config: add rfc1912 dateserial policy

close #582

.gitignore

@@ -79,3 +79,8 @@ version.h
 
 # Vagrant
 .vagrant
+
+# eclipse
+/.project
+/.cproject
+/.settings/

NEWS

@@ -1,3 +1,11 @@
+Knot DNS 2.7.0 (2018-xx-xx)
+===========================
+
+Features:
+---------
+ - New zone serial policy DATESERIAL: yyyyMMDDvv (Thanks to Wolfgang Jung)
+
+
 Knot DNS 2.6.0 (2017-09-29)
 ===========================
 

doc/man/knot.conf.5in

@@ -983,7 +983,7 @@ zone:
     dnssec\-signing: BOOL
     dnssec\-policy: STR
     request\-edns\-option: INT:[HEXSTR]
-    serial\-policy: increment | unixtime
+    serial\-policy: increment | unixtime | dateserial
     min\-refresh\-interval: TIME
     max\-refresh\-interval: TIME
     module: STR/STR ...
@@ -1219,6 +1219,12 @@ Possible values:
 \fBincrement\fP – The serial is incremented according to serial number arithmetic
 .IP \(bu 2
 \fBunixtime\fP – The serial is set to the current unix time
+.IP \(bu 2
+.INDENT 2.0
+.TP
+\fBdateserial\fP – The 10\-digit serial (YYYYMMDDnn) is incremented, the first
+8 digits match the current iso\-date
+.UNINDENT
 .UNINDENT
 .sp
 \fBNOTE:\fP
@@ -1228,6 +1234,8 @@ If your serial was in other than unix time format, be careful
 with the transition to unix time.  It may happen that the new serial will
 be \(aqlower\(aq than the old one. If this is the case, the transition should be
 done by hand (\fI\%RFC 1982\fP).
+.sp
+Use dateserial only if you expect less than 100 updates per day per zone.
 .UNINDENT
 .UNINDENT
 .sp

doc/reference.rst

@@ -1110,7 +1110,7 @@ Definition of zones served by the server.
      dnssec-signing: BOOL
      dnssec-policy: STR
      request-edns-option: INT:[HEXSTR]
-     serial-policy: increment | unixtime
+     serial-policy: increment | unixtime | dateserial
      min-refresh-interval: TIME
      max-refresh-interval: TIME
      module: STR/STR ...
@@ -1382,6 +1382,8 @@ Possible values:
 
 - ``increment`` – The serial is incremented according to serial number arithmetic
 - ``unixtime`` – The serial is set to the current unix time
+- ``dateserial`` – The 10-digit serial (YYYYMMDDnn) is incremented, the first
+                   8 digits match the current iso-date
 
 .. NOTE::
    If your serial was in other than unix time format, be careful
@@ -1389,6 +1391,8 @@ Possible values:
    be \'lower\' than the old one. If this is the case, the transition should be
    done by hand (:rfc:`1982`).
 
+   Use dateserial only if you expect less than 100 updates per day per zone.
+
 *Default:* increment
 
 .. _zone_min-refresh-interval:

src/knot/conf/schema.c

@@ -87,8 +87,9 @@ const knot_lookup_t acl_actions[] = {
 };
 
 static const knot_lookup_t serial_policies[] = {
-	{ SERIAL_POLICY_INCREMENT, "increment" },
-	{ SERIAL_POLICY_UNIXTIME,  "unixtime" },
+	{ SERIAL_POLICY_INCREMENT,  "increment" },
+	{ SERIAL_POLICY_UNIXTIME,   "unixtime" },
+	{ SERIAL_POLICY_DATESERIAL, "dateserial" },
 	{ 0, NULL }
 };
 

src/knot/conf/schema.h

@@ -129,8 +129,9 @@ enum {
 };
 
 enum {
-	SERIAL_POLICY_INCREMENT = 1,
-	SERIAL_POLICY_UNIXTIME  = 2,
+	SERIAL_POLICY_INCREMENT  = 1,
+	SERIAL_POLICY_UNIXTIME   = 2,
+	SERIAL_POLICY_DATESERIAL = 3,
 };
 
 enum {

src/knot/zone/serial.c

@@ -35,6 +35,28 @@ serial_cmp_result_t serial_compare(uint32_t s1, uint32_t s2)
 	return diffbrief2result[diffbrief];
 }
 
