[apple/network_cmds.git] / unbound / services / localzone.c

/*
 * services/localzone.c - local zones authority service.
 *
 * Copyright (c) 2007, NLnet Labs. All rights reserved.
 *
 * This software is open source.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * 
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * Neither the name of the NLNET LABS nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * \file
 *
 * This file contains functions to enable local zone authority service.
 */
#include "config.h"
#include "services/localzone.h"
#include "ldns/str2wire.h"
#include "ldns/sbuffer.h"
#include "util/regional.h"
#include "util/config_file.h"
#include "util/data/dname.h"
#include "util/data/packed_rrset.h"
#include "util/data/msgencode.h"
#include "util/net_help.h"
#include "util/data/msgreply.h"
#include "util/data/msgparse.h"

struct local_zones* 
local_zones_create(void)
{
        struct local_zones* zones = (struct local_zones*)calloc(1, 
                sizeof(*zones));
        if(!zones)
                return NULL;
        rbtree_init(&zones->ztree, &local_zone_cmp);
        lock_rw_init(&zones->lock);
        lock_protect(&zones->lock, &zones->ztree, sizeof(zones->ztree));
        /* also lock protects the rbnode's in struct local_zone */
        return zones;
}

/** helper traverse to delete zones */
static void 
lzdel(rbnode_t* n, void* ATTR_UNUSED(arg))
{
        struct local_zone* z = (struct local_zone*)n->key;
        local_zone_delete(z);
}

void 
local_zones_delete(struct local_zones* zones)
{
        if(!zones)
                return;
        lock_rw_destroy(&zones->lock);
        /* walk through zones and delete them all */
        traverse_postorder(&zones->ztree, lzdel, NULL);
        free(zones);
}

void 
local_zone_delete(struct local_zone* z)
{
        if(!z)
                return;
        lock_rw_destroy(&z->lock);
        regional_destroy(z->region);
        free(z->name);
        free(z);
}

int 
local_zone_cmp(const void* z1, const void* z2)
{
        /* first sort on class, so that hierarchy can be maintained within
         * a class */
        struct local_zone* a = (struct local_zone*)z1;
        struct local_zone* b = (struct local_zone*)z2;
        int m;
        if(a->dclass != b->dclass) {
                if(a->dclass < b->dclass)
                        return -1;
                return 1;
        }
        return dname_lab_cmp(a->name, a->namelabs, b->name, b->namelabs, &m);
}

int 
local_data_cmp(const void* d1, const void* d2)
{
        struct local_data* a = (struct local_data*)d1;
        struct local_data* b = (struct local_data*)d2;
        int m;
        return dname_canon_lab_cmp(a->name, a->namelabs, b->name, 
                b->namelabs, &m);
}

/* form wireformat from text format domain name */
int
parse_dname(const char* str, uint8_t** res, size_t* len, int* labs)
{
        *res = sldns_str2wire_dname(str, len);
        *labs = 0;
        if(!*res) {
                log_err("cannot parse name %s", str);
                return 0;
        }
        *labs = dname_count_size_labels(*res, len);
        return 1;
}

/** create a new localzone */
static struct local_zone*
local_zone_create(uint8_t* nm, size_t len, int labs, 
        enum localzone_type t, uint16_t dclass)
{
        struct local_zone* z = (struct local_zone*)calloc(1, sizeof(*z));
        if(!z) {
                return NULL;
        }
        z->node.key = z;
        z->dclass = dclass;
        z->type = t;
        z->name = nm;
        z->namelen = len;
        z->namelabs = labs;
        lock_rw_init(&z->lock);
        z->region = regional_create();
        if(!z->region) {
                free(z);
                return NULL;
        }
        rbtree_init(&z->data, &local_data_cmp);
        lock_protect(&z->lock, &z->parent, sizeof(*z)-sizeof(rbnode_t));
        /* also the zones->lock protects node, parent, name*, class */
        return z;
}

/** enter a new zone with allocated dname returns with WRlock */
static struct local_zone*
lz_enter_zone_dname(struct local_zones* zones, uint8_t* nm, size_t len, 
        int labs, enum localzone_type t, uint16_t c)
{
        struct local_zone* z = local_zone_create(nm, len, labs, t, c);
        if(!z) {
                log_err("out of memory");
                return NULL;
        }

        /* add to rbtree */
        lock_rw_wrlock(&zones->lock);
        lock_rw_wrlock(&z->lock);
        if(!rbtree_insert(&zones->ztree, &z->node)) {
                log_warn("duplicate local-zone");
                lock_rw_unlock(&z->lock);
                local_zone_delete(z);
                lock_rw_unlock(&zones->lock);
                return NULL;
        }
        lock_rw_unlock(&zones->lock);
        return z;
}

/** enter a new zone */
static struct local_zone*
lz_enter_zone(struct local_zones* zones, const char* name, const char* type,
        uint16_t dclass)
{
        struct local_zone* z;
        enum localzone_type t;
        uint8_t* nm;
        size_t len;
        int labs;
        if(!parse_dname(name, &nm, &len, &labs)) {
                log_err("bad zone name %s %s", name, type);
                return NULL;
        }
        if(!local_zone_str2type(type, &t)) {
                log_err("bad lz_enter_zone type %s %s", name, type);
                free(nm);
                return NULL;
        }
        if(!(z=lz_enter_zone_dname(zones, nm, len, labs, t, dclass))) {
                log_err("could not enter zone %s %s", name, type);
                return NULL;
        }
        return z;
}

