-// This file contains functions which handle all of the CalDAV "REPORT" queries
-// specified in RFC4791 section 7.
-//
+// This file contains functions which handle all of the CalDAV "REPORT" queries specified in RFC4791 section 7.
// Copyright (c) 2023-2024 by the citadel.org team
-//
-// This program is open source software. Use, duplication, or
-// disclosure is subject to the GNU General Public License v3.
+// This program is open source software. Use, duplication, or disclosure is subject to the GNU General Public License v3.
#include "webcit.h"
+#define CALDAV "urn:ietf:params:xml:ns:caldav:" // Shorthand for the XML namespace of CalDAV
+#define CALDAVLEN sizeof(CALDAV)-1 // And the length of that string
+
+const char *the_beginning_of_time = "19010101T010101Z";
+const char *the_end_of_time = "99991231T235959Z";
// A CalDAV REPORT can only be one type. This is stored in the report_type member.
enum cr_type {
cr_freebusy_query
};
-
// Data type for CalDAV Report Parameters.
// As we slog our way through the XML we learn what the client is asking for
// and build up the contents of this data type.
-struct cr_parms {
- int tag_nesting_level; // not needed, just kept for pretty-printing
+struct cr_params {
+ int comp_filter_nesting_level;
enum cr_type report_type; // which RFC4791 section 7 REPORT are we generating
StrBuf *Chardata; // XML chardata in between tags is built up here
StrBuf *Hrefs; // list of items requested by a `calendar-multiget` REPORT
+ Array *filters; // If the query contains a FILTER stanza, the filter criteria are populated here
+ int filter_nest; // tag nesting level where a FILTER stanza begins
};
// XML parser callback
void caldav_xml_start(void *data, const char *el, const char **attr) {
- struct cr_parms *crp = (struct cr_parms *) data;
- int i;
+ struct cr_params *crp = (struct cr_params *) data;
- // syslog(LOG_DEBUG, "CALDAV ELEMENT START: <%s> %d", el, crp->tag_nesting_level);
-
- for (i = 0; attr[i] != NULL; i += 2) {
- syslog(LOG_DEBUG, " Attribute '%s' = '%s'", attr[i], attr[i + 1]);
+#ifdef DEBUG_XML_PARSE
+ // logging
+ syslog(LOG_DEBUG, "<%s>", el);
+ for (int i = 0; attr[i] != NULL; i += 2) {
+ syslog(LOG_DEBUG, "Attribute '%s' = '%s'", attr[i], attr[i + 1]);
}
+ // end logging
+#endif
// RFC4791 7.8 "calendar-query" REPORT - Client will send a lot of search criteria.
- if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-query")) {
+ if (!strcasecmp(el, CALDAV"calendar-query")) {
crp->report_type = cr_calendar_query;
}
// RFC4791 7.9 "calendar-multiget" REPORT - Client will supply a list of specific hrefs.
- else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-multiget")) {
+ else if (!strcasecmp(el, CALDAV"calendar-multiget")) {
crp->report_type = cr_calendar_multiget;
}
// RFC4791 7.10 "free-busy-query" REPORT
- else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:free-busy-query")) {
+ else if (!strcasecmp(el, CALDAV"free-busy-query")) {
crp->report_type = cr_freebusy_query;
}
- ++crp->tag_nesting_level;
+ // RFC4791 9.7 create a filter array if this query contains a "filter" stanza
+ else if (!strcasecmp(el, CALDAV"filter")) {
+ crp->filters = array_new(SIZ);
+ crp->filter_nest = crp->comp_filter_nesting_level;
+ }
+
+ // Handle the filters defined in RFC4791 9.7.1 through 9.7.5
+ else if ( ( (!strcasecmp(el, CALDAV"comp-filter"))
+ || (!strcasecmp(el, CALDAV"prop-filter"))
+ || (!strcasecmp(el, CALDAV"param-filter"))
+ || (!strcasecmp(el, CALDAV"is-not-defined"))
+ || (!strcasecmp(el, CALDAV"text-match"))
+ || (!strcasecmp(el, CALDAV"time-range"))
+ )
+ && (crp->filters) // Make sure we actually allocated an array
+ ) {
+
+ if (!strcasecmp(el, CALDAV"comp-filter")) {
+ ++crp->comp_filter_nesting_level;
+ }
+
+ char newfilter[SIZ];
+ int a = 0;
+ int len = snprintf(newfilter, SIZ, "%d|", crp->comp_filter_nesting_level - crp->filter_nest - 1);
