wownero/external/unbound/iterator/iter_fwd.c
Erik de Castro Lopo a85b5759f3 Upgrade unbound library
These files were pulled from the 1.6.3 release tarball.

This new version builds against OpenSSL version 1.1 which will be
the default in the new Debian Stable which is due to be released
RealSoonNow (tm).
2017-06-17 23:04:00 +10:00

509 lines
13 KiB
C

/*
* iterator/iter_fwd.c - iterative resolver module forward zones.
*
* 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 assist the iterator module.
* Keep track of forward zones and config settings.
*/
#include "config.h"
#include "iterator/iter_fwd.h"
#include "iterator/iter_delegpt.h"
#include "util/log.h"
#include "util/config_file.h"
#include "util/net_help.h"
#include "util/data/dname.h"
#include "sldns/rrdef.h"
#include "sldns/str2wire.h"
int
fwd_cmp(const void* k1, const void* k2)
{
int m;
struct iter_forward_zone* n1 = (struct iter_forward_zone*)k1;
struct iter_forward_zone* n2 = (struct iter_forward_zone*)k2;
if(n1->dclass != n2->dclass) {
if(n1->dclass < n2->dclass)
return -1;
return 1;
}
return dname_lab_cmp(n1->name, n1->namelabs, n2->name, n2->namelabs,
&m);
}
struct iter_forwards*
forwards_create(void)
{
struct iter_forwards* fwd = (struct iter_forwards*)calloc(1,
sizeof(struct iter_forwards));
if(!fwd)
return NULL;
return fwd;
}
static void fwd_zone_free(struct iter_forward_zone* n)
{
if(!n) return;
delegpt_free_mlc(n->dp);
free(n->name);
free(n);
}
static void delfwdnode(rbnode_type* n, void* ATTR_UNUSED(arg))
{
struct iter_forward_zone* node = (struct iter_forward_zone*)n;
fwd_zone_free(node);
}
static void fwd_del_tree(struct iter_forwards* fwd)
{
if(fwd->tree)
traverse_postorder(fwd->tree, &delfwdnode, NULL);
free(fwd->tree);
}
void
forwards_delete(struct iter_forwards* fwd)
{
if(!fwd)
return;
fwd_del_tree(fwd);
free(fwd);
}
/** insert info into forward structure */
static int
forwards_insert_data(struct iter_forwards* fwd, uint16_t c, uint8_t* nm,
size_t nmlen, int nmlabs, struct delegpt* dp)
{
struct iter_forward_zone* node = (struct iter_forward_zone*)malloc(
sizeof(struct iter_forward_zone));
if(!node) {
delegpt_free_mlc(dp);
return 0;
}
node->node.key = node;
node->dclass = c;
node->name = memdup(nm, nmlen);
if(!node->name) {
delegpt_free_mlc(dp);
free(node);
return 0;
}
node->namelen = nmlen;
node->namelabs = nmlabs;
node->dp = dp;
if(!rbtree_insert(fwd->tree, &node->node)) {
char buf[257];
dname_str(nm, buf);
log_err("duplicate forward zone %s ignored.", buf);
delegpt_free_mlc(dp);
free(node->name);
free(node);
}
return 1;
}
/** insert new info into forward structure given dp */
static int
forwards_insert(struct iter_forwards* fwd, uint16_t c, struct delegpt* dp)
{
return forwards_insert_data(fwd, c, dp->name, dp->namelen,
dp->namelabs, dp);
}
/** initialise parent pointers in the tree */
static void
fwd_init_parents(struct iter_forwards* fwd)
{
struct iter_forward_zone* node, *prev = NULL, *p;
int m;
RBTREE_FOR(node, struct iter_forward_zone*, fwd->tree) {
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;
}
}
/** set zone name */
static struct delegpt*
read_fwds_name(struct config_stub* s)
{
struct delegpt* dp;
uint8_t* dname;
size_t dname_len;
if(!s->name) {
log_err("forward zone without a name (use name \".\" to forward everything)");
return NULL;
}
dname = sldns_str2wire_dname(s->name, &dname_len);
if(!dname) {
log_err("cannot parse forward zone name %s", s->name);
return NULL;
}
if(!(dp=delegpt_create_mlc(dname))) {
free(dname);
log_err("out of memory");
return NULL;
}
free(dname);
return dp;
}
