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diff --git a/lib/dns/adb.c b/lib/dns/adb.c
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@@ -0,0 +1,4749 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+/*! \file
+ *
+ * \note
+ * In finds, if task == NULL, no events will be generated, and no events
+ * have been sent. If task != NULL but taskaction == NULL, an event has been
+ * posted but not yet freed. If neither are NULL, no event was posted.
+ *
+ */
+
+#include <inttypes.h>
+#include <limits.h>
+#include <stdbool.h>
+
+#include <isc/mutexblock.h>
+#include <isc/netaddr.h>
+#include <isc/print.h>
+#include <isc/random.h>
+#include <isc/result.h>
+#include <isc/stats.h>
+#include <isc/string.h> /* Required for HP/UX (and others?) */
+#include <isc/task.h>
+#include <isc/util.h>
+
+#include <dns/adb.h>
+#include <dns/db.h>
+#include <dns/events.h>
+#include <dns/log.h>
+#include <dns/rdata.h>
+#include <dns/rdataset.h>
+#include <dns/rdatastruct.h>
+#include <dns/rdatatype.h>
+#include <dns/resolver.h>
+#include <dns/stats.h>
+
+#define DNS_ADB_MAGIC ISC_MAGIC('D', 'a', 'd', 'b')
+#define DNS_ADB_VALID(x) ISC_MAGIC_VALID(x, DNS_ADB_MAGIC)
+#define DNS_ADBNAME_MAGIC ISC_MAGIC('a', 'd', 'b', 'N')
+#define DNS_ADBNAME_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAME_MAGIC)
+#define DNS_ADBNAMEHOOK_MAGIC ISC_MAGIC('a', 'd', 'N', 'H')
+#define DNS_ADBNAMEHOOK_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBNAMEHOOK_MAGIC)
+#define DNS_ADBLAMEINFO_MAGIC ISC_MAGIC('a', 'd', 'b', 'Z')
+#define DNS_ADBLAMEINFO_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBLAMEINFO_MAGIC)
+#define DNS_ADBENTRY_MAGIC ISC_MAGIC('a', 'd', 'b', 'E')
+#define DNS_ADBENTRY_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBENTRY_MAGIC)
+#define DNS_ADBFETCH_MAGIC ISC_MAGIC('a', 'd', 'F', '4')
+#define DNS_ADBFETCH_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH_MAGIC)
+#define DNS_ADBFETCH6_MAGIC ISC_MAGIC('a', 'd', 'F', '6')
+#define DNS_ADBFETCH6_VALID(x) ISC_MAGIC_VALID(x, DNS_ADBFETCH6_MAGIC)
+
+/*!
+ * For type 3 negative cache entries, we will remember that the address is
+ * broken for this long. XXXMLG This is also used for actual addresses, too.
+ * The intent is to keep us from constantly asking about A/AAAA records
+ * if the zone has extremely low TTLs.
+ */
+#define ADB_CACHE_MINIMUM 10 /*%< seconds */
+#define ADB_CACHE_MAXIMUM 86400 /*%< seconds (86400 = 24 hours) */
+#define ADB_ENTRY_WINDOW 1800 /*%< seconds */
+
+/*%
+ * The period in seconds after which an ADB name entry is regarded as stale
+ * and forced to be cleaned up.
+ * TODO: This should probably be configurable at run-time.
+ */
+#ifndef ADB_STALE_MARGIN
+#define ADB_STALE_MARGIN 1800
+#endif /* ifndef ADB_STALE_MARGIN */
+
+#define FREE_ITEMS 64 /*%< free count for memory pools */
+#define FILL_COUNT 16 /*%< fill count for memory pools */
+
+#define DNS_ADB_INVALIDBUCKET (-1) /*%< invalid bucket address */
+
+#define DNS_ADB_MINADBSIZE (1024U * 1024U) /*%< 1 Megabyte */
+
+typedef ISC_LIST(dns_adbname_t) dns_adbnamelist_t;
+typedef struct dns_adbnamehook dns_adbnamehook_t;
+typedef ISC_LIST(dns_adbnamehook_t) dns_adbnamehooklist_t;
+typedef struct dns_adblameinfo dns_adblameinfo_t;
+typedef ISC_LIST(dns_adbentry_t) dns_adbentrylist_t;
+typedef struct dns_adbfetch dns_adbfetch_t;
+typedef struct dns_adbfetch6 dns_adbfetch6_t;
+
+/*% dns adb structure */
+struct dns_adb {
+ unsigned int magic;
+
+ isc_mutex_t lock;
+ isc_mutex_t reflock; /*%< Covers irefcnt, erefcnt */
+ isc_mutex_t overmemlock; /*%< Covers overmem */
+ isc_mem_t *mctx;
+ isc_mem_t *hmctx;
+ dns_view_t *view;
+
+ isc_taskmgr_t *taskmgr;
+ isc_task_t *task;
+ isc_task_t *excl;
+
+ isc_interval_t tick_interval;
+ int next_cleanbucket;
+
+ unsigned int irefcnt;
+ unsigned int erefcnt;
+
+ isc_refcount_t ahrefcnt;
+ isc_refcount_t nhrefcnt;
+
+ /*!
+ * Bucketized locks and lists for names.
+ *
+ * XXXRTH Have a per-bucket structure that contains all of these?
+ */
+ unsigned int nnames;
+ isc_mutex_t namescntlock;
+ unsigned int namescnt;
+ dns_adbnamelist_t *names;
+ dns_adbnamelist_t *deadnames;
+ isc_mutex_t *namelocks;
+ bool *name_sd;
+ unsigned int *name_refcnt;
+
+ /*!
+ * Bucketized locks and lists for entries.
+ *
+ * XXXRTH Have a per-bucket structure that contains all of these?
+ */
+ unsigned int nentries;
+ isc_mutex_t entriescntlock;
+ unsigned int entriescnt;
+ dns_adbentrylist_t *entries;
+ dns_adbentrylist_t *deadentries;
+ isc_mutex_t *entrylocks;
+ bool *entry_sd; /*%< shutting down */
+ unsigned int *entry_refcnt;
+
+ isc_event_t cevent;
+ bool cevent_out;
+ atomic_bool shutting_down;
+ isc_eventlist_t whenshutdown;
+ isc_event_t growentries;
+ bool growentries_sent;
+ isc_event_t grownames;
+ bool grownames_sent;
+
+ uint32_t quota;
+ uint32_t atr_freq;
+ double atr_low;
+ double atr_high;
+ double atr_discount;
+};
+
+/*
+ * XXXMLG Document these structures.
+ */
+
+/*% dns_adbname structure */
+struct dns_adbname {
+ unsigned int magic;
+ dns_name_t name;
+ dns_adb_t *adb;
+ unsigned int partial_result;
+ unsigned int flags;
+ int lock_bucket;
+ dns_name_t target;
+ isc_stdtime_t expire_target;
+ isc_stdtime_t expire_v4;
+ isc_stdtime_t expire_v6;
+ unsigned int chains;
+ dns_adbnamehooklist_t v4;
+ dns_adbnamehooklist_t v6;
+ dns_adbfetch_t *fetch_a;
+ dns_adbfetch_t *fetch_aaaa;
+ unsigned int fetch_err;
+ unsigned int fetch6_err;
+ dns_adbfindlist_t finds;
+ /* for LRU-based management */
+ isc_stdtime_t last_used;
+
+ ISC_LINK(dns_adbname_t) plink;
+};
+
+/*% The adbfetch structure */
+struct dns_adbfetch {
+ unsigned int magic;
+ dns_fetch_t *fetch;
+ dns_rdataset_t rdataset;
+ unsigned int depth;
+};
+
+/*%
+ * This is a small widget that dangles off a dns_adbname_t. It contains a
+ * pointer to the address information about this host, and a link to the next
+ * namehook that will contain the next address this host has.
+ */
+struct dns_adbnamehook {
+ unsigned int magic;
+ dns_adbentry_t *entry;
+ ISC_LINK(dns_adbnamehook_t) plink;
+};
+
+/*%
+ * This is a small widget that holds qname-specific information about an
+ * address. Currently limited to lameness, but could just as easily be
+ * extended to other types of information about zones.
+ */
+struct dns_adblameinfo {
+ unsigned int magic;
+
+ dns_name_t qname;
+ dns_rdatatype_t qtype;
+ isc_stdtime_t lame_timer;
+
+ ISC_LINK(dns_adblameinfo_t) plink;
+};
+
+/*%
+ * An address entry. It holds quite a bit of information about addresses,
+ * including edns state (in "flags"), rtt, and of course the address of
+ * the host.
+ */
+struct dns_adbentry {
+ unsigned int magic;
+
+ int lock_bucket;
+ unsigned int refcnt;
+ unsigned int nh;
+
+ unsigned int flags;
+ unsigned int srtt;
+ uint16_t udpsize;
+ unsigned int completed;
+ unsigned int timeouts;
+ unsigned char plain;
+ unsigned char plainto;
+ unsigned char edns;
+ unsigned char ednsto;
+
+ uint8_t mode;
+ atomic_uint_fast32_t quota;
+ atomic_uint_fast32_t active;
+ double atr;
+
+ isc_sockaddr_t sockaddr;
+ unsigned char *cookie;
+ uint16_t cookielen;
+
+ isc_stdtime_t expires;
+ isc_stdtime_t lastage;
+ /*%<
+ * A nonzero 'expires' field indicates that the entry should
+ * persist until that time. This allows entries found
+ * using dns_adb_findaddrinfo() to persist for a limited time
+ * even though they are not necessarily associated with a
+ * name.
