/*
* 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"
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 int
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(acl->region,
sizeof(struct acl_addr));
if(!node)
return 0;
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 1;
}
/** 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;
}
/** 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;
}
int
acl_list_apply_cfg(struct acl_list* acl, struct config_file* cfg)
{
regional_free_all(acl->region);
addr_tree_init(&acl->tree);
if(!read_acl_list(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_list_lookup(struct acl_list* acl, struct sockaddr_storage* addr,
socklen_t addrlen)
{
struct acl_addr* r = (struct acl_addr*)addr_tree_lookup(&acl->tree,
addr, addrlen);
if(r) return r->control;
return acl_deny;
}
size_t
acl_list_get_mem(struct acl_list* acl)
{
if(!acl) return 0;
return sizeof(*acl) + regional_get_mem(acl->region);
}
