Make NOTICE alerts about client (dis)connection and authentication events optional.

New configuration options added:
 - alertconnect
 - alertauthfail
 - alertauthsuccess
 - alertunautheddisconnect
 - alertautheddisconnect

8 files changed, 194 insertions, 37 deletions

diff --git a/README b/README
index 5b217cf..3875fc2 100644
--- a/README
+++ b/README
@@ -37,6 +37,11 @@ These options can be changed by issuing a BLABOUNCER REHASH command or by sendin
  - debug
  - certfile
  - keyfile
+ - alertconnect
+ - alertauthfail
+ - alertauthsuccess
+ - alertunautheddisconnect
+ - alertautheddisconnect
 
 == Commands ==
 
diff --git a/TODO b/TODO
index a4c807b..28fdc13 100644
--- a/TODO
+++ b/TODO
@@ -51,3 +51,11 @@ Are WALLOPS logged & replayed?
 QUIT not logged in all channels a person was in?  (e.g. Joey Mon  1 Apr 20:49:14 BST 2024)
 
 "/whois" with no nick - "No nickname given" goes to all clients - fixable?
+
+Ability to check for updates (and optional at startup?).
+
+Absurd CPU usage and duration doing "/BLABOUNCER REPLAY 24:0" approx. 14/09/2024 17:35.
+
+Send NOTICE about failed authentication before disconnecting.
+
+Failure to read configuration file suggestion that an upgrade may require new settings.
diff --git a/blabouncer.c b/blabouncer.c
index 75ce966..56c21a0 100644
--- a/blabouncer.c
+++ b/blabouncer.c
@@ -888,16 +888,18 @@ void dochat(int *serversockfd, int *clientsockfd, struct settings *settings) {
 
             // TODO - Handle the "find a free element" loop not finding a free element
             debugprint(DEBUG_FULL, "bouncer-client: new connection from %s on socket %d%s\n", remoteip, newfd, opensslfailmsg);
-            // Alert other clients about the new connection
-            char alertmsg[MAXDATASIZE];
-            if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client connected from %s%s.", ircdstate.ircnick,
-                          remoteip, opensslfailmsg)) {
-              fprintf(stderr, "Error while preparing new client connection NOTICE!\n");
-              debugprint(DEBUG_CRIT, "Error while preparing new client connection NOTICE!\n");
-              alertmsg[0] = '\0';
+            // Alert other clients about the new connection (if enabled)
+            if (settings->alertconnect) {
+              char alertmsg[MAXDATASIZE];
+              if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client connected from %s%s.", ircdstate.ircnick,
+                            remoteip, opensslfailmsg)) {
+                fprintf(stderr, "Error while preparing new client connection NOTICE!\n");
+                debugprint(DEBUG_CRIT, "Error while preparing new client connection NOTICE!\n");
+                alertmsg[0] = '\0';
+              }
+              // "except" 0 since we trust this message
+              sendtoallclients(clients, alertmsg, 0, settings);
             }
-            // "except" 0 since we trust this message
-            sendtoallclients(clients, alertmsg, 0, settings);
             debugprint(DEBUG_FULL, "bouncer-client: total client connections: %d\n", numclients(clients));
           }
         // If using client TLS and still pending SSL_accept() then re-try SSL_accept() (it can't be real client data yet)
@@ -1224,6 +1226,41 @@ int main(int argc, char *argv[]) {
     exit(1);
   }
 
+  // Is alerting (NOTICE) upon a new connection enabled?
+  settings.alertconnect = getconfint("alertconnect", settings.conffile);
+  if (errno == ECONFINT) {
+    printf("main(): error getting 'alertconnect' from configuration file.\n");
+    exit(1);
+  }
+
+  // Is alerting (NOTICE) upon a failed authentication enabled?
+  settings.alertauthfail = getconfint("alertauthfail", settings.conffile);
+  if (errno == ECONFINT) {
+    printf("main(): error getting 'alertauthfail' from configuration file.\n");
+    exit(1);
+  }
+
+  // Is alerting (NOTICE) upon a successful authentication enabled?
+  settings.alertauthsuccess = getconfint("alertauthsuccess", settings.conffile);
+  if (errno == ECONFINT) {
+    printf("main(): error getting 'alertauthsuccess' from configuration file.\n");
+    exit(1);
+  }
+
+  // Is alerting (NOTICE) upon unauthenticated client disconnections enabled?
+  settings.alertunautheddisconnect = getconfint("alertunautheddisconnect", settings.conffile);
+  if (errno == ECONFINT) {
+    printf("main(): error getting 'alertunautheddisconnect' from configuration file.\n");
+    exit(1);
+  }
+
+  // Is alerting (NOTICE) upon authenticated client disconnections enabled?
+  settings.alertautheddisconnect = getconfint("alertautheddisconnect", settings.conffile);
+  if (errno == ECONFINT) {
+    printf("main(): error getting 'alertautheddisconnect' from configuration file.\n");
+    exit(1);
+  }
+
   // How many debug logs should we keep?
   settings.debugkeep = getconfint("debugkeep", settings.conffile);
   if (errno == ECONFINT) {
diff --git a/blabouncer.conf.example b/blabouncer.conf.example
index d77689c..2281806 100644
--- a/blabouncer.conf.example
+++ b/blabouncer.conf.example
@@ -108,3 +108,18 @@ debug = "2"
 
