WARNING NOT Y10K COMPLIANT
[citadel.git] / webcit-ng / server / caldav_reports.c
index dbaa9c5971ed2430fc9340ed57ae693b11ecac6e..bd451e9e2d5e0821abe75ae54d81630d03f5d238 100644 (file)
@@ -1,13 +1,11 @@
-// This file contains functions which handle all of the CalDAV "REPORT" queries
-// specified in RFC4791 section 7.
-//
-// Copyright (c) 2023 by the citadel.org team
-//
-// This program is open source software.  Use, duplication, or
-// disclosure are subject to the GNU General Public License v3.
+// 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.
 
 #include "webcit.h"
 
+#define CAL "urn:ietf:params:xml:ns:caldav:"           // Shorthand for the XML namespace of CalDAV
+#define CALLEN sizeof(CAL)-1                           // And the length of that string
 
 // A CalDAV REPORT can only be one type.  This is stored in the report_type member.
 enum cr_type {
@@ -20,50 +18,93 @@ enum cr_type {
 // 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
+       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);
+#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
 
-       for (i = 0; attr[i] != NULL; i += 2) {
-               syslog(LOG_DEBUG, "                    Attribute '%s' = '%s'", attr[i], attr[i + 1]);
+       // RFC4791 7.8 "calendar-query" REPORT - Client will send a lot of search criteria.
+       if (!strcasecmp(el, CAL"calendar-query")) {
+               crp->report_type = cr_calendar_query;
        }
 
-       if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-multiget")) {
+       // RFC4791 7.9 "calendar-multiget" REPORT - Client will supply a list of specific hrefs.
+       else if (!strcasecmp(el, CAL"calendar-multiget")) {
                crp->report_type = cr_calendar_multiget;
        }
 
-       else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:calendar-query")) {
-               crp->report_type = cr_calendar_query;
+       // RFC4791 7.10 "free-busy-query" REPORT
+       else if (!strcasecmp(el, CAL"free-busy-query")) {
+               crp->report_type = cr_freebusy_query;
        }
 
-       else if (!strcasecmp(el, "urn:ietf:params:xml:ns:caldav:free-busy-query")) {
-               crp->report_type = cr_freebusy_query;
+       // RFC4791 9.7 create a filter array if this query contains a "filter" stanza
+       else if (!strcasecmp(el, CAL"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, CAL"comp-filter"))
+                               || (!strcasecmp(el, CAL"prop-filter"))
+                               || (!strcasecmp(el, CAL"param-filter"))
+                               || (!strcasecmp(el, CAL"is-not-defined"))
+                               || (!strcasecmp(el, CAL"text-match"))
+                               || (!strcasecmp(el, CAL"time-range"))
+                       )
+                       && (crp->filters)                       // Make sure we actually allocated an array
+       ) {
+
+               if (!strcasecmp(el, CAL"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[CALLEN]);           // 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);
        }
 
-       ++crp->tag_nesting_level;
 }
 
 
 // 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, CAL"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
@@ -83,25 +124,43 @@ void caldav_xml_end(void *data, const char *el) {
 
 
 // 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;
 }
 
 
-// Called by caldav_response() to fetch a message (by number) in the current room,
+// Called by caldav_report_one_item() to fetch a message (by number) in the current room,
 // and return only the icalendar data as a StrBuf.  Returns NULL if not found.
 //
 // NOTE: this function expects that "MSGP text/calendar" was issued at the beginning
 // of a REPORT operation to set our preferred MIME type to calendar data.
-StrBuf *fetch_ical(struct ctdlsession * c, long msgnum) {
+StrBuf *fetch_ical(struct ctdlsession *c, long msgnum) {
        char buf[1024];
        StrBuf *Buf = NULL;
 
