X-Git-Url: https://code.citadel.org/?a=blobdiff_plain;f=citadel%2Fmodules%2Fxmpp%2Fserv_xmpp.c;h=374c4914277febee7937e90db62bb2708b22ab4e;hb=7a4aaaf5d40c2992763ac992e840edd4efbe4623;hp=8c7297350b2cb976ac8f66e10c553ed23595a68f;hpb=37d26a3d25048a08463d6230b6f8149f417ac150;p=citadel.git diff --git a/citadel/modules/xmpp/serv_xmpp.c b/citadel/modules/xmpp/serv_xmpp.c index 8c7297350..374c49142 100644 --- a/citadel/modules/xmpp/serv_xmpp.c +++ b/citadel/modules/xmpp/serv_xmpp.c @@ -1,10 +1,8 @@ /* - * $Id$ - * * 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. @@ -59,12 +57,96 @@ #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; -/* We have just received a tag from the client, so send them ours */ +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 + * pointer to the target buffer for convenience. + * + * BUG: this does not properly handle UTF-8 + */ +char *xmlesc(char *buf, char *str, int bufsiz) +{ + char *ptr; + unsigned char ch; + int len = 0; + + if (!buf) return(NULL); + buf[0] = 0; + len = 0; + if (!str) { + return(buf); + } + + for (ptr=str; *ptr; ptr++) { + ch = *ptr; + if (ch == '<') { + strcpy(&buf[len], "<"); + len += 4; + } + else if (ch == '>') { + strcpy(&buf[len], ">"); + len += 4; + } + else if (ch == '&') { + strcpy(&buf[len], "&"); + len += 5; + } + else if ((ch >= 0x20) && (ch <= 0x7F)) { + buf[len++] = ch; + buf[len] = 0; + } + else if (ch < 0x20) { + /* we probably shouldn't be doing this */ + buf[len++] = '_'; + buf[len] = 0; + } + else { + char oct[10]; + sprintf(oct, "&#%o;", ch); + strcpy(&buf[len], oct); + len += strlen(oct); + } + if ((len + 6) > bufsiz) { + return(buf); + } + } + return(buf); +} + +/* + * We have just received a tag from the client, so send them ours + */ void xmpp_stream_start(void *data, const char *supplied_el, const char **attr) { + char xmlbuf[256]; + while (*attr) { if (!strcasecmp(attr[0], "to")) { safestrncpy(XMPP->server_name, attr[1], sizeof XMPP->server_name); @@ -75,7 +157,7 @@ void xmpp_stream_start(void *data, const char *supplied_el, const char **attr) cprintf(""); cprintf("server_name); + cprintf("from=\"%s\" ", xmlesc(xmlbuf, XMPP->server_name, sizeof xmlbuf)); cprintf("id=\"%08x\" ", CC->cs_pid); cprintf("version=\"1.0\" "); cprintf("xmlns:stream=\"http://etherx.jabber.org/streams\" "); @@ -84,8 +166,10 @@ void xmpp_stream_start(void *data, const char *supplied_el, const char **attr) /* The features of this stream are... */ cprintf(""); -#ifdef HAVE_OPENSSL_XXXX_COMMENTED_OUT - /* TLS encryption (but only if it isn't already active) */ + /* + * TLS encryption (but only if it isn't already active) + */ +#ifdef HAVE_OPENSSL if (!CC->redirect_ssl) { cprintf(""); } @@ -121,9 +205,9 @@ void xmpp_xml_start(void *data, const char *supplied_el, const char **attr) { } /* - CtdlLogPrintf(CTDL_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) { - CtdlLogPrintf(CTDL_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 */ @@ -184,6 +268,7 @@ void xmpp_xml_start(void *data, const char *supplied_el, const char **attr) { void xmpp_xml_end(void *data, const char *supplied_el) { char el[256]; char *sep = NULL; + char xmlbuf[256]; /* Axe the namespace, we don't care about it */ safestrncpy(el, supplied_el, sizeof el); @@ -192,9 +277,9 @@ void xmpp_xml_end(void *data, const char *supplied_el) { } /* - CtdlLogPrintf(CTDL_DEBUG, "XMPP ELEMENT END : <%s>\n", el); + XMPP_syslog(LOG_DEBUG, "XMPP ELEMENT END : <%s>\n", el); if (XMPP->chardata_len > 0) { - CtdlLogPrintf(CTDL_DEBUG, " chardata: %s\n", XMPP->chardata); + XMPP_syslog(LOG_DEBUG, " chardata: %s\n", XMPP->chardata); } uncomment for more verbosity */ @@ -243,23 +328,23 @@ void xmpp_xml_end(void *data, const char *supplied_el) { else if (XMPP->ping_requested) { cprintf("iq_from)) { - cprintf("to=\"%s\" ", XMPP->iq_from); + cprintf("to=\"%s\" ", xmlesc(xmlbuf, XMPP->iq_from, sizeof xmlbuf)); } if (!IsEmptyStr(XMPP->iq_to)) { - cprintf("from=\"%s\" ", XMPP->iq_to); + cprintf("from=\"%s\" ", xmlesc(xmlbuf, XMPP->iq_to, sizeof xmlbuf)); } - cprintf("id=\"%s\"/>", XMPP->iq_id); + cprintf("id=\"%s\"/>", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf)); } /* * Unknown query ... return the XML equivalent of a blank stare */ else { - CtdlLogPrintf(CTDL_DEBUG, - "Unknown query <%s> - returning \n", - el + XMPP_syslog(LOG_DEBUG, + "Unknown query <%s> - returning \n", + el ); - cprintf("", XMPP->iq_id); + cprintf("", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf)); cprintf("" "" "" @@ -304,21 +389,21 @@ void xmpp_xml_end(void *data, const char *supplied_el) { /* Tell the client what its JID is */ - cprintf("", XMPP->iq_id); + cprintf("", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf)); cprintf(""); - cprintf("%s", XMPP->client_jid); + cprintf("%s", xmlesc(xmlbuf, XMPP->client_jid, sizeof xmlbuf)); cprintf(""); cprintf(""); } else if (XMPP->iq_session) { - cprintf("", XMPP->iq_id); + cprintf("", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf)); cprintf(""); } else { - cprintf("", XMPP->iq_id); - cprintf("Don't know howto do '%s'!", XMPP->iq_type); + cprintf("", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf)); + cprintf("Don't know howto do '%s'!", xmlesc(xmlbuf, XMPP->iq_type, sizeof xmlbuf)); cprintf(""); } @@ -378,10 +463,10 @@ void xmpp_xml_end(void *data, const char *supplied_el) { #ifdef HAVE_OPENSSL cprintf(""); CtdlModuleStartCryptoMsgs(NULL, NULL, NULL); - if (!CC->redirect_ssl) CC->kill_me = 1; + if (!CC->redirect_ssl) CC->kill_me = KILLME_NO_CRYPTO; #else cprintf(""); - CC->kill_me = 1; + CC->kill_me = KILLME_NO_CRYPTO; #endif } @@ -390,14 +475,14 @@ void xmpp_xml_end(void *data, const char *supplied_el) { } else if (!strcasecmp(el, "stream")) { - CtdlLogPrintf(CTDL_DEBUG, "XMPP client shut down their stream\n"); + XMPPM_syslog(LOG_DEBUG, "XMPP client shut down their stream\n"); xmpp_massacre_roster(); cprintf("\n"); - CC->kill_me = 1; + CC->kill_me = KILLME_CLIENT_LOGGED_OUT; } else { - CtdlLogPrintf(CTDL_DEBUG, "Ignoring unknown tag <%s>\n", el); + XMPP_syslog(LOG_DEBUG, "Ignoring unknown tag <%s>\n", el); } XMPP->chardata_len = 0; @@ -452,6 +537,7 @@ void xmpp_cleanup_function(void) { * Here's where our XMPP session begins its happy day. */ void xmpp_greeting(void) { + client_set_inbound_buf(4); strcpy(CC->cs_clientname, "XMPP session"); CC->session_specific_data = malloc(sizeof(citxmpp)); memset(XMPP, 0, sizeof(citxmpp)); @@ -461,8 +547,8 @@ void xmpp_greeting(void) { XMPP->xp = XML_ParserCreateNS("UTF-8", ':'); if (XMPP->xp == NULL) { - CtdlLogPrintf(CTDL_ALERT, "Cannot create XML parser!\n"); - CC->kill_me = 1; + XMPPM_syslog(LOG_ALERT, "Cannot create XML parser!\n"); + CC->kill_me = KILLME_XML_PARSER; return; } @@ -470,6 +556,17 @@ void xmpp_greeting(void) { 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 */ } @@ -487,8 +584,8 @@ void xmpp_command_loop(void) { XML_Parse(XMPP->xp, ChrPtr(stream_input), rc, 0); } else { - CtdlLogPrintf(CTDL_ERR, "Client disconnected: ending session.\n"); - CC->kill_me = 1; + XMPPM_syslog(LOG_ERR, "client disconnected: ending session.\n"); + CC->kill_me = KILLME_CLIENT_DISCONNECTED; } FreeStrBuf(&stream_input); } @@ -519,8 +616,12 @@ void xmpp_logout_hook(void) { } +void LogXMPPSrvDebugEnable(const int n) +{ + XMPPSrvDebugEnable = n; +} const char *CitadelServiceXMPP="XMPP"; - +extern void xmpp_cleanup_events(void); CTDL_MODULE_INIT(xmpp) { if (!threading) { @@ -531,13 +632,16 @@ CTDL_MODULE_INIT(xmpp) xmpp_async_loop, CitadelServiceXMPP ); + CtdlRegisterDebugFlagHook(HKEY("serv_xmpp"), LogXMPPSrvDebugEnable, &XMPPSrvDebugEnable); 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); + CtdlRegisterCleanupHook(xmpp_cleanup_events); + } - /* return our Subversion id for the Log */ - return "$Id$"; + /* return our module name for the log */ + return "xmpp"; }