+ len += snprintf(&newfilter[len], SIZ-len, "%s", &el[CALDAVLEN]); // filter name without the namespace
+ while (attr[a]) {
+ len += snprintf(&newfilter[len], SIZ-len, "|%s", attr[a++]); // now save the attributes
+ }
+ array_append(crp->filters, newfilter);
+ }
}
// XML parser callback
void caldav_xml_end(void *data, const char *el) {
- struct cr_parms *crp = (struct cr_parms *) data;
- --crp->tag_nesting_level;
+ struct cr_params *crp = (struct cr_params *) data;
- if (crp->Chardata != NULL) {
- // syslog(LOG_DEBUG, "CALDAV CHARDATA : %s", ChrPtr(crp->Chardata));
+#ifdef DEBUG_XML_PARSE
+ // logging
+ int i;
+ syslog(LOG_DEBUG, "</%s>", el);
+ // end logging
+#endif
+
+ if (!strcasecmp(el, CALDAV"comp-filter")) {
+ --crp->comp_filter_nesting_level;
}
- // syslog(LOG_DEBUG, "CALDAV ELEMENT END : <%s> %d", el, crp->tag_nesting_level);
+
if ((!strcasecmp(el, "DAV::href")) || (!strcasecmp(el, "DAV:href"))) {
if (crp->Hrefs == NULL) { // append crp->Chardata to crp->Hrefs
// XML parser callback
-void caldav_xml_chardata(void *data, const XML_Char * s, int len) {
- struct cr_parms *crp = (struct cr_parms *) data;
+void caldav_xml_chardata(void *data, const XML_Char *s, int len) {
+ struct cr_params *crp = (struct cr_params *) data;
+
+ char *app = malloc(len+1);
+ if (!app) {
+ return;
+ }
+ memcpy(app, s, len);
+ app[len] = 0;
if (crp->Chardata == NULL) {
crp->Chardata = NewStrBuf();
}
- StrBufAppendBufPlain(crp->Chardata, s, len, 0);
+ StrBufAppendBufPlain(crp->Chardata, app, len, 0);
+
+#ifdef DEBUG_XML_PARSE
+ // logging
+ string_trim(app); // remove leading/trailing whitespace. ok to mangle it because we've already appended.
+ if (!IsEmptyStr(app)) {
+ int i;
+ syslog(LOG_DEBUG, "%s", app, len);
+ }
+ // end logging
+#endif
+ free(app);
return;
}
StrBufXMLEscAppend(ReportOut, Caldata, NULL, 0, 0);
StrBufAppendPrintf(ReportOut, "</C:calendar-data>");
StrBufAppendPrintf(ReportOut, "</D:prop>");
- FreeStrBuf(&Caldata);
- Caldata = NULL;
}
else {
// syslog(LOG_DEBUG, "caldav_report_one_item(%s) 404 not found", ChrPtr(ThisHref));
}
cal_multiget_out(msgnum, ThisHref, Caldata, ReportOut);
+
+ if (Caldata != NULL) {
+ FreeStrBuf(&Caldata);
+ }
+}
+
+
+// Compare function for "time-range" tests (RFC4791 section 9.9)
+// Returns nonzero if the supplied icalcomponent occurs within the specified time range
+//
+// IMPLEMENTATION NOTE:
+// ical_ctdl_is_overlap() works because icaltime_compare() is really smart.
+// It looks at the time zone of the dtstart/dtend and can apparently go back up the icalcomponent
+// hierarchy to find its time zone data. I tested this by creating an event with a fictional
+// time zone and it did the right thing. It even showed the fictional name to me. This saves us
+// from having to convert everything to UTC before comparing. Nice!
+//
+int caldav_time_range_filter_matches(icalcomponent *cal, char *start_str, char *end_str) {
+
+ struct icaltimetype search_start = icaltime_from_string(start_str); // time range being searched
+ struct icaltimetype search_end = icaltime_from_string(end_str);
+
+ struct icaltimetype dtstart = icalcomponent_get_dtstart(cal); // time of event
+ struct icaltimetype dtend = icalcomponent_get_dtend(cal);
+ if (icaltime_is_null_time(dtend)) {
+ dtend = dtstart;
+ }
+
+ // If it is a recurring event, RRULE is available at this level. We can handle it here.
+ icalproperty *rrule = icalcomponent_get_first_property(cal, ICAL_RRULE_PROPERTY);
+ if (rrule) {
+ struct icaldurationtype dur = icaltime_subtract(dtend, dtstart); // recurrences need duration to find dtend
+ struct icalrecurrencetype recur = icalproperty_get_rrule(rrule);
+ icalrecur_iterator *ritr = icalrecur_iterator_new(recur, dtstart); // iterate through recurrences
+ while (dtstart = icalrecur_iterator_next(ritr), !icaltime_is_null_time(dtstart)) {
+ dtend = icaltime_add(dtstart, dur);
+
+ // Does THIS recurrence match the query? If so, free the memory we used and stop iterating.
