bin/named/server.c

	server.c revision 7027fd24a28b2f8de661b61fcf082f3851b20a32
/*
 * Copyright (C) 1999  Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

#include <config.h>

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <stdarg.h>

#include <isc/assertions.h>
#include <isc/error.h>
#include <isc/rwlock.h>
#include <isc/mem.h>
#include <isc/task.h>
#include <isc/thread.h>
#include <isc/result.h>
#include <isc/socket.h>
#include <isc/timer.h>
#include <isc/app.h>
#include <isc/dir.h>
#include <isc/util.h>

#include <dns/aclconf.h>
#include <dns/cache.h>
#include <dns/confparser.h>
#include <dns/types.h>
#include <dns/result.h>
#include <dns/master.h>
#include <dns/name.h>
#include <dns/fixedname.h>
#include <dns/rdata.h>
#include <dns/rdatalist.h>
#include <dns/rdataset.h>
#include <dns/rdatasetiter.h>
#include <dns/compress.h>
#include <dns/db.h>
#include <dns/dbtable.h>
#include <dns/message.h>
#include <dns/journal.h>
#include <dns/view.h>
#include <dns/zone.h>
#include <dns/zoneconf.h>
#include <dns/tsig.h>
#include <dns/tkey.h>

#include <named/types.h>
#include <named/globals.h>
#include <named/log.h>
#include <named/rootns.h>
#include <named/server.h>

typedef struct {
    isc_mem_t *     mctx;
    dns_viewlist_t      viewlist;
    dns_aclconfctx_t    *aclconf;
} ns_load_t;

static isc_task_t *     server_task;


static isc_result_t
create_default_view(dns_c_ctx_t *cctx, isc_mem_t *mctx,
            dns_rdataclass_t rdclass, dns_view_t **viewp)
{
    dns_view_t *view;
    dns_cache_t *cache;
    isc_result_t result;
    isc_int32_t cleaning_interval;

    REQUIRE(viewp != NULL && *viewp == NULL);

    /*
     * View.
     */
    view = NULL;
    result = dns_view_create(mctx, rdclass, "_default", &view);
    if (result != ISC_R_SUCCESS)
        return (result);

    /*
     * Cache.
     */
    cache = NULL;
    result = dns_cache_create(mctx, ns_g_taskmgr, ns_g_timermgr, rdclass,
                  "rbt", 0, NULL, &cache);
    if (result != ISC_R_SUCCESS)
        goto cleanup;
    dns_view_setcache(view, cache);
    cleaning_interval = 3600; /* Default is 1 hour. */
    (void) dns_c_ctx_getcleaninterval(cctx, &cleaning_interval);
    dns_cache_setcleaninginterval(cache, cleaning_interval);
    dns_cache_detach(&cache);

    /*
     * XXXRTH  Temporary support for loading cache contents.
     */
    if (ns_g_cachefile != NULL) {
        isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
                  NS_LOGMODULE_SERVER,
                  ISC_LOG_DEBUG(1), "loading cache '%s'",
                  ns_g_cachefile);
        result = dns_db_load(view->cachedb, ns_g_cachefile);
        if (result != ISC_R_SUCCESS)
            goto cleanup;
    }

    /*
     * Resolver.
     *
     * XXXRTH hardwired number of tasks.  Also, we'll need to
     * see if we are dealing with a shared dispatcher in this view.
     */
    result = dns_view_createresolver(view, ns_g_taskmgr, 31,
                     ns_g_socketmgr, ns_g_timermgr,
                     NULL);
    if (result != ISC_R_SUCCESS)
        goto cleanup;

    /*
     * We have default hints for class IN.
     */
    if (rdclass == dns_rdataclass_in)
        dns_view_sethints(view, ns_g_rootns);

    *viewp = view;

    return (ISC_R_SUCCESS);

 cleanup:
    dns_view_detach(&view);

    return (result);
}

/*
 * Create the special view that handles queries for
 * "version.bind. CH".   The version string returned is that
 * configured in 'configctx', or a compiled-in default if
 * there is no "version" configuration option.
 */
static isc_result_t
create_version_view(dns_c_ctx_t *configctx, dns_view_t **viewp) {
    dns_result_t result;
    dns_db_t *db = NULL;
    dns_zone_t *zone = NULL;
    dns_dbversion_t *dbver = NULL;
    dns_difftuple_t *tuple = NULL;
    dns_diff_t diff;
    dns_view_t *view = NULL;
    dns_name_t *origin;
    char *versiontext;
    char buf[256];
    isc_region_t r;
    size_t len;
    dns_rdata_t rdata;

