update.c revision 40f53fa8d9c6a4fc38c0014495e7a42b08f52481
/*
* Copyright (C) 1999, 2000 Internet Software Consortium.
*
* Permission to use, copy, modify, and 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 INTERNET SOFTWARE CONSORTIUM
* DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
* INTERNET SOFTWARE CONSORTIUM 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: update.c,v 1.60 2000/08/01 01:12:00 tale Exp $ */
#include <config.h>
#include <isc/string.h>
#include <isc/taskpool.h>
#include <isc/util.h>
#include <dns/db.h>
#include <dns/dbiterator.h>
#include <dns/dnssec.h>
#include <dns/events.h>
#include <dns/fixedname.h>
#include <dns/journal.h>
#include <dns/message.h>
#include <dns/nxt.h>
#include <dns/rdataset.h>
#include <dns/rdatasetiter.h>
#include <dns/ssu.h>
#include <dns/view.h>
#include <dns/zone.h>
#include <dns/zt.h>
#include <named/client.h>
#include <named/log.h>
#include <named/update.h>
/*
* This module implements dynamic update as in RFC2136.
*/
/*
XXX TODO:
- forwarding
- document strict minimality
*/
/**************************************************************************/
/*
* Convenience macro of common isc_log_write() arguments
* to use in reportings server errors.
*/
#define UPDATE_ERROR_LOGARGS \
ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE, \
ISC_LOG_ERROR
/*
* Convenience macro of common isc_log_write() arguments
* to use in tracing dynamic update protocol requests.
*/
#define UPDATE_PROTOCOL_LOGARGS \
ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE, \
ISC_LOG_INFO
/*
* Convenience macro of common isc_log_write() arguments
* to use in low-level debug tracing.
*/
#define UPDATE_DEBUG_LOGARGS \
ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE, \
ISC_LOG_DEBUG(8)
/*
* Check an operation for failure. These macros all assume that
* the function using them has a 'result' variable and a 'failure'
* label.
*/
#define CHECK(op) \
do { result = (op); \
if (result != ISC_R_SUCCESS) goto failure; \
} while (0)
/*
* Fail unconditionally with result 'code', which must not
* be ISC_R_SUCCESS. The reason for failure presumably has
* been logged already.
*
* The test against ISC_R_SUCCESS is there to keep the Solaris compiler
* from complaining about "end-of-loop code not reached".
*/
#define FAIL(code) \
do { \
result = (code); \
if (result != ISC_R_SUCCESS) goto failure; \
} while (0)
/*
* Fail unconditionally and log as a client error.
* The test against ISC_R_SUCCESS is there to keep the Solaris compiler
* from complaining about "end-of-loop code not reached".
*/
#define FAILC(code, msg) \
do { \
result = (code); \
isc_log_write(UPDATE_PROTOCOL_LOGARGS, \
"dynamic update failed: %s (%s)", \
msg, isc_result_totext(result)); \
if (result != ISC_R_SUCCESS) goto failure; \
} while (0)
/*
* Fail unconditionally and log as a server error.
* The test against ISC_R_SUCCESS is there to keep the Solaris compiler
* from complaining about "end-of-loop code not reached".
*/
#define FAILS(code, msg) \
do { \
result = (code); \
isc_log_write(UPDATE_PROTOCOL_LOGARGS, \
"dynamic update error: %s: %s", \
msg, isc_result_totext(result)); \
if (result != ISC_R_SUCCESS) goto failure; \
} while (0)
/**************************************************************************/
typedef struct rr rr_t;
struct rr {
/* dns_name_t name; */
isc_uint32_t ttl;
dns_rdata_t rdata;
};
typedef struct update_event update_event_t;
struct update_event {
ISC_EVENT_COMMON(update_event_t);
dns_zone_t *zone;
isc_result_t result;
};
/**************************************************************************/
/*
* Forward declarations.
*/
static void update_action(isc_task_t *task, isc_event_t *event);
static void updatedone_action(isc_task_t *task, isc_event_t *event);
/**************************************************************************/
/*
* Update a single RR in version 'ver' of 'db' and log the
* update in 'diff'.
*
* Ensures:
* '*tuple' == NULL. Either the tuple is freed, or its
* ownership has been transferred to the diff.
*/
static isc_result_t
do_one_tuple(dns_difftuple_t **tuple,
dns_db_t *db, dns_dbversion_t *ver,
dns_diff_t *diff)
{
dns_diff_t temp_diff;
isc_result_t result;
/*
* Create a singleton diff.
*/
dns_diff_init(diff->mctx, &temp_diff);
ISC_LIST_APPEND(temp_diff.tuples, *tuple, link);
/*
* Apply it to the database.
*/
result = dns_diff_apply(&temp_diff, db, ver);
if (result != ISC_R_SUCCESS) {
dns_difftuple_free(tuple);
return (result);
}
/*
* Merge it into the current pending journal entry.
*/
dns_diff_appendminimal(diff, tuple);
/*
* Do not clear temp_diff.
*/
return (ISC_R_SUCCESS);
}
static isc_result_t
update_one_rr(dns_db_t *db, dns_dbversion_t *ver, dns_diff_t *diff,
dns_diffop_t op, dns_name_t *name,
dns_ttl_t ttl, dns_rdata_t *rdata)
{
dns_difftuple_t *tuple = NULL;
isc_result_t result;
result = dns_difftuple_create(diff->mctx, op,
name, ttl, rdata, &tuple);
if (result != ISC_R_SUCCESS)
return (result);
return (do_one_tuple(&tuple, db, ver, diff));
}
/**************************************************************************/
/*
* Callback-style iteration over rdatasets and rdatas.
*
* foreach_rrset() can be used to iterate over the RRsets
* of a name and call a callback function with each
* one. Similarly, foreach_rr() can be used to iterate
* over the individual RRs at name, optionally restricted
* to RRs of a given type.
*
* The callback functions are called "actions" and take
* two arguments: a void pointer for passing arbitrary
* context information, and a pointer to the current RRset
* or RR. By convention, their names end in "_action".
*/
/*
* XXXRTH We might want to make this public somewhere in libdns.
*/
/*
* Function type for foreach_rrset() iterator actions.
*/
typedef isc_result_t rrset_func(void *data, dns_rdataset_t *rrset);
/*
* Function type for foreach_rr() iterator actions.
*/
typedef isc_result_t rr_func(void *data, rr_t *rr);
/*
* Internal context struct for foreach_node_rr().
*/
typedef struct {
rr_func * rr_action;
void * rr_action_data;
} foreach_node_rr_ctx_t;
/*
* Internal helper function for foreach_node_rr().
*/
static isc_result_t
foreach_node_rr_action(void *data, dns_rdataset_t *rdataset) {
isc_result_t result;
foreach_node_rr_ctx_t *ctx = data;
for (result = dns_rdataset_first(rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(rdataset))
{
rr_t rr;
dns_rdataset_current(rdataset, &rr.rdata);
rr.ttl = rdataset->ttl;
result = (*ctx->rr_action)(ctx->rr_action_data, &rr);
if (result != ISC_R_SUCCESS)
return (result);
}
if (result != ISC_R_NOMORE)
return (result);
return (ISC_R_SUCCESS);
}
/*
* For each rdataset of 'name' in 'ver' of 'db', call 'action'
* with the rdataset and 'action_data' as arguments. If the name
* does not exist, do nothing.
*
* If 'action' returns an error, abort iteration and return the error.
*/
static isc_result_t
foreach_rrset(dns_db_t *db,
dns_dbversion_t *ver,
dns_name_t *name,
rrset_func *action,
void *action_data)
{
isc_result_t result;
dns_dbnode_t *node;
dns_rdatasetiter_t *iter;
node = NULL;
result = dns_db_findnode(db, name, ISC_FALSE, &node);
if (result == ISC_R_NOTFOUND)
return (ISC_R_SUCCESS);
if (result != ISC_R_SUCCESS)
return (result);
iter = NULL;
result = dns_db_allrdatasets(db, node, ver,
(isc_stdtime_t) 0, &iter);
if (result != ISC_R_SUCCESS)
goto cleanup_node;
for (result = dns_rdatasetiter_first(iter);
result == ISC_R_SUCCESS;
result = dns_rdatasetiter_next(iter))
{
dns_rdataset_t rdataset;
dns_rdataset_init(&rdataset);
dns_rdatasetiter_current(iter, &rdataset);
result = (*action)(action_data, &rdataset);
dns_rdataset_disassociate(&rdataset);
if (result != ISC_R_SUCCESS)
goto cleanup_iterator;
}
if (result == ISC_R_NOMORE)
result = ISC_R_SUCCESS;
cleanup_iterator:
dns_rdatasetiter_destroy(&iter);
cleanup_node:
dns_db_detachnode(db, &node);
return (result);
}
/*
* For each RR of 'name' in 'ver' of 'db', call 'action'
* with the RR and 'action_data' as arguments. If the name
* does not exist, do nothing.