+ if (ical_ctdl_is_overlap(dtstart, dtend, search_start, search_end)) {
+ icalrecur_iterator_free(ritr);
+ return(1);
+ }
+ }
+
+ icalrecur_iterator_free(ritr);
+ return(0); // compared all recurrences, no match was found for any of them
+ }
+
+ // For non recurring events, do a simple time range compare.
+ return(ical_ctdl_is_overlap(dtstart, dtend, search_start, search_end)); // We have a convenience function for this.
+}
+
+
+// Recursive function to apply CalDAV FILTERS to a calendar item.
+// Returns zero if the calendar item was disqualified by a filter, nonzero if the calendar item still qualifies.
+int caldav_apply_filters(void *cal, Array *filters, int apply_at_level) {
+
+ int f = 0; // filter number iterator
+ int qual = 1; // 0 for disqualify, 1 for qualify
+ int previous_level = -1;
+ int disregard_further_comp_filters = 0;
+
+ while ( (f<array_len(filters)) && (qual) ) {
+
+ // Tokenize the filter (a future performance hack would be to pre-tokenize instead of storing delimited strings)
+ char this_filter[SIZ];
+ safestrncpy(this_filter, array_get_element_at(filters, f), sizeof(this_filter));
+ char *t[10] = { NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL } ;
+ char *ft = this_filter;
+ int num_tokens = 0;
+ while ( (t[num_tokens]=strtok_r(ft, "|", &ft)) && (num_tokens<10) ) {
+ ++num_tokens;
+ }
+ int this_rule_level = atoi(t[0]);
+ syslog(LOG_DEBUG, "caldav_apply_filters() filter=%d, level=%d, <%s>", f, this_rule_level, array_get_element_at(filters, f) );
+
+ // Handle the individual filters defined in RFC4791 9.7.1 through 9.7.5
+
+ if (apply_at_level < previous_level) {
+ syslog(LOG_DEBUG, "caldav: walking back down");
+ return(qual);
+ }
+
+ else if (this_rule_level != apply_at_level) {
+ syslog(LOG_DEBUG, "caldav: apply_at_level=%d, this_rule_level=%d, skipping this rule", apply_at_level, this_rule_level);
+ }
+
+ else if ( (!strcasecmp(t[1], "comp-filter")) // RFC4791 9.7.1 - filter by component
+ && (!disregard_further_comp_filters) // one is enough to succeed
+ ) {
+ syslog(LOG_DEBUG, "component filter at level %d", this_rule_level);
+
+ // comp-filter requires exactly one parameter (name="VXXXX")
+ if (num_tokens < 4) {
+ syslog(LOG_DEBUG, "caldav: comp-filter has no parameters - rejecting");
+ return(0);
+ }
+
+ // Root element is NOT a component, but the root filter is "comp-filter" -- reject!
+ if ( (!icalcomponent_isa_component(cal)) && (this_rule_level == 0) ) {
+ syslog(LOG_DEBUG, "caldav: root element is not a component, rejecting");
+ return(0);
+ }
+
+ // Current element is a component and the filter is "comp-filter" -- see if it matches the requested type
+ if ( (icalcomponent_isa_component(cal))
+ && (!strcasecmp(t[2], "name"))
+ ) {
+ if (icalcomponent_isa(cal) == icalcomponent_string_to_kind(t[3]) ) {
+ syslog(LOG_DEBUG, "caldav: component at level %d is <%s>, looking for <%s>, recursing...",
+ apply_at_level,
+ icalcomponent_kind_to_string(icalcomponent_isa(cal)), t[3]
+ );
+
+ // We have a match. Drill down into the subcomponents.
+
+ icalcomponent *c = NULL;
+ int number_of_subcomponents = 0;
+ int number_of_matches = 0;
+ for ( c = icalcomponent_get_first_component(cal, ICAL_ANY_COMPONENT);
+ (c != 0);
+ c = icalcomponent_get_next_component(cal, ICAL_ANY_COMPONENT)
+ ) {
+ ++number_of_subcomponents;
+ if (caldav_apply_filters(c, filters, apply_at_level+1)) {
+ syslog(LOG_DEBUG, "Subcomponent %d might match", number_of_subcomponents);
+ ++number_of_matches;
+ }
+ }
+ if (number_of_matches > 0) { // something matched
+ qual = 1;
+ disregard_further_comp_filters = 1;
+
+ }
+ else if (number_of_subcomponents > 0) { // nothing matched
+ return(0); // but only fail if there *were* subcomponents.
