aclconf.c revision e1d7ec063f854cf7db1705ff65cd0236226cf0ad
/*
* Copyright (C) 2004-2011 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 1999-2002 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
* PERFORMANCE OF THIS SOFTWARE.
*/
/* $Id: aclconf.c,v 1.32 2011/08/26 04:49:14 marka Exp $ */
#include <config.h>
#include <isc/mem.h>
#include <isc/string.h> /* Required for HP/UX (and others?) */
#include <isc/util.h>
#include <isccfg/namedconf.h>
#include <isccfg/aclconf.h>
#include <dns/acl.h>
#include <dns/iptable.h>
#include <dns/fixedname.h>
#include <dns/log.h>
#define LOOP_MAGIC ISC_MAGIC('L','O','O','P')
isc_result_t
cfg_aclconfctx_create(isc_mem_t *mctx, cfg_aclconfctx_t **ret) {
isc_result_t result;
cfg_aclconfctx_t *actx;
REQUIRE(mctx != NULL);
REQUIRE(ret != NULL && *ret == NULL);
actx = isc_mem_get(mctx, sizeof(*actx));
if (actx == NULL)
return (ISC_R_NOMEMORY);
result = isc_refcount_init(&actx->references, 1);
if (result != ISC_R_SUCCESS)
goto cleanup;
actx->mctx = NULL;
isc_mem_attach(mctx, &actx->mctx);
ISC_LIST_INIT(actx->named_acl_cache);
*ret = actx;
return (ISC_R_SUCCESS);
cleanup:
isc_mem_put(mctx, actx, sizeof(*actx));
return (result);
}
void
cfg_aclconfctx_attach(cfg_aclconfctx_t *src, cfg_aclconfctx_t **dest) {
REQUIRE(src != NULL);
REQUIRE(dest != NULL && *dest == NULL);
isc_refcount_increment(&src->references, NULL);
*dest = src;
}
void
cfg_aclconfctx_detach(cfg_aclconfctx_t **actxp) {
cfg_aclconfctx_t *actx;
dns_acl_t *dacl, *next;
unsigned int refs;
REQUIRE(actxp != NULL && *actxp != NULL);
actx = *actxp;
isc_refcount_decrement(&actx->references, &refs);
if (refs == 0) {
for (dacl = ISC_LIST_HEAD(actx->named_acl_cache);
dacl != NULL;
dacl = next)
{
next = ISC_LIST_NEXT(dacl, nextincache);
ISC_LIST_UNLINK(actx->named_acl_cache, dacl,
nextincache);
dns_acl_detach(&dacl);
}
isc_mem_putanddetach(&actx->mctx, actx, sizeof(*actx));
}
*actxp = NULL;
}
/*
* Find the definition of the named acl whose name is "name".
*/
static isc_result_t
get_acl_def(const cfg_obj_t *cctx, const char *name, const cfg_obj_t **ret) {
isc_result_t result;
const cfg_obj_t *acls = NULL;
const cfg_listelt_t *elt;
result = cfg_map_get(cctx, "acl", &acls);
if (result != ISC_R_SUCCESS)
return (result);
for (elt = cfg_list_first(acls);
elt != NULL;
elt = cfg_list_next(elt)) {
const cfg_obj_t *acl = cfg_listelt_value(elt);
const char *aclname = cfg_obj_asstring(cfg_tuple_get(acl, "name"));
if (strcasecmp(aclname, name) == 0) {
if (ret != NULL) {
*ret = cfg_tuple_get(acl, "value");
}
return (ISC_R_SUCCESS);
}
}
return (ISC_R_NOTFOUND);
}
static isc_result_t
convert_named_acl(const cfg_obj_t *nameobj, const cfg_obj_t *cctx,
isc_log_t *lctx, cfg_aclconfctx_t *ctx,
isc_mem_t *mctx, unsigned int nest_level,
dns_acl_t **target)
{
isc_result_t result;
const cfg_obj_t *cacl = NULL;
dns_acl_t *dacl;
dns_acl_t loop;
const char *aclname = cfg_obj_asstring(nameobj);
/* Look for an already-converted version. */
for (dacl = ISC_LIST_HEAD(ctx->named_acl_cache);
dacl != NULL;
dacl = ISC_LIST_NEXT(dacl, nextincache))
{
if (strcasecmp(aclname, dacl->name) == 0) {
if (ISC_MAGIC_VALID(dacl, LOOP_MAGIC)) {
cfg_obj_log(nameobj, lctx, ISC_LOG_ERROR,
"acl loop detected: %s", aclname);
return (ISC_R_FAILURE);
}
dns_acl_attach(dacl, target);
return (ISC_R_SUCCESS);
}
}
/* Not yet converted. Convert now. */
result = get_acl_def(cctx, aclname, &cacl);
if (result != ISC_R_SUCCESS) {
cfg_obj_log(nameobj, lctx, ISC_LOG_WARNING,
"undefined ACL '%s'", aclname);
return (result);
}
/*
* Add a loop detection element.
