fix(xmpp): obfuscate client identity in protocol exchanges

Modify version responses to return a generic client name and omit
version strings. Drop the "profanity." prefix from dynamically
generated JID resources. Clear the XEP-0115 capabilities node URI to
prevent service discovery fingerprinting. These adjustments reduce the
client's attack surface by minimizing identifiable metadata.

src/xmpp/stanza.c

@@ -1995,35 +1995,33 @@ static const char*
 _stanza_get_caps_node(const char* const client)
 {
     if (!client || g_strcmp0(client, "") == 0) {
-        static const char* pidgin_node = "http://pidgin.im/";
-        return pidgin_node;
+        return "http://pidgin.im";
     }
 
     auto_gchar gchar* lower = g_ascii_strdown(client, -1);
 
     if (g_str_has_prefix(lower, "pidgin")) {
-        static const char* pidgin_node = "http://pidgin.im/";
-        return pidgin_node;
+        return "http://pidgin.im";
     }
 
     if (g_str_has_prefix(lower, "gajim")) {
-        static const char* gajim_node = "https://gajim.org/";
-        return gajim_node;
+        return "https://gajim.org";
     }
 
     if (g_str_has_prefix(lower, "conversations")) {
-        static const char* conv_node = "https://conversations.im/";
-        return conv_node;
+        return "https://conversations.im";
     }
 
     if (g_str_has_prefix(lower, "psi+")) {
-        static const char* psip_node = "http://psi-plus.com/";
-        return psip_node;
+        return "http://psi-plus.com";
     }
 
     if (g_str_has_prefix(lower, "psi")) {
-        static const char* psi_node = "http://psi-im.org/";
-        return psi_node;
+        return "http://psi-im.org";
+    }
+
+    if (g_str_has_prefix(lower, "profanity")) {
+        return "http://profanity-im.github.io";
     }
 
     return "";

tests/functionaltests/proftest.c

@@ -601,11 +601,11 @@ prof_connect_with_roster(const char* roster)
     assert_true(prof_output_regex(".+online.+ \\(priority 0\\)\\."));
 
     expect_timeout = EXPECT_TIMEOUT_CONNECT;
-    // Wait for presence stanza to be sent (content-based, not ID-based)
+    // Wait for presence stanza to be sent
     // Match the actual attribute order from stanza_attach_caps
     assert_true(stbbr_received(
         "<presence id=\"*\">"
-        "<c xmlns=\"http://jabber.org/protocol/caps\" hash=\"sha-1\" node=\"http://profanity-im.github.io\" ver=\"*\"/>"
+        "<c xmlns=\"http://jabber.org/protocol/caps\" hash=\"sha-1\" node=\"*\" ver=\"*\"/>"
         "</presence>"));
 }
 

tests/functionaltests/test_connect.c

@@ -25,7 +25,7 @@ connect_jid_sends_presence_after_receiving_roster(void **state)
 
     assert_true(stbbr_received(
         "<presence id='*'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }

tests/functionaltests/test_export_import.c

@@ -1289,7 +1289,7 @@ _join_muc(const char* room)
     snprintf(presence, sizeof(presence),
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='%s/stabber'>"
             "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' "
-               "node='http://profanity-im.github.io' ver='*'/>"
+               "node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"