/** return name and class and rdata of rr; parses string */
static int
get_rr_content(const char* str, uint8_t** nm, uint16_t* type,
        uint16_t* dclass, time_t* ttl, uint8_t* rr, size_t len,
        uint8_t** rdata, size_t* rdata_len)
{
        size_t dname_len = 0;
        int e = sldns_str2wire_rr_buf(str, rr, &len, &dname_len, 3600,
                NULL, 0, NULL, 0);
        if(e) {
                log_err("error parsing local-data at %d: '%s': %s",
                        LDNS_WIREPARSE_OFFSET(e), str,
                        sldns_get_errorstr_parse(e));
                return 0;
        }
        *nm = memdup(rr, dname_len);
        if(!*nm) {
                log_err("out of memory");
                return 0;
        }
        *dclass = sldns_wirerr_get_class(rr, len, dname_len);
        *type = sldns_wirerr_get_type(rr, len, dname_len);
        *ttl = (time_t)sldns_wirerr_get_ttl(rr, len, dname_len);
        *rdata = sldns_wirerr_get_rdatawl(rr, len, dname_len);
        *rdata_len = sldns_wirerr_get_rdatalen(rr, len, dname_len)+2;
        return 1;
}

/** return name and class of rr; parses string */
static int
get_rr_nameclass(const char* str, uint8_t** nm, uint16_t* dclass)
{
        uint8_t rr[LDNS_RR_BUF_SIZE];
        size_t len = sizeof(rr), dname_len = 0;
        int s = sldns_str2wire_rr_buf(str, rr, &len, &dname_len, 3600,
                NULL, 0, NULL, 0);
        if(s != 0) {
                log_err("error parsing local-data at %d '%s': %s",
                        LDNS_WIREPARSE_OFFSET(s), str,
                        sldns_get_errorstr_parse(s));
                return 0;
        }
        *nm = memdup(rr, dname_len);
        *dclass = sldns_wirerr_get_class(rr, len, dname_len);
        if(!*nm) {
                log_err("out of memory");
                return 0;
        }
        return 1;
}

/**
 * Find an rrset in local data structure.
 * @param data: local data domain name structure.
 * @param type: type to look for (host order).
 * @return rrset pointer or NULL if not found.
 */
static struct local_rrset*
local_data_find_type(struct local_data* data, uint16_t type)
{
        struct local_rrset* p;
        type = htons(type);
        for(p = data->rrsets; p; p = p->next) {
                if(p->rrset->rk.type == type)
                        return p;
        }
        return NULL;
}

/** check for RR duplicates */
static int
rr_is_duplicate(struct packed_rrset_data* pd, uint8_t* rdata, size_t rdata_len)
{
        size_t i;
        for(i=0; i<pd->count; i++) {
                if(pd->rr_len[i] == rdata_len &&
                        memcmp(pd->rr_data[i], rdata, rdata_len) == 0)
                        return 1;
        }
        return 0;
}

/** new local_rrset */
static struct local_rrset*
new_local_rrset(struct regional* region, struct local_data* node,
        uint16_t rrtype, uint16_t rrclass)
{
        struct packed_rrset_data* pd;
        struct local_rrset* rrset = (struct local_rrset*)
                regional_alloc_zero(region, sizeof(*rrset));
        if(!rrset) {
                log_err("out of memory");
                return NULL;
        }
        rrset->next = node->rrsets;
        node->rrsets = rrset;
        rrset->rrset = (struct ub_packed_rrset_key*)
                regional_alloc_zero(region, sizeof(*rrset->rrset));
        if(!rrset->rrset) {
                log_err("out of memory");
                return NULL;
        }
        rrset->rrset->entry.key = rrset->rrset;
        pd = (struct packed_rrset_data*)regional_alloc_zero(region,
                sizeof(*pd));
        if(!pd) {
                log_err("out of memory");
                return NULL;
        }
        pd->trust = rrset_trust_prim_noglue;
        pd->security = sec_status_insecure;
        rrset->rrset->entry.data = pd;
        rrset->rrset->rk.dname = node->name;
        rrset->rrset->rk.dname_len = node->namelen;
        rrset->rrset->rk.type = htons(rrtype);
        rrset->rrset->rk.rrset_class = htons(rrclass);
        return rrset;
}

/** insert RR into RRset data structure; Wastes a couple of bytes */
static int
insert_rr(struct regional* region, struct packed_rrset_data* pd,
        uint8_t* rdata, size_t rdata_len, time_t ttl)
{
        size_t* oldlen = pd->rr_len;
        time_t* oldttl = pd->rr_ttl;
        uint8_t** olddata = pd->rr_data;

        /* add RR to rrset */
        pd->count++;
        pd->rr_len = regional_alloc(region, sizeof(*pd->rr_len)*pd->count);
        pd->rr_ttl = regional_alloc(region, sizeof(*pd->rr_ttl)*pd->count);
        pd->rr_data = regional_alloc(region, sizeof(*pd->rr_data)*pd->count);
        if(!pd->rr_len || !pd->rr_ttl || !pd->rr_data) {
                log_err("out of memory");
                return 0;
        }
        if(pd->count > 1) {
                memcpy(pd->rr_len+1, oldlen, 
                        sizeof(*pd->rr_len)*(pd->count-1));
                memcpy(pd->rr_ttl+1, oldttl, 
                        sizeof(*pd->rr_ttl)*(pd->count-1));
                memcpy(pd->rr_data+1, olddata, 
                        sizeof(*pd->rr_data)*(pd->count-1));
        }
        pd->rr_len[0] = rdata_len;
        pd->rr_ttl[0] = ttl;
        pd->rr_data[0] = regional_alloc_init(region, rdata, rdata_len);
        if(!pd->rr_data[0]) {
                log_err("out of memory");
                return 0;
        }
        return 1;
}