*/
memset(&loop, 0, sizeof(loop));
ISC_LINK_INIT(&loop, nextincache);
DE_CONST(aclname, loop.name);
loop.magic = LOOP_MAGIC;
ISC_LIST_APPEND(ctx->named_acl_cache, &loop, nextincache);
result = cfg_acl_fromconfig(cacl, cctx, lctx, ctx, mctx,
nest_level, &dacl);
ISC_LIST_UNLINK(ctx->named_acl_cache, &loop, nextincache);
loop.magic = 0;
loop.name = NULL;
if (result != ISC_R_SUCCESS)
return (result);
dacl->name = isc_mem_strdup(dacl->mctx, aclname);
if (dacl->name == NULL)
return (ISC_R_NOMEMORY);
ISC_LIST_APPEND(ctx->named_acl_cache, dacl, nextincache);
dns_acl_attach(dacl, target);
return (ISC_R_SUCCESS);
}
static isc_result_t
convert_keyname(const cfg_obj_t *keyobj, isc_log_t *lctx, isc_mem_t *mctx,
dns_name_t *dnsname)
{
isc_result_t result;
isc_buffer_t buf;
dns_fixedname_t fixname;
unsigned int keylen;
const char *txtname = cfg_obj_asstring(keyobj);
keylen = strlen(txtname);
isc_buffer_init(&buf, txtname, keylen);
isc_buffer_add(&buf, keylen);
dns_fixedname_init(&fixname);
result = dns_name_fromtext(dns_fixedname_name(&fixname), &buf,
dns_rootname, 0, NULL);
if (result != ISC_R_SUCCESS) {
cfg_obj_log(keyobj, lctx, ISC_LOG_WARNING,
"key name '%s' is not a valid domain name",
txtname);
return (result);
}
return (dns_name_dup(dns_fixedname_name(&fixname), mctx, dnsname));
}
/*
* Recursively pre-parse an ACL definition to find the total number
* of non-IP-prefix elements (localhost, localnets, key) in all nested
* ACLs, so that the parent will have enough space allocated for the
* elements table after all the nested ACLs have been merged in to the
* parent.
