From e4e2e0eb20794972b8d4c89dcfeb6c257c45c3a1 Mon Sep 17 00:00:00 2001
From: Lukas Fleischer <lfleischer@calcurse.org>
Date: Tue, 7 Feb 2017 17:52:14 +0100
Subject: Gracefully parse iCal parameters with colons
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According to RFC 5545, iCalendar content lines can have optional
parameters, which can be quoted strings containing colons (":"). Make
sure that such colons are not interpreted as delimiters marking the
start of the value string.
Also, add a test case that covers this corner case.
Reported-by: Håkan Jerning <jerning@home.se>
Signed-off-by: Lukas Fleischer <lfleischer@calcurse.org>
---
src/ical.c | 36 ++++++++++++++++++++++++------------
1 file changed, 24 insertions(+), 12 deletions(-)
(limited to 'src')
diff --git a/src/ical.c b/src/ical.c
index f17b1cf..c2c8c5b 100644
--- a/src/ical.c
+++ b/src/ical.c
@@ -670,6 +670,21 @@ static long ical_compute_rpt_until(long start, ical_rpt_t * rpt)
}
}
+/*
+ * Skip to the value part of an iCalendar content line.
+ */
+static char *ical_get_value(char *p)
+{
+ for (; *p != ':'; p++) {
+ if (*p == '\0')
+ return NULL;
+ if (*p == '"')
+ for (p++; *p != '"'; p++);
+ }
+
+ return p + 1;
+}
+
/*
* Read a recurrence rule from an iCalendar RRULE string.
*
@@ -717,14 +732,13 @@ static ical_rpt_t *ical_read_rrule(FILE * log, char *rrulestr,
ical_rpt_t *rpt;
char *p;
- p = strchr(rrulestr, ':');
+ p = ical_get_value(rrulestr);
if (!p) {
ical_log(log, ICAL_VEVENT, itemline,
_("recurrence rule malformed."));
(*noskipped)++;
return NULL;
}
- p++;
rpt = mem_malloc(sizeof(ical_rpt_t));
memset(rpt, 0, sizeof(ical_rpt_t));
@@ -807,14 +821,13 @@ ical_read_exdate(llist_t * exc, FILE * log, char *exstr,
{
char *p, *q;
- p = strchr(exstr, ':');
+ p = ical_get_value(exstr);
if (!p) {
ical_log(log, ICAL_VEVENT, itemline,
_("recurrence exception dates malformed."));
(*noskipped)++;
return;
}
- p++;
while ((q = strchr(p, ',')) != NULL) {
char buf[BUFSIZ];
@@ -835,14 +848,13 @@ static char *ical_read_note(char *line, unsigned *noskipped,
{
char *p, *notestr, *note;
- p = strchr(line, ':');
+ p = ical_get_value(line);
if (!p) {
ical_log(log, item_type, itemline,
_("description malformed."));
(*noskipped)++;
return NULL;
}
- p++;
notestr = ical_unformat_line(p);
if (notestr == NULL) {
@@ -865,11 +877,11 @@ static char *ical_read_summary(char *line)
{
char *p, *summary;
- p = strchr(line, ':');
+ p = ical_get_value(line);
if (!p)
return NULL;
- summary = ical_unformat_line(p + 1);
+ summary = ical_unformat_line(p);
if (!summary)
return NULL;
@@ -970,28 +982,28 @@ ical_read_event(FILE * fdi, FILE * log, unsigned *noevents,
}
if (starts_with_ci(buf, "DTSTART")) {
- p = strchr(buf, ':');
+ p = ical_get_value(buf);
if (!p) {
ical_log(log, ICAL_VEVENT, ITEMLINE,
_("event start time malformed."));
goto cleanup;
}
- vevent.start = ical_datetime2time_t(++p, &vevent_type);
+ vevent.start = ical_datetime2time_t(p, &vevent_type);
if (!vevent.start) {
ical_log(log, ICAL_VEVENT, ITEMLINE,
_("could not retrieve event start time."));
goto cleanup;
}
} else if (starts_with_ci(buf, "DTEND")) {
- p = strchr(buf, ':');
+ p = ical_get_value(buf);
if (!p) {
ical_log(log, ICAL_VEVENT, ITEMLINE,
_("event end time malformed."));
goto cleanup;
}
- vevent.end = ical_datetime2time_t(++p, &vevent_type);
+ vevent.end = ical_datetime2time_t(p, &vevent_type);
if (!vevent.end) {
ical_log(log, ICAL_VEVENT, ITEMLINE,
_("could not retrieve event end time."));
--
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