/** find a data node by exact name */
static struct local_data* 
lz_find_node(struct local_zone* z, uint8_t* nm, size_t nmlen, int nmlabs)
{
        struct local_data key;
        key.node.key = &key;
        key.name = nm;
        key.namelen = nmlen;
        key.namelabs = nmlabs;
        return (struct local_data*)rbtree_search(&z->data, &key.node);
}

/** find a node, create it if not and all its empty nonterminal parents */
static int
lz_find_create_node(struct local_zone* z, uint8_t* nm, size_t nmlen, 
        int nmlabs, struct local_data** res)
{
        struct local_data* ld = lz_find_node(z, nm, nmlen, nmlabs);
        if(!ld) {
                /* create a domain name to store rr. */
                ld = (struct local_data*)regional_alloc_zero(z->region,
                        sizeof(*ld));
                if(!ld) {
                        log_err("out of memory adding local data");
                        return 0;
                }
                ld->node.key = ld;
                ld->name = regional_alloc_init(z->region, nm, nmlen);
                if(!ld->name) {
                        log_err("out of memory");
                        return 0;
                }
                ld->namelen = nmlen;
                ld->namelabs = nmlabs;
                if(!rbtree_insert(&z->data, &ld->node)) {
                        log_assert(0); /* duplicate name */
                }
                /* see if empty nonterminals need to be created */
                if(nmlabs > z->namelabs) {
                        dname_remove_label(&nm, &nmlen);
                        if(!lz_find_create_node(z, nm, nmlen, nmlabs-1, res))
                                return 0;
                }
        }
        *res = ld;
        return 1;
}

/** enter data RR into auth zone */
static int
lz_enter_rr_into_zone(struct local_zone* z, const char* rrstr)
{
        uint8_t* nm;
        size_t nmlen;
        int nmlabs;
        struct local_data* node;
        struct local_rrset* rrset;
        struct packed_rrset_data* pd;
        uint16_t rrtype = 0, rrclass = 0;
        time_t ttl = 0;
        uint8_t rr[LDNS_RR_BUF_SIZE];
        uint8_t* rdata;
        size_t rdata_len;
        if(!get_rr_content(rrstr, &nm, &rrtype, &rrclass, &ttl, rr, sizeof(rr),
                &rdata, &rdata_len)) {
                log_err("bad local-data: %s", rrstr);
                return 0;
        }
        log_assert(z->dclass == rrclass);
        if(z->type == local_zone_redirect &&
                query_dname_compare(z->name, nm) != 0) {
                log_err("local-data in redirect zone must reside at top of zone"
                        ", not at %s", rrstr);
                free(nm);
                return 0;
        }
        nmlabs = dname_count_size_labels(nm, &nmlen);
        if(!lz_find_create_node(z, nm, nmlen, nmlabs, &node)) {
                free(nm);
                return 0;
        }
        log_assert(node);
        free(nm);

        rrset = local_data_find_type(node, rrtype);
        if(!rrset) {
                rrset = new_local_rrset(z->region, node, rrtype, rrclass);
                if(!rrset)
                        return 0;
                if(query_dname_compare(node->name, z->name) == 0) {
                        if(rrtype == LDNS_RR_TYPE_NSEC)
                          rrset->rrset->rk.flags = PACKED_RRSET_NSEC_AT_APEX;
                        if(rrtype == LDNS_RR_TYPE_SOA)
                                z->soa = rrset->rrset;
                }
        } 
        pd = (struct packed_rrset_data*)rrset->rrset->entry.data;
        log_assert(rrset && pd);

        /* check for duplicate RR */
        if(rr_is_duplicate(pd, rdata, rdata_len)) {
                verbose(VERB_ALGO, "ignoring duplicate RR: %s", rrstr);
                return 1;
        } 
        return insert_rr(z->region, pd, rdata, rdata_len, ttl);
}

/** enter a data RR into auth data; a zone for it must exist */
static int
lz_enter_rr_str(struct local_zones* zones, const char* rr)
{
        uint8_t* rr_name;
        uint16_t rr_class;
        size_t len;
        int labs;
        struct local_zone* z;
        int r;
        if(!get_rr_nameclass(rr, &rr_name, &rr_class)) {
                log_err("bad rr %s", rr);
                return 0;
        }
        labs = dname_count_size_labels(rr_name, &len);
        lock_rw_rdlock(&zones->lock);
        z = local_zones_lookup(zones, rr_name, len, labs, rr_class);
        if(!z) {
                lock_rw_unlock(&zones->lock);
                fatal_exit("internal error: no zone for rr %s", rr);
        }
        lock_rw_wrlock(&z->lock);
        lock_rw_unlock(&zones->lock);
        free(rr_name);
        r = lz_enter_rr_into_zone(z, rr);
        lock_rw_unlock(&z->lock);
        return r;
}

/** parse local-zone: statements */
static int
lz_enter_zones(struct local_zones* zones, struct config_file* cfg)
{
        struct config_str2list* p;
        struct local_zone* z;
        for(p = cfg->local_zones; p; p = p->next) {
                if(!(z=lz_enter_zone(zones, p->str, p->str2, 
                        LDNS_RR_CLASS_IN)))
                        return 0;
                lock_rw_unlock(&z->lock);
        }
        return 1;
}

/** lookup a zone in rbtree; exact match only; SLOW due to parse */
static int
lz_exists(struct local_zones* zones, const char* name)
{
        struct local_zone z;
        z.node.key = &z;
        z.dclass = LDNS_RR_CLASS_IN;
        if(!parse_dname(name, &z.name, &z.namelen, &z.namelabs)) {
                log_err("bad name %s", name);
                return 0;
        }
        lock_rw_rdlock(&zones->lock);
        if(rbtree_search(&zones->ztree, &z.node)) {
                lock_rw_unlock(&zones->lock);
                free(z.name);
                return 1;
        }
        lock_rw_unlock(&zones->lock);
        free(z.name);
        return 0;
}

