added sample sdb driver where the zone data is specified

algorithmically in Tcl code

contrib/sdb/lookup.tcl

@@ -0,0 +1,17 @@
+#
+# Sample lookup procedure for tcldb
+#
+
+proc lookup {zone name} {
+    global dbargs
+    puts $zone
+    switch -- $name {
+	@ { return [list \
+		{SOA 86400 "ns.isp.nil. hostmaster.isp.nil. 0 3600 1800 1814400 3600"} \
+		{NS 86400 "ns1"} \
+		{NS 86400 "ns2"} \
+		{MX 86400 "10 mail.isp.nil."} ] }
+	www { return [list [list A 3600 $dbargs($zone)] ] }
+    }
+    return NXDOMAIN
+}

contrib/sdb/tcl/lookup.tcl

@@ -0,0 +1,17 @@
+#
+# Sample lookup procedure for tcldb
+#
+
+proc lookup {zone name} {
+    global dbargs
+    puts $zone
+    switch -- $name {
+	@ { return [list \
+		{SOA 86400 "ns.isp.nil. hostmaster.isp.nil. 0 3600 1800 1814400 3600"} \
+		{NS 86400 "ns1"} \
+		{NS 86400 "ns2"} \
+		{MX 86400 "10 mail.isp.nil."} ] }
+	www { return [list [list A 3600 $dbargs($zone)] ] }
+    }
+    return NXDOMAIN
+}

contrib/sdb/tcl/tcldb.c

@@ -0,0 +1,201 @@
+#include <config.h>
+
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include <isc/mem.h>
+#include <isc/print.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+#include <dns/log.h>
+#include <dns/sdb.h>
+
+#include <named/globals.h>
+
+#include <tcl.h>
+
+#include <tcldb.h>
+
+/*
+ * A simple database driver that calls Tcl procedures to define
+ * the contents of the DNS namespace.
+ */
+
+static dns_sdbimplementation_t *tcldb = NULL;
+
+#define CHECK(op)						\
+	do { result = (op);					\
+		if (result != ISC_R_SUCCESS) return (result);	\
+	} while (0)
+
+typedef struct tcldb_driver {
+	isc_mem_t *mctx;
+	Tcl_Interp *interp;
+} tcldb_driver_t;
+
+static tcldb_driver_t *the_driver;
+
+static isc_result_t
+tcldb_driver_create(isc_mem_t *mctx, tcldb_driver_t **driverp) {
+	int tclres;
+	tcldb_driver_t *driver = isc_mem_get(mctx, sizeof(tcldb_driver_t));
+	if (driver == NULL)
+		return (ISC_R_NOMEMORY);
+	driver->mctx = mctx;
+	driver->interp = Tcl_CreateInterp();
+
+	tclres = Tcl_EvalFile(driver->interp, (char *) "lookup.tcl");
+	if (tclres != TCL_OK) {
+		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+			      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+			      "initializing tcldb: "
+			      "loading lookup.tcl failed: %s",
+			      driver->interp->result);
+		return (ISC_R_FAILURE);
+	}
+	*driverp = driver;
+	return (ISC_R_SUCCESS);
+}
+
+static void
+tcldb_driver_destroy(tcldb_driver_t **driverp) {
+	tcldb_driver_t *driver = *driverp;
+	Tcl_DeleteInterp(driver->interp);
+	isc_mem_put(driver->mctx, driver, sizeof(tcldb_driver_t));
+}
+
+/*
+ * This database operates on relative names.
+ *
+ * Any name will be interpreted as a pathname offset from the tclectory
+ * specified in the configuration file.
+ */
+static isc_result_t
+tcldb_lookup(const char *zone, const char *name, void *dbdata,
+	      dns_sdblookup_t *lookup)
+{
+	isc_result_t result = ISC_R_SUCCESS;
+	int tclres;
+	int rrc;	/* RR count */
