Provide a JID for IRC users, and add a stringprep dependency for this

CMakeLists.txt

@@ -20,6 +20,7 @@ find_package(Cryptopp REQUIRED)
 find_package(Iconv REQUIRED)
 include(FindEXPAT)
 find_package(EXPAT REQUIRED)
+find_package(Libidn)
 
 include_directories("src/")
 include_directories(${EXPAT_INCLUDE_DIRS})
@@ -28,6 +29,12 @@ include_directories(${ICONV_INCLUDE_DIRS})
 # coming from these headers.
 include_directories(SYSTEM ${CRYPTO++_INCLUDE_DIRS})
 
+if(LIBIDN_FOUND)
+  include_directories(${LIBIDN_INCLUDE_DIRS})
+else()
+  message("Building without stringprep support.")
+endif()
+
 set(POLLER "POLL" CACHE STRING
   "Choose the poller between POLL and EPOLL (Linux-only)")
 if((NOT ${POLLER} MATCHES "POLL") AND
@@ -35,6 +42,7 @@ if((NOT ${POLLER} MATCHES "POLL") AND
   message(FATAL_ERROR "POLLER must be either POLL or EPOLL")
 endif()
 
+
 #
 ## utils
 #
@@ -83,6 +91,9 @@ file(GLOB source_xmpp
 add_library(xmpp STATIC ${source_xmpp})
 target_link_libraries(xmpp bridge network utils logger
   ${CRYPTO++_LIBRARIES} ${EXPAT_LIBRARIES} pthread)
+if(LIBIDN_FOUND)
+  target_link_libraries(xmpp ${LIBIDN_LIBRARIES})
+endif()
 
 #
 ## bridge

cmake/Modules/FindLibidn.cmake

@@ -0,0 +1,36 @@
+# - Find libidn
+# Find the libidn library, and more particularly the stringprep header.
+#
+# This module defines the following variables:
+#   LIBIDN_FOUND  -  True if library and include directory are found
+# If set to TRUE, the following are also defined:
+#   LIBIDN_INCLUDE_DIRS  -  The directory where to find the header file
+#   LIBIDN_LIBRARIES  -  Where to find the library file
+#
+# For conveniance, these variables are also set. They have the same values
+# than the variables above.  The user can thus choose his/her prefered way
+# to way to write them.
+#   LIBIDN_INCLUDE_DIR
+#   LIBIDN_LIBRARY
+#
+# This file is in the public domain
+
+find_path(LIBIDN_INCLUDE_DIRS NAMES stringprep.h
+  DOC "The libidn include directory")
+
+# The library containing the stringprep module is libidn
+find_library(LIBIDN_LIBRARIES NAMES idn
+  DOC "The libidn library")
+
+# Use some standard module to handle the QUIETLY and REQUIRED arguments, and
+# set LIBIDN_FOUND to TRUE if these two variables are set.
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(Libidn REQUIRED_VARS LIBIDN_LIBRARIES LIBIDN_INCLUDE_DIRS)
+
+# Compatibility for all the ways of writing these variables
+if(LIBIDN_FOUND)
+  set(LIBIDN_INCLUDE_DIR ${LIBIDN_INCLUDE_DIRS})
+  set(LIBIDN_LIBRARY ${LIBIDN_LIBRARIES})
+endif()
+
+mark_as_advanced(LIBIDN_INCLUDE_DIRS LIBIDN_LIBRARIES)

config.h.cmake

@@ -1,2 +1,3 @@
 #cmakedefine ICONV_SECOND_ARGUMENT_IS_CONST
+#cmakedefine LIBIDN_FOUND
 #cmakedefine POLLER ${POLLER}

src/bridge/bridge.cpp

@@ -167,9 +167,11 @@ void Bridge::send_xmpp_message(const std::string& from, const std::string& autho
   this->xmpp->send_message(from, this->make_xmpp_body(body), this->user_jid);
 }
 
-void Bridge::send_user_join(const std::string& hostname, const std::string& chan_name, const std::string nick)
+void Bridge::send_user_join(const std::string& hostname,
+                            const std::string& chan_name,
+                            const IrcUser* user)
 {
-  this->xmpp->send_user_join(chan_name + "%" + hostname, nick, this->user_jid);
+  this->xmpp->send_user_join(chan_name + "%" + hostname, user->nick, user->host, this->user_jid);
 }
 
 void Bridge::send_self_join(const std::string& hostname, const std::string& chan_name, const std::string nick)

src/bridge/bridge.hpp

@@ -3,6 +3,7 @@
 
 #include <irc/irc_client.hpp>
 #include <bridge/colors.hpp>
+#include <irc/irc_user.hpp>
 #include <irc/iid.hpp>
 
 #include <unordered_map>
@@ -56,7 +57,9 @@ public:
   /**
    * Send the presence of a new user in the MUC.
    */
-  void send_user_join(const std::string& hostname, const std::string& chan_name, const std::string nick);
+  void send_user_join(const std::string& hostname,
+                      const std::string& chan_name,
+                      const IrcUser* user);
   /**
    * Send the self presence of an user when the MUC is fully joined.
    */