+ */
+
+ ISC_LIST(dns_adblameinfo_t) lameinfo;
+ ISC_LINK(dns_adbentry_t) plink;
+};
+
+/*
+ * Internal functions (and prototypes).
+ */
+static dns_adbname_t *
+new_adbname(dns_adb_t *, const dns_name_t *);
+static void
+free_adbname(dns_adb_t *, dns_adbname_t **);
+static dns_adbnamehook_t *
+new_adbnamehook(dns_adb_t *, dns_adbentry_t *);
+static void
+free_adbnamehook(dns_adb_t *, dns_adbnamehook_t **);
+static dns_adblameinfo_t *
+new_adblameinfo(dns_adb_t *, const dns_name_t *, dns_rdatatype_t);
+static void
+free_adblameinfo(dns_adb_t *, dns_adblameinfo_t **);
+static dns_adbentry_t *
+new_adbentry(dns_adb_t *);
+static void
+free_adbentry(dns_adb_t *, dns_adbentry_t **);
+static dns_adbfind_t *
+new_adbfind(dns_adb_t *);
+static bool
+free_adbfind(dns_adb_t *, dns_adbfind_t **);
+static dns_adbaddrinfo_t *
+new_adbaddrinfo(dns_adb_t *, dns_adbentry_t *, in_port_t);
+static dns_adbfetch_t *
+new_adbfetch(dns_adb_t *);
+static void
+free_adbfetch(dns_adb_t *, dns_adbfetch_t **);
+static dns_adbname_t *
+find_name_and_lock(dns_adb_t *, const dns_name_t *, unsigned int, int *);
+static dns_adbentry_t *
+find_entry_and_lock(dns_adb_t *, const isc_sockaddr_t *, int *, isc_stdtime_t);
+static void
+dump_adb(dns_adb_t *, FILE *, bool debug, isc_stdtime_t);
+static void
+print_dns_name(FILE *, const dns_name_t *);
+static void
+print_namehook_list(FILE *, const char *legend, dns_adb_t *adb,
+ dns_adbnamehooklist_t *list, bool debug, isc_stdtime_t now);
+static void
+print_find_list(FILE *, dns_adbname_t *);
+static void
+print_fetch_list(FILE *, dns_adbname_t *);
+static bool
+dec_adb_irefcnt(dns_adb_t *);
+static void
+inc_adb_irefcnt(dns_adb_t *);
+static void
+inc_adb_erefcnt(dns_adb_t *);
+static void
+inc_entry_refcnt(dns_adb_t *, dns_adbentry_t *, bool);
+static bool
+dec_entry_refcnt(dns_adb_t *, bool, dns_adbentry_t *, bool, isc_stdtime_t);
+static void
+violate_locking_hierarchy(isc_mutex_t *, isc_mutex_t *);
+static bool
+clean_namehooks(dns_adb_t *, dns_adbnamehooklist_t *);
+static void
+clean_target(dns_adb_t *, dns_name_t *);
+static void
+clean_finds_at_name(dns_adbname_t *, isc_eventtype_t, unsigned int);
+static bool
+check_expire_namehooks(dns_adbname_t *, isc_stdtime_t);
+static bool
+check_expire_entry(dns_adb_t *, dns_adbentry_t **, isc_stdtime_t);
+static void
+cancel_fetches_at_name(dns_adbname_t *);
+static isc_result_t
+dbfind_name(dns_adbname_t *, isc_stdtime_t, dns_rdatatype_t);
+static isc_result_t
+fetch_name(dns_adbname_t *, bool, unsigned int, isc_counter_t *qc,
+ dns_rdatatype_t);
+static void
+check_exit(dns_adb_t *);
+static void
+destroy(dns_adb_t *);
+static bool
+shutdown_names(dns_adb_t *);
+static bool
+shutdown_entries(dns_adb_t *);
+static void
+link_name(dns_adb_t *, int, dns_adbname_t *);
+static bool
+unlink_name(dns_adb_t *, dns_adbname_t *);
+static void
+link_entry(dns_adb_t *, int, dns_adbentry_t *);
+static bool
+unlink_entry(dns_adb_t *, dns_adbentry_t *);
+static bool
+kill_name(dns_adbname_t **, isc_eventtype_t);
+static void
+water(void *, int);
+static void
+dump_entry(FILE *, dns_adb_t *, dns_adbentry_t *, bool, isc_stdtime_t);
+static void
+adjustsrtt(dns_adbaddrinfo_t *addr, unsigned int rtt, unsigned int factor,
+ isc_stdtime_t now);
+static void
+shutdown_task(isc_task_t *task, isc_event_t *ev);
+static void
+log_quota(dns_adbentry_t *entry, const char *fmt, ...) ISC_FORMAT_PRINTF(2, 3);
+
+/*
+ * Private flag(s) for adbfind objects. These are used internally and
+ * are not meant to be seen or used by the caller; however, we use the
+ * same flags field as for DNS_ADBFIND_xxx flags, so we must be careful
+ * that there is no overlap between these values and those. To make it
+ * easier, we will number these starting from the most significant bit
+ * instead of the least significant.
+ */
+enum {
+ FIND_EVENT_SENT = 1 << 31,
+ FIND_EVENT_FREED = 1 << 30,
+};
+#define FIND_EVENTSENT(h) (((h)->flags & FIND_EVENT_SENT) != 0)
+#define FIND_EVENTFREED(h) (((h)->flags & FIND_EVENT_FREED) != 0)
+
+/*
+ * Private flag(s) for adbname objects.
+ */
+enum {
+ NAME_IS_DEAD = 1 << 31,
+ NAME_NEEDS_POKE = 1 << 30,
+};
+#define NAME_DEAD(n) (((n)->flags & NAME_IS_DEAD) != 0)
+#define NAME_NEEDSPOKE(n) (((n)->flags & NAME_NEEDS_POKE) != 0)
+#define NAME_GLUEOK(n) (((n)->flags & DNS_ADBFIND_GLUEOK) != 0)
+#define NAME_HINTOK(n) (((n)->flags & DNS_ADBFIND_HINTOK) != 0)
+
+/*
+ * Private flag(s) for adbentry objects. Note that these will also
+ * be used for addrinfo flags, and in resolver.c we'll use the same
+ * field for FCTX_ADDRINFO_xxx flags to store information about remote
+ * servers, so we must be careful that there is no overlap between
+ * these values and those. To make it easier, we will number these
+ * starting from the most significant bit instead of the least
+ * significant.
+ */
+enum {
+ ENTRY_IS_DEAD = 1 << 31,
+};
+
+/*
+ * To the name, address classes are all that really exist. If it has a
+ * V6 address it doesn't care if it came from a AAAA query.
+ */
+#define NAME_HAS_V4(n) (!ISC_LIST_EMPTY((n)->v4))
+#define NAME_HAS_V6(n) (!ISC_LIST_EMPTY((n)->v6))
+#define NAME_HAS_ADDRS(n) (NAME_HAS_V4(n) || NAME_HAS_V6(n))
+
+/*
+ * Fetches are broken out into A and AAAA types. In some cases,
+ * however, it makes more sense to test for a particular class of fetches,
+ * like V4 or V6 above.
+ */
+#define NAME_FETCH_A(n) ((n)->fetch_a != NULL)
+#define NAME_FETCH_AAAA(n) ((n)->fetch_aaaa != NULL)
+#define NAME_FETCH(n) (NAME_FETCH_A(n) || NAME_FETCH_AAAA(n))
+
+/*
+ * Find options and tests to see if there are addresses on the list.
+ */
+#define FIND_WANTEVENT(fn) (((fn)->options & DNS_ADBFIND_WANTEVENT) != 0)
+#define FIND_WANTEMPTYEVENT(fn) (((fn)->options & DNS_ADBFIND_EMPTYEVENT) != 0)
+#define FIND_AVOIDFETCHES(fn) (((fn)->options & DNS_ADBFIND_AVOIDFETCHES) != 0)
+#define FIND_STARTATZONE(fn) (((fn)->options & DNS_ADBFIND_STARTATZONE) != 0)
+#define FIND_HINTOK(fn) (((fn)->options & DNS_ADBFIND_HINTOK) != 0)
+#define FIND_GLUEOK(fn) (((fn)->options & DNS_ADBFIND_GLUEOK) != 0)
+#define FIND_HAS_ADDRS(fn) (!ISC_LIST_EMPTY((fn)->list))
+#define FIND_RETURNLAME(fn) (((fn)->options & DNS_ADBFIND_RETURNLAME) != 0)
+#define FIND_NOFETCH(fn) (((fn)->options & DNS_ADBFIND_NOFETCH) != 0)
+
+/*
+ * These are currently used on simple unsigned ints, so they are
+ * not really associated with any particular type.
+ */
+#define WANT_INET(x) (((x)&DNS_ADBFIND_INET) != 0)
+#define WANT_INET6(x) (((x)&DNS_ADBFIND_INET6) != 0)
+
+#define EXPIRE_OK(exp, now) ((exp == INT_MAX) || (exp < now))
+
+/*
+ * Find out if the flags on a name (nf) indicate if it is a hint or
+ * glue, and compare this to the appropriate bits set in o, to see if
+ * this is ok.