*
* If 'action' returns an error, abort iteration
* and return the error.
*/
static isc_result_t
foreach_node_rr(dns_db_t *db,
dns_dbversion_t *ver,
dns_name_t *name,
rr_func *rr_action,
void *rr_action_data)
{
foreach_node_rr_ctx_t ctx;
ctx.rr_action = rr_action;
ctx.rr_action_data = rr_action_data;
return (foreach_rrset(db, ver, name,
foreach_node_rr_action, &ctx));
}
/*
* For each of the RRs specified by 'db', 'ver', 'name', 'type',
* (which can be dns_rdatatype_any to match any type), and 'covers', call
* 'action' with the RR and 'action_data' as arguments. If the name
* does not exist, or if no RRset of the given type exists at the name,
* do nothing.
*
* If 'action' returns an error, abort iteration and return the error.
*/
static isc_result_t
foreach_rr(dns_db_t *db,
dns_dbversion_t *ver,
dns_name_t *name,
dns_rdatatype_t type,
dns_rdatatype_t covers,
rr_func *rr_action,
void *rr_action_data)
{
isc_result_t result;
dns_dbnode_t *node;
dns_rdataset_t rdataset;
if (type == dns_rdatatype_any)
return (foreach_node_rr(db, ver, name,
rr_action, rr_action_data));
node = NULL;
result = dns_db_findnode(db, name, ISC_FALSE, &node);
if (result == ISC_R_NOTFOUND)
return (ISC_R_SUCCESS);
if (result != ISC_R_SUCCESS)
return (result);
dns_rdataset_init(&rdataset);
result = dns_db_findrdataset(db, node, ver, type, covers,
(isc_stdtime_t) 0, &rdataset, NULL);
if (result == ISC_R_NOTFOUND) {
result = ISC_R_SUCCESS;
goto cleanup_node;
}
if (result != ISC_R_SUCCESS)
goto cleanup_node;
for (result = dns_rdataset_first(&rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&rdataset))
{
rr_t rr;
dns_rdataset_current(&rdataset, &rr.rdata);
rr.ttl = rdataset.ttl;
result = (*rr_action)(rr_action_data, &rr);
if (result != ISC_R_SUCCESS)
goto cleanup_rdataset;
}
if (result != ISC_R_NOMORE)
goto cleanup_rdataset;
result = ISC_R_SUCCESS;
cleanup_rdataset:
dns_rdataset_disassociate(&rdataset);
cleanup_node:
dns_db_detachnode(db, &node);
return (result);
}
/**************************************************************************/
/*
* Various tests on the database contents (for prerequisites, etc).
*/
/*
* Function type for predicate functions that compare a database RR 'db_rr'
* against an update RR 'update_rr'.
*/
typedef isc_boolean_t rr_predicate(dns_rdata_t *update_rr, dns_rdata_t *db_rr);
/*
* Helper function for rrset_exists().
*/
static isc_result_t
rrset_exists_action(void *data, rr_t *rr) {
UNUSED(data);
UNUSED(rr);
return (ISC_R_EXISTS);
}
/*
* Utility macro for RR existence checking functions.
*
* If the variable 'result' has the value ISC_R_EXISTS or
* ISC_R_SUCCESS, set *exists to ISC_TRUE or ISC_FALSE,
* respectively, and return success.
*
* If 'result' has any other value, there was a failure.
* Return the failure result code and do not set *exists.
*
* This would be more readable as "do { if ... } while(0)",
* but that form generates tons of warnings on Solaris 2.6.
*/
#define RETURN_EXISTENCE_FLAG \
return ((result == ISC_R_EXISTS) ? \
(*exists = ISC_TRUE, ISC_R_SUCCESS) : \
((result == ISC_R_SUCCESS) ? \
(*exists = ISC_FALSE, ISC_R_SUCCESS) : \
result));
/*
* Set '*exists' to true iff an rrset of the given type exists,
* to false otherwise.
*/
static isc_result_t
rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
dns_name_t *name, dns_rdatatype_t type, dns_rdatatype_t covers,
isc_boolean_t *exists)
{
isc_result_t result;
result = foreach_rr(db, ver, name, type, covers,
rrset_exists_action, NULL);
RETURN_EXISTENCE_FLAG;
}
/*
* Helper function for cname_incompatible_rrset_exists.
*/
static isc_result_t
cname_compatibility_action(void *data, dns_rdataset_t *rrset) {
UNUSED(data);
if (rrset->type != dns_rdatatype_cname &&
! dns_rdatatype_isdnssec(rrset->type))
return (ISC_R_EXISTS);
return (ISC_R_SUCCESS);
}
/*
* Check whether there is an rrset incompatible with adding a CNAME RR,
* i.e., anything but another CNAME (which can be replaced) or a
* DNSSEC RR (which can coexist).
*
* If such an incompatible rrset exists, set '*exists' to ISC_TRUE.
* Otherwise, set it to ISC_FALSE.
*/
static isc_result_t
cname_incompatible_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
dns_name_t *name, isc_boolean_t *exists) {
isc_result_t result;
result = foreach_rrset(db, ver, name,
cname_compatibility_action, NULL);
RETURN_EXISTENCE_FLAG;
}
/*
* Helper function for rr_count().
*/
static isc_result_t
count_rr_action(void *data, rr_t *rr) {
int *countp = data;
UNUSED(rr);
(*countp)++;
return (ISC_R_SUCCESS);
}
/*
* Count the number of RRs of 'type' belonging to 'name' in 'ver' of 'db'.
*/
static isc_result_t
rr_count(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
dns_rdatatype_t type, dns_rdatatype_t covers, int *countp)
{
*countp = 0;
return (foreach_rr(db, ver, name, type, covers,
count_rr_action, countp));
}
/*
* Context struct for matching_rr_exists().
*/
typedef struct {
rr_predicate *predicate;
dns_db_t *db;
dns_dbversion_t *ver;
dns_name_t *name;
dns_rdata_t *update_rr;
} matching_rr_exists_ctx_t;
/*
* Helper function for matching_rr_exists().
*/
static isc_result_t
matching_rr_exists_action(void *data, rr_t *rr) {
matching_rr_exists_ctx_t *ctx = data;
if ((*ctx->predicate)(ctx->update_rr, &rr->rdata))
return (ISC_R_EXISTS);
return (ISC_R_SUCCESS);
}
/*
* Compare the 'update_rr' with all RRs in the RRset specified by 'db',
* 'ver', 'name', and 'type' using 'predicate'. If the predicate returns
* true for at least one of them, set '*exists' to ISC_TRUE. Otherwise,
* set it to ISC_FALSE.
*/
static isc_result_t
matching_rr_exists(rr_predicate *predicate,
dns_db_t *db,
dns_dbversion_t *ver,
dns_name_t *name,
dns_rdatatype_t type,
dns_rdatatype_t covers,
dns_rdata_t *update_rr,
isc_boolean_t *exists)
{
isc_result_t result;
matching_rr_exists_ctx_t ctx;
ctx.predicate = predicate;
ctx.db = db;
ctx.ver = ver;
ctx.name = name;
ctx.update_rr = update_rr;
result = foreach_rr(db, ver, name, type, covers,
matching_rr_exists_action, &ctx);
RETURN_EXISTENCE_FLAG;
}
/*
* Context struct and helper function for name_exists().
*/
static isc_result_t
name_exists_action(void *data, dns_rdataset_t *rrset) {
UNUSED(data);
UNUSED(rrset);
return (ISC_R_EXISTS);
}
/*
* Set '*exists' to true iff the given name exists, to false otherwise.
*/
static isc_result_t
name_exists(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
isc_boolean_t *exists)
{
isc_result_t result;
result = foreach_rrset(db, ver, name,
name_exists_action, NULL);
RETURN_EXISTENCE_FLAG;
}
typedef struct {
dns_name_t *name, *signer;
dns_ssutable_t *table;
} ssu_check_t;
static isc_result_t
ssu_checkrule(void *data, dns_rdataset_t *rrset) {
ssu_check_t *ssuinfo = data;
isc_boolean_t result;
/*
* If we're deleting all records, it's ok to delete SIG and NXT even
* if we're normally not allowed to.
*/
if (rrset->type == dns_rdatatype_sig ||
rrset->type == dns_rdatatype_nxt)
return (ISC_TRUE);
result = dns_ssutable_checkrules(ssuinfo->table, ssuinfo->signer,
ssuinfo->name, rrset->type);
return (result == ISC_TRUE ? ISC_R_SUCCESS : ISC_R_FAILURE);
}
static isc_boolean_t
ssu_checkall(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
dns_ssutable_t *ssutable, dns_name_t *signer)
{
isc_result_t result;
ssu_check_t ssuinfo;
ssuinfo.name = name;
ssuinfo.table = ssutable;
ssuinfo.signer = signer;
result = foreach_rrset(db, ver, name, ssu_checkrule, &ssuinfo);
return (ISC_TF(result == ISC_R_SUCCESS));
}
/**************************************************************************/
/*
* Checking of "RRset exists (value dependent)" prerequisites.
