Support raw IRC messages

Messages received on an IRC server JID are forwarded as raw IRC messages.

fix #2486

doc/biboumi.1.md

@@ -357,6 +357,20 @@ Biboumi supports a few ad-hoc commands, as described in the XEP 0050.
     “Gateway shutdown” quit message, except that biboumi does not exit when
     using this ad-hoc command.
 
+### Raw IRC messages
+
+Biboumi tries to support as many IRC features as possible, but doesn’t
+handle everything yet (or ever).  In order to let the user send any
+arbitrary IRC message, biboumi forwards any XMPP message received on an IRC
+Server JID (see *ADDRESSING*) as a raw command to that IRC server.
+
+For example, to WHOIS the user Foo on the server irc.example.com, a user can
+send the message “WHOIS Foo” to “irc.example.com@biboumi.example.com”.
+
+The message will be forwarded as is, without any modification appart from
+adding "\r\n" at the end (to make it a valid IRC message).  You need to have
+a little bit of understanding of the IRC protocol to use this feature.
+
 SECURITY
 --------
 

src/bridge/bridge.cpp

@@ -273,6 +273,17 @@ void Bridge::send_private_message(const Iid& iid, const std::string& body, const
     }
 }
 
+void Bridge::send_raw_message(const std::string& hostname, const std::string& body)
+{
+  IrcClient* irc = this->get_irc_client(hostname);
+  if (!irc)
+    {
+      log_warning("Cannot send message: no client exist for server " << hostname);
+      return ;
+    }
+  irc->send_raw(body);
+}
+
 void Bridge::leave_irc_channel(Iid&& iid, std::string&& status_message)
 {
   IrcClient* irc = this->get_irc_client(iid.get_server());

src/bridge/bridge.hpp

@@ -61,6 +61,7 @@ public:
   bool join_irc_channel(const Iid& iid, const std::string& username, const std::string& password);
   void send_channel_message(const Iid& iid, const std::string& body);
   void send_private_message(const Iid& iid, const std::string& body, const std::string& type="PRIVMSG");
+  void send_raw_message(const std::string& hostname, const std::string& body);
   void leave_irc_channel(Iid&& iid, std::string&& status_message);
   void send_irc_nick_change(const Iid& iid, const std::string& new_nick);
   void send_irc_kick(const Iid& iid, const std::string& target, const std::string& reason,

src/irc/irc_client.cpp

@@ -181,6 +181,11 @@ void IrcClient::send_message(IrcMessage&& message)
   this->send_data(std::move(res));
 }
 
+void IrcClient::send_raw(const std::string& txt)
+{
+  this->send_data(txt + "\r\n");
+}
+
 void IrcClient::send_user_command(const std::string& username, const std::string& realname)
 {
   this->send_message(IrcMessage("USER", {username, "ignored", "ignored", realname}));

src/irc/irc_client.hpp

@@ -66,6 +66,7 @@ public:
    * for send events to be ready)
    */
   void send_message(IrcMessage&& message);
+  void send_raw(const std::string& txt);
   /**
    * Send the PONG irc command
    */

src/xmpp/biboumi_component.cpp

@@ -211,6 +211,11 @@ void BiboumiComponent::handle_message(const Stanza& stanza)
               bridge->send_private_message(user_iid, body->get_inner());
               bridge->set_preferred_from_jid(user_iid.get_local(), to_str);
             }
+          else if (!iid.is_user && !iid.is_channel)
+            { // Message sent to the server JID
+              // Convert the message body into a raw IRC message
+              bridge->send_raw_message(iid.get_server(), body->get_inner());
+            }
         }
     }
   else if (iid.is_user)