Updated version 3.0 from 'upstream/3.0'

with Debian dir 0f18938e98f5a466f36719f60cef0490163ab845

1 files changed, 501 insertions, 0 deletions

diff --git a/louloulibs/network/tcp_socket_handler.cpp b/louloulibs/network/tcp_socket_handler.cpp
new file mode 100644
index 0000000..5420b1c
--- /dev/null
+++ b/louloulibs/network/tcp_socket_handler.cpp
@@ -0,0 +1,501 @@
+#include <network/tcp_socket_handler.hpp>
+#include <network/dns_handler.hpp>
+
+#include <utils/timed_events.hpp>
+#include <utils/scopeguard.hpp>
+#include <network/poller.hpp>
+
+#include <logger/logger.hpp>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <stdexcept>
+#include <unistd.h>
+#include <errno.h>
+#include <cstring>
+#include <fcntl.h>
+
+#ifdef BOTAN_FOUND
+# include <botan/hex.h>
+# include <botan/tls_exceptn.h>
+
+Botan::AutoSeeded_RNG TCPSocketHandler::rng;
+Botan::TLS::Policy TCPSocketHandler::policy;
+Botan::TLS::Session_Manager_In_Memory TCPSocketHandler::session_manager(TCPSocketHandler::rng);
+
+#endif
+
+#ifndef UIO_FASTIOV
+# define UIO_FASTIOV 8
+#endif
+
+using namespace std::string_literals;
+using namespace std::chrono_literals;
+
+namespace ph = std::placeholders;
+
+TCPSocketHandler::TCPSocketHandler(std::shared_ptr<Poller> poller):
+  SocketHandler(poller, -1),
+  use_tls(false),
+  connected(false),
+  connecting(false),
+  hostname_resolution_failed(false)
+#ifdef BOTAN_FOUND
+  ,credential_manager(this)
+#endif
+{}
+
+TCPSocketHandler::~TCPSocketHandler()
+{
+  this->close();
+}
+
+
+void TCPSocketHandler::init_socket(const struct addrinfo* rp)
+{
+  if (this->socket != -1)
+    ::close(this->socket);
+  if ((this->socket = ::socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol)) == -1)
+    throw std::runtime_error("Could not create socket: "s + strerror(errno));
+  // Bind the socket to a specific address, if specified
+  if (!this->bind_addr.empty())
+    {
+      // Convert the address from string format to a sockaddr that can be
+      // used in bind()
+      struct addrinfo* result;
+      int err = ::getaddrinfo(this->bind_addr.data(), nullptr, nullptr, &result);
+      if (err != 0 || !result)
+        log_error("Failed to bind socket to ", this->bind_addr, ": ",
+                  gai_strerror(err));
+      else
+        {
+          utils::ScopeGuard sg([result](){ freeaddrinfo(result); });
+          struct addrinfo* rp;
+          int bind_error = 0;
+          for (rp = result; rp; rp = rp->ai_next)
+            {
+              if ((bind_error = ::bind(this->socket,
+                         reinterpret_cast<const struct sockaddr*>(rp->ai_addr),
+                         rp->ai_addrlen)) == 0)
+                break;
+            }
+          if (!rp)
+            log_error("Failed to bind socket to ", this->bind_addr, ": ",
+                      strerror(bind_error));
+          else
+            log_info("Socket successfully bound to ", this->bind_addr);
+        }
+    }
+  int optval = 1;
+  if (::setsockopt(this->socket, SOL_SOCKET, SO_KEEPALIVE, &optval, sizeof(optval)) == -1)
+    log_warning("Failed to enable TCP keepalive on socket: ", strerror(errno));
+  // Set the socket on non-blocking mode.  This is useful to receive a EAGAIN
+  // error when connect() would block, to not block the whole process if a
+  // remote is not responsive.
+  const int existing_flags = ::fcntl(this->socket, F_GETFL, 0);
+  if ((existing_flags == -1) ||
+      (::fcntl(this->socket, F_SETFL, existing_flags | O_NONBLOCK) == -1))
+    throw std::runtime_error("Could not initialize socket: "s + strerror(errno));
+}
+
+void TCPSocketHandler::connect(const std::string& address, const std::string& port, const bool tls)
+{
+  this->address = address;
+  this->port = port;
+  this->use_tls = tls;
+
+  utils::ScopeGuard sg;
+
+  struct addrinfo* addr_res;
+
+  if (!this->connecting)
+    {
+      // Get the addrinfo from getaddrinfo (or ares_gethostbyname), only if
+      // this is the first call of this function.