*/
static int
count_acl_elements(const cfg_obj_t *caml, const cfg_obj_t *cctx,
isc_boolean_t *has_negative)
{
const cfg_listelt_t *elt;
const cfg_obj_t *cacl = NULL;
isc_result_t result;
int n = 0;
if (has_negative != NULL)
*has_negative = ISC_FALSE;
for (elt = cfg_list_first(caml);
elt != NULL;
elt = cfg_list_next(elt)) {
const cfg_obj_t *ce = cfg_listelt_value(elt);
/* negated element; just get the value. */
if (cfg_obj_istuple(ce)) {
ce = cfg_tuple_get(ce, "value");
if (has_negative != NULL)
*has_negative = ISC_TRUE;
}
if (cfg_obj_istype(ce, &cfg_type_keyref)) {
n++;
} else if (cfg_obj_islist(ce)) {
isc_boolean_t negative;
n += count_acl_elements(ce, cctx, &negative);
if (negative)
n++;
} else if (cfg_obj_isstring(ce)) {
const char *name = cfg_obj_asstring(ce);
if (strcasecmp(name, "localhost") == 0 ||
strcasecmp(name, "localnets") == 0) {
n++;
} else if (strcasecmp(name, "any") != 0 &&
strcasecmp(name, "none") != 0) {
result = get_acl_def(cctx, name, &cacl);
if (result == ISC_R_SUCCESS)
n += count_acl_elements(cacl, cctx,
NULL) + 1;
}
}
}
return n;
}
isc_result_t
cfg_acl_fromconfig(const cfg_obj_t *caml,
const cfg_obj_t *cctx,
isc_log_t *lctx,
cfg_aclconfctx_t *ctx,
isc_mem_t *mctx,
unsigned int nest_level,
dns_acl_t **target)
{
isc_result_t result;
dns_acl_t *dacl = NULL, *inneracl = NULL;
dns_aclelement_t *de;
const cfg_listelt_t *elt;
dns_iptable_t *iptab;
int new_nest_level = 0;
if (nest_level != 0)
new_nest_level = nest_level - 1;
REQUIRE(target != NULL);
REQUIRE(*target == NULL || DNS_ACL_VALID(*target));
if (*target != NULL) {
/*
* If target already points to an ACL, then we're being
* called recursively to configure a nested ACL. The
* nested ACL's contents should just be absorbed into its
* parent ACL.
*/
dns_acl_attach(*target, &dacl);
dns_acl_detach(target);
} else {
/*
* Need to allocate a new ACL structure. Count the items
* in the ACL definition that will require space in the
* elements table. (Note that if nest_level is nonzero,
* *everything* goes in the elements table.)
*/
int nelem;
if (nest_level == 0)
nelem = count_acl_elements(caml, cctx, NULL);
else
nelem = cfg_list_length(caml, ISC_FALSE);
result = dns_acl_create(mctx, nelem, &dacl);
if (result != ISC_R_SUCCESS)
return (result);
}
de = dacl->elements;
for (elt = cfg_list_first(caml);
elt != NULL;
elt = cfg_list_next(elt)) {
const cfg_obj_t *ce = cfg_listelt_value(elt);
isc_boolean_t neg;
if (cfg_obj_istuple(ce)) {
/* This must be a negated element. */
ce = cfg_tuple_get(ce, "value");
neg = ISC_TRUE;
dacl->has_negatives = ISC_TRUE;
} else
neg = ISC_FALSE;
/*
* If nest_level is nonzero, then every element is
* to be stored as a separate, nested ACL rather than
* merged into the main iptable.
*/
iptab = dacl->iptable;
if (nest_level != 0) {
result = dns_acl_create(mctx,
cfg_list_length(ce, ISC_FALSE),
&de->nestedacl);
if (result != ISC_R_SUCCESS)
goto cleanup;
iptab = de->nestedacl->iptable;
}
if (cfg_obj_isnetprefix(ce)) {
/* Network prefix */
isc_netaddr_t addr;
unsigned int bitlen;
cfg_obj_asnetprefix(ce, &addr, &bitlen);
/*
* If nesting ACLs (nest_level != 0), we negate
* the nestedacl element, not the iptable entry.
*/
result = dns_iptable_addprefix(iptab, &addr, bitlen,
ISC_TF(nest_level != 0 || !neg));
if (result != ISC_R_SUCCESS)
goto cleanup;
if (nest_level > 0) {
de->type = dns_aclelementtype_nestedacl;
de->negative = neg;
} else
continue;
} else if (cfg_obj_islist(ce)) {
/*
* If we're nesting ACLs, put the nested
* ACL onto the elements list; otherwise
* merge it into *this* ACL. We nest ACLs
* in two cases: 1) sortlist, 2) if the
* nested ACL contains negated members.
