unbound/services/localzone.c

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/*
* 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 REGENTS 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 "util/regional.h"
#include "util/config_file.h"
#include "util/data/dname.h"
#include "util/data/packed_rrset.h"
#include "util/net_help.h"
struct local_zones*
local_zones_create()
{
struct local_zones* zones = (struct local_zones*)calloc(1,
sizeof(*zones));
if(!zones)
return NULL;
rbtree_init(&zones->ztree, &local_zone_cmp);
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;
/* 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;
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 */
static int
parse_dname(const char* str, uint8_t** res, size_t* len, int* labs)
{
ldns_rdf* rdf;
*res = NULL;
*len = 0;
*labs = 0;
rdf = ldns_dname_new_frm_str(str);
if(!rdf) {
log_err("cannot parse name %s", str);
return 0;
}
*res = memdup(ldns_rdf_data(rdf), ldns_rdf_size(rdf));
ldns_rdf_deep_free(rdf);
if(!*res) {
log_err("out of memory");
return 0;
}
*labs = dname_count_size_labels(*res, len);
return 1;
}
/** enter a new zone with allocated dname */
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 dclass)
{
struct local_zone* z = (struct local_zone*)calloc(1, sizeof(*z));
if(!z) {
log_err("out of memory");
return NULL;
}
z->node.key = z;
z->dclass = dclass;
z->type = t;
z->name = nm;
z->namelen = len;
z->namelabs = labs;
z->region = regional_create();
if(!z->region) {
log_err("out of memory");
free(z);
return NULL;
}
rbtree_init(&z->data, &local_data_cmp);
/* add to rbtree */
if(!rbtree_insert(&zones->ztree, &z->node)) {
log_warn("duplicate local-zone");
local_zone_delete(z);
return NULL;
}
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(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, "redirect") == 0)
t = local_zone_redirect;
else {
log_err("bad lz_enter_zone type %s %s", name, type);
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, uint32_t* ttl, ldns_buffer* rdata)
{
ldns_rr* rr = NULL;
ldns_status status = ldns_rr_new_frm_str(&rr, str, 3600, NULL, NULL);
if(status != LDNS_STATUS_OK) {
log_err("error parsing local-data '%s': %s",
str, ldns_get_errorstr_by_id(status));
ldns_rr_free(rr);
return 0;
}
*nm = memdup(ldns_rdf_data(ldns_rr_owner(rr)),
ldns_rdf_size(ldns_rr_owner(rr)));
if(!*nm) {
log_err("out of memory");
ldns_rr_free(rr);
return 0;
}
*dclass = ldns_rr_get_class(rr);
*type = ldns_rr_get_type(rr);
*ttl = (uint32_t)ldns_rr_ttl(rr);
ldns_buffer_clear(rdata);
status = ldns_rr_rdata2buffer_wire(rdata, rr);
ldns_rr_free(rr);
if(status != LDNS_STATUS_OK) {
log_err("error converting RR '%s' to wireformat: %s",
str, ldns_get_errorstr_by_id(status));
return 0;
}
ldns_buffer_flip(rdata);
ldns_buffer_write_u16_at(rdata, 0, ldns_buffer_limit(rdata) - 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)
{
ldns_rr* rr = NULL;
ldns_status status = ldns_rr_new_frm_str(&rr, str, 3600, NULL, NULL);
if(status != LDNS_STATUS_OK) {
log_err("error parsing local-data '%s': %s",
str, ldns_get_errorstr_by_id(status));
ldns_rr_free(rr);
return 0;
}
*nm = memdup(ldns_rdf_data(ldns_rr_owner(rr)),
ldns_rdf_size(ldns_rr_owner(rr)));
*dclass = ldns_rr_get_class(rr);
ldns_rr_free(rr);
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.
*/
struct local_rrset*
local_data_find_type(struct local_data* data, uint16_t type)
{
struct local_rrset* p;
for(p = data->rrsets; p; p = p->next) {
if(ntohs(p->rrset->rk.type) == type)
return p;
}
return NULL;
}
/** check for RR duplicates */
static int
rr_is_duplicate(struct packed_rrset_data* pd, ldns_buffer* buf)
{
size_t i;
for(i=0; i<pd->count; i++) {
if(ldns_buffer_limit(buf) == pd->rr_len[i] &&
memcmp(ldns_buffer_begin(buf), pd->rr_data[i],
ldns_buffer_limit(buf)) == 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,
ldns_buffer* buf, uint32_t ttl)
{
size_t* oldlen = pd->rr_len;
uint32_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] = ldns_buffer_limit(buf);
pd->rr_ttl[0] = ttl;
pd->rr_data[0] = regional_alloc_init(region,
ldns_buffer_begin(buf), ldns_buffer_limit(buf));
if(!pd->rr_data[0]) {
log_err("out of memory");
return 0;
}
return 1;
}
/** enter data RR into auth zone */
static int
lz_enter_rr_into_zone(struct local_zone* z, ldns_buffer* buf,
const char* rrstr)
{
struct local_data key;
struct local_data* node;
struct local_rrset* rrset;
struct packed_rrset_data* pd;
uint16_t rrtype, rrclass;
uint32_t ttl;
if(!get_rr_content(rrstr, &key.name, &rrtype, &rrclass, &ttl, buf)) {
log_err("bad local-data: %s", rrstr);
return 0;
}
log_assert(z->dclass == rrclass);
key.node.key = &key;
key.namelabs = dname_count_size_labels(key.name, &key.namelen);
node = (struct local_data*)rbtree_search(&z->data, &key.node);
if(!node) {
/* create a domain name to store rr. */