/** lookup a zone in cfg->nodefault list */
static int
lz_nodefault(struct config_file* cfg, const char* name)
{
        struct config_strlist* p;
        size_t len = strlen(name);
        if(len == 0) return 0;
        if(name[len-1] == '.') len--;

        for(p = cfg->local_zones_nodefault; p; p = p->next) {
                /* compare zone name, lowercase, compare without ending . */
                if(strncasecmp(p->str, name, len) == 0 && 
                        (strlen(p->str) == len || (strlen(p->str)==len+1 &&
                        p->str[len] == '.')))
                        return 1;
        }
        return 0;
}

/** enter AS112 default zone */
static int
add_as112_default(struct local_zones* zones, struct config_file* cfg,
        const char* name)
{
        struct local_zone* z;
        char str[1024]; /* known long enough */
        if(lz_exists(zones, name) || lz_nodefault(cfg, name))
                return 1; /* do not enter default content */
        if(!(z=lz_enter_zone(zones, name, "static", LDNS_RR_CLASS_IN)))
                return 0;
        snprintf(str, sizeof(str), "%s 10800 IN SOA localhost. "
                "nobody.invalid. 1 3600 1200 604800 10800", name);
        if(!lz_enter_rr_into_zone(z, str)) {
                lock_rw_unlock(&z->lock);
                return 0;
        }
        snprintf(str, sizeof(str), "%s 10800 IN NS localhost. ", name);
        if(!lz_enter_rr_into_zone(z, str)) {
                lock_rw_unlock(&z->lock);
                return 0;
        }
        lock_rw_unlock(&z->lock);
        return 1;
}

/** enter default zones */
static int
lz_enter_defaults(struct local_zones* zones, struct config_file* cfg)
{
        struct local_zone* z;

        /* this list of zones is from RFC 6303 */

        /* block localhost level zones, first, later the LAN zones */

        /* localhost. zone */
        if(!lz_exists(zones, "localhost.") &&
                !lz_nodefault(cfg, "localhost.")) {
                if(!(z=lz_enter_zone(zones, "localhost.", "static", 
                        LDNS_RR_CLASS_IN)) ||
                   !lz_enter_rr_into_zone(z,
                        "localhost. 10800 IN NS localhost.") ||
                   !lz_enter_rr_into_zone(z,
                        "localhost. 10800 IN SOA localhost. nobody.invalid. "
                        "1 3600 1200 604800 10800") ||
                   !lz_enter_rr_into_zone(z,
                        "localhost. 10800 IN A 127.0.0.1") ||
                   !lz_enter_rr_into_zone(z,
                        "localhost. 10800 IN AAAA ::1")) {
                        log_err("out of memory adding default zone");
                        if(z) { lock_rw_unlock(&z->lock); }
                        return 0;
                }
                lock_rw_unlock(&z->lock);
        }
        /* reverse ip4 zone */
        if(!lz_exists(zones, "127.in-addr.arpa.") &&
                !lz_nodefault(cfg, "127.in-addr.arpa.")) {
                if(!(z=lz_enter_zone(zones, "127.in-addr.arpa.", "static", 
                        LDNS_RR_CLASS_IN)) ||
                   !lz_enter_rr_into_zone(z,
                        "127.in-addr.arpa. 10800 IN NS localhost.") ||
                   !lz_enter_rr_into_zone(z,
                        "127.in-addr.arpa. 10800 IN SOA localhost. "
                        "nobody.invalid. 1 3600 1200 604800 10800") ||
                   !lz_enter_rr_into_zone(z,
                        "1.0.0.127.in-addr.arpa. 10800 IN PTR localhost.")) {
                        log_err("out of memory adding default zone");
                        if(z) { lock_rw_unlock(&z->lock); }
                        return 0;
                }
                lock_rw_unlock(&z->lock);
        }
        /* reverse ip6 zone */
        if(!lz_exists(zones, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.") &&
                !lz_nodefault(cfg, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.")) {
                if(!(z=lz_enter_zone(zones, "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.", "static", 
                        LDNS_RR_CLASS_IN)) ||
                   !lz_enter_rr_into_zone(z,
                        "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa. 10800 IN NS localhost.") ||
                   !lz_enter_rr_into_zone(z,
                        "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa. 10800 IN SOA localhost. "
                        "nobody.invalid. 1 3600 1200 604800 10800") ||
                   !lz_enter_rr_into_zone(z,
                        "1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa. 10800 IN PTR localhost.")) {
                        log_err("out of memory adding default zone");
                        if(z) { lock_rw_unlock(&z->lock); }
                        return 0;
                }
                lock_rw_unlock(&z->lock);
        }

        /* if unblock lan-zones, then do not add the zones below.
         * we do add the zones above, about 127.0.0.1, because localhost is
         * not on the lan. */
        if(cfg->unblock_lan_zones)
                return 1;