    REQUIRE(viewp != NULL && *viewp == NULL);

    dns_diff_init(ns_g_mctx, &diff);

    (void) dns_c_ctx_getversion(configctx, &versiontext);
    if (versiontext == NULL)
        versiontext = ns_g_version;
    len = strlen(versiontext);
    if (len > 255)
        len = 255; /* Silently truncate. */
    buf[0] = len;
    memcpy(buf + 1, versiontext, len);

    r.base = buf;
    r.length = 1 + len;
    dns_rdata_fromregion(&rdata, dns_rdataclass_ch, dns_rdatatype_txt, &r);

    result = dns_zone_create(&zone, ns_g_mctx);
    if (result != ISC_R_SUCCESS)
        goto cleanup;
    result = dns_zone_setorigin(zone, "version.bind.");
    if (result != ISC_R_SUCCESS)
        goto cleanup;
    origin = dns_zone_getorigin(zone);

    result = dns_db_create(ns_g_mctx, "rbt", origin, ISC_FALSE,
                   dns_rdataclass_ch, 0, NULL, &db);
    if (result != ISC_R_SUCCESS)
        goto cleanup;

    result = dns_db_newversion(db, &dbver);
    if (result != DNS_R_SUCCESS)
        goto cleanup;

    dns_difftuple_create(ns_g_mctx, DNS_DIFFOP_ADD, origin,
                 0, &rdata, &tuple);
    dns_diff_append(&diff, &tuple);
    result = dns_diff_apply(&diff, db, dbver);
    if (result != DNS_R_SUCCESS)
        goto cleanup;

    dns_db_closeversion(db, &dbver, ISC_TRUE);

    result = dns_view_create(ns_g_mctx, dns_rdataclass_ch, "_version",
                 &view);
    if (result != ISC_R_SUCCESS)
        return (result);

    result = dns_zone_replacedb(zone, db, ISC_FALSE);
    if (result != DNS_R_SUCCESS)
        goto cleanup;

    result = dns_view_addzone(view, zone);
    if (result != DNS_R_SUCCESS)
        goto cleanup;

    dns_view_freeze(view);

    /* Transfer ownership. */
    *viewp = view;
    view = NULL;

    result = ISC_R_SUCCESS;

 cleanup:
    if (view != NULL)
        dns_view_detach(&view);
    if (zone != NULL)
        dns_zone_detach(&zone);
    if (dbver != NULL)
        dns_db_closeversion(db, &dbver, ISC_FALSE);
    if (db != NULL)
        dns_db_detach(&db);
    dns_diff_clear(&diff);

    return (result);
}

static isc_result_t
load_zone(dns_c_ctx_t *ctx, dns_c_zone_t *czone, dns_c_view_t *cview,
      void *uap)
{
    ns_load_t *lctx;
    dns_view_t *view, *tview, *pview;
    dns_zone_t *zone, *tzone;
    dns_name_t *origin;
    isc_result_t result;

    /*
     * Load (or reload) a zone.
     */

    lctx = uap;

    tzone = NULL;
    zone = NULL;
    pview = NULL;

    /*
     * Find the view.
     */
    view = NULL;
    if (cview != NULL) {
        result = dns_viewlist_find(&lctx->viewlist, cview->name,
                       czone->zclass, &view);
        if (result != ISC_R_SUCCESS)
            return (result);
    } else {
        result = dns_viewlist_find(&lctx->viewlist, "_default",
                       czone->zclass, &view);
        if (result == ISC_R_NOTFOUND) {
            /*
             * Create a default view.
             */
            tview = NULL;
            result = create_default_view(ctx, ns_g_mctx, czone->zclass,
                             &tview);
            if (result != ISC_R_SUCCESS)
                return (result);
            dns_view_attach(tview, &view);
            ISC_LIST_APPEND(lctx->viewlist, view, link);
        } else if (result != ISC_R_SUCCESS)
            return (result);
    }