+ */
+#define GLUE_OK(nf, o) (!NAME_GLUEOK(nf) || (((o)&DNS_ADBFIND_GLUEOK) != 0))
+#define HINT_OK(nf, o) (!NAME_HINTOK(nf) || (((o)&DNS_ADBFIND_HINTOK) != 0))
+#define GLUEHINT_OK(nf, o) (GLUE_OK(nf, o) || HINT_OK(nf, o))
+#define STARTATZONE_MATCHES(nf, o) \
+ (((nf)->flags & DNS_ADBFIND_STARTATZONE) == \
+ ((o)&DNS_ADBFIND_STARTATZONE))
+
+#define ENTER_LEVEL ISC_LOG_DEBUG(50)
+#define EXIT_LEVEL ENTER_LEVEL
+#define CLEAN_LEVEL ISC_LOG_DEBUG(100)
+#define DEF_LEVEL ISC_LOG_DEBUG(5)
+#define NCACHE_LEVEL ISC_LOG_DEBUG(20)
+
+#define NCACHE_RESULT(r) \
+ ((r) == DNS_R_NCACHENXDOMAIN || (r) == DNS_R_NCACHENXRRSET)
+#define AUTH_NX(r) ((r) == DNS_R_NXDOMAIN || (r) == DNS_R_NXRRSET)
+#define NXDOMAIN_RESULT(r) \
+ ((r) == DNS_R_NXDOMAIN || (r) == DNS_R_NCACHENXDOMAIN)
+#define NXRRSET_RESULT(r) \
+ ((r) == DNS_R_NCACHENXRRSET || (r) == DNS_R_NXRRSET || \
+ (r) == DNS_R_HINTNXRRSET)
+
+/*
+ * Error state rankings.
+ */
+
+#define FIND_ERR_SUCCESS 0 /* highest rank */
+#define FIND_ERR_CANCELED 1
+#define FIND_ERR_FAILURE 2
+#define FIND_ERR_NXDOMAIN 3
+#define FIND_ERR_NXRRSET 4
+#define FIND_ERR_UNEXPECTED 5
+#define FIND_ERR_NOTFOUND 6
+#define FIND_ERR_MAX 7
+
+static const char *errnames[] = { "success", "canceled", "failure",
+ "nxdomain", "nxrrset", "unexpected",
+ "not_found" };
+
+#define NEWERR(old, new) (ISC_MIN((old), (new)))
+
+static isc_result_t find_err_map[FIND_ERR_MAX] = {
+ ISC_R_SUCCESS, ISC_R_CANCELED, ISC_R_FAILURE, DNS_R_NXDOMAIN,
+ DNS_R_NXRRSET, ISC_R_UNEXPECTED, ISC_R_NOTFOUND /* not YET found */
+};
+
+static void
+DP(int level, const char *format, ...) ISC_FORMAT_PRINTF(2, 3);
+
+static void
+DP(int level, const char *format, ...) {
+ va_list args;
+
+ va_start(args, format);
+ isc_log_vwrite(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB,
+ level, format, args);
+ va_end(args);
+}
+
+/*%
+ * Increment resolver-related statistics counters.
+ */
+static void
+inc_stats(dns_adb_t *adb, isc_statscounter_t counter) {
+ if (adb->view->resstats != NULL) {
+ isc_stats_increment(adb->view->resstats, counter);
+ }
+}
+
+/*%
+ * Set adb-related statistics counters.
+ */
+static void
+set_adbstat(dns_adb_t *adb, uint64_t val, isc_statscounter_t counter) {
+ if (adb->view->adbstats != NULL) {
+ isc_stats_set(adb->view->adbstats, val, counter);
+ }
+}
+
+static void
+dec_adbstats(dns_adb_t *adb, isc_statscounter_t counter) {
+ if (adb->view->adbstats != NULL) {
+ isc_stats_decrement(adb->view->adbstats, counter);
+ }
+}
+
+static void
+inc_adbstats(dns_adb_t *adb, isc_statscounter_t counter) {
+ if (adb->view->adbstats != NULL) {
+ isc_stats_increment(adb->view->adbstats, counter);
+ }
+}
+
+static dns_ttl_t
+ttlclamp(dns_ttl_t ttl) {
+ if (ttl < ADB_CACHE_MINIMUM) {
+ ttl = ADB_CACHE_MINIMUM;
+ }
+ if (ttl > ADB_CACHE_MAXIMUM) {
+ ttl = ADB_CACHE_MAXIMUM;
+ }
+
+ return (ttl);
+}
+
+/*
+ * Hashing is most efficient if the number of buckets is prime.
+ * The sequence below is the closest previous primes to 2^n and
+ * 1.5 * 2^n, for values of n from 10 to 28. (The tables will
+ * no longer grow beyond 2^28 entries.)
+ */
+static const unsigned nbuckets[] = {
+ 1021, 1531, 2039, 3067, 4093, 6143,
+ 8191, 12281, 16381, 24571, 32749, 49193,
+ 65521, 98299, 131071, 199603, 262139, 393209,
+ 524287, 768431, 1048573, 1572853, 2097143, 3145721,
+ 4194301, 6291449, 8388593, 12582893, 16777213, 25165813,
+ 33554393, 50331599, 67108859, 100663291, 134217689, 201326557,
+ 268535431, 0
+};
+
+static void
+grow_entries(isc_task_t *task, isc_event_t *ev) {
+ dns_adb_t *adb;
+ dns_adbentry_t *e;
+ dns_adbentrylist_t *newdeadentries = NULL;
+ dns_adbentrylist_t *newentries = NULL;
+ bool *newentry_sd = NULL;
+ isc_mutex_t *newentrylocks = NULL;
+ isc_result_t result;
+ unsigned int *newentry_refcnt = NULL;
+ unsigned int i, n, bucket;
+
+ adb = ev->ev_arg;
+ INSIST(DNS_ADB_VALID(adb));
+
+ isc_event_free(&ev);
+
+ result = isc_task_beginexclusive(task);
+ if (result != ISC_R_SUCCESS) {
+ goto check_exit;
+ }
+
+ i = 0;
+ while (nbuckets[i] != 0 && adb->nentries >= nbuckets[i]) {
+ i++;
+ }
+ if (nbuckets[i] != 0) {
+ n = nbuckets[i];
+ } else {
+ goto done;
+ }
+
+ DP(ISC_LOG_INFO, "adb: grow_entries to %u starting", n);
+
+ /*
+ * Are we shutting down?
+ */
+ for (i = 0; i < adb->nentries; i++) {
+ if (adb->entry_sd[i]) {
+ goto cleanup;
+
+ /*
+ * Grab all the resources we need.
+ */
+ }
+ }
+
+ /*
+ * Grab all the resources we need.
+ */
+ newentries = isc_mem_get(adb->hmctx, sizeof(*newentries) * n);
+ newdeadentries = isc_mem_get(adb->hmctx, sizeof(*newdeadentries) * n);
+ newentrylocks = isc_mem_get(adb->hmctx, sizeof(*newentrylocks) * n);
+ newentry_sd = isc_mem_get(adb->hmctx, sizeof(*newentry_sd) * n);
+ newentry_refcnt = isc_mem_get(adb->hmctx, sizeof(*newentry_refcnt) * n);
+
+ /*
+ * Initialise the new resources.
+ */
+ isc_mutexblock_init(newentrylocks, n);
+
+ for (i = 0; i < n; i++) {
+ ISC_LIST_INIT(newentries[i]);
+ ISC_LIST_INIT(newdeadentries[i]);
+ newentry_sd[i] = false;
+ newentry_refcnt[i] = 0;
+ adb->irefcnt++;
+ }
+
+ /*
+ * Move entries to new arrays.
+ */
+ for (i = 0; i < adb->nentries; i++) {
+ e = ISC_LIST_HEAD(adb->entries[i]);
+ while (e != NULL) {
+ ISC_LIST_UNLINK(adb->entries[i], e, plink);
+ bucket = isc_sockaddr_hash(&e->sockaddr, true) % n;
+ e->lock_bucket = bucket;
+ ISC_LIST_APPEND(newentries[bucket], e, plink);
+ INSIST(adb->entry_refcnt[i] > 0);
+ adb->entry_refcnt[i]--;
+ newentry_refcnt[bucket]++;
+ e = ISC_LIST_HEAD(adb->entries[i]);
+ }
+ e = ISC_LIST_HEAD(adb->deadentries[i]);
+ while (e != NULL) {
+ ISC_LIST_UNLINK(adb->deadentries[i], e, plink);
+ bucket = isc_sockaddr_hash(&e->sockaddr, true) % n;
+ e->lock_bucket = bucket;
+ ISC_LIST_APPEND(newdeadentries[bucket], e, plink);
+ INSIST(adb->entry_refcnt[i] > 0);
+ adb->entry_refcnt[i]--;
+ newentry_refcnt[bucket]++;
+ e = ISC_LIST_HEAD(adb->deadentries[i]);
+ }
+ INSIST(adb->entry_refcnt[i] == 0);
+ adb->irefcnt--;
+ }
+
+ /*
+ * Cleanup old resources.
+ */
+ isc_mutexblock_destroy(adb->entrylocks, adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entries,
+ sizeof(*adb->entries) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->deadentries,
+ sizeof(*adb->deadentries) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entrylocks,
+ sizeof(*adb->entrylocks) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entry_sd,
+ sizeof(*adb->entry_sd) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entry_refcnt,
+ sizeof(*adb->entry_refcnt) * adb->nentries);
+
+ /*
+ * Install new resources.
+ */
+ adb->entries = newentries;
+ adb->deadentries = newdeadentries;
+ adb->entrylocks = newentrylocks;
+ adb->entry_sd = newentry_sd;
+ adb->entry_refcnt = newentry_refcnt;
+ adb->nentries = n;
+
+ set_adbstat(adb, adb->nentries, dns_adbstats_nentries);
+
+ /*
+ * Only on success do we set adb->growentries_sent to false.