*
* In the RFC2136 section 3.2.5, this is the pseudocode involving
* a variable called "temp", a mapping of <name, type> tuples to rrsets.
*
* Here, we represent the "temp" data structure as (non-minimial) "dns_diff_t"
* where each typle has op==DNS_DIFFOP_EXISTS.
*/
/*
* Append a tuple asserting the existence of the RR with
* 'name' and 'rdata' to 'diff'.
*/
static isc_result_t
temp_append(dns_diff_t *diff, dns_name_t *name, dns_rdata_t *rdata) {
isc_result_t result;
dns_difftuple_t *tuple = NULL;
REQUIRE(DNS_DIFF_VALID(diff));
CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_EXISTS,
name, 0, rdata, &tuple));
ISC_LIST_APPEND(diff->tuples, tuple, link);
failure:
return (result);
}
/*
* Compare two rdatasets represented as sorted lists of tuples.
* All list elements must have the same owner name and type.
* Return ISC_R_SUCCESS if the rdatasets are equal, rcode(dns_rcode_nxrrset)
* if not.
*/
static isc_result_t
temp_check_rrset(dns_difftuple_t *a, dns_difftuple_t *b) {
for (;;) {
if (a == NULL || b == NULL)
break;
INSIST(a->op == DNS_DIFFOP_EXISTS &&
b->op == DNS_DIFFOP_EXISTS);
INSIST(a->rdata.type == b->rdata.type);
INSIST(dns_name_equal(&a->name, &b->name));
if (dns_rdata_compare(&a->rdata, &b->rdata) != 0)
return (DNS_R_NXRRSET);
a = ISC_LIST_NEXT(a, link);
b = ISC_LIST_NEXT(b, link);
}
if (a != NULL || b != NULL)
return (DNS_R_NXRRSET);
return (ISC_R_SUCCESS);
}
/*
* A comparison function defining the sorting order for the entries
* in the "temp" data structure. The major sort key is the owner name,
* followed by the type and rdata.
*/
static int
temp_order(const void *av, const void *bv) {
dns_difftuple_t * const *ap = av;
dns_difftuple_t * const *bp = bv;
dns_difftuple_t *a = *ap;
dns_difftuple_t *b = *bp;
int r;
r = dns_name_compare(&a->name, &b->name);
if (r != 0)
return (r);
r = (b->rdata.type - a->rdata.type);
if (r != 0)
return (r);
r = dns_rdata_compare(&a->rdata, &b->rdata);
return (r);
}
/*
* Check the "RRset exists (value dependent)" prerequisite information
* in 'temp' against the contents of the database 'db'.
*
* Return ISC_R_SUCCESS if the prerequisites are satisfied,
* rcode(dns_rcode_nxrrset) if not.
*/
static isc_result_t
temp_check(isc_mem_t *mctx, dns_diff_t *temp, dns_db_t *db,
dns_dbversion_t *ver)
{
isc_result_t result;
dns_name_t *name;
dns_dbnode_t *node;
dns_difftuple_t *t;
dns_diff_t trash;
/* Exit early if the list is empty (for efficiency only). */
if (ISC_LIST_HEAD(temp->tuples) == NULL)
return (ISC_R_SUCCESS);
/*
* Sort the prerequisite records by owner name,
* type, and rdata.
*/
result = dns_diff_sort(temp, temp_order);
if (result != ISC_R_SUCCESS)
return (result);
dns_diff_init(mctx, &trash);
/*
* For each name and type in the prerequisites,
* construct a sorted rdata list of the corresponding
* database contents, and compare the lists.
*/
t = ISC_LIST_HEAD(temp->tuples);
while (t != NULL) {
name = &t->name;
/* A new unique name begins here. */
node = NULL;
result = dns_db_findnode(db, name, ISC_FALSE, &node);
if (result == ISC_R_NOTFOUND)
return (DNS_R_NXRRSET);
if (result != ISC_R_SUCCESS)
return (result);
/* A new unique type begins here. */
while (t != NULL && dns_name_equal(&t->name, name)) {
dns_rdatatype_t type, covers;
dns_rdataset_t rdataset;
dns_diff_t d_rrs; /* Database RRs with
this name and type */
dns_diff_t u_rrs; /* Update RRs with
this name and type */
type = t->rdata.type;
if (type == dns_rdatatype_sig)
covers = dns_rdata_covers(&t->rdata);
else
covers = 0;
/*
* Collect all database RRs for this name and type
* onto d_rrs and sort them.
*/
dns_rdataset_init(&rdataset);
result = dns_db_findrdataset(db, node, ver, type,
covers, (isc_stdtime_t) 0,
&rdataset, NULL);
if (result != ISC_R_SUCCESS) {
dns_db_detachnode(db, &node);
return (DNS_R_NXRRSET);
}
dns_diff_init(mctx, &d_rrs);
dns_diff_init(mctx, &u_rrs);
for (result = dns_rdataset_first(&rdataset);
result == ISC_R_SUCCESS;
result = dns_rdataset_next(&rdataset))
{
dns_rdata_t rdata;
dns_rdataset_current(&rdataset, &rdata);
result = temp_append(&d_rrs, name, &rdata);
if (result != ISC_R_SUCCESS)
goto failure;
}
if (result != ISC_R_NOMORE)
goto failure;
result = dns_diff_sort(&d_rrs, temp_order);
if (result != ISC_R_SUCCESS)
goto failure;
/*
* Collect all update RRs for this name and type
* onto u_rrs. No need to sort them here -
* they are already sorted.
*/
while (t != NULL &&
dns_name_equal(&t->name, name) &&
t->rdata.type == type)
{
dns_difftuple_t *next =
ISC_LIST_NEXT(t, link);
ISC_LIST_UNLINK(temp->tuples, t, link);
ISC_LIST_APPEND(u_rrs.tuples, t, link);
t = next;
}
/* Compare the two sorted lists. */
result = temp_check_rrset(ISC_LIST_HEAD(u_rrs.tuples),
ISC_LIST_HEAD(d_rrs.tuples));
if (result != ISC_R_SUCCESS)
goto failure;
/*
* We are done with the tuples, but we can't free
* them yet because "name" still points into one
* of them. Move them on a temporary list.
*/
ISC_LIST_APPENDLIST(trash.tuples, u_rrs.tuples, link);
ISC_LIST_APPENDLIST(trash.tuples, d_rrs.tuples, link);
dns_rdataset_disassociate(&rdataset);
continue;
failure:
dns_diff_clear(&d_rrs);
dns_diff_clear(&u_rrs);
dns_diff_clear(&trash);
dns_rdataset_disassociate(&rdataset);
dns_db_detachnode(db, &node);
return (result);
}
dns_db_detachnode(db, &node);
}
dns_diff_clear(&trash);
return (ISC_R_SUCCESS);
}
/**************************************************************************/
/*
* Conditional deletion of RRs.
*/
/*
* Context structure for delete_if().
*/
typedef struct {
rr_predicate *predicate;
dns_db_t *db;
dns_dbversion_t *ver;
dns_diff_t *diff;
dns_name_t *name;
dns_rdata_t *update_rr;
} conditional_delete_ctx_t;
/*
* Predicate functions for delete_if().
*/
/*
* Return true iff 'update_rr' is neither a SOA nor an NS RR.
*/
static isc_boolean_t
type_not_soa_nor_ns_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
UNUSED(update_rr);
return ((db_rr->type != dns_rdatatype_soa &&
db_rr->type != dns_rdatatype_ns) ?
ISC_TRUE : ISC_FALSE);
}
/*
* Return true always.
*/
static isc_boolean_t
true_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
UNUSED(update_rr);
UNUSED(db_rr);
return (ISC_TRUE);
}
/*
* Return true iff the two RRs have identical rdata.
*/
static isc_boolean_t
rr_equal_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
/*
* XXXRTH This is not a problem, but we should consider creating
* dns_rdata_equal() (that used dns_name_equal()), since it
* would be faster. Not a priority.
*/
return (dns_rdata_compare(update_rr, db_rr) == 0 ?
ISC_TRUE : ISC_FALSE);
}
/*
* Return true iff 'update_rr' should replace 'db_rr' according
* to the special RFC2136 rules for CNAME, SOA, and WKS records.