src/irc/irc_client.cpp

@@ -193,11 +193,11 @@ void IrcClient::set_and_forward_user_list(const IrcMessage& message)
   std::vector<std::string> nicks = utils::split(message.arguments[3], ' ');
   for (const std::string& nick: nicks)
     {
-      IrcUser* user = channel->add_user(nick);
+      const IrcUser* user = channel->add_user(nick);
       if (user->nick != channel->get_self()->nick)
         {
           log_debug("Adding user [" << nick << "] to chan " << chan_name);
-          this->bridge->send_user_join(this->hostname, chan_name, user->nick);
+          this->bridge->send_user_join(this->hostname, chan_name, user);
         }
     }
 }
@@ -214,8 +214,8 @@ void IrcClient::on_channel_join(const IrcMessage& message)
     }
   else
     {
-      IrcUser* user = channel->add_user(nick);
+      const IrcUser* user = channel->add_user(nick);
-      this->bridge->send_user_join(this->hostname, chan_name, user->nick);
+      this->bridge->send_user_join(this->hostname, chan_name, user);
     }
 }
 

src/irc/irc_message.cpp

@@ -9,7 +9,7 @@ IrcMessage::IrcMessage(std::string&& line)
   if (line[0] == ':')
     {
       pos = line.find(" ");
-      this->prefix = line.substr(1, pos);
+      this->prefix = line.substr(1, pos - 1);
       line = line.substr(pos + 1, std::string::npos);
     }
   // command

src/test.cpp

@@ -148,6 +148,11 @@ int main()
   assert(jid2.domain == "ツ.coucou");
   assert(jid2.resource == "coucou@coucou/coucou");
 
+  // Nodeprep
+  const std::string& badjid("~louiz@EpiK-7D9D1FDE.poez.io");
+  const std::string correctjid = jidprep(badjid);
+  assert(correctjid == "~louiz@epik-7d9d1fde.poez.io");
+
   /**
    * Config
    */

src/xmpp/jid.cpp

@@ -1,4 +1,12 @@
 #include <xmpp/jid.hpp>
+#include <config.h>
+#include <cstring>
+
+#ifdef LIBIDN_FOUND
+ #include <stringprep.h>
+#endif
+
+#include <logger/logger.hpp>
 
 Jid::Jid(const std::string& jid)
 {
@@ -19,3 +27,41 @@ Jid::Jid(const std::string& jid)
 
   this->domain = jid.substr(at, slash - at);
 }
+
+#include <iostream>
+
+static constexpr size_t max_jid_part_len = 1023;
+
+std::string jidprep(const std::string& original)
+{
+#ifdef LIBIDN_FOUND
+  // TODO: cache the result
+  const std::string error_msg("Failed to convert " + original + " into a valid JID:");
+  Jid jid(original);
+
+  char local[max_jid_part_len] = {};
+  memcpy(local, jid.local.data(), jid.local.size());
+  Stringprep_rc rc = static_cast<Stringprep_rc>(::stringprep(local, max_jid_part_len,
+                     static_cast<Stringprep_profile_flags>(0), stringprep_xmpp_nodeprep));
+  if (rc != STRINGPREP_OK)
+  {
+    log_error(error_msg + stringprep_strerror(rc));
+    return "";
+  }
+
+  char domain[max_jid_part_len] = {};
+  memcpy(domain, jid.domain.data(), jid.domain.size());
+  rc = static_cast<Stringprep_rc>(::stringprep(domain, max_jid_part_len,
+       static_cast<Stringprep_profile_flags>(0), stringprep_nameprep));
+  if (rc != STRINGPREP_OK)
+  {
+    log_error(error_msg + stringprep_strerror(rc));
+    return "";
+  }
+
+  return std::string(local) + "@" + domain;
+#else
+  (void)original;
+  return "";
+#endif
+}

src/xmpp/jid.hpp

@@ -22,5 +22,15 @@ private:
   Jid& operator=(Jid&&) = delete;
 };
 
+/**
+ * Prepare the given UTF-8 string according to the XMPP node stringprep
+ * identifier profile.  This is used to send properly-formed JID to the XMPP
+ * server.
+ *
+ * If the stringprep library is not found, we return an empty string.  When
+ * this function is used, the result must always be checked for an empty
+ * value, and if this is the case it must not be used as a JID.
+ */
+std::string jidprep(const std::string& original);
 
 #endif // JID_INCLUDED

src/xmpp/xmpp_component.cpp

@@ -267,7 +267,10 @@ void XmppComponent::send_message(const std::string& from, Xmpp::body&& body, con
   this->send_stanza(node);
 }
 
-void XmppComponent::send_user_join(const std::string& from, const std::string& nick, const std::string& to)
+void XmppComponent::send_user_join(const std::string& from,
+                                   const std::string& nick,
+                                   const std::string& realjid,
+                                   const std::string& to)
 {
   XmlNode node("presence");
   node["to"] = to;
@@ -280,6 +283,12 @@ void XmppComponent::send_user_join(const std::string& from, const std::string& n
   XmlNode item("item");
   item["affiliation"] = "member";
   item["role"] = "participant";
+  if (!realjid.empty())
+    {
+      const std::string preped_jid = jidprep(realjid);
+      if (!preped_jid.empty())
+        item["jid"] = preped_jid;
+    }
   item.close();
   x.add_child(std::move(item));
   x.close();
@@ -408,7 +417,7 @@ void XmppComponent::send_nick_change(const std::string& muc_name, const std::str
   if (self)
     this->send_self_join(muc_name, new_nick, jid_to);
   else
-    this->send_user_join(muc_name, new_nick, jid_to);
+    this->send_user_join(muc_name, new_nick, "", jid_to);
 }
 
 void XmppComponent::kick_user(const std::string& muc_name,

src/xmpp/xmpp_component.hpp

@@ -62,7 +62,10 @@ public:
   /**
    * Send a join from a new participant
    */
-  void send_user_join(const std::string& from, const std::string& nick, const std::string& to);
+  void send_user_join(const std::string& from,
+                      const std::string& nick,
+                      const std::string& realjid,
+                      const std::string& to);
   /**
    * Send the self join to the user
    */