 # Number of debug logs to keep
 debugkeep = "5"
+
+# Send NOTICE to all other clients upon new client connections ("1" for yes or "0" for no)
+alertconnect = "1"
+
+# Send NOTICE to all other clients upon clients failing to authenticate ("1" for yes or "0" for no)
+alertauthfail = "1"
+
+# Send NOTICE to all other clients upon clients succesfully authenticating ("1" for yes or "0" for no)
+alertauthsuccess = "1"
+
+# Send NOTICE to all other clients upon unauthenticated client disconnections ("1" for yes or "0" for no)
+alertunautheddisconnect = "1"
+
+# Send NOTICE to all other clients upon authenticated client disconnections ("1" for yes or "0" for no)
+alertautheddisconnect = "1"
diff --git a/config.c b/config.c
index d7ad856..b2868b1 100644
--- a/config.c
+++ b/config.c
@@ -419,7 +419,22 @@ int createconfigfile(char *filename) {
   "debug = \"2\"\n"
   "\n"
   "# Number of debug logs to keep\n"
-  "debugkeep = \"5\"\n";
+  "debugkeep = \"5\"\n"
+  "\n"
+  "# Send NOTICE to all other clients upon new client connections (\"1\" for yes or \"0\" for no)\n"
+  "alertconnect = \"1\"\n"
+  "\n"
+  "# Send NOTICE to all other clients upon clients failing to authenticate (\"1\" for yes or \"0\" for no)\n"
+  "alertauthfail = \"1\"\n"
+  "\n"
+  "# Send NOTICE to all other clients upon clients succesfully authenticating (\"1\" for yes or \"0\" for no)\n"
+  "alertauthsuccess = \"1\"\n"
+  "\n"
+  "# Send NOTICE to all other clients upon unauthenticated client disconnections (\"1\" for yes or \"0\" for no)\n"
+  "alertunautheddisconnect = \"1\"\n"
+  "\n"
+  "# Send NOTICE to all other clients upon authenticated client disconnections (\"1\" for yes or \"0\" for no)\n"
+  "alertautheddisconnect = \"1\"\n";
 
   // Write complete string to file
   if ((fprintf(fp, "%s", string)) < 0) {
diff --git a/functions.c b/functions.c
index d0c0341..c3e9c94 100644
--- a/functions.c
+++ b/functions.c
@@ -633,13 +633,10 @@ int disconnectclient(int fd, struct client *clients, struct ircdstate *ircdstate
   }
   debugprint(DEBUG_SOME, "disconnectclient(): disconnecting client %s with fd '%d'\n", clients[clientindex].remoteip, fd);
 
