[ec]);
 110     if(ec == boost::asio::error::eof)
 111     {
 112         // Rationale:
 113         // http://stackoverflow.com/questions/25587403/boost-asio-ssl-async-shutdown-always-finishes-with-an-error
 114         ec.assign(0, ec.category());
 115     }
 116     if(ec)
 117         return fail(ec, "shutdown");
 118
 119     // If we get here then the connection is closed gracefully
 120 }
 121
 122 //------------------------------------------------------------------------------
 123
 124 int main(int argc, char** argv)
 125 {
 126     // Check command line arguments.
 127     if(argc != 4 && argc != 5)
 128     {
 129         std::cerr <<
 130             "Usage: http-client-coro-ssl <host> <port> <target> [<HTTP version: 1.0 or 1.1(default)>]\n" <<
 131             "Example:\n" <<
 132             "    http-client-coro-ssl www.example.com 443 /\n" <<
 133             "    http-client-coro-ssl www.example.com 443 / 1.0\n";
 134         return EXIT_FAILURE;
 135     }
 136     auto const host = argv[1];
 137     auto const port = argv[2];
 138     auto const target = argv[3];
 139     int version = argc == 5 && !std::strcmp("1.0", argv[4]) ? 10 : 11;
 140
 141     // The io_context is required for all I/O
 142     boost::asio::io_context ioc;
 143
 144     // The SSL context is required, and holds certificates
 145     ssl::context ctx{ssl::context::sslv23_client};
 146
 147     // This holds the root certificate used for verification
 148     load_root_certificates(ctx);
 149
 150     // Launch the asynchronous operation
 151     boost::asio::spawn(ioc, std::bind(
 152         &do_session,
 153         std::string(host),
 154         std::string(port),
 155         std::string(target),
 156         version,
 157         std::ref(ioc),
 158         std::ref(ctx),
 159         std::placeholders::_1));
 160
 161     // Run the I/O service. The call will return when
 162     // the get operation is complete.
 163     ioc.run();
 164
 165     return EXIT_SUCCESS;
 166 }