Check the number of argument of every IRC command received from the server

Each IrcClient callback has a max and min size of argument, we call the
callback only if the parsed message has a correct number of arguments,
otherwise it is ignored (with a warning logged).

2 files changed, 103 insertions, 90 deletions

diff --git a/src/irc/irc_client.cpp b/src/irc/irc_client.cpp
index 4e8385c..6ab19b7 100644
--- a/src/irc/irc_client.cpp
+++ b/src/irc/irc_client.cpp
@@ -150,14 +150,26 @@ void IrcClient::parse_in_buffer(const size_t)
 
       // Call the standard callback (if any), associated with the command
       // name that we just received.
-      auto cb = irc_callbacks.find(message.command);
-      if (cb != irc_callbacks.end())
+      auto it = irc_callbacks.find(message.command);
+      if (it != irc_callbacks.end())
         {
-          try {
-            (this->*(cb->second))(message);
-          } catch (const std::exception& e) {
-            log_error("Unhandled exception: " << e.what());
-          }
+          const auto& limits = it->second.second;
+          // Check that the Message is well formed before actually calling
+          // the callback. limits.first is the min number of arguments,
+          // second is the max
+          if (message.arguments.size() < limits.first ||
+              (limits.second > 0 && message.arguments.size() > limits.second))
+            log_warning("Invalid number of arguments for IRC command “" << message.command <<
+                        "”: " << message.arguments.size());
+          else
+            {
+              const auto& cb = it->second.first;
+              try {
+                (this->*(cb))(message);
+              } catch (const std::exception& e) {
+                log_error("Unhandled exception: " << e.what());
+              }
+            }
         }
       else
         {
diff --git a/src/irc/irc_client.hpp b/src/irc/irc_client.hpp
index 0d1604d..a3f69a0 100644
--- a/src/irc/irc_client.hpp
+++ b/src/irc/irc_client.hpp
@@ -336,90 +336,91 @@ private:
  */
 typedef void (IrcClient::*irc_callback_t)(const IrcMessage&);
 