+ * This will prevent us being continuously being called on error.
+ */
+ adb->growentries_sent = false;
+ goto done;
+
+cleanup:
+ if (newentries != NULL) {
+ isc_mem_put(adb->mctx, newentries, sizeof(*newentries) * n);
+ }
+ if (newdeadentries != NULL) {
+ isc_mem_put(adb->mctx, newdeadentries,
+ sizeof(*newdeadentries) * n);
+ }
+ if (newentrylocks != NULL) {
+ isc_mem_put(adb->mctx, newentrylocks,
+ sizeof(*newentrylocks) * n);
+ }
+ if (newentry_sd != NULL) {
+ isc_mem_put(adb->mctx, newentry_sd, sizeof(*newentry_sd) * n);
+ }
+ if (newentry_refcnt != NULL) {
+ isc_mem_put(adb->mctx, newentry_refcnt,
+ sizeof(*newentry_refcnt) * n);
+ }
+done:
+ isc_task_endexclusive(task);
+
+check_exit:
+ LOCK(&adb->lock);
+ if (dec_adb_irefcnt(adb)) {
+ check_exit(adb);
+ }
+ UNLOCK(&adb->lock);
+ DP(ISC_LOG_INFO, "adb: grow_entries finished");
+}
+
+static void
+grow_names(isc_task_t *task, isc_event_t *ev) {
+ dns_adb_t *adb;
+ dns_adbname_t *name;
+ dns_adbnamelist_t *newdeadnames = NULL;
+ dns_adbnamelist_t *newnames = NULL;
+ bool *newname_sd = NULL;
+ isc_mutex_t *newnamelocks = NULL;
+ isc_result_t result;
+ unsigned int *newname_refcnt = NULL;
+ unsigned int i, n;
+ unsigned int bucket;
+
+ adb = ev->ev_arg;
+ INSIST(DNS_ADB_VALID(adb));
+
+ isc_event_free(&ev);
+
+ result = isc_task_beginexclusive(task);
+ if (result != ISC_R_SUCCESS) {
+ goto check_exit;
+ }
+
+ i = 0;
+ while (nbuckets[i] != 0 && adb->nnames >= nbuckets[i]) {
+ i++;
+ }
+ if (nbuckets[i] != 0) {
+ n = nbuckets[i];
+ } else {
+ goto done;
+ }
+
+ DP(ISC_LOG_INFO, "adb: grow_names to %u starting", n);
+
+ /*
+ * Are we shutting down?
+ */
+ for (i = 0; i < adb->nnames; i++) {
+ if (adb->name_sd[i]) {
+ goto cleanup;
+
+ /*
+ * Grab all the resources we need.
+ */
+ }
+ }
+
+ /*
+ * Grab all the resources we need.
+ */
+ newnames = isc_mem_get(adb->hmctx, sizeof(*newnames) * n);
+ newdeadnames = isc_mem_get(adb->hmctx, sizeof(*newdeadnames) * n);
+ newnamelocks = isc_mem_get(adb->hmctx, sizeof(*newnamelocks) * n);
+ newname_sd = isc_mem_get(adb->hmctx, sizeof(*newname_sd) * n);
+ newname_refcnt = isc_mem_get(adb->hmctx, sizeof(*newname_refcnt) * n);
+
+ /*
+ * Initialise the new resources.
+ */
+ isc_mutexblock_init(newnamelocks, n);
+
+ for (i = 0; i < n; i++) {
+ ISC_LIST_INIT(newnames[i]);
+ ISC_LIST_INIT(newdeadnames[i]);
+ newname_sd[i] = false;
+ newname_refcnt[i] = 0;
+ adb->irefcnt++;
+ }
+
+ /*
+ * Move names to new arrays.
+ */
+ for (i = 0; i < adb->nnames; i++) {
+ name = ISC_LIST_HEAD(adb->names[i]);
+ while (name != NULL) {
+ ISC_LIST_UNLINK(adb->names[i], name, plink);
+ bucket = dns_name_fullhash(&name->name, true) % n;
+ name->lock_bucket = bucket;
+ ISC_LIST_APPEND(newnames[bucket], name, plink);
+ INSIST(adb->name_refcnt[i] > 0);
+ adb->name_refcnt[i]--;
+ newname_refcnt[bucket]++;
+ name = ISC_LIST_HEAD(adb->names[i]);
+ }
+ name = ISC_LIST_HEAD(adb->deadnames[i]);
+ while (name != NULL) {
+ ISC_LIST_UNLINK(adb->deadnames[i], name, plink);
+ bucket = dns_name_fullhash(&name->name, true) % n;
+ name->lock_bucket = bucket;
+ ISC_LIST_APPEND(newdeadnames[bucket], name, plink);
+ INSIST(adb->name_refcnt[i] > 0);
+ adb->name_refcnt[i]--;
+ newname_refcnt[bucket]++;
+ name = ISC_LIST_HEAD(adb->deadnames[i]);
+ }
+ INSIST(adb->name_refcnt[i] == 0);
+ adb->irefcnt--;
+ }
+
+ /*
+ * Cleanup old resources.
+ */
+ isc_mutexblock_destroy(adb->namelocks, adb->nnames);
+ isc_mem_put(adb->hmctx, adb->names, sizeof(*adb->names) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->deadnames,
+ sizeof(*adb->deadnames) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->namelocks,
+ sizeof(*adb->namelocks) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->name_sd,
+ sizeof(*adb->name_sd) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->name_refcnt,
+ sizeof(*adb->name_refcnt) * adb->nnames);
+
+ /*
+ * Install new resources.
+ */
+ adb->names = newnames;
+ adb->deadnames = newdeadnames;
+ adb->namelocks = newnamelocks;
+ adb->name_sd = newname_sd;
+ adb->name_refcnt = newname_refcnt;
+ adb->nnames = n;
+
+ set_adbstat(adb, adb->nnames, dns_adbstats_nnames);
+
+ /*
+ * Only on success do we set adb->grownames_sent to false.
+ * This will prevent us being continuously being called on error.
+ */
+ adb->grownames_sent = false;
+ goto done;
+
+cleanup:
+ if (newnames != NULL) {
+ isc_mem_put(adb->hmctx, newnames, sizeof(*newnames) * n);
+ }
+ if (newdeadnames != NULL) {
+ isc_mem_put(adb->hmctx, newdeadnames,
+ sizeof(*newdeadnames) * n);
+ }
+ if (newnamelocks != NULL) {
+ isc_mem_put(adb->hmctx, newnamelocks,
+ sizeof(*newnamelocks) * n);
+ }
+ if (newname_sd != NULL) {
+ isc_mem_put(adb->hmctx, newname_sd, sizeof(*newname_sd) * n);
+ }
+ if (newname_refcnt != NULL) {
+ isc_mem_put(adb->hmctx, newname_refcnt,
+ sizeof(*newname_refcnt) * n);
+ }
+done:
+ isc_task_endexclusive(task);
+
+check_exit:
+ LOCK(&adb->lock);
+ if (dec_adb_irefcnt(adb)) {
+ check_exit(adb);
+ }
+ UNLOCK(&adb->lock);
+ DP(ISC_LOG_INFO, "adb: grow_names finished");
+}
+
+/*
+ * Requires the adbname bucket be locked and that no entry buckets be locked.
+ *
+ * This code handles A and AAAA rdatasets only.
