The "time" simple database driver.

contrib/sdb/time/timedb.c

@@ -0,0 +1,121 @@
+#include <config.h>
+
+#include <string.h>
+#include <stdio.h>
+#include <time.h>
+
+#include <isc/print.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+#include <dns/sdb.h>
+
+#include <named/globals.h>
+
+/*
+ * A simple database driver that enables the server to return the
+ * current time in a DNS record.
+ */
+
+static dns_sdbimplementation_t *timedb = NULL;
+
+/*
+ * This database operates on relative names.
+ *
+ * "time" and "@" return the time in a TXT record.  
+ * "clock" is a CNAME to "time"
+ * "current" is a DNAME to "@" (try time.current.time)
+ */ 
+static isc_result_t
+timedb_lookup(const char *zone, const char *name, void *dbdata,
+	      dns_sdblookup_t *lookup)
+{
+	isc_result_t result;
+
+	UNUSED(zone);
+	UNUSED(dbdata);
+
+	if (strcmp(name, "@") == 0 || strcmp(name, "time") == 0) {
+		time_t now = time(NULL);
+		char buf[100];
+		int n;
+
+		/*
+		 * Call ctime to create the string, put it in quotes, and
+		 * remove the trailing newline.
+		 */
+		n = snprintf(buf, sizeof(buf), "\"%s", ctime(&now));
+		if (n < 0)
+			return (ISC_R_FAILURE);
+		buf[n - 1] = '\"';
+		result = dns_sdb_putrr(lookup, "txt", 1, buf);
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else if (strcmp(name, "clock") == 0) {
+		result = dns_sdb_putrr(lookup, "cname", 1, "time");
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else if (strcmp(name, "current") == 0) {
+		result = dns_sdb_putrr(lookup, "dname", 1, "@");
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else
+		return (ISC_R_NOTFOUND);
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * lookup() does not return SOA or NS records, so authority() must be defined.
+ */
+static isc_result_t
+timedb_authority(const char *zone, void *dbdata, dns_sdblookup_t *lookup) {
+	isc_result_t result;
+
+	UNUSED(zone);
+	UNUSED(dbdata);
+
+	result = dns_sdb_putsoa(lookup, "localhost.", "root.localhost.", 0);
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+
+	result = dns_sdb_putrr(lookup, "ns", 86400, "ns1.localdomain.");
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+	result = dns_sdb_putrr(lookup, "ns", 86400, "ns2.localdomain.");
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * This zone does not support zone transfer, so allnodes() is NULL.  There
+ * is no driver specific data, so create() and destroy() are NULL.
+ */
+static dns_sdbmethods_t timedb_methods = {
+	timedb_lookup,
+	timedb_authority,
+	NULL,	/* allnodes */
+	NULL,	/* create */
+	NULL	/* destroy */
+};
+
+/*
+ * Wrapper around dns_sdb_register().
+ */
+isc_result_t
+timedb_init(void) {
+	unsigned int flags;
+	flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA;
+	return (dns_sdb_register("time", &timedb_methods, NULL, flags,
+				 ns_g_mctx, &timedb));
+}
+
+/*
+ * Wrapper around dns_sdb_unregister().
+ */
+void
+timedb_clear(void) {
+	dns_sdb_unregister(&timedb);
+}

contrib/sdb/timedb.c

@@ -0,0 +1,121 @@
+#include <config.h>
+
+#include <string.h>
+#include <stdio.h>
+#include <time.h>
+
+#include <isc/print.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+#include <dns/sdb.h>
+
+#include <named/globals.h>
+
+/*
+ * A simple database driver that enables the server to return the
+ * current time in a DNS record.
+ */
+
+static dns_sdbimplementation_t *timedb = NULL;
+
+/*
+ * This database operates on relative names.
+ *
+ * "time" and "@" return the time in a TXT record.  
+ * "clock" is a CNAME to "time"
+ * "current" is a DNAME to "@" (try time.current.time)
+ */ 
+static isc_result_t
+timedb_lookup(const char *zone, const char *name, void *dbdata,
+	      dns_sdblookup_t *lookup)
+{
+	isc_result_t result;
+
+	UNUSED(zone);
+	UNUSED(dbdata);
+
+	if (strcmp(name, "@") == 0 || strcmp(name, "time") == 0) {
+		time_t now = time(NULL);
+		char buf[100];
+		int n;
+
+		/*
+		 * Call ctime to create the string, put it in quotes, and
+		 * remove the trailing newline.
+		 */
+		n = snprintf(buf, sizeof(buf), "\"%s", ctime(&now));
+		if (n < 0)
+			return (ISC_R_FAILURE);
+		buf[n - 1] = '\"';
+		result = dns_sdb_putrr(lookup, "txt", 1, buf);
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else if (strcmp(name, "clock") == 0) {
+		result = dns_sdb_putrr(lookup, "cname", 1, "time");
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else if (strcmp(name, "current") == 0) {
+		result = dns_sdb_putrr(lookup, "dname", 1, "@");
+		if (result != ISC_R_SUCCESS)
+			return (ISC_R_FAILURE);
+	} else
+		return (ISC_R_NOTFOUND);
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * lookup() does not return SOA or NS records, so authority() must be defined.
+ */
+static isc_result_t
+timedb_authority(const char *zone, void *dbdata, dns_sdblookup_t *lookup) {
+	isc_result_t result;
+
+	UNUSED(zone);
+	UNUSED(dbdata);
+
+	result = dns_sdb_putsoa(lookup, "localhost.", "root.localhost.", 0);
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+
+	result = dns_sdb_putrr(lookup, "ns", 86400, "ns1.localdomain.");
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+	result = dns_sdb_putrr(lookup, "ns", 86400, "ns2.localdomain.");
+	if (result != ISC_R_SUCCESS)
+		return (ISC_R_FAILURE);
+
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * This zone does not support zone transfer, so allnodes() is NULL.  There
+ * is no driver specific data, so create() and destroy() are NULL.
+ */
+static dns_sdbmethods_t timedb_methods = {
+	timedb_lookup,
+	timedb_authority,
+	NULL,	/* allnodes */
+	NULL,	/* create */
+	NULL	/* destroy */
+};
+
+/*
+ * Wrapper around dns_sdb_register().
+ */
+isc_result_t
+timedb_init(void) {
+	unsigned int flags;
+	flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA;
+	return (dns_sdb_register("time", &timedb_methods, NULL, flags,
+				 ns_g_mctx, &timedb));
+}
+
+/*
+ * Wrapper around dns_sdb_unregister().
+ */
+void
+timedb_clear(void) {
+	dns_sdb_unregister(&timedb);
+}