    /*
     * Do we already have a production version of this view?
     */
    RWLOCK(&ns_g_viewlock, isc_rwlocktype_read);
    result = dns_viewlist_find(&ns_g_viewlist, view->name, view->rdclass,
                   &pview);
        RWUNLOCK(&ns_g_viewlock, isc_rwlocktype_read);
    if (result != ISC_R_NOTFOUND && result != ISC_R_SUCCESS)
        goto cleanup;

    /*
     * Create a new zone structure and configure it.
     */
    result = dns_zone_create(&zone, lctx->mctx);
    if (result != ISC_R_SUCCESS)
        return (result);
    result = dns_zone_configure(ns_g_lctx, ctx, lctx->aclconf, czone, zone);
    if (result != ISC_R_SUCCESS)
        return (result);

    if (dns_zone_gettype(zone) == dns_zone_hint) {
        INSIST(0);
    } else {
        /*
         * Check for duplicates in the new zone table.
         */
        origin = dns_zone_getorigin(zone);
        result = dns_view_findzone(view, origin, &tzone);
        if (result == ISC_R_SUCCESS) {
            /*
             * We already have this zone!
             */
            result = ISC_R_EXISTS;
            goto cleanup;
        }

        /*
         * Do we have the zone in the production view?
         */
        if (pview != NULL)
            result = dns_view_findzone(pview, origin, &tzone);
        else
            result = ISC_R_NOTFOUND;
        if (result == ISC_R_SUCCESS) {
            /*
             * Yes.
             *
             * If the production zone's configuration is
             * the same as the new zone's, we can use the
             * production zone.
             */
            if (dns_zone_equal(zone, tzone))
                result = dns_view_addzone(view, tzone);
            else
                result = dns_view_addzone(view, zone);
        } else if (result == ISC_R_NOTFOUND) {
            /*
             * This is a new zone.
             */
            result = dns_view_addzone(view, zone);
            if (result != DNS_R_SUCCESS)
                goto cleanup;

            result = dns_zonemgr_managezone(ns_g_zonemgr, zone);
            if (result != DNS_R_SUCCESS)
                goto cleanup;
        }
    }

 cleanup:
    if (tzone != NULL)
        dns_zone_detach(&tzone);
    if (zone != NULL)
        dns_zone_detach(&zone);
    if (pview != NULL)
        dns_view_detach(&pview);
    if (view != NULL)
        dns_view_detach(&view);

    return (result);
}

/* XXX will need error recovery for reconfig */
static void
configure_server_acl(dns_c_ctx_t *cctx, dns_aclconfctx_t *actx, isc_mem_t *mctx,
             isc_result_t (*getcacl)(dns_c_ctx_t *, dns_c_ipmatchlist_t **),
              dns_acl_t **aclp)
{
    isc_result_t result;
    dns_c_ipmatchlist_t *cacl = NULL;
    if (*aclp != NULL)
        dns_acl_detach(aclp);
    (void) (*getcacl)(cctx, &cacl);
    if (cacl != NULL) {
        result = dns_acl_fromconfig(cacl, cctx, actx, mctx, aclp);
        if (result != DNS_R_SUCCESS)
            ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                    "server ACL setup failed");
    }
}

static void
load_configuration(const char *filename, ns_server_t *server) {
    isc_result_t result;
    ns_load_t lctx;
    dns_c_cbks_t callbacks;
    dns_c_ctx_t *configctx;
    dns_view_t *view, *view_next;
    dns_viewlist_t oviewlist;
    dns_aclconfctx_t aclconfctx;

    dns_aclconfctx_init(&aclconfctx);

    lctx.mctx = ns_g_mctx;
    lctx.aclconf = &aclconfctx;
    ISC_LIST_INIT(lctx.viewlist);

    callbacks.zonecbk = load_zone;
    callbacks.zonecbkuap = &lctx;
    callbacks.optscbk = NULL;
    callbacks.optscbkuap = NULL;

    isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
              ISC_LOG_INFO, "loading '%s'", filename);

    configctx = NULL;
    result = dns_c_parse_namedconf(filename, ns_g_mctx, &configctx,
                       &callbacks);
    if (result != ISC_R_SUCCESS) {
#ifdef notyet
        for (view = ISC_LIST_HEAD(lctx.viewlist);
             view != NULL;
             view = view_next) {
            view_next = ISC_LIST_NEXT(view, link);
            ISC_LIST_UNLINK(lctx.viewlist, view, link);
            dns_view_detach(&view);
        }
#endif
        ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                "load of '%s' failed", filename);
    }

