/*
* daemon/acl_list.h - client access control storage for the server.
*
* 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 helps the server keep out queries from outside sources, that
* should not be answered.
*/
#include "config.h"
#include "daemon/acl_list.h"
#include "util/regional.h"
#include "util/log.h"
#include "util/config_file.h"
#include "util/net_help.h"
#include "services/localzone.h"
#include "sldns/str2wire.h"
struct acl_list*
acl_list_create(void)
{
struct acl_list* acl = (struct acl_list*)calloc(1,
sizeof(struct acl_list));
if(!acl)
return NULL;
acl->region = regional_create();
if(!acl->region) {
acl_list_delete(acl);
return NULL;
}
return acl;
}
void
acl_list_delete(struct acl_list* acl)
{
if(!acl)
return;
regional_destroy(acl->region);
free(acl);
}
/** insert new address into acl_list structure */
static struct acl_addr*
acl_list_insert(struct acl_list* acl, struct sockaddr_storage* addr,
socklen_t addrlen, int net, enum acl_access control,
int complain_duplicates)
{
struct acl_addr* node = regional_alloc_zero(acl->region,
sizeof(struct acl_addr));
if(!node)
return NULL;
node->control = control;
if(!addr_tree_insert(&acl->tree, &node->node, addr, addrlen, net)) {
if(complain_duplicates)
verbose(VERB_QUERY, "duplicate acl address ignored.");
}
return node;
}
/** apply acl_list string */
static int
acl_list_str_cfg(struct acl_list* acl, const char* str, const char* s2,
int complain_duplicates)
{
struct sockaddr_storage addr;
int net;
socklen_t addrlen;
enum acl_access control;
if(strcmp(s2, "allow") == 0)
control = acl_allow;
else if(strcmp(s2, "deny") == 0)
control = acl_deny;
else if(strcmp(s2, "refuse") == 0)
control = acl_refuse;
else if(strcmp(s2, "deny_non_local") == 0)
control = acl_deny_non_local;
else if(strcmp(s2, "refuse_non_local") == 0)
control = acl_refuse_non_local;
else if(strcmp(s2, "allow_snoop") == 0)
control = acl_allow_snoop;
else {
log_err("access control type %s unknown", str);
return 0;
}
if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
log_err("cannot parse access control: %s %s", str, s2);
return 0;
}
if(!acl_list_insert(acl, &addr, addrlen, net, control,
complain_duplicates)) {
log_err("out of memory");
return 0;
}
return 1;
}
/** find or create node (NULL on parse or error) */
static struct acl_addr*
acl_find_or_create(struct acl_list* acl, const char* str)
{
struct acl_addr* node;
struct sockaddr_storage addr;
int net;
socklen_t addrlen;
if(!netblockstrtoaddr(str, UNBOUND_DNS_PORT, &addr, &addrlen, &net)) {
log_err("cannot parse netblock: %s", str);
return NULL;
}
/* find or create node */
if(!(node=(struct acl_addr*)addr_tree_find(&acl->tree, &addr,
addrlen, net))) {
/* create node, type 'allow' since otherwise tags are
* pointless, can override with specific access-control: cfg */
if(!(node=(struct acl_addr*)acl_list_insert(acl, &addr,
addrlen, net, acl_allow, 1))) {
log_err("out of memory");
return NULL;
}
}
return node;
}
/** apply acl_tag string */
static int
acl_list_tags_cfg(struct acl_list* acl, const char* str, uint8_t* bitmap,
size_t bitmaplen)
{
struct acl_addr* node;
if(!(node=acl_find_or_create(acl, str)))
return 0;
node->taglen = bitmaplen;
node->taglist = regional_alloc_init(acl->region, bitmap, bitmaplen);
if(!node->taglist) {
log_err("out of memory");
return 0;
}
return 1;
}
/** apply acl_view string */
static int
acl_list_view_cfg(struct acl_list* acl, const char* str, const char* str2,
struct views* vs)
{
struct acl_addr* node;
if(!(node=acl_find_or_create(acl, str)))
return 0;