*/
static isc_boolean_t
replaces_p(dns_rdata_t *update_rr, dns_rdata_t *db_rr) {
if (db_rr->type != update_rr->type)
return (ISC_FALSE);
if (db_rr->type == dns_rdatatype_cname)
return (ISC_TRUE);
if (db_rr->type == dns_rdatatype_soa)
return (ISC_TRUE);
/*
* RFC2136 does not mention NXT, but multiple NXTs make little
* sense, so we replace those, too.
*/
if (db_rr->type == dns_rdatatype_nxt)
return (ISC_TRUE);
if (db_rr->type == dns_rdatatype_wks) {
/*
* Compare the address and protocol fields only. These
* form the first five bytes of the RR data. Do a
* raw binary comparison; unpacking the WKS RRs using
* dns_rdata_tostruct() might be cleaner in some ways,
* but it would require us to pass around an mctx.
*/
INSIST(db_rr->length >= 5 && update_rr->length >= 5);
return (memcmp(db_rr->data, update_rr->data, 5) == 0 ?
ISC_TRUE : ISC_FALSE);
}
return (ISC_FALSE);
}
/*
* Internal helper function for delete_if().
*/
static isc_result_t
delete_if_action(void *data, rr_t *rr) {
conditional_delete_ctx_t *ctx = data;
if ((*ctx->predicate)(ctx->update_rr, &rr->rdata)) {
isc_result_t result;
result = update_one_rr(ctx->db, ctx->ver, ctx->diff,
DNS_DIFFOP_DEL, ctx->name,
rr->ttl, &rr->rdata);
return (result);
} else {
return (ISC_R_SUCCESS);
}
}
/*
* Conditionally delete RRs. Apply 'predicate' to the RRs
* specified by 'db', 'ver', 'name', and 'type' (which can
* be dns_rdatatype_any to match any type). Delete those
* RRs for which the predicate returns true, and log the
* deletions in 'diff'.
*/
static isc_result_t
delete_if(rr_predicate *predicate,
dns_db_t *db,
dns_dbversion_t *ver,
dns_name_t *name,
dns_rdatatype_t type,
dns_rdatatype_t covers,
dns_rdata_t *update_rr,
dns_diff_t *diff)
{
conditional_delete_ctx_t ctx;
ctx.predicate = predicate;
ctx.db = db;
ctx.ver = ver;
ctx.diff = diff;
ctx.name = name;
ctx.update_rr = update_rr;
return (foreach_rr(db, ver, name, type, covers,
delete_if_action, &ctx));
}
/**************************************************************************/
/*
* Miscellaneous subroutines.
*/
/*
* Extract a single update RR from 'section' of dynamic update message
* 'msg', with consistency checking.
*
* Stores the owner name, rdata, and TTL of the update RR at 'name',
* 'rdata', and 'ttl', respectively.
*/
static void
get_current_rr(dns_message_t *msg, dns_section_t section,
dns_rdataclass_t zoneclass,
dns_name_t **name, dns_rdata_t *rdata, dns_rdatatype_t *covers,
dns_ttl_t *ttl,
dns_rdataclass_t *update_class)
{
dns_rdataset_t *rdataset;
isc_result_t result;
dns_message_currentname(msg, section, name);
rdataset = ISC_LIST_HEAD((*name)->list);
INSIST(rdataset != NULL);
INSIST(ISC_LIST_NEXT(rdataset, link) == NULL);
*covers = rdataset->covers;
*ttl = rdataset->ttl;
result = dns_rdataset_first(rdataset);
INSIST(result == ISC_R_SUCCESS);
dns_rdataset_current(rdataset, rdata);
INSIST(dns_rdataset_next(rdataset) == ISC_R_NOMORE);
*update_class = rdata->rdclass;
rdata->rdclass = zoneclass;
}
/*
* Increment the SOA serial number of database 'db', version 'ver'.
* Replace the SOA record in the database, and log the
* change in 'diff'.
*/
/*
* XXXRTH Failures in this routine will be worth logging, when
* we have a logging system. Failure to find the zonename
* or the SOA rdataset warrant at least an UNEXPECTED_ERROR().
*/
static isc_result_t
increment_soa_serial(dns_db_t *db, dns_dbversion_t *ver,
dns_diff_t *diff, isc_mem_t *mctx)
{
dns_difftuple_t *deltuple = NULL;
dns_difftuple_t *addtuple = NULL;
isc_uint32_t serial;
isc_result_t result;
CHECK(dns_db_createsoatuple(db, ver, mctx, DNS_DIFFOP_DEL, &deltuple));
CHECK(dns_difftuple_copy(deltuple, &addtuple));
addtuple->op = DNS_DIFFOP_ADD;
serial = dns_soa_getserial(&addtuple->rdata);
/* RFC1982 */
serial = (serial + 1) & 0xFFFFFFFF;
if (serial == 0)
serial = 1;
dns_soa_setserial(serial, &addtuple->rdata);
CHECK(do_one_tuple(&addtuple, db, ver, diff));
CHECK(do_one_tuple(&deltuple, db, ver, diff));
result = ISC_R_SUCCESS;
failure:
if (addtuple != NULL)
dns_difftuple_free(&addtuple);
if (deltuple != NULL)
dns_difftuple_free(&deltuple);
return (result);
}
/*
* Check that the new SOA record at 'update_rdata' does not
* illegally cause the SOA serial number to decrease or stay
* unchanged relative to the existing SOA in 'db'.
*
* Sets '*ok' to ISC_TRUE if the update is legal, ISC_FALSE if not.
*
* William King points out that RFC2136 is inconsistent about
* the case where the serial number stays unchanged:
*
* section 3.4.2.2 requires a server to ignore a SOA update request
* if the serial number on the update SOA is less_than_or_equal to
* the zone SOA serial.
*
* section 3.6 requires a server to ignore a SOA update request if
* the serial is less_than the zone SOA serial.
*
* Paul says 3.4.2.2 is correct.
*
*/
static isc_result_t
check_soa_increment(dns_db_t *db, dns_dbversion_t *ver,
dns_rdata_t *update_rdata,
isc_boolean_t *ok)
{
isc_uint32_t db_serial;
isc_uint32_t update_serial;
isc_result_t result;
update_serial = dns_soa_getserial(update_rdata);
result = dns_db_getsoaserial(db, ver, &db_serial);
if (result != ISC_R_SUCCESS)
return (result);
if (DNS_SERIAL_GE(db_serial, update_serial)) {
*ok = ISC_FALSE;
} else {
*ok = ISC_TRUE;
}
return (ISC_R_SUCCESS);
}
/**************************************************************************/
/*
* Incremental updating of NXTs and SIGs.
*/
#define MAXZONEKEYS 32 /* Maximum number of zone keys supported. */
/*
* We abuse the dns_diff_t type to represent a set of domain names
* affected by the update.
*/
static isc_result_t
namelist_append_name(dns_diff_t *list, dns_name_t *name) {
isc_result_t result;
dns_difftuple_t *tuple = NULL;
static dns_rdata_t dummy_rdata = { NULL, 0, 0, 0, { NULL, NULL } };
CHECK(dns_difftuple_create(list->mctx, DNS_DIFFOP_EXISTS, name, 0,
&dummy_rdata, &tuple));
dns_diff_append(list, &tuple);
failure:
return (result);
}
static isc_result_t
namelist_append_subdomain(dns_db_t *db, dns_name_t *name, dns_diff_t *affected)
{
isc_result_t result;
dns_fixedname_t fixedname;
dns_name_t *child;
dns_dbiterator_t *dbit = NULL;
dns_fixedname_init(&fixedname);
child = dns_fixedname_name(&fixedname);
CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
for (result = dns_dbiterator_seek(dbit, name);
result == ISC_R_SUCCESS;
result = dns_dbiterator_next(dbit))
{
dns_dbnode_t *node = NULL;
result = dns_dbiterator_current(dbit, &node, child);
dns_db_detachnode(db, &node);
CHECK(result);
if (! dns_name_issubdomain(child, name))
break;
CHECK(namelist_append_name(affected, child));
}
failure:
if (dbit != NULL)
dns_dbiterator_destroy(&dbit);
return (result);
}
/*
* Helper function for non_nxt_rrset_exists().
*/
static isc_result_t
is_non_nxt_action(void *data, dns_rdataset_t *rrset) {
UNUSED(data);
if (!(rrset->type == dns_rdatatype_nxt ||
(rrset->type == dns_rdatatype_sig &&
rrset->covers == dns_rdatatype_nxt)))
return (ISC_R_EXISTS);
return (ISC_R_SUCCESS);
}
/*
* Check whether there is an rrset other than a NXT or SIG NXT,
* i.e., anything that justifies the continued existence of a name
* after a secure update.
*
* If such an rrset exists, set '*exists' to ISC_TRUE.
* Otherwise, set it to ISC_FALSE.