+      if (!this->resolver.is_resolved())
+        {
+          log_info("Trying to connect to ", address, ":", port);
+          // Start the asynchronous process of resolving the hostname. Once
+          // the addresses have been found and `resolved` has been set to true
+          // (but connecting will still be false), TCPSocketHandler::connect()
+          // needs to be called, again.
+          this->resolver.resolve(address, port,
+                                 [this](const struct addrinfo*)
+                                 {
+                                   log_debug("Resolution success, calling connect() again");
+                                   this->connect();
+                                 },
+                                 [this](const char*)
+                                 {
+                                   log_debug("Resolution failed, calling connect() again");
+                                   this->connect();
+                                 });
+          return;
+        }
+      else
+        {
+          // The c-ares resolved the hostname and the available addresses
+          // where saved in the cares_addrinfo linked list. Now, just use
+          // this list to try to connect.
+          addr_res = this->resolver.get_result().get();
+          if (!addr_res)
+            {
+              this->hostname_resolution_failed = true;
+              const auto msg = this->resolver.get_error_message();
+              this->close();
+              this->on_connection_failed(msg);
+              return ;
+            }
+        }
+    }
+  else
+    { // This function is called again, use the saved addrinfo structure,
+      // instead of re-doing the whole getaddrinfo process.
+      addr_res = &this->addrinfo;
+    }
+
+  for (struct addrinfo* rp = addr_res; rp; rp = rp->ai_next)
+    {
+      if (!this->connecting)
+        {
+          try {
+            this->init_socket(rp);
+          }
+          catch (const std::runtime_error& error) {
+            log_error("Failed to init socket: ", error.what());
+            break;
+          }
+        }
+
+      this->display_resolved_ip(rp);
+
+      if (::connect(this->socket, rp->ai_addr, rp->ai_addrlen) == 0
+          || errno == EISCONN)
+        {
+          log_info("Connection success.");
+          TimedEventsManager::instance().cancel("connection_timeout"s +
+                                                std::to_string(this->socket));
+          this->poller->add_socket_handler(this);
+          this->connected = true;
+          this->connecting = false;
+#ifdef BOTAN_FOUND
+          if (this->use_tls)
+            this->start_tls();
+#endif
+          this->on_connected();
+          return ;
+        }
+      else if (errno == EINPROGRESS || errno == EALREADY)
+        {   // retry this process later, when the socket
+            // is ready to be written on.
+          this->connecting = true;
+          this->poller->add_socket_handler(this);
+          this->poller->watch_send_events(this);
+          // Save the addrinfo structure, to use it on the next call
+          this->ai_addrlen = rp->ai_addrlen;
+          memcpy(&this->ai_addr, rp->ai_addr, this->ai_addrlen);
+          memcpy(&this->addrinfo, rp, sizeof(struct addrinfo));
+          this->addrinfo.ai_addr = reinterpret_cast<struct sockaddr*>(&this->ai_addr);
+          this->addrinfo.ai_next = nullptr;
+          // If the connection has not succeeded or failed in 5s, we consider
+          // it to have failed
+          TimedEventsManager::instance().add_event(
+                                                   TimedEvent(std::chrono::steady_clock::now() + 5s,
+                                                              std::bind(&TCPSocketHandler::on_connection_timeout, this),
+                                                              "connection_timeout"s + std::to_string(this->socket)));
+          return ;
+        }
+      log_info("Connection failed:", strerror(errno));
+    }
+  log_error("All connection attempts failed.");
+  this->close();
+  this->on_connection_failed(strerror(errno));
+  return ;
+}
+
+void TCPSocketHandler::on_connection_timeout()
+{