node = (struct local_data*)regional_alloc_zero(z->region,
sizeof(*node));
if(!node) {
log_err("out of memory adding local data");
return 0;
}
node->node.key = &node;
node->name = regional_alloc_init(z->region, key.name,
key.namelen);
if(!node->name) {
log_err("out of memory");
return 0;
}
node->namelen = key.namelen;
node->namelabs = key.namelabs;
if(!rbtree_insert(&z->data, &node->node)) {
log_assert(0); /* duplicate name */
}
}
free(key.name);
log_assert(node);
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, buf)) {
verbose(VERB_ALGO, "ignoring duplicate RR: %s", rrstr);
return 1;
}
return insert_rr(z->region, pd, buf, 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, ldns_buffer* buf)
{
uint8_t* rr_name;
uint16_t rr_class;
size_t len;
int labs;
struct local_zone* z;
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);
z = local_zones_lookup(zones, rr_name, len, labs, rr_class);
if(!z)
fatal_exit("internal error: no zone for rr %s", rr);
free(rr_name);
return lz_enter_rr_into_zone(z, buf, rr);
}
/** parse local-zone: statements */
static int
lz_enter_zones(struct local_zones* zones, struct config_file* cfg)
{
struct config_str2list* p;
for(p = cfg->local_zones; p; p = p->next) {
if(!lz_enter_zone(zones, p->str, p->str2, LDNS_RR_CLASS_IN))
return 0;
}
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;
}
if(rbtree_search(&zones->ztree, &z.node)) {
free(z.name);
return 1;
}
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;
for(p = cfg->local_zones_nodefault; p; p = p->next) {
/* compare zone name, lowercase */
if(strcasecmp(p->str, name) == 0)
return 1;
}
return 0;
}
/** enter default zones */
static int
lz_enter_defaults(struct local_zones* zones, struct config_file* cfg,
ldns_buffer* buf)
{
struct local_zone* z;
/* 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, buf,
"localhost. 10800 IN NS localhost.") ||
!lz_enter_rr_into_zone(z, buf,
"localhost. 10800 IN SOA localhost. nobody.invalid. "
"1 3600 1200 604800 10800") ||
!lz_enter_rr_into_zone(z, buf,
"localhost. 10800 IN A 127.0.0.1") ||
!lz_enter_rr_into_zone(z, buf,
"localhost. 10800 IN AAAA ::1")) {
log_err("out of memory adding default zone");
return 0;
}
}
/* @@@ TODO other zones */
return 0;
}
/** 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;
RBTREE_FOR(node, struct local_zone*, &zones->ztree) {
node->parent = NULL;
if(!prev || prev->dclass != node->dclass) {
prev = node;
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;
}
}
/** 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);
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 */
have_other_classes = 1;
continue;
}
/* find smallest shared topdomain */
(void)dname_lab_cmp(nm, nmlabs,
rr_name, labs, &m);
if(m < match)
match = m;
}
}
free(rr_name);
}
if(have_name) {
uint8_t* n2;
/* 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;
}
if(!lz_enter_zone_dname(zones, n2, nmlen, match,
local_zone_transparent, dclass)) {
return 0;
}
}
if(have_other_classes) {
/* restart to setup other class */
return lz_setup_implicit(zones, cfg);
}
return 0;
}
/** enter auth data */
static int
lz_enter_data(struct local_zones* zones, struct config_file* cfg,
ldns_buffer* buf)
{
struct config_strlist* p;
for(p = cfg->local_data; p; p = p->next) {
if(!lz_enter_rr_str(zones, p->str, buf))
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)
{
ldns_buffer* buf = ldns_buffer_new(65535);
if(!buf) fatal_exit("cannot create temporary buffer");
/* create zones from zone statements. */
if(!lz_enter_zones(zones, cfg)) {
ldns_buffer_free(buf);
return 0;
}
/* apply default zones+content (unless disabled, or overridden) */
if(!lz_enter_defaults(zones, cfg, buf)) {
ldns_buffer_free(buf);
return 0;
}
/* create implicit transparent zone from data. */
if(!lz_setup_implicit(zones, cfg)) {
ldns_buffer_free(buf);
return 0;
}
/* setup parent ptrs for lookup during data entry */
init_parents(zones);
/* insert local data */
if(!lz_enter_data(zones, cfg, buf)) {
ldns_buffer_free(buf);
return 0;
}
/* freeup memory from cfg struct. */
lz_freeup_cfg(cfg);
ldns_buffer_free(buf);
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;
}
}
/** 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;
log_info("number of auth zones %u", (unsigned)zones->ztree.count);
RBTREE_FOR(z, struct local_zone*, &zones->ztree) {
switch(z->type) {
case local_zone_deny:
log_nametypeclass(0, "deny zone",
z->name, 0, z->dclass);
case local_zone_refuse:
log_nametypeclass(0, "refuse zone",
z->name, 0, z->dclass);
case local_zone_redirect:
log_nametypeclass(0, "redirect zone",
z->name, 0, z->dclass);
case local_zone_transparent:
log_nametypeclass(0, "transparent zone",
z->name, 0, z->dclass);
case local_zone_static:
log_nametypeclass(0, "static zone",
z->name, 0, z->dclass);
default:
log_nametypeclass(0, "badtyped zone",
z->name, 0, z->dclass);
}
local_zone_out(z);
}
}