+ */
+static isc_result_t
+import_rdataset(dns_adbname_t *adbname, dns_rdataset_t *rdataset,
+ isc_stdtime_t now) {
+ isc_result_t result;
+ dns_adb_t *adb = NULL;
+ dns_adbnamehook_t *nh = NULL;
+ dns_adbnamehook_t *anh = NULL;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ struct in_addr ina;
+ struct in6_addr in6a;
+ isc_sockaddr_t sockaddr;
+ dns_adbentry_t *foundentry = NULL; /* NO CLEAN UP! */
+ int addr_bucket;
+ bool new_addresses_added;
+ dns_rdatatype_t rdtype;
+ dns_adbnamehooklist_t *hookhead = NULL;
+
+ INSIST(DNS_ADBNAME_VALID(adbname));
+ adb = adbname->adb;
+ INSIST(DNS_ADB_VALID(adb));
+
+ rdtype = rdataset->type;
+ INSIST((rdtype == dns_rdatatype_a) || (rdtype == dns_rdatatype_aaaa));
+
+ addr_bucket = DNS_ADB_INVALIDBUCKET;
+ new_addresses_added = false;
+
+ result = dns_rdataset_first(rdataset);
+ while (result == ISC_R_SUCCESS) {
+ dns_rdata_reset(&rdata);
+ dns_rdataset_current(rdataset, &rdata);
+ if (rdtype == dns_rdatatype_a) {
+ INSIST(rdata.length == 4);
+ memmove(&ina.s_addr, rdata.data, 4);
+ isc_sockaddr_fromin(&sockaddr, &ina, 0);
+ hookhead = &adbname->v4;
+ } else {
+ INSIST(rdata.length == 16);
+ memmove(in6a.s6_addr, rdata.data, 16);
+ isc_sockaddr_fromin6(&sockaddr, &in6a, 0);
+ hookhead = &adbname->v6;
+ }
+
+ INSIST(nh == NULL);
+ nh = new_adbnamehook(adb, NULL);
+ foundentry = find_entry_and_lock(adb, &sockaddr, &addr_bucket,
+ now);
+ if (foundentry == NULL) {
+ dns_adbentry_t *entry;
+
+ entry = new_adbentry(adb);
+ entry->sockaddr = sockaddr;
+ entry->refcnt = 1;
+ entry->nh = 1;
+
+ nh->entry = entry;
+
+ link_entry(adb, addr_bucket, entry);
+ } else {
+ for (anh = ISC_LIST_HEAD(*hookhead); anh != NULL;
+ anh = ISC_LIST_NEXT(anh, plink))
+ {
+ if (anh->entry == foundentry) {
+ break;
+ }
+ }
+ if (anh == NULL) {
+ foundentry->refcnt++;
+ foundentry->nh++;
+ nh->entry = foundentry;
+ } else {
+ free_adbnamehook(adb, &nh);
+ }
+ }
+
+ new_addresses_added = true;
+ if (nh != NULL) {
+ ISC_LIST_APPEND(*hookhead, nh, plink);
+ }
+ nh = NULL;
+ result = dns_rdataset_next(rdataset);
+ }
+
+ if (addr_bucket != DNS_ADB_INVALIDBUCKET) {
+ UNLOCK(&adb->entrylocks[addr_bucket]);
+ }
+
+ if (rdataset->trust == dns_trust_glue ||
+ rdataset->trust == dns_trust_additional)
+ {
+ rdataset->ttl = ADB_CACHE_MINIMUM;
+ } else if (rdataset->trust == dns_trust_ultimate) {
+ rdataset->ttl = 0;
+ } else {
+ rdataset->ttl = ttlclamp(rdataset->ttl);
+ }
+
+ if (rdtype == dns_rdatatype_a) {
+ DP(NCACHE_LEVEL, "expire_v4 set to MIN(%u,%u) import_rdataset",
+ adbname->expire_v4, now + rdataset->ttl);
+ adbname->expire_v4 = ISC_MIN(
+ adbname->expire_v4,
+ ISC_MIN(now + ADB_ENTRY_WINDOW, now + rdataset->ttl));
+ } else {
+ DP(NCACHE_LEVEL, "expire_v6 set to MIN(%u,%u) import_rdataset",
+ adbname->expire_v6, now + rdataset->ttl);
+ adbname->expire_v6 = ISC_MIN(
+ adbname->expire_v6,
+ ISC_MIN(now + ADB_ENTRY_WINDOW, now + rdataset->ttl));
+ }
+
+ if (new_addresses_added) {
+ /*
+ * Lie a little here. This is more or less so code that cares
+ * can find out if any new information was added or not.
+ */
+ return (ISC_R_SUCCESS);
+ }
+
+ return (result);
+}
+
+/*
+ * Requires the name's bucket be locked.
+ */
+static bool
+kill_name(dns_adbname_t **n, isc_eventtype_t ev) {
+ dns_adbname_t *name;
+ bool result = false;
+ bool result4, result6;
+ int bucket;
+ dns_adb_t *adb;
+
+ INSIST(n != NULL);
+ name = *n;
+ *n = NULL;
+ INSIST(DNS_ADBNAME_VALID(name));
+ adb = name->adb;
+ INSIST(DNS_ADB_VALID(adb));
+
+ DP(DEF_LEVEL, "killing name %p", name);
+
+ /*
+ * If we're dead already, just check to see if we should go
+ * away now or not.
+ */
+ if (NAME_DEAD(name) && !NAME_FETCH(name)) {
+ result = unlink_name(adb, name);
+ free_adbname(adb, &name);
+ if (result) {
+ result = dec_adb_irefcnt(adb);
+ }
+ return (result);
+ }
+
+ /*
+ * Clean up the name's various lists. These two are destructive
+ * in that they will always empty the list.
+ */
+ clean_finds_at_name(name, ev, DNS_ADBFIND_ADDRESSMASK);
+ result4 = clean_namehooks(adb, &name->v4);
+ result6 = clean_namehooks(adb, &name->v6);
+ clean_target(adb, &name->target);
+ result = (result4 || result6);
+
+ /*
+ * If fetches are running, cancel them. If none are running, we can
+ * just kill the name here.
+ */
+ if (!NAME_FETCH(name)) {
+ INSIST(!result);
+ result = unlink_name(adb, name);
+ free_adbname(adb, &name);
+ if (result) {
+ result = dec_adb_irefcnt(adb);
+ }
+ } else {
+ cancel_fetches_at_name(name);
+ if (!NAME_DEAD(name)) {
+ bucket = name->lock_bucket;
+ ISC_LIST_UNLINK(adb->names[bucket], name, plink);
+ ISC_LIST_APPEND(adb->deadnames[bucket], name, plink);
+ name->flags |= NAME_IS_DEAD;
+ }
+ }
+ return (result);
+}
+
+/*
+ * Requires the name's bucket be locked and no entry buckets be locked.
+ */
+static bool
+check_expire_namehooks(dns_adbname_t *name, isc_stdtime_t now) {
+ dns_adb_t *adb;
+ bool result4 = false;
+ bool result6 = false;
+
+ INSIST(DNS_ADBNAME_VALID(name));
+ adb = name->adb;
+ INSIST(DNS_ADB_VALID(adb));
+
+ /*
+ * Check to see if we need to remove the v4 addresses
+ */
+ if (!NAME_FETCH_A(name) && EXPIRE_OK(name->expire_v4, now)) {
+ if (NAME_HAS_V4(name)) {
+ DP(DEF_LEVEL, "expiring v4 for name %p", name);
+ result4 = clean_namehooks(adb, &name->v4);
+ name->partial_result &= ~DNS_ADBFIND_INET;
+ }
+ name->expire_v4 = INT_MAX;
+ name->fetch_err = FIND_ERR_UNEXPECTED;
+ }
+
+ /*
+ * Check to see if we need to remove the v6 addresses
+ */
+ if (!NAME_FETCH_AAAA(name) && EXPIRE_OK(name->expire_v6, now)) {
+ if (NAME_HAS_V6(name)) {
+ DP(DEF_LEVEL, "expiring v6 for name %p", name);
+ result6 = clean_namehooks(adb, &name->v6);
+ name->partial_result &= ~DNS_ADBFIND_INET6;
+ }
+ name->expire_v6 = INT_MAX;
+ name->fetch6_err = FIND_ERR_UNEXPECTED;
+ }
+
+ /*
+ * Check to see if we need to remove the alias target.
+ */
+ if (EXPIRE_OK(name->expire_target, now)) {
+ clean_target(adb, &name->target);
+ name->expire_target = INT_MAX;
+ }
+ return (result4 || result6);
+}
+
+/*
+ * Requires the name's bucket be locked.
+ */
+static void
+link_name(dns_adb_t *adb, int bucket, dns_adbname_t *name) {
+ INSIST(name->lock_bucket == DNS_ADB_INVALIDBUCKET);
+
+ ISC_LIST_PREPEND(adb->names[bucket], name, plink);
+ name->lock_bucket = bucket;
+ adb->name_refcnt[bucket]++;
+}
+
+/*
+ * Requires the name's bucket be locked.
+ */
+static bool
+unlink_name(dns_adb_t *adb, dns_adbname_t *name) {
+ int bucket;
+ bool result = false;
+
+ bucket = name->lock_bucket;
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+
+ if (NAME_DEAD(name)) {
+ ISC_LIST_UNLINK(adb->deadnames[bucket], name, plink);
+ } else {
+ ISC_LIST_UNLINK(adb->names[bucket], name, plink);
+ }
+ name->lock_bucket = DNS_ADB_INVALIDBUCKET;
+ INSIST(adb->name_refcnt[bucket] > 0);
+ adb->name_refcnt[bucket]--;
+ if (adb->name_sd[bucket] && adb->name_refcnt[bucket] == 0) {
+ result = true;
+ }
+ return (result);
+}
+
+/*
+ * Requires the entry's bucket be locked.
+ */
+static void
+link_entry(dns_adb_t *adb, int bucket, dns_adbentry_t *entry) {
+ int i;
+ dns_adbentry_t *e;
+
+ if (isc_mem_isovermem(adb->mctx)) {
+ for (i = 0; i < 2; i++) {
+ e = ISC_LIST_TAIL(adb->entries[bucket]);
+ if (e == NULL) {
+ break;
+ }
+ if (e->refcnt == 0) {
+ unlink_entry(adb, e);
+ free_adbentry(adb, &e);
+ continue;
+ }
+ INSIST((e->flags & ENTRY_IS_DEAD) == 0);
+ e->flags |= ENTRY_IS_DEAD;
+ ISC_LIST_UNLINK(adb->entries[bucket], e, plink);
+ ISC_LIST_PREPEND(adb->deadentries[bucket], e, plink);
+ }
+ }
+
+ ISC_LIST_PREPEND(adb->entries[bucket], entry, plink);
+ entry->lock_bucket = bucket;
+ adb->entry_refcnt[bucket]++;
+}
+
+/*
+ * Requires the entry's bucket be locked.
+ */
+static bool
+unlink_entry(dns_adb_t *adb, dns_adbentry_t *entry) {
+ int bucket;
+ bool result = false;
+
+ bucket = entry->lock_bucket;
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+
+ if ((entry->flags & ENTRY_IS_DEAD) != 0) {
+ ISC_LIST_UNLINK(adb->deadentries[bucket], entry, plink);
+ } else {
+ ISC_LIST_UNLINK(adb->entries[bucket], entry, plink);
+ }
+ entry->lock_bucket = DNS_ADB_INVALIDBUCKET;
+ INSIST(adb->entry_refcnt[bucket] > 0);
+ adb->entry_refcnt[bucket]--;
+ if (adb->entry_sd[bucket] && adb->entry_refcnt[bucket] == 0) {
+ result = true;
+ }
+ return (result);
+}
+
+static void
+violate_locking_hierarchy(isc_mutex_t *have, isc_mutex_t *want) {
+ if (isc_mutex_trylock(want) != ISC_R_SUCCESS) {
+ UNLOCK(have);
+ LOCK(want);
+ LOCK(have);
+ }
+}
+
+/*
+ * The ADB _MUST_ be locked before calling. Also, exit conditions must be
+ * checked after calling this function.
