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Diffstat (limited to 'lib/dns/rbtdb.c')
| -rw-r--r-- | lib/dns/rbtdb.c | 6760 |
1 files changed, 6760 insertions, 0 deletions
diff --git a/lib/dns/rbtdb.c b/lib/dns/rbtdb.c new file mode 100644 index 0000000..1d729d0 --- /dev/null +++ b/lib/dns/rbtdb.c @@ -0,0 +1,6760 @@ +/* + * Copyright (C) 2004-2007 Internet Systems Consortium, Inc. ("ISC") + * Copyright (C) 1999-2003 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: rbtdb.c,v 1.196.18.48 2007/08/28 07:20:04 tbox Exp $ */ + +/*! \file */ + +/* + * Principal Author: Bob Halley + */ + +#include <config.h> + +#include <isc/event.h> +#include <isc/mem.h> +#include <isc/print.h> +#include <isc/mutex.h> +#include <isc/random.h> +#include <isc/refcount.h> +#include <isc/rwlock.h> +#include <isc/string.h> +#include <isc/task.h> +#include <isc/time.h> +#include <isc/util.h> + +#include <dns/acache.h> +#include <dns/db.h> +#include <dns/dbiterator.h> +#include <dns/events.h> +#include <dns/fixedname.h> +#include <dns/lib.h> +#include <dns/log.h> +#include <dns/masterdump.h> +#include <dns/rbt.h> +#include <dns/rdata.h> +#include <dns/rdataset.h> +#include <dns/rdatasetiter.h> +#include <dns/rdataslab.h> +#include <dns/result.h> +#include <dns/view.h> +#include <dns/zone.h> +#include <dns/zonekey.h> + +#ifdef DNS_RBTDB_VERSION64 +#include "rbtdb64.h" +#else +#include "rbtdb.h" +#endif + +#ifdef DNS_RBTDB_VERSION64 +#define RBTDB_MAGIC ISC_MAGIC('R', 'B', 'D', '8') +#else +#define RBTDB_MAGIC ISC_MAGIC('R', 'B', 'D', '4') +#endif + +/*% + * Note that "impmagic" is not the first four bytes of the struct, so + * ISC_MAGIC_VALID cannot be used. + */ +#define VALID_RBTDB(rbtdb) ((rbtdb) != NULL && \ + (rbtdb)->common.impmagic == RBTDB_MAGIC) + +#ifdef DNS_RBTDB_VERSION64 +typedef isc_uint64_t rbtdb_serial_t; +/*% + * Make casting easier in symbolic debuggers by using different names + * for the 64 bit version. + */ +#define dns_rbtdb_t dns_rbtdb64_t +#define rdatasetheader_t rdatasetheader64_t +#define rbtdb_version_t rbtdb_version64_t +#else +typedef isc_uint32_t rbtdb_serial_t; +#endif + +typedef isc_uint32_t rbtdb_rdatatype_t; + +#define RBTDB_RDATATYPE_BASE(type) ((dns_rdatatype_t)((type) & 0xFFFF)) +#define RBTDB_RDATATYPE_EXT(type) ((dns_rdatatype_t)((type) >> 16)) +#define RBTDB_RDATATYPE_VALUE(b, e) (((e) << 16) | (b)) + +#define RBTDB_RDATATYPE_SIGNSEC \ + RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, dns_rdatatype_nsec) +#define RBTDB_RDATATYPE_SIGNS \ + RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, dns_rdatatype_ns) +#define RBTDB_RDATATYPE_SIGCNAME \ + RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, dns_rdatatype_cname) +#define RBTDB_RDATATYPE_SIGDNAME \ + RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, dns_rdatatype_dname) +#define RBTDB_RDATATYPE_NCACHEANY \ + RBTDB_RDATATYPE_VALUE(0, dns_rdatatype_any) + +/* + * We use rwlock for DB lock only when ISC_RWLOCK_USEATOMIC is non 0. + * Using rwlock is effective with regard to lookup performance only when + * it is implemented in an efficient way. + * Otherwise, it is generally wise to stick to the simple locking since rwlock + * would require more memory or can even make lookups slower due to its own + * overhead (when it internally calls mutex locks). + */ +#ifdef ISC_RWLOCK_USEATOMIC +#define DNS_RBTDB_USERWLOCK 1 +#else +#define DNS_RBTDB_USERWLOCK 0 +#endif + +#if DNS_RBTDB_USERWLOCK +#define RBTDB_INITLOCK(l) isc_rwlock_init((l), 0, 0) +#define RBTDB_DESTROYLOCK(l) isc_rwlock_destroy(l) +#define RBTDB_LOCK(l, t) RWLOCK((l), (t)) +#define RBTDB_UNLOCK(l, t) RWUNLOCK((l), (t)) +#else +#define RBTDB_INITLOCK(l) isc_mutex_init(l) +#define RBTDB_DESTROYLOCK(l) DESTROYLOCK(l) +#define RBTDB_LOCK(l, t) LOCK(l) +#define RBTDB_UNLOCK(l, t) UNLOCK(l) +#endif + +/* + * Since node locking is sensitive to both performance and memory footprint, + * we need some trick here. If we have both high-performance rwlock and + * high performance and small-memory reference counters, we use rwlock for + * node lock and isc_refcount for node references. In this case, we don't have + * to protect the access to the counters by locks. + * Otherwise, we simply use ordinary mutex lock for node locking, and use + * simple integers as reference counters which is protected by the lock. + * In most cases, we can simply use wrapper macros such as NODE_LOCK and + * NODE_UNLOCK. In some other cases, however, we need to protect reference + * counters first and then protect other parts of a node as read-only data. + * Special additional macros, NODE_STRONGLOCK(), NODE_WEAKLOCK(), etc, are also + * provided for these special cases. When we can use the efficient backend + * routines, we should only protect the "other members" by NODE_WEAKLOCK(read). + * Otherwise, we should use NODE_STRONGLOCK() to protect the entire critical + * section including the access to the reference counter. + * Note that we cannot use NODE_LOCK()/NODE_UNLOCK() wherever the protected + * section is also protected by NODE_STRONGLOCK(). + */ +#if defined(ISC_RWLOCK_USEATOMIC) && defined(DNS_RBT_USEISCREFCOUNT) +typedef isc_rwlock_t nodelock_t; + +#define NODE_INITLOCK(l) isc_rwlock_init((l), 0, 0) +#define NODE_DESTROYLOCK(l) isc_rwlock_destroy(l) +#define NODE_LOCK(l, t) RWLOCK((l), (t)) +#define NODE_UNLOCK(l, t) RWUNLOCK((l), (t)) +#define NODE_TRYUPGRADE(l) isc_rwlock_tryupgrade(l) + +#define NODE_STRONGLOCK(l) ((void)0) +#define NODE_STRONGUNLOCK(l) ((void)0) +#define NODE_WEAKLOCK(l, t) NODE_LOCK(l, t) +#define NODE_WEAKUNLOCK(l, t) NODE_UNLOCK(l, t) +#define NODE_WEAKDOWNGRADE(l) isc_rwlock_downgrade(l) +#else +typedef isc_mutex_t nodelock_t; + +#define NODE_INITLOCK(l) isc_mutex_init(l) +#define NODE_DESTROYLOCK(l) DESTROYLOCK(l) +#define NODE_LOCK(l, t) LOCK(l) +#define NODE_UNLOCK(l, t) UNLOCK(l) +#define NODE_TRYUPGRADE(l) ISC_R_SUCCESS + +#define NODE_STRONGLOCK(l) LOCK(l) +#define NODE_STRONGUNLOCK(l) UNLOCK(l) +#define NODE_WEAKLOCK(l, t) ((void)0) +#define NODE_WEAKUNLOCK(l, t) ((void)0) +#define NODE_WEAKDOWNGRADE(l) ((void)0) +#endif + +#ifndef DNS_RDATASET_FIXED +#define DNS_RDATASET_FIXED 1 +#endif + +/* + * Allow clients with a virtual time of upto 5 minutes in the past to see + * records that would have otherwise have expired. + */ +#define RBTDB_VIRTUAL 300 + +struct noqname { + dns_name_t name; + void * nsec; + void * nsecsig; +}; + +typedef struct acachectl acachectl_t; + +typedef struct rdatasetheader { + /*% + * Locked by the owning node's lock. + */ + rbtdb_serial_t serial; + dns_ttl_t ttl; + rbtdb_rdatatype_t type; + isc_uint16_t attributes; + dns_trust_t trust; + struct noqname *noqname; + /*%< + * We don't use the LIST macros, because the LIST structure has + * both head and tail pointers, and is doubly linked. + */ + + struct rdatasetheader *next; + /*%< + * If this is the top header for an rdataset, 'next' points + * to the top header for the next rdataset (i.e., the next type). + * Otherwise, it points up to the header whose down pointer points + * at this header. + */ + + struct rdatasetheader *down; + /*%< + * Points to the header for the next older version of + * this rdataset. + */ + + isc_uint32_t count; + /*%< + * Monotonously increased every time this rdataset is bound so that + * it is used as the base of the starting point in DNS responses + * when the "cyclic" rrset-order is required. Since the ordering + * should not be so crucial, no lock is set for the counter for + * performance reasons. + */ + + acachectl_t *additional_auth; + acachectl_t *additional_glue; +} rdatasetheader_t; + +#define RDATASET_ATTR_NONEXISTENT 0x0001 +#define RDATASET_ATTR_STALE 0x0002 +#define RDATASET_ATTR_IGNORE 0x0004 +#define RDATASET_ATTR_RETAIN 0x0008 +#define RDATASET_ATTR_NXDOMAIN 0x0010 + +typedef struct acache_cbarg { + dns_rdatasetadditional_t type; + unsigned int count; + dns_db_t *db; + dns_dbnode_t *node; + rdatasetheader_t *header; +} acache_cbarg_t; + +struct acachectl { + dns_acacheentry_t *entry; + acache_cbarg_t *cbarg; +}; + +/* + * XXX + * When the cache will pre-expire data (due to memory low or other + * situations) before the rdataset's TTL has expired, it MUST + * respect the RETAIN bit and not expire the data until its TTL is + * expired. + */ + +#undef IGNORE /* WIN32 winbase.h defines this. */ + +#define EXISTS(header) \ + (((header)->attributes & RDATASET_ATTR_NONEXISTENT) == 0) +#define NONEXISTENT(header) \ + (((header)->attributes & RDATASET_ATTR_NONEXISTENT) != 0) +#define IGNORE(header) \ + (((header)->attributes & RDATASET_ATTR_IGNORE) != 0) +#define RETAIN(header) \ + (((header)->attributes & RDATASET_ATTR_RETAIN) != 0) +#define NXDOMAIN(header) \ + (((header)->attributes & RDATASET_ATTR_NXDOMAIN) != 0) + +#define DEFAULT_NODE_LOCK_COUNT 7 /*%< Should be prime. */ +#define DEFAULT_CACHE_NODE_LOCK_COUNT 1009 /*%< Should be prime. */ + +typedef struct { + nodelock_t lock; + /* Protected in the refcount routines. */ + isc_refcount_t references; + /* Locked by lock. */ + isc_boolean_t exiting; +} rbtdb_nodelock_t; + +typedef struct rbtdb_changed { + dns_rbtnode_t * node; + isc_boolean_t dirty; + ISC_LINK(struct rbtdb_changed) link; +} rbtdb_changed_t; + +typedef ISC_LIST(rbtdb_changed_t) rbtdb_changedlist_t; + +typedef struct rbtdb_version { + /* Not locked */ + rbtdb_serial_t serial; + /* + * Protected in the refcount routines. + * XXXJT: should we change the lock policy based on the refcount + * performance? + */ + isc_refcount_t references; + /* Locked by database lock. */ + isc_boolean_t writer; + isc_boolean_t commit_ok; + rbtdb_changedlist_t changed_list; + ISC_LINK(struct rbtdb_version) link; +} rbtdb_version_t; + +typedef ISC_LIST(rbtdb_version_t) rbtdb_versionlist_t; + +typedef struct { + /* Unlocked. */ + dns_db_t common; +#if DNS_RBTDB_USERWLOCK + isc_rwlock_t lock; +#else + isc_mutex_t lock; +#endif + isc_rwlock_t tree_lock; + unsigned int node_lock_count; + rbtdb_nodelock_t * node_locks; + dns_rbtnode_t * origin_node; + /* Locked by lock. */ + unsigned int active; + isc_refcount_t references; + unsigned int attributes; + rbtdb_serial_t current_serial; + rbtdb_serial_t least_serial; + rbtdb_serial_t next_serial; + rbtdb_version_t * current_version; + rbtdb_version_t * future_version; + rbtdb_versionlist_t open_versions; + isc_boolean_t overmem; + isc_task_t * task; + dns_dbnode_t *soanode; + dns_dbnode_t *nsnode; + /* Locked by tree_lock. */ + dns_rbt_t * tree; + isc_boolean_t secure; + + /* Unlocked */ + unsigned int quantum; +} dns_rbtdb_t; + +#define RBTDB_ATTR_LOADED 0x01 +#define RBTDB_ATTR_LOADING 0x02 + +/*% + * Search Context + */ +typedef struct { + dns_rbtdb_t * rbtdb; + rbtdb_version_t * rbtversion; + rbtdb_serial_t serial; + unsigned int options; + dns_rbtnodechain_t chain; + isc_boolean_t copy_name; + isc_boolean_t need_cleanup; + isc_boolean_t wild; + dns_rbtnode_t * zonecut; + rdatasetheader_t * zonecut_rdataset; + rdatasetheader_t * zonecut_sigrdataset; + dns_fixedname_t zonecut_name; + isc_stdtime_t now; +} rbtdb_search_t; + +/*% + * Load Context + */ +typedef struct { + dns_rbtdb_t * rbtdb; + isc_stdtime_t now; +} rbtdb_load_t; + +static void rdataset_disassociate(dns_rdataset_t *rdataset); +static isc_result_t rdataset_first(dns_rdataset_t *rdataset); +static isc_result_t rdataset_next(dns_rdataset_t *rdataset); +static void rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata); +static void rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target); +static unsigned int rdataset_count(dns_rdataset_t *rdataset); +static isc_result_t rdataset_getnoqname(dns_rdataset_t *rdataset, + dns_name_t *name, + dns_rdataset_t *nsec, + dns_rdataset_t *nsecsig); +static isc_result_t rdataset_getadditional(dns_rdataset_t *rdataset, + dns_rdatasetadditional_t type, + dns_rdatatype_t qtype, + dns_acache_t *acache, + dns_zone_t **zonep, + dns_db_t **dbp, + dns_dbversion_t **versionp, + dns_dbnode_t **nodep, + dns_name_t *fname, + dns_message_t *msg, + isc_stdtime_t now); +static isc_result_t rdataset_setadditional(dns_rdataset_t *rdataset, + dns_rdatasetadditional_t type, + dns_rdatatype_t qtype, + dns_acache_t *acache, + dns_zone_t *zone, + dns_db_t *db, + dns_dbversion_t *version, + dns_dbnode_t *node, + dns_name_t *fname); +static isc_result_t rdataset_putadditional(dns_acache_t *acache, + dns_rdataset_t *rdataset, + dns_rdatasetadditional_t type, + dns_rdatatype_t qtype); + +static dns_rdatasetmethods_t rdataset_methods = { + rdataset_disassociate, + rdataset_first, + rdataset_next, + rdataset_current, + rdataset_clone, + rdataset_count, + NULL, + rdataset_getnoqname, + rdataset_getadditional, + rdataset_setadditional, + rdataset_putadditional +}; + +static void rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp); +static isc_result_t rdatasetiter_first(dns_rdatasetiter_t *iterator); +static isc_result_t rdatasetiter_next(dns_rdatasetiter_t *iterator); +static void rdatasetiter_current(dns_rdatasetiter_t *iterator, + dns_rdataset_t *rdataset); + +static dns_rdatasetitermethods_t rdatasetiter_methods = { + rdatasetiter_destroy, + rdatasetiter_first, + rdatasetiter_next, + rdatasetiter_current +}; + +typedef struct rbtdb_rdatasetiter { + dns_rdatasetiter_t common; + rdatasetheader_t * current; +} rbtdb_rdatasetiter_t; + +static void dbiterator_destroy(dns_dbiterator_t **iteratorp); +static isc_result_t dbiterator_first(dns_dbiterator_t *iterator); +static isc_result_t dbiterator_last(dns_dbiterator_t *iterator); +static isc_result_t dbiterator_seek(dns_dbiterator_t *iterator, + dns_name_t *name); +static isc_result_t dbiterator_prev(dns_dbiterator_t *iterator); +static isc_result_t dbiterator_next(dns_dbiterator_t *iterator); +static isc_result_t dbiterator_current(dns_dbiterator_t *iterator, + dns_dbnode_t **nodep, + dns_name_t *name); +static isc_result_t dbiterator_pause(dns_dbiterator_t *iterator); +static isc_result_t dbiterator_origin(dns_dbiterator_t *iterator, + dns_name_t *name); + +static dns_dbiteratormethods_t dbiterator_methods = { + dbiterator_destroy, + dbiterator_first, + dbiterator_last, + dbiterator_seek, + dbiterator_prev, + dbiterator_next, + dbiterator_current, + dbiterator_pause, + dbiterator_origin +}; + +#define DELETION_BATCH_MAX 64 + +/* + * If 'paused' is ISC_TRUE, then the tree lock is not being held. + */ +typedef struct rbtdb_dbiterator { + dns_dbiterator_t common; + isc_boolean_t paused; + isc_boolean_t new_origin; + isc_rwlocktype_t tree_locked; + isc_result_t result; + dns_fixedname_t name; + dns_fixedname_t origin; + dns_rbtnodechain_t chain; + dns_rbtnode_t *node; + dns_rbtnode_t *deletions[DELETION_BATCH_MAX]; + int delete; +} rbtdb_dbiterator_t; + + +#define IS_STUB(rbtdb) (((rbtdb)->common.attributes & DNS_DBATTR_STUB) != 0) +#define IS_CACHE(rbtdb) (((rbtdb)->common.attributes & DNS_DBATTR_CACHE) != 0) + +static void free_rbtdb(dns_rbtdb_t *rbtdb, isc_boolean_t log, + isc_event_t *event); + +/*% + * 'init_count' is used to initialize 'newheader->count' which inturn + * is used to determine where in the cycle rrset-order cyclic starts. + * We don't lock this as we don't care about simultanious updates. + * + * Note: + * Both init_count and header->count can be ISC_UINT32_MAX. + * The count on the returned rdataset however can't be as + * that indicates that the database does not implement cyclic + * processing. + */ +static unsigned int init_count; + +/* + * Locking + * + * If a routine is going to lock more than one lock in this module, then + * the locking must be done in the following order: + * + * Tree Lock + * + * Node Lock (Only one from the set may be locked at one time by + * any caller) + * + * Database Lock + * + * Failure to follow this hierarchy can result in deadlock. + */ + +/* + * Deleting Nodes + * + * Currently there is no deletion of nodes from the database, except when + * the database is being destroyed. + * + * If node deletion is added in the future, then for zone databases the node + * for the origin of the zone MUST NOT be deleted. + */ + + +/* + * DB Routines + */ + +static void +attach(dns_db_t *source, dns_db_t **targetp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)source; + + REQUIRE(VALID_RBTDB(rbtdb)); + + isc_refcount_increment(&rbtdb->references, NULL); + + *targetp = source; +} + +static void +free_rbtdb_callback(isc_task_t *task, isc_event_t *event) { + dns_rbtdb_t *rbtdb = event->ev_arg; + + UNUSED(task); + + free_rbtdb(rbtdb, ISC_TRUE, event); +} + +/*% + * Work out how many nodes can be deleted in the time between two + * requests to the nameserver. Smooth the resulting number and use it + * as a estimate for the number of nodes to be deleted in the next + * iteration. + */ +static unsigned int +adjust_quantum(unsigned int old, isc_time_t *start) { + unsigned int pps = dns_pps; /* packets per second */ + unsigned int interval; + isc_uint64_t usecs; + isc_time_t end; + unsigned int new; + + if (pps < 100) + pps = 100; + isc_time_now(&end); + + interval = 1000000 / pps; /* interval in usec */ + if (interval == 0) + interval = 1; + usecs = isc_time_microdiff(&end, start); + if (usecs == 0) { + /* + * We were unable to measure the amount of time taken. + * Double the nodes deleted next time. + */ + old *= 2; + if (old > 1000) + old = 1000; + return (old); + } + new = old * interval; + new /= (unsigned int)usecs; + if (new == 0) + new = 1; + else if (new > 1000) + new = 1000; + + /* Smooth */ + new = (new + old * 3) / 4; + + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_CACHE, + ISC_LOG_DEBUG(1), "adjust_quantum -> %d", new); + + return (new); +} + +static void +free_rbtdb(dns_rbtdb_t *rbtdb, isc_boolean_t log, isc_event_t *event) { + unsigned int i; + isc_ondestroy_t ondest; + isc_result_t result; + char buf[DNS_NAME_FORMATSIZE]; + isc_time_t start; + + REQUIRE(rbtdb->current_version != NULL || EMPTY(rbtdb->open_versions)); + REQUIRE(rbtdb->future_version == NULL); + + if (rbtdb->current_version != NULL) { + unsigned int refs; + + isc_refcount_decrement(&rbtdb->current_version->references, + &refs); + INSIST(refs == 0); + UNLINK(rbtdb->open_versions, rbtdb->current_version, link); + isc_refcount_destroy(&rbtdb->current_version->references); + isc_mem_put(rbtdb->common.mctx, rbtdb->current_version, + sizeof(rbtdb_version_t)); + } + if (event == NULL) + rbtdb->quantum = (rbtdb->task != NULL) ? 100 : 0; + again: + if (rbtdb->tree != NULL) { + isc_time_now(&start); + result = dns_rbt_destroy2(&rbtdb->tree, rbtdb->quantum); + if (result == ISC_R_QUOTA) { + INSIST(rbtdb->task != NULL); + if (rbtdb->quantum != 0) + rbtdb->quantum = adjust_quantum(rbtdb->quantum, + &start); + if (event == NULL) + event = isc_event_allocate(rbtdb->common.mctx, + NULL, + DNS_EVENT_FREESTORAGE, + free_rbtdb_callback, + rbtdb, + sizeof(isc_event_t)); + if (event == NULL) + goto again; + isc_task_send(rbtdb->task, &event); + return; + } + INSIST(result == ISC_R_SUCCESS && rbtdb->tree == NULL); + } + if (event != NULL) + isc_event_free(&event); + if (log) { + if (dns_name_dynamic(&rbtdb->common.origin)) + dns_name_format(&rbtdb->common.origin, buf, + sizeof(buf)); + else + strcpy(buf, "<UNKNOWN>"); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_DEBUG(1), + "done free_rbtdb(%s)", buf); + } + if (dns_name_dynamic(&rbtdb->common.origin)) + dns_name_free(&rbtdb->common.origin, rbtdb->common.mctx); + for (i = 0; i < rbtdb->node_lock_count; i++) { + isc_refcount_destroy(&rbtdb->node_locks[i].references); + NODE_DESTROYLOCK(&rbtdb->node_locks[i].lock); + } + isc_mem_put(rbtdb->common.mctx, rbtdb->node_locks, + rbtdb->node_lock_count * sizeof(rbtdb_nodelock_t)); + isc_rwlock_destroy(&rbtdb->tree_lock); + isc_refcount_destroy(&rbtdb->references); + if (rbtdb->task != NULL) + isc_task_detach(&rbtdb->task); + RBTDB_DESTROYLOCK(&rbtdb->lock); + rbtdb->common.magic = 0; + rbtdb->common.impmagic = 0; + ondest = rbtdb->common.ondest; + isc_mem_putanddetach(&rbtdb->common.mctx, rbtdb, sizeof(*rbtdb)); + isc_ondestroy_notify(&ondest, rbtdb); +} + +static inline void +maybe_free_rbtdb(dns_rbtdb_t *rbtdb) { + isc_boolean_t want_free = ISC_FALSE; + unsigned int i; + unsigned int inactive = 0; + + /* XXX check for open versions here */ + + if (rbtdb->soanode != NULL) + dns_db_detachnode((dns_db_t *)rbtdb, &rbtdb->soanode); + if (rbtdb->nsnode != NULL) + dns_db_detachnode((dns_db_t *)rbtdb, &rbtdb->nsnode); + + /* + * Even though there are no external direct references, there still + * may be nodes in use. + */ + for (i = 0; i < rbtdb->node_lock_count; i++) { + NODE_LOCK(&rbtdb->node_locks[i].lock, isc_rwlocktype_write); + rbtdb->node_locks[i].exiting = ISC_TRUE; + NODE_UNLOCK(&rbtdb->node_locks[i].lock, isc_rwlocktype_write); + if (isc_refcount_current(&rbtdb->node_locks[i].references) + == 0) { + inactive++; + } + } + + if (inactive != 0) { + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + rbtdb->active -= inactive; + if (rbtdb->active == 0) + want_free = ISC_TRUE; + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + if (want_free) { + char buf[DNS_NAME_FORMATSIZE]; + if (dns_name_dynamic(&rbtdb->common.origin)) + dns_name_format(&rbtdb->common.origin, buf, + sizeof(buf)); + else + strcpy(buf, "<UNKNOWN>"); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_DEBUG(1), + "calling free_rbtdb(%s)", buf); + free_rbtdb(rbtdb, ISC_TRUE, NULL); + } + } +} + +static void +detach(dns_db_t **dbp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)(*dbp); + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + + isc_refcount_decrement(&rbtdb->references, &refs); + + if (refs == 0) + maybe_free_rbtdb(rbtdb); + + *dbp = NULL; +} + +static void +currentversion(dns_db_t *db, dns_dbversion_t **versionp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + rbtdb_version_t *version; + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_read); + version = rbtdb->current_version; + isc_refcount_increment(&version->references, &refs); + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_read); + + *versionp = (dns_dbversion_t *)version; +} + +static inline rbtdb_version_t * +allocate_version(isc_mem_t *mctx, rbtdb_serial_t serial, + unsigned int references, isc_boolean_t writer) +{ + isc_result_t result; + rbtdb_version_t *version; + + version = isc_mem_get(mctx, sizeof(*version)); + if (version == NULL) + return (NULL); + version->serial = serial; + result = isc_refcount_init(&version->references, references); + if (result != ISC_R_SUCCESS) { + isc_mem_put(mctx, version, sizeof(*version)); + return (NULL); + } + version->writer = writer; + version->commit_ok = ISC_FALSE; + ISC_LIST_INIT(version->changed_list); + ISC_LINK_INIT(version, link); + + return (version); +} + +static isc_result_t +newversion(dns_db_t *db, dns_dbversion_t **versionp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + rbtdb_version_t *version; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(versionp != NULL && *versionp == NULL); + REQUIRE(rbtdb->future_version == NULL); + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + RUNTIME_CHECK(rbtdb->next_serial != 0); /* XXX Error? */ + version = allocate_version(rbtdb->common.mctx, rbtdb->next_serial, 1, + ISC_TRUE); + if (version != NULL) { + version->commit_ok = ISC_TRUE; + rbtdb->next_serial++; + rbtdb->future_version = version; + } + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + + if (version == NULL) + return (ISC_R_NOMEMORY); + + *versionp = version; + + return (ISC_R_SUCCESS); +} + +static void +attachversion(dns_db_t *db, dns_dbversion_t *source, + dns_dbversion_t **targetp) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + rbtdb_version_t *rbtversion = source; + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + + isc_refcount_increment(&rbtversion->references, &refs); + INSIST(refs > 1); + + *targetp = rbtversion; +} + +static rbtdb_changed_t * +add_changed(dns_rbtdb_t *rbtdb, rbtdb_version_t *version, + dns_rbtnode_t *node) +{ + rbtdb_changed_t *changed; + unsigned int refs; + + /* + * Caller must be holding the node lock if its reference must be + * protected by the lock. + */ + + changed = isc_mem_get(rbtdb->common.mctx, sizeof(*changed)); + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + + REQUIRE(version->writer); + + if (changed != NULL) { + dns_rbtnode_refincrement(node, &refs); + INSIST(refs != 0); + changed->node = node; + changed->dirty = ISC_FALSE; + ISC_LIST_INITANDAPPEND(version->changed_list, changed, link); + } else + version->commit_ok = ISC_FALSE; + + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + + return (changed); +} + +static void +free_acachearray(isc_mem_t *mctx, rdatasetheader_t *header, + acachectl_t *array) +{ + unsigned int count; + unsigned int i; + unsigned char *raw; /* RDATASLAB */ + + /* + * The caller must be holding the corresponding node lock. + */ + + if (array == NULL) + return; + + raw = (unsigned char *)header + sizeof(*header); + count = raw[0] * 256 + raw[1]; + + /* + * Sanity check: since an additional cache entry has a reference to + * the original DB node (in the callback arg), there should be no + * acache entries when the node can be freed. + */ + for (i = 0; i < count; i++) + INSIST(array[i].entry == NULL && array[i].cbarg == NULL); + + isc_mem_put(mctx, array, count * sizeof(acachectl_t)); +} + +static inline void +free_noqname(isc_mem_t *mctx, struct noqname **noqname) { + + if (dns_name_dynamic(&(*noqname)->name)) + dns_name_free(&(*noqname)->name, mctx); + if ((*noqname)->nsec != NULL) + isc_mem_put(mctx, (*noqname)->nsec, + dns_rdataslab_size((*noqname)->nsec, 0)); + if ((*noqname)->nsecsig != NULL) + isc_mem_put(mctx, (*noqname)->nsecsig, + dns_rdataslab_size((*noqname)->nsecsig, 0)); + isc_mem_put(mctx, *noqname, sizeof(**noqname)); + *noqname = NULL; +} + +static inline void +free_rdataset(isc_mem_t *mctx, rdatasetheader_t *rdataset) { + unsigned int size; + + if (rdataset->noqname != NULL) + free_noqname(mctx, &rdataset->noqname); + + free_acachearray(mctx, rdataset, rdataset->additional_auth); + free_acachearray(mctx, rdataset, rdataset->additional_glue); + + if ((rdataset->attributes & RDATASET_ATTR_NONEXISTENT) != 0) + size = sizeof(*rdataset); + else + size = dns_rdataslab_size((unsigned char *)rdataset, + sizeof(*rdataset)); + isc_mem_put(mctx, rdataset, size); +} + +static inline void +rollback_node(dns_rbtnode_t *node, rbtdb_serial_t serial) { + rdatasetheader_t *header, *dcurrent; + isc_boolean_t make_dirty = ISC_FALSE; + + /* + * Caller must hold the node lock. + */ + + /* + * We set the IGNORE attribute on rdatasets with serial number + * 'serial'. When the reference count goes to zero, these rdatasets + * will be cleaned up; until that time, they will be ignored. + */ + for (header = node->data; header != NULL; header = header->next) { + if (header->serial == serial) { + header->attributes |= RDATASET_ATTR_IGNORE; + make_dirty = ISC_TRUE; + } + for (dcurrent = header->down; + dcurrent != NULL; + dcurrent = dcurrent->down) { + if (dcurrent->serial == serial) { + dcurrent->attributes |= RDATASET_ATTR_IGNORE; + make_dirty = ISC_TRUE; + } + } + } + if (make_dirty) + node->dirty = 1; +} + +static inline void +clean_stale_headers(isc_mem_t *mctx, rdatasetheader_t *top) { + rdatasetheader_t *d, *down_next; + + for (d = top->down; d != NULL; d = down_next) { + down_next = d->down; + free_rdataset(mctx, d); + } + top->down = NULL; +} + +static inline void +clean_cache_node(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node) { + rdatasetheader_t *current, *top_prev, *top_next; + isc_mem_t *mctx = rbtdb->common.mctx; + + /* + * Caller must be holding the node lock. + */ + + top_prev = NULL; + for (current = node->data; current != NULL; current = top_next) { + top_next = current->next; + clean_stale_headers(mctx, current); + /* + * If current is nonexistent or stale, we can clean it up. + */ + if ((current->attributes & + (RDATASET_ATTR_NONEXISTENT|RDATASET_ATTR_STALE)) != 0) { + if (top_prev != NULL) + top_prev->next = current->next; + else + node->data = current->next; + free_rdataset(mctx, current); + } else + top_prev = current; + } + node->dirty = 0; +} + +static inline void +clean_zone_node(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, + rbtdb_serial_t least_serial) +{ + rdatasetheader_t *current, *dcurrent, *down_next, *dparent; + rdatasetheader_t *top_prev, *top_next; + isc_mem_t *mctx = rbtdb->common.mctx; + isc_boolean_t still_dirty = ISC_FALSE; + + /* + * Caller must be holding the node lock. + */ + REQUIRE(least_serial != 0); + + top_prev = NULL; + for (current = node->data; current != NULL; current = top_next) { + top_next = current->next; + + /* + * First, we clean up any instances of multiple rdatasets + * with the same serial number, or that have the IGNORE + * attribute. + */ + dparent = current; + for (dcurrent = current->down; + dcurrent != NULL; + dcurrent = down_next) { + down_next = dcurrent->down; + INSIST(dcurrent->serial <= dparent->serial); + if (dcurrent->serial == dparent->serial || + IGNORE(dcurrent)) { + if (down_next != NULL) + down_next->next = dparent; + dparent->down = down_next; + free_rdataset(mctx, dcurrent); + } else + dparent = dcurrent; + } + + /* + * We've now eliminated all IGNORE datasets with the possible + * exception of current, which we now check. + */ + if (IGNORE(current)) { + down_next = current->down; + if (down_next == NULL) { + if (top_prev != NULL) + top_prev->next = current->next; + else + node->data = current->next; + free_rdataset(mctx, current); + /* + * current no longer exists, so we can + * just continue with the loop. + */ + continue; + } else { + /* + * Pull up current->down, making it the new + * current. + */ + if (top_prev != NULL) + top_prev->next = down_next; + else + node->data = down_next; + down_next->next = top_next; + free_rdataset(mctx, current); + current = down_next; + } + } + + /* + * We now try to find the first down node less than the + * least serial. + */ + dparent = current; + for (dcurrent = current->down; + dcurrent != NULL; + dcurrent = down_next) { + down_next = dcurrent->down; + if (dcurrent->serial < least_serial) + break; + dparent = dcurrent; + } + + /* + * If there is a such an rdataset, delete it and any older + * versions. + */ + if (dcurrent != NULL) { + do { + down_next = dcurrent->down; + INSIST(dcurrent->serial <= least_serial); + free_rdataset(mctx, dcurrent); + dcurrent = down_next; + } while (dcurrent != NULL); + dparent->down = NULL; + } + + /* + * Note. The serial number of 'current' might be less than + * least_serial too, but we cannot delete it because it is + * the most recent version, unless it is a NONEXISTENT + * rdataset. + */ + if (current->down != NULL) { + still_dirty = ISC_TRUE; + top_prev = current; + } else { + /* + * If this is a NONEXISTENT rdataset, we can delete it. + */ + if (NONEXISTENT(current)) { + if (top_prev != NULL) + top_prev->next = current->next; + else + node->data = current->next; + free_rdataset(mctx, current); + } else + top_prev = current; + } + } + if (!still_dirty) + node->dirty = 0; +} + +/* + * Caller must be holding the node lock if its reference must be protected + * by the lock. + */ +static inline void +new_reference(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node) { + unsigned int lockrefs, noderefs; + isc_refcount_t *lockref; + + dns_rbtnode_refincrement0(node, &noderefs); + if (noderefs == 1) { /* this is the first reference to the node */ + lockref = &rbtdb->node_locks[node->locknum].references; + isc_refcount_increment0(lockref, &lockrefs); + INSIST(lockrefs != 0); + } + INSIST(noderefs != 0); +} + +/* + * Caller must be holding the node lock; either the "strong", read or write + * lock. Note that the lock must be held even when node references are + * atomically modified; in that case the decrement operation itself does not + * have to be protected, but we must avoid a race condition where multiple + * threads are decreasing the reference to zero simultaneously and at least + * one of them is going to free the node. + * This function returns ISC_TRUE if and only if the node reference decreases + * to zero. + */ +static isc_boolean_t +decrement_reference(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, + rbtdb_serial_t least_serial, + isc_rwlocktype_t nlock, isc_rwlocktype_t tlock) +{ + isc_result_t result; + isc_boolean_t write_locked; + rbtdb_nodelock_t *nodelock; + unsigned int refs, nrefs; + + nodelock = &rbtdb->node_locks[node->locknum]; + + /* Handle easy and typical case first. */ + if (!node->dirty && (node->data != NULL || node->down != NULL)) { + dns_rbtnode_refdecrement(node, &nrefs); + INSIST((int)nrefs >= 0); + if (nrefs == 0) { + isc_refcount_decrement(&nodelock->references, &refs); + INSIST((int)refs >= 0); + } + return ((nrefs == 0) ? ISC_TRUE : ISC_FALSE); + } + + /* Upgrade the lock? */ + if (nlock == isc_rwlocktype_read) { + NODE_WEAKUNLOCK(&nodelock->lock, isc_rwlocktype_read); + NODE_WEAKLOCK(&nodelock->lock, isc_rwlocktype_write); + } + dns_rbtnode_refdecrement(node, &nrefs); + INSIST((int)nrefs >= 0); + if (nrefs > 0) { + /* Restore the lock? */ + if (nlock == isc_rwlocktype_read) + NODE_WEAKDOWNGRADE(&nodelock->lock); + return (ISC_FALSE); + } + + if (node->dirty && dns_rbtnode_refcurrent(node) == 0) { + if (IS_CACHE(rbtdb)) + clean_cache_node(rbtdb, node); + else { + if (least_serial == 0) { + /* + * Caller doesn't know the least serial. + * Get it. + */ + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_read); + least_serial = rbtdb->least_serial; + RBTDB_UNLOCK(&rbtdb->lock, + isc_rwlocktype_read); + } + clean_zone_node(rbtdb, node, least_serial); + } + } + + isc_refcount_decrement(&nodelock->references, &refs); + INSIST((int)refs >= 0); + + /* + * XXXDCL should this only be done for cache zones? + */ + if (node->data != NULL || node->down != NULL) { + /* Restore the lock? */ + if (nlock == isc_rwlocktype_read) + NODE_WEAKDOWNGRADE(&nodelock->lock); + return (ISC_TRUE); + } + + /* + * XXXDCL need to add a deferred delete method for ISC_R_LOCKBUSY. + */ + if (tlock != isc_rwlocktype_write) { + /* + * Locking hierarchy notwithstanding, we don't need to free + * the node lock before acquiring the tree write lock because + * we only do a trylock. + */ + if (tlock == isc_rwlocktype_read) + result = isc_rwlock_tryupgrade(&rbtdb->tree_lock); + else + result = isc_rwlock_trylock(&rbtdb->tree_lock, + isc_rwlocktype_write); + RUNTIME_CHECK(result == ISC_R_SUCCESS || + result == ISC_R_LOCKBUSY); + + write_locked = ISC_TF(result == ISC_R_SUCCESS); + } else + write_locked = ISC_TRUE; + + if (write_locked && dns_rbtnode_refcurrent(node) == 0) { + /* + * We can now delete the node if the reference counter is + * zero. This should be typically the case, but a different + * thread may still gain a (new) reference just before the + * current thread locks the tree (e.g., in findnode()). + */ + + if (isc_log_wouldlog(dns_lctx, ISC_LOG_DEBUG(1))) { + char printname[DNS_NAME_FORMATSIZE]; + + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_DEBUG(1), + "decrement_reference: " + "delete from rbt: %p %s", + node, + dns_rbt_formatnodename(node, printname, + sizeof(printname))); + } + + result = dns_rbt_deletenode(rbtdb->tree, node, ISC_FALSE); + if (result != ISC_R_SUCCESS) + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_WARNING, + "decrement_reference: " + "dns_rbt_deletenode: %s", + isc_result_totext(result)); + } + + /* Restore the lock? */ + if (nlock == isc_rwlocktype_read) + NODE_WEAKDOWNGRADE(&nodelock->lock); + + /* + * Relock a read lock, or unlock the write lock if no lock was held. + */ + if (tlock == isc_rwlocktype_none) + if (write_locked) + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_write); + + if (tlock == isc_rwlocktype_read) + if (write_locked) + isc_rwlock_downgrade(&rbtdb->tree_lock); + + return (ISC_TRUE); +} + +static inline void +make_least_version(dns_rbtdb_t *rbtdb, rbtdb_version_t *version, + rbtdb_changedlist_t *cleanup_list) +{ + /* + * Caller must be holding the database lock. + */ + + rbtdb->least_serial = version->serial; + *cleanup_list = version->changed_list; + ISC_LIST_INIT(version->changed_list); +} + +static inline void +cleanup_nondirty(rbtdb_version_t *version, rbtdb_changedlist_t *cleanup_list) { + rbtdb_changed_t *changed, *next_changed; + + /* + * If the changed record is dirty, then + * an update created multiple versions of + * a given rdataset. We keep this list + * until we're the least open version, at + * which point it's safe to get rid of any + * older versions. + * + * If the changed record isn't dirty, then + * we don't need it anymore since we're + * committing and not rolling back. + * + * The caller must be holding the database lock. + */ + for (changed = HEAD(version->changed_list); + changed != NULL; + changed = next_changed) { + next_changed = NEXT(changed, link); + if (!changed->dirty) { + UNLINK(version->changed_list, + changed, link); + APPEND(*cleanup_list, + changed, link); + } + } +} + +static isc_boolean_t +iszonesecure(dns_db_t *db, dns_dbnode_t *origin) { + dns_rdataset_t keyset; + dns_rdataset_t nsecset, signsecset; + isc_boolean_t haszonekey = ISC_FALSE; + isc_boolean_t hasnsec = ISC_FALSE; + isc_result_t result; + + dns_rdataset_init(&keyset); + result = dns_db_findrdataset(db, origin, NULL, dns_rdatatype_dnskey, 0, + 0, &keyset, NULL); + if (result == ISC_R_SUCCESS) { + dns_rdata_t keyrdata = DNS_RDATA_INIT; + result = dns_rdataset_first(&keyset); + while (result == ISC_R_SUCCESS) { + dns_rdataset_current(&keyset, &keyrdata); + if (dns_zonekey_iszonekey(&keyrdata)) { + haszonekey = ISC_TRUE; + break; + } + result = dns_rdataset_next(&keyset); + } + dns_rdataset_disassociate(&keyset); + } + if (!haszonekey) + return (ISC_FALSE); + + dns_rdataset_init(&nsecset); + dns_rdataset_init(&signsecset); + result = dns_db_findrdataset(db, origin, NULL, dns_rdatatype_nsec, 0, + 0, &nsecset, &signsecset); + if (result == ISC_R_SUCCESS) { + if (dns_rdataset_isassociated(&signsecset)) { + hasnsec = ISC_TRUE; + dns_rdataset_disassociate(&signsecset); + } + dns_rdataset_disassociate(&nsecset); + } + return (hasnsec); +} + +static void +closeversion(dns_db_t *db, dns_dbversion_t **versionp, isc_boolean_t commit) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + rbtdb_version_t *version, *cleanup_version, *least_greater; + isc_boolean_t rollback = ISC_FALSE; + rbtdb_changedlist_t cleanup_list; + rbtdb_changed_t *changed, *next_changed; + rbtdb_serial_t serial, least_serial; + dns_rbtnode_t *rbtnode; + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + version = (rbtdb_version_t *)*versionp; + + cleanup_version = NULL; + ISC_LIST_INIT(cleanup_list); + + isc_refcount_decrement(&version->references, &refs); + if (refs > 0) { /* typical and easy case first */ + if (commit) { + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_read); + INSIST(!version->writer); + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_read); + } + goto end; + } + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + serial = version->serial; + if (version->writer) { + if (commit) { + unsigned cur_ref; + rbtdb_version_t *cur_version; + + INSIST(version->commit_ok); + INSIST(version == rbtdb->future_version); + /* + * The current version is going to be replaced. + * Release the (likely last) reference to it from the + * DB itself and unlink it from the open list. + */ + cur_version = rbtdb->current_version; + isc_refcount_decrement(&cur_version->references, + &cur_ref); + if (cur_ref == 0) { + if (cur_version->serial == rbtdb->least_serial) + INSIST(EMPTY(cur_version->changed_list)); + UNLINK(rbtdb->open_versions, + cur_version, link); + } + if (EMPTY(rbtdb->open_versions)) { + /* + * We're going to become the least open + * version. + */ + make_least_version(rbtdb, version, + &cleanup_list); + } else { + /* + * Some other open version is the + * least version. We can't cleanup + * records that were changed in this + * version because the older versions + * may still be in use by an open + * version. + * + * We can, however, discard the + * changed records for things that + * we've added that didn't exist in + * prior versions. + */ + cleanup_nondirty(version, &cleanup_list); + } + /* + * If the (soon to be former) current version + * isn't being used by anyone, we can clean + * it up. + */ + if (cur_ref == 0) { + cleanup_version = cur_version; + APPENDLIST(version->changed_list, + cleanup_version->changed_list, + link); + } + /* + * Become the current version. + */ + version->writer = ISC_FALSE; + rbtdb->current_version = version; + rbtdb->current_serial = version->serial; + rbtdb->future_version = NULL; + + /* + * Keep the current version in the open list, and + * gain a reference for the DB itself (see the DB + * creation function below). This must be the only + * case where we need to increment the counter from + * zero and need to use isc_refcount_increment0(). + */ + isc_refcount_increment0(&version->references, + &cur_ref); + INSIST(cur_ref == 1); + PREPEND(rbtdb->open_versions, + rbtdb->current_version, link); + } else { + /* + * We're rolling back this transaction. + */ + cleanup_list = version->changed_list; + ISC_LIST_INIT(version->changed_list); + rollback = ISC_TRUE; + cleanup_version = version; + rbtdb->future_version = NULL; + } + } else { + if (version != rbtdb->current_version) { + /* + * There are no external or internal references + * to this version and it can be cleaned up. + */ + cleanup_version = version; + + /* + * Find the version with the least serial + * number greater than ours. + */ + least_greater = PREV(version, link); + if (least_greater == NULL) + least_greater = rbtdb->current_version; + + INSIST(version->serial < least_greater->serial); + /* + * Is this the least open version? + */ + if (version->serial == rbtdb->least_serial) { + /* + * Yes. Install the new least open + * version. + */ + make_least_version(rbtdb, + least_greater, + &cleanup_list); + } else { + /* + * Add any unexecuted cleanups to + * those of the least greater version. + */ + APPENDLIST(least_greater->changed_list, + version->changed_list, + link); + } + } else if (version->serial == rbtdb->least_serial) + INSIST(EMPTY(version->changed_list)); + UNLINK(rbtdb->open_versions, version, link); + } + least_serial = rbtdb->least_serial; + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + + /* + * Update the zone's secure status. + */ + if (version->writer && commit && !IS_CACHE(rbtdb)) + rbtdb->secure = iszonesecure(db, rbtdb->origin_node); + + if (cleanup_version != NULL) { + INSIST(EMPTY(cleanup_version->changed_list)); + isc_mem_put(rbtdb->common.mctx, cleanup_version, + sizeof(*cleanup_version)); + } + + if (!EMPTY(cleanup_list)) { + for (changed = HEAD(cleanup_list); + changed != NULL; + changed = next_changed) { + nodelock_t *lock; + + next_changed = NEXT(changed, link); + rbtnode = changed->node; + lock = &rbtdb->node_locks[rbtnode->locknum].lock; + + NODE_LOCK(lock, isc_rwlocktype_write); + if (rollback) + rollback_node(rbtnode, serial); + decrement_reference(rbtdb, rbtnode, least_serial, + isc_rwlocktype_write, + isc_rwlocktype_none); + NODE_UNLOCK(lock, isc_rwlocktype_write); + + isc_mem_put(rbtdb->common.mctx, changed, + sizeof(*changed)); + } + } + + end: + *versionp = NULL; +} + +/* + * Add the necessary magic for the wildcard name 'name' + * to be found in 'rbtdb'. + * + * In order for wildcard matching to work correctly in + * zone_find(), we must ensure that a node for the wildcarding + * level exists in the