+	char **rrv;	/* RR vector */
+	int i;
+	char *cmdv[3];
+	char *cmd;
+
+	tcldb_driver_t *driver = (tcldb_driver_t *) dbdata;
+
+	cmdv[0] = "lookup";
+	cmdv[1] = zone;
+	cmdv[2] = name;
+	cmd = Tcl_Merge(3, cmdv);
+	tclres = Tcl_Eval(driver->interp, cmd);
+	Tcl_Free(cmd);
+
+	if (tclres != TCL_OK) {
+		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+			      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+			      "zone '%s': tcl lookup function failed: %s",
+			      zone, driver->interp->result);
+		return (ISC_R_FAILURE);
+	}
+
+	if (strcmp(driver->interp->result, "NXDOMAIN") == 0) {
+		result = ISC_R_NOTFOUND;
+		goto fail;
+	}
+
+	tclres = Tcl_SplitList(driver->interp, driver->interp->result, &rrc, &rrv);
+	if (tclres != TCL_OK)
+		goto malformed;
+
+	for (i = 0; i < rrc; i++) {
+		isc_result_t tmpres;
+		int fieldc;	/* Field count */
+		char **fieldv;	/* Field vector */
+		tclres = Tcl_SplitList(driver->interp, rrv[i], &fieldc, &fieldv);
+		if (tclres != TCL_OK) {
+			tmpres = ISC_R_FAILURE;
+			goto failrr;
+		}
+		if (fieldc != 3)
+			goto malformed;
+		tmpres = dns_sdb_putrr(lookup, fieldv[0], atoi(fieldv[1]), fieldv[2]);
+		Tcl_Free((char *) fieldv);
+	failrr:
+		if (tmpres != ISC_R_SUCCESS)
+			result = tmpres;
+	}
+	Tcl_Free((char *) rrv);
+	if (result == ISC_R_SUCCESS)
+		return (result);
+
+ malformed:
+	isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+		      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+		      "zone '%s': malformed return value from tcl lookup function: %s",
+		      zone, driver->interp->result);
+	result = ISC_R_FAILURE;
+ fail:
+	return (result);
+}
+
+/*
+ * Each database stores the top-level tclectory as the dbdata opaque
+ * object.  The create() function allocates it.  argv[0] holds the top
+ * level tclectory.
+ */
+static isc_result_t
+tcldb_create(const char *zone, int argc, char **argv,
+	     void *driverdata, void **dbdata)
+{
+	tcldb_driver_t *driver = (tcldb_driver_t *) driverdata;
+
+	char *list = Tcl_Merge(argc, argv);
+	
+	Tcl_SetVar2(driver->interp, (char *) "dbargs", (char *) zone, list, 0);
+
+	Tcl_Free(list);
+
+	*dbdata = driverdata;
+	
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * This zone does not support zone transfer, so allnodes() is NULL.
+ */
+static dns_sdbmethods_t tcldb_methods = {
+	tcldb_lookup,
+	NULL, /* authority */
+	NULL, /* allnodes */
+	tcldb_create,
+	NULL /* destroy */
+};
+
+/*
+ * Initialize the tcldb driver.
+ */
+isc_result_t
+tcldb_init(void) {
+	isc_result_t result;
+	int flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA;
+	
+	result = tcldb_driver_create(ns_g_mctx, &the_driver);
+	if (result != ISC_R_SUCCESS)
+		return (result);
+	
+	return (dns_sdb_register("tcl", &tcldb_methods, the_driver, flags,
+				 ns_g_mctx, &tcldb));
+}
+
+/*
+ * Wrapper around dns_sdb_unregister().
+ */
+void
+tcldb_clear(void) {
+	dns_sdb_unregister(&tcldb);
+	tcldb_driver_destroy(&the_driver);
+}