+static uint32_t serial_next_date(uint32_t current)
+{
+	uint32_t next = current + 1;
+
+	struct tm now;
+	time_t current_time = time(NULL);
+	struct tm *gmtime_result = gmtime_r(&current_time, &now);
+	if (gmtime_result == NULL) {
+		return next;
+	}
+
+	uint32_t yyyyMMdd00 = (1900 + now.tm_year) * 1000000 +
+	                      (   1 + now.tm_mon ) *   10000 +
+	                      (       now.tm_mday) *     100;
+
+	if (next < yyyyMMdd00) {
+		next = yyyyMMdd00;
+	}
+
+	return next;
+}
+
 uint32_t serial_next(uint32_t current, int policy)
 {
 	switch (policy) {
@@ -42,6 +64,8 @@ uint32_t serial_next(uint32_t current, int policy)
 		return current + 1;
 	case SERIAL_POLICY_UNIXTIME:
 		return time(NULL);
+	case SERIAL_POLICY_DATESERIAL:
+		return serial_next_date(current);
 	default:
 		assert(0);
 		return 0;

src/knot/zone/serial.h

@@ -47,7 +47,8 @@ inline static bool serial_equal(uint32_t a, uint32_t b)
  * \brief Get next serial for given serial update policy.
  *
  * \param current  Current SOA serial.
- * \param policy   SERIAL_POLICY_INCREMENT or SERIAL_POLICY_UNIXTIME.
+ * \param policy   SERIAL_POLICY_INCREMENT, SERIAL_POLICY_UNIXTIME or
+ *                 SERIAL_POLICY_DATESERIAL.
  *
  * \return New serial.
  */

tests/knot/test_zone_serial.c

@@ -1,4 +1,4 @@
-/*  Copyright (C) 2015 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+/*  Copyright (C) 2018 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
 
     This program is free software: you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
@@ -14,10 +14,14 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+#include <assert.h>
 #include <tap/basic.h>
 #include <stdlib.h>
+#include <time.h>
 
 #include "knot/zone/serial.h"
+#include "knot/conf/schema.h"
+#include "contrib/strtonum.h"
 
 enum serials {
 	S_LOWEST = 0,			// lowest value
@@ -38,9 +42,36 @@ static uint32_t random_serial(void)
 	return s;
 }
 
+static void check_dateserial(uint32_t current, uint32_t expected, const char *msg)
+{
+	uint32_t next = serial_next(current, SERIAL_POLICY_DATESERIAL);
+	ok(next == expected, "dateserial: %s", msg);
+}
+
+static void test_dateserial(void)
+{
+	time_t now = time(NULL);
+
+	struct tm *gm_ret = gmtime(&now);
+	assert(gm_ret);
+
+	char str[32];
+	int ret = strftime(str, sizeof(str), "%Y%m%d00", gm_ret);
+	assert(ret > 0);
+
+	uint32_t serial0;
+	ret = str_to_u32(str, &serial0);
+	assert(ret == KNOT_EOK);
+
+	check_dateserial(2000010100, serial0, "from old date");
+	check_dateserial(serial0, serial0 + 1, "today's first increment");
+	check_dateserial(serial0 + 98, serial0 + 99, "today's last increment");
+	check_dateserial(2100010100, 2100010101, "from future date");
+}
+
 int main(int argc, char *argv[])
 {
-	plan(20);
+	plan_lazy();
 
 	/* Serial compare test. */
 	ok(serial_compare(S_LOWEST, S_BELOW_MIDDLE) == SERIAL_LOWER,
@@ -98,5 +129,7 @@ int main(int argc, char *argv[])
 	ok(serial_compare(s2, s1) == SERIAL_INCOMPARABLE,
 	   "serial compare: random opposites (s2 < s1)");
 
+	test_dateserial();
+
 	return 0;
 }