* Properly escape XML output using new xmlesc() function for XMPP sessions. This...

[citadel.git] / citadel / modules / xmpp / serv_xmpp.c

diff --git a/citadel/modules/xmpp/serv_xmpp.c b/citadel/modules/xmpp/serv_xmpp.c
index 8c7297350b2cb976ac8f66e10c553ed23595a68f..d9271e46469235b1fdc731e47bd6186e7f7a6d4b 100644 (file)
--- a/citadel/modules/xmpp/serv_xmpp.c
+++ b/citadel/modules/xmpp/serv_xmpp.c
@@ -61,10 +61,65 @@
 
 struct xmpp_event *xmpp_queue = NULL;
 
-/* We have just received a <stream> tag from the client, so send them ours */
+/*
+ * 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], "&lt;");
+                       len += 4;
+               }
+               else if (ch == '>') {
+                       strcpy(&buf[len], "&gt;");
+                       len += 4;
+               }
+               else if (ch == '&') {
+                       strcpy(&buf[len], "&amp;");
+                       len += 5;
+               }
+               else if (ch <= 0x7F) {
+                       buf[len++] = ch;
+                       buf[len] = 0;
+               }
+               else if (ch > 0x7F) {
+                       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 <stream> 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 +130,7 @@ void xmpp_stream_start(void *data, const char *supplied_el, const char **attr)
        cprintf("<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
 
        cprintf("<stream:stream ");
-       cprintf("from=\"%s\" ", XMPP->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\" ");
@@ -184,6 +239,7 @@ 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);
@@ -243,12 +299,12 @@ void xmpp_xml_end(void *data, const char *supplied_el) {
                        else if (XMPP->ping_requested) {
                                cprintf("<iq type=\"result\" ");
                                if (!IsEmptyStr(XMPP->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));
                        }
 
                        /*
@@ -259,7 +315,7 @@ void xmpp_xml_end(void *data, const char *supplied_el) {
                                        "Unknown query <%s> - returning <service-unavailable/>\n",
                                        el
                                );
-                               cprintf("<iq type=\"error\" id=\"%s\">", XMPP->iq_id);
+                               cprintf("<iq type=\"error\" id=\"%s\">", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf));
                                cprintf("<error code=\"503\" type=\"cancel\">"
                                        "<service-unavailable xmlns=\"urn:ietf:params:xml:ns:xmpp-stanzas\"/>"
                                        "</error>"
@@ -304,21 +360,21 @@ void xmpp_xml_end(void *data, const char *supplied_el) {
 
                        /* Tell the client what its JID is */
 
-                       cprintf("<iq type=\"result\" id=\"%s\">", XMPP->iq_id);
+                       cprintf("<iq type=\"result\" id=\"%s\">", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf));
                        cprintf("<bind xmlns=\"urn:ietf:params:xml:ns:xmpp-bind\">");
-                       cprintf("<jid>%s</jid>", XMPP->client_jid);
+                       cprintf("<jid>%s</jid>", xmlesc(xmlbuf, XMPP->client_jid, sizeof xmlbuf));
                        cprintf("</bind>");
                        cprintf("</iq>");
                }
 
                else if (XMPP->iq_session) {
-                       cprintf("<iq type=\"result\" id=\"%s\">", XMPP->iq_id);
+                       cprintf("<iq type=\"result\" id=\"%s\">", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf));
                        cprintf("</iq>");
                }
 
                else {
-                       cprintf("<iq type=\"error\" id=\"%s\">", XMPP->iq_id);
-                       cprintf("<error>Don't know howto do '%s'!</error>", XMPP->iq_type);
+                       cprintf("<iq type=\"error\" id=\"%s\">", xmlesc(xmlbuf, XMPP->iq_id, sizeof xmlbuf));
+                       cprintf("<error>Don't know howto do '%s'!</error>", xmlesc(xmlbuf, XMPP->iq_type, sizeof xmlbuf));
                        cprintf("</iq>");
                }