contrib/sdb/tcl/tcldb.h

@@ -0,0 +1,6 @@
+
+#include <isc/types.h>
+
+isc_result_t tcldb_init(void);
+
+void tcldb_clear(void);

contrib/sdb/tcldb.c

@@ -0,0 +1,201 @@
+#include <config.h>
+
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/stat.h>
+
+#include <isc/mem.h>
+#include <isc/print.h>
+#include <isc/result.h>
+#include <isc/util.h>
+
+#include <dns/log.h>
+#include <dns/sdb.h>
+
+#include <named/globals.h>
+
+#include <tcl.h>
+
+#include <tcldb.h>
+
+/*
+ * A simple database driver that calls Tcl procedures to define
+ * the contents of the DNS namespace.
+ */
+
+static dns_sdbimplementation_t *tcldb = NULL;
+
+#define CHECK(op)						\
+	do { result = (op);					\
+		if (result != ISC_R_SUCCESS) return (result);	\
+	} while (0)
+
+typedef struct tcldb_driver {
+	isc_mem_t *mctx;
+	Tcl_Interp *interp;
+} tcldb_driver_t;
+
+static tcldb_driver_t *the_driver;
+
+static isc_result_t
+tcldb_driver_create(isc_mem_t *mctx, tcldb_driver_t **driverp) {
+	int tclres;
+	tcldb_driver_t *driver = isc_mem_get(mctx, sizeof(tcldb_driver_t));
+	if (driver == NULL)
+		return (ISC_R_NOMEMORY);
+	driver->mctx = mctx;
+	driver->interp = Tcl_CreateInterp();
+
+	tclres = Tcl_EvalFile(driver->interp, (char *) "lookup.tcl");
+	if (tclres != TCL_OK) {
+		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+			      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+			      "initializing tcldb: "
+			      "loading lookup.tcl failed: %s",
+			      driver->interp->result);
+		return (ISC_R_FAILURE);
+	}
+	*driverp = driver;
+	return (ISC_R_SUCCESS);
+}
+
+static void
+tcldb_driver_destroy(tcldb_driver_t **driverp) {
+	tcldb_driver_t *driver = *driverp;
+	Tcl_DeleteInterp(driver->interp);
+	isc_mem_put(driver->mctx, driver, sizeof(tcldb_driver_t));
+}
+
+/*
+ * This database operates on relative names.
+ *
+ * Any name will be interpreted as a pathname offset from the tclectory
+ * specified in the configuration file.
+ */
+static isc_result_t
+tcldb_lookup(const char *zone, const char *name, void *dbdata,
+	      dns_sdblookup_t *lookup)
+{
+	isc_result_t result = ISC_R_SUCCESS;
+	int tclres;
+	int rrc;	/* RR count */
+	char **rrv;	/* RR vector */
+	int i;
+	char *cmdv[3];
+	char *cmd;
+
+	tcldb_driver_t *driver = (tcldb_driver_t *) dbdata;
+
+	cmdv[0] = "lookup";
+	cmdv[1] = zone;
+	cmdv[2] = name;
+	cmd = Tcl_Merge(3, cmdv);
+	tclres = Tcl_Eval(driver->interp, cmd);
+	Tcl_Free(cmd);
+
+	if (tclres != TCL_OK) {
+		isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+			      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+			      "zone '%s': tcl lookup function failed: %s",
+			      zone, driver->interp->result);
+		return (ISC_R_FAILURE);
+	}
+
+	if (strcmp(driver->interp->result, "NXDOMAIN") == 0) {
+		result = ISC_R_NOTFOUND;
+		goto fail;
+	}
+
+	tclres = Tcl_SplitList(driver->interp, driver->interp->result, &rrc, &rrv);
+	if (tclres != TCL_OK)
+		goto malformed;
+
+	for (i = 0; i < rrc; i++) {
+		isc_result_t tmpres;
+		int fieldc;	/* Field count */
+		char **fieldv;	/* Field vector */
+		tclres = Tcl_SplitList(driver->interp, rrv[i], &fieldc, &fieldv);
+		if (tclres != TCL_OK) {
+			tmpres = ISC_R_FAILURE;
+			goto failrr;
+		}
+		if (fieldc != 3)
+			goto malformed;
+		tmpres = dns_sdb_putrr(lookup, fieldv[0], atoi(fieldv[1]), fieldv[2]);
+		Tcl_Free((char *) fieldv);
+	failrr:
+		if (tmpres != ISC_R_SUCCESS)
+			result = tmpres;
+	}
+	Tcl_Free((char *) rrv);
+	if (result == ISC_R_SUCCESS)
+		return (result);
+
+ malformed:
+	isc_log_write(dns_lctx, DNS_LOGCATEGORY_GENERAL,
+		      DNS_LOGMODULE_SDB, ISC_LOG_ERROR,
+		      "zone '%s': malformed return value from tcl lookup function: %s",
+		      zone, driver->interp->result);
+	result = ISC_R_FAILURE;
+ fail:
+	return (result);
+}
+
+/*
+ * Each database stores the top-level tclectory as the dbdata opaque
+ * object.  The create() function allocates it.  argv[0] holds the top
+ * level tclectory.
+ */
+static isc_result_t
+tcldb_create(const char *zone, int argc, char **argv,
+	     void *driverdata, void **dbdata)
+{
+	tcldb_driver_t *driver = (tcldb_driver_t *) driverdata;
+
+	char *list = Tcl_Merge(argc, argv);
+	
+	Tcl_SetVar2(driver->interp, (char *) "dbargs", (char *) zone, list, 0);
+
+	Tcl_Free(list);
+
+	*dbdata = driverdata;
+	
+	return (ISC_R_SUCCESS);
+}
+
+/*
+ * This zone does not support zone transfer, so allnodes() is NULL.
+ */
+static dns_sdbmethods_t tcldb_methods = {
+	tcldb_lookup,
+	NULL, /* authority */
+	NULL, /* allnodes */
+	tcldb_create,
+	NULL /* destroy */
+};
+
+/*
+ * Initialize the tcldb driver.
+ */
+isc_result_t
+tcldb_init(void) {
+	isc_result_t result;
+	int flags = DNS_SDBFLAG_RELATIVEOWNER | DNS_SDBFLAG_RELATIVERDATA;
+	
+	result = tcldb_driver_create(ns_g_mctx, &the_driver);
+	if (result != ISC_R_SUCCESS)
+		return (result);
+	
+	return (dns_sdb_register("tcl", &tcldb_methods, the_driver, flags,
+				 ns_g_mctx, &tcldb));
+}
+
+/*
+ * Wrapper around dns_sdb_unregister().
+ */
+void
+tcldb_clear(void) {
+	dns_sdb_unregister(&tcldb);
+	tcldb_driver_destroy(&the_driver);
+}

contrib/sdb/tcldb.h

@@ -0,0 +1,6 @@
+
+#include <isc/types.h>
+
+isc_result_t tcldb_init(void);
+
+void tcldb_clear(void);