+ }
+
+ }
+ else {
+ syslog(LOG_DEBUG, "caldav: component at level %d is <%s>, looking for <%s>, rejecting",
+ apply_at_level,
+ icalcomponent_kind_to_string(icalcomponent_isa(cal)),
+ t[3]
+ );
+ return(0);
+ }
+ }
+
+ }
+
+ else if (!strcasecmp(t[1], "prop-filter")) { // RFC4791 9.7.2 - filter by property
+ syslog(LOG_DEBUG, "property filter at level %d FIXME not implemented yet", this_rule_level);
+ }
+
+ else if (!strcasecmp(t[1], "param-filter")) { // RFC4791 9.7.3 - filter by parameter
+ syslog(LOG_DEBUG, "parameter filter at level %d FIXME not implemented yet", this_rule_level);
+ }
+
+ else if (!strcasecmp(t[1], "is-not-defined")) { // RFC4791 9.7.4
+ syslog(LOG_DEBUG, "is-not-defined filter at level %d FIXME not implemented yet", this_rule_level);
+ }
+
+ else if (!strcasecmp(t[1], "text-match")) { // RFC4791 9.7.5
+ syslog(LOG_DEBUG, "text match filter at level %d FIXME not implemented yet", this_rule_level);
+ }
+
+ else if (!strcasecmp(t[1], "time-range")) { // RFC4791 9.9
+ syslog(LOG_DEBUG, "time range filter at level %d", this_rule_level);
+ char *tr_start = (char *)the_beginning_of_time; // default if not specified
+ char *tr_end = (char *)the_end_of_time; // default if not specified
+ for (int i=2; (i+1)<num_tokens; i+=2) {
+ if (!strcasecmp(t[i], "start")) {
+ tr_start = t[i+1];
+ }
+ else if (!strcasecmp(t[i], "end")) {
+ tr_end = t[i+1];
+ }
+ }
+ if (caldav_time_range_filter_matches(cal, tr_start, tr_end)) {
+ syslog(LOG_DEBUG, "time range matches");
+ }
+ else {
+ syslog(LOG_DEBUG, "time range does not match -- rejecting");
+ qual = 0;
+ }
+ }
+
+ ++f;
+ }
+
+ syslog(LOG_DEBUG, "caldav: we reached the end of level %d , returning %d", apply_at_level, qual);
+ return(qual);
}
// is requested on a calendar room. We fire up an XML Parser to decode the request and
// hopefully produce the correct output.
void caldav_report(struct http_transaction *h, struct ctdlsession *c) {
- struct cr_parms crp;
+ struct cr_params crp;
char buf[1024];
- memset(&crp, 0, sizeof(struct cr_parms));
+ memset(&crp, 0, sizeof(struct cr_params));
XML_Parser xp = XML_ParserCreateNS("UTF-8", ':');
if (xp == NULL) {
XML_Parse(xp, h->request_body, h->request_body_length, 1);
XML_ParserFree(xp);
- if (crp.Chardata != NULL) { // Discard any trailing chardata ... normally nothing here
+ if (crp.Chardata != NULL) { // Discard any trailing chardata ... normally nothing here
FreeStrBuf(&crp.Chardata);
crp.Chardata = NULL;
}
long m;
memcpy(&m, array_get_element_at(msglist, i), sizeof(long));
- // Begin -- evaluate the calendar item
-
- syslog(LOG_DEBUG, "evaluating message %ld", m);
- StrBuf *one_item;
- one_item = fetch_ical(c, m);
- syslog(LOG_DEBUG, "calendar item:\n---\n\033[33m%s\n---\033[0m", ChrPtr(one_item));
+ // load and parse one calendar item
+ StrBuf *one_item = fetch_ical(c, m);
+ icalcomponent *cal = icalcomponent_new_from_string(ChrPtr(one_item));
+
+ // Does this calendar item qualify for output? Run this calendar item through the filters.
+ syslog(LOG_DEBUG, "Evaluating message \033[33m%ld\033[0m...", m);
+ if (caldav_apply_filters(cal, crp.filters, 0)) {
+ syslog(LOG_DEBUG, "Message %ld \033[32mQUALIFIES\033[0m", m);
+ // FIXME need to populate the Href instead of NULL
+ cal_multiget_out(m, NULL, one_item, ReportOut);
+ }
+ else {
+ syslog(LOG_DEBUG, "Message %ld \033[31mDOES NOT QUALIFY\033[0m", m);
+ }
+ syslog(LOG_DEBUG, "");
+
+ icalcomponent_free(cal);
FreeStrBuf(&one_item);
- // End - evaluate the calendar item
-
}
array_free(msglist);
}
FreeStrBuf(&crp.Hrefs);
crp.Hrefs = NULL;
}
+ if (crp.filters) {
+ array_free(crp.filters);
+ crp.filters = NULL;
+ }
StrBufAppendPrintf(ReportOut, "</D:multistatus>\n"); // End the REPORT.