*/
static isc_result_t
non_nxt_rrset_exists(dns_db_t *db, dns_dbversion_t *ver,
dns_name_t *name, isc_boolean_t *exists)
{
isc_result_t result;
result = foreach_rrset(db, ver, name,
is_non_nxt_action, NULL);
RETURN_EXISTENCE_FLAG;
}
/*
* A comparison function for sorting dns_diff_t:s by name.
*/
static int
name_order(const void *av, const void *bv) {
dns_difftuple_t * const *ap = av;
dns_difftuple_t * const *bp = bv;
dns_difftuple_t *a = *ap;
dns_difftuple_t *b = *bp;
return (dns_name_compare(&a->name, &b->name));
}
static isc_result_t
uniqify_name_list(dns_diff_t *list) {
isc_result_t result;
dns_difftuple_t *p, *q;
CHECK(dns_diff_sort(list, name_order));
p = ISC_LIST_HEAD(list->tuples);
while (p != NULL) {
do {
q = ISC_LIST_NEXT(p, link);
if (q == NULL || ! dns_name_equal(&p->name, &q->name))
break;
ISC_LIST_UNLINK(list->tuples, q, link);
dns_difftuple_free(&q);
} while (1);
p = ISC_LIST_NEXT(p, link);
}
failure:
return (result);
}
static isc_result_t
is_glue(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
isc_boolean_t *flag)
{
isc_result_t result;
dns_fixedname_t foundname;
dns_fixedname_init(&foundname);
result = dns_db_find(db, name, ver, dns_rdatatype_any,
DNS_DBFIND_GLUEOK | DNS_DBFIND_NOWILD,
(isc_stdtime_t) 0, NULL,
dns_fixedname_name(&foundname),
NULL, NULL);
if (result == ISC_R_SUCCESS) {
*flag = ISC_FALSE;
return (ISC_R_SUCCESS);
} else if (result == DNS_R_ZONECUT) {
/* XXX should omit non-delegation types from NXT */
*flag = ISC_FALSE;
return (ISC_R_SUCCESS);
} else if (result == DNS_R_GLUE) {
*flag = ISC_TRUE;
return (ISC_R_SUCCESS);
} else {
return (result);
}
}
/*
* Find the next/previous name that has a NXT record.
* In other words, skip empty database nodes and names that
* have had their NXTs removed because they are obscured by
* a zone cut.
*/
static isc_result_t
next_active(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *oldname,
dns_name_t *newname, isc_boolean_t forward)
{
isc_result_t result;
dns_dbiterator_t *dbit = NULL;
isc_boolean_t has_nxt;
CHECK(dns_db_createiterator(db, ISC_FALSE, &dbit));
CHECK(dns_dbiterator_seek(dbit, oldname));
do {
dns_dbnode_t *node = NULL;
if (forward)
result = dns_dbiterator_next(dbit);
else
result = dns_dbiterator_prev(dbit);
if (result == ISC_R_NOMORE) {
/*
* Wrap around.
*/
if (forward)
CHECK(dns_dbiterator_first(dbit));
else
CHECK(dns_dbiterator_last(dbit));
}
dns_dbiterator_current(dbit, &node, newname);
dns_db_detachnode(db, &node);
/*
* The iterator may hold the tree lock, and
* rrset_exists() calls dns_db_findnode() which
* may try to reacquire it. To avoid deadlock
* we must pause the iterator first.
*/
CHECK(dns_dbiterator_pause(dbit));
CHECK(rrset_exists(db, ver, newname,
dns_rdatatype_nxt, 0, &has_nxt));
} while (! has_nxt);
failure:
if (dbit != NULL)
dns_dbiterator_destroy(&dbit);
return (result);
}
/*
* Add a NXT record for "name", recording the change in "diff".
*/
static isc_result_t
add_nxt(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name, dns_diff_t *diff)
{
isc_result_t result;
dns_dbnode_t *node = NULL;
unsigned char buffer[DNS_NXT_BUFFERSIZE];
dns_rdata_t rdata;
dns_difftuple_t *tuple = NULL;
dns_fixedname_t fixedname;
dns_name_t *target;
dns_fixedname_init(&fixedname);
target = dns_fixedname_name(&fixedname);
/*
* Find the successor name, aka NXT target.
*/
CHECK(next_active(db, ver, name, target, ISC_TRUE));
/*
* Create the NXT RDATA.
*/
CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
dns_rdata_init(&rdata);
CHECK(dns_buildnxtrdata(db, ver, node, target, buffer, &rdata));
dns_db_detachnode(db, &node);
/*
* Create a diff tuple, update the database, and record the change.
*/
CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name,
3600, /* XXXRTH */
&rdata, &tuple));
CHECK(do_one_tuple(&tuple, db, ver, diff));
INSIST(tuple == NULL);
failure:
if (node != NULL)
dns_db_detachnode(db, &node);
return (result);
}
/*
* Add a placeholder NXT record for "name", recording the change in "diff".
*/
static isc_result_t
add_placeholder_nxt(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
dns_diff_t *diff) {
isc_result_t result;
dns_difftuple_t *tuple = NULL;
isc_region_t r;
unsigned char data[1] = { 0 }; /* The root domain, no bits. */
dns_rdata_t rdata;
r.base = data;
r.length = sizeof data;
dns_rdata_fromregion(&rdata, dns_db_class(db), dns_rdatatype_nxt, &r);
CHECK(dns_difftuple_create(diff->mctx, DNS_DIFFOP_ADD, name, 0,
&rdata, &tuple));
CHECK(do_one_tuple(&tuple, db, ver, diff));
failure:
return (result);
}
static isc_result_t
find_zone_keys(dns_db_t *db, dns_dbversion_t *ver, isc_mem_t *mctx,
unsigned int maxkeys, dst_key_t **keys, unsigned int *nkeys)
{
isc_result_t result;
dns_dbnode_t *node = NULL;
CHECK(dns_db_findnode(db, dns_db_origin(db), ISC_FALSE, &node));
CHECK(dns_dnssec_findzonekeys(db, ver, node, dns_db_origin(db),
mctx, maxkeys, keys, nkeys));
failure:
if (node != NULL)
dns_db_detachnode(db, &node);
return (result);
}
/*
* Add SIG records for an RRset, recording the change in "diff".
*/
static isc_result_t
add_sigs(dns_db_t *db, dns_dbversion_t *ver, dns_name_t *name,
dns_rdatatype_t type, dns_diff_t *diff, dst_key_t **keys,
unsigned int nkeys, isc_mem_t *mctx, isc_stdtime_t inception,
isc_stdtime_t expire)
{
isc_result_t result;
dns_dbnode_t *node = NULL;
dns_rdataset_t rdataset;
dns_rdata_t sig_rdata;
isc_buffer_t buffer;
unsigned char data[1024]; /* XXX */
unsigned int i;
dns_rdataset_init(&rdataset);
isc_buffer_init(&buffer, data, sizeof(data));
/* Get the rdataset to sign. */
CHECK(dns_db_findnode(db, name, ISC_FALSE, &node));
CHECK(dns_db_findrdataset(db, node, ver, type, 0,
(isc_stdtime_t) 0,
&rdataset, NULL));
dns_db_detachnode(db, &node);
for (i = 0; i < nkeys; i++) {
/* Calculate the signature, creating a SIG RDATA. */
CHECK(dns_dnssec_sign(name, &rdataset, keys[i],
&inception, &expire,
mctx, &buffer, &sig_rdata));
/* Update the database and journal with the SIG. */
/* XXX inefficient - will cause dataset merging */
CHECK(update_one_rr(db, ver, diff, DNS_DIFFOP_ADD, name,
rdataset.ttl, &sig_rdata));
}
failure:
if (dns_rdataset_isassociated(&rdataset))
dns_rdataset_disassociate(&rdataset);
if (node != NULL)
dns_db_detachnode(db, &node);
return (result);
}
/*
* Update SIG and NXT records affected by an update. The original
* update, including the SOA serial update but exluding the SIG & NXT
* changes, is in "diff" and has already been applied to "newver" of "db".
* The database version prior to the update is "oldver".
*
* The necessary SIG and NXT changes will be applied to "newver"
* and added (as a minimal diff) to "diff".
*
* The SIGs generated will be valid for 'sigvalidityinterval' seconds.