/** set fwd host names */
static int
read_fwds_host(struct config_stub* s, struct delegpt* dp)
{
struct config_strlist* p;
uint8_t* dname;
size_t dname_len;
for(p = s->hosts; p; p = p->next) {
log_assert(p->str);
dname = sldns_str2wire_dname(p->str, &dname_len);
if(!dname) {
log_err("cannot parse forward %s server name: '%s'",
s->name, p->str);
return 0;
}
if(!delegpt_add_ns_mlc(dp, dname, 0)) {
free(dname);
log_err("out of memory");
return 0;
}
free(dname);
}
return 1;
}
/** set fwd server addresses */
static int
read_fwds_addr(struct config_stub* s, struct delegpt* dp)
{
struct config_strlist* p;
struct sockaddr_storage addr;
socklen_t addrlen;
for(p = s->addrs; p; p = p->next) {
log_assert(p->str);
if(!extstrtoaddr(p->str, &addr, &addrlen)) {
log_err("cannot parse forward %s ip address: '%s'",
s->name, p->str);
return 0;
}
if(!delegpt_add_addr_mlc(dp, &addr, addrlen, 0, 0)) {
log_err("out of memory");
return 0;
}
}
return 1;
}
/** read forwards config */
static int
read_forwards(struct iter_forwards* fwd, struct config_file* cfg)
{
struct config_stub* s;
for(s = cfg->forwards; s; s = s->next) {
struct delegpt* dp;
if(!(dp=read_fwds_name(s)))
return 0;
if(!read_fwds_host(s, dp) || !read_fwds_addr(s, dp)) {
delegpt_free_mlc(dp);
return 0;
}
/* set flag that parent side NS information is included.
* Asking a (higher up) server on the internet is not useful */
/* the flag is turned off for 'forward-first' so that the
* last resort will ask for parent-side NS record and thus
* fallback to the internet name servers on a failure */
dp->has_parent_side_NS = (uint8_t)!s->isfirst;
/* use SSL for queries to this forwarder */
dp->ssl_upstream = (uint8_t)s->ssl_upstream;
verbose(VERB_QUERY, "Forward zone server list:");
delegpt_log(VERB_QUERY, dp);
if(!forwards_insert(fwd, LDNS_RR_CLASS_IN, dp))
return 0;
}
return 1;
}
/** insert a stub hole (if necessary) for stub name */
static int
fwd_add_stub_hole(struct iter_forwards* fwd, uint16_t c, uint8_t* nm)
{
struct iter_forward_zone key;
key.node.key = &key;
key.dclass = c;
key.name = nm;
key.namelabs = dname_count_size_labels(key.name, &key.namelen);
return forwards_insert_data(fwd, key.dclass, key.name,
key.namelen, key.namelabs, NULL);
}
/** make NULL entries for stubs */
static int
make_stub_holes(struct iter_forwards* fwd, struct config_file* cfg)
{
struct config_stub* s;
uint8_t* dname;
size_t dname_len;
for(s = cfg->stubs; s; s = s->next) {
if(!s->name) continue;
dname = sldns_str2wire_dname(s->name, &dname_len);
if(!dname) {
log_err("cannot parse stub name '%s'", s->name);
return 0;
}
if(!fwd_add_stub_hole(fwd, LDNS_RR_CLASS_IN, dname)) {
free(dname);
log_err("out of memory");
return 0;
}
free(dname);
}
return 1;
}
int
forwards_apply_cfg(struct iter_forwards* fwd, struct config_file* cfg)
{
fwd_del_tree(fwd);
fwd->tree = rbtree_create(fwd_cmp);
if(!fwd->tree)
return 0;
/* read forward zones */
if(!read_forwards(fwd, cfg))
return 0;
if(!make_stub_holes(fwd, cfg))
return 0;
fwd_init_parents(fwd);
return 1;
}
struct delegpt*
forwards_find(struct iter_forwards* fwd, uint8_t* qname, uint16_t qclass)
{
rbnode_type* res = NULL;
struct iter_forward_zone key;
key.node.key = &key;
key.dclass = qclass;
key.name = qname;
key.namelabs = dname_count_size_labels(qname, &key.namelen);
res = rbtree_search(fwd->tree, &key);
if(res) return ((struct iter_forward_zone*)res)->dp;
return NULL;
}
struct delegpt*
forwards_lookup(struct iter_forwards* fwd, uint8_t* qname, uint16_t qclass)
{
/* lookup the forward zone in the tree */
rbnode_type* res = NULL;