        /* block LAN level zones */
        if (    !add_as112_default(zones, cfg, "10.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "16.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "17.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "18.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "19.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "20.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "21.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "22.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "23.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "24.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "25.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "26.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "27.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "28.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "29.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "30.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "31.172.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "168.192.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "0.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "64.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "65.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "66.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "67.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "68.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "69.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "70.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "71.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "72.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "73.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "74.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "75.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "76.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "77.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "78.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "79.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "80.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "81.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "82.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "83.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "84.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "85.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "86.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "87.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "88.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "89.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "90.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "91.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "92.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "93.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "94.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "95.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "96.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "97.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "98.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "99.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "100.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "101.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "102.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "103.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "104.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "105.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "106.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "107.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "108.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "109.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "110.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "111.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "112.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "113.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "114.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "115.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "116.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "117.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "118.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "119.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "120.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "121.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "122.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "123.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "124.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "125.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "126.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "127.100.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "254.169.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "2.0.192.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "100.51.198.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "113.0.203.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "255.255.255.255.in-addr.arpa.") ||
                !add_as112_default(zones, cfg, "0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "d.f.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "8.e.f.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "9.e.f.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "a.e.f.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "b.e.f.ip6.arpa.") ||
                !add_as112_default(zones, cfg, "8.b.d.0.1.0.0.2.ip6.arpa.")) {
                log_err("out of memory adding default zone");
                return 0;
        }
        return 1;
}

/** setup parent pointers, so that a lookup can be done for closest match */
static void
init_parents(struct local_zones* zones)
{
        struct local_zone* node, *prev = NULL, *p;
        int m;
        lock_rw_wrlock(&zones->lock);
        RBTREE_FOR(node, struct local_zone*, &zones->ztree) {
                lock_rw_wrlock(&node->lock);
                node->parent = NULL;
                if(!prev || prev->dclass != node->dclass) {
                        prev = node;
                        lock_rw_unlock(&node->lock);
                        continue;
                }
                (void)dname_lab_cmp(prev->name, prev->namelabs, node->name,
                        node->namelabs, &m); /* we know prev is smaller */
                /* sort order like: . com. bla.com. zwb.com. net. */
                /* find the previous, or parent-parent-parent */
                for(p = prev; p; p = p->parent)
                        /* looking for name with few labels, a parent */
                        if(p->namelabs <= m) {
                                /* ==: since prev matched m, this is closest*/
                                /* <: prev matches more, but is not a parent,
                                 * this one is a (grand)parent */
                                node->parent = p;
                                break;
                        }
                prev = node;
                lock_rw_unlock(&node->lock);
        }
        lock_rw_unlock(&zones->lock);
}

/** enter implicit transparent zone for local-data: without local-zone: */
static int
lz_setup_implicit(struct local_zones* zones, struct config_file* cfg)
{
        /* walk over all items that have no parent zone and find
         * the name that covers them all (could be the root) and
         * add that as a transparent zone */
        struct config_strlist* p;
        int have_name = 0;
        int have_other_classes = 0;
        uint16_t dclass = 0;
        uint8_t* nm = 0;
        size_t nmlen = 0;
        int nmlabs = 0;
        int match = 0; /* number of labels match count */

        init_parents(zones); /* to enable local_zones_lookup() */
        for(p = cfg->local_data; p; p = p->next) {
                uint8_t* rr_name;
                uint16_t rr_class;
                size_t len;
                int labs;
                if(!get_rr_nameclass(p->str, &rr_name, &rr_class)) {
                        log_err("Bad local-data RR %s", p->str);
                        return 0;
                }
                labs = dname_count_size_labels(rr_name, &len);
                lock_rw_rdlock(&zones->lock);
                if(!local_zones_lookup(zones, rr_name, len, labs, rr_class)) {
                        if(!have_name) {
                                dclass = rr_class;
                                nm = rr_name;
                                nmlen = len;
                                nmlabs = labs;
                                match = labs;
                                have_name = 1;
                        } else {
                                int m;
                                if(rr_class != dclass) {
                                        /* process other classes later */
                                        free(rr_name);
                                        have_other_classes = 1;
                                        lock_rw_unlock(&zones->lock);
                                        continue;
                                }
                                /* find smallest shared topdomain */
                                (void)dname_lab_cmp(nm, nmlabs, 
                                        rr_name, labs, &m);
                                free(rr_name);
                                if(m < match)
                                        match = m;
                        }
                } else free(rr_name);
                lock_rw_unlock(&zones->lock);
        }
        if(have_name) {
                uint8_t* n2;
                struct local_zone* z;
                /* allocate zone of smallest shared topdomain to contain em */
                n2 = nm;
                dname_remove_labels(&n2, &nmlen, nmlabs - match);
                n2 = memdup(n2, nmlen);
                free(nm);
                if(!n2) {
                        log_err("out of memory");
                        return 0;
                }
                log_nametypeclass(VERB_ALGO, "implicit transparent local-zone", 
                        n2, 0, dclass);
                if(!(z=lz_enter_zone_dname(zones, n2, nmlen, match, 
                        local_zone_transparent, dclass))) {
                        return 0;
                }
                lock_rw_unlock(&z->lock);
        }
        if(have_other_classes) { 
                /* restart to setup other class */
                return lz_setup_implicit(zones, cfg);
        }
        return 1;
}

/** enter auth data */
static int
lz_enter_data(struct local_zones* zones, struct config_file* cfg)
{
        struct config_strlist* p;
        for(p = cfg->local_data; p; p = p->next) {
                if(!lz_enter_rr_str(zones, p->str))
                        return 0;
        }
        return 1;
}

/** free memory from config */
static void
lz_freeup_cfg(struct config_file* cfg)
{
        config_deldblstrlist(cfg->local_zones);
        cfg->local_zones = NULL;
        config_delstrlist(cfg->local_zones_nodefault);
        cfg->local_zones_nodefault = NULL;
        config_delstrlist(cfg->local_data);
        cfg->local_data = NULL;
}

int 
local_zones_apply_cfg(struct local_zones* zones, struct config_file* cfg)
{
        /* create zones from zone statements. */
        if(!lz_enter_zones(zones, cfg)) {
                return 0;
        }
        /* apply default zones+content (unless disabled, or overridden) */
        if(!lz_enter_defaults(zones, cfg)) {
                return 0;
        }
        /* create implicit transparent zone from data. */
        if(!lz_setup_implicit(zones, cfg)) {
                return 0;
        }