*/
static isc_result_t
update_signatures(isc_mem_t *mctx, dns_db_t *db, dns_dbversion_t *oldver,
dns_dbversion_t *newver, dns_diff_t *diff,
isc_uint32_t sigvalidityinterval)
{
isc_result_t result;
dns_difftuple_t *t;
dns_diff_t diffnames;
dns_diff_t affected;
dns_diff_t sig_diff;
dns_diff_t nxt_diff;
dns_diff_t nxt_mindiff;
isc_boolean_t flag;
dst_key_t *zone_keys[MAXZONEKEYS];
unsigned int nkeys = 0;
unsigned int i;
isc_stdtime_t now, inception, expire;
dns_diff_init(mctx, &diffnames);
dns_diff_init(mctx, &affected);
dns_diff_init(mctx, &sig_diff);
dns_diff_init(mctx, &nxt_diff);
dns_diff_init(mctx, &nxt_mindiff);
result = find_zone_keys(db, newver, mctx,
MAXZONEKEYS, zone_keys, &nkeys);
if (result != ISC_R_SUCCESS) {
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE,
NS_LOGMODULE_UPDATE, ISC_LOG_ERROR,
"could not get zone keys for secure "
"dynamic update");
goto failure;
}
isc_stdtime_get(&now);
inception = now - 3600; /* Allow for some clock skew. */
expire = now + sigvalidityinterval;
/*
* Find all RRsets directly affected by the update, and
* update their SIGs. Also build a list of names affected
* by the update in "diffnames".
*/
CHECK(dns_diff_sort(diff, temp_order));
t = ISC_LIST_HEAD(diff->tuples);
while (t != NULL) {
dns_name_t *name = &t->name;
/* Now "name" is a new, unique name affected by the update. */
CHECK(namelist_append_name(&diffnames, name));
while (t != NULL && dns_name_equal(&t->name, name)) {
dns_rdatatype_t type;
type = t->rdata.type;
/*
* Now "name" and "type" denote a new unique RRset
* affected by the update.
*/
/* Don't sign SIGs. */
if (type == dns_rdatatype_sig)
goto skip;
/*
* Delete all old SIGs covering this type, since they
* are all invalid when the signed RRset has changed.
* We may not be able to recreate all of them - tough.
*/
CHECK(delete_if(true_p, db, newver, name,
dns_rdatatype_sig, type,
NULL, &sig_diff));
/*
* If this RRset still exists after the update,
* add a new signature for it.
*/
CHECK(rrset_exists(db, newver, name, type, 0, &flag));
if (flag) {
CHECK(add_sigs(db, newver, name, type,
&sig_diff, zone_keys, nkeys,
mctx, inception, expire));
}
skip:
/* Skip any other updates to the same RRset. */
while (t != NULL &&
dns_name_equal(&t->name, name) &&
t->rdata.type == type)
{
t = ISC_LIST_NEXT(t, link);
}
}
}
/* Remove orphaned NXTs and SIG NXTs. */
for (t = ISC_LIST_HEAD(diffnames.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
CHECK(non_nxt_rrset_exists(db, newver, &t->name, &flag));
if (! flag) {
CHECK(delete_if(true_p, db, newver, &t->name,
dns_rdatatype_any, 0,
NULL, &sig_diff));
}
}
/*
* When a name is created or deleted, its predecessor needs to
* have its NXT updated.
*/
for (t = ISC_LIST_HEAD(diffnames.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
isc_boolean_t existed, exists;
dns_fixedname_t fixedname;
dns_name_t *prevname;
dns_fixedname_init(&fixedname);
prevname = dns_fixedname_name(&fixedname);
CHECK(name_exists(db, oldver, &t->name, &existed));
CHECK(name_exists(db, newver, &t->name, &exists));
if (exists == existed)
continue;
/*
* Find the predecessor.
* When names become obscured or unobscured in this update
* transaction, we may find the wrong predecessor because
* the NXTs have not yet been updated to reflect the delegation
* change. This should not matter because in this case,
* the correct predecessor is either the delegation node or
* a newly unobscured node, and those nodes are on the
* "affected" list in any case.
*/
CHECK(next_active(db, newver, &t->name, prevname, ISC_FALSE));
CHECK(namelist_append_name(&affected, prevname));
}
/* Find names affected by delegation changes. */
for (t = ISC_LIST_HEAD(diffnames.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
isc_boolean_t existed, exists;
CHECK(rrset_exists(db, oldver, &t->name, dns_rdatatype_ns, 0,
&existed));
CHECK(rrset_exists(db, newver, &t->name, dns_rdatatype_ns, 0,
&exists));
if (exists == existed)
continue;
/*
* There was a delegation change. Mark all subdomains
* of t->name as potentially needing a NXT update.
*/
CHECK(namelist_append_subdomain(db, &t->name, &affected));
}
ISC_LIST_APPENDLIST(affected.tuples, diffnames.tuples, link);
INSIST(ISC_LIST_EMPTY(diffnames.tuples));
CHECK(uniqify_name_list(&affected));
/*
* Determine which names should have NXTs, and delete/create
* NXTs to make it so. We don't know the final NXT targets yet,
* so we just create placeholder NXTs with arbitrary contents
* to indicate that their respective owner names should be part of
* the NXT chain.
*/
for (t = ISC_LIST_HEAD(affected.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
isc_boolean_t exists;
CHECK(name_exists(db, newver, &t->name, &exists));
if (! exists)
continue;
CHECK(is_glue(db, newver, &t->name, &flag));
if (flag) {
/*
* This name is obscured. Delete any
* existing NXT record.
*/
CHECK(delete_if(true_p, db, newver, &t->name,
dns_rdatatype_nxt, 0,
NULL, &nxt_diff));
} else {
/*
* This name is not obscured. It should have a NXT.
*/
CHECK(rrset_exists(db, newver, &t->name,
dns_rdatatype_nxt, 0, &flag));
if (! flag) {
add_placeholder_nxt(db, newver, &t->name,
diff);
}
}
}
/*
* Now we know which names are part of the NXT chain.
* Make them all point at their correct targets.
*/
for (t = ISC_LIST_HEAD(affected.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
CHECK(rrset_exists(db, newver, &t->name,
dns_rdatatype_nxt, 0, &flag));
if (flag) {
/*
* There is a NXT, but we don't know if it is correct.
* Delete it and create a correct one to be sure.
* If the update was unnecessary, the diff minimization
* will take care of eliminating it from the journal,
* IXFRs, etc.
*
* The SIG bit should always be set in the NXTs
* we generate, because they will all get SIG NXTs.
* (XXX what if the zone keys are missing?).
* Because the SIG NXTs have not necessarily been
* created yet, the correctness of the bit mask relies
* on the assumption that NXTs are only created if
* there is other data, and if there is other data,
* there are other SIGs.
*/
CHECK(delete_if(true_p, db, newver, &t->name,
dns_rdatatype_nxt, 0,
NULL, &nxt_diff));
CHECK(add_nxt(db, newver, &t->name, &nxt_diff));
}
}
/*
* Minimize the set of NXT updates so that we don't
* have to regenerate the SIG NXTs for NXTs that were
* replaced with identical ones.
*/
while ((t = ISC_LIST_HEAD(nxt_diff.tuples)) != NULL) {
ISC_LIST_UNLINK(nxt_diff.tuples, t, link);
dns_diff_appendminimal(&nxt_mindiff, &t);
}
/* Update SIG NXTs. */
for (t = ISC_LIST_HEAD(nxt_mindiff.tuples);
t != NULL;
t = ISC_LIST_NEXT(t, link))
{
if (t->op == DNS_DIFFOP_DEL) {
CHECK(delete_if(true_p, db, newver, &t->name,
dns_rdatatype_sig, dns_rdatatype_nxt,
NULL, &sig_diff));
} else if (t->op == DNS_DIFFOP_ADD) {
CHECK(add_sigs(db, newver, &t->name, dns_rdatatype_nxt,
&sig_diff, zone_keys, nkeys, mctx,
inception, expire));
} else {
INSIST(0);
}
}
/* Record our changes for the journal. */
while ((t = ISC_LIST_HEAD(sig_diff.tuples)) != NULL) {
ISC_LIST_UNLINK(sig_diff.tuples, t, link);
dns_diff_appendminimal(diff, &t);
}
while ((t = ISC_LIST_HEAD(nxt_mindiff.tuples)) != NULL) {
ISC_LIST_UNLINK(nxt_mindiff.tuples, t, link);
dns_diff_appendminimal(diff, &t);
}
INSIST(ISC_LIST_EMPTY(sig_diff.tuples));
INSIST(ISC_LIST_EMPTY(nxt_diff.tuples));
INSIST(ISC_LIST_EMPTY(nxt_mindiff.tuples));
failure:
dns_diff_clear(&sig_diff);
dns_diff_clear(&nxt_diff);
dns_diff_clear(&nxt_mindiff);
dns_diff_clear(&affected);
dns_diff_clear(&diffnames);
for (i = 0; i < nkeys; i++)
dst_key_free(&zone_keys[i]);
return (result);
}
/**************************************************************************/
/*
* The actual update code in all its glory. We try to follow
* the RFC2136 pseudocode as closely as possible.