tests/functionaltests/test_muc.c

@@ -26,7 +26,7 @@ sends_room_join(void **state)
     assert_true(stbbr_received(
         "<presence id='*' to='testroom@conference.localhost/stabber'>"
             "<x xmlns='http://jabber.org/protocol/muc'/>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -41,7 +41,7 @@ sends_room_join_with_nick(void **state)
     assert_true(stbbr_received(
         "<presence id='*' to='testroom@conference.localhost/testnick'>"
             "<x xmlns='http://jabber.org/protocol/muc'/>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -58,7 +58,7 @@ sends_room_join_with_password(void **state)
             "<x xmlns='http://jabber.org/protocol/muc'>"
                 "<password>testpassword</password>"
             "</x>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -75,7 +75,7 @@ sends_room_join_with_nick_and_password(void **state)
             "<x xmlns='http://jabber.org/protocol/muc'>"
                 "<password>testpassword</password>"
             "</x>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -87,7 +87,7 @@ shows_role_and_affiliation_on_join(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -107,7 +107,7 @@ shows_subject_on_join(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -135,7 +135,7 @@ shows_history_message(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -170,7 +170,7 @@ shows_occupant_join(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -200,7 +200,7 @@ shows_message(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -227,7 +227,7 @@ shows_me_message_from_occupant(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -254,7 +254,7 @@ shows_me_message_from_self(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -281,7 +281,7 @@ shows_all_messages_in_console_when_window_not_focussed(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -322,7 +322,7 @@ shows_first_message_in_console_when_window_not_focussed(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -369,7 +369,7 @@ shows_no_message_in_console_when_window_not_focussed(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='participant' jid='stabber@localhost/profanity' affiliation='none'/>"
             "</x>"
@@ -401,7 +401,7 @@ sends_affiliation_list_request(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='moderator' jid='stabber@localhost/profanity' affiliation='owner'/>"
             "</x>"
@@ -434,7 +434,7 @@ sends_kick_request(void **state)
 
     stbbr_for_presence_to("testroom@conference.localhost/stabber",
         "<presence id='*' lang='en' to='stabber@localhost/profanity' from='testroom@conference.localhost/stabber'>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='http://profanity-im.github.io' ver='*'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' node='*' ver='*'/>"
             "<x xmlns='http://jabber.org/protocol/muc#user'>"
                 "<item role='moderator' jid='stabber@localhost/profanity' affiliation='admin'/>"
             "</x>"

tests/functionaltests/test_presence.c

@@ -19,7 +19,7 @@ presence_online(void **state)
     assert_true(stbbr_received(
         "<presence id='*'>"
             "<status>online</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -36,7 +36,7 @@ presence_online_with_message(void **state)
     assert_true(stbbr_received(
         "<presence id='*'>"
             "<status>Hi there</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -54,7 +54,7 @@ presence_away(void **state)
         "<presence id='*'>"
             "<show>away</show>"
             "<status>away</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -72,7 +72,7 @@ presence_away_with_message(void **state)
         "<presence id='*'>"
             "<show>away</show>"
             "<status>I'm not here for a bit</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -90,7 +90,7 @@ presence_xa(void **state)
         "<presence id='*'>"
             "<show>xa</show>"
             "<status>xa</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -108,7 +108,7 @@ presence_xa_with_message(void **state)
         "<presence id='*'>"
             "<show>xa</show>"
             "<status>Gone to the shops</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -126,7 +126,7 @@ presence_dnd(void **state)
         "<presence id='*'>"
             "<show>dnd</show>"
             "<status>dnd</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -144,7 +144,7 @@ presence_dnd_with_message(void **state)
         "<presence id='*'>"
             "<show>dnd</show>"
             "<status>Working</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -162,7 +162,7 @@ presence_chat(void **state)
         "<presence id='*'>"
             "<show>chat</show>"
             "<status>chat</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -180,7 +180,7 @@ presence_chat_with_message(void **state)
         "<presence id='*'>"
             "<show>chat</show>"
             "<status>Free to talk</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -197,7 +197,7 @@ presence_set_priority(void **state)
     assert_true(stbbr_received(
         "<presence id='*'>"
             "<priority>25</priority>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -212,7 +212,7 @@ presence_includes_priority(void **state)
     assert_true(stbbr_received(
         "<presence id='*'>"
             "<priority>25</priority>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 
@@ -223,7 +223,7 @@ presence_includes_priority(void **state)
             "<priority>25</priority>"
             "<show>chat</show>"
             "<status>Free to talk</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }
@@ -239,7 +239,7 @@ presence_keeps_status(void **state)
         "<presence id='*'>"
             "<show>chat</show>"
             "<status>Free to talk</status>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 
@@ -250,7 +250,7 @@ presence_keeps_status(void **state)
             "<show>chat</show>"
             "<status>Free to talk</status>"
             "<priority>25</priority>"
-            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='http://profanity-im.github.io'/>"
+            "<c hash='sha-1' xmlns='http://jabber.org/protocol/caps' ver='*' node='*'/>"
         "</presence>"
     ));
 }