        /* setup parent ptrs for lookup during data entry */
        init_parents(zones);
        /* insert local data */
        if(!lz_enter_data(zones, cfg)) {
                return 0;
        }
        /* freeup memory from cfg struct. */
        lz_freeup_cfg(cfg);
        return 1;
}

struct local_zone* 
local_zones_lookup(struct local_zones* zones,
        uint8_t* name, size_t len, int labs, uint16_t dclass)
{
        rbnode_t* res = NULL;
        struct local_zone *result;
        struct local_zone key;
        key.node.key = &key;
        key.dclass = dclass;
        key.name = name;
        key.namelen = len;
        key.namelabs = labs;
        if(rbtree_find_less_equal(&zones->ztree, &key, &res)) {
                /* exact */
                return (struct local_zone*)res;
        } else {
                /* smaller element (or no element) */
                int m;
                result = (struct local_zone*)res;
                if(!result || result->dclass != dclass)
                        return NULL;
                /* count number of labels matched */
                (void)dname_lab_cmp(result->name, result->namelabs, key.name,
                        key.namelabs, &m);
                while(result) { /* go up until qname is subdomain of zone */
                        if(result->namelabs <= m)
                                break;
                        result = result->parent;
                }
                return result;
        }
}

struct local_zone* 
local_zones_find(struct local_zones* zones,
        uint8_t* name, size_t len, int labs, uint16_t dclass)
{
        struct local_zone key;
        key.node.key = &key;
        key.dclass = dclass;
        key.name = name;
        key.namelen = len;
        key.namelabs = labs;
        /* exact */
        return (struct local_zone*)rbtree_search(&zones->ztree, &key);
}

/** print all RRsets in local zone */
static void 
local_zone_out(struct local_zone* z)
{
        struct local_data* d;
        struct local_rrset* p;
        RBTREE_FOR(d, struct local_data*, &z->data) {
                for(p = d->rrsets; p; p = p->next) {
                        log_nametypeclass(0, "rrset", d->name, 
                                ntohs(p->rrset->rk.type),
                                ntohs(p->rrset->rk.rrset_class));
                }
        }
}

void local_zones_print(struct local_zones* zones)
{
        struct local_zone* z;
        lock_rw_rdlock(&zones->lock);
        log_info("number of auth zones %u", (unsigned)zones->ztree.count);
        RBTREE_FOR(z, struct local_zone*, &zones->ztree) {
                lock_rw_rdlock(&z->lock);
                switch(z->type) {
                case local_zone_deny:
                        log_nametypeclass(0, "deny zone", 
                                z->name, 0, z->dclass);
                        break;
                case local_zone_refuse:
                        log_nametypeclass(0, "refuse zone", 
                                z->name, 0, z->dclass);
                        break;
                case local_zone_redirect:
                        log_nametypeclass(0, "redirect zone", 
                                z->name, 0, z->dclass);
                        break;
                case local_zone_transparent:
                        log_nametypeclass(0, "transparent zone", 
                                z->name, 0, z->dclass);
                        break;
                case local_zone_typetransparent:
                        log_nametypeclass(0, "typetransparent zone", 
                                z->name, 0, z->dclass);
                        break;
                case local_zone_static:
                        log_nametypeclass(0, "static zone", 
                                z->name, 0, z->dclass);
                        break;
                default:
                        log_nametypeclass(0, "badtyped zone", 
                                z->name, 0, z->dclass);
                        break;
                }
                local_zone_out(z);
                lock_rw_unlock(&z->lock);
        }
        lock_rw_unlock(&zones->lock);
}

/** encode answer consisting of 1 rrset */
static int
local_encode(struct query_info* qinfo, struct edns_data* edns, 
        sldns_buffer* buf, struct regional* temp, 
        struct ub_packed_rrset_key* rrset, int ansec, int rcode)
{
        struct reply_info rep;
        uint16_t udpsize;
        /* make answer with time=0 for fixed TTL values */
        memset(&rep, 0, sizeof(rep));
        rep.flags = (uint16_t)((BIT_QR | BIT_AA | BIT_RA) | rcode);
        rep.qdcount = 1;
        if(ansec)
                rep.an_numrrsets = 1;
        else    rep.ns_numrrsets = 1;
        rep.rrset_count = 1;
        rep.rrsets = &rrset;
        udpsize = edns->udp_size;
        edns->edns_version = EDNS_ADVERTISED_VERSION;
        edns->udp_size = EDNS_ADVERTISED_SIZE;
        edns->ext_rcode = 0;
        edns->bits &= EDNS_DO;
        if(!reply_info_answer_encode(qinfo, &rep, 
                *(uint16_t*)sldns_buffer_begin(buf),
                sldns_buffer_read_u16_at(buf, 2),
                buf, 0, 0, temp, udpsize, edns, 
                (int)(edns->bits&EDNS_DO), 0))
                error_encode(buf, (LDNS_RCODE_SERVFAIL|BIT_AA), qinfo,
                        *(uint16_t*)sldns_buffer_begin(buf),
                       sldns_buffer_read_u16_at(buf, 2), edns);
        return 1;
}