*/
static isc_result_t
send_update_event(ns_client_t *client, dns_zone_t *zone) {
isc_result_t result = ISC_R_SUCCESS;
update_event_t *event = NULL;
isc_task_t *zonetask = NULL;
ns_client_t *evclient;
event = (update_event_t *)
isc_event_allocate(client->mctx, client, DNS_EVENT_UPDATE,
update_action, NULL, sizeof(*event));
if (event == NULL)
FAIL(ISC_R_NOMEMORY);
event->zone = zone;
event->result = ISC_R_SUCCESS;
evclient = NULL;
ns_client_attach(client, &evclient);
event->ev_arg = evclient;
dns_zone_gettask(zone, &zonetask);
isc_task_send(zonetask, (isc_event_t **)&event);
failure:
if (event != NULL)
isc_event_free((isc_event_t **)&event);
return (result);
}
static void
respond(ns_client_t *client, isc_result_t result) {
isc_result_t msg_result;
msg_result = dns_message_reply(client->message, ISC_TRUE);
if (msg_result != ISC_R_SUCCESS)
goto msg_failure;
client->message->rcode = dns_result_torcode(result);
ns_client_send(client);
return;
msg_failure:
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE, NS_LOGMODULE_UPDATE,
ISC_LOG_ERROR,
"could not create update response message: %s",
isc_result_totext(msg_result));
ns_client_next(client, msg_result);
}
void
ns_update_start(ns_client_t *client) {
dns_message_t *request = client->message;
isc_result_t result;
dns_name_t *zonename;
dns_rdataset_t *zone_rdataset;
dns_zone_t *zone = NULL;
/*
* Interpret the zone section.
*/
result = dns_message_firstname(request, DNS_SECTION_ZONE);
if (result != ISC_R_SUCCESS)
FAILC(DNS_R_FORMERR,
"update zone section empty");
/*
* The zone section must contain exactly one "question", and
* it must be of type SOA.
*/
zonename = NULL;
dns_message_currentname(request, DNS_SECTION_ZONE, &zonename);
zone_rdataset = ISC_LIST_HEAD(zonename->list);
if (zone_rdataset->type != dns_rdatatype_soa)
FAILC(DNS_R_FORMERR,
"update zone section contains non-SOA");
if (ISC_LIST_NEXT(zone_rdataset, link) != NULL)
FAILC(DNS_R_FORMERR,
"update zone section contains multiple RRs");
/* The zone section must have exactly one name. */
result = dns_message_nextname(request, DNS_SECTION_ZONE);
if (result != ISC_R_NOMORE)
FAILC(DNS_R_FORMERR,
"update zone section contains multiple RRs");
result = dns_zt_find(client->view->zonetable, zonename, 0, NULL,
&zone);
if (result != ISC_R_SUCCESS)
FAILC(DNS_R_NOTAUTH,
"not authoritative for update zone");
switch(dns_zone_gettype(zone)) {
case dns_zone_master:
CHECK(send_update_event(client, zone));
break; /* OK. */
case dns_zone_slave:
FAILS(DNS_R_NOTIMP,
"update forwarding"); /* XXX implement */
default:
FAILC(DNS_R_NOTAUTH,
"not authoritative for update zone");
}
return;
failure:
/*
* We failed without having sent an update event to the zone.
* We are still in the client task context, so we can
* simply give an error response without switching tasks.
*/
respond(client, result);
}
static void
update_action(isc_task_t *task, isc_event_t *event) {
update_event_t *uev = (update_event_t *) event;
dns_zone_t *zone = uev->zone;
ns_client_t *client = (ns_client_t *)event->ev_arg;
isc_result_t result;
dns_db_t *db = NULL;
dns_dbversion_t *oldver = NULL;
dns_dbversion_t *ver = NULL;
dns_diff_t diff; /* Pending updates. */
dns_diff_t temp; /* Pending RR existence assertions. */
isc_boolean_t soa_serial_changed = ISC_FALSE;
isc_mem_t *mctx = client->mctx;
dns_rdatatype_t covers;
dns_message_t *request = client->message;
dns_rdataclass_t zoneclass;
dns_name_t *zonename;
dns_ssutable_t *ssutable = NULL;
INSIST(event->ev_type == DNS_EVENT_UPDATE);
dns_diff_init(mctx, &diff);
dns_diff_init(mctx, &temp);
CHECK(dns_zone_getdb(zone, &db));
zonename = dns_db_origin(db);
zoneclass = dns_db_class(db);
dns_zone_getssutable(zone, &ssutable);
dns_db_currentversion(db, &oldver);
CHECK(dns_db_newversion(db, &ver));
/*
* Check prerequisites.
*/
for (result = dns_message_firstname(request, DNS_SECTION_PREREQUISITE);
result == ISC_R_SUCCESS;
result = dns_message_nextname(request, DNS_SECTION_PREREQUISITE))
{
dns_name_t *name = NULL;
dns_rdata_t rdata;
dns_ttl_t ttl;
dns_rdataclass_t update_class;
isc_boolean_t flag;
get_current_rr(request, DNS_SECTION_PREREQUISITE, zoneclass,
&name, &rdata, &covers, &ttl, &update_class);
if (ttl != 0)
FAILC(DNS_R_FORMERR, "prerequisite TTL is not zero");
if (! dns_name_issubdomain(name, zonename))
FAILC(DNS_R_NOTZONE,
"prerequisite name is out of zone");
if (update_class == dns_rdataclass_any) {
if (rdata.length != 0)
FAILC(DNS_R_FORMERR,
"class ANY prerequisite "
"RDATA is not empty");
if (rdata.type == dns_rdatatype_any) {
CHECK(name_exists(db, ver, name, &flag));
if (! flag) {
FAILC(DNS_R_NXDOMAIN,
"'name in use' prerequisite "
"not satisfied");
}
} else {
CHECK(rrset_exists(db, ver, name,
rdata.type, covers, &flag));
if (! flag) {
/* RRset does not exist. */
FAILC(DNS_R_NXRRSET,
"'rrset exists (value independent)' "
"prerequisite not satisfied");
}
}
} else if (update_class == dns_rdataclass_none) {
if (rdata.length != 0)
FAILC(DNS_R_FORMERR,
"class NONE prerequisite"
"RDATA is not empty");
if (rdata.type == dns_rdatatype_any) {
CHECK(name_exists(db, ver, name, &flag));
if (flag) {
FAILC(DNS_R_YXDOMAIN,
"'name not in use' prerequisite "
"not satisfied");
}
} else {
CHECK(rrset_exists(db, ver, name,
rdata.type, covers, &flag));
if (flag) {
/* RRset exists. */
FAILC(DNS_R_YXRRSET,
"'rrset does not exist' "
"prerequisite not satisfied");
}
}
} else if (update_class == zoneclass) {
/* "temp<rr.name, rr.type> += rr;" */
result = temp_append(&temp, name, &rdata);
if (result != ISC_R_SUCCESS) {
UNEXPECTED_ERROR(__FILE__, __LINE__,
"temp entry creation failed: %s",
dns_result_totext(result));
FAIL(ISC_R_UNEXPECTED);
}
} else {
FAILC(DNS_R_FORMERR, "malformed prerequisite");
}
}
if (result != ISC_R_NOMORE)
FAIL(result);
/*
* Perform the final check of the "rrset exists (value dependent)"
* prerequisites.
*/
result = temp_check(mctx, &temp, db, ver);
if (result != ISC_R_SUCCESS)
FAILC(result, "'RRset exists (value dependent)' "
"prerequisite not satisfied");
isc_log_write(UPDATE_DEBUG_LOGARGS, "prerequisites are OK");
/*
* Check Requestor's Permissions. It seems a bit silly to do this
* only after prerequisite testing, but that is what RFC2136 says.
*/
if (ssutable == NULL)
CHECK(ns_client_checkacl(client, "update",
dns_zone_getupdateacl(zone),
ISC_FALSE, ISC_TRUE));
else if (client->signer == NULL) {
/* This gets us a free log message. */
CHECK(ns_client_checkacl(client, "update", NULL, ISC_FALSE,
ISC_TRUE));
}
/*
* Perform the Update Section Prescan.
*/
for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
result == ISC_R_SUCCESS;
result = dns_message_nextname(request, DNS_SECTION_UPDATE))
{
dns_name_t *name = NULL;
dns_rdata_t rdata;
dns_ttl_t ttl;
dns_rdataclass_t update_class;
get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
&name, &rdata, &covers, &ttl, &update_class);
if (! dns_name_issubdomain(name, zonename))
FAILC(DNS_R_NOTZONE,
"update RR is outside zone");
if (update_class == zoneclass) {
/*
* Check for meta-RRs. The RFC2136 pseudocode says
* check for ANY|AXFR|MAILA|MAILB, but the text adds
* "or any other QUERY metatype"
*/
if (dns_rdatatype_ismeta(rdata.type)) {
FAILC(DNS_R_FORMERR,
"meta-RR in update");
}
} else if (update_class == dns_rdataclass_any) {
if (ttl != 0 || rdata.length != 0 ||
(dns_rdatatype_ismeta(rdata.type) &&
rdata.type != dns_rdatatype_any))
FAILC(DNS_R_FORMERR,
"meta-RR in update");
} else if (update_class == dns_rdataclass_none) {
if (ttl != 0 ||
dns_rdatatype_ismeta(rdata.type))
FAILC(DNS_R_FORMERR,
"meta-RR in update");
} else {
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE,
NS_LOGMODULE_UPDATE, ISC_LOG_WARNING,
"update RR has incorrect class %d",
update_class);
FAIL(DNS_R_FORMERR);
}
/*
* draft-ietf-dnsind-simple-secure-update-01 says
* "Unlike traditional dynamic update, the client
* is forbidden from updating NXT records."