struct iter_forward_zone *result;
struct iter_forward_zone key;
key.node.key = &key;
key.dclass = qclass;
key.name = qname;
key.namelabs = dname_count_size_labels(qname, &key.namelen);
if(rbtree_find_less_equal(fwd->tree, &key, &res)) {
/* exact */
result = (struct iter_forward_zone*)res;
} else {
/* smaller element (or no element) */
int m;
result = (struct iter_forward_zone*)res;
if(!result || result->dclass != qclass)
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 stub */
if(result->namelabs <= m)
break;
result = result->parent;
}
}
if(result)
return result->dp;
return NULL;
}
struct delegpt*
forwards_lookup_root(struct iter_forwards* fwd, uint16_t qclass)
{
uint8_t root = 0;
return forwards_lookup(fwd, &root, qclass);
}
int
forwards_next_root(struct iter_forwards* fwd, uint16_t* dclass)
{
struct iter_forward_zone key;
rbnode_type* n;
struct iter_forward_zone* p;
if(*dclass == 0) {
/* first root item is first item in tree */
n = rbtree_first(fwd->tree);
if(n == RBTREE_NULL)
return 0;
p = (struct iter_forward_zone*)n;
if(dname_is_root(p->name)) {
*dclass = p->dclass;
return 1;
}
/* root not first item? search for higher items */
*dclass = p->dclass + 1;
return forwards_next_root(fwd, dclass);
}
/* find class n in tree, we may get a direct hit, or if we don't
* this is the last item of the previous class so rbtree_next() takes
* us to the next root (if any) */
key.node.key = &key;
key.name = (uint8_t*)"\000";
key.namelen = 1;
key.namelabs = 0;
key.dclass = *dclass;
n = NULL;
if(rbtree_find_less_equal(fwd->tree, &key, &n)) {
/* exact */
return 1;
} else {
/* smaller element */
if(!n || n == RBTREE_NULL)
return 0; /* nothing found */
n = rbtree_next(n);
if(n == RBTREE_NULL)
return 0; /* no higher */
p = (struct iter_forward_zone*)n;
if(dname_is_root(p->name)) {
*dclass = p->dclass;
return 1;
}
/* not a root node, return next higher item */
*dclass = p->dclass+1;
return forwards_next_root(fwd, dclass);
}
}
size_t
forwards_get_mem(struct iter_forwards* fwd)
{
struct iter_forward_zone* p;
size_t s;
if(!fwd)
return 0;
s = sizeof(*fwd) + sizeof(*fwd->tree);
RBTREE_FOR(p, struct iter_forward_zone*, fwd->tree) {
s += sizeof(*p) + p->namelen + delegpt_get_mem(p->dp);
}
return s;
}
static struct iter_forward_zone*
fwd_zone_find(struct iter_forwards* fwd, uint16_t c, uint8_t* nm)
{
struct iter_forward_zone key;
key.node.key = &key;
key.dclass = c;
key.name = nm;
key.namelabs = dname_count_size_labels(nm, &key.namelen);
return (struct iter_forward_zone*)rbtree_search(fwd->tree, &key);
}
int
forwards_add_zone(struct iter_forwards* fwd, uint16_t c, struct delegpt* dp)
{
struct iter_forward_zone *z;
if((z=fwd_zone_find(fwd, c, dp->name)) != NULL) {
(void)rbtree_delete(fwd->tree, &z->node);
fwd_zone_free(z);
}
if(!forwards_insert(fwd, c, dp))
return 0;
fwd_init_parents(fwd);
return 1;
}
void
forwards_delete_zone(struct iter_forwards* fwd, uint16_t c, uint8_t* nm)
{
struct iter_forward_zone *z;
if(!(z=fwd_zone_find(fwd, c, nm)))
return; /* nothing to do */
(void)rbtree_delete(fwd->tree, &z->node);
fwd_zone_free(z);
fwd_init_parents(fwd);
}
int
forwards_add_stub_hole(struct iter_forwards* fwd, uint16_t c, uint8_t* nm)
{
if(!fwd_add_stub_hole(fwd, c, nm)) {
return 0;
}
fwd_init_parents(fwd);
return 1;
}
void
forwards_delete_stub_hole(struct iter_forwards* fwd, uint16_t c, uint8_t* nm)
{
struct iter_forward_zone *z;
if(!(z=fwd_zone_find(fwd, c, nm)))
return; /* nothing to do */
if(z->dp != NULL)
return; /* not a stub hole */
(void)rbtree_delete(fwd->tree, &z->node);
fwd_zone_free(z);
fwd_init_parents(fwd);
}