diff options
Diffstat (limited to 'contrib/sdb/tcl/tcldb.c')
| -rw-r--r-- | contrib/sdb/tcl/tcldb.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/contrib/sdb/tcl/tcldb.c b/contrib/sdb/tcl/tcldb.c new file mode 100644 index 0000000..61be7df --- /dev/null +++ b/contrib/sdb/tcl/tcldb.c @@ -0,0 +1,238 @@ +/* + * Copyright (C) Internet Systems Consortium, Inc. ("ISC") + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + * + * See the COPYRIGHT file distributed with this work for additional + * information regarding copyright ownership. + */ + + +/* + * A simple database driver that calls a Tcl procedure to define + * the contents of the DNS namespace. The procedure is loaded + * from the file lookup.tcl; look at the comments there for + * more information. + */ + +#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> + +#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 = NULL; + +static dns_sdbimplementation_t *tcldb = NULL; + +static isc_result_t +tcldb_driver_create(isc_mem_t *mctx, tcldb_driver_t **driverp) { + int tclres; + isc_result_t result = ISC_R_SUCCESS; + 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); + result = ISC_R_FAILURE; + goto cleanup; + } + *driverp = driver; + return (ISC_R_SUCCESS); + + cleanup: + isc_mem_put(mctx, driver, sizeof(tcldb_driver_t)); + return (result); + +} + +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)); +} + +/* + * Perform a lookup, by invoking the Tcl procedure "lookup". + */ +#ifdef DNS_CLIENTINFO_VERSION +static isc_result_t +tcldb_lookup(const char *zone, const char *name, void *dbdata, + dns_sdblookup_t *lookup, dns_clientinfomethods_t *methods, + dns_clientinfo_t *clientinfo) +#else +static isc_result_t +tcldb_lookup(const char *zone, const char *name, void *dbdata, + dns_sdblookup_t *lookup) +#endif /* DNS_CLIENTINFO_VERSION */ +{ + isc_result_t result = ISC_R_SUCCESS; + int tclres; + int rrc; /* RR count */ + char **rrv; /* RR vector */ + int i; + char *cmdv[3]; + char *cmd; + +#ifdef DNS_CLIENTINFO_VERSION + UNUSED(methods); + UNUSED(clientinfo); +#endif /* DNS_CLIENTINFO_VERSION */ + + 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); +} + +/* + * Set up per-zone state. In our case, the database arguments of the + * zone are collected into a Tcl list and assigned to an element of + * the global array "dbargs". + */ +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 driver 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 */ + NULL /* lookup2 */ +}; + +/* + * 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) { + if (tcldb != NULL) + dns_sdb_unregister(&tcldb); + if (the_driver != NULL) + tcldb_driver_destroy(&the_driver); +} |