-static const std::unordered_map<std::string, irc_callback_t> irc_callbacks = {
-  {"NOTICE", &IrcClient::on_notice},
-  {"002", &IrcClient::forward_server_message},
-  {"003", &IrcClient::forward_server_message},
-  {"005", &IrcClient::on_isupport_message},
-  {"RPL_LISTSTART", &IrcClient::on_rpl_liststart},
-  {"321", &IrcClient::on_rpl_liststart},
-  {"RPL_LIST", &IrcClient::on_rpl_list},
-  {"322", &IrcClient::on_rpl_list},
-  {"RPL_LISTEND", &IrcClient::on_rpl_listend},
-  {"323", &IrcClient::on_rpl_listend},
-  {"RPL_MOTDSTART", &IrcClient::empty_motd},
-  {"375", &IrcClient::empty_motd},
-  {"RPL_MOTD", &IrcClient::on_motd_line},
-  {"372", &IrcClient::on_motd_line},
-  {"RPL_MOTDEND", &IrcClient::send_motd},
-  {"376", &IrcClient::send_motd},
-  {"JOIN", &IrcClient::on_channel_join},
-  {"PRIVMSG", &IrcClient::on_channel_message},
-  {"353", &IrcClient::set_and_forward_user_list},
-  {"332", &IrcClient::on_topic_received},
-  {"TOPIC", &IrcClient::on_topic_received},
-  {"366", &IrcClient::on_channel_completely_joined},
-  {"432", &IrcClient::on_erroneous_nickname},
-  {"433", &IrcClient::on_nickname_conflict},
-  {"438", &IrcClient::on_nickname_change_too_fast},
-  {"001", &IrcClient::on_welcome_message},
-  {"PART", &IrcClient::on_part},
-  {"ERROR", &IrcClient::on_error},
-  {"QUIT", &IrcClient::on_quit},
-  {"NICK", &IrcClient::on_nick},
-  {"MODE", &IrcClient::on_mode},
-  {"PING", &IrcClient::send_pong_command},
-  {"PONG", &IrcClient::on_pong},
-  {"KICK", &IrcClient::on_kick},
+static const std::unordered_map<std::string,
+                                std::pair<irc_callback_t, std::pair<std::size_t, std::size_t>>> irc_callbacks = {
+  {"NOTICE", {&IrcClient::on_notice, {2, 0}}},
+  {"002", {&IrcClient::forward_server_message, {2, 0}}},
+  {"003", {&IrcClient::forward_server_message, {2, 0}}},
+  {"005", {&IrcClient::on_isupport_message, {0, 0}}},
+  {"RPL_LISTSTART", {&IrcClient::on_rpl_liststart, {0, 0}}},
+  {"321", {&IrcClient::on_rpl_liststart, {0, 0}}},
+  {"RPL_LIST", {&IrcClient::on_rpl_list, {0, 0}}},
+  {"322", {&IrcClient::on_rpl_list, {0, 0}}},
+  {"RPL_LISTEND", {&IrcClient::on_rpl_listend, {0, 0}}},
+  {"323", {&IrcClient::on_rpl_listend, {0, 0}}},
+  {"RPL_MOTDSTART", {&IrcClient::empty_motd, {0, 0}}},
+  {"375", {&IrcClient::empty_motd, {0, 0}}},
+  {"RPL_MOTD", {&IrcClient::on_motd_line, {2, 0}}},
+  {"372", {&IrcClient::on_motd_line, {2, 0}}},
+  {"RPL_MOTDEND", {&IrcClient::send_motd, {0, 0}}},
+  {"376", {&IrcClient::send_motd, {0, 0}}},
+  {"JOIN", {&IrcClient::on_channel_join, {1, 0}}},
+  {"PRIVMSG", {&IrcClient::on_channel_message, {2, 0}}},
+  {"353", {&IrcClient::set_and_forward_user_list, {4, 0}}},
+  {"332", {&IrcClient::on_topic_received, {2, 0}}},
+  {"TOPIC", {&IrcClient::on_topic_received, {2, 0}}},
+  {"366", {&IrcClient::on_channel_completely_joined, {2, 0}}},
+  {"432", {&IrcClient::on_erroneous_nickname, {2, 0}}},
+  {"433", {&IrcClient::on_nickname_conflict, {2, 0}}},
+  {"438", {&IrcClient::on_nickname_change_too_fast, {2, 0}}},
+  {"001", {&IrcClient::on_welcome_message, {1, 0}}},
+  {"PART", {&IrcClient::on_part, {1, 0}}},
+  {"ERROR", {&IrcClient::on_error, {1, 0}}},
+  {"QUIT", {&IrcClient::on_quit, {0, 0}}},
+  {"NICK", {&IrcClient::on_nick, {1, 0}}},
+  {"MODE", {&IrcClient::on_mode, {1, 0}}},
+  {"PING", {&IrcClient::send_pong_command, {1, 0}}},
+  {"PONG", {&IrcClient::on_pong, {0, 0}}},
+  {"KICK", {&IrcClient::on_kick, {3, 0}}},
 
