fix ssl handshake and parsing issues

examples/CMakeLists.txt

@@ -9,33 +9,37 @@ if(UNIX)
 endif()
 
 set(SIMPLE_EXAMPLES
-	concurrency_test
-	client_basics
-	hello_world_server
-	static_file_server
-	file_downloader
-	server_states
-	form_client
-	form_server
-	form_urlencoded_client
-	)
+    concurrency_test
+    client_basics
+    hello_world_server
+    static_file_server
+    file_downloader
+    server_states
+    form_client
+    form_server
+    form_urlencoded_client
+    )
 
 foreach(example ${SIMPLE_EXAMPLES})
-	add_executable(${example} ${example}.cc)
-	target_link_libraries(${example} ${EXAMPLE_LIBS})
-	set_target_properties(${example} PROPERTIES FOLDER "Examples")
+    add_executable(${example} ${example}.cc)
+    target_link_libraries(${example} ${EXAMPLE_LIBS})
+    set_target_properties(${example} PROPERTIES FOLDER "Examples")
 endforeach()
 
 if(WEBCC_ENABLE_SSL)
     add_executable(github_client github_client.cc)
     target_link_libraries(github_client ${EXAMPLE_LIBS} jsoncpp)
-	set_target_properties(github_client PROPERTIES FOLDER "Examples")
+    set_target_properties(github_client PROPERTIES FOLDER "Examples")
+
+    add_executable(google_client google_client.cc)
+    target_link_libraries(google_client ${EXAMPLE_LIBS})
+    set_target_properties(google_client PROPERTIES FOLDER "Examples")
 endif()
 
 if(WIN32)
     add_executable(url_unicode url_unicode.cc encoding.cc encoding.h)
     target_link_libraries(url_unicode ${EXAMPLE_LIBS})
-	set_target_properties(url_unicode PROPERTIES FOLDER "Examples")
+    set_target_properties(url_unicode PROPERTIES FOLDER "Examples")
 endif()
 
 add_subdirectory(book_server)

examples/client_basics.cc

@@ -15,27 +15,24 @@ int main() {
   webcc::ResponsePtr r;
 
   try {
-    r = session.Send(webcc::RequestBuilder{}.
-                     Get("http://httpbin.org/get").
-                     Query("name", "Adam Gu", /*encode*/true).Date()
-                     ());
+    r = session.Send(WEBCC_GET("http://httpbin.org/get")
+                         .Query("name", "Adam Gu", true)
+                         .Date()());
 
     assert(r->status() == webcc::Status::kOK);
     assert(!r->data().empty());
 
-    r = session.Send(webcc::RequestBuilder{}.
-                     Post("http://httpbin.org/post").
-                     Body("{'name'='Adam', 'age'=20}").Json().Utf8()
-                     ());
+    r = session.Send(WEBCC_POST("http://httpbin.org/post")
+                         .Body("{'name'='Adam', 'age'=20}")
+                         .Json()
+                         .Utf8()());
 
     assert(r->status() == webcc::Status::kOK);
     assert(!r->data().empty());
 
 #if WEBCC_ENABLE_SSL
 
-    r = session.Send(webcc::RequestBuilder{}.
-                     Get("https://httpbin.org/get")
-                     ());
+    r = session.Send(WEBCC_GET("https://httpbin.org/get")());
 
     assert(r->status() == webcc::Status::kOK);
     assert(!r->data().empty());

examples/google_client.cc

@@ -0,0 +1,35 @@
+// google_client.cc
+// This example sends a GET request to https://www.google.com/.
+
+// NOTE:
+// - The response body is chunked
+// - The Google server requires the client to call `SSL_set_tlsext_host_name()`
+//   or the SSL handshake would fail. This is different from other HTTPS servers
+//   like api.github.com or httpbin.org.
+
+#include <cassert>
+#include <iostream>
+
+#include "webcc/client_session.h"
+#include "webcc/logger.h"
+
+int main() {
+  WEBCC_LOG_INIT("", webcc::LOG_CONSOLE);
+
+  webcc::ClientSession session;
+
+  try {
+    auto r = session.Send(WEBCC_GET("https://www.google.com/")());
+
+    std::cout << std::endl;
+    std::cout << r->status() << std::endl;
+    std::cout << std::endl;
+    std::cout << r->data() << std::endl;
+
+  } catch (const webcc::Error& error) {
+    std::cerr << error << std::endl;
+    return 1;
+  }
+
+  return 0;
+}

webcc/CMakeLists.txt

@@ -46,7 +46,7 @@ target_link_libraries(${TARGET} ${Boost_LIBRARIES})
 
 # ZLIB
 if(WEBCC_ENABLE_GZIP)
-	# The imported target ZLIB::ZLIB could be used instead.
+    # The imported target ZLIB::ZLIB could be used instead.
     target_link_libraries(${TARGET} ${ZLIB_LIBRARIES})
 endif()
 

webcc/client_session.cc

@@ -74,7 +74,7 @@ static bool UseSystemCertificateStore(SSL_CTX* ssl_ctx) {
 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),
+      ssl_context_(boost::asio::ssl::context::sslv23_client),
 #endif
       buffer_size_(buffer_size) {
 #if WEBCC_ENABLE_SSL

webcc/client_session.h

@@ -111,7 +111,6 @@ private:
   using ExecutorType = boost::asio::io_context::executor_type;
   boost::asio::executor_work_guard<ExecutorType> work_guard_;
 