+ */
+static bool
+shutdown_names(dns_adb_t *adb) {
+ unsigned int bucket;
+ bool result = false;
+ dns_adbname_t *name;
+ dns_adbname_t *next_name;
+
+ for (bucket = 0; bucket < adb->nnames; bucket++) {
+ LOCK(&adb->namelocks[bucket]);
+ adb->name_sd[bucket] = true;
+
+ name = ISC_LIST_HEAD(adb->names[bucket]);
+ if (name == NULL) {
+ /*
+ * This bucket has no names. We must decrement the
+ * irefcnt ourselves, since it will not be
+ * automatically triggered by a name being unlinked.
+ */
+ INSIST(!result);
+ result = dec_adb_irefcnt(adb);
+ } else {
+ /*
+ * Run through the list. For each name, clean up finds
+ * found there, and cancel any fetches running. When
+ * all the fetches are canceled, the name will destroy
+ * itself.
+ */
+ while (name != NULL) {
+ next_name = ISC_LIST_NEXT(name, plink);
+ INSIST(!result);
+ result = kill_name(&name,
+ DNS_EVENT_ADBSHUTDOWN);
+ name = next_name;
+ }
+ }
+
+ UNLOCK(&adb->namelocks[bucket]);
+ }
+ return (result);
+}
+
+/*
+ * The ADB _MUST_ be locked before calling. Also, exit conditions must be
+ * checked after calling this function.
+ */
+static bool
+shutdown_entries(dns_adb_t *adb) {
+ unsigned int bucket;
+ bool result = false;
+ dns_adbentry_t *entry;
+ dns_adbentry_t *next_entry;
+
+ for (bucket = 0; bucket < adb->nentries; bucket++) {
+ LOCK(&adb->entrylocks[bucket]);
+ adb->entry_sd[bucket] = true;
+
+ entry = ISC_LIST_HEAD(adb->entries[bucket]);
+ if (adb->entry_refcnt[bucket] == 0) {
+ /*
+ * This bucket has no entries. We must decrement the
+ * irefcnt ourselves, since it will not be
+ * automatically triggered by an entry being unlinked.
+ */
+ result = dec_adb_irefcnt(adb);
+ } else {
+ /*
+ * Run through the list. Cleanup any entries not
+ * associated with names, and which are not in use.
+ */
+ while (entry != NULL) {
+ next_entry = ISC_LIST_NEXT(entry, plink);
+ if (entry->refcnt == 0 && entry->expires != 0) {
+ result = unlink_entry(adb, entry);
+ free_adbentry(adb, &entry);
+ if (result) {
+ result = dec_adb_irefcnt(adb);
+ }
+ }
+ entry = next_entry;
+ }
+ }
+
+ UNLOCK(&adb->entrylocks[bucket]);
+ }
+ return (result);
+}
+
+/*
+ * Name bucket must be locked
+ */
+static void
+cancel_fetches_at_name(dns_adbname_t *name) {
+ if (NAME_FETCH_A(name)) {
+ dns_resolver_cancelfetch(name->fetch_a->fetch);
+ }
+
+ if (NAME_FETCH_AAAA(name)) {
+ dns_resolver_cancelfetch(name->fetch_aaaa->fetch);
+ }
+}
+
+/*
+ * Assumes the name bucket is locked.
+ */
+static bool
+clean_namehooks(dns_adb_t *adb, dns_adbnamehooklist_t *namehooks) {
+ dns_adbentry_t *entry;
+ dns_adbnamehook_t *namehook;
+ int addr_bucket;
+ bool result = false;
+ bool overmem = isc_mem_isovermem(adb->mctx);
+
+ addr_bucket = DNS_ADB_INVALIDBUCKET;
+ namehook = ISC_LIST_HEAD(*namehooks);
+ while (namehook != NULL) {
+ INSIST(DNS_ADBNAMEHOOK_VALID(namehook));
+
+ /*
+ * Clean up the entry if needed.
+ */
+ entry = namehook->entry;
+ if (entry != NULL) {
+ INSIST(DNS_ADBENTRY_VALID(entry));
+
+ if (addr_bucket != entry->lock_bucket) {
+ if (addr_bucket != DNS_ADB_INVALIDBUCKET) {
+ UNLOCK(&adb->entrylocks[addr_bucket]);
+ }
+ addr_bucket = entry->lock_bucket;
+ INSIST(addr_bucket != DNS_ADB_INVALIDBUCKET);
+ LOCK(&adb->entrylocks[addr_bucket]);
+ }
+
+ entry->nh--;
+ result = dec_entry_refcnt(adb, overmem, entry, false,
+ INT_MAX);
+ }
+
+ /*
+ * Free the namehook
+ */
+ namehook->entry = NULL;
+ ISC_LIST_UNLINK(*namehooks, namehook, plink);
+ free_adbnamehook(adb, &namehook);
+
+ namehook = ISC_LIST_HEAD(*namehooks);
+ }
+
+ if (addr_bucket != DNS_ADB_INVALIDBUCKET) {
+ UNLOCK(&adb->entrylocks[addr_bucket]);
+ }
+ return (result);
+}
+
+static void
+clean_target(dns_adb_t *adb, dns_name_t *target) {
+ if (dns_name_countlabels(target) > 0) {
+ dns_name_free(target, adb->mctx);
+ dns_name_init(target, NULL);
+ }
+}
+
+static isc_result_t
+set_target(dns_adb_t *adb, const dns_name_t *name, const dns_name_t *fname,
+ dns_rdataset_t *rdataset, dns_name_t *target) {
+ isc_result_t result;
+ dns_namereln_t namereln;
+ unsigned int nlabels;
+ int order;
+ dns_rdata_t rdata = DNS_RDATA_INIT;
+ dns_fixedname_t fixed1, fixed2;
+ dns_name_t *prefix, *new_target;
+
+ REQUIRE(dns_name_countlabels(target) == 0);
+
+ if (rdataset->type == dns_rdatatype_cname) {
+ dns_rdata_cname_t cname;
+
+ /*
+ * Copy the CNAME's target into the target name.
+ */
+ result = dns_rdataset_first(rdataset);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ dns_rdataset_current(rdataset, &rdata);
+ result = dns_rdata_tostruct(&rdata, &cname, NULL);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ dns_name_dup(&cname.cname, adb->mctx, target);
+ dns_rdata_freestruct(&cname);
+ } else {
+ dns_rdata_dname_t dname;
+
+ INSIST(rdataset->type == dns_rdatatype_dname);
+ namereln = dns_name_fullcompare(name, fname, &order, &nlabels);
+ INSIST(namereln == dns_namereln_subdomain);
+ /*
+ * Get the target name of the DNAME.
+ */
+ result = dns_rdataset_first(rdataset);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ dns_rdataset_current(rdataset, &rdata);
+ result = dns_rdata_tostruct(&rdata, &dname, NULL);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ /*
+ * Construct the new target name.
+ */
+ prefix = dns_fixedname_initname(&fixed1);
+ new_target = dns_fixedname_initname(&fixed2);
+ dns_name_split(name, nlabels, prefix, NULL);
+ result = dns_name_concatenate(prefix, &dname.dname, new_target,
+ NULL);
+ dns_rdata_freestruct(&dname);
+ if (result != ISC_R_SUCCESS) {
+ return (result);
+ }
+ dns_name_dup(new_target, adb->mctx, target);
+ }
+
+ return (ISC_R_SUCCESS);
+}
+
+/*
+ * Assumes nothing is locked, since this is called by the client.
+ */
+static void
+event_free(isc_event_t *event) {
+ dns_adbfind_t *find;
+
+ INSIST(event != NULL);
+ find = event->ev_destroy_arg;
+ INSIST(DNS_ADBFIND_VALID(find));
+
+ LOCK(&find->lock);
+ find->flags |= FIND_EVENT_FREED;
+ event->ev_destroy_arg = NULL;
+ UNLOCK(&find->lock);
+}
+
+/*
+ * Assumes the name bucket is locked.
+ */
+static void
+clean_finds_at_name(dns_adbname_t *name, isc_eventtype_t evtype,
+ unsigned int addrs) {
+ isc_event_t *ev;
+ isc_task_t *task;
+ dns_adbfind_t *find;
+ dns_adbfind_t *next_find;
+ bool process;
+ unsigned int wanted, notify;
+
+ DP(ENTER_LEVEL,
+ "ENTER clean_finds_at_name, name %p, evtype %08x, addrs %08x", name,
+ evtype, addrs);
+
+ find = ISC_LIST_HEAD(name->finds);
+ while (find != NULL) {
+ LOCK(&find->lock);
+ next_find = ISC_LIST_NEXT(find, plink);
+
+ process = false;
+ wanted = find->flags & DNS_ADBFIND_ADDRESSMASK;
+ notify = wanted & addrs;
+
+ switch (evtype) {
+ case DNS_EVENT_ADBMOREADDRESSES:
+ DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBMOREADDRESSES");
+ if ((notify) != 0) {
+ find->flags &= ~addrs;
+ process = true;
+ }
+ break;
+ case DNS_EVENT_ADBNOMOREADDRESSES:
+ DP(ISC_LOG_DEBUG(3), "DNS_EVENT_ADBNOMOREADDRESSES");
+ find->flags &= ~addrs;
+ wanted = find->flags & DNS_ADBFIND_ADDRESSMASK;
+ if (wanted == 0) {
+ process = true;
+ }
+ break;
+ default:
+ find->flags &= ~addrs;
+ process = true;
+ }
+
+ if (process) {
+ DP(DEF_LEVEL, "cfan: processing find %p", find);
+ /*
+ * Unlink the find from the name, letting the caller
+ * call dns_adb_destroyfind() on it to clean it up
+ * later.