node->view = views_find_view(vs, str2, 0 /* get read lock*/);
if(!node->view) {
log_err("no view with name: %s", str2);
return 0;
}
lock_rw_unlock(&node->view->lock);
return 1;
}
/** apply acl_tag_action string */
static int
acl_list_tag_action_cfg(struct acl_list* acl, struct config_file* cfg,
const char* str, const char* tag, const char* action)
{
struct acl_addr* node;
int tagid;
enum localzone_type t;
if(!(node=acl_find_or_create(acl, str)))
return 0;
/* allocate array if not yet */
if(!node->tag_actions) {
node->tag_actions = (uint8_t*)regional_alloc_zero(acl->region,
sizeof(*node->tag_actions)*cfg->num_tags);
if(!node->tag_actions) {
log_err("out of memory");
return 0;
}
node->tag_actions_size = (size_t)cfg->num_tags;
}
/* parse tag */
if((tagid=find_tag_id(cfg, tag)) == -1) {
log_err("cannot parse tag (define-tag it): %s %s", str, tag);
return 0;
}
if((size_t)tagid >= node->tag_actions_size) {
log_err("tagid too large for array %s %s", str, tag);
return 0;
}
if(!local_zone_str2type(action, &t)) {
log_err("cannot parse access control action type: %s %s %s",
str, tag, action);
return 0;
}
node->tag_actions[tagid] = (uint8_t)t;
return 1;
}
/** check wire data parse */
static int
check_data(const char* data, const struct config_strlist* head)
{
char buf[65536];
uint8_t rr[LDNS_RR_BUF_SIZE];
size_t len = sizeof(rr);
int res;
/* '.' is sufficient for validation, and it makes the call to
* sldns_wirerr_get_type() simpler below. */
snprintf(buf, sizeof(buf), "%s %s", ".", data);
res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600, NULL, 0,
NULL, 0);
/* Reject it if we would end up having CNAME and other data (including
* another CNAME) for the same tag. */
if(res == 0 && head) {
const char* err_data = NULL;
if(sldns_wirerr_get_type(rr, len, 1) == LDNS_RR_TYPE_CNAME) {
/* adding CNAME while other data already exists. */
err_data = data;
} else {
snprintf(buf, sizeof(buf), "%s %s", ".", head->str);
len = sizeof(rr);
res = sldns_str2wire_rr_buf(buf, rr, &len, NULL, 3600,
NULL, 0, NULL, 0);
if(res != 0) {
/* This should be impossible here as head->str
* has been validated, but we check it just in
* case. */
return 0;
}
if(sldns_wirerr_get_type(rr, len, 1) ==
LDNS_RR_TYPE_CNAME) /* already have CNAME */
err_data = head->str;
}
if(err_data) {
log_err("redirect tag data '%s' must not coexist with "
"other data.", err_data);
return 0;
}
}
if(res == 0)
return 1;
log_err("rr data [char %d] parse error %s",
(int)LDNS_WIREPARSE_OFFSET(res)-13,
sldns_get_errorstr_parse(res));
return 0;
}
/** apply acl_tag_data string */
static int
acl_list_tag_data_cfg(struct acl_list* acl, struct config_file* cfg,
const char* str, const char* tag, const char* data)
{
struct acl_addr* node;
int tagid;
char* dupdata;
if(!(node=acl_find_or_create(acl, str)))
return 0;
/* allocate array if not yet */
if(!node->tag_datas) {
node->tag_datas = (struct config_strlist**)regional_alloc_zero(
acl->region, sizeof(*node->tag_datas)*cfg->num_tags);
if(!node->tag_datas) {
log_err("out of memory");
return 0;
}
node->tag_datas_size = (size_t)cfg->num_tags;
}
/* parse tag */
if((tagid=find_tag_id(cfg, tag)) == -1) {
log_err("cannot parse tag (define-tag it): %s %s", str, tag);
return 0;
}
if((size_t)tagid >= node->tag_datas_size) {
log_err("tagid too large for array %s %s", str, tag);
return 0;
}
/* check data? */
if(!check_data(data, node->tag_datas[tagid])) {
log_err("cannot parse access-control-tag data: %s %s '%s'",
str, tag, data);
return 0;
}
dupdata = regional_strdup(acl->region, data);