/** answer local data match */
static int
local_data_answer(struct local_zone* z, struct query_info* qinfo,
        struct edns_data* edns, sldns_buffer* buf, struct regional* temp,
        int labs, struct local_data** ldp)
{
        struct local_data key;
        struct local_data* ld;
        struct local_rrset* lr;
        key.node.key = &key;
        key.name = qinfo->qname;
        key.namelen = qinfo->qname_len;
        key.namelabs = labs;
        if(z->type == local_zone_redirect) {
                key.name = z->name;
                key.namelen = z->namelen;
                key.namelabs = z->namelabs;
        }
        ld = (struct local_data*)rbtree_search(&z->data, &key.node);
        *ldp = ld;
        if(!ld) {
                return 0;
        }
        lr = local_data_find_type(ld, qinfo->qtype);
        if(!lr)
                return 0;
        if(z->type == local_zone_redirect) {
                /* convert rrset name to query name; like a wildcard */
                struct ub_packed_rrset_key r = *lr->rrset;
                r.rk.dname = qinfo->qname;
                r.rk.dname_len = qinfo->qname_len;
                return local_encode(qinfo, edns, buf, temp, &r, 1, 
                        LDNS_RCODE_NOERROR);
        }
        return local_encode(qinfo, edns, buf, temp, lr->rrset, 1, 
                LDNS_RCODE_NOERROR);
}

/** 
 * answer in case where no exact match is found 
 * @param z: zone for query
 * @param qinfo: query
 * @param edns: edns from query
 * @param buf: buffer for answer.
 * @param temp: temp region for encoding
 * @param ld: local data, if NULL, no such name exists in localdata.
 * @return 1 if a reply is to be sent, 0 if not.
 */
static int
lz_zone_answer(struct local_zone* z, struct query_info* qinfo,
        struct edns_data* edns, sldns_buffer* buf, struct regional* temp,
        struct local_data* ld)
{
        if(z->type == local_zone_deny) {
                /** no reply at all, signal caller by clearing buffer. */
                sldns_buffer_clear(buf);
                sldns_buffer_flip(buf);
                return 1;
        } else if(z->type == local_zone_refuse) {
                error_encode(buf, (LDNS_RCODE_REFUSED|BIT_AA), qinfo,
                        *(uint16_t*)sldns_buffer_begin(buf),
                       sldns_buffer_read_u16_at(buf, 2), edns);
                return 1;
        } else if(z->type == local_zone_static ||
                z->type == local_zone_redirect) {
                /* for static, reply nodata or nxdomain
                 * for redirect, reply nodata */
                /* no additional section processing,
                 * cname, dname or wildcard processing,
                 * or using closest match for NSEC.
                 * or using closest match for returning delegation downwards
                 */
                int rcode = ld?LDNS_RCODE_NOERROR:LDNS_RCODE_NXDOMAIN;
                if(z->soa)
                        return local_encode(qinfo, edns, buf, temp, 
                                z->soa, 0, rcode);
                error_encode(buf, (rcode|BIT_AA), qinfo, 
                        *(uint16_t*)sldns_buffer_begin(buf), 
                        sldns_buffer_read_u16_at(buf, 2), edns);
                return 1;
        } else if(z->type == local_zone_typetransparent) {
                /* no NODATA or NXDOMAINS for this zone type */
                return 0;
        }
        /* else z->type == local_zone_transparent */

        /* if the zone is transparent and the name exists, but the type
         * does not, then we should make this noerror/nodata */
        if(ld && ld->rrsets) {
                int rcode = LDNS_RCODE_NOERROR;
                if(z->soa)
                        return local_encode(qinfo, edns, buf, temp, 
                                z->soa, 0, rcode);
                error_encode(buf, (rcode|BIT_AA), qinfo, 
                        *(uint16_t*)sldns_buffer_begin(buf), 
                        sldns_buffer_read_u16_at(buf, 2), edns);
                return 1;
        }

        /* stop here, and resolve further on */
        return 0;
}

int 
local_zones_answer(struct local_zones* zones, struct query_info* qinfo,
        struct edns_data* edns, sldns_buffer* buf, struct regional* temp)
{
        /* see if query is covered by a zone,
         *      if so:  - try to match (exact) local data 
         *              - look at zone type for negative response. */
        int labs = dname_count_labels(qinfo->qname);
        struct local_data* ld;
        struct local_zone* z;
        int r;
        lock_rw_rdlock(&zones->lock);
        z = local_zones_lookup(zones, qinfo->qname,
                qinfo->qname_len, labs, qinfo->qclass);
        if(!z) {
                lock_rw_unlock(&zones->lock);
                return 0;
        }
        lock_rw_rdlock(&z->lock);
        lock_rw_unlock(&zones->lock);

        if(local_data_answer(z, qinfo, edns, buf, temp, labs, &ld)) {
                lock_rw_unlock(&z->lock);
                return 1;
        }
        r = lz_zone_answer(z, qinfo, edns, buf, temp, ld);
        lock_rw_unlock(&z->lock);
        return r;
}

const char* local_zone_type2str(enum localzone_type t)
{
        switch(t) {
                case local_zone_deny: return "deny";
                case local_zone_refuse: return "refuse";
                case local_zone_redirect: return "redirect";
                case local_zone_transparent: return "transparent";
                case local_zone_typetransparent: return "typetransparent";
                case local_zone_static: return "static";
                case local_zone_nodefault: return "nodefault";
        }
        return "badtyped"; 
}

int local_zone_str2type(const char* type, enum localzone_type* t)
{
        if(strcmp(type, "deny") == 0)
                *t = local_zone_deny;
        else if(strcmp(type, "refuse") == 0)
                *t = local_zone_refuse;
        else if(strcmp(type, "static") == 0)
                *t = local_zone_static;
        else if(strcmp(type, "transparent") == 0)
                *t = local_zone_transparent;
        else if(strcmp(type, "typetransparent") == 0)
                *t = local_zone_typetransparent;
        else if(strcmp(type, "redirect") == 0)
                *t = local_zone_redirect;
        else return 0;
        return 1;
}