+ */
+ ISC_LIST_UNLINK(name->finds, find, plink);
+ find->adbname = NULL;
+ find->name_bucket = DNS_ADB_INVALIDBUCKET;
+
+ INSIST(!FIND_EVENTSENT(find));
+
+ ev = &find->event;
+ task = ev->ev_sender;
+ ev->ev_sender = find;
+ find->result_v4 = find_err_map[name->fetch_err];
+ find->result_v6 = find_err_map[name->fetch6_err];
+ ev->ev_type = evtype;
+ ev->ev_destroy = event_free;
+ ev->ev_destroy_arg = find;
+
+ DP(DEF_LEVEL, "sending event %p to task %p for find %p",
+ ev, task, find);
+
+ isc_task_sendanddetach(&task, (isc_event_t **)&ev);
+ find->flags |= FIND_EVENT_SENT;
+ } else {
+ DP(DEF_LEVEL, "cfan: skipping find %p", find);
+ }
+
+ UNLOCK(&find->lock);
+ find = next_find;
+ }
+ DP(ENTER_LEVEL, "EXIT clean_finds_at_name, name %p", name);
+}
+
+static void
+check_exit(dns_adb_t *adb) {
+ isc_event_t *event;
+ /*
+ * The caller must be holding the adb lock.
+ */
+ if (atomic_load(&adb->shutting_down)) {
+ /*
+ * If there aren't any external references either, we're
+ * done. Send the control event to initiate shutdown.
+ */
+ INSIST(!adb->cevent_out); /* Sanity check. */
+ ISC_EVENT_INIT(&adb->cevent, sizeof(adb->cevent), 0, NULL,
+ DNS_EVENT_ADBCONTROL, shutdown_task, adb, adb,
+ NULL, NULL);
+ event = &adb->cevent;
+ isc_task_send(adb->task, &event);
+ adb->cevent_out = true;
+ }
+}
+
+static bool
+dec_adb_irefcnt(dns_adb_t *adb) {
+ isc_event_t *event;
+ isc_task_t *etask;
+ bool result = false;
+
+ LOCK(&adb->reflock);
+
+ INSIST(adb->irefcnt > 0);
+ adb->irefcnt--;
+
+ if (adb->irefcnt == 0) {
+ event = ISC_LIST_HEAD(adb->whenshutdown);
+ while (event != NULL) {
+ ISC_LIST_UNLINK(adb->whenshutdown, event, ev_link);
+ etask = event->ev_sender;
+ event->ev_sender = adb;
+ isc_task_sendanddetach(&etask, &event);
+ event = ISC_LIST_HEAD(adb->whenshutdown);
+ }
+ }
+
+ if (adb->irefcnt == 0 && adb->erefcnt == 0) {
+ result = true;
+ }
+ UNLOCK(&adb->reflock);
+ return (result);
+}
+
+static void
+inc_adb_irefcnt(dns_adb_t *adb) {
+ LOCK(&adb->reflock);
+ adb->irefcnt++;
+ UNLOCK(&adb->reflock);
+}
+
+static void
+inc_adb_erefcnt(dns_adb_t *adb) {
+ LOCK(&adb->reflock);
+ adb->erefcnt++;
+ UNLOCK(&adb->reflock);
+}
+
+static void
+inc_entry_refcnt(dns_adb_t *adb, dns_adbentry_t *entry, bool lock) {
+ int bucket;
+
+ bucket = entry->lock_bucket;
+
+ if (lock) {
+ LOCK(&adb->entrylocks[bucket]);
+ }
+
+ entry->refcnt++;
+
+ if (lock) {
+ UNLOCK(&adb->entrylocks[bucket]);
+ }
+}
+
+static bool
+dec_entry_refcnt(dns_adb_t *adb, bool overmem, dns_adbentry_t *entry, bool lock,
+ isc_stdtime_t now) {
+ int bucket;
+ bool destroy_entry = false;
+ bool result = false;
+
+ bucket = entry->lock_bucket;
+
+ if (lock) {
+ LOCK(&adb->entrylocks[bucket]);
+ }
+
+ INSIST(entry->refcnt > 0);
+ entry->refcnt--;
+
+ if (entry->refcnt == 0 &&
+ (adb->entry_sd[bucket] || entry->expires == 0 ||
+ (overmem && entry->expires + ADB_CACHE_MINIMUM < now) ||
+ (entry->flags & ENTRY_IS_DEAD) != 0))
+ {
+ destroy_entry = true;
+ result = unlink_entry(adb, entry);
+ }
+
+ if (lock) {
+ UNLOCK(&adb->entrylocks[bucket]);
+ }
+
+ if (!destroy_entry) {
+ return (result);
+ }
+
+ entry->lock_bucket = DNS_ADB_INVALIDBUCKET;
+
+ free_adbentry(adb, &entry);
+ if (result) {
+ result = dec_adb_irefcnt(adb);
+ }
+
+ return (result);
+}
+
+static dns_adbname_t *
+new_adbname(dns_adb_t *adb, const dns_name_t *dnsname) {
+ dns_adbname_t *name;
+
+ name = isc_mem_get(adb->mctx, sizeof(*name));
+
+ dns_name_init(&name->name, NULL);
+ dns_name_dup(dnsname, adb->mctx, &name->name);
+ dns_name_init(&name->target, NULL);
+ name->magic = DNS_ADBNAME_MAGIC;
+ name->adb = adb;
+ name->partial_result = 0;
+ name->flags = 0;
+ name->expire_v4 = INT_MAX;
+ name->expire_v6 = INT_MAX;
+ name->expire_target = INT_MAX;
+ name->chains = 0;
+ name->lock_bucket = DNS_ADB_INVALIDBUCKET;
+ ISC_LIST_INIT(name->v4);
+ ISC_LIST_INIT(name->v6);
+ name->fetch_a = NULL;
+ name->fetch_aaaa = NULL;
+ name->fetch_err = FIND_ERR_UNEXPECTED;
+ name->fetch6_err = FIND_ERR_UNEXPECTED;
+ ISC_LIST_INIT(name->finds);
+ ISC_LINK_INIT(name, plink);
+
+ LOCK(&adb->namescntlock);
+ adb->namescnt++;
+ inc_adbstats(adb, dns_adbstats_namescnt);
+ if (!adb->grownames_sent && adb->excl != NULL &&
+ adb->namescnt > (adb->nnames * 8))
+ {
+ isc_event_t *event = &adb->grownames;
+ inc_adb_irefcnt(adb);
+ isc_task_send(adb->excl, &event);
+ adb->grownames_sent = true;
+ }
+ UNLOCK(&adb->namescntlock);
+
+ return (name);
+}
+
+static void
+free_adbname(dns_adb_t *adb, dns_adbname_t **name) {
+ dns_adbname_t *n;
+
+ INSIST(name != NULL && DNS_ADBNAME_VALID(*name));
+ n = *name;
+ *name = NULL;
+
+ INSIST(!NAME_HAS_V4(n));
+ INSIST(!NAME_HAS_V6(n));
+ INSIST(!NAME_FETCH(n));
+ INSIST(ISC_LIST_EMPTY(n->finds));
+ INSIST(!ISC_LINK_LINKED(n, plink));
+ INSIST(n->lock_bucket == DNS_ADB_INVALIDBUCKET);
+ INSIST(n->adb == adb);
+
+ n->magic = 0;
+ dns_name_free(&n->name, adb->mctx);
+
+ isc_mem_put(adb->mctx, n, sizeof(*n));
+ LOCK(&adb->namescntlock);
+ adb->namescnt--;
+ dec_adbstats(adb, dns_adbstats_namescnt);
+ UNLOCK(&adb->namescntlock);
+}
+
+static dns_adbnamehook_t *
+new_adbnamehook(dns_adb_t *adb, dns_adbentry_t *entry) {
+ dns_adbnamehook_t *nh;
+
+ nh = isc_mem_get(adb->mctx, sizeof(*nh));
+ isc_refcount_increment0(&adb->nhrefcnt);
+
+ nh->magic = DNS_ADBNAMEHOOK_MAGIC;
+ nh->entry = entry;
+ ISC_LINK_INIT(nh, plink);
+
+ return (nh);
+}
+
+static void
+free_adbnamehook(dns_adb_t *adb, dns_adbnamehook_t **namehook) {
+ dns_adbnamehook_t *nh;
+
+ INSIST(namehook != NULL && DNS_ADBNAMEHOOK_VALID(*namehook));
+ nh = *namehook;
+ *namehook = NULL;
+
+ INSIST(nh->entry == NULL);
+ INSIST(!ISC_LINK_LINKED(nh, plink));
+
+ nh->magic = 0;
+
+ isc_refcount_decrement(&adb->nhrefcnt);
+ isc_mem_put(adb->mctx, nh, sizeof(*nh));
+}
+
+static dns_adblameinfo_t *
+new_adblameinfo(dns_adb_t *adb, const dns_name_t *qname,
+ dns_rdatatype_t qtype) {
+ dns_adblameinfo_t *li;
+
+ li = isc_mem_get(adb->mctx, sizeof(*li));
+
+ dns_name_init(&li->qname, NULL);