database, and has its 'find_callback' + * and 'wild' bits set. + * + * E.g. if the wildcard name is "*.sub.example." then we + * must ensure that "sub.example." exists and is marked as + * a wildcard level. + */ +static isc_result_t +add_wildcard_magic(dns_rbtdb_t *rbtdb, dns_name_t *name) { + isc_result_t result; + dns_name_t foundname; + dns_offsets_t offsets; + unsigned int n; + dns_rbtnode_t *node = NULL; + + dns_name_init(&foundname, offsets); + n = dns_name_countlabels(name); + INSIST(n >= 2); + n--; + dns_name_getlabelsequence(name, 1, n, &foundname); + result = dns_rbt_addnode(rbtdb->tree, &foundname, &node); + if (result != ISC_R_SUCCESS && result != ISC_R_EXISTS) + return (result); + node->find_callback = 1; + node->wild = 1; + return (ISC_R_SUCCESS); +} + +static isc_result_t +add_empty_wildcards(dns_rbtdb_t *rbtdb, dns_name_t *name) { + isc_result_t result; + dns_name_t foundname; + dns_offsets_t offsets; + unsigned int n, l, i; + + dns_name_init(&foundname, offsets); + n = dns_name_countlabels(name); + l = dns_name_countlabels(&rbtdb->common.origin); + i = l + 1; + while (i < n) { + dns_rbtnode_t *node = NULL; /* dummy */ + dns_name_getlabelsequence(name, n - i, i, &foundname); + if (dns_name_iswildcard(&foundname)) { + result = add_wildcard_magic(rbtdb, &foundname); + if (result != ISC_R_SUCCESS) + return (result); + result = dns_rbt_addnode(rbtdb->tree, &foundname, + &node); + if (result != ISC_R_SUCCESS && result != ISC_R_EXISTS) + return (result); + } + i++; + } + return (ISC_R_SUCCESS); +} + +static isc_result_t +findnode(dns_db_t *db, dns_name_t *name, isc_boolean_t create, + dns_dbnode_t **nodep) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *node = NULL; + dns_name_t nodename; + isc_result_t result; + isc_rwlocktype_t locktype = isc_rwlocktype_read; + + REQUIRE(VALID_RBTDB(rbtdb)); + + dns_name_init(&nodename, NULL); + RWLOCK(&rbtdb->tree_lock, locktype); + result = dns_rbt_findnode(rbtdb->tree, name, NULL, &node, NULL, + DNS_RBTFIND_EMPTYDATA, NULL, NULL); + if (result != ISC_R_SUCCESS) { + RWUNLOCK(&rbtdb->tree_lock, locktype); + if (!create) { + if (result == DNS_R_PARTIALMATCH) + result = ISC_R_NOTFOUND; + return (result); + } + /* + * It would be nice to try to upgrade the lock instead of + * unlocking then relocking. + */ + locktype = isc_rwlocktype_write; + RWLOCK(&rbtdb->tree_lock, locktype); + node = NULL; + result = dns_rbt_addnode(rbtdb->tree, name, &node); + if (result == ISC_R_SUCCESS) { + dns_rbt_namefromnode(node, &nodename); +#ifdef DNS_RBT_USEHASH + node->locknum = node->hashval % rbtdb->node_lock_count; +#else + node->locknum = dns_name_hash(&nodename, ISC_TRUE) % + rbtdb->node_lock_count; +#endif + add_empty_wildcards(rbtdb, name); + + if (dns_name_iswildcard(name)) { + result = add_wildcard_magic(rbtdb, name); + if (result != ISC_R_SUCCESS) { + RWUNLOCK(&rbtdb->tree_lock, locktype); + return (result); + } + } + } else if (result != ISC_R_EXISTS) { + RWUNLOCK(&rbtdb->tree_lock, locktype); + return (result); + } + } + NODE_STRONGLOCK(&rbtdb->node_locks[node->locknum].lock); + new_reference(rbtdb, node); + NODE_STRONGUNLOCK(&rbtdb->node_locks[node->locknum].lock); + RWUNLOCK(&rbtdb->tree_lock, locktype); + + *nodep = (dns_dbnode_t *)node; + + return (ISC_R_SUCCESS); +} + +static isc_result_t +zone_zonecut_callback(dns_rbtnode_t *node, dns_name_t *name, void *arg) { + rbtdb_search_t *search = arg; + rdatasetheader_t *header, *header_next; + rdatasetheader_t *dname_header, *sigdname_header, *ns_header; + rdatasetheader_t *found; + isc_result_t result; + dns_rbtnode_t *onode; + + /* + * We only want to remember the topmost zone cut, since it's the one + * that counts, so we'll just continue if we've already found a + * zonecut. + */ + if (search->zonecut != NULL) + return (DNS_R_CONTINUE); + + found = NULL; + result = DNS_R_CONTINUE; + onode = search->rbtdb->origin_node; + + NODE_LOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + /* + * Look for an NS or DNAME rdataset active in our version. + */ + ns_header = NULL; + dname_header = NULL; + sigdname_header = NULL; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->type == dns_rdatatype_ns || + header->type == dns_rdatatype_dname || + header->type == RBTDB_RDATATYPE_SIGDNAME) { + do { + if (header->serial <= search->serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) { + if (header->type == dns_rdatatype_dname) + dname_header = header; + else if (header->type == + RBTDB_RDATATYPE_SIGDNAME) + sigdname_header = header; + else if (node != onode || + IS_STUB(search->rbtdb)) { + /* + * We've found an NS rdataset that + * isn't at the origin node. We check + * that they're not at the origin node, + * because otherwise we'd erroneously + * treat the zone top as if it were + * a delegation. + */ + ns_header = header; + } + } + } + } + + /* + * Did we find anything? + */ + if (dname_header != NULL) { + /* + * Note that DNAME has precedence over NS if both exist. + */ + found = dname_header; + search->zonecut_sigrdataset = sigdname_header; + } else if (ns_header != NULL) { + found = ns_header; + search->zonecut_sigrdataset = NULL; + } + + if (found != NULL) { + /* + * We increment the reference count on node to ensure that + * search->zonecut_rdataset will still be valid later. + */ + new_reference(search->rbtdb, node); + search->zonecut = node; + search->zonecut_rdataset = found; + search->need_cleanup = ISC_TRUE; + /* + * Since we've found a zonecut, anything beneath it is + * glue and is not subject to wildcard matching, so we + * may clear search->wild. + */ + search->wild = ISC_FALSE; + if ((search->options & DNS_DBFIND_GLUEOK) == 0) { + /* + * If the caller does not want to find glue, then + * this is the best answer and the search should + * stop now. + */ + result = DNS_R_PARTIALMATCH; + } else { + dns_name_t *zcname; + + /* + * The search will continue beneath the zone cut. + * This may or may not be the best match. In case it + * is, we need to remember the node name. + */ + zcname = dns_fixedname_name(&search->zonecut_name); + RUNTIME_CHECK(dns_name_copy(name, zcname, NULL) == + ISC_R_SUCCESS); + search->copy_name = ISC_TRUE; + } + } else { + /* + * There is no zonecut at this node which is active in this + * version. + * + * If this is a "wild" node and the caller hasn't disabled + * wildcard matching, remember that we've seen a wild node + * in case we need to go searching for wildcard matches + * later on. + */ + if (node->wild && (search->options & DNS_DBFIND_NOWILD) == 0) + search->wild = ISC_TRUE; + } + + NODE_UNLOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + return (result); +} + +static inline void +bind_rdataset(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, + rdatasetheader_t *header, isc_stdtime_t now, + dns_rdataset_t *rdataset) +{ + unsigned char *raw; /* RDATASLAB */ + + /* + * Caller must be holding the node reader lock. + * XXXJT: technically, we need a writer lock, since we'll increment + * the header count below. However, since the actual counter value + * doesn't matter, we prioritize performance here. (We may want to + * use atomic increment when available). + */ + + if (rdataset == NULL) + return; + + new_reference(rbtdb, node); + + INSIST(rdataset->methods == NULL); /* We must be disassociated. */ + + rdataset->methods = &rdataset_methods; + rdataset->rdclass = rbtdb->common.rdclass; + rdataset->type = RBTDB_RDATATYPE_BASE(header->type); + rdataset->covers = RBTDB_RDATATYPE_EXT(header->type); + rdataset->ttl = header->ttl - now; + rdataset->trust = header->trust; + if (NXDOMAIN(header)) + rdataset->attributes |= DNS_RDATASETATTR_NXDOMAIN; + rdataset->private1 = rbtdb; + rdataset->private2 = node; + raw = (unsigned char *)header + sizeof(*header); + rdataset->private3 = raw; + rdataset->count = header->count++; + if (rdataset->count == ISC_UINT32_MAX) + rdataset->count = 0; + + /* + * Reset iterator state. + */ + rdataset->privateuint4 = 0; + rdataset->private5 = NULL; + + /* + * Add noqname proof. + */ + rdataset->private6 = header->noqname; + if (rdataset->private6 != NULL) + rdataset->attributes |= DNS_RDATASETATTR_NOQNAME; +} + +static inline isc_result_t +setup_delegation(rbtdb_search_t *search, dns_dbnode_t **nodep, + dns_name_t *foundname, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) +{ + isc_result_t result; + dns_name_t *zcname; + rbtdb_rdatatype_t type; + dns_rbtnode_t *node; + + /* + * The caller MUST NOT be holding any node locks. + */ + + node = search->zonecut; + type = search->zonecut_rdataset->type; + + /* + * If we have to set foundname, we do it before anything else. + * If we were to set foundname after we had set nodep or bound the + * rdataset, then we'd have to undo that work if dns_name_copy() + * failed. By setting foundname first, there's nothing to undo if + * we have trouble. + */ + if (foundname != NULL && search->copy_name) { + zcname = dns_fixedname_name(&search->zonecut_name); + result = dns_name_copy(zcname, foundname, NULL); + if (result != ISC_R_SUCCESS) + return (result); + } + if (nodep != NULL) { + /* + * Note that we don't have to increment the node's reference + * count here because we're going to use the reference we + * already have in the search block. + */ + *nodep = node; + search->need_cleanup = ISC_FALSE; + } + if (rdataset != NULL) { + NODE_LOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + bind_rdataset(search->rbtdb, node, search->zonecut_rdataset, + search->now, rdataset); + if (sigrdataset != NULL && search->zonecut_sigrdataset != NULL) + bind_rdataset(search->rbtdb, node, + search->zonecut_sigrdataset, + search->now, sigrdataset); + NODE_UNLOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + } + + if (type == dns_rdatatype_dname) + return (DNS_R_DNAME); + return (DNS_R_DELEGATION); +} + +static inline isc_boolean_t +valid_glue(rbtdb_search_t *search, dns_name_t *name, rbtdb_rdatatype_t type, + dns_rbtnode_t *node) +{ + unsigned char *raw; /* RDATASLAB */ + unsigned int count, size; + dns_name_t ns_name; + isc_boolean_t valid = ISC_FALSE; + dns_offsets_t offsets; + isc_region_t region; + rdatasetheader_t *header; + + /* + * No additional locking is required. + */ + + /* + * Valid glue types are A, AAAA, A6. NS is also a valid glue type + * if it occurs at a zone cut, but is not valid below it. + */ + if (type == dns_rdatatype_ns) { + if (node != search->zonecut) { + return (ISC_FALSE); + } + } else if (type != dns_rdatatype_a && + type != dns_rdatatype_aaaa && + type != dns_rdatatype_a6) { + return (ISC_FALSE); + } + + header = search->zonecut_rdataset; + raw = (unsigned char *)header + sizeof(*header); + count = raw[0] * 256 + raw[1]; +#if DNS_RDATASET_FIXED + raw += 2 + (4 * count); +#else + raw += 2; +#endif + + while (count > 0) { + count--; + size = raw[0] * 256 + raw[1]; +#if DNS_RDATASET_FIXED + raw += 4; +#else + raw += 2; +#endif + region.base = raw; + region.length = size; + raw += size; + /* + * XXX Until we have rdata structures, we have no choice but + * to directly access the rdata format. + */ + dns_name_init(&ns_name, offsets); + dns_name_fromregion(&ns_name, ®ion); + if (dns_name_compare(&ns_name, name) == 0) { + valid = ISC_TRUE; + break; + } + } + + return (valid); +} + +static inline isc_boolean_t +activeempty(rbtdb_search_t *search, dns_rbtnodechain_t *chain, + dns_name_t *name) +{ + dns_fixedname_t fnext; + dns_fixedname_t forigin; + dns_name_t *next; + dns_name_t *origin; + dns_name_t prefix; + dns_rbtdb_t *rbtdb; + dns_rbtnode_t *node; + isc_result_t result; + isc_boolean_t answer = ISC_FALSE; + rdatasetheader_t *header; + + rbtdb = search->rbtdb; + + dns_name_init(&prefix, NULL); + dns_fixedname_init(&fnext); + next = dns_fixedname_name(&fnext); + dns_fixedname_init(&forigin); + origin = dns_fixedname_name(&forigin); + + result = dns_rbtnodechain_next(chain, NULL, NULL); + while (result == ISC_R_SUCCESS || result == DNS_R_NEWORIGIN) { + node = NULL; + result = dns_rbtnodechain_current(chain, &prefix, + origin, &node); + if (result != ISC_R_SUCCESS) + break; + NODE_LOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + for (header = node->data; + header != NULL; + header = header->next) { + if (header->serial <= search->serial && + !IGNORE(header) && EXISTS(header)) + break; + } + NODE_UNLOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + if (header != NULL) + break; + result = dns_rbtnodechain_next(chain, NULL, NULL); + } + if (result == ISC_R_SUCCESS) + result = dns_name_concatenate(&prefix, origin, next, NULL); + if (result == ISC_R_SUCCESS && dns_name_issubdomain(next, name)) + answer = ISC_TRUE; + return (answer); +} + +static inline isc_boolean_t +activeemtpynode(rbtdb_search_t *search, dns_name_t *qname, dns_name_t *wname) { + dns_fixedname_t fnext; + dns_fixedname_t forigin; + dns_fixedname_t fprev; + dns_name_t *next; + dns_name_t *origin; + dns_name_t *prev; + dns_name_t name; + dns_name_t rname; + dns_name_t tname; + dns_rbtdb_t *rbtdb; + dns_rbtnode_t *node; + dns_rbtnodechain_t chain; + isc_boolean_t check_next = ISC_TRUE; + isc_boolean_t check_prev = ISC_TRUE; + isc_boolean_t answer = ISC_FALSE; + isc_result_t result; + rdatasetheader_t *header; + unsigned int n; + + rbtdb = search->rbtdb; + + dns_name_init(&name, NULL); + dns_name_init(&tname, NULL); + dns_name_init(&rname, NULL); + dns_fixedname_init(&fnext); + next = dns_fixedname_name(&fnext); + dns_fixedname_init(&fprev); + prev = dns_fixedname_name(&fprev); + dns_fixedname_init(&forigin); + origin = dns_fixedname_name(&forigin); + + /* + * Find if qname is at or below a empty node. + * Use our own copy of the chain. + */ + + chain = search->chain; + do { + node = NULL; + result = dns_rbtnodechain_current(&chain, &name, + origin, &node); + if (result != ISC_R_SUCCESS) + break; + NODE_LOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + for (header = node->data; + header != NULL; + header = header->next) { + if (header->serial <= search->serial && + !IGNORE(header) && EXISTS(header)) + break; + } + NODE_UNLOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + if (header != NULL) + break; + result = dns_rbtnodechain_prev(&chain, NULL, NULL); + } while (result == ISC_R_SUCCESS || result == DNS_R_NEWORIGIN); + if (result == ISC_R_SUCCESS) + result = dns_name_concatenate(&name, origin, prev, NULL); + if (result != ISC_R_SUCCESS) + check_prev = ISC_FALSE; + + result = dns_rbtnodechain_next(&chain, NULL, NULL); + while (result == ISC_R_SUCCESS || result == DNS_R_NEWORIGIN) { + node = NULL; + result = dns_rbtnodechain_current(&chain, &name, + origin, &node); + if (result != ISC_R_SUCCESS) + break; + NODE_LOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + for (header = node->data; + header != NULL; + header = header->next) { + if (header->serial <= search->serial && + !IGNORE(header) && EXISTS(header)) + break; + } + NODE_UNLOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + if (header != NULL) + break; + result = dns_rbtnodechain_next(&chain, NULL, NULL); + } + if (result == ISC_R_SUCCESS) + result = dns_name_concatenate(&name, origin, next, NULL); + if (result != ISC_R_SUCCESS) + check_next = ISC_FALSE; + + dns_name_clone(qname, &rname); + + /* + * Remove the wildcard label to find the terminal name. + */ + n = dns_name_countlabels(wname); + dns_name_getlabelsequence(wname, 1, n - 1, &tname); + + do { + if ((check_prev && dns_name_issubdomain(prev, &rname)) || + (check_next && dns_name_issubdomain(next, &rname))) { + answer = ISC_TRUE; + break; + } + /* + * Remove the left hand label. + */ + n = dns_name_countlabels(&rname); + dns_name_getlabelsequence(&rname, 1, n - 1, &rname); + } while (!dns_name_equal(&rname, &tname)); + return (answer); +} + +static inline isc_result_t +find_wildcard(rbtdb_search_t *search, dns_rbtnode_t **nodep, + dns_name_t *qname) +{ + unsigned int i, j; + dns_rbtnode_t *node, *level_node, *wnode; + rdatasetheader_t *header; + isc_result_t result = ISC_R_NOTFOUND; + dns_name_t name; + dns_name_t *wname; + dns_fixedname_t fwname; + dns_rbtdb_t *rbtdb; + isc_boolean_t done, wild, active; + dns_rbtnodechain_t wchain; + + /* + * Caller must be holding the tree lock and MUST NOT be holding + * any node locks. + */ + + /* + * Examine each ancestor level. If the level's wild bit + * is set, then construct the corresponding wildcard name and + * search for it. If the wildcard node exists, and is active in + * this version, we're done. If not, then we next check to see + * if the ancestor is active in this version. If so, then there + * can be no possible wildcard match and again we're done. If not, + * continue the search. + */ + + rbtdb = search->rbtdb; + i = search->chain.level_matches; + done = ISC_FALSE; + node = *nodep; + do { + NODE_LOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + /* + * First we try to figure out if this node is active in + * the search's version. We do this now, even though we + * may not need the information, because it simplifies the + * locking and code flow. + */ + for (header = node->data; + header != NULL; + header = header->next) { + if (header->serial <= search->serial && + !IGNORE(header) && EXISTS(header)) + break; + } + if (header != NULL) + active = ISC_TRUE; + else + active = ISC_FALSE; + + if (node->wild) + wild = ISC_TRUE; + else + wild = ISC_FALSE; + + NODE_UNLOCK(&(rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + if (wild) { + /* + * Construct the wildcard name for this level. + */ + dns_name_init(&name, NULL); + dns_rbt_namefromnode(node, &name); + dns_fixedname_init(&fwname); + wname = dns_fixedname_name(&fwname); + result = dns_name_concatenate(dns_wildcardname, &name, + wname, NULL); + j = i; + while (result == ISC_R_SUCCESS && j != 0) { + j--; + level_node = search->chain.levels[j]; + dns_name_init(&name, NULL); + dns_rbt_namefromnode(level_node, &name); + result = dns_name_concatenate(wname, + &name, + wname, + NULL); + } + if (result != ISC_R_SUCCESS) + break; + + wnode = NULL; + dns_rbtnodechain_init(&wchain, NULL); + result = dns_rbt_findnode(rbtdb->tree, wname, + NULL, &wnode, &wchain, + DNS_RBTFIND_EMPTYDATA, + NULL, NULL); + if (result == ISC_R_SUCCESS) { + nodelock_t *lock; + + /* + * We have found the wildcard node. If it + * is active in the search's version, we're + * done. + */ + lock = &rbtdb->node_locks[wnode->locknum].lock; + NODE_LOCK(lock, isc_rwlocktype_read); + for (header = wnode->data; + header != NULL; + header = header->next) { + if (header->serial <= search->serial && + !IGNORE(header) && EXISTS(header)) + break; + } + NODE_UNLOCK(lock, isc_rwlocktype_read); + if (header != NULL || + activeempty(search, &wchain, wname)) { + if (activeemtpynode(search, qname, + wname)) { + return (ISC_R_NOTFOUND); + } + /* + * The wildcard node is active! + * + * Note: result is still ISC_R_SUCCESS + * so we don't have to set it. + */ + *nodep = wnode; + break; + } + } else if (result != ISC_R_NOTFOUND && + result != DNS_R_PARTIALMATCH) { + /* + * An error has occurred. Bail out. + */ + break; + } + } + + if (active) { + /* + * The level node is active. Any wildcarding + * present at higher levels has no + * effect and we're done. + */ + result = ISC_R_NOTFOUND; + break; + } + + if (i > 0) { + i--; + node = search->chain.levels[i]; + } else + done = ISC_TRUE; + } while (!done); + + return (result); +} + +static inline isc_result_t +find_closest_nsec(rbtdb_search_t *search, dns_dbnode_t **nodep, + dns_name_t *foundname, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset, isc_boolean_t need_sig) +{ + dns_rbtnode_t *node; + rdatasetheader_t *header, *header_next, *found, *foundsig; + isc_boolean_t empty_node; + isc_result_t result; + dns_fixedname_t fname, forigin; + dns_name_t *name, *origin; + + do { + node = NULL; + dns_fixedname_init(&fname); + name = dns_fixedname_name(&fname); + dns_fixedname_init(&forigin); + origin = dns_fixedname_name(&forigin); + result = dns_rbtnodechain_current(&search->chain, name, + origin, &node); + if (result != ISC_R_SUCCESS) + return (result); + NODE_LOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + found = NULL; + foundsig = NULL; + empty_node = ISC_TRUE; + for (header = node->data; + header != NULL; + header = header_next) { + header_next = header->next; + /* + * Look for an active, extant NSEC or RRSIG NSEC. + */ + do { + if (header->serial <= search->serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) { + /* + * We now know that there is at least one + * active rdataset at this node. + */ + empty_node = ISC_FALSE; + if (header->type == dns_rdatatype_nsec) { + found = header; + if (foundsig != NULL) + break; + } else if (header->type == + RBTDB_RDATATYPE_SIGNSEC) { + foundsig = header; + if (found != NULL) + break; + } + } + } + if (!empty_node) { + if (found != NULL && + (foundsig != NULL || !need_sig)) + { + /* + * We've found the right NSEC record. + * + * Note: for this to really be the right + * NSEC record, it's essential that the NSEC + * records of any nodes obscured by a zone + * cut have been removed; we assume this is + * the case. + */ + result = dns_name_concatenate(name, origin, + foundname, NULL); + if (result == ISC_R_SUCCESS) { + if (nodep != NULL) { + new_reference(search->rbtdb, + node); + *nodep = node; + } + bind_rdataset(search->rbtdb, node, + found, search->now, + rdataset); + if (foundsig != NULL) + bind_rdataset(search->rbtdb, + node, + foundsig, + search->now, + sigrdataset); + } + } else if (found == NULL && foundsig == NULL) { + /* + * This node is active, but has no NSEC or + * RRSIG NSEC. That means it's glue or + * other obscured zone data that isn't + * relevant for our search. Treat the + * node as if it were empty and keep looking. + */ + empty_node = ISC_TRUE; + result = dns_rbtnodechain_prev(&search->chain, + NULL, NULL); + } else { + /* + * We found an active node, but either the + * NSEC or the RRSIG NSEC is missing. This + * shouldn't happen. + */ + result = DNS_R_BADDB; + } + } else { + /* + * This node isn't active. We've got to keep + * looking. + */ + result = dns_rbtnodechain_prev(&search->chain, NULL, + NULL); + } + NODE_UNLOCK(&(search->rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + } while (empty_node && result == ISC_R_SUCCESS); + + /* + * If the result is ISC_R_NOMORE, then we got to the beginning of + * the database and didn't find a NSEC record. This shouldn't + * happen. + */ + if (result == ISC_R_NOMORE) + result = DNS_R_BADDB; + + return (result); +} + +static isc_result_t +zone_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version, + dns_rdatatype_t type, unsigned int options, isc_stdtime_t now, + dns_dbnode_t **nodep, dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + dns_rbtnode_t *node = NULL; + isc_result_t result; + rbtdb_search_t search; + isc_boolean_t cname_ok = ISC_TRUE; + isc_boolean_t close_version = ISC_FALSE; + isc_boolean_t maybe_zonecut = ISC_FALSE; + isc_boolean_t at_zonecut = ISC_FALSE; + isc_boolean_t wild; + isc_boolean_t empty_node; + rdatasetheader_t *header, *header_next, *found, *nsecheader; + rdatasetheader_t *foundsig, *cnamesig, *nsecsig; + rbtdb_rdatatype_t sigtype; + isc_boolean_t active; + dns_rbtnodechain_t chain; + nodelock_t *lock; + + + search.rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(search.rbtdb)); + + /* + * We don't care about 'now'. + */ + UNUSED(now); + + /* + * If the caller didn't supply a version, attach to the current + * version. + */ + if (version == NULL) { + currentversion(db, &version); + close_version = ISC_TRUE; + } + + search.rbtversion = version; + search.serial = search.rbtversion->serial; + search.options = options; + search.copy_name = ISC_FALSE; + search.need_cleanup = ISC_FALSE; + search.wild = ISC_FALSE; + search.zonecut = NULL; + dns_fixedname_init(&search.zonecut_name); + dns_rbtnodechain_init(&search.chain, search.rbtdb->common.mctx); + search.now = 0; + + /* + * 'wild' will be true iff. we've matched a wildcard. + */ + wild = ISC_FALSE; + + RWLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + /* + * Search down from the root of the tree. If, while going down, we + * encounter a callback node, zone_zonecut_callback() will search the + * rdatasets at the zone cut for active DNAME or NS rdatasets. + */ + result = dns_rbt_findnode(search.rbtdb->tree, name, foundname, &node, + &search.chain, DNS_RBTFIND_EMPTYDATA, + zone_zonecut_callback, &search); + + if (result == DNS_R_PARTIALMATCH) { + partial_match: + if (search.zonecut != NULL) { + result = setup_delegation(&search, nodep, foundname, + rdataset, sigrdataset); + goto tree_exit; + } + + if (search.wild) { + /* + * At least one of the levels in the search chain + * potentially has a wildcard. For each such level, + * we must see if there's a matching wildcard active + * in the current version. + */ + result = find_wildcard(&search, &node, name); + if (result == ISC_R_SUCCESS) { + result = dns_name_copy(name, foundname, NULL); + if (result != ISC_R_SUCCESS) + goto tree_exit; + wild = ISC_TRUE; + goto found; + } + else if (result != ISC_R_NOTFOUND) + goto tree_exit; + } + + chain = search.chain; + active = activeempty(&search, &chain, name); + + /* + * If we're here, then the name does not exist, is not + * beneath a zonecut, and there's no matching wildcard. + */ + if (search.rbtdb->secure || + (search.options & DNS_DBFIND_FORCENSEC) != 0) + { + result = find_closest_nsec(&search, nodep, foundname, + rdataset, sigrdataset, + search.rbtdb->secure); + if (result == ISC_R_SUCCESS) + result = active ? DNS_R_EMPTYNAME : + DNS_R_NXDOMAIN; + } else + result = active ? DNS_R_EMPTYNAME : DNS_R_NXDOMAIN; + goto tree_exit; + } else if (result != ISC_R_SUCCESS) + goto tree_exit; + + found: + /* + * We have found a node whose name is the desired name, or we + * have matched a wildcard. + */ + + if (search.zonecut != NULL) { + /* + * If we're beneath a zone cut, we don't want to look for + * CNAMEs because they're not legitimate zone glue. + */ + cname_ok = ISC_FALSE; + } else { + /* + * The node may be a zone cut itself. If it might be one, + * make sure we check for it later. + */ + if (node->find_callback && + (node != search.rbtdb->origin_node || + IS_STUB(search.rbtdb)) && + !dns_rdatatype_atparent(type)) + maybe_zonecut = ISC_TRUE; + } + + /* + * Certain DNSSEC types are not subject to CNAME matching + * (RFC4035, section 2.5 and RFC3007). + * + * We don't check for RRSIG, because we don't store RRSIG records + * directly. + */ + if (type == dns_rdatatype_key || type == dns_rdatatype_nsec) + cname_ok = ISC_FALSE; + + /* + * We now go looking for rdata... + */ + + NODE_LOCK(&(search.rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + found = NULL; + foundsig = NULL; + sigtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, type); + nsecheader = NULL; + nsecsig = NULL; + cnamesig = NULL; + empty_node = ISC_TRUE; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + /* + * Look for an active, extant rdataset. + */ + do { + if (header->serial <= search.serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) { + /* + * We now know that there is at least one active + * rdataset at this node. + */ + empty_node = ISC_FALSE; + + /* + * Do special zone cut handling, if requested. + */ + if (maybe_zonecut && + header->type == dns_rdatatype_ns) { + /* + * We increment the reference count on node to + * ensure that search->zonecut_rdataset will + * still be valid later. + */ + new_reference(search.rbtdb, node); + search.zonecut = node; + search.zonecut_rdataset = header; + search.zonecut_sigrdataset = NULL; + search.need_cleanup = ISC_TRUE; + maybe_zonecut = ISC_FALSE; + at_zonecut = ISC_TRUE; + /* + * It is not clear if KEY should still be + * allowed at the parent side of the zone + * cut or not. It is needed for RFC3007 + * validated updates. + */ + if ((search.options & DNS_DBFIND_GLUEOK) == 0 + && type != dns_rdatatype_nsec + && type != dns_rdatatype_key) { + /* + * Glue is not OK, but any answer we + * could return would be glue. Return + * the delegation. + */ + found = NULL; + break; + } + if (found != NULL && foundsig != NULL) + break; + } + + /* + * If we found a type we were looking for, + * remember it. + */ + if (header->type == type || + type == dns_rdatatype_any || + (header->type == dns_rdatatype_cname && + cname_ok)) { + /* + * We've found the answer! + */ + found = header; + if (header->type == dns_rdatatype_cname && + cname_ok) { + /* + * We may be finding a CNAME instead + * of the desired type. + * + * If we've already got the CNAME RRSIG, + * use it, otherwise change sigtype + * so that we find it. + */ + if (cnamesig != NULL) + foundsig = cnamesig; + else + sigtype = + RBTDB_RDATATYPE_SIGCNAME; + } + /* + * If we've got all we need, end the search. + */ + if (!maybe_zonecut && foundsig != NULL) + break; + } else if (header->type == sigtype) { + /* + * We've found the RRSIG rdataset for our + * target type. Remember it. + */ + foundsig = header; + /* + * If we've got all we need, end the search. + */ + if (!maybe_zonecut && found != NULL) + break; + } else if (header->type == dns_rdatatype_nsec) { + /* + * Remember a NSEC rdataset even if we're + * not specifically looking for it, because + * we might need it later. + */ + nsecheader = header; + } else if (header->type == RBTDB_RDATATYPE_SIGNSEC) { + /* + * If we need the NSEC rdataset, we'll also + * need its signature. + */ + nsecsig = header; + } else if (cname_ok && + header->type == RBTDB_RDATATYPE_SIGCNAME) { + /* + * If we get a CNAME match, we'll also need + * its signature. + */ + cnamesig = header; + } + } + } + + if (empty_node) { + /* + * We have an exact match for the name, but there are no + * active rdatasets in the desired version. That means that + * this node doesn't exist in the desired version, and that + * we really have a partial match. + */ + if (!wild) { + lock = &search.rbtdb->node_locks[node->locknum].lock; + NODE_UNLOCK(lock, isc_rwlocktype_read); + goto partial_match; + } + } + + /* + * If we didn't find what we were looking for... + */ + if (found == NULL) { + if (search.zonecut != NULL) { + /* + * We were trying to find glue at a node beneath a + * zone cut, but didn't. + * + * Return the delegation. + */ + lock = &search.rbtdb->node_locks[node->locknum].lock; + NODE_UNLOCK(lock, isc_rwlocktype_read); + result = setup_delegation(&search, nodep, foundname, + rdataset, sigrdataset); + goto tree_exit; + } + /* + * The desired type doesn't exist. + */ + result = DNS_R_NXRRSET; + if (search.rbtdb->secure && + (nsecheader == NULL || nsecsig == NULL)) { + /* + * The zone is secure but there's no NSEC, + * or the NSEC has no signature! + */ + if (!wild) { + result = DNS_R_BADDB; + goto node_exit; + } + + lock = &search.rbtdb->node_locks[node->locknum].lock; + NODE_UNLOCK(lock, isc_rwlocktype_read); + result = find_closest_nsec(&search, nodep, foundname, + rdataset, sigrdataset, + search.rbtdb->secure); + if (result == ISC_R_SUCCESS) + result = DNS_R_EMPTYWILD; + goto tree_exit; + } + if ((search.options & DNS_DBFIND_FORCENSEC) != 0 && + nsecheader == NULL) + { + /* + * There's no NSEC record, and we were told + * to find one. + */ + result = DNS_R_BADDB; + goto node_exit; + } + if (nodep != NULL) { + new_reference(search.rbtdb, node); + *nodep = node; + } + if (search.rbtdb->secure || + (search.options & DNS_DBFIND_FORCENSEC) != 0) + { + bind_rdataset(search.rbtdb, node, nsecheader, + 0, rdataset); + if (nsecsig != NULL) + bind_rdataset(search.rbtdb, node, + nsecsig, 0, sigrdataset); + } + if (wild) + foundname->attributes |= DNS_NAMEATTR_WILDCARD; + goto node_exit; + } + + /* + * We found what we were looking for, or we found a CNAME. + */ + + if (type != found->type && + type != dns_rdatatype_any && + found->type == dns_rdatatype_cname) { + /* + * We weren't doing an ANY query and we found a CNAME instead + * of the type we were looking for, so we need to indicate + * that result to the caller. + */ + result = DNS_R_CNAME; + } else if (search.zonecut != NULL) { + /* + * If we're beneath a zone cut, we must indicate that the + * result is glue, unless we're actually at the zone cut + * and the type is NSEC or KEY. + */ + if (search.zonecut == node) { + /* + * It is not clear if KEY should still be + * allowed at the parent side of the zone + * cut or not. It is needed for RFC3007 + * validated updates. + */ + if (type == dns_rdatatype_nsec || + type == dns_rdatatype_key) + result = ISC_R_SUCCESS; + else if (type == dns_rdatatype_any) + result = DNS_R_ZONECUT; + else + result = DNS_R_GLUE; + } else + result = DNS_R_GLUE; + /* + * We might have found data that isn't glue, but was occluded + * by a dynamic update. If the caller cares about this, they + * will have told us to validate glue. + * + * XXX We should cache the glue validity state! + */ + if (result == DNS_R_GLUE && + (search.options & DNS_DBFIND_VALIDATEGLUE) != 0 && + !valid_glue(&search, foundname, type, node)) { + lock = &search.rbtdb->node_locks[node->locknum].lock; + NODE_UNLOCK(lock, isc_rwlocktype_read); + result = setup_delegation(&search, nodep, foundname, + rdataset, sigrdataset); + goto tree_exit; + } + } else { + /* + * An ordinary successful query! + */ + result = ISC_R_SUCCESS; + } + + if (nodep != NULL) { + if (!at_zonecut) + new_reference(search.rbtdb, node); + else + search.need_cleanup = ISC_FALSE; + *nodep = node; + } + + if (type != dns_rdatatype_any) { + bind_rdataset(search.rbtdb, node, found, 0, rdataset); + if (foundsig != NULL) + bind_rdataset(search.rbtdb, node, foundsig, 0, + sigrdataset); + } + + if (wild) + foundname->attributes |= DNS_NAMEATTR_WILDCARD; + + node_exit: + NODE_UNLOCK(&(search.rbtdb->node_locks[node->locknum].lock), + isc_rwlocktype_read); + + tree_exit: + RWUNLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + /* + * If we found a zonecut but aren't going to use it, we have to + * let go of it. + */ + if (search.need_cleanup) { + node = search.zonecut; + lock = &(search.rbtdb->node_locks[node->locknum].lock); + + NODE_LOCK(lock, isc_rwlocktype_read); + decrement_reference(search.rbtdb, node, 0, + isc_rwlocktype_read, isc_rwlocktype_none); + NODE_UNLOCK(lock, isc_rwlocktype_read); + } + + if (close_version) + closeversion(db, &version, ISC_FALSE); + + dns_rbtnodechain_reset(&search.chain); + + return (result); +} + +static isc_result_t +zone_findzonecut(dns_db_t *db, dns_name_t *name, unsigned int options, + isc_stdtime_t now, dns_dbnode_t **nodep, + dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + UNUSED(db); + UNUSED(name); + UNUSED(options); + UNUSED(now); + UNUSED(nodep); + UNUSED(foundname); + UNUSED(rdataset); + UNUSED(sigrdataset); + + FATAL_ERROR(__FILE__, __LINE__, "zone_findzonecut() called!"); + + return (ISC_R_NOTIMPLEMENTED); +} + +static isc_result_t +cache_zonecut_callback(dns_rbtnode_t *node, dns_name_t *name, void *arg) { + rbtdb_search_t *search = arg; + rdatasetheader_t *header, *header_prev, *header_next; + rdatasetheader_t *dname_header, *sigdname_header; + isc_result_t result; + nodelock_t *lock; + isc_rwlocktype_t locktype; + + /* XXX comment */ + + REQUIRE(search->zonecut == NULL); + + /* + * Keep compiler silent. + */ + UNUSED(name); + + lock = &(search->rbtdb->node_locks[node->locknum].lock); + locktype = isc_rwlocktype_read; + NODE_LOCK(lock, locktype); + + /* + * Look for a DNAME or RRSIG DNAME rdataset. + */ + dname_header = NULL; + sigdname_header = NULL; + header_prev = NULL; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->ttl <= search->now) { + /* + * This rdataset is stale. If no one else is + * using the node, we can clean it up right + * now, otherwise we mark it as stale, and + * the node as dirty, so it will get cleaned + * up later. + */ + if ((header->ttl <= search->now - RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only when we + * can get write access; otherwise, we leave + * others to this work. Periodical cleaning + * will eventually take the job as the last + * resort. + * We won't downgrade the lock, since other + * rdatasets are probably stale, too. + */ + locktype = isc_rwlocktype_write; + + if (dns_rbtnode_refcurrent(node) == 0) { + isc_mem_t *mctx; + + /* + * header->down can be non-NULL if the + * refcount has just decremented to 0 + * but decrement_reference() has not + * performed clean_cache_node(), in + * which case we need to purge the + * stale headers first. + */ + mctx = search->rbtdb->common.mctx; + clean_stale_headers(mctx, header); + if (header_prev != NULL) + header_prev->next = + header->next; + else + node->data = header->next; + free_rdataset(mctx, header); + } else { + header->attributes |= + RDATASET_ATTR_STALE; + node->dirty = 1; + header_prev = header; + } + } else + header_prev = header; + } else if (header->type == dns_rdatatype_dname && + EXISTS(header)) { + dname_header = header; + header_prev = header; + } else if (header->type == RBTDB_RDATATYPE_SIGDNAME && + EXISTS(header)) { + sigdname_header = header; + header_prev = header; + } else + header_prev = header; + } + + if (dname_header != NULL && + (dname_header->trust != dns_trust_pending || + (search->options & DNS_DBFIND_PENDINGOK) != 0)) { + /* + * We increment the reference count on node to ensure that + * search->zonecut_rdataset will still be valid later. + */ + new_reference(search->rbtdb, node); + search->zonecut = node; + search->zonecut_rdataset = dname_header; + search->zonecut_sigrdataset = sigdname_header; + search->need_cleanup = ISC_TRUE; + result = DNS_R_PARTIALMATCH; + } else + result = DNS_R_CONTINUE; + + NODE_UNLOCK(lock, locktype); + + return (result); +} + +static inline isc_result_t +find_deepest_zonecut(rbtdb_search_t *search, dns_rbtnode_t *node, + dns_dbnode_t **nodep, dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + unsigned int i; + dns_rbtnode_t *level_node; + rdatasetheader_t *header, *header_prev, *header_next; + rdatasetheader_t *found, *foundsig; + isc_result_t result = ISC_R_NOTFOUND; + dns_name_t name; + dns_rbtdb_t *rbtdb; + isc_boolean_t done; + nodelock_t *lock; + isc_rwlocktype_t locktype; + + /* + * Caller must be holding the tree lock. + */ + + rbtdb = search->rbtdb; + i = search->chain.level_matches; + done = ISC_FALSE; + do { + locktype = isc_rwlocktype_read; + lock = &rbtdb->node_locks[node->locknum].lock; + NODE_LOCK(lock, locktype); + + /* + * Look for NS and RRSIG NS rdatasets. + */ + found = NULL; + foundsig = NULL; + header_prev = NULL; + for (header = node->data; + header != NULL; + header = header_next) { + header_next = header->next; + if (header->ttl <= search->now) { + /* + * This rdataset is stale. If no one else is + * using the node, we can clean it up right + * now, otherwise we mark it as stale, and + * the node as dirty, so it will get cleaned + * up later. + */ + if ((header->ttl <= search->now - + RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only + * when we can get write access. + */ + locktype = isc_rwlocktype_write; + + if (dns_rbtnode_refcurrent(node) + == 0) { + isc_mem_t *m; + + m = search->rbtdb->common.mctx; + clean_stale_headers(m, header); + if (header_prev != NULL) + header_prev->next = + header->next; + else + node->data = + header->next; + free_rdataset(m, header); + } else { + header->attributes |= + RDATASET_ATTR_STALE; + node->dirty = 1; + header_prev = header; + } + } else + header_prev = header; + } else if (EXISTS(header)) { + /* + * We've found an extant rdataset. See if + * we're interested in it. + */ + if (header->type == dns_rdatatype_ns) { + found = header; + if (foundsig != NULL) + break; + } else if (header->type == + RBTDB_RDATATYPE_SIGNS) { + foundsig = header; + if (found != NULL) + break; + } + header_prev = header; + } else + header_prev = header; + } + + if (found != NULL) { + /* + * If we have to set foundname, we do it before + * anything else. If we were to set foundname after + * we had set nodep or bound the rdataset, then we'd + * have to undo that work if dns_name_concatenate() + * failed. By setting foundname first, there's + * nothing to undo if we have trouble. + */ + if (foundname != NULL) { + dns_name_init(&name, NULL); + dns_rbt_namefromnode(node, &name); + result = dns_name_copy(&name, foundname, NULL); + while (result == ISC_R_SUCCESS && i > 0) { + i--; + level_node = search->chain.levels[i]; + dns_name_init(&name, NULL); + dns_rbt_namefromnode(level_node, + &name); + result = + dns_name_concatenate(foundname, + &name, + foundname, + NULL); + } + if (result != ISC_R_SUCCESS) { + *nodep = NULL; + goto node_exit; + } + } + result = DNS_R_DELEGATION; + if (nodep != NULL) { + new_reference(search->rbtdb, node); + *nodep = node; + } + bind_rdataset(search->rbtdb, node, found, search->now, + rdataset); + if (foundsig != NULL) + bind_rdataset(search->rbtdb, node, foundsig, + search->now, sigrdataset); + } + + node_exit: + NODE_UNLOCK(lock, locktype); + + if (found == NULL && i > 0) { + i--; + node = search->chain.levels[i]; + } else + done = ISC_TRUE; + + } while (!done); + + return (result); +} + +static isc_result_t +find_coveringnsec(rbtdb_search_t *search, dns_dbnode_t **nodep, + isc_stdtime_t now, dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + dns_rbtnode_t *node; + rdatasetheader_t *header, *header_next, *header_prev; + rdatasetheader_t *found, *foundsig; + isc_boolean_t empty_node; + isc_result_t result; + dns_fixedname_t fname, forigin; + dns_name_t *name, *origin; + rbtdb_rdatatype_t matchtype, sigmatchtype; + nodelock_t *lock; + isc_rwlocktype_t locktype; + + matchtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_nsec, 0); + sigmatchtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, + dns_rdatatype_nsec); + + do { + node = NULL; + dns_fixedname_init(&fname); + name = dns_fixedname_name(&fname); + dns_fixedname_init(&forigin); + origin = dns_fixedname_name(&forigin); + result = dns_rbtnodechain_current(&search->chain, name, + origin, &node); + if (result != ISC_R_SUCCESS) + return (result); + locktype = isc_rwlocktype_read; + lock = &(search->rbtdb->node_locks[node->locknum].lock); + NODE_LOCK(lock, locktype); + found = NULL; + foundsig = NULL; + empty_node = ISC_TRUE; + header_prev = NULL; + for (header = node->data; + header != NULL; + header = header_next) { + header_next = header->next; + if (header->ttl <= now) { + /* + * This rdataset is stale. If no one else is + * using the node, we can clean it up right + * now, otherwise we mark it as stale, and the + * node as dirty, so it will get cleaned up + * later. + */ + if ((header->ttl <= now - RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only + * when we can get write access. + */ + locktype = isc_rwlocktype_write; + + if (dns_rbtnode_refcurrent(node) + == 0) { + isc_mem_t *m; + + m = search->rbtdb->common.mctx; + clean_stale_headers(m, header); + if (header_prev != NULL) + header_prev->next = + header->next; + else + node->data = header->next; + free_rdataset(m, header); + } else { + header->attributes |= + RDATASET_ATTR_STALE; + node->dirty = 1; + header_prev = header; + } + } else + header_prev = header; + continue; + } + if (NONEXISTENT(header) || + RBTDB_RDATATYPE_BASE(header->type) == 0) { + header_prev = header; + continue; + } + empty_node = ISC_FALSE; + if (header->type == matchtype) + found = header; + else if (header->type == sigmatchtype) + foundsig = header; + header_prev = header; + } + if (found != NULL) { + result = dns_name_concatenate(name, origin, + foundname, NULL); + if (result != ISC_R_SUCCESS) + goto unlock_node; + bind_rdataset(search->rbtdb, node, found, + now, rdataset); + if (foundsig != NULL) + bind_rdataset(search->rbtdb, node, foundsig, + now, sigrdataset); + new_reference(search->rbtdb, node); + *nodep = node; + result = DNS_R_COVERINGNSEC; + } else if (!empty_node) { + result = ISC_R_NOTFOUND; + } else + result = dns_rbtnodechain_prev(&search->chain, NULL, + NULL); + unlock_node: + NODE_UNLOCK(lock, locktype); + } while (empty_node && result == ISC_R_SUCCESS); + return (result); +} + +static isc_result_t +cache_find(dns_db_t *db, dns_name_t *name, dns_dbversion_t *version, + dns_rdatatype_t type, unsigned int options, isc_stdtime_t now, + dns_dbnode_t **nodep, dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + dns_rbtnode_t *node = NULL; + isc_result_t result; + rbtdb_search_t search; + isc_boolean_t cname_ok = ISC_TRUE; + isc_boolean_t empty_node; + nodelock_t *lock; + isc_rwlocktype_t locktype; + rdatasetheader_t *header, *header_prev, *header_next; + rdatasetheader_t *found, *nsheader; + rdatasetheader_t *foundsig, *nssig, *cnamesig; + rbtdb_rdatatype_t sigtype, negtype; + + UNUSED(version); + + search.rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(search.rbtdb)); + REQUIRE(version == NULL); + + if (now == 0) + isc_stdtime_get(&now); + + search.rbtversion = NULL; + search.serial = 1; + search.options = options; + search.copy_name = ISC_FALSE; + search.need_cleanup = ISC_FALSE; + search.wild = ISC_FALSE; + search.zonecut = NULL; + dns_fixedname_init(&search.zonecut_name); + dns_rbtnodechain_init(&search.chain, search.rbtdb->common.mctx); + search.now = now; + + RWLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + /* + * Search down from the root of the tree. If, while going down, we + * encounter a callback node, cache_zonecut_callback() will search the + * rdatasets at the zone cut for a DNAME rdataset. + */ + result = dns_rbt_findnode(search.rbtdb->tree, name, foundname, &node, + &search.chain, DNS_RBTFIND_EMPTYDATA, + cache_zonecut_callback, &search); + + if (result == DNS_R_PARTIALMATCH) { + if ((search.options & DNS_DBFIND_COVERINGNSEC) != 0) { + result = find_coveringnsec(&search, nodep, now, + foundname, rdataset, + sigrdataset); + if (result == DNS_R_COVERINGNSEC) + goto tree_exit; + } + if (search.zonecut != NULL) { + result = setup_delegation(&search, nodep, foundname, + rdataset, sigrdataset); + goto tree_exit; + } else { + find_ns: + result = find_deepest_zonecut(&search, node, nodep, + foundname, rdataset, + sigrdataset); + goto tree_exit; + } + } else if (result != ISC_R_SUCCESS) + goto tree_exit; + + /* + * Certain DNSSEC types are not subject to CNAME matching + * (RFC4035, section 2.5 and RFC3007). + * + * We don't check for RRSIG, because we don't store RRSIG records + * directly. + */ + if (type == dns_rdatatype_key || type == dns_rdatatype_nsec) + cname_ok = ISC_FALSE; + + /* + * We now go looking for rdata... + */ + + lock = &(search.rbtdb->node_locks[node->locknum].lock); + locktype = isc_rwlocktype_read; + NODE_LOCK(lock, locktype); + + found = NULL; + foundsig = NULL; + sigtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, type); + negtype = RBTDB_RDATATYPE_VALUE(0, type); + nsheader = NULL; + nssig = NULL; + cnamesig = NULL; + empty_node = ISC_TRUE; + header_prev = NULL; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->ttl <= now) { + /* + * This rdataset is stale. If no one else is using the + * node, we can clean it up right now, otherwise we + * mark it as stale, and the node as dirty, so it will + * get cleaned up later. + */ + if ((header->ttl <= now - RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only when we + * can get write access. + */ + locktype = isc_rwlocktype_write; + + if (dns_rbtnode_refcurrent(node) == 0) { + isc_mem_t *mctx; + + mctx = search.rbtdb->common.mctx; + clean_stale_headers(mctx, header); + if (header_prev != NULL) + header_prev->next = + header->next; + else + node->data = header->next; + free_rdataset(mctx, header); + } else { + header->attributes |= + RDATASET_ATTR_STALE; + node->dirty = 1; + header_prev = header; + } + } else + header_prev = header; + } else if (EXISTS(header)) { + /* + * We now know that there is at least one active + * non-stale rdataset at this node. + */ + empty_node = ISC_FALSE; + + /* + * If we found a type we were looking for, remember + * it. + */ + if (header->type == type || + (type == dns_rdatatype_any && + RBTDB_RDATATYPE_BASE(header->type) != 0) || + (cname_ok && header->type == + dns_rdatatype_cname)) { + /* + * We've found the answer. + */ + found = header; + if (header->type == dns_rdatatype_cname && + cname_ok && + cnamesig != NULL) { + /* + * If we've already got the CNAME RRSIG, + * use it, otherwise change sigtype + * so that we find it. + */ + if (cnamesig != NULL) + foundsig = cnamesig; + else + sigtype = + RBTDB_RDATATYPE_SIGCNAME; + foundsig = cnamesig; + } + } else if (header->type == sigtype) { + /* + * We've found the RRSIG rdataset for our + * target type. Remember it. + */ + foundsig = header; + } else if (header->type == RBTDB_RDATATYPE_NCACHEANY || + header->type == negtype) { + /* + * We've found a negative cache entry. + */ + found = header; + } else if (header->type == dns_rdatatype_ns) { + /* + * Remember a NS rdataset even if we're + * not specifically looking for it, because + * we might need it later. + */ + nsheader = header; + } else if (header->type == RBTDB_RDATATYPE_SIGNS) { + /* + * If we need the NS rdataset, we'll also + * need its signature. + */ + nssig = header; + } else if (cname_ok && + header->type == RBTDB_RDATATYPE_SIGCNAME) { + /* + * If we get a CNAME match, we'll also need + * its signature. + */ + cnamesig = header; + } + header_prev = header; + } else + header_prev = header; + } + + if (empty_node) { + /* + * We have an exact match for the name, but there are no + * extant rdatasets. That means that this node doesn't + * meaningfully exist, and that we really have a partial match. + */ + NODE_UNLOCK(lock, locktype); + goto find_ns; + } + + /* + * If we didn't find what we were looking for... + */ + if (found == NULL || + (found->trust == dns_trust_glue && + ((options & DNS_DBFIND_GLUEOK) == 0)) || + (found->trust == dns_trust_pending && + ((options & DNS_DBFIND_PENDINGOK) == 0))) { + /* + * If there is an NS rdataset at this node, then this is the + * deepest zone cut. + */ + if (nsheader != NULL) { + if (nodep != NULL) { + new_reference(search.rbtdb, node); + *nodep = node; + } + bind_rdataset(search.rbtdb, node, nsheader, search.now, + rdataset); + if (nssig != NULL) + bind_rdataset(search.rbtdb, node, nssig, + search.now, sigrdataset); + result = DNS_R_DELEGATION; + goto node_exit; + } + + /* + * Go find the deepest zone cut. + */ + NODE_UNLOCK(lock, locktype); + goto find_ns; + } + + /* + * We found what we were looking for, or we found a CNAME. + */ + + if (nodep != NULL) { + new_reference(search.rbtdb, node); + *nodep = node; + } + + if (RBTDB_RDATATYPE_BASE(found->type) == 0) { + /* + * We found a negative cache entry. + */ + if (NXDOMAIN(found)) + result = DNS_R_NCACHENXDOMAIN; + else + result = DNS_R_NCACHENXRRSET; + } else if (type != found->type && + type != dns_rdatatype_any && + found->type == dns_rdatatype_cname) { + /* + * We weren't doing an ANY query and we found a CNAME instead + * of the type we were looking for, so we need to indicate + * that result to the caller. + */ + result = DNS_R_CNAME; + } else { + /* + * An ordinary successful query! + */ + result = ISC_R_SUCCESS; + } + + if (type != dns_rdatatype_any || result == DNS_R_NCACHENXDOMAIN || + result == DNS_R_NCACHENXRRSET) { + bind_rdataset(search.rbtdb, node, found, search.now, + rdataset); + if (foundsig != NULL) + bind_rdataset(search.rbtdb, node, foundsig, search.now, + sigrdataset); + } + + node_exit: + NODE_UNLOCK(lock, locktype); + + tree_exit: + RWUNLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + /* + * If we found a zonecut but aren't going to use it, we have to + * let go of it. + */ + if (search.need_cleanup) { + node = search.zonecut; + lock = &(search.rbtdb->node_locks[node->locknum].lock); + + NODE_LOCK(lock, isc_rwlocktype_read); + decrement_reference(search.rbtdb, node, 0, + isc_rwlocktype_read, isc_rwlocktype_none); + NODE_UNLOCK(lock, isc_rwlocktype_read); + } + + dns_rbtnodechain_reset(&search.chain); + + return (result); +} + +static isc_result_t +cache_findzonecut(dns_db_t *db, dns_name_t *name, unsigned int options, + isc_stdtime_t now, dns_dbnode_t **nodep, + dns_name_t *foundname, + dns_rdataset_t *rdataset, dns_rdataset_t *sigrdataset) +{ + dns_rbtnode_t *node = NULL; + nodelock_t *lock; + isc_result_t result; + rbtdb_search_t search; + rdatasetheader_t *header, *header_prev, *header_next; + rdatasetheader_t *found, *foundsig; + unsigned int rbtoptions = DNS_RBTFIND_EMPTYDATA; + isc_rwlocktype_t locktype; + + search.rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(search.rbtdb)); + + if (now == 0) + isc_stdtime_get(&now); + + search.rbtversion = NULL; + search.serial = 1; + search.options = options; + search.copy_name = ISC_FALSE; + search.need_cleanup = ISC_FALSE; + search.wild = ISC_FALSE; + search.zonecut = NULL; + dns_fixedname_init(&search.zonecut_name); + dns_rbtnodechain_init(&search.chain, search.rbtdb->common.mctx); + search.now = now; + + if ((options & DNS_DBFIND_NOEXACT) != 0) + rbtoptions |= DNS_RBTFIND_NOEXACT; + + RWLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + /* + * Search down from the root of the tree. + */ + result = dns_rbt_findnode(search.rbtdb->tree, name, foundname, &node, + &search.chain, rbtoptions, NULL, &search); + + if (result == DNS_R_PARTIALMATCH) { + find_ns: + result = find_deepest_zonecut(&search, node, nodep, foundname, + rdataset, sigrdataset); + goto tree_exit; + } else if (result != ISC_R_SUCCESS) + goto tree_exit; + + /* + * We now go looking for an NS rdataset at the node. + */ + + lock = &(search.rbtdb->node_locks[node->locknum].lock); + locktype = isc_rwlocktype_read; + NODE_LOCK(lock, locktype); + + found = NULL; + foundsig = NULL; + header_prev = NULL; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->ttl <= now) { + /* + * This rdataset is stale. If no one else is using the + * node, we can clean it up right now, otherwise we + * mark it as stale, and the node as dirty, so it will + * get cleaned up later. + */ + if ((header->ttl <= now - RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only when we + * can get write access. + */ + locktype = isc_rwlocktype_write; + + if (dns_rbtnode_refcurrent(node) == 0) { + isc_mem_t *mctx; + + mctx = search.rbtdb->common.mctx; + clean_stale_headers(mctx, header); + if (header_prev != NULL) + header_prev->next = + header->next; + else + node->data = header->next; + free_rdataset(mctx, header); + } else { + header->attributes |= + RDATASET_ATTR_STALE; + node->dirty = 1; + header_prev = header; + } + } else + header_prev = header; + } else if (EXISTS(header)) { + /* + * If we found a type we were looking for, remember + * it. + */ + if (header->type == dns_rdatatype_ns) { + /* + * Remember a NS rdataset even if we're + * not specifically looking for it, because + * we might need it later. + */ + found = header; + } else if (header->type == RBTDB_RDATATYPE_SIGNS) { + /* + * If we need the NS rdataset, we'll also + * need its signature. + */ + foundsig = header; + } + header_prev = header; + } else + header_prev = header; + } + + if (found == NULL) { + /* + * No NS records here. + */ + NODE_UNLOCK(lock, locktype); + goto find_ns; + } + + if (nodep != NULL) { + new_reference(search.rbtdb, node); + *nodep = node; + } + + bind_rdataset(search.rbtdb, node, found, search.now, rdataset); + if (foundsig != NULL) + bind_rdataset(search.rbtdb, node, foundsig, search.now, + sigrdataset); + + NODE_UNLOCK(lock, locktype); + + tree_exit: + RWUNLOCK(&search.rbtdb->tree_lock, isc_rwlocktype_read); + + INSIST(!search.need_cleanup); + + dns_rbtnodechain_reset(&search.chain); + + if (result == DNS_R_DELEGATION) + result = ISC_R_SUCCESS; + + return (result); +} + +static void +attachnode(dns_db_t *db, dns_dbnode_t *source, dns_dbnode_t **targetp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *node = (dns_rbtnode_t *)source; + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(targetp != NULL && *targetp == NULL); + + NODE_STRONGLOCK(&rbtdb->node_locks[node->locknum].lock); + dns_rbtnode_refincrement(node, &refs); + INSIST(refs != 0); + NODE_STRONGUNLOCK(&rbtdb->node_locks[node->locknum].lock); + + *targetp = source; +} + +static void +detachnode(dns_db_t *db, dns_dbnode_t **targetp) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *node; + isc_boolean_t want_free = ISC_FALSE; + isc_boolean_t inactive = ISC_FALSE; + rbtdb_nodelock_t *nodelock; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(targetp != NULL && *targetp != NULL); + + node = (dns_rbtnode_t *)(*targetp); + nodelock = &rbtdb->node_locks[node->locknum]; + + NODE_LOCK(&nodelock->lock, isc_rwlocktype_read); + + if (decrement_reference(rbtdb, node, 0, isc_rwlocktype_read, + isc_rwlocktype_none)) { + if (isc_refcount_current(&nodelock->references) == 0 && + nodelock->exiting) { + inactive = ISC_TRUE; + } + } + + NODE_UNLOCK(&nodelock->lock, isc_rwlocktype_read); + + *targetp = NULL; + + if (inactive) { + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + rbtdb->active--; + if (rbtdb->active == 0) + want_free = ISC_TRUE; + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + if (want_free) { + char buf[DNS_NAME_FORMATSIZE]; + if (dns_name_dynamic(&rbtdb->common.origin)) + dns_name_format(&rbtdb->common.origin, buf, + sizeof(buf)); + else + strcpy(buf, "<UNKNOWN>"); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_DEBUG(1), + "calling free_rbtdb(%s)", buf); + free_rbtdb(rbtdb, ISC_TRUE, NULL); + } + } +} + +static isc_result_t +expirenode(dns_db_t *db, dns_dbnode_t *node, isc_stdtime_t now) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = node; + rdatasetheader_t *header; + isc_boolean_t force_expire = ISC_FALSE; + /* + * These are the category and module used by the cache cleaner. + */ + isc_boolean_t log = ISC_FALSE; + isc_logcategory_t *category = DNS_LOGCATEGORY_DATABASE; + isc_logmodule_t *module = DNS_LOGMODULE_CACHE; + int level = ISC_LOG_DEBUG(2); + char printname[DNS_NAME_FORMATSIZE]; + + REQUIRE(VALID_RBTDB(rbtdb)); + + /* + * Caller must hold a tree lock. + */ + + if (now == 0) + isc_stdtime_get(&now); + + if (rbtdb->overmem) { + isc_uint32_t val; + + isc_random_get(&val); + /* + * XXXDCL Could stand to have a better policy, like LRU. + */ + force_expire = ISC_TF(rbtnode->down == NULL && val % 4 == 0); + + /* + * Note that 'log' can be true IFF rbtdb->overmem is also true. + * rbtdb->ovemem can currently only be true for cache databases + * -- hence all of the "overmem cache" log strings. + */ + log = ISC_TF(isc_log_wouldlog(dns_lctx, level)); + if (log) + isc_log_write(dns_lctx, category, module, level, + "overmem cache: %s %s", + force_expire ? "FORCE" : "check", + dns_rbt_formatnodename(rbtnode, + printname, + sizeof(printname))); + } + + /* + * We may not need write access, but this code path is not performance + * sensitive, so it should be okay to always lock as a writer. + */ + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + for (header = rbtnode->data; header != NULL; header = header->next) + if (header->ttl <= now - RBTDB_VIRTUAL) { + /* + * We don't check if refcurrent(rbtnode) == 0 and try + * to free like we do in cache_find(), because + * refcurrent(rbtnode) must be non-zero. This is so + * because 'node' is an argument to the function. + */ + header->attributes |= RDATASET_ATTR_STALE; + rbtnode->dirty = 1; + if (log) + isc_log_write(dns_lctx, category, module, + level, "overmem cache: stale %s", + printname); + } else if (force_expire) { + if (! RETAIN(header)) { + header->ttl = 0; + header->attributes |= RDATASET_ATTR_STALE; + rbtnode->dirty = 1; + } else if (log) { + isc_log_write(dns_lctx, category, module, + level, "overmem cache: " + "reprieve by RETAIN() %s", + printname); + } + } else if (rbtdb->overmem && log) + isc_log_write(dns_lctx, category, module, level, + "overmem cache: saved %s", printname); + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + return (ISC_R_SUCCESS); +} + +static void +overmem(dns_db_t *db, isc_boolean_t overmem) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + + if (IS_CACHE(rbtdb)) { + rbtdb->overmem = overmem; + } +} + +static void +printnode(dns_db_t *db, dns_dbnode_t *node, FILE *out) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = node; + isc_boolean_t first; + + REQUIRE(VALID_RBTDB(rbtdb)); + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + fprintf(out, "node %p, %u references, locknum = %u\n", + rbtnode, dns_rbtnode_refcurrent(rbtnode), + rbtnode->locknum); + if (rbtnode->data != NULL) { + rdatasetheader_t *current, *top_next; + + for (current = rbtnode->data; current != NULL; + current = top_next) { + top_next = current->next; + first = ISC_TRUE; + fprintf(out, "\ttype %u", current->type); + do { + if (!first) + fprintf(out, "\t"); + first = ISC_FALSE; + fprintf(out, + "\tserial = %lu, ttl = %u, " + "trust = %u, attributes = %u\n", + (unsigned long)current->serial, + current->ttl, + current->trust, + current->attributes); + current = current->down; + } while (current != NULL); + } + } else + fprintf(out, "(empty)\n"); + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); +} + +static isc_result_t +createiterator(dns_db_t *db, isc_boolean_t relative_names, + dns_dbiterator_t **iteratorp) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + rbtdb_dbiterator_t *rbtdbiter; + + REQUIRE(VALID_RBTDB(rbtdb)); + + rbtdbiter = isc_mem_get(rbtdb->common.mctx, sizeof(*rbtdbiter)); + if (rbtdbiter == NULL) + return (ISC_R_NOMEMORY); + + rbtdbiter->common.methods = &dbiterator_methods; + rbtdbiter->common.db = NULL; + dns_db_attach(db, &rbtdbiter->common.db); + rbtdbiter->common.relative_names = relative_names; + rbtdbiter->common.magic = DNS_DBITERATOR_MAGIC; + rbtdbiter->common.cleaning = ISC_FALSE; + rbtdbiter->paused = ISC_TRUE; + rbtdbiter->tree_locked = isc_rwlocktype_none; + rbtdbiter->result = ISC_R_SUCCESS; + dns_fixedname_init(&rbtdbiter->name); + dns_fixedname_init(&rbtdbiter->origin); + rbtdbiter->node = NULL; + rbtdbiter->delete = 0; + memset(rbtdbiter->deletions, 0, sizeof(rbtdbiter->deletions)); + dns_rbtnodechain_init(&rbtdbiter->chain, db->mctx); + + *iteratorp = (dns_dbiterator_t *)rbtdbiter; + + return (ISC_R_SUCCESS); +} + +static isc_result_t +zone_findrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + dns_rdatatype_t type, dns_rdatatype_t covers, + isc_stdtime_t now, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rdatasetheader_t *header, *header_next, *found, *foundsig; + rbtdb_serial_t serial; + rbtdb_version_t *rbtversion = version; + isc_boolean_t close_version = ISC_FALSE; + rbtdb_rdatatype_t matchtype, sigmatchtype; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(type != dns_rdatatype_any); + + if (rbtversion == NULL) { + currentversion(db, (dns_dbversion_t **) (void *)(&rbtversion)); + close_version = ISC_TRUE; + } + serial = rbtversion->serial; + now = 0; + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + found = NULL; + foundsig = NULL; + matchtype = RBTDB_RDATATYPE_VALUE(type, covers); + if (covers == 0) + sigmatchtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, type); + else + sigmatchtype = 0; + + for (header = rbtnode->data; header != NULL; header = header_next) { + header_next = header->next; + do { + if (header->serial <= serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) { + /* + * We have an active, extant rdataset. If it's a + * type we're looking for, remember it. + */ + if (header->type == matchtype) { + found = header; + if (foundsig != NULL) + break; + } else if (header->type == sigmatchtype) { + foundsig = header; + if (found != NULL) + break; + } + } + } + if (found != NULL) { + bind_rdataset(rbtdb, rbtnode, found, now, rdataset); + if (foundsig != NULL) + bind_rdataset(rbtdb, rbtnode, foundsig, now, + sigrdataset); + } + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + if (close_version) + closeversion(db, (dns_dbversion_t **) (void *)(&rbtversion), + ISC_FALSE); + + if (found == NULL) + return (ISC_R_NOTFOUND); + + return (ISC_R_SUCCESS); +} + +static isc_result_t +cache_findrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + dns_rdatatype_t type, dns_rdatatype_t covers, + isc_stdtime_t now, dns_rdataset_t *rdataset, + dns_rdataset_t *sigrdataset) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rdatasetheader_t *header, *header_next, *found, *foundsig; + rbtdb_rdatatype_t matchtype, sigmatchtype, negtype; + isc_result_t result; + nodelock_t *lock; + isc_rwlocktype_t locktype; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(type != dns_rdatatype_any); + + UNUSED(version); + + result = ISC_R_SUCCESS; + + if (now == 0) + isc_stdtime_get(&now); + + lock = &rbtdb->node_locks[rbtnode->locknum].lock; + locktype = isc_rwlocktype_read; + NODE_LOCK(lock, locktype); + + found = NULL; + foundsig = NULL; + matchtype = RBTDB_RDATATYPE_VALUE(type, covers); + negtype = RBTDB_RDATATYPE_VALUE(0, type); + if (covers == 0) + sigmatchtype = RBTDB_RDATATYPE_VALUE(dns_rdatatype_rrsig, type); + else + sigmatchtype = 0; + + for (header = rbtnode->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->ttl <= now) { + if ((header->ttl <= now - RBTDB_VIRTUAL) && + (locktype == isc_rwlocktype_write || + NODE_TRYUPGRADE(lock) == ISC_R_SUCCESS)) { + /* + * We update the node's status only when we + * can get write access. + */ + locktype = isc_rwlocktype_write; + + /* + * We don't check if refcurrent(rbtnode) == 0 + * and try to free like we do in cache_find(), + * because refcurrent(rbtnode) must be + * non-zero. This is so