2 // This file contains functions which handle all of the CalDAV "REPORT" queries
3 // specified in RFC4791 section 7.
5 // Copyright (c) 2021 by the citadel.org team
7 // This program is open source software. It runs great on the
8 // Linux operating system (and probably elsewhere). You can use,
9 // copy, and run it under the terms of the GNU General Public
12 // This program is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 // GNU General Public License for more details.
20 // A CalDAV REPORT can only be one type. This is stored in the report_type member.
28 // Data type for CalDAV Report Parameters.
29 // As we slog our way through the XML we learn what the client is asking for
30 // and build up the contents of this data type.
32 int tag_nesting_level; // not needed, just kept for pretty-printing
33 enum cr_type report_type; // which RFC4791 section 7 REPORT are we generating
34 StrBuf *Chardata; // XML chardata in between tags is built up here
35 StrBuf *Hrefs; // list of items requested by a calendar-multiget report
39 // XML parser callback
40 void caldav_xml_start(void *data, const char *el, const char **attr) {
41 struct cr_parms *crp = (struct cr_parms *) data;
44 // syslog(LOG_DEBUG, "CALDAV ELEMENT START: <%s> %d", el, crp->tag_nesting_level);
46 for (i = 0; attr[i] != NULL; i += 2) {
47 syslog(LOG_DEBUG, " Attribute '%s' = '%s'", attr[i], attr[i + 1]);
50 if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-multiget")) {
51 crp->report_type = cr_calendar_multiget;
54 else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-query")) {
55 crp->report_type = cr_calendar_query;
58 else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:free-busy-query")) {
59 crp->report_type = cr_freebusy_query;
62 ++crp->tag_nesting_level;
66 // XML parser callback
67 void caldav_xml_end(void *data, const char *el) {
68 struct cr_parms *crp = (struct cr_parms *) data;
69 --crp->tag_nesting_level;
71 if (crp->Chardata != NULL) {
72 // syslog(LOG_DEBUG, "CALDAV CHARDATA : %s", ChrPtr(crp->Chardata));
74 // syslog(LOG_DEBUG, "CALDAV ELEMENT END : <%s> %d", el, crp->tag_nesting_level);
76 if ((!strcasecmp(el, "DAV::href")) || (!strcasecmp(el, "DAV:href"))) {
77 if (crp->Hrefs == NULL) { // append crp->Chardata to crp->Hrefs
78 crp->Hrefs = NewStrBuf();
81 StrBufAppendBufPlain(crp->Hrefs, HKEY("|"), 0);
83 StrBufAppendBuf(crp->Hrefs, crp->Chardata, 0);
86 if (crp->Chardata != NULL) { // Tag is closed; chardata is now out of scope.
87 FreeStrBuf(&crp->Chardata); // Free the buffer.
93 // XML parser callback
94 void caldav_xml_chardata(void *data, const XML_Char * s, int len) {
95 struct cr_parms *crp = (struct cr_parms *) data;
97 if (crp->Chardata == NULL) {
98 crp->Chardata = NewStrBuf();
101 StrBufAppendBufPlain(crp->Chardata, s, len, 0);
107 // Called by caldav_response() to fetch a message (by number) in the current room,
108 // and return only the icalendar data as a StrBuf. Returns NULL if not found.
110 // NOTE: this function expects that "MSGP text/calendar" was issued at the beginning
111 // of a REPORT operation to set our preferred MIME type to calendar data.
112 StrBuf *fetch_ical(struct ctdlsession * c, long msgnum) {
116 ctdl_printf(c, "MSG4 %ld", msgnum);
117 ctdl_readline(c, buf, sizeof(buf));
122 while (ctdl_readline(c, buf, sizeof(buf)), strcmp(buf, "000")) {
123 if (Buf != NULL) { // already in body
124 StrBufAppendPrintf(Buf, "%s\n", buf);
126 else if (IsEmptyStr(buf)) { // beginning of body
133 // webcit[13039]: msgn=53CE87AF-00392161@uncensored.citadel.org
134 // webcit[13039]: path=IGnatius T Foobar
135 // webcit[13039]: time=1208008800
136 // webcit[13039]: from=IGnatius T Foobar
137 // webcit[13039]: room=0000000001.Calendar
138 // webcit[13039]: node=uncnsrd
139 // webcit[13039]: hnod=Uncensored
140 // webcit[13039]: exti=040000008200E00074C5B7101A82E0080000000080C728F83E84C801000000000000000010000000E857E0DC57F53947ADF0BB91EE3A502F
141 // webcit[13039]: subj==?UTF-8?B?V2VzbGV5J3MgYmlydGhkYXkgcGFydHk=
143 // webcit[13039]: part=||1||text/calendar|1127||
144 // webcit[13039]: text
145 // webcit[13039]: Content-type: text/calendar
146 // webcit[13039]: Content-length: 1127
147 // webcit[13039]: Content-transfer-encoding: 7bit
148 // webcit[13039]: X-Citadel-MSG4-Partnum: 1
150 // webcit[13039]: BEGIN:VCALENDAR
154 // Called by caldav_report() to output a single item.
155 // Our policy is to throw away the list of properties the client asked for, and just send everything.