    /*
     * Configure various server options.
     */
    (void) dns_c_ctx_getrecursion(configctx, &server->recursion);
    (void) dns_c_ctx_getauthnxdomain(configctx, &server->auth_nxdomain);
    (void) dns_c_ctx_gettransferformat(configctx, &server->transfer_format);

    configure_server_acl(configctx, &aclconfctx, ns_g_mctx,
                 dns_c_ctx_getqueryacl, &server->queryacl);

    configure_server_acl(configctx, &aclconfctx, ns_g_mctx,
                 dns_c_ctx_getrecursionacl, &server->recursionacl);

    configure_server_acl(configctx, &aclconfctx, ns_g_mctx,
                 dns_c_ctx_gettransferacl, &server->transferacl);

    /*
     * If we haven't created any views, create a default view for class
     * IN.  (We're a caching-only server.)
     */
    if (ISC_LIST_EMPTY(lctx.viewlist)) {
        view = NULL;
        result = create_default_view(configctx, ns_g_mctx,
                          dns_rdataclass_in, &view);
        if (result != ISC_R_SUCCESS)
            ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                    "could not create default view");
        ISC_LIST_APPEND(lctx.viewlist, view, link);
    }

    /*
     * Freeze the views.
     */
    for (view = ISC_LIST_HEAD(lctx.viewlist);
         view != NULL;
         view = ISC_LIST_NEXT(view, link))
        dns_view_freeze(view);

    /*
     * Create the version view.
     */
    view = NULL;
    result = create_version_view(configctx, &view);
    if (result != ISC_R_SUCCESS)
        ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                "could not create version view");
    ISC_LIST_APPEND(lctx.viewlist, view, link);
    view = NULL;

    /*
     * Change directory.
     */
    if (configctx->options != NULL &&
        configctx->options->directory != NULL) {
        result = isc_dir_chdir(configctx->options->directory);
        if (result != ISC_R_SUCCESS)
            ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                    "change directory to '%s' failed: %s",
                    configctx->options->directory,
                    isc_result_totext(result));
    }

    /*
     * Load zones.
     */
    for (view = ISC_LIST_HEAD(lctx.viewlist);
         view != NULL;
         view = view_next) {
        view_next = ISC_LIST_NEXT(view, link);
        dns_view_load(view);
    }

    /*
     * Force zone maintenance.  Do this after loading
     * so that we know when we need to force AXFR of
     * slave zones whose master files are missing.
     */
    dns_zonemgr_forcemaint(ns_g_zonemgr);

    /*
     * Put the configuration into production.
     */

    RWLOCK(&ns_g_viewlock, isc_rwlocktype_write);

    oviewlist = ns_g_viewlist;
    ns_g_viewlist = lctx.viewlist;

    RWUNLOCK(&ns_g_viewlock, isc_rwlocktype_write);

    /*
     * Cleanup old configuration.
     */

    for (view = ISC_LIST_HEAD(oviewlist);
         view != NULL;
         view = view_next) {
        view_next = ISC_LIST_NEXT(view, link);
        ISC_LIST_UNLINK(oviewlist, view, link);
        dns_view_detach(&view);
    }

    /*
     * Load the TSIG information from the configuration
     */
        result = dns_tsig_init(ns_g_lctx, configctx, ns_g_mctx);
        if (result != ISC_R_SUCCESS)
                ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                "dns_tsig_init() failed: %s",
                                isc_result_totext(result));

    /*
     * Load the TKEY information from the configuration
     */
    result = dns_tkey_init(ns_g_lctx, configctx, ns_g_mctx);
    if (result != ISC_R_SUCCESS) {
        ns_server_fatal(NS_LOGMODULE_SERVER, ISC_FALSE,
                "dns_tkey_init() failed: %s",
                isc_result_totext(result));
    }

    dns_aclconfctx_destroy(&aclconfctx);

    dns_c_ctx_delete(&configctx);


}

static void
run_server(isc_task_t *task, isc_event_t *event) {
    ns_server_t *server = (ns_server_t *) event->arg;
    (void)task;

    isc_event_free(&event);

    load_configuration(ns_g_conffile, server);

    ns_interfacemgr_scan(ns_g_interfacemgr);

    isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
              ISC_LOG_INFO, "running");
}

static void
shutdown_server(isc_task_t *task, isc_event_t *event) {
    dns_view_t *view, *view_next;
    ns_server_t *server = (ns_server_t *) event->arg;