-  {"401", &IrcClient::on_generic_error},
-  {"402", &IrcClient::on_generic_error},
-  {"403", &IrcClient::on_generic_error},
-  {"404", &IrcClient::on_generic_error},
-  {"405", &IrcClient::on_generic_error},
-  {"406", &IrcClient::on_generic_error},
-  {"407", &IrcClient::on_generic_error},
-  {"408", &IrcClient::on_generic_error},
-  {"409", &IrcClient::on_generic_error},
-  {"410", &IrcClient::on_generic_error},
-  {"411", &IrcClient::on_generic_error},
-  {"412", &IrcClient::on_generic_error},
-  {"414", &IrcClient::on_generic_error},
-  {"421", &IrcClient::on_generic_error},
-  {"422", &IrcClient::on_generic_error},
-  {"423", &IrcClient::on_generic_error},
-  {"424", &IrcClient::on_generic_error},
-  {"431", &IrcClient::on_generic_error},
-  {"436", &IrcClient::on_generic_error},
-  {"441", &IrcClient::on_generic_error},
-  {"442", &IrcClient::on_generic_error},
-  {"443", &IrcClient::on_generic_error},
-  {"444", &IrcClient::on_generic_error},
-  {"446", &IrcClient::on_generic_error},
-  {"451", &IrcClient::on_generic_error},
-  {"461", &IrcClient::on_generic_error},
-  {"462", &IrcClient::on_generic_error},
-  {"463", &IrcClient::on_generic_error},
-  {"464", &IrcClient::on_generic_error},
-  {"465", &IrcClient::on_generic_error},
-  {"467", &IrcClient::on_generic_error},
-  {"470", &IrcClient::on_generic_error},
-  {"471", &IrcClient::on_generic_error},
-  {"472", &IrcClient::on_generic_error},
-  {"473", &IrcClient::on_generic_error},
-  {"474", &IrcClient::on_generic_error},
-  {"475", &IrcClient::on_generic_error},
-  {"476", &IrcClient::on_generic_error},
-  {"477", &IrcClient::on_generic_error},
-  {"481", &IrcClient::on_generic_error},
-  {"482", &IrcClient::on_generic_error},
-  {"483", &IrcClient::on_generic_error},
-  {"484", &IrcClient::on_generic_error},
-  {"485", &IrcClient::on_generic_error},
-  {"487", &IrcClient::on_generic_error},
-  {"491", &IrcClient::on_generic_error},
-  {"501", &IrcClient::on_generic_error},
-  {"502", &IrcClient::on_generic_error},
+  {"401", {&IrcClient::on_generic_error, {2, 0}}},
+  {"402", {&IrcClient::on_generic_error, {2, 0}}},
+  {"403", {&IrcClient::on_generic_error, {2, 0}}},
+  {"404", {&IrcClient::on_generic_error, {2, 0}}},
+  {"405", {&IrcClient::on_generic_error, {2, 0}}},
+  {"406", {&IrcClient::on_generic_error, {2, 0}}},
+  {"407", {&IrcClient::on_generic_error, {2, 0}}},
+  {"408", {&IrcClient::on_generic_error, {2, 0}}},
+  {"409", {&IrcClient::on_generic_error, {2, 0}}},
+  {"410", {&IrcClient::on_generic_error, {2, 0}}},
+  {"411", {&IrcClient::on_generic_error, {2, 0}}},
+  {"412", {&IrcClient::on_generic_error, {2, 0}}},
+  {"414", {&IrcClient::on_generic_error, {2, 0}}},
+  {"421", {&IrcClient::on_generic_error, {2, 0}}},
+  {"422", {&IrcClient::on_generic_error, {2, 0}}},
+  {"423", {&IrcClient::on_generic_error, {2, 0}}},
+  {"424", {&IrcClient::on_generic_error, {2, 0}}},
+  {"431", {&IrcClient::on_generic_error, {2, 0}}},
+  {"436", {&IrcClient::on_generic_error, {2, 0}}},
+  {"441", {&IrcClient::on_generic_error, {2, 0}}},
+  {"442", {&IrcClient::on_generic_error, {2, 0}}},
+  {"443", {&IrcClient::on_generic_error, {2, 0}}},
+  {"444", {&IrcClient::on_generic_error, {2, 0}}},
+  {"446", {&IrcClient::on_generic_error, {2, 0}}},
+  {"451", {&IrcClient::on_generic_error, {2, 0}}},
+  {"461", {&IrcClient::on_generic_error, {2, 0}}},
+  {"462", {&IrcClient::on_generic_error, {2, 0}}},
+  {"463", {&IrcClient::on_generic_error, {2, 0}}},
+  {"464", {&IrcClient::on_generic_error, {2, 0}}},
+  {"465", {&IrcClient::on_generic_error, {2, 0}}},
+  {"467", {&IrcClient::on_generic_error, {2, 0}}},
+  {"470", {&IrcClient::on_generic_error, {2, 0}}},
+  {"471", {&IrcClient::on_generic_error, {2, 0}}},
+  {"472", {&IrcClient::on_generic_error, {2, 0}}},
+  {"473", {&IrcClient::on_generic_error, {2, 0}}},
+  {"474", {&IrcClient::on_generic_error, {2, 0}}},
+  {"475", {&IrcClient::on_generic_error, {2, 0}}},
+  {"476", {&IrcClient::on_generic_error, {2, 0}}},
+  {"477", {&IrcClient::on_generic_error, {2, 0}}},
+  {"481", {&IrcClient::on_generic_error, {2, 0}}},
+  {"482", {&IrcClient::on_generic_error, {2, 0}}},
+  {"483", {&IrcClient::on_generic_error, {2, 0}}},
+  {"484", {&IrcClient::on_generic_error, {2, 0}}},
+  {"485", {&IrcClient::on_generic_error, {2, 0}}},
+  {"487", {&IrcClient::on_generic_error, {2, 0}}},
+  {"491", {&IrcClient::on_generic_error, {2, 0}}},
+  {"501", {&IrcClient::on_generic_error, {2, 0}}},
+  {"502", {&IrcClient::on_generic_error, {2, 0}}},
 };
 
 #endif // IRC_CLIENT_INCLUDED