1 //
2 // Copyright (c) 2016-2019 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, synchronous
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/ssl.hpp>
21 #include <boost/beast/version.hpp>
22 #include <boost/asio/connect.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 <iostream>
28 #include <string>
29
30 namespace beast = boost::beast; // from <boost/beast.hpp>
31 namespace http = beast::http; // from <boost/beast/http.hpp>
32 namespace net = boost::asio; // from <boost/asio.hpp>
33 namespace ssl = net::ssl; // from <boost/asio/ssl.hpp>
34 using tcp = net::ip::tcp; // from <boost/asio/ip/tcp.hpp>
35
36 // Performs an HTTP GET and prints the response
main(int argc,char ** argv)37 int main(int argc, char** argv)
38 {
39 try
40 {
41 // Check command line arguments.
42 if(argc != 4 && argc != 5)
43 {
44 std::cerr <<
45 "Usage: http-client-sync-ssl <host> <port> <target> [<HTTP version: 1.0 or 1.1(default)>]\n" <<
46 "Example:\n" <<
47 " http-client-sync-ssl www.example.com 443 /\n" <<
48 " http-client-sync-ssl www.example.com 443 / 1.0\n";
49 return EXIT_FAILURE;
50 }
51 auto const host = argv[1];
52 auto const port = argv[2];
53 auto const target = argv[3];
54 int version = argc == 5 && !std::strcmp("1.0", argv[4]) ? 10 : 11;
55
56 // The io_context is required for all I/O
57 net::io_context ioc;
58
59 // The SSL context is required, and holds certificates
60 ssl::context ctx(ssl::context::tlsv12_client);
61
62 // This holds the root certificate used for verification
63 load_root_certificates(ctx);
64
65 // Verify the remote server's certificate
66 ctx.set_verify_mode(ssl::verify_peer);
67
68 // These objects perform our I/O
69 tcp::resolver resolver(ioc);
70 beast::ssl_stream<beast::tcp_stream> stream(ioc, ctx);
71
72 // Set SNI Hostname (many hosts need this to handshake successfully)
73 if(! SSL_set_tlsext_host_name(stream.native_handle(), host))
74 {
75 beast::error_code ec{static_cast<int>(::ERR_get_error()), net::error::get_ssl_category()};
76 throw beast::system_error{ec};
77 }
78
79 // Look up the domain name
80 auto const results = resolver.resolve(host, port);
81
82 // Make the connection on the IP address we get from a lookup
83 beast::get_lowest_layer(stream).connect(results);
84
85 // Perform the SSL handshake
86 stream.handshake(ssl::stream_base::client);
87
88 // Set up an HTTP GET request message
89 http::request<http::string_body> req{http::verb::get, target, version};
90 req.set(http::field::host, host);
91 req.set(http::field::user_agent, BOOST_BEAST_VERSION_STRING);
92
93 // Send the HTTP request to the remote host
94 http::write(stream, req);
95
96 // This buffer is used for reading and must be persisted
97 beast::flat_buffer buffer;
98
99 // Declare a container to hold the response
100 http::response<http::dynamic_body> res;
101
102 // Receive the HTTP response
103 http::read(stream, buffer, res);
104
105 // Write the message to standard out
106 std::cout << res << std::endl;
107
108 // Gracefully close the stream
109 beast::error_code ec;
110 stream.shutdown(ec);
111 if(ec == net::error::eof)
112 {
113 // Rationale:
114 // http://stackoverflow.com/questions/25587403/boost-asio-ssl-async-shutdown-always-finishes-with-an-error
115 ec = {};
116 }
117 if(ec)
118 throw beast::system_error{ec};
119
120 // If we get here then the connection is closed gracefully
121 }
122 catch(std::exception const& e)
123 {
124 std::cerr << "Error: " << e.what() << std::endl;
125 return EXIT_FAILURE;
126 }
127 return EXIT_SUCCESS;
128 }
129