@@ -112,7 +171,7 @@ StrBuf *fetch_ical(struct ctdlsession * c, long msgnum) {
        }
 
        while (ctdl_readline(c, buf, sizeof(buf)), strcmp(buf, "000")) {
-               if (Buf != NULL) {      // already in body
+               if (Buf != NULL) {              // already in body
                        StrBufAppendPrintf(Buf, "%s\n", buf);
                }
                else if (IsEmptyStr(buf)) {     // beginning of body
@@ -121,31 +180,48 @@ StrBuf *fetch_ical(struct ctdlsession * c, long msgnum) {
        }
 
        return Buf;
+}
+
+
+// Called by multiple REPORT types to actually perform the output in "multiget" format.
+// We need to already know the source message number and the href, but also already have the output data.
+void cal_multiget_out(long msgnum, StrBuf *ThisHref, StrBuf *Caldata, StrBuf *ReportOut) {
+
+       StrBufAppendPrintf(ReportOut, "<D:response>");
+       StrBufAppendPrintf(ReportOut, "<D:href>");
+       StrBufXMLEscAppend(ReportOut, ThisHref, NULL, 0, 0);
+       StrBufAppendPrintf(ReportOut, "</D:href>");
+       StrBufAppendPrintf(ReportOut, "<D:propstat>");
+
+       if (Caldata != NULL) {
+               // syslog(LOG_DEBUG, "caldav_report_one_item(%s) 200 OK", ChrPtr(ThisHref));
+               StrBufAppendPrintf(ReportOut, "<D:status>");
+               StrBufAppendPrintf(ReportOut, "HTTP/1.1 200 OK");
+               StrBufAppendPrintf(ReportOut, "</D:status>");
+               StrBufAppendPrintf(ReportOut, "<D:prop>");
+               StrBufAppendPrintf(ReportOut, "<D:getetag>");
+               StrBufAppendPrintf(ReportOut, "%ld", msgnum);
+               StrBufAppendPrintf(ReportOut, "</D:getetag>");
+               StrBufAppendPrintf(ReportOut, "<C:calendar-data>");
+               StrBufXMLEscAppend(ReportOut, Caldata, NULL, 0, 0);
+               StrBufAppendPrintf(ReportOut, "</C:calendar-data>");
+               StrBufAppendPrintf(ReportOut, "</D:prop>");
+       }
+       else {
+               // syslog(LOG_DEBUG, "caldav_report_one_item(%s) 404 not found", ChrPtr(ThisHref));
+               StrBufAppendPrintf(ReportOut, "<D:status>");
+               StrBufAppendPrintf(ReportOut, "HTTP/1.1 404 not found");
+               StrBufAppendPrintf(ReportOut, "</D:status>");
+       }
 
-// webcit[13039]: msgn=53CE87AF-00392161@uncensored.citadel.org
-// webcit[13039]: path=IGnatius T Foobar
-// webcit[13039]: time=1208008800
-// webcit[13039]: from=IGnatius T Foobar
-// webcit[13039]: room=0000000001.Calendar
-// webcit[13039]: node=uncnsrd
-// webcit[13039]: hnod=Uncensored
-// webcit[13039]: exti=040000E00074C5B7101A82E0080000000080C728F83E84C801000000000000000010000000E857E0DC57F53947ADF0BB91EE3A502F
-// webcit[13039]: subj==?UTF-8?B?V2VzbGV5J3MgYmlydGhkYXkgcGFydHk=
-// webcit[13039]: ?=
-// webcit[13039]: part=||1||text/calendar|1127||
-// webcit[13039]: text
-// webcit[13039]: Content-type: text/calendar
-// webcit[13039]: Content-length: 1127
-// webcit[13039]: Content-transfer-encoding: 7bit
-// webcit[13039]: X-Citadel-MSG4-Partnum: 1
-// webcit[13039]:
-// webcit[13039]: BEGIN:VCALENDAR
+       StrBufAppendPrintf(ReportOut, "</D:propstat>");
+       StrBufAppendPrintf(ReportOut, "</D:response>");
 }
 
 
 // Called by caldav_report() to output a single item.
 // Our policy is to throw away the list of properties the client asked for, and just send everything.
-void caldav_response(struct http_transaction *h, struct ctdlsession *c, StrBuf * ReportOut, StrBuf * ThisHref) {
+void caldav_report_one_item(struct http_transaction *h, struct ctdlsession *c, StrBuf *ReportOut, StrBuf *ThisHref) {
        long msgnum;
        StrBuf *Caldata = NULL;
        char *euid;
@@ -164,43 +240,216 @@ void caldav_response(struct http_transaction *h, struct ctdlsession *c, StrBuf *
        }
        unescape_input(unescaped_euid);
 