if(!dupdata) {
log_err("out of memory");
return 0;
}
if(!cfg_region_strlist_insert(acl->region,
&(node->tag_datas[tagid]), dupdata)) {
log_err("out of memory");
return 0;
}
return 1;
}
/** read acl_list config */
static int
read_acl_list(struct acl_list* acl, struct config_file* cfg)
{
struct config_str2list* p;
for(p = cfg->acls; p; p = p->next) {
log_assert(p->str && p->str2);
if(!acl_list_str_cfg(acl, p->str, p->str2, 1))
return 0;
}
return 1;
}
/** read acl tags config */
static int
read_acl_tags(struct acl_list* acl, struct config_file* cfg)
{
struct config_strbytelist* np, *p = cfg->acl_tags;
cfg->acl_tags = NULL;
while(p) {
log_assert(p->str && p->str2);
if(!acl_list_tags_cfg(acl, p->str, p->str2, p->str2len)) {
config_del_strbytelist(p);
return 0;
}
/* free the items as we go to free up memory */
np = p->next;
free(p->str);
free(p->str2);
free(p);
p = np;
}
return 1;
}
/** read acl view config */
static int
read_acl_view(struct acl_list* acl, struct config_file* cfg, struct views* v)
{
struct config_str2list* np, *p = cfg->acl_view;
cfg->acl_view = NULL;
while(p) {
log_assert(p->str && p->str2);
if(!acl_list_view_cfg(acl, p->str, p->str2, v)) {
return 0;
}
/* free the items as we go to free up memory */
np = p->next;
free(p->str);
free(p->str2);
free(p);
p = np;
}
return 1;
}
/** read acl tag actions config */
static int
read_acl_tag_actions(struct acl_list* acl, struct config_file* cfg)
{
struct config_str3list* p, *np;
p = cfg->acl_tag_actions;
cfg->acl_tag_actions = NULL;
while(p) {
log_assert(p->str && p->str2 && p->str3);
if(!acl_list_tag_action_cfg(acl, cfg, p->str, p->str2,
p->str3)) {
config_deltrplstrlist(p);
return 0;
}
/* free the items as we go to free up memory */
np = p->next;
free(p->str);
free(p->str2);
free(p->str3);
free(p);
p = np;
}
return 1;
}
/** read acl tag datas config */
static int
read_acl_tag_datas(struct acl_list* acl, struct config_file* cfg)
{
struct config_str3list* p, *np;
p = cfg->acl_tag_datas;
cfg->acl_tag_datas = NULL;
while(p) {
log_assert(p->str && p->str2 && p->str3);
if(!acl_list_tag_data_cfg(acl, cfg, p->str, p->str2, p->str3)) {
config_deltrplstrlist(p);
return 0;
}
/* free the items as we go to free up memory */
np = p->next;
free(p->str);
free(p->str2);
free(p->str3);
free(p);
p = np;
}
return 1;
}
int
acl_list_apply_cfg(struct acl_list* acl, struct config_file* cfg,
struct views* v)
{
regional_free_all(acl->region);
addr_tree_init(&acl->tree);
if(!read_acl_list(acl, cfg))
return 0;
if(!read_acl_view(acl, cfg, v))
return 0;
if(!read_acl_tags(acl, cfg))
return 0;
if(!read_acl_tag_actions(acl, cfg))
return 0;
if(!read_acl_tag_datas(acl, cfg))
return 0;
/* insert defaults, with '0' to ignore them if they are duplicates */
if(!acl_list_str_cfg(acl, "0.0.0.0/0", "refuse", 0))
return 0;
if(!acl_list_str_cfg(acl, "127.0.0.0/8", "allow", 0))
return 0;
if(cfg->do_ip6) {
if(!acl_list_str_cfg(acl, "::0/0", "refuse", 0))
return 0;
if(!acl_list_str_cfg(acl, "::1", "allow", 0))
return 0;
if(!acl_list_str_cfg(acl, "::ffff:127.0.0.1", "allow", 0))
return 0;
}
addr_tree_init_parents(&acl->tree);
return 1;
}
enum acl_access
acl_get_control(struct acl_addr* acl)
{
if(acl) return acl->control;
return acl_deny;
}
struct acl_addr*
acl_addr_lookup(struct acl_list* acl, struct sockaddr_storage* addr,
socklen_t addrlen)
{
return (struct acl_addr*)addr_tree_lookup(&acl->tree,
addr, addrlen);
}
size_t
acl_list_get_mem(struct acl_list* acl)
{
if(!acl) return 0;
return sizeof(*acl) + regional_get_mem(acl->region);
}