+  this->close();
+  this->on_connection_failed("connection timed out");
+}
+
+void TCPSocketHandler::connect()
+{
+  this->connect(this->address, this->port, this->use_tls);
+}
+
+void TCPSocketHandler::on_recv()
+{
+#ifdef BOTAN_FOUND
+  if (this->use_tls)
+    this->tls_recv();
+  else
+#endif
+    this->plain_recv();
+}
+
+void TCPSocketHandler::plain_recv()
+{
+  static constexpr size_t buf_size = 4096;
+  char buf[buf_size];
+  void* recv_buf = this->get_receive_buffer(buf_size);
+
+  if (recv_buf == nullptr)
+    recv_buf = buf;
+
+  const ssize_t size = this->do_recv(recv_buf, buf_size);
+
+  if (size > 0)
+    {
+      if (buf == recv_buf)
+        {
+          // data needs to be placed in the in_buf string, because no buffer
+          // was provided to receive that data directly. The in_buf buffer
+          // will be handled in parse_in_buffer()
+          this->in_buf += std::string(buf, size);
+        }
+      this->parse_in_buffer(size);
+    }
+}
+
+ssize_t TCPSocketHandler::do_recv(void* recv_buf, const size_t buf_size)
+{
+  ssize_t size = ::recv(this->socket, recv_buf, buf_size, 0);
+  if (0 == size)
+    {
+      this->on_connection_close("");
+      this->close();
+    }
+  else if (-1 == size)
+    {
+      if (this->connecting)
+        log_warning("Error connecting: ", strerror(errno));
+      else
+        log_warning("Error while reading from socket: ", strerror(errno));
+      // Remember if we were connecting, or already connected when this
+      // happened, because close() sets this->connecting to false
+      const auto were_connecting = this->connecting;
+      this->close();
+      if (were_connecting)
+        this->on_connection_failed(strerror(errno));
+      else
+        this->on_connection_close(strerror(errno));
+    }
+  return size;
+}
+
+void TCPSocketHandler::on_send()
+{
+  struct iovec msg_iov[UIO_FASTIOV] = {};
+  struct msghdr msg{nullptr, 0,
+      msg_iov,
+      0, nullptr, 0, 0};
+  for (const std::string& s: this->out_buf)
+    {
+      // unconsting the content of s is ok, sendmsg will never modify it
+      msg_iov[msg.msg_iovlen].iov_base = const_cast<char*>(s.data());
+      msg_iov[msg.msg_iovlen].iov_len = s.size();
+      if (++msg.msg_iovlen == UIO_FASTIOV)
+        break;
+    }
+  ssize_t res = ::sendmsg(this->socket, &msg, MSG_NOSIGNAL);
+  if (res < 0)
+    {
+      log_error("sendmsg failed: ", strerror(errno));
+      this->on_connection_close(strerror(errno));
+      this->close();
+    }
+  else
+    {
+      // remove all the strings that were successfully sent.
+      for (auto it = this->out_buf.begin();
+           it != this->out_buf.end();)
+        {
+          if (static_cast<size_t>(res) >= (*it).size())
+            {
+              res -= (*it).size();
+              it = this->out_buf.erase(it);
+            }
+          else
+            {
+              // If one string has partially been sent, we use substr to
+              // crop it
+              if (res > 0)
+                (*it) = (*it).substr(res, std::string::npos);
+              break;
+            }
+        }
+      if (this->out_buf.empty())
+        this->poller->stop_watching_send_events(this);
+    }
+}
+
+void TCPSocketHandler::close()
+{
+  TimedEventsManager::instance().cancel("connection_timeout"s +
+                                        std::to_string(this->socket));
+  if (this->connected || this->connecting)
+    this->poller->remove_socket_handler(this->get_socket());
+  if (this->socket != -1)
+    {
+      ::close(this->socket);
+      this->socket = -1;
+    }
+  this->connected = false;
+  this->connecting = false;
+  this->in_buf.clear();
+  this->out_buf.clear();
+  this->port.clear();
+  this->resolver.clear();
+}
+
+void TCPSocketHandler::display_resolved_ip(struct addrinfo* rp) const
+{
+  if (rp->ai_family == AF_INET)
+    log_debug("Trying IPv4 address ", addr_to_string(rp));
+  else if (rp->ai_family == AF_INET6)
+    log_debug("Trying IPv6 address ", addr_to_string(rp));
+}
+
+void TCPSocketHandler::send_data(std::string&& data)
+{
+#ifdef BOTAN_FOUND
+  if (this->use_tls)
+    try {
+      this->tls_send(std::move(data));
+    } catch (const Botan::TLS::TLS_Exception& e) {