/** iterate over the kiddies of the given name and set their parent ptr */
static void
set_kiddo_parents(struct local_zone* z, struct local_zone* match, 
        struct local_zone* newp)
{
        /* both zones and z are locked already */
        /* in the sorted rbtree, the kiddies of z are located after z */
        /* z must be present in the tree */
        struct local_zone* p = z;
        p = (struct local_zone*)rbtree_next(&p->node);
        while(p!=(struct local_zone*)RBTREE_NULL &&
                p->dclass == z->dclass && dname_strict_subdomain(p->name,
                p->namelabs, z->name, z->namelabs)) {
                /* update parent ptr */
                /* only when matches with existing parent pointer, so that
                 * deeper child structures are not touched, i.e.
                 * update of x, and a.x, b.x, f.b.x, g.b.x, c.x, y
                 * gets to update a.x, b.x and c.x */
                lock_rw_wrlock(&p->lock);
                if(p->parent == match)
                        p->parent = newp;
                lock_rw_unlock(&p->lock);
                p = (struct local_zone*)rbtree_next(&p->node);
        }
}

struct local_zone* local_zones_add_zone(struct local_zones* zones,
        uint8_t* name, size_t len, int labs, uint16_t dclass,
        enum localzone_type tp)
{
        /* create */
        struct local_zone* z = local_zone_create(name, len, labs, tp, dclass);
        if(!z) return NULL;
        lock_rw_wrlock(&z->lock);

        /* find the closest parent */
        z->parent = local_zones_find(zones, name, len, labs, dclass);

        /* insert into the tree */
        if(!rbtree_insert(&zones->ztree, &z->node)) {
                /* duplicate entry! */
                lock_rw_unlock(&z->lock);
                local_zone_delete(z);
                log_err("internal: duplicate entry in local_zones_add_zone");
                return NULL;
        }

        /* set parent pointers right */
        set_kiddo_parents(z, z->parent, z);

        lock_rw_unlock(&z->lock);
        return z;
}

void local_zones_del_zone(struct local_zones* zones, struct local_zone* z)
{
        /* fix up parents in tree */
        lock_rw_wrlock(&z->lock);
        set_kiddo_parents(z, z, z->parent);

        /* remove from tree */
        (void)rbtree_delete(&zones->ztree, z);

        /* delete the zone */
        lock_rw_unlock(&z->lock);
        local_zone_delete(z);
}

int
local_zones_add_RR(struct local_zones* zones, const char* rr)
{
        uint8_t* rr_name;
        uint16_t rr_class;
        size_t len;
        int labs;
        struct local_zone* z;
        int r;
        if(!get_rr_nameclass(rr, &rr_name, &rr_class)) {
                return 0;
        }
        labs = dname_count_size_labels(rr_name, &len);
        /* could first try readlock then get writelock if zone does not exist,
         * but we do not add enough RRs (from multiple threads) to optimize */
        lock_rw_wrlock(&zones->lock);
        z = local_zones_lookup(zones, rr_name, len, labs, rr_class);
        if(!z) {
                z = local_zones_add_zone(zones, rr_name, len, labs, rr_class,
                        local_zone_transparent);
                if(!z) {
                        lock_rw_unlock(&zones->lock);
                        return 0;
                }
        } else {
                free(rr_name);
        }
        lock_rw_wrlock(&z->lock);
        lock_rw_unlock(&zones->lock);
        r = lz_enter_rr_into_zone(z, rr);
        lock_rw_unlock(&z->lock);
        return r;
}

/** returns true if the node is terminal so no deeper domain names exist */
static int
is_terminal(struct local_data* d)
{
        /* for empty nonterminals, the deeper domain names are sorted
         * right after them, so simply check the next name in the tree 
         */
        struct local_data* n = (struct local_data*)rbtree_next(&d->node);
        if(n == (struct local_data*)RBTREE_NULL)
                return 1; /* last in tree, no deeper node */
        if(dname_strict_subdomain(n->name, n->namelabs, d->name, d->namelabs))
                return 0; /* there is a deeper node */
        return 1;
}

/** delete empty terminals from tree when final data is deleted */
static void 
del_empty_term(struct local_zone* z, struct local_data* d, 
        uint8_t* name, size_t len, int labs)
{
        while(d && d->rrsets == NULL && is_terminal(d)) {
                /* is this empty nonterminal? delete */
                /* note, no memory recycling in zone region */
                (void)rbtree_delete(&z->data, d);

                /* go up and to the next label */
                if(dname_is_root(name))
                        return;
                dname_remove_label(&name, &len);
                labs--;
                d = lz_find_node(z, name, len, labs);
        }
}

void local_zones_del_data(struct local_zones* zones, 
        uint8_t* name, size_t len, int labs, uint16_t dclass)
{
        /* find zone */
        struct local_zone* z;
        struct local_data* d;
        lock_rw_rdlock(&zones->lock);
        z = local_zones_lookup(zones, name, len, labs, dclass);
        if(!z) {
                /* no such zone, we're done */
                lock_rw_unlock(&zones->lock);
                return;
        }
        lock_rw_wrlock(&z->lock);
        lock_rw_unlock(&zones->lock);

        /* find the domain */
        d = lz_find_node(z, name, len, labs);
        if(d) {
                /* no memory recycling for zone deletions ... */
                d->rrsets = NULL;
                /* did we delete the soa record ? */
                if(query_dname_compare(d->name, z->name) == 0)
                        z->soa = NULL;

                /* cleanup the empty nonterminals for this name */
                del_empty_term(z, d, name, len, labs);
        }

        lock_rw_unlock(&z->lock);
}