because 'node' is an + * argument to the function. + */ + header->attributes |= RDATASET_ATTR_STALE; + rbtnode->dirty = 1; + } + } else if (EXISTS(header)) { + if (header->type == matchtype) + found = header; + else if (header->type == RBTDB_RDATATYPE_NCACHEANY || + header->type == negtype) + found = header; + else if (header->type == sigmatchtype) + foundsig = header; + } + } + if (found != NULL) { + bind_rdataset(rbtdb, rbtnode, found, now, rdataset); + if (foundsig != NULL) + bind_rdataset(rbtdb, rbtnode, foundsig, now, + sigrdataset); + } + + NODE_UNLOCK(lock, locktype); + + if (found == NULL) + return (ISC_R_NOTFOUND); + + if (RBTDB_RDATATYPE_BASE(found->type) == 0) { + /* + * We found a negative cache entry. + */ + if (NXDOMAIN(found)) + result = DNS_R_NCACHENXDOMAIN; + else + result = DNS_R_NCACHENXRRSET; + } + + return (result); +} + +static isc_result_t +allrdatasets(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + isc_stdtime_t now, dns_rdatasetiter_t **iteratorp) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rbtdb_version_t *rbtversion = version; + rbtdb_rdatasetiter_t *iterator; + unsigned int refs; + + REQUIRE(VALID_RBTDB(rbtdb)); + + iterator = isc_mem_get(rbtdb->common.mctx, sizeof(*iterator)); + if (iterator == NULL) + return (ISC_R_NOMEMORY); + + if ((db->attributes & DNS_DBATTR_CACHE) == 0) { + now = 0; + if (rbtversion == NULL) + currentversion(db, + (dns_dbversion_t **) (void *)(&rbtversion)); + else { + unsigned int refs; + + isc_refcount_increment(&rbtversion->references, + &refs); + INSIST(refs > 1); + } + } else { + if (now == 0) + isc_stdtime_get(&now); + rbtversion = NULL; + } + + iterator->common.magic = DNS_RDATASETITER_MAGIC; + iterator->common.methods = &rdatasetiter_methods; + iterator->common.db = db; + iterator->common.node = node; + iterator->common.version = (dns_dbversion_t *)rbtversion; + iterator->common.now = now; + + NODE_STRONGLOCK(&rbtdb->node_locks[rbtnode->locknum].lock); + + dns_rbtnode_refincrement(rbtnode, &refs); + INSIST(refs != 0); + + iterator->current = NULL; + + NODE_STRONGUNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock); + + *iteratorp = (dns_rdatasetiter_t *)iterator; + + return (ISC_R_SUCCESS); +} + +static isc_boolean_t +cname_and_other_data(dns_rbtnode_t *node, rbtdb_serial_t serial) { + rdatasetheader_t *header, *header_next; + isc_boolean_t cname, other_data; + dns_rdatatype_t rdtype; + + /* + * The caller must hold the node lock. + */ + + /* + * Look for CNAME and "other data" rdatasets active in our version. + */ + cname = ISC_FALSE; + other_data = ISC_FALSE; + for (header = node->data; header != NULL; header = header_next) { + header_next = header->next; + if (header->type == dns_rdatatype_cname) { + /* + * Look for an active extant CNAME. + */ + do { + if (header->serial <= serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) + cname = ISC_TRUE; + } else { + /* + * Look for active extant "other data". + * + * "Other data" is any rdataset whose type is not + * KEY, RRSIG KEY, NSEC, RRSIG NSEC or RRSIG CNAME. + */ + rdtype = RBTDB_RDATATYPE_BASE(header->type); + if (rdtype == dns_rdatatype_rrsig || + rdtype == dns_rdatatype_sig) + rdtype = RBTDB_RDATATYPE_EXT(header->type); + if (rdtype != dns_rdatatype_nsec && + rdtype != dns_rdatatype_key && + rdtype != dns_rdatatype_cname) { + /* + * We've found a type that isn't + * NSEC, KEY, CNAME, or one of their + * signatures. Is it active and extant? + */ + do { + if (header->serial <= serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset + * doesn't exist" record? + */ + if (NONEXISTENT(header)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) + other_data = ISC_TRUE; + } + } + } + + if (cname && other_data) + return (ISC_TRUE); + + return (ISC_FALSE); +} + +static isc_result_t +add(dns_rbtdb_t *rbtdb, dns_rbtnode_t *rbtnode, rbtdb_version_t *rbtversion, + rdatasetheader_t *newheader, unsigned int options, isc_boolean_t loading, + dns_rdataset_t *addedrdataset, isc_stdtime_t now) +{ + rbtdb_changed_t *changed = NULL; + rdatasetheader_t *topheader, *topheader_prev, *header; + unsigned char *merged; + isc_result_t result; + isc_boolean_t header_nx; + isc_boolean_t newheader_nx; + isc_boolean_t merge; + dns_rdatatype_t rdtype, covers; + rbtdb_rdatatype_t negtype; + dns_trust_t trust; + + /* + * Add an rdatasetheader_t to a node. + */ + + /* + * Caller must be holding the node lock. + */ + + if ((options & DNS_DBADD_MERGE) != 0) { + REQUIRE(rbtversion != NULL); + merge = ISC_TRUE; + } else + merge = ISC_FALSE; + + if ((options & DNS_DBADD_FORCE) != 0) + trust = dns_trust_ultimate; + else + trust = newheader->trust; + + if (rbtversion != NULL && !loading) { + /* + * We always add a changed record, even if no changes end up + * being made to this node, because it's harmless and + * simplifies the code. + */ + changed = add_changed(rbtdb, rbtversion, rbtnode); + if (changed == NULL) { + free_rdataset(rbtdb->common.mctx, newheader); + return (ISC_R_NOMEMORY); + } + } + + newheader_nx = NONEXISTENT(newheader) ? ISC_TRUE : ISC_FALSE; + topheader_prev = NULL; + + negtype = 0; + if (rbtversion == NULL && !newheader_nx) { + rdtype = RBTDB_RDATATYPE_BASE(newheader->type); + if (rdtype == 0) { + /* + * We're adding a negative cache entry. + */ + covers = RBTDB_RDATATYPE_EXT(newheader->type); + if (covers == dns_rdatatype_any) { + /* + * We're adding an negative cache entry + * which covers all types (NXDOMAIN, + * NODATA(QTYPE=ANY)). + * + * We make all other data stale so that the + * only rdataset that can be found at this + * node is the negative cache entry. + */ + for (topheader = rbtnode->data; + topheader != NULL; + topheader = topheader->next) { + topheader->ttl = 0; + topheader->attributes |= + RDATASET_ATTR_STALE; + } + rbtnode->dirty = 1; + goto find_header; + } + negtype = RBTDB_RDATATYPE_VALUE(covers, 0); + } else { + /* + * We're adding something that isn't a + * negative cache entry. Look for an extant + * non-stale NXDOMAIN/NODATA(QTYPE=ANY) negative + * cache entry. + */ + for (topheader = rbtnode->data; + topheader != NULL; + topheader = topheader->next) { + if (topheader->type == + RBTDB_RDATATYPE_NCACHEANY) + break; + } + if (topheader != NULL && EXISTS(topheader) && + topheader->ttl > now) { + /* + * Found one. + */ + if (trust < topheader->trust) { + /* + * The NXDOMAIN/NODATA(QTYPE=ANY) + * is more trusted. + */ + + free_rdataset(rbtdb->common.mctx, + newheader); + if (addedrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, + topheader, now, + addedrdataset); + return (DNS_R_UNCHANGED); + } + /* + * The new rdataset is better. Expire the + * NXDOMAIN/NODATA(QTYPE=ANY). + */ + topheader->ttl = 0; + topheader->attributes |= RDATASET_ATTR_STALE; + rbtnode->dirty = 1; + topheader = NULL; + goto find_header; + } + negtype = RBTDB_RDATATYPE_VALUE(0, rdtype); + } + } + + for (topheader = rbtnode->data; + topheader != NULL; + topheader = topheader->next) { + if (topheader->type == newheader->type || + topheader->type == negtype) + break; + topheader_prev = topheader; + } + + find_header: + /* + * If header isn't NULL, we've found the right type. There may be + * IGNORE rdatasets between the top of the chain and the first real + * data. We skip over them. + */ + header = topheader; + while (header != NULL && IGNORE(header)) + header = header->down; + if (header != NULL) { + header_nx = NONEXISTENT(header) ? ISC_TRUE : ISC_FALSE; + + /* + * Deleting an already non-existent rdataset has no effect. + */ + if (header_nx && newheader_nx) { + free_rdataset(rbtdb->common.mctx, newheader); + return (DNS_R_UNCHANGED); + } + + /* + * Trying to add an rdataset with lower trust to a cache DB + * has no effect, provided that the cache data isn't stale. + */ + if (rbtversion == NULL && trust < header->trust && + (header->ttl > now || header_nx)) { + free_rdataset(rbtdb->common.mctx, newheader); + if (addedrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, header, now, + addedrdataset); + return (DNS_R_UNCHANGED); + } + + /* + * Don't merge if a nonexistent rdataset is involved. + */ + if (merge && (header_nx || newheader_nx)) + merge = ISC_FALSE; + + /* + * If 'merge' is ISC_TRUE, we'll try to create a new rdataset + * that is the union of 'newheader' and 'header'. + */ + if (merge) { + unsigned int flags = 0; + INSIST(rbtversion->serial >= header->serial); + merged = NULL; + result = ISC_R_SUCCESS; + + if ((options & DNS_DBADD_EXACT) != 0) + flags |= DNS_RDATASLAB_EXACT; + if ((options & DNS_DBADD_EXACTTTL) != 0 && + newheader->ttl != header->ttl) + result = DNS_R_NOTEXACT; + else if (newheader->ttl != header->ttl) + flags |= DNS_RDATASLAB_FORCE; + if (result == ISC_R_SUCCESS) + result = dns_rdataslab_merge( + (unsigned char *)header, + (unsigned char *)newheader, + (unsigned int)(sizeof(*newheader)), + rbtdb->common.mctx, + rbtdb->common.rdclass, + (dns_rdatatype_t)header->type, + flags, &merged); + if (result == ISC_R_SUCCESS) { + /* + * If 'header' has the same serial number as + * we do, we could clean it up now if we knew + * that our caller had no references to it. + * We don't know this, however, so we leave it + * alone. It will get cleaned up when + * clean_zone_node() runs. + */ + free_rdataset(rbtdb->common.mctx, newheader); + newheader = (rdatasetheader_t *)merged; + } else { + free_rdataset(rbtdb->common.mctx, newheader); + return (result); + } + } + /* + * Don't replace existing NS, A and AAAA RRsets + * in the cache if they are already exist. This + * prevents named being locked to old servers. + * Don't lower trust of existing record if the + * update is forced. + */ + if (IS_CACHE(rbtdb) && header->ttl > now && + header->type == dns_rdatatype_ns && + !header_nx && !newheader_nx && + header->trust >= newheader->trust && + dns_rdataslab_equalx((unsigned char *)header, + (unsigned char *)newheader, + (unsigned int)(sizeof(*newheader)), + rbtdb->common.rdclass, + (dns_rdatatype_t)header->type)) { + /* + * Honour the new ttl if it is less than the + * older one. + */ + if (header->ttl > newheader->ttl) + header->ttl = newheader->ttl; + if (header->noqname == NULL && + newheader->noqname != NULL) { + header->noqname = newheader->noqname; + newheader->noqname = NULL; + } + free_rdataset(rbtdb->common.mctx, newheader); + if (addedrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, header, now, + addedrdataset); + return (ISC_R_SUCCESS); + } + if (IS_CACHE(rbtdb) && header->ttl > now && + (header->type == dns_rdatatype_a || + header->type == dns_rdatatype_aaaa) && + !header_nx && !newheader_nx && + header->trust >= newheader->trust && + dns_rdataslab_equal((unsigned char *)header, + (unsigned char *)newheader, + (unsigned int)(sizeof(*newheader)))) { + /* + * Honour the new ttl if it is less than the + * older one. + */ + if (header->ttl > newheader->ttl) + header->ttl = newheader->ttl; + if (header->noqname == NULL && + newheader->noqname != NULL) { + header->noqname = newheader->noqname; + newheader->noqname = NULL; + } + free_rdataset(rbtdb->common.mctx, newheader); + if (addedrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, header, now, + addedrdataset); + return (ISC_R_SUCCESS); + } + INSIST(rbtversion == NULL || + rbtversion->serial >= topheader->serial); + if (topheader_prev != NULL) + topheader_prev->next = newheader; + else + rbtnode->data = newheader; + newheader->next = topheader->next; + if (loading) { + /* + * There are no other references to 'header' when + * loading, so we MAY clean up 'header' now. + * Since we don't generate changed records when + * loading, we MUST clean up 'header' now. + */ + newheader->down = NULL; + free_rdataset(rbtdb->common.mctx, header); + } else { + newheader->down = topheader; + topheader->next = newheader; + rbtnode->dirty = 1; + if (changed != NULL) + changed->dirty = ISC_TRUE; + if (rbtversion == NULL) { + header->ttl = 0; + header->attributes |= RDATASET_ATTR_STALE; + } + } + } else { + /* + * No non-IGNORED rdatasets of the given type exist at + * this node. + */ + + /* + * If we're trying to delete the type, don't bother. + */ + if (newheader_nx) { + free_rdataset(rbtdb->common.mctx, newheader); + return (DNS_R_UNCHANGED); + } + + if (topheader != NULL) { + /* + * We have an list of rdatasets of the given type, + * but they're all marked IGNORE. We simply insert + * the new rdataset at the head of the list. + * + * Ignored rdatasets cannot occur during loading, so + * we INSIST on it. + */ + INSIST(!loading); + INSIST(rbtversion == NULL || + rbtversion->serial >= topheader->serial); + if (topheader_prev != NULL) + topheader_prev->next = newheader; + else + rbtnode->data = newheader; + newheader->next = topheader->next; + newheader->down = topheader; + topheader->next = newheader; + rbtnode->dirty = 1; + if (changed != NULL) + changed->dirty = ISC_TRUE; + } else { + /* + * No rdatasets of the given type exist at the node. + */ + newheader->next = rbtnode->data; + newheader->down = NULL; + rbtnode->data = newheader; + } + } + + /* + * Check if the node now contains CNAME and other data. + */ + if (rbtversion != NULL && + cname_and_other_data(rbtnode, rbtversion->serial)) + return (DNS_R_CNAMEANDOTHER); + + if (addedrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, newheader, now, addedrdataset); + + return (ISC_R_SUCCESS); +} + +static inline isc_boolean_t +delegating_type(dns_rbtdb_t *rbtdb, dns_rbtnode_t *node, + rbtdb_rdatatype_t type) +{ + if (IS_CACHE(rbtdb)) { + if (type == dns_rdatatype_dname) + return (ISC_TRUE); + else + return (ISC_FALSE); + } else if (type == dns_rdatatype_dname || + (type == dns_rdatatype_ns && + (node != rbtdb->origin_node || IS_STUB(rbtdb)))) + return (ISC_TRUE); + return (ISC_FALSE); +} + +static inline isc_result_t +addnoqname(dns_rbtdb_t *rbtdb, rdatasetheader_t *newheader, + dns_rdataset_t *rdataset) +{ + struct noqname *noqname; + isc_mem_t *mctx = rbtdb->common.mctx; + dns_name_t name; + dns_rdataset_t nsec, nsecsig; + isc_result_t result; + isc_region_t r; + + dns_name_init(&name, NULL); + dns_rdataset_init(&nsec); + dns_rdataset_init(&nsecsig); + + result = dns_rdataset_getnoqname(rdataset, &name, &nsec, &nsecsig); + RUNTIME_CHECK(result == ISC_R_SUCCESS); + + noqname = isc_mem_get(mctx, sizeof(*noqname)); + if (noqname == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + dns_name_init(&noqname->name, NULL); + noqname->nsec = NULL; + noqname->nsecsig = NULL; + result = dns_name_dup(&name, mctx, &noqname->name); + if (result != ISC_R_SUCCESS) + goto cleanup; + result = dns_rdataslab_fromrdataset(&nsec, mctx, &r, 0); + if (result != ISC_R_SUCCESS) + goto cleanup; + noqname->nsec = r.base; + result = dns_rdataslab_fromrdataset(&nsecsig, mctx, &r, 0); + if (result != ISC_R_SUCCESS) + goto cleanup; + noqname->nsecsig = r.base; + dns_rdataset_disassociate(&nsec); + dns_rdataset_disassociate(&nsecsig); + newheader->noqname = noqname; + return (ISC_R_SUCCESS); + +cleanup: + dns_rdataset_disassociate(&nsec); + dns_rdataset_disassociate(&nsecsig); + free_noqname(mctx, &noqname); + return(result); +} + +static isc_result_t +addrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + isc_stdtime_t now, dns_rdataset_t *rdataset, unsigned int options, + dns_rdataset_t *addedrdataset) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rbtdb_version_t *rbtversion = version; + isc_region_t region; + rdatasetheader_t *newheader; + isc_result_t result; + isc_boolean_t delegating; + + REQUIRE(VALID_RBTDB(rbtdb)); + + if (rbtversion == NULL) { + if (now == 0) + isc_stdtime_get(&now); + } else + now = 0; + + result = dns_rdataslab_fromrdataset(rdataset, rbtdb->common.mctx, + ®ion, + sizeof(rdatasetheader_t)); + if (result != ISC_R_SUCCESS) + return (result); + + newheader = (rdatasetheader_t *)region.base; + newheader->ttl = rdataset->ttl + now; + newheader->type = RBTDB_RDATATYPE_VALUE(rdataset->type, + rdataset->covers); + newheader->attributes = 0; + newheader->noqname = NULL; + newheader->count = init_count++; + newheader->trust = rdataset->trust; + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + if (rbtversion != NULL) { + newheader->serial = rbtversion->serial; + now = 0; + } else { + newheader->serial = 1; + if ((rdataset->attributes & DNS_RDATASETATTR_NXDOMAIN) != 0) + newheader->attributes |= RDATASET_ATTR_NXDOMAIN; + if ((rdataset->attributes & DNS_RDATASETATTR_NOQNAME) != 0) { + result = addnoqname(rbtdb, newheader, rdataset); + if (result != ISC_R_SUCCESS) { + free_rdataset(rbtdb->common.mctx, newheader); + return (result); + } + } + } + + /* + * If we're adding a delegation type (e.g. NS or DNAME for a zone, + * just DNAME for the cache), then we need to set the callback bit + * on the node, and to do that we must be holding an exclusive lock + * on the tree. + */ + if (delegating_type(rbtdb, rbtnode, rdataset->type)) { + delegating = ISC_TRUE; + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_write); + } else + delegating = ISC_FALSE; + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + result = add(rbtdb, rbtnode, rbtversion, newheader, options, ISC_FALSE, + addedrdataset, now); + if (result == ISC_R_SUCCESS && delegating) + rbtnode->find_callback = 1; + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + if (delegating) + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_write); + + /* + * Update the zone's secure status. If version is non-NULL + * this is defered until closeversion() is called. + */ + if (result == ISC_R_SUCCESS && version == NULL && !IS_CACHE(rbtdb)) + rbtdb->secure = iszonesecure(db, rbtdb->origin_node); + + return (result); +} + +static isc_result_t +subtractrdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + dns_rdataset_t *rdataset, unsigned int options, + dns_rdataset_t *newrdataset) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rbtdb_version_t *rbtversion = version; + rdatasetheader_t *topheader, *topheader_prev, *header, *newheader; + unsigned char *subresult; + isc_region_t region; + isc_result_t result; + rbtdb_changed_t *changed; + + REQUIRE(VALID_RBTDB(rbtdb)); + + result = dns_rdataslab_fromrdataset(rdataset, rbtdb->common.mctx, + ®ion, + sizeof(rdatasetheader_t)); + if (result != ISC_R_SUCCESS) + return (result); + newheader = (rdatasetheader_t *)region.base; + newheader->ttl = rdataset->ttl; + newheader->type = RBTDB_RDATATYPE_VALUE(rdataset->type, + rdataset->covers); + newheader->attributes = 0; + newheader->serial = rbtversion->serial; + newheader->trust = 0; + newheader->noqname = NULL; + newheader->count = init_count++; + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + changed = add_changed(rbtdb, rbtversion, rbtnode); + if (changed == NULL) { + free_rdataset(rbtdb->common.mctx, newheader); + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + return (ISC_R_NOMEMORY); + } + + topheader_prev = NULL; + for (topheader = rbtnode->data; + topheader != NULL; + topheader = topheader->next) { + if (topheader->type == newheader->type) + break; + topheader_prev = topheader; + } + /* + * If header isn't NULL, we've found the right type. There may be + * IGNORE rdatasets between the top of the chain and the first real + * data. We skip over them. + */ + header = topheader; + while (header != NULL && IGNORE(header)) + header = header->down; + if (header != NULL && EXISTS(header)) { + unsigned int flags = 0; + subresult = NULL; + result = ISC_R_SUCCESS; + if ((options & DNS_DBSUB_EXACT) != 0) { + flags |= DNS_RDATASLAB_EXACT; + if (newheader->ttl != header->ttl) + result = DNS_R_NOTEXACT; + } + if (result == ISC_R_SUCCESS) + result = dns_rdataslab_subtract( + (unsigned char *)header, + (unsigned char *)newheader, + (unsigned int)(sizeof(*newheader)), + rbtdb->common.mctx, + rbtdb->common.rdclass, + (dns_rdatatype_t)header->type, + flags, &subresult); + if (result == ISC_R_SUCCESS) { + free_rdataset(rbtdb->common.mctx, newheader); + newheader = (rdatasetheader_t *)subresult; + /* + * We have to set the serial since the rdataslab + * subtraction routine copies the reserved portion of + * header, not newheader. + */ + newheader->serial = rbtversion->serial; + /* + * XXXJT: dns_rdataslab_subtract() copied the pointers + * to additional info. We need to clear these fields + * to avoid having duplicated references. + */ + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + } else if (result == DNS_R_NXRRSET) { + /* + * This subtraction would remove all of the rdata; + * add a nonexistent header instead. + */ + free_rdataset(rbtdb->common.mctx, newheader); + newheader = isc_mem_get(rbtdb->common.mctx, + sizeof(*newheader)); + if (newheader == NULL) { + result = ISC_R_NOMEMORY; + goto unlock; + } + newheader->ttl = 0; + newheader->type = topheader->type; + newheader->attributes = RDATASET_ATTR_NONEXISTENT; + newheader->trust = 0; + newheader->serial = rbtversion->serial; + newheader->noqname = NULL; + newheader->count = 0; + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + } else { + free_rdataset(rbtdb->common.mctx, newheader); + goto unlock; + } + + /* + * If we're here, we want to link newheader in front of + * topheader. + */ + INSIST(rbtversion->serial >= topheader->serial); + if (topheader_prev != NULL) + topheader_prev->next = newheader; + else + rbtnode->data = newheader; + newheader->next = topheader->next; + newheader->down = topheader; + topheader->next = newheader; + rbtnode->dirty = 1; + changed->dirty = ISC_TRUE; + } else { + /* + * The rdataset doesn't exist, so we don't need to do anything + * to satisfy the deletion request. + */ + free_rdataset(rbtdb->common.mctx, newheader); + if ((options & DNS_DBSUB_EXACT) != 0) + result = DNS_R_NOTEXACT; + else + result = DNS_R_UNCHANGED; + } + + if (result == ISC_R_SUCCESS && newrdataset != NULL) + bind_rdataset(rbtdb, rbtnode, newheader, 0, newrdataset); + + unlock: + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + /* + * Update the zone's secure status. If version is non-NULL + * this is defered until closeversion() is called. + */ + if (result == ISC_R_SUCCESS && version == NULL && !IS_CACHE(rbtdb)) + rbtdb->secure = iszonesecure(db, rbtdb->origin_node); + + return (result); +} + +static isc_result_t +deleterdataset(dns_db_t *db, dns_dbnode_t *node, dns_dbversion_t *version, + dns_rdatatype_t type, dns_rdatatype_t covers) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *rbtnode = (dns_rbtnode_t *)node; + rbtdb_version_t *rbtversion = version; + isc_result_t result; + rdatasetheader_t *newheader; + + REQUIRE(VALID_RBTDB(rbtdb)); + + if (type == dns_rdatatype_any) + return (ISC_R_NOTIMPLEMENTED); + if (type == dns_rdatatype_rrsig && covers == 0) + return (ISC_R_NOTIMPLEMENTED); + + newheader = isc_mem_get(rbtdb->common.mctx, sizeof(*newheader)); + if (newheader == NULL) + return (ISC_R_NOMEMORY); + newheader->ttl = 0; + newheader->type = RBTDB_RDATATYPE_VALUE(type, covers); + newheader->attributes = RDATASET_ATTR_NONEXISTENT; + newheader->trust = 0; + newheader->noqname = NULL; + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + if (rbtversion != NULL) + newheader->serial = rbtversion->serial; + else + newheader->serial = 0; + newheader->count = 0; + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + result = add(rbtdb, rbtnode, rbtversion, newheader, DNS_DBADD_FORCE, + ISC_FALSE, NULL, 0); + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_write); + + /* + * Update the zone's secure status. If version is non-NULL + * this is defered until closeversion() is called. + */ + if (result == ISC_R_SUCCESS && version == NULL && !IS_CACHE(rbtdb)) + rbtdb->secure = iszonesecure(db, rbtdb->origin_node); + + return (result); +} + +static isc_result_t +loading_addrdataset(void *arg, dns_name_t *name, dns_rdataset_t *rdataset) { + rbtdb_load_t *loadctx = arg; + dns_rbtdb_t *rbtdb = loadctx->rbtdb; + dns_rbtnode_t *node; + isc_result_t result; + isc_region_t region; + rdatasetheader_t *newheader; + + /* + * This routine does no node locking. See comments in + * 'load' below for more information on loading and + * locking. + */ + + + /* + * SOA records are only allowed at top of zone. + */ + if (rdataset->type == dns_rdatatype_soa && + !IS_CACHE(rbtdb) && !dns_name_equal(name, &rbtdb->common.origin)) + return (DNS_R_NOTZONETOP); + + add_empty_wildcards(rbtdb, name); + + if (dns_name_iswildcard(name)) { + /* + * NS record owners cannot legally be wild cards. + */ + if (rdataset->type == dns_rdatatype_ns) + return (DNS_R_INVALIDNS); + result = add_wildcard_magic(rbtdb, name); + if (result != ISC_R_SUCCESS) + return (result); + } + + node = NULL; + result = dns_rbt_addnode(rbtdb->tree, name, &node); + if (result != ISC_R_SUCCESS && result != ISC_R_EXISTS) + return (result); + if (result != ISC_R_EXISTS) { + dns_name_t foundname; + dns_name_init(&foundname, NULL); + dns_rbt_namefromnode(node, &foundname); +#ifdef DNS_RBT_USEHASH + node->locknum = node->hashval % rbtdb->node_lock_count; +#else + node->locknum = dns_name_hash(&foundname, ISC_TRUE) % + rbtdb->node_lock_count; +#endif + } + + result = dns_rdataslab_fromrdataset(rdataset, rbtdb->common.mctx, + ®ion, + sizeof(rdatasetheader_t)); + if (result != ISC_R_SUCCESS) + return (result); + newheader = (rdatasetheader_t *)region.base; + newheader->ttl = rdataset->ttl + loadctx->now; /* XXX overflow check */ + newheader->type = RBTDB_RDATATYPE_VALUE(rdataset->type, + rdataset->covers); + newheader->attributes = 0; + newheader->trust = rdataset->trust; + newheader->serial = 1; + newheader->noqname = NULL; + newheader->count = init_count++; + newheader->additional_auth = NULL; + newheader->additional_glue = NULL; + + result = add(rbtdb, node, rbtdb->current_version, newheader, + DNS_DBADD_MERGE, ISC_TRUE, NULL, 0); + if (result == ISC_R_SUCCESS && + delegating_type(rbtdb, node, rdataset->type)) + node->find_callback = 1; + else if (result == DNS_R_UNCHANGED) + result = ISC_R_SUCCESS; + + return (result); +} + +static isc_result_t +beginload(dns_db_t *db, dns_addrdatasetfunc_t *addp, dns_dbload_t **dbloadp) { + rbtdb_load_t *loadctx; + dns_rbtdb_t *rbtdb; + + rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + + loadctx = isc_mem_get(rbtdb->common.mctx, sizeof(*loadctx)); + if (loadctx == NULL) + return (ISC_R_NOMEMORY); + + loadctx->rbtdb = rbtdb; + if (IS_CACHE(rbtdb)) + isc_stdtime_get(&loadctx->now); + else + loadctx->now = 0; + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + + REQUIRE((rbtdb->attributes & (RBTDB_ATTR_LOADED|RBTDB_ATTR_LOADING)) + == 0); + rbtdb->attributes |= RBTDB_ATTR_LOADING; + + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + + *addp = loading_addrdataset; + *dbloadp = loadctx; + + return (ISC_R_SUCCESS); +} + +static isc_result_t +endload(dns_db_t *db, dns_dbload_t **dbloadp) { + rbtdb_load_t *loadctx; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(dbloadp != NULL); + loadctx = *dbloadp; + REQUIRE(loadctx->rbtdb == rbtdb); + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + + REQUIRE((rbtdb->attributes & RBTDB_ATTR_LOADING) != 0); + REQUIRE((rbtdb->attributes & RBTDB_ATTR_LOADED) == 0); + + rbtdb->attributes &= ~RBTDB_ATTR_LOADING; + rbtdb->attributes |= RBTDB_ATTR_LOADED; + + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); + + /* + * If there's a KEY rdataset at the zone origin containing a + * zone key, we consider the zone secure. + */ + if (! IS_CACHE(rbtdb)) + rbtdb->secure = iszonesecure(db, rbtdb->origin_node); + + *dbloadp = NULL; + + isc_mem_put(rbtdb->common.mctx, loadctx, sizeof(*loadctx)); + + return (ISC_R_SUCCESS); +} + +static isc_result_t +dump(dns_db_t *db, dns_dbversion_t *version, const char *filename, + dns_masterformat_t masterformat) { + dns_rbtdb_t *rbtdb; + + rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + + return (dns_master_dump2(rbtdb->common.mctx, db, version, + &dns_master_style_default, + filename, masterformat)); +} + +static void +delete_callback(void *data, void *arg) { + dns_rbtdb_t *rbtdb = arg; + rdatasetheader_t *current, *next; + + for (current = data; current != NULL; current = next) { + next = current->next; + free_rdataset(rbtdb->common.mctx, current); + } +} + +static isc_boolean_t +issecure(dns_db_t *db) { + dns_rbtdb_t *rbtdb; + isc_boolean_t secure; + + rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + secure = rbtdb->secure; + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + + return (secure); +} + +static unsigned int +nodecount(dns_db_t *db) { + dns_rbtdb_t *rbtdb; + unsigned int count; + + rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + count = dns_rbt_nodecount(rbtdb->tree); + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + + return (count); +} + +static void +settask(dns_db_t *db, isc_task_t *task) { + dns_rbtdb_t *rbtdb; + + rbtdb = (dns_rbtdb_t *)db; + + REQUIRE(VALID_RBTDB(rbtdb)); + + RBTDB_LOCK(&rbtdb->lock, isc_rwlocktype_write); + if (rbtdb->task != NULL) + isc_task_detach(&rbtdb->task); + if (task != NULL) + isc_task_attach(task, &rbtdb->task); + RBTDB_UNLOCK(&rbtdb->lock, isc_rwlocktype_write); +} + +static isc_boolean_t +ispersistent(dns_db_t *db) { + UNUSED(db); + return (ISC_FALSE); +} + +static isc_result_t +getoriginnode(dns_db_t *db, dns_dbnode_t **nodep) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)db; + dns_rbtnode_t *onode; + isc_result_t result = ISC_R_SUCCESS; + + REQUIRE(VALID_RBTDB(rbtdb)); + REQUIRE(nodep != NULL && *nodep == NULL); + + /* Note that the access to origin_node doesn't require a DB lock */ + onode = (dns_rbtnode_t *)rbtdb->origin_node; + if (onode != NULL) { + NODE_STRONGLOCK(&rbtdb->node_locks[onode->locknum].lock); + new_reference(rbtdb, onode); + NODE_STRONGUNLOCK(&rbtdb->node_locks[onode->locknum].lock); + + *nodep = rbtdb->origin_node; + } else { + INSIST(!IS_CACHE(rbtdb)); + result = ISC_R_NOTFOUND; + } + + return (result); +} + +static dns_dbmethods_t zone_methods = { + attach, + detach, + beginload, + endload, + dump, + currentversion, + newversion, + attachversion, + closeversion, + findnode, + zone_find, + zone_findzonecut, + attachnode, + detachnode, + expirenode, + printnode, + createiterator, + zone_findrdataset, + allrdatasets, + addrdataset, + subtractrdataset, + deleterdataset, + issecure, + nodecount, + ispersistent, + overmem, + settask, + getoriginnode +}; + +static dns_dbmethods_t cache_methods = { + attach, + detach, + beginload, + endload, + dump, + currentversion, + newversion, + attachversion, + closeversion, + findnode, + cache_find, + cache_findzonecut, + attachnode, + detachnode, + expirenode, + printnode, + createiterator, + cache_findrdataset, + allrdatasets, + addrdataset, + subtractrdataset, + deleterdataset, + issecure, + nodecount, + ispersistent, + overmem, + settask, + getoriginnode +}; + +isc_result_t +#ifdef DNS_RBTDB_VERSION64 +dns_rbtdb64_create +#else +dns_rbtdb_create +#endif + (isc_mem_t *mctx, dns_name_t *origin, dns_dbtype_t type, + dns_rdataclass_t rdclass, unsigned int argc, char *argv[], + void *driverarg, dns_db_t **dbp) +{ + dns_rbtdb_t *rbtdb; + isc_result_t result; + int i; + dns_name_t name; + + /* Keep the compiler happy. */ + UNUSED(argc); + UNUSED(argv); + UNUSED(driverarg); + + rbtdb = isc_mem_get(mctx, sizeof(*rbtdb)); + if (rbtdb == NULL) + return (ISC_R_NOMEMORY); + + memset(rbtdb, '\0', sizeof(*rbtdb)); + dns_name_init(&rbtdb->common.origin, NULL); + rbtdb->common.attributes = 0; + if (type == dns_dbtype_cache) { + rbtdb->common.methods = &cache_methods; + rbtdb->common.attributes |= DNS_DBATTR_CACHE; + } else if (type == dns_dbtype_stub) { + rbtdb->common.methods = &zone_methods; + rbtdb->common.attributes |= DNS_DBATTR_STUB; + } else + rbtdb->common.methods = &zone_methods; + rbtdb->common.rdclass = rdclass; + rbtdb->common.mctx = NULL; + + result = RBTDB_INITLOCK(&rbtdb->lock); + if (result != ISC_R_SUCCESS) + goto cleanup_rbtdb; + + result = isc_rwlock_init(&rbtdb->tree_lock, 0, 0); + if (result != ISC_R_SUCCESS) + goto cleanup_lock; + + if (rbtdb->node_lock_count == 0) { + if (IS_CACHE(rbtdb)) + rbtdb->node_lock_count = DEFAULT_CACHE_NODE_LOCK_COUNT; + else + rbtdb->node_lock_count = DEFAULT_NODE_LOCK_COUNT; + } + INSIST(rbtdb->node_lock_count < (1 << DNS_RBT_LOCKLENGTH)); + rbtdb->node_locks = isc_mem_get(mctx, rbtdb->node_lock_count * + sizeof(rbtdb_nodelock_t)); + if (rbtdb->node_locks == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup_tree_lock; + } + + rbtdb->active = rbtdb->node_lock_count; + + for (i = 0; i < (int)(rbtdb->node_lock_count); i++) { + result = NODE_INITLOCK(&rbtdb->node_locks[i].lock); + if (result == ISC_R_SUCCESS) { + result = isc_refcount_init(&rbtdb->node_locks[i].references, 0); + if (result != ISC_R_SUCCESS) + NODE_DESTROYLOCK(&rbtdb->node_locks[i].lock); + } + if (result != ISC_R_SUCCESS) { + while (i-- > 0) { + NODE_DESTROYLOCK(&rbtdb->node_locks[i].lock); + isc_refcount_decrement(&rbtdb->node_locks[i].references, NULL); + isc_refcount_destroy(&rbtdb->node_locks[i].references); + } + goto cleanup_node_locks; + } + rbtdb->node_locks[i].exiting = ISC_FALSE; + } + + /* + * Attach to the mctx. The database will persist so long as there + * are references to it, and attaching to the mctx ensures that our + * mctx won't disappear out from under us. + */ + isc_mem_attach(mctx, &rbtdb->common.mctx); + + /* + * Must be initalized before free_rbtdb() is called. + */ + isc_ondestroy_init(&rbtdb->common.ondest); + + /* + * Make a copy of the origin name. + */ + result = dns_name_dupwithoffsets(origin, mctx, &rbtdb->common.origin); + if (result != ISC_R_SUCCESS) { + free_rbtdb(rbtdb, ISC_FALSE, NULL); + return (result); + } + + /* + * Make the Red-Black Tree. + */ + result = dns_rbt_create(mctx, delete_callback, rbtdb, &rbtdb->tree); + if (result != ISC_R_SUCCESS) { + free_rbtdb(rbtdb, ISC_FALSE, NULL); + return (result); + } + /* + * In order to set the node callback bit correctly in zone databases, + * we need to know if the node has the origin name of the zone. + * In loading_addrdataset() we could simply compare the new name + * to the origin name, but this is expensive. Also, we don't know the + * node name in addrdataset(), so we need another way of knowing the + * zone's top. + * + * We now explicitly create a node for the zone's origin, and then + * we simply remember the node's address. This is safe, because + * the top-of-zone node can never be deleted, nor can its address + * change. + */ + if (!IS_CACHE(rbtdb)) { + rbtdb->origin_node = NULL; + result = dns_rbt_addnode(rbtdb->tree, &rbtdb->common.origin, + &rbtdb->origin_node); + if (result != ISC_R_SUCCESS) { + INSIST(result != ISC_R_EXISTS); + free_rbtdb(rbtdb, ISC_FALSE, NULL); + return (result); + } + /* + * We need to give the origin node the right locknum. + */ + dns_name_init(&name, NULL); + dns_rbt_namefromnode(rbtdb->origin_node, &name); +#ifdef DNS_RBT_USEHASH + rbtdb->origin_node->locknum = + rbtdb->origin_node->hashval % + rbtdb->node_lock_count; +#else + rbtdb->origin_node->locknum = + dns_name_hash(&name, ISC_TRUE) % + rbtdb->node_lock_count; +#endif + } + + /* + * Misc. Initialization. + */ + result = isc_refcount_init(&rbtdb->references, 1); + if (result != ISC_R_SUCCESS) { + free_rbtdb(rbtdb, ISC_FALSE, NULL); + return (result); + } + rbtdb->attributes = 0; + rbtdb->secure = ISC_FALSE; + rbtdb->overmem = ISC_FALSE; + rbtdb->task = NULL; + + /* + * Version Initialization. + */ + rbtdb->current_serial = 1; + rbtdb->least_serial = 1; + rbtdb->next_serial = 2; + rbtdb->current_version = allocate_version(mctx, 1, 1, ISC_FALSE); + if (rbtdb->current_version == NULL) { + isc_refcount_decrement(&rbtdb->references, NULL); + isc_refcount_destroy(&rbtdb->references); + free_rbtdb(rbtdb, ISC_FALSE, NULL); + return (ISC_R_NOMEMORY); + } + rbtdb->future_version = NULL; + ISC_LIST_INIT(rbtdb->open_versions); + /* + * Keep the current version in the open list so that list operation + * won't happen in normal lookup operations. + */ + PREPEND(rbtdb->open_versions, rbtdb->current_version, link); + + rbtdb->common.magic = DNS_DB_MAGIC; + rbtdb->common.impmagic = RBTDB_MAGIC; + + *dbp = (dns_db_t *)rbtdb; + + return (ISC_R_SUCCESS); + + cleanup_node_locks: + isc_mem_put(mctx, rbtdb->node_locks, + rbtdb->node_lock_count * sizeof(rbtdb_nodelock_t)); + + cleanup_tree_lock: + isc_rwlock_destroy(&rbtdb->tree_lock); + + cleanup_lock: + RBTDB_DESTROYLOCK(&rbtdb->lock); + + cleanup_rbtdb: + isc_mem_put(mctx, rbtdb, sizeof(*rbtdb)); + return (result); +} + + +/* + * Slabbed Rdataset Methods + */ + +static void +rdataset_disassociate(dns_rdataset_t *rdataset) { + dns_db_t *db = rdataset->private1; + dns_dbnode_t *node = rdataset->private2; + + detachnode(db, &node); +} + +static isc_result_t +rdataset_first(dns_rdataset_t *rdataset) { + unsigned char *raw = rdataset->private3; /* RDATASLAB */ + unsigned int count; + + count = raw[0] * 256 + raw[1]; + if (count == 0) { + rdataset->private5 = NULL; + return (ISC_R_NOMORE); + } + +#if DNS_RDATASET_FIXED + if ((rdataset->attributes & DNS_RDATASETATTR_LOADORDER) == 0) + raw += 2 + (4 * count); + else +#endif + raw += 2; + + /* + * The privateuint4 field is the number of rdata beyond the + * cursor position, so we decrement the total count by one + * before storing it. + * + * If DNS_RDATASETATTR_LOADORDER is not set 'raw' points to the + * first record. If DNS_RDATASETATTR_LOADORDER is set 'raw' points + * to the first entry in the offset table. + */ + count--; + rdataset->privateuint4 = count; + rdataset->private5 = raw; + + return (ISC_R_SUCCESS); +} + +static isc_result_t +rdataset_next(dns_rdataset_t *rdataset) { + unsigned int count; + unsigned int length; + unsigned char *raw; /* RDATASLAB */ + + count = rdataset->privateuint4; + if (count == 0) + return (ISC_R_NOMORE); + count--; + rdataset->privateuint4 = count; + + /* + * Skip forward one record (length + 4) or one offset (4). + */ + raw = rdataset->private5; +#if DNS_RDATASET_FIXED + if ((rdataset->attributes & DNS_RDATASETATTR_LOADORDER) == 0) { +#endif + length = raw[0] * 256 + raw[1]; + raw += length; +#if DNS_RDATASET_FIXED + } + rdataset->private5 = raw + 4; /* length(2) + order(2) */ +#else + rdataset->private5 = raw + 2; /* length(2) */ +#endif + + return (ISC_R_SUCCESS); +} + +static void +rdataset_current(dns_rdataset_t *rdataset, dns_rdata_t *rdata) { + unsigned char *raw = rdataset->private5; /* RDATASLAB */ +#if DNS_RDATASET_FIXED + unsigned int offset; +#endif + isc_region_t r; + + REQUIRE(raw != NULL); + + /* + * Find the start of the record if not already in private5 + * then skip the length and order fields. + */ +#if DNS_RDATASET_FIXED + if ((rdataset->attributes & DNS_RDATASETATTR_LOADORDER) != 0) { + offset = (raw[0] << 24) + (raw[1] << 16) + + (raw[2] << 8) + raw[3]; + raw = rdataset->private3; + raw += offset; + } +#endif + r.length = raw[0] * 256 + raw[1]; + +#if DNS_RDATASET_FIXED + raw += 4; +#else + raw += 2; +#endif + r.base = raw; + dns_rdata_fromregion(rdata, rdataset->rdclass, rdataset->type, &r); +} + +static void +rdataset_clone(dns_rdataset_t *source, dns_rdataset_t *target) { + dns_db_t *db = source->private1; + dns_dbnode_t *node = source->private2; + dns_dbnode_t *cloned_node = NULL; + + attachnode(db, node, &cloned_node); + *target = *source; + + /* + * Reset iterator state. + */ + target->privateuint4 = 0; + target->private5 = NULL; +} + +static unsigned int +rdataset_count(dns_rdataset_t *rdataset) { + unsigned char *raw = rdataset->private3; /* RDATASLAB */ + unsigned int count; + + count = raw[0] * 256 + raw[1]; + + return (count); +} + +static isc_result_t +rdataset_getnoqname(dns_rdataset_t *rdataset, dns_name_t *name, + dns_rdataset_t *nsec, dns_rdataset_t *nsecsig) +{ + dns_db_t *db = rdataset->private1; + dns_dbnode_t *node = rdataset->private2; + dns_dbnode_t *cloned_node; + struct noqname *noqname = rdataset->private6; + + cloned_node = NULL; + attachnode(db, node, &cloned_node); + nsec->methods = &rdataset_methods; + nsec->rdclass = db->rdclass; + nsec->type = dns_rdatatype_nsec; + nsec->covers = 0; + nsec->ttl = rdataset->ttl; + nsec->trust = rdataset->trust; + nsec->private1 = rdataset->private1; + nsec->private2 = rdataset->private2; + nsec->private3 = noqname->nsec; + nsec->privateuint4 = 0; + nsec->private5 = NULL; + nsec->private6 = NULL; + + cloned_node = NULL; + attachnode(db, node, &cloned_node); + nsecsig->methods = &rdataset_methods; + nsecsig->rdclass = db->rdclass; + nsecsig->type = dns_rdatatype_rrsig; + nsecsig->covers = dns_rdatatype_nsec; + nsecsig->ttl = rdataset->ttl; + nsecsig->trust = rdataset->trust; + nsecsig->private1 = rdataset->private1; + nsecsig->private2 = rdataset->private2; + nsecsig->private3 = noqname->nsecsig; + nsecsig->privateuint4 = 0; + nsecsig->private5 = NULL; + nsec->private6 = NULL; + + dns_name_clone(&noqname->name, name); + + return (ISC_R_SUCCESS); +} + +/* + * Rdataset Iterator Methods + */ + +static void +rdatasetiter_destroy(dns_rdatasetiter_t **iteratorp) { + rbtdb_rdatasetiter_t *rbtiterator; + + rbtiterator = (rbtdb_rdatasetiter_t *)(*iteratorp); + + if (rbtiterator->common.version != NULL) + closeversion(rbtiterator->common.db, + &rbtiterator->common.version, ISC_FALSE); + detachnode(rbtiterator->common.db, &rbtiterator->common.node); + isc_mem_put(rbtiterator->common.db->mctx, rbtiterator, + sizeof(*rbtiterator)); + + *iteratorp = NULL; +} + +static isc_result_t +rdatasetiter_first(dns_rdatasetiter_t *iterator) { + rbtdb_rdatasetiter_t *rbtiterator = (rbtdb_rdatasetiter_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)(rbtiterator->common.db); + dns_rbtnode_t *rbtnode = rbtiterator->common.node; + rbtdb_version_t *rbtversion = rbtiterator->common.version; + rdatasetheader_t *header, *top_next; + rbtdb_serial_t serial; + isc_stdtime_t now; + + if (IS_CACHE(rbtdb)) { + serial = 1; + now = rbtiterator->common.now; + } else { + serial = rbtversion->serial; + now = 0; + } + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + for (header = rbtnode->data; header != NULL; header = top_next) { + top_next = header->next; + do { + if (header->serial <= serial && !