-  // Alert other clients about the disconnection (don't send yet, we haven't removed from the clients array yet)
-  char alertmsg[MAXDATASIZE];
-  if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: client %s has disconnected.", ircdstate->ircnick, clients[clientindex].remoteip)) {
-    fprintf(stderr, "Error while preparing authentication failure NOTICE!\n");
-    debugprint(DEBUG_CRIT, "Error while preparing authentication failure NOTICE!\n");
-    alertmsg[0] = '\0';
-  }
+  // Record some properties of the disconnecting client before we remove it from the clients array
+  int discauthed = clients[clientindex].authed;
+  char *discremoteip = strdup(clients[clientindex].remoteip);
+
   // Remove the client from the clients array
   for (int i = 0; i < MAXCLIENTS; i++) {
     if (clients[i].fd == fd) {
@@ -670,20 +667,46 @@ int disconnectclient(int fd, struct client *clients, struct ircdstate *ircdstate
         // Finish up with OpenSSL if using client TLS
         SSL_free(clients[i].ssl);
       }
+
       // Close the socket
       close(fd);
-      // Now clients array is cleared, inform all other clients (source "0" since we trust this message)
-      sendtoallclients(clients, alertmsg, 0, settings);
+
       // If there are now no clients connected, record the time
       if (numclients(clients) == 0) {
         ircdstate->clientsnonetime = time(NULL);
       }
+
+      // Now clients array is cleared, inform all other clients about the disconnection (if enabled)
+      if (!discauthed && settings->alertunautheddisconnect) {
+        // Unauthenticated client disconnection alerts enabled and disconnecting client is not authenticated
+        char alertmsg[MAXDATASIZE];
+        if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: unauthenticated client %s has disconnected.", ircdstate->ircnick, discremoteip)) {
+          fprintf(stderr, "Error while preparing unauthenticated client disconnection NOTICE!\n");
+          debugprint(DEBUG_CRIT, "Error while preparing unauthenticated client disconnection NOTICE!\n");
+          alertmsg[0] = '\0';
+        }
+        // (source "0" since we trust this message)
+        sendtoallclients(clients, alertmsg, 0, settings);
+      } else if (discauthed && settings->alertautheddisconnect) {
+        // Authenticated client disconnection alerts enabled and disconnecting client is authenticated
+        char alertmsg[MAXDATASIZE];
+        if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: authenticated client %s has disconnected.", ircdstate->ircnick, discremoteip)) {
+          fprintf(stderr, "Error while preparing authenticated client disconnection NOTICE!\n");
+          debugprint(DEBUG_CRIT, "Error while preparing authenticated client disconnection NOTICE!\n");
+          alertmsg[0] = '\0';
+        }
+        // (source "0" since we trust this message)
+        sendtoallclients(clients, alertmsg, 0, settings);
+      }
+
+      free(discremoteip);
       return 1;
     }
   }
 
   // If we got here, we didn't find and clear the client
   // TODO - Do something with a failed return code
+  free(discremoteip);
   return 0;
 }
 
@@ -1231,6 +1254,51 @@ int rehash(struct settings *settings, char *failuremsg, SSL_CTX *ctx) {
     configure_openssl_context(ctx, settings->certfile, settings->keyfile);
   }
 