-  // TODO
 #if WEBCC_ENABLE_SSL
   boost::asio::ssl::context ssl_context_;
 #endif

webcc/parser.cc

@@ -333,9 +333,23 @@ bool Parser::ParseChunkedContent(const char* data, std::size_t length) {
   pending_data_.append(data, length);
 
   while (true) {
+    if (pending_data_.empty()) {
+      // Wait for more data from next read.
+      break;
+    }
+
     // Read chunk-size if necessary.
     if (chunk_size_ == kInvalidLength) {
-      if (!ParseChunkSize()) {
+      std::string line;
+      if (!GetNextLine(0, &line, true)) {
+        // Need more data from next read.
+        // Normally, it shouldn't be here since the chunk size line is very
+        // short.
+        break;
+      }
+
+      if (!ParseChunkSize(line)) {
+        // Invalid chunk size, stop the parsing.
         return false;
       }
 
@@ -350,6 +364,8 @@ bool Parser::ParseChunkedContent(const char* data, std::size_t length) {
     if (chunk_size_ + 2 <= pending_data_.size()) {  // +2 for CRLF
       body_handler_->AddContent(pending_data_.c_str(), chunk_size_);
 
+      // Pending data might become empty after erase. See the empty check at the
+      // beginning of the loop.
       pending_data_.erase(0, chunk_size_ + 2);
 
       // Reset chunk-size (NOT to 0).
@@ -380,18 +396,10 @@ bool Parser::ParseChunkedContent(const char* data, std::size_t length) {
   return true;
 }
 
-bool Parser::ParseChunkSize() {
-  LOG_VERB("Parse chunk size");
-
-  std::string line;
-  if (!GetNextLine(0, &line, true)) {
-    return true;
-  }
-
+bool Parser::ParseChunkSize(const std::string& line) {
   LOG_VERB("Chunk size line: [%s]", line.c_str());
 
   std::string hex_str;  // e.g., "cf0" (3312)
-
   std::size_t pos = line.find(' ');
   if (pos != std::string::npos) {
     hex_str = line.substr(0, pos);

webcc/parser.h

@@ -121,6 +121,8 @@ public:
     return content_length_;
   }
 
+  // Parse the given length of data.
+  // Return false if the parsing is failed.
   bool Parse(const char* data, std::size_t length);
 
 protected:
@@ -152,7 +154,8 @@ protected:
   bool ParseFixedContent(const char* data, std::size_t length);
 
   bool ParseChunkedContent(const char* data, std::size_t length);
-  bool ParseChunkSize();
+
+  bool ParseChunkSize(const std::string& line);
 
   bool IsFixedContentFull() const;
 

webcc/server.cc

@@ -16,7 +16,7 @@ using tcp = boost::asio::ip::tcp;
 namespace webcc {
 
 // NOTE:
-// Using `asio::strand` is possible but not neccessary:
+// Using `asio::strand` is possible but not necessary:
 //   Define a memeber variable:
 //     asio::strand<asio::io_context::executor_type> strand_;
 //   Initialize the strand with io_context:

webcc/socket.cc

@@ -2,6 +2,7 @@
 
 #include "boost/asio/connect.hpp"
 #include "boost/asio/read.hpp"
+#include "boost/asio/ssl.hpp"
 #include "boost/asio/write.hpp"
 
 #include "webcc/logger.h"
@@ -69,6 +70,14 @@ void SslSocket::AsyncConnect(const std::string& host,
                              ConnectHandler&& handler) {
   connect_handler_ = std::move(handler);
 
+  // Set SNI (server name indication) host name.
+  // Many hosts need this to handshake successfully (e.g., google.com).
+  // Inspired by Boost.Beast.
+  if (!SSL_set_tlsext_host_name(ssl_stream_.native_handle(), host.c_str())) {
+    // TODO: Call ERR_get_error() to get error.
+    LOG_ERRO("Failed to set SNI host name for SSL");
+  }
+
   // Modes `ssl::verify_fail_if_no_peer_cert` and `ssl::verify_client_once` are
   // for server only. `ssl::verify_none` is not secure.
   // See: https://stackoverflow.com/a/12621528
@@ -97,6 +106,25 @@ void SslSocket::AsyncReadSome(ReadHandler&& handler,
 
 bool SslSocket::Shutdown() {
   boost::system::error_code ec;
+
+  ssl_stream_.lowest_layer().cancel(ec);
+
+  // Shutdown SSL
+  // TODO: Use async_shutdown()?
+  ssl_stream_.shutdown(ec);
+
+  if (ec == boost::asio::error::eof) {
+    // See: https://stackoverflow.com/a/25703699
+    ec = {};
+  }
+
+  if (ec) {
+    LOG_WARN("SSL shutdown error (%s)", ec.message().c_str());
+    return false;
+  }
+
+  // Shutdown TCP
+  // TODO: Not sure if this is necessary?
   ssl_stream_.lowest_layer().shutdown(tcp::socket::shutdown_both, ec);
 
   if (ec) {