-       StrBufAppendPrintf(ReportOut, "<D:response>");
-       StrBufAppendPrintf(ReportOut, "<D:href>");
-       StrBufXMLEscAppend(ReportOut, ThisHref, NULL, 0, 0);
-       StrBufAppendPrintf(ReportOut, "</D:href>");
-       StrBufAppendPrintf(ReportOut, "<D:propstat>");
-
        msgnum = locate_message_by_uid(c, unescaped_euid);
        free(unescaped_euid);
        if (msgnum > 0) {
                Caldata = fetch_ical(c, msgnum);
        }
+       else {
+               Caldata = NULL;
+       }
+
+       cal_multiget_out(msgnum, ThisHref, Caldata, ReportOut);
 
        if (Caldata != NULL) {
-               // syslog(LOG_DEBUG, "caldav_response(%s) 200 OK", ChrPtr(ThisHref));
-               StrBufAppendPrintf(ReportOut, "<D:status>");
-               StrBufAppendPrintf(ReportOut, "HTTP/1.1 200 OK");
-               StrBufAppendPrintf(ReportOut, "</D:status>");
-               StrBufAppendPrintf(ReportOut, "<D:prop>");
-               StrBufAppendPrintf(ReportOut, "<D:getetag>");
-               StrBufAppendPrintf(ReportOut, "%ld", msgnum);
-               StrBufAppendPrintf(ReportOut, "</D:getetag>");
-               StrBufAppendPrintf(ReportOut, "<C:calendar-data>");
-               StrBufXMLEscAppend(ReportOut, Caldata, NULL, 0, 0);
-               StrBufAppendPrintf(ReportOut, "</C:calendar-data>");
-               StrBufAppendPrintf(ReportOut, "</D:prop>");
                FreeStrBuf(&Caldata);
-               Caldata = NULL;
        }
-       else {
-               // syslog(LOG_DEBUG, "caldav_response(%s) 404 not found", ChrPtr(ThisHref));
-               StrBufAppendPrintf(ReportOut, "<D:status>");
-               StrBufAppendPrintf(ReportOut, "HTTP/1.1 404 not found");
-               StrBufAppendPrintf(ReportOut, "</D:status>");
+}
+
+
+// Compare function for "time-range" tests (RFC4791 section 9.9)
+// Returns nonzero if the supplied icalcomponent occurs within the specified time range
+int caldav_time_range_filter_matches(icalcomponent *cal_in, char *start_str, char *end_str) {
+
+       struct icaltimetype start = (
+               start_str
+               ? icaltime_from_string(start_str)
+               : icaltime_from_string("19010101T010101Z")
+       );
+
+       struct icaltimetype end = (
+               end_str
+               ? icaltime_from_string(end_str)
+               : icaltime_from_string("99991231T235959Z")              // ISO8601 is not Y10K compliant
+       );
+
+
+// NOTE TO ME: The header file says
+// "This converts both times to the UTC timezone and compares them."
+//     LIBICAL_ICAL_EXPORT int icaltime_compare(const struct icaltimetype a, const struct icaltimetype b);
+// How does it do that without knowing the time zone?  Does it use a private method to look up into the
+// parent component to find a VTIMEZONE component?  Find out.  If it can do that, we don't have to dezonify.
+
+
+
+
+
+       // make a local copy of the component because we are going to modify it by converting times to UTC
+       icalcomponent *cal = icalcomponent_new_clone(cal_in);
+       ical_dezonify(cal);
+
+       syslog(LOG_DEBUG, "\033[7mcaldav_time_range_filter_matches()\033[0m : Does this %s fall between %s and %s ?",
+               icalcomponent_kind_to_string(icalcomponent_isa(cal)),
+               start_str,
+               end_str
+       );
+
+       syslog(LOG_DEBUG, "Well, here it is:");
+       syslog(LOG_DEBUG, "\033[35m%s\033[0m", icalcomponent_as_ical_string_r(cal));
+
+       icaltimetype dts = icalcomponent_get_dtstart(cal);
+       syslog(LOG_DEBUG, "component start: \033[36m%s\033[0m", icaltime_as_ical_string_r(dts));
+
+       icaltimetype dte = icalcomponent_get_dtend(cal);
+       syslog(LOG_DEBUG, "component   end: \033[36m%s\033[0m", icaltime_as_ical_string_r(dte));
+
+       int result = ical_ctdl_is_overlap(dts, dte, start, end);        // We have a convenience function for this.
+
+       icalcomponent_free(cal);
+       return(result);
+}
+
+
+// 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 FIXME not implemented yet", this_rule_level);
+                       for (int i=2; (i+1)<num_tokens; i+=2) {
+                               char *tr_start = NULL;
+                               char *tr_end = NULL;
+                               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;
        }
 