+      this->on_connection_close("TLS error: "s + e.what());
+      this->close();
+      return ;
+    }
+  else
+#endif
+    this->raw_send(std::move(data));
+}
+
+void TCPSocketHandler::raw_send(std::string&& data)
+{
+  if (data.empty())
+    return ;
+  this->out_buf.emplace_back(std::move(data));
+  if (this->connected)
+    this->poller->watch_send_events(this);
+}
+
+void TCPSocketHandler::send_pending_data()
+{
+  if (this->connected && !this->out_buf.empty())
+    this->poller->watch_send_events(this);
+}
+
+bool TCPSocketHandler::is_connected() const
+{
+  return this->connected;
+}
+
+bool TCPSocketHandler::is_connecting() const
+{
+  return this->connecting || this->resolver.is_resolving();
+}
+
+void* TCPSocketHandler::get_receive_buffer(const size_t) const
+{
+  return nullptr;
+}
+
+#ifdef BOTAN_FOUND
+void TCPSocketHandler::start_tls()
+{
+  Botan::TLS::Server_Information server_info(this->address, "irc", std::stoul(this->port));
+  this->tls = std::make_unique<Botan::TLS::Client>(
+      std::bind(&TCPSocketHandler::tls_output_fn, this, ph::_1, ph::_2),
+      std::bind(&TCPSocketHandler::tls_data_cb, this, ph::_1, ph::_2),
+      std::bind(&TCPSocketHandler::tls_alert_cb, this, ph::_1, ph::_2, ph::_3),
+      std::bind(&TCPSocketHandler::tls_handshake_cb, this, ph::_1),
+      session_manager, this->credential_manager, policy,
+      rng, server_info, Botan::TLS::Protocol_Version::latest_tls_version());
+}
+
+void TCPSocketHandler::tls_recv()
+{
+  static constexpr size_t buf_size = 4096;
+  char recv_buf[buf_size];
+
+  const ssize_t size = this->do_recv(recv_buf, buf_size);
+  if (size > 0)
+    {
+      const bool was_active = this->tls->is_active();
+      try {
+        this->tls->received_data(reinterpret_cast<const Botan::byte*>(recv_buf),
+                                 static_cast<size_t>(size));
+      } catch (const Botan::TLS::TLS_Exception& e) {
+        // May happen if the server sends malformed TLS data (buggy server,
+        // or more probably we are just connected to a server that sends
+        // plain-text)
+        this->on_connection_close("TLS error: "s + e.what());
+        this->close();
+        return ;
+      }
+      if (!was_active && this->tls->is_active())
+        this->on_tls_activated();
+    }
+}
+
+void TCPSocketHandler::tls_send(std::string&& data)
+{
+  // We may not be connected yet, or the tls session has
+  // not yet been negociated
+  if (this->tls && this->tls->is_active())
+    {
+      const bool was_active = this->tls->is_active();
+      if (!this->pre_buf.empty())
+        {
+          this->tls->send(reinterpret_cast<const Botan::byte*>(this->pre_buf.data()),
+                          this->pre_buf.size());
+          this->pre_buf = "";
+        }
+      if (!data.empty())
+        this->tls->send(reinterpret_cast<const Botan::byte*>(data.data()),
+                       data.size());
+      if (!was_active && this->tls->is_active())
+        this->on_tls_activated();
+    }
+  else
+    this->pre_buf += data;
+}
+
+void TCPSocketHandler::tls_data_cb(const Botan::byte* data, size_t size)
+{
+  this->in_buf += std::string(reinterpret_cast<const char*>(data),
+                              size);
+  if (!this->in_buf.empty())
+    this->parse_in_buffer(size);
+}
+
+void TCPSocketHandler::tls_output_fn(const Botan::byte* data, size_t size)
+{
+  this->raw_send(std::string(reinterpret_cast<const char*>(data), size));
+}
+
+void TCPSocketHandler::tls_alert_cb(Botan::TLS::Alert alert, const Botan::byte*, size_t)
+{
+  log_debug("tls_alert: ", alert.type_string());
+}
+
+bool TCPSocketHandler::tls_handshake_cb(const Botan::TLS::Session& session)
+{
+  log_debug("Handshake with ", session.server_info().hostname(), " complete.",
+            " Version: ", session.version().to_string(),
+            " using ", session.ciphersuite().to_string());
+  if (!session.session_id().empty())
+    log_debug("Session ID ", Botan::hex_encode(session.session_id()));
+  if (!session.session_ticket().empty())
+    log_debug("Session ticket ", Botan::hex_encode(session.session_ticket()));
+  return true;
+}
+
+void TCPSocketHandler::on_tls_activated()
+{
+  this->send_data({});
+}
+
+#endif // BOTAN_FOUND