+  // Is alerting (NOTICE) upon a new connection enabled?
+  int oldalertconnect = settings->alertconnect;
+  settings->alertconnect = getconfint("alertconnect", settings->conffile);
+  if (errno == ECONFINT) {
+    settings->alertconnect = oldalertconnect;
+    strcpy(failuremsg, "error getting 'alertconnect' from configuration file");
+    return 0;
+  }
+
+  // Is alerting (NOTICE) upon a failed authentication enabled?
+  int oldalertauthfail = settings->alertauthfail;
+  settings->alertauthfail = getconfint("alertauthfail", settings->conffile);
+  if (errno == ECONFINT) {
+    settings->alertauthfail = oldalertauthfail;
+    strcpy(failuremsg, "error getting 'alertauthfail' from configuration file");
+    return 0;
+  }
+
+  // Is alerting (NOTICE) upon a successful authentication enabled?
+  int oldalertauthsuccess = settings->alertauthsuccess;
+  settings->alertauthsuccess = getconfint("alertauthsuccess", settings->conffile);
+  if (errno == ECONFINT) {
+    settings->alertauthsuccess = oldalertauthsuccess;
+    strcpy(failuremsg, "error getting 'alertauthsuccess' from configuration file");
+    return 0;
+  }
+
+  // Is alerting (NOTICE) upon unauthenticated client disconnections enabled?
+  int oldalertunautheddisconnect = settings->alertunautheddisconnect;
+  settings->alertunautheddisconnect = getconfint("alertunautheddisconnect", settings->conffile);
+  if (errno == ECONFINT) {
+    settings->alertunautheddisconnect = oldalertunautheddisconnect;
+    strcpy(failuremsg, "error getting 'alertunautheddisconnect' from configuration file");
+    return 0;
+  }
+
+  // Is alerting (NOTICE) upon authenticated client disconnections enabled?
+  int oldalertautheddisconnect = settings->alertautheddisconnect;
+  settings->alertautheddisconnect = getconfint("alertautheddisconnect", settings->conffile);
+  if (errno == ECONFINT) {
+    settings->alertautheddisconnect = oldalertautheddisconnect;
+    strcpy(failuremsg, "error getting 'alertautheddisconnect' from configuration file");
+    return 0;
+  }
+
   // All is good, no failure message, return 1.
   failuremsg[0] = '\0';
   return 1;
diff --git a/message.c b/message.c
index 6f4c9dd..7e5497e 100644
--- a/message.c
+++ b/message.c
@@ -905,16 +905,18 @@ int processclientmessage(SSL *server_ssl, char *str, struct client *clients, int
           // Found client in array, set to authenticated
           clients[i].authed = 1;
           debugprint(DEBUG_FULL, "Found and authenticated fd in arr_authed.\n");
-          // Alert other clients about the successful authentication
-          char alertmsg[MAXDATASIZE];
-          if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client %s has successfully authenticated.", ircdstate->ircnick,
-              clients[clientindex].remoteip)) {
-            fprintf(stderr, "Error while preparing authentication success NOTICE!\n");
-            debugprint(DEBUG_CRIT, "Error while preparing authentication success NOTICE!\n");
-            alertmsg[0] = '\0';
+          // Alert other clients about the successful authentication (if enabled)
+          if (settings->alertauthsuccess) {
+            char alertmsg[MAXDATASIZE];
+            if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client %s has successfully authenticated.", ircdstate->ircnick,
+                clients[clientindex].remoteip)) {
+              fprintf(stderr, "Error while preparing authentication success NOTICE!\n");
+              debugprint(DEBUG_CRIT, "Error while preparing authentication success NOTICE!\n");
+              alertmsg[0] = '\0';
+            }
+            // "except" the current fd - we can use this as "except/sourcefd" since we set them as authed just above
+            sendtoallclients(clients, alertmsg, sourcefd, settings);
           }
-          // "except" the current fd - we can use this as "except/sourcefd" since we set them as authed just above
-          sendtoallclients(clients, alertmsg, sourcefd, settings);
         }
       }
     } else {
@@ -924,15 +926,17 @@ int processclientmessage(SSL *server_ssl, char *str, struct client *clients, int
       strncpy(remoteip, clients[clientindex].remoteip, INET6_ADDRSTRLEN);
       debugprint(DEBUG_SOME, "Password rejected, disconnecting client %s with fd %d.\n", remoteip, sourcefd);
       disconnectclient(sourcefd, clients, ircdstate, settings, clientcodes);
-      // Alert other clients about the failed authentication
-      char alertmsg[MAXDATASIZE];
-      if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client %s failed to authenticate.", ircdstate->ircnick, remoteip)) {
-        fprintf(stderr, "Error while preparing authentication failure NOTICE!\n");
-        debugprint(DEBUG_CRIT, "Error while preparing authentication failure NOTICE!\n");
-        alertmsg[0] = '\0';
-      }
-      // "except" 0 since we trust this message
-      sendtoallclients(clients, alertmsg, 0, settings);
+      // Alert other clients about the failed authentication (if enabled)
+      if (settings->alertauthfail) {
+        char alertmsg[MAXDATASIZE];
+        if (!snprintf(alertmsg, MAXDATASIZE, "NOTICE %s :blabouncer: new client %s failed to authenticate.", ircdstate->ircnick, remoteip)) {
+          fprintf(stderr, "Error while preparing authentication failure NOTICE!\n");
+          debugprint(DEBUG_CRIT, "Error while preparing authentication failure NOTICE!\n");
+          alertmsg[0] = '\0';
+        }
+        // "except" 0 since we trust this message
+        sendtoallclients(clients, alertmsg, 0, settings);
+      }
     }
 
     return 1;
diff --git a/structures.h b/structures.h
index d070638..b2585bd 100644
--- a/structures.h
+++ b/structures.h
@@ -83,6 +83,11 @@ struct settings {
   int debugkeep;
   int background; // Whether or not we're running in the background (detached from the terminal as a daemon)
   int replaydates; // Whether or not to include datestamps when replaying the replay log
+  int alertconnect;
+  int alertauthfail;
+  int alertauthsuccess;
+  int alertunautheddisconnect;
+  int alertautheddisconnect;
 };
 
 // Structure of a connected client, their socket/file descriptors, their authentication status, and their OpenSSL structures