-       StrBufAppendPrintf(ReportOut, "</D:propstat>");
-       StrBufAppendPrintf(ReportOut, "</D:response>");
+       syslog(LOG_DEBUG, "caldav: we reached the end of level %d , returning %d", apply_at_level, qual);
+       return(qual);
 }
 
 
@@ -208,10 +457,10 @@ void caldav_response(struct http_transaction *h, struct ctdlsession *c, StrBuf *
 // 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) {
@@ -227,7 +476,7 @@ void caldav_report(struct http_transaction *h, struct ctdlsession *c) {
        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;
        }
@@ -248,18 +497,71 @@ void caldav_report(struct http_transaction *h, struct ctdlsession *c) {
                ">"
        );
 
-       if (crp.Hrefs != NULL) {        // Output all qualifying calendar items!
+       // RFC4791 7.8 "calendar-query" REPORT - Client will send a lot of search criteria.
+       if (crp.report_type == cr_calendar_query) {
+               int i = 0;
+               Array *msglist = get_msglist(c, "ALL");
+               if (msglist != NULL) {
+                       for (i = 0; i < array_len(msglist); ++i) {
+                               long m;
+                               memcpy(&m, array_get_element_at(msglist, i), sizeof(long));
+
+                               // 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?
+                               int qualify = 1;
+
+                               // If there was a filter stanza, run this calendar item through the filters.
+                               syslog(LOG_DEBUG, "Evaluating message \033[33m%ld\033[0m...", m);
+                               qualify = caldav_apply_filters(cal, crp.filters, 0);
+                               syslog(LOG_DEBUG, "Message %ld %s\033[0m qualify", m, (qualify ? "\033[32mDOES" : "\033[31mDOES NOT"));
+                               syslog(LOG_DEBUG, "");
+
+                               // Did this calendar item match the query?  If so, output it.
+                               if (qualify) {
+                                       // FIXME need to populate the Href instead of NULL
+                                       cal_multiget_out(m, NULL, one_item, ReportOut);
+                               }
+
+                               icalcomponent_free(cal);
+                               FreeStrBuf(&one_item);
+
+                       }
+                       array_free(msglist);
+               }
+       }
+
+       // RFC4791 7.9 "calendar-multiget" REPORT - go get the specific Hrefs the client asked for.
+       // Can we move this back into citserver too?
+       else if ( (crp.report_type == cr_calendar_multiget) && (crp.Hrefs != NULL) ) {
+
                StrBuf *ThisHref = NewStrBuf();
                const char *pvset = NULL;
                while (StrBufExtract_NextToken(ThisHref, crp.Hrefs, &pvset, '|') >= 0) {
-                       caldav_response(h, c, ReportOut, ThisHref);
+                       StrBufTrim(ThisHref);                           // remove leading/trailing whitespace from the href
+                       caldav_report_one_item(h, c, ReportOut, ThisHref);
                }
                FreeStrBuf(&ThisHref);
+       }
+
+       // RFC4791 7.10 "free-busy-query" REPORT
+       else if (crp.report_type == cr_freebusy_query) {
+               // FIXME build this REPORT.  At the moment we send an empty multistatus.
+       }
+
+       // Free any query parameters that might have been allocated during the xml parse
+       if (crp.Hrefs != NULL) {
                FreeStrBuf(&crp.Hrefs);
                crp.Hrefs = NULL;
        }
+       if (crp.filters) {
+               array_free(crp.filters);
+               crp.filters = NULL;
+       }
 
-       StrBufAppendPrintf(ReportOut, "</D:multistatus>\n");    // End the REPORT.
+       StrBufAppendPrintf(ReportOut, "</D:multistatus>\n");            // End the REPORT.
 
        add_response_header(h, strdup("Content-type"), strdup("text/xml"));
        h->response_code = 207;