156 void caldav_response(struct http_transaction *h, struct ctdlsession *c, StrBuf * ReportOut, StrBuf * ThisHref) {
158 StrBuf *Caldata = NULL;
161 euid = strrchr(ChrPtr(ThisHref), '/');
166 euid = (char *) ChrPtr(ThisHref);
169 char *unescaped_euid = strdup(euid);
172 unescape_input(unescaped_euid);
174 StrBufAppendPrintf(ReportOut, "<D:response>");
175 StrBufAppendPrintf(ReportOut, "<D:href>");
176 StrBufXMLEscAppend(ReportOut, ThisHref, NULL, 0, 0);
177 StrBufAppendPrintf(ReportOut, "</D:href>");
178 StrBufAppendPrintf(ReportOut, "<D:propstat>");
180 msgnum = locate_message_by_uid(c, unescaped_euid);
181 free(unescaped_euid);
183 Caldata = fetch_ical(c, msgnum);
186 if (Caldata != NULL) {
187 // syslog(LOG_DEBUG, "caldav_response(%s) 200 OK", ChrPtr(ThisHref));
188 StrBufAppendPrintf(ReportOut, "<D:status>");
189 StrBufAppendPrintf(ReportOut, "HTTP/1.1 200 OK");
190 StrBufAppendPrintf(ReportOut, "</D:status>");
191 StrBufAppendPrintf(ReportOut, "<D:prop>");
192 StrBufAppendPrintf(ReportOut, "<D:getetag>");
193 StrBufAppendPrintf(ReportOut, "%ld", msgnum);
194 StrBufAppendPrintf(ReportOut, "</D:getetag>");
195 StrBufAppendPrintf(ReportOut, "<C:calendar-data>");
196 StrBufXMLEscAppend(ReportOut, Caldata, NULL, 0, 0);
197 StrBufAppendPrintf(ReportOut, "</C:calendar-data>");
198 StrBufAppendPrintf(ReportOut, "</D:prop>");
199 FreeStrBuf(&Caldata);
203 // syslog(LOG_DEBUG, "caldav_response(%s) 404 not found", ChrPtr(ThisHref));
204 StrBufAppendPrintf(ReportOut, "<D:status>");
205 StrBufAppendPrintf(ReportOut, "HTTP/1.1 404 not found");
206 StrBufAppendPrintf(ReportOut, "</D:status>");
209 StrBufAppendPrintf(ReportOut, "</D:propstat>");
210 StrBufAppendPrintf(ReportOut, "</D:response>");
214 // Called by report_the_room_itself() in room_functions.c when a CalDAV REPORT method
215 // is requested on a calendar room. We fire up an XML Parser to decode the request and
216 // hopefully produce the correct output.
217 void caldav_report(struct http_transaction *h, struct ctdlsession *c) {
221 memset(&crp, 0, sizeof(struct cr_parms));
223 XML_Parser xp = XML_ParserCreateNS("UTF-8", ':');
225 syslog(LOG_INFO, "Cannot create XML parser!");
230 XML_SetElementHandler(xp, caldav_xml_start, caldav_xml_end);
231 XML_SetCharacterDataHandler(xp, caldav_xml_chardata);
232 XML_SetUserData(xp, &crp);
233 XML_SetDefaultHandler(xp, NULL); // Disable internal entity expansion to prevent "billion laughs attack"
234 XML_Parse(xp, h->request_body, h->request_body_length, 1);
237 if (crp.Chardata != NULL) { // Discard any trailing chardata ... normally nothing here
238 FreeStrBuf(&crp.Chardata);
242 // We're going to make a lot of MSG4 calls, and the preferred MIME type we want is "text/calendar".
243 // The iCalendar standard is mature now, and we are no longer interested in text/x-vcal or application/ics.
244 ctdl_printf(c, "MSGP text/calendar");
245 ctdl_readline(c, buf, sizeof buf);
247 // Now begin the REPORT.
248 syslog(LOG_DEBUG, "CalDAV REPORT type is: %d", crp.report_type);
249 StrBuf *ReportOut = NewStrBuf();
250 StrBufAppendPrintf(ReportOut, "<?xml version=\"1.0\" encoding=\"utf-8\"?>"
251 "<D:multistatus " "xmlns:D=\"DAV:\" " "xmlns:C=\"urn:ietf:params:xml:ns:caldav\"" ">");
253 if (crp.Hrefs != NULL) { // Output all qualifying calendar items!
254 StrBuf *ThisHref = NewStrBuf();
255 const char *pvset = NULL;
256 while (StrBufExtract_NextToken(ThisHref, crp.Hrefs, &pvset, '|') >= 0) {
257 caldav_response(h, c, ReportOut, ThisHref);
259 FreeStrBuf(&ThisHref);
260 FreeStrBuf(&crp.Hrefs);
264 StrBufAppendPrintf(ReportOut, "</D:multistatus>\n"); // End the REPORT.
266 add_response_header(h, strdup("Content-type"), strdup("text/xml"));
267 h->response_code = 207;
268 h->response_string = strdup("Multi-Status");
269 h->response_body_length = StrLength(ReportOut);
270 h->response_body = SmashStrBuf(&ReportOut);