/*
* XMPP (Jabber) service for the Citadel system
- * Copyright (c) 2007-2010 by Art Cancro
+ * Copyright (c) 2007-2011 by Art Cancro
*
- * This program is free software; you can redistribute it and/or modify
+ * This program is open source software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
#include "ctdl_module.h"
#include "serv_xmpp.h"
+/* XML_StopParser is present in expat 2.x */
+#if XML_MAJOR_VERSION > 1
+#define HAVE_XML_STOPPARSER
+#endif
+
struct xmpp_event *xmpp_queue = NULL;
+int XMPPSrvDebugEnable = 0;
+
+
+
+#ifdef HAVE_XML_STOPPARSER
+/* Stop the parser if an entity declaration is hit. */
+static void xmpp_entity_declaration(void *userData, const XML_Char *entityName,
+ int is_parameter_entity, const XML_Char *value,
+ int value_length, const XML_Char *base,
+ const XML_Char *systemId, const XML_Char *publicId,
+ const XML_Char *notationName
+) {
+ XMPPM_syslog(LOG_WARNING, "Illegal entity declaration encountered; stopping parser.");
+ XML_StopParser(XMPP->xp, XML_FALSE);
+}
+#endif
+
+
+
/*
* Given a source string and a target buffer, returns the string
* properly escaped for insertion into an XML stream. Returns a
}
/*
- syslog(LOG_DEBUG, "XMPP ELEMENT START: <%s>\n", el);
+ XMPP_syslog(LOG_DEBUG, "XMPP ELEMENT START: <%s>\n", el);
for (i=0; attr[i] != NULL; i+=2) {
- syslog(LOG_DEBUG, " Attribute '%s' = '%s'\n", attr[i], attr[i+1]);
+ XMPP_syslog(LOG_DEBUG, " Attribute '%s' = '%s'\n", attr[i], attr[i+1]);
}
uncomment for more verbosity */
}
/*
- syslog(LOG_DEBUG, "XMPP ELEMENT END : <%s>\n", el);
+ XMPP_syslog(LOG_DEBUG, "XMPP ELEMENT END : <%s>\n", el);
if (XMPP->chardata_len > 0) {
- syslog(LOG_DEBUG, " chardata: %s\n", XMPP->chardata);
+ XMPP_syslog(LOG_DEBUG, " chardata: %s\n", XMPP->chardata);
}
uncomment for more verbosity */
* Unknown query ... return the XML equivalent of a blank stare
*/
else {
- syslog(LOG_DEBUG,
- "Unknown query <%s> - returning <service-unavailable/>\n",
- el
+ XMPP_syslog(LOG_DEBUG,
+ "Unknown query <%s> - returning <service-unavailable/>\n",
+ el
);
cprintf("<iq type=\"error\" id=\"%s\">", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf));
cprintf("<error code=\"503\" type=\"cancel\">"
}
else if (!strcasecmp(el, "stream")) {
- syslog(LOG_DEBUG, "XMPP client shut down their stream\n");
+ XMPPM_syslog(LOG_DEBUG, "XMPP client shut down their stream\n");
xmpp_massacre_roster();
cprintf("</stream>\n");
CC->kill_me = KILLME_CLIENT_LOGGED_OUT;
}
else {
- syslog(LOG_DEBUG, "Ignoring unknown tag <%s>\n", el);
+ XMPP_syslog(LOG_DEBUG, "Ignoring unknown tag <%s>\n", el);
}
XMPP->chardata_len = 0;
XMPP->xp = XML_ParserCreateNS("UTF-8", ':');
if (XMPP->xp == NULL) {
- syslog(LOG_ALERT, "Cannot create XML parser!\n");
+ XMPPM_syslog(LOG_ALERT, "Cannot create XML parser!\n");
CC->kill_me = KILLME_XML_PARSER;
return;
}
XML_SetCharacterDataHandler(XMPP->xp, xmpp_xml_chardata);
// XML_SetUserData(XMPP->xp, something...);
+ /* Prevent the "billion laughs" attack against expat by disabling
+ * internal entity expansion. With 2.x, forcibly stop the parser
+ * if an entity is declared - this is safer and a more obvious
+ * failure mode. With older versions, simply prevent expansion
+ * of such entities. */
+#ifdef HAVE_XML_STOPPARSER
+ XML_SetEntityDeclHandler(XMPP->xp, xmpp_entity_declaration);
+#else
+ XML_SetDefaultHandler(XMPP->xp, NULL);
+#endif
+
CC->can_receive_im = 1; /* This protocol is capable of receiving instant messages */
}
XML_Parse(XMPP->xp, ChrPtr(stream_input), rc, 0);
}
else {
- syslog(LOG_ERR, "Client disconnected: ending session.\n");
+ XMPPM_syslog(LOG_ERR, "client disconnected: ending session.\n");
CC->kill_me = KILLME_CLIENT_DISCONNECTED;
}
FreeStrBuf(&stream_input);
}
+void LogXMPPSrvDebugEnable(const int n)
+{
+ XMPPSrvDebugEnable = n;
+}
const char *CitadelServiceXMPP="XMPP";
extern void xmpp_cleanup_events(void);
CTDL_MODULE_INIT(xmpp)
xmpp_async_loop,
CitadelServiceXMPP
);
- CtdlRegisterSessionHook(xmpp_cleanup_function, EVT_STOP);
- CtdlRegisterSessionHook(xmpp_login_hook, EVT_LOGIN);
- CtdlRegisterSessionHook(xmpp_logout_hook, EVT_LOGOUT);
- CtdlRegisterSessionHook(xmpp_login_hook, EVT_UNSTEALTH);
- CtdlRegisterSessionHook(xmpp_logout_hook, EVT_STEALTH);
+ CtdlRegisterDebugFlagHook(HKEY("serv_xmpp"), LogXMPPSrvDebugEnable, &XMPPSrvDebugEnable);
+ CtdlRegisterSessionHook(xmpp_cleanup_function, EVT_STOP, PRIO_STOP + 70);
+ CtdlRegisterSessionHook(xmpp_login_hook, EVT_LOGIN, PRIO_LOGIN + 90);
+ CtdlRegisterSessionHook(xmpp_logout_hook, EVT_LOGOUT, PRIO_LOGOUT + 90);
+ CtdlRegisterSessionHook(xmpp_login_hook, EVT_UNSTEALTH, PRIO_UNSTEALTH + 1);
+ CtdlRegisterSessionHook(xmpp_logout_hook, EVT_STEALTH, PRIO_STEALTH + 1);
CtdlRegisterCleanupHook(xmpp_cleanup_events);
}
- /* return our Subversion id for the Log */
+ /* return our module name for the log */
return "xmpp";
}