    (void)task;

    isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
              ISC_LOG_INFO, "shutting down");

    RWLOCK(&ns_g_viewlock, isc_rwlocktype_write);

    for (view = ISC_LIST_HEAD(ns_g_viewlist);
         view != NULL;
         view = view_next) {
        view_next = ISC_LIST_NEXT(view, link);
        ISC_LIST_UNLINK(ns_g_viewlist, view, link);
        dns_view_detach(&view);
    }

    dns_tkey_destroy();
    dns_tsig_destroy();

    RWUNLOCK(&ns_g_viewlock, isc_rwlocktype_write);

    isc_task_detach(&server_task);

    dns_zonemgr_destroy(&ns_g_zonemgr);

    ns_rootns_destroy();

    ns_server_destroy(&server);

    isc_event_free(&event);
}

isc_result_t
ns_server_create(isc_mem_t *mctx, ns_server_t **serverp) {
    ns_server_t *server = isc_mem_get(mctx, sizeof(*server));
    if (server == NULL)
        return (ISC_R_NOMEMORY);
    server->mctx = mctx;

    /* Initialize. */
    server->recursion = ISC_TRUE;
    server->auth_nxdomain = ISC_FALSE; /* Was true in BIND 8 */
    server->transfer_format = dns_one_answer;

    server->queryacl = NULL;
    server->recursionacl = NULL;
    server->transferacl = NULL;

    server->magic = NS_SERVER_MAGIC;
    *serverp = server;
    return (ISC_R_SUCCESS);
}

void
ns_server_destroy(ns_server_t **serverp) {
    ns_server_t *server = *serverp;
    REQUIRE(NS_SERVER_VALID(server));

    if (server->queryacl != NULL)
        dns_acl_detach(&server->queryacl);
    if (server->recursionacl != NULL)
        dns_acl_detach(&server->recursionacl);
    if (server->transferacl != NULL)
        dns_acl_detach(&server->transferacl);

    server->magic = 0;
    isc_mem_put(server->mctx, server, sizeof(*server));
}

isc_result_t
ns_server_init() {
    isc_result_t result;

    /*
     * Create the server object.
     */
    result = ns_server_create(ns_g_mctx, &ns_g_server);
    if (result != ISC_R_SUCCESS)
        return (result);
    /*
     * Setup default root server hints.
     */
    result = ns_rootns_init();
    if (result != ISC_R_SUCCESS)
        return (result);

    result = dns_zonemgr_create(ns_g_mctx, ns_g_taskmgr, ns_g_timermgr,
                    ns_g_socketmgr, &ns_g_zonemgr);
    if (result != ISC_R_SUCCESS)
        return (result);

    /*
     * Setup the server task, which is responsible for coordinating
     * startup and shutdown of the server.
     */
    result = isc_task_create(ns_g_taskmgr, ns_g_mctx, 0, &server_task);
    if (result != ISC_R_SUCCESS)
        goto cleanup_rootns;
    result = isc_task_onshutdown(server_task, shutdown_server, ns_g_server);
    if (result != ISC_R_SUCCESS)
        goto cleanup_task;
    result = isc_app_onrun(ns_g_mctx, server_task, run_server, ns_g_server);
    if (result != ISC_R_SUCCESS)
        goto cleanup_task;

    return (ISC_R_SUCCESS);

    /* XXXRTH  Add zonemgr, and version view cleanups. */

 cleanup_task:
    isc_task_detach(&server_task);

 cleanup_rootns:
    ns_rootns_destroy();

    return (result);
}

void
ns_server_fatal(isc_logmodule_t *module, isc_boolean_t want_core,
        const char *format, ...)
{
    va_list args;

    va_start(args, format);
    isc_log_vwrite(ns_g_lctx, NS_LOGCATEGORY_GENERAL, module,
               ISC_LOG_CRITICAL, format, args);
    va_end(args);
    isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL, NS_LOGMODULE_SERVER,
              ISC_LOG_CRITICAL, "exiting (due to fatal error)");

    if (want_core && ns_g_coreok)
        abort();
    exit(1);
}