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't exist" + * record? Or is it too old in the cache? + * + * Note: unlike everywhere else, we + * check for now > header->ttl instead + * of now >= header->ttl. This allows + * ANY and RRSIG queries for 0 TTL + * rdatasets to work. + */ + if (NONEXISTENT(header) || + (now != 0 && now > header->ttl)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) + break; + } + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + rbtiterator->current = header; + + if (header == NULL) + return (ISC_R_NOMORE); + + return (ISC_R_SUCCESS); +} + +static isc_result_t +rdatasetiter_next(dns_rdatasetiter_t *iterator) { + rbtdb_rdatasetiter_t *rbtiterator = (rbtdb_rdatasetiter_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)(rbtiterator->common.db); + dns_rbtnode_t *rbtnode = rbtiterator->common.node; + rbtdb_version_t *rbtversion = rbtiterator->common.version; + rdatasetheader_t *header, *top_next; + rbtdb_serial_t serial; + isc_stdtime_t now; + rbtdb_rdatatype_t type, negtype; + dns_rdatatype_t rdtype, covers; + + header = rbtiterator->current; + if (header == NULL) + return (ISC_R_NOMORE); + + if (IS_CACHE(rbtdb)) { + serial = 1; + now = rbtiterator->common.now; + } else { + serial = rbtversion->serial; + now = 0; + } + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + type = header->type; + rdtype = RBTDB_RDATATYPE_BASE(header->type); + if (rdtype == 0) { + covers = RBTDB_RDATATYPE_EXT(header->type); + negtype = RBTDB_RDATATYPE_VALUE(covers, 0); + } else + negtype = RBTDB_RDATATYPE_VALUE(0, rdtype); + for (header = header->next; header != NULL; header = top_next) { + top_next = header->next; + /* + * If not walking back up the down list. + */ + if (header->type != type && header->type != negtype) { + do { + if (header->serial <= serial && + !IGNORE(header)) { + /* + * Is this a "this rdataset doesn't + * exist" record? + * + * Note: unlike everywhere else, we + * check for now > header->ttl instead + * of now >= header->ttl. This allows + * ANY and RRSIG queries for 0 TTL + * rdatasets to work. + */ + if ((header->attributes & + RDATASET_ATTR_NONEXISTENT) != 0 || + (now != 0 && now > header->ttl)) + header = NULL; + break; + } else + header = header->down; + } while (header != NULL); + if (header != NULL) + break; + } + } + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + rbtiterator->current = header; + + if (header == NULL) + return (ISC_R_NOMORE); + + return (ISC_R_SUCCESS); +} + +static void +rdatasetiter_current(dns_rdatasetiter_t *iterator, dns_rdataset_t *rdataset) { + rbtdb_rdatasetiter_t *rbtiterator = (rbtdb_rdatasetiter_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)(rbtiterator->common.db); + dns_rbtnode_t *rbtnode = rbtiterator->common.node; + rdatasetheader_t *header; + + header = rbtiterator->current; + REQUIRE(header != NULL); + + NODE_LOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); + + bind_rdataset(rbtdb, rbtnode, header, rbtiterator->common.now, + rdataset); + + NODE_UNLOCK(&rbtdb->node_locks[rbtnode->locknum].lock, + isc_rwlocktype_read); +} + + +/* + * Database Iterator Methods + */ + +static inline void +reference_iter_node(rbtdb_dbiterator_t *rbtdbiter) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db; + dns_rbtnode_t *node = rbtdbiter->node; + + if (node == NULL) + return; + + INSIST(rbtdbiter->tree_locked != isc_rwlocktype_none); + NODE_STRONGLOCK(&rbtdb->node_locks[node->locknum].lock); + new_reference(rbtdb, node); + NODE_STRONGUNLOCK(&rbtdb->node_locks[node->locknum].lock); +} + +static inline void +dereference_iter_node(rbtdb_dbiterator_t *rbtdbiter) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db; + dns_rbtnode_t *node = rbtdbiter->node; + nodelock_t *lock; + + if (node == NULL) + return; + + lock = &rbtdb->node_locks[node->locknum].lock; + NODE_LOCK(lock, isc_rwlocktype_read); + decrement_reference(rbtdb, node, 0, isc_rwlocktype_read, + rbtdbiter->tree_locked); + NODE_UNLOCK(lock, isc_rwlocktype_read); + + rbtdbiter->node = NULL; +} + +static void +flush_deletions(rbtdb_dbiterator_t *rbtdbiter) { + dns_rbtnode_t *node; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db; + isc_boolean_t was_read_locked = ISC_FALSE; + nodelock_t *lock; + int i; + + if (rbtdbiter->delete != 0) { + /* + * Note that "%d node of %d in tree" can report things like + * "flush_deletions: 59 nodes of 41 in tree". This means + * That some nodes appear on the deletions list more than + * once. Only the last occurence will actually be deleted. + */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_CACHE, ISC_LOG_DEBUG(1), + "flush_deletions: %d nodes of %d in tree", + rbtdbiter->delete, + dns_rbt_nodecount(rbtdb->tree)); + + if (rbtdbiter->tree_locked == isc_rwlocktype_read) { + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + was_read_locked = ISC_TRUE; + } + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_write); + rbtdbiter->tree_locked = isc_rwlocktype_write; + + for (i = 0; i < rbtdbiter->delete; i++) { + node = rbtdbiter->deletions[i]; + lock = &rbtdb->node_locks[node->locknum].lock; + + NODE_LOCK(lock, isc_rwlocktype_read); + decrement_reference(rbtdb, node, 0, + isc_rwlocktype_read, + rbtdbiter->tree_locked); + NODE_UNLOCK(lock, isc_rwlocktype_read); + } + + rbtdbiter->delete = 0; + + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_write); + if (was_read_locked) { + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + rbtdbiter->tree_locked = isc_rwlocktype_read; + + } else { + rbtdbiter->tree_locked = isc_rwlocktype_none; + } + } +} + +static inline void +resume_iteration(rbtdb_dbiterator_t *rbtdbiter) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db; + + REQUIRE(rbtdbiter->paused); + REQUIRE(rbtdbiter->tree_locked == isc_rwlocktype_none); + + RWLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + rbtdbiter->tree_locked = isc_rwlocktype_read; + + rbtdbiter->paused = ISC_FALSE; +} + +static void +dbiterator_destroy(dns_dbiterator_t **iteratorp) { + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)(*iteratorp); + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)rbtdbiter->common.db; + dns_db_t *db = NULL; + + if (rbtdbiter->tree_locked == isc_rwlocktype_read) { + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + rbtdbiter->tree_locked = isc_rwlocktype_none; + } else + INSIST(rbtdbiter->tree_locked == isc_rwlocktype_none); + + dereference_iter_node(rbtdbiter); + + flush_deletions(rbtdbiter); + + dns_db_attach(rbtdbiter->common.db, &db); + dns_db_detach(&rbtdbiter->common.db); + + dns_rbtnodechain_reset(&rbtdbiter->chain); + isc_mem_put(db->mctx, rbtdbiter, sizeof(*rbtdbiter)); + dns_db_detach(&db); + + *iteratorp = NULL; +} + +static isc_result_t +dbiterator_first(dns_dbiterator_t *iterator) { + isc_result_t result; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)iterator->db; + dns_name_t *name, *origin; + + if (rbtdbiter->result != ISC_R_SUCCESS && + rbtdbiter->result != ISC_R_NOMORE) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + dereference_iter_node(rbtdbiter); + + name = dns_fixedname_name(&rbtdbiter->name); + origin = dns_fixedname_name(&rbtdbiter->origin); + dns_rbtnodechain_reset(&rbtdbiter->chain); + + result = dns_rbtnodechain_first(&rbtdbiter->chain, rbtdb->tree, name, + origin); + + if (result == ISC_R_SUCCESS || result == DNS_R_NEWORIGIN) { + result = dns_rbtnodechain_current(&rbtdbiter->chain, NULL, + NULL, &rbtdbiter->node); + if (result == ISC_R_SUCCESS) { + rbtdbiter->new_origin = ISC_TRUE; + reference_iter_node(rbtdbiter); + } + } else { + INSIST(result == ISC_R_NOTFOUND); + result = ISC_R_NOMORE; /* The tree is empty. */ + } + + rbtdbiter->result = result; + + return (result); +} + +static isc_result_t +dbiterator_last(dns_dbiterator_t *iterator) { + isc_result_t result; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)iterator->db; + dns_name_t *name, *origin; + + if (rbtdbiter->result != ISC_R_SUCCESS && + rbtdbiter->result != ISC_R_NOMORE) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + dereference_iter_node(rbtdbiter); + + name = dns_fixedname_name(&rbtdbiter->name); + origin = dns_fixedname_name(&rbtdbiter->origin); + dns_rbtnodechain_reset(&rbtdbiter->chain); + + result = dns_rbtnodechain_last(&rbtdbiter->chain, rbtdb->tree, name, + origin); + if (result == ISC_R_SUCCESS || result == DNS_R_NEWORIGIN) { + result = dns_rbtnodechain_current(&rbtdbiter->chain, NULL, + NULL, &rbtdbiter->node); + if (result == ISC_R_SUCCESS) { + rbtdbiter->new_origin = ISC_TRUE; + reference_iter_node(rbtdbiter); + } + } else { + INSIST(result == ISC_R_NOTFOUND); + result = ISC_R_NOMORE; /* The tree is empty. */ + } + + rbtdbiter->result = result; + + return (result); +} + +static isc_result_t +dbiterator_seek(dns_dbiterator_t *iterator, dns_name_t *name) { + isc_result_t result; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)iterator->db; + dns_name_t *iname, *origin; + + if (rbtdbiter->result != ISC_R_SUCCESS && + rbtdbiter->result != ISC_R_NOMORE) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + dereference_iter_node(rbtdbiter); + + iname = dns_fixedname_name(&rbtdbiter->name); + origin = dns_fixedname_name(&rbtdbiter->origin); + dns_rbtnodechain_reset(&rbtdbiter->chain); + + result = dns_rbt_findnode(rbtdb->tree, name, NULL, &rbtdbiter->node, + &rbtdbiter->chain, DNS_RBTFIND_EMPTYDATA, + NULL, NULL); + if (result == ISC_R_SUCCESS) { + result = dns_rbtnodechain_current(&rbtdbiter->chain, iname, + origin, NULL); + if (result == ISC_R_SUCCESS) { + rbtdbiter->new_origin = ISC_TRUE; + reference_iter_node(rbtdbiter); + } + + } else if (result == DNS_R_PARTIALMATCH) + result = ISC_R_NOTFOUND; + + rbtdbiter->result = result; + + return (result); +} + +static isc_result_t +dbiterator_prev(dns_dbiterator_t *iterator) { + isc_result_t result; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_name_t *name, *origin; + + REQUIRE(rbtdbiter->node != NULL); + + if (rbtdbiter->result != ISC_R_SUCCESS) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + name = dns_fixedname_name(&rbtdbiter->name); + origin = dns_fixedname_name(&rbtdbiter->origin); + result = dns_rbtnodechain_prev(&rbtdbiter->chain, name, origin); + + dereference_iter_node(rbtdbiter); + + if (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) { + rbtdbiter->new_origin = ISC_TF(result == DNS_R_NEWORIGIN); + result = dns_rbtnodechain_current(&rbtdbiter->chain, NULL, + NULL, &rbtdbiter->node); + } + + if (result == ISC_R_SUCCESS) + reference_iter_node(rbtdbiter); + + rbtdbiter->result = result; + + return (result); +} + +static isc_result_t +dbiterator_next(dns_dbiterator_t *iterator) { + isc_result_t result; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_name_t *name, *origin; + + REQUIRE(rbtdbiter->node != NULL); + + if (rbtdbiter->result != ISC_R_SUCCESS) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + name = dns_fixedname_name(&rbtdbiter->name); + origin = dns_fixedname_name(&rbtdbiter->origin); + result = dns_rbtnodechain_next(&rbtdbiter->chain, name, origin); + + dereference_iter_node(rbtdbiter); + + if (result == DNS_R_NEWORIGIN || result == ISC_R_SUCCESS) { + rbtdbiter->new_origin = ISC_TF(result == DNS_R_NEWORIGIN); + result = dns_rbtnodechain_current(&rbtdbiter->chain, NULL, + NULL, &rbtdbiter->node); + } + if (result == ISC_R_SUCCESS) + reference_iter_node(rbtdbiter); + + rbtdbiter->result = result; + + return (result); +} + +static isc_result_t +dbiterator_current(dns_dbiterator_t *iterator, dns_dbnode_t **nodep, + dns_name_t *name) +{ + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)iterator->db; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_rbtnode_t *node = rbtdbiter->node; + isc_result_t result; + dns_name_t *nodename = dns_fixedname_name(&rbtdbiter->name); + dns_name_t *origin = dns_fixedname_name(&rbtdbiter->origin); + + REQUIRE(rbtdbiter->result == ISC_R_SUCCESS); + REQUIRE(rbtdbiter->node != NULL); + + if (rbtdbiter->paused) + resume_iteration(rbtdbiter); + + if (name != NULL) { + if (rbtdbiter->common.relative_names) + origin = NULL; + result = dns_name_concatenate(nodename, origin, name, NULL); + if (result != ISC_R_SUCCESS) + return (result); + if (rbtdbiter->common.relative_names && rbtdbiter->new_origin) + result = DNS_R_NEWORIGIN; + } else + result = ISC_R_SUCCESS; + + NODE_STRONGLOCK(&rbtdb->node_locks[node->locknum].lock); + new_reference(rbtdb, node); + NODE_STRONGUNLOCK(&rbtdb->node_locks[node->locknum].lock); + + *nodep = rbtdbiter->node; + + if (iterator->cleaning && result == ISC_R_SUCCESS) { + isc_result_t expire_result; + + /* + * If the deletion array is full, flush it before trying + * to expire the current node. The current node can't + * fully deleted while the iteration cursor is still on it. + */ + if (rbtdbiter->delete == DELETION_BATCH_MAX) + flush_deletions(rbtdbiter); + + expire_result = expirenode(iterator->db, *nodep, 0); + + /* + * expirenode() currently always returns success. + */ + if (expire_result == ISC_R_SUCCESS && node->down == NULL) { + unsigned int refs; + + rbtdbiter->deletions[rbtdbiter->delete++] = node; + NODE_STRONGLOCK(&rbtdb->node_locks[node->locknum].lock); + dns_rbtnode_refincrement(node, &refs); + INSIST(refs != 0); + NODE_STRONGUNLOCK(&rbtdb->node_locks[node->locknum].lock); + } + } + + return (result); +} + +static isc_result_t +dbiterator_pause(dns_dbiterator_t *iterator) { + dns_rbtdb_t *rbtdb = (dns_rbtdb_t *)iterator->db; + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + + if (rbtdbiter->result != ISC_R_SUCCESS && + rbtdbiter->result != ISC_R_NOMORE) + return (rbtdbiter->result); + + if (rbtdbiter->paused) + return (ISC_R_SUCCESS); + + rbtdbiter->paused = ISC_TRUE; + + if (rbtdbiter->tree_locked != isc_rwlocktype_none) { + INSIST(rbtdbiter->tree_locked == isc_rwlocktype_read); + RWUNLOCK(&rbtdb->tree_lock, isc_rwlocktype_read); + rbtdbiter->tree_locked = isc_rwlocktype_none; + } + + flush_deletions(rbtdbiter); + + return (ISC_R_SUCCESS); +} + +static isc_result_t +dbiterator_origin(dns_dbiterator_t *iterator, dns_name_t *name) { + rbtdb_dbiterator_t *rbtdbiter = (rbtdb_dbiterator_t *)iterator; + dns_name_t *origin = dns_fixedname_name(&rbtdbiter->origin); + + if (rbtdbiter->result != ISC_R_SUCCESS) + return (rbtdbiter->result); + + return (dns_name_copy(origin, name, NULL)); +} + +/*% + * Additional cache routines. + */ +static isc_result_t +rdataset_getadditional(dns_rdataset_t *rdataset, dns_rdatasetadditional_t type, + dns_rdatatype_t qtype, dns_acache_t *acache, + dns_zone_t **zonep, dns_db_t **dbp, + dns_dbversion_t **versionp, dns_dbnode_t **nodep, + dns_name_t *fname, dns_message_t *msg, + isc_stdtime_t now) +{ + dns_rbtdb_t *rbtdb = rdataset->private1; + dns_rbtnode_t *rbtnode = rdataset->private2; + unsigned char *raw = rdataset->private3; /* RDATASLAB */ + unsigned int current_count = rdataset->privateuint4; + unsigned int count; + rdatasetheader_t *header; + nodelock_t *nodelock; + unsigned int total_count; + acachectl_t *acarray; + dns_acacheentry_t *entry; + isc_result_t result; + + UNUSED(qtype); /* we do not use this value at least for now */ + UNUSED(acache); + + header = (struct rdatasetheader *)(raw - sizeof(*header)); + + total_count = raw[0] * 256 + raw[1]; + INSIST(total_count > current_count); + count = total_count - current_count - 1; + + acarray = NULL; + + nodelock = &rbtdb->node_locks[rbtnode->locknum].lock; + NODE_LOCK(nodelock, isc_rwlocktype_read); + + switch (type) { + case dns_rdatasetadditional_fromauth: + acarray = header->additional_auth; + break; + case dns_rdatasetadditional_fromcache: + acarray = NULL; + break; + case dns_rdatasetadditional_fromglue: + acarray = header->additional_glue; + break; + default: + INSIST(0); + } + + if (acarray == NULL) { + if (type != dns_rdatasetadditional_fromcache) + dns_acache_countquerymiss(acache); + NODE_UNLOCK(nodelock, isc_rwlocktype_read); + return (ISC_R_NOTFOUND); + } + + if (acarray[count].entry == NULL) { + dns_acache_countquerymiss(acache); + NODE_UNLOCK(nodelock, isc_rwlocktype_read); + return (ISC_R_NOTFOUND); + } + + entry = NULL; + dns_acache_attachentry(acarray[count].entry, &entry); + + NODE_UNLOCK(nodelock, isc_rwlocktype_read); + + result = dns_acache_getentry(entry, zonep, dbp, versionp, + nodep, fname, msg, now); + + dns_acache_detachentry(&entry); + + return (result); +} + +static void +acache_callback(dns_acacheentry_t *entry, void **arg) { + dns_rbtdb_t *rbtdb; + dns_rbtnode_t *rbtnode; + nodelock_t *nodelock; + acachectl_t *acarray = NULL; + acache_cbarg_t *cbarg; + unsigned int count; + + REQUIRE(arg != NULL); + cbarg = *arg; + + /* + * The caller must hold the entry lock. + */ + + rbtdb = (dns_rbtdb_t *)cbarg->db; + rbtnode = (dns_rbtnode_t *)cbarg->node; + + nodelock = &rbtdb->node_locks[rbtnode->locknum].lock; + NODE_LOCK(nodelock, isc_rwlocktype_write); + + switch (cbarg->type) { + case dns_rdatasetadditional_fromauth: + acarray = cbarg->header->additional_auth; + break; + case dns_rdatasetadditional_fromglue: + acarray = cbarg->header->additional_glue; + break; + default: + INSIST(0); + } + + count = cbarg->count; + if (acarray[count].entry == entry) + acarray[count].entry = NULL; + INSIST(acarray[count].cbarg != NULL); + isc_mem_put(rbtdb->common.mctx, acarray[count].cbarg, + sizeof(acache_cbarg_t)); + acarray[count].cbarg = NULL; + + dns_acache_detachentry(&entry); + + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + + dns_db_detachnode((dns_db_t *)rbtdb, (dns_dbnode_t **)(void*)&rbtnode); + dns_db_detach((dns_db_t **)(void*)&rbtdb); + + *arg = NULL; +} + +static void +acache_cancelentry(isc_mem_t *mctx, dns_acacheentry_t *entry, + acache_cbarg_t **cbargp) +{ + acache_cbarg_t *cbarg; + + REQUIRE(mctx != NULL); + REQUIRE(entry != NULL); + REQUIRE(cbargp != NULL && *cbargp != NULL); + + cbarg = *cbargp; + + dns_acache_cancelentry(entry); + dns_db_detachnode(cbarg->db, &cbarg->node); + dns_db_detach(&cbarg->db); + + isc_mem_put(mctx, cbarg, sizeof(acache_cbarg_t)); + + *cbargp = NULL; +} + +static isc_result_t +rdataset_setadditional(dns_rdataset_t *rdataset, dns_rdatasetadditional_t type, + dns_rdatatype_t qtype, dns_acache_t *acache, + dns_zone_t *zone, dns_db_t *db, + dns_dbversion_t *version, dns_dbnode_t *node, + dns_name_t *fname) +{ + dns_rbtdb_t *rbtdb = rdataset->private1; + dns_rbtnode_t *rbtnode = rdataset->private2; + unsigned char *raw = rdataset->private3; /* RDATASLAB */ + unsigned int current_count = rdataset->privateuint4; + rdatasetheader_t *header; + unsigned int total_count, count; + nodelock_t *nodelock; + isc_result_t result; + acachectl_t *acarray; + dns_acacheentry_t *newentry, *oldentry = NULL; + acache_cbarg_t *newcbarg, *oldcbarg = NULL; + + UNUSED(qtype); + + if (type == dns_rdatasetadditional_fromcache) + return (ISC_R_SUCCESS); + + header = (struct rdatasetheader *)(raw - sizeof(*header)); + + total_count = raw[0] * 256 + raw[1]; + INSIST(total_count > current_count); + count = total_count - current_count - 1; /* should be private data */ + + newcbarg = isc_mem_get(rbtdb->common.mctx, sizeof(*newcbarg)); + if (newcbarg == NULL) + return (ISC_R_NOMEMORY); + newcbarg->type = type; + newcbarg->count = count; + newcbarg->header = header; + newcbarg->db = NULL; + dns_db_attach((dns_db_t *)rbtdb, &newcbarg->db); + newcbarg->node = NULL; + dns_db_attachnode((dns_db_t *)rbtdb, (dns_dbnode_t *)rbtnode, + &newcbarg->node); + newentry = NULL; + result = dns_acache_createentry(acache, (dns_db_t *)rbtdb, + acache_callback, newcbarg, &newentry); + if (result != ISC_R_SUCCESS) + goto fail; + /* Set cache data in the new entry. */ + result = dns_acache_setentry(acache, newentry, zone, db, + version, node, fname); + if (result != ISC_R_SUCCESS) + goto fail; + + nodelock = &rbtdb->node_locks[rbtnode->locknum].lock; + NODE_LOCK(nodelock, isc_rwlocktype_write); + + acarray = NULL; + switch (type) { + case dns_rdatasetadditional_fromauth: + acarray = header->additional_auth; + break; + case dns_rdatasetadditional_fromglue: + acarray = header->additional_glue; + break; + default: + INSIST(0); + } + + if (acarray == NULL) { + unsigned int i; + + acarray = isc_mem_get(rbtdb->common.mctx, total_count * + sizeof(acachectl_t)); + + if (acarray == NULL) { + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + goto fail; + } + + for (i = 0; i < total_count; i++) { + acarray[i].entry = NULL; + acarray[i].cbarg = NULL; + } + } + switch (type) { + case dns_rdatasetadditional_fromauth: + header->additional_auth = acarray; + break; + case dns_rdatasetadditional_fromglue: + header->additional_glue = acarray; + break; + default: + INSIST(0); + } + + if (acarray[count].entry != NULL) { + /* + * Swap the entry. Delay cleaning-up the old entry since + * it would require a node lock. + */ + oldentry = acarray[count].entry; + INSIST(acarray[count].cbarg != NULL); + oldcbarg = acarray[count].cbarg; + } + acarray[count].entry = newentry; + acarray[count].cbarg = newcbarg; + + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + + if (oldentry != NULL) { + if (oldcbarg != NULL) + acache_cancelentry(rbtdb->common.mctx, oldentry, + &oldcbarg); + dns_acache_detachentry(&oldentry); + } + + return (ISC_R_SUCCESS); + + fail: + if (newcbarg != NULL) { + if (newentry != NULL) { + acache_cancelentry(rbtdb->common.mctx, newentry, + &newcbarg); + dns_acache_detachentry(&newentry); + } else { + dns_db_detachnode((dns_db_t *)rbtdb, &newcbarg->node); + dns_db_detach(&newcbarg->db); + isc_mem_put(rbtdb->common.mctx, newcbarg, + sizeof(*newcbarg)); + } + } + + return (result); +} + +static isc_result_t +rdataset_putadditional(dns_acache_t *acache, dns_rdataset_t *rdataset, + dns_rdatasetadditional_t type, dns_rdatatype_t qtype) +{ + dns_rbtdb_t *rbtdb = rdataset->private1; + dns_rbtnode_t *rbtnode = rdataset->private2; + unsigned char *raw = rdataset->private3; /* RDATASLAB */ + unsigned int current_count = rdataset->privateuint4; + rdatasetheader_t *header; + nodelock_t *nodelock; + unsigned int total_count, count; + acachectl_t *acarray; + dns_acacheentry_t *entry; + acache_cbarg_t *cbarg; + + UNUSED(qtype); /* we do not use this value at least for now */ + UNUSED(acache); + + if (type == dns_rdatasetadditional_fromcache) + return (ISC_R_SUCCESS); + + header = (struct rdatasetheader *)(raw - sizeof(*header)); + + total_count = raw[0] * 256 + raw[1]; + INSIST(total_count > current_count); + count = total_count - current_count - 1; + + acarray = NULL; + entry = NULL; + + nodelock = &rbtdb->node_locks[rbtnode->locknum].lock; + NODE_LOCK(nodelock, isc_rwlocktype_write); + + switch (type) { + case dns_rdatasetadditional_fromauth: + acarray = header->additional_auth; + break; + case dns_rdatasetadditional_fromglue: + acarray = header->additional_glue; + break; + default: + INSIST(0); + } + + if (acarray == NULL) { + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + return (ISC_R_NOTFOUND); + } + + entry = acarray[count].entry; + if (entry == NULL) { + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + return (ISC_R_NOTFOUND); + } + + acarray[count].entry = NULL; + cbarg = acarray[count].cbarg; + acarray[count].cbarg = NULL; + + NODE_UNLOCK(nodelock, isc_rwlocktype_write); + + if (entry != NULL) { + if (cbarg != NULL) + acache_cancelentry(rbtdb->common.mctx, entry, &cbarg); + dns_acache_detachentry(&entry); + } + + return (ISC_R_SUCCESS); +} |