*/
if (dns_db_issecure(db)) {
if (rdata.type == dns_rdatatype_nxt) {
FAILC(DNS_R_REFUSED,
"explicit NXT updates are not allowed "
"in secure zones");
}
else if (rdata.type == dns_rdatatype_sig) {
FAILC(DNS_R_REFUSED,
"explicit SIG updates are currently not "
"supported in secure zones");
}
}
if (ssutable != NULL && client->signer != NULL) {
if (rdata.type != dns_rdatatype_any) {
if (!dns_ssutable_checkrules(ssutable,
client->signer,
name, rdata.type))
FAILC(DNS_R_REFUSED,
"rejected by secure update");
}
else {
if (!ssu_checkall(db, ver, name, ssutable,
client->signer))
FAILC(DNS_R_REFUSED,
"rejected by secure update");
}
}
}
if (result != ISC_R_NOMORE)
FAIL(result);
isc_log_write(UPDATE_DEBUG_LOGARGS, "update section prescan OK");
/*
* Process the Update Section.
*/
for (result = dns_message_firstname(request, DNS_SECTION_UPDATE);
result == ISC_R_SUCCESS;
result = dns_message_nextname(request, DNS_SECTION_UPDATE))
{
dns_name_t *name = NULL;
dns_rdata_t rdata;
dns_ttl_t ttl;
dns_rdataclass_t update_class;
isc_boolean_t flag;
get_current_rr(request, DNS_SECTION_UPDATE, zoneclass,
&name, &rdata, &covers, &ttl, &update_class);
if (update_class == zoneclass) {
if (rdata.type == dns_rdatatype_cname) {
CHECK(cname_incompatible_rrset_exists(db, ver,
name,
&flag));
if (flag) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to add CNAME "
"alongside non-CNAME "
"ignored");
continue;
}
} else {
CHECK(rrset_exists(db, ver, name,
dns_rdatatype_cname, 0,
&flag));
if (flag &&
! dns_rdatatype_isdnssec(rdata.type))
{
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to add non-CNAME "
"alongside CNAME ignored");
continue;
}
}
if (rdata.type == dns_rdatatype_soa) {
isc_boolean_t ok;
CHECK(rrset_exists(db, ver, name,
dns_rdatatype_soa, 0,
&flag));
if (! flag) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to create 2nd "
"SOA ignored");
continue;
}
CHECK(check_soa_increment(db, ver, &rdata,
&ok));
if (! ok) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"SOA update failed to "
"increment serial, "
"ignoring it");
continue;
}
soa_serial_changed = ISC_TRUE;
}
/*
* Add an RR. If an identical RR already exists,
* do nothing. If a similar but not identical
* CNAME, SOA, or WKS exists, remove it first.
*/
CHECK(matching_rr_exists(rr_equal_p, db, ver, name,
rdata.type, covers, &rdata,
&flag));
if (! flag) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"adding an RR");
CHECK(delete_if(replaces_p, db, ver, name,
rdata.type, covers, &rdata,
&diff));
result = update_one_rr(db, ver, &diff,
DNS_DIFFOP_ADD,
name, ttl, &rdata);
if (result != ISC_R_SUCCESS)
FAIL(result);
} else {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to add existing RR "
"ignored");
}
} else if (update_class == dns_rdataclass_any) {
if (rdata.type == dns_rdatatype_any) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"delete all rrsets from a name");
if (dns_name_equal(name, zonename)) {
CHECK(delete_if(type_not_soa_nor_ns_p,
db, ver, name,
dns_rdatatype_any, 0,
&rdata, &diff));
} else {
CHECK(delete_if(true_p, db, ver, name,
dns_rdatatype_any, 0,
&rdata, &diff));
}
} else if (dns_name_equal(name, zonename) &&
(rdata.type == dns_rdatatype_soa ||
rdata.type == dns_rdatatype_ns)) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to delete all SOA "
"or NS records ignored");
continue;
} else {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"deleting an rrset");
CHECK(delete_if(true_p, db, ver, name,
rdata.type, covers, &rdata,
&diff));
}
} else if (update_class == dns_rdataclass_none) {
/*
* The (name == zonename) condition appears in
* RFC2136 3.4.2.4 but is missing from the pseudocode.
*/
if (dns_name_equal(name, zonename)) {
if (rdata.type == dns_rdatatype_soa) {
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"attempt to delete SOA "
"ignored");
continue;
}
if (rdata.type == dns_rdatatype_ns) {
int count;
CHECK(rr_count(db, ver, name,
dns_rdatatype_ns,
0, &count));
if (count == 1) {
isc_log_write(
UPDATE_PROTOCOL_LOGARGS,
"attempt to delete last "
"NS ignored");
continue;
}
}
}
isc_log_write(UPDATE_PROTOCOL_LOGARGS,
"deleting an RR");
CHECK(delete_if(rr_equal_p, db, ver, name,
rdata.type, covers, &rdata, &diff));
}
}
if (result != ISC_R_NOMORE)
FAIL(result);
/*
* If any changes were made, increment the SOA serial number,
* update SIGs and NXTs (if zone is secure), and write the update
* to the journal.
*/
if (! ISC_LIST_EMPTY(diff.tuples)) {
dns_journal_t *journal;
/*
* Increment the SOA serial, but only if it was not
* changed as a result of an update operation.
*/
if (! soa_serial_changed) {
CHECK(increment_soa_serial(db, ver, &diff, mctx));
}
if (dns_db_issecure(db)) {
result = update_signatures(mctx, db, oldver, ver,
&diff, dns_zone_getsigvalidityinterval(zone));
if (result != ISC_R_SUCCESS) {
isc_log_write(ns_g_lctx, NS_LOGCATEGORY_UPDATE,
NS_LOGMODULE_UPDATE,
ISC_LOG_ERROR,
"SIG/NXT update failed: %s",
isc_result_totext(result));
goto failure;
}
}
isc_log_write(UPDATE_DEBUG_LOGARGS, "writing journal %s",
dns_zone_getjournal(zone));
journal = NULL;
result = dns_journal_open(mctx, dns_zone_getjournal(zone),
ISC_TRUE, &journal);
if (result != ISC_R_SUCCESS)
FAILS(result, "journal open failed");
result = dns_journal_write_transaction(journal, &diff);
if (result != ISC_R_SUCCESS) {
dns_journal_destroy(&journal);
FAILS(result, "journal write failed");
}
dns_journal_destroy(&journal);
}
/*
* XXXRTH Just a note that this committing code will have to change
* to handle databases that need two-phase commit, but this
* isn't a priority.
*/
isc_log_write(UPDATE_DEBUG_LOGARGS, "committing update transaction");
dns_db_closeversion(db, &ver, ISC_TRUE);
/*
* Notify slaves of the change we just made.
*/
dns_zone_notify(zone);
result = ISC_R_SUCCESS;
goto common;
failure:
/*
* The reason for failure should have been logged at this point.
*/
if (ver != NULL) {
isc_log_write(UPDATE_DEBUG_LOGARGS,
"rolling back");
dns_db_closeversion(db, &ver, ISC_FALSE);
}
common:
dns_diff_clear(&temp);
dns_diff_clear(&diff);
if (oldver != NULL)
dns_db_closeversion(db, &oldver, ISC_FALSE);
if (db != NULL)
dns_db_detach(&db);
if (zone != NULL)
dns_zone_detach(&zone);
isc_task_detach(&task);
uev->result = result;
uev->ev_type = DNS_EVENT_UPDATEDONE;
uev->ev_action = updatedone_action;
isc_task_send(client->task, &event);
INSIST(event == NULL);
}
static void
updatedone_action(isc_task_t *task, isc_event_t *event) {
update_event_t *uev = (update_event_t *) event;
ns_client_t *client = (ns_client_t *) event->ev_arg;
UNUSED(task);
INSIST(event->ev_type == DNS_EVENT_UPDATEDONE);
INSIST(task == client->task);
respond(client, uev->result);
ns_client_detach(&client);
isc_event_free(&event);
}