*/
if (inneracl != NULL)
dns_acl_detach(&inneracl);
result = cfg_acl_fromconfig(ce, cctx, lctx,
ctx, mctx, new_nest_level,
&inneracl);
if (result != ISC_R_SUCCESS)
goto cleanup;
nested_acl:
if (nest_level > 0 || inneracl->has_negatives) {
de->type = dns_aclelementtype_nestedacl;
de->negative = neg;
if (de->nestedacl != NULL)
dns_acl_detach(&de->nestedacl);
dns_acl_attach(inneracl,
&de->nestedacl);
dns_acl_detach(&inneracl);
/* Fall through. */
} else {
dns_acl_merge(dacl, inneracl,
ISC_TF(!neg));
de += inneracl->length; /* elements added */
dns_acl_detach(&inneracl);
continue;
}
} else if (cfg_obj_istype(ce, &cfg_type_keyref)) {
/* Key name. */
de->type = dns_aclelementtype_keyname;
de->negative = neg;
dns_name_init(&de->keyname, NULL);
result = convert_keyname(ce, lctx, mctx,
&de->keyname);
if (result != ISC_R_SUCCESS)
goto cleanup;
} else if (cfg_obj_isstring(ce)) {
/* ACL name. */
const char *name = cfg_obj_asstring(ce);
if (strcasecmp(name, "any") == 0) {
/* Iptable entry with zero bit length. */
result = dns_iptable_addprefix(iptab, NULL, 0,
ISC_TF(nest_level != 0 || !neg));
if (result != ISC_R_SUCCESS)
goto cleanup;
if (nest_level != 0) {
de->type = dns_aclelementtype_nestedacl;
de->negative = neg;
} else
continue;
} else if (strcasecmp(name, "none") == 0) {
/* none == !any */
/*
* We don't unconditional set
* dacl->has_negatives and
* de->negative to true so we can handle
* "!none;".
*/
result = dns_iptable_addprefix(iptab, NULL, 0,
ISC_TF(nest_level != 0 || neg));
if (result != ISC_R_SUCCESS)
goto cleanup;
if (!neg)
dacl->has_negatives = !neg;
if (nest_level != 0) {
de->type = dns_aclelementtype_nestedacl;
de->negative = !neg;
} else
continue;
} else if (strcasecmp(name, "localhost") == 0) {
de->type = dns_aclelementtype_localhost;
de->negative = neg;
} else if (strcasecmp(name, "localnets") == 0) {
de->type = dns_aclelementtype_localnets;
de->negative = neg;
} else {
if (inneracl != NULL)
dns_acl_detach(&inneracl);
result = convert_named_acl(ce, cctx, lctx, ctx,
mctx, new_nest_level,
&inneracl);
if (result != ISC_R_SUCCESS)
goto cleanup;
goto nested_acl;
}
} else {
cfg_obj_log(ce, lctx, ISC_LOG_WARNING,
"address match list contains "
"unsupported element type");
result = ISC_R_FAILURE;
goto cleanup;
}
/*
* This should only be reached for localhost, localnets
* and keyname elements, and nested ACLs if nest_level is
* nonzero (i.e., in sortlists).
*/
if (de->nestedacl != NULL &&
de->type != dns_aclelementtype_nestedacl)
dns_acl_detach(&de->nestedacl);
dacl->node_count++;
de->node_num = dacl->node_count;
dacl->length++;
de++;
INSIST(dacl->length <= dacl->alloc);
}
dns_acl_attach(dacl, target);
result = ISC_R_SUCCESS;
cleanup:
if (inneracl != NULL)
dns_acl_detach(&inneracl);
dns_acl_detach(&dacl);
return (result);
}