+ dns_name_dup(qname, adb->mctx, &li->qname);
+ li->magic = DNS_ADBLAMEINFO_MAGIC;
+ li->lame_timer = 0;
+ li->qtype = qtype;
+ ISC_LINK_INIT(li, plink);
+
+ return (li);
+}
+
+static void
+free_adblameinfo(dns_adb_t *adb, dns_adblameinfo_t **lameinfo) {
+ dns_adblameinfo_t *li;
+
+ INSIST(lameinfo != NULL && DNS_ADBLAMEINFO_VALID(*lameinfo));
+ li = *lameinfo;
+ *lameinfo = NULL;
+
+ INSIST(!ISC_LINK_LINKED(li, plink));
+
+ dns_name_free(&li->qname, adb->mctx);
+
+ li->magic = 0;
+
+ isc_mem_put(adb->mctx, li, sizeof(*li));
+}
+
+static dns_adbentry_t *
+new_adbentry(dns_adb_t *adb) {
+ dns_adbentry_t *e;
+
+ e = isc_mem_get(adb->mctx, sizeof(*e));
+
+ e->magic = DNS_ADBENTRY_MAGIC;
+ e->lock_bucket = DNS_ADB_INVALIDBUCKET;
+ e->refcnt = 0;
+ e->nh = 0;
+ e->flags = 0;
+ e->udpsize = 0;
+ e->edns = 0;
+ e->ednsto = 0;
+ e->completed = 0;
+ e->timeouts = 0;
+ e->plain = 0;
+ e->plainto = 0;
+ e->cookie = NULL;
+ e->cookielen = 0;
+ e->srtt = (isc_random_uniform(0x1f)) + 1;
+ e->lastage = 0;
+ e->expires = 0;
+ atomic_init(&e->active, 0);
+ e->mode = 0;
+ atomic_init(&e->quota, adb->quota);
+ e->atr = 0.0;
+ ISC_LIST_INIT(e->lameinfo);
+ ISC_LINK_INIT(e, plink);
+ LOCK(&adb->entriescntlock);
+ adb->entriescnt++;
+ inc_adbstats(adb, dns_adbstats_entriescnt);
+ if (!adb->growentries_sent && adb->excl != NULL &&
+ adb->entriescnt > (adb->nentries * 8))
+ {
+ isc_event_t *event = &adb->growentries;
+ inc_adb_irefcnt(adb);
+ isc_task_send(adb->excl, &event);
+ adb->growentries_sent = true;
+ }
+ UNLOCK(&adb->entriescntlock);
+
+ return (e);
+}
+
+static void
+free_adbentry(dns_adb_t *adb, dns_adbentry_t **entry) {
+ dns_adbentry_t *e;
+ dns_adblameinfo_t *li;
+ uint_fast32_t active;
+
+ INSIST(entry != NULL && DNS_ADBENTRY_VALID(*entry));
+ e = *entry;
+ *entry = NULL;
+
+ active = atomic_load_acquire(&e->active);
+ INSIST(active == 0);
+ INSIST(e->lock_bucket == DNS_ADB_INVALIDBUCKET);
+ INSIST(e->refcnt == 0);
+ INSIST(!ISC_LINK_LINKED(e, plink));
+
+ e->magic = 0;
+
+ if (e->cookie != NULL) {
+ isc_mem_put(adb->mctx, e->cookie, e->cookielen);
+ }
+
+ li = ISC_LIST_HEAD(e->lameinfo);
+ while (li != NULL) {
+ ISC_LIST_UNLINK(e->lameinfo, li, plink);
+ free_adblameinfo(adb, &li);
+ li = ISC_LIST_HEAD(e->lameinfo);
+ }
+
+ isc_mem_put(adb->mctx, e, sizeof(*e));
+ LOCK(&adb->entriescntlock);
+ adb->entriescnt--;
+ dec_adbstats(adb, dns_adbstats_entriescnt);
+ UNLOCK(&adb->entriescntlock);
+}
+
+static dns_adbfind_t *
+new_adbfind(dns_adb_t *adb) {
+ dns_adbfind_t *h;
+
+ h = isc_mem_get(adb->mctx, sizeof(*h));
+ isc_refcount_increment0(&adb->ahrefcnt);
+
+ /*
+ * Public members.
+ */
+ h->magic = 0;
+ h->adb = adb;
+ h->partial_result = 0;
+ h->options = 0;
+ h->flags = 0;
+ h->result_v4 = ISC_R_UNEXPECTED;
+ h->result_v6 = ISC_R_UNEXPECTED;
+ ISC_LINK_INIT(h, publink);
+ ISC_LINK_INIT(h, plink);
+ ISC_LIST_INIT(h->list);
+ h->adbname = NULL;
+ h->name_bucket = DNS_ADB_INVALIDBUCKET;
+
+ /*
+ * private members
+ */
+ isc_mutex_init(&h->lock);
+
+ ISC_EVENT_INIT(&h->event, sizeof(isc_event_t), 0, 0, 0, NULL, NULL,
+ NULL, NULL, h);
+
+ inc_adb_irefcnt(adb);
+ h->magic = DNS_ADBFIND_MAGIC;
+ return (h);
+}
+
+static dns_adbfetch_t *
+new_adbfetch(dns_adb_t *adb) {
+ dns_adbfetch_t *f;
+
+ f = isc_mem_get(adb->mctx, sizeof(*f));
+
+ f->magic = 0;
+ f->fetch = NULL;
+
+ dns_rdataset_init(&f->rdataset);
+
+ f->magic = DNS_ADBFETCH_MAGIC;
+
+ return (f);
+}
+
+static void
+free_adbfetch(dns_adb_t *adb, dns_adbfetch_t **fetch) {
+ dns_adbfetch_t *f;
+
+ INSIST(fetch != NULL && DNS_ADBFETCH_VALID(*fetch));
+ f = *fetch;
+ *fetch = NULL;
+
+ f->magic = 0;
+
+ if (dns_rdataset_isassociated(&f->rdataset)) {
+ dns_rdataset_disassociate(&f->rdataset);
+ }
+
+ isc_mem_put(adb->mctx, f, sizeof(*f));
+}
+
+static bool
+free_adbfind(dns_adb_t *adb, dns_adbfind_t **findp) {
+ dns_adbfind_t *find;
+
+ INSIST(findp != NULL && DNS_ADBFIND_VALID(*findp));
+ find = *findp;
+ *findp = NULL;
+
+ INSIST(!FIND_HAS_ADDRS(find));
+ INSIST(!ISC_LINK_LINKED(find, publink));
+ INSIST(!ISC_LINK_LINKED(find, plink));
+ INSIST(find->name_bucket == DNS_ADB_INVALIDBUCKET);
+ INSIST(find->adbname == NULL);
+
+ find->magic = 0;
+
+ isc_mutex_destroy(&find->lock);
+
+ isc_refcount_decrement(&adb->ahrefcnt);
+ isc_mem_put(adb->mctx, find, sizeof(*find));
+ return (dec_adb_irefcnt(adb));
+}
+
+/*
+ * Copy bits from the entry into the newly allocated addrinfo. The entry
+ * must be locked, and the reference count must be bumped up by one
+ * if this function returns a valid pointer.
+ */
+static dns_adbaddrinfo_t *
+new_adbaddrinfo(dns_adb_t *adb, dns_adbentry_t *entry, in_port_t port) {
+ dns_adbaddrinfo_t *ai;
+
+ ai = isc_mem_get(adb->mctx, sizeof(*ai));
+
+ ai->magic = DNS_ADBADDRINFO_MAGIC;
+ ai->sockaddr = entry->sockaddr;
+ isc_sockaddr_setport(&ai->sockaddr, port);
+ ai->srtt = entry->srtt;
+ ai->flags = entry->flags;
+ ai->entry = entry;
+ ISC_LINK_INIT(ai, publink);
+
+ return (ai);
+}
+
+static void
+free_adbaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **ainfo) {
+ dns_adbaddrinfo_t *ai;
+
+ INSIST(ainfo != NULL && DNS_ADBADDRINFO_VALID(*ainfo));
+ ai = *ainfo;
+ *ainfo = NULL;
+
+ INSIST(ai->entry == NULL);
+ INSIST(!ISC_LINK_LINKED(ai, publink));
+
+ ai->magic = 0;
+
+ isc_mem_put(adb->mctx, ai, sizeof(*ai));
+}
+
+/*
+ * Search for the name. NOTE: The bucket is kept locked on both
+ * success and failure, so it must always be unlocked by the caller!
+ *
+ * On the first call to this function, *bucketp must be set to
+ * DNS_ADB_INVALIDBUCKET.
+ */
+static dns_adbname_t *
+find_name_and_lock(dns_adb_t *adb, const dns_name_t *name, unsigned int options,
+ int *bucketp) {
+ dns_adbname_t *adbname;
+ int bucket;
+
+ bucket = dns_name_fullhash(name, false) % adb->nnames;
+
+ if (*bucketp == DNS_ADB_INVALIDBUCKET) {
+ LOCK(&adb->namelocks[bucket]);
+ *bucketp = bucket;
+ } else if (*bucketp != bucket) {
+ UNLOCK(&adb->namelocks[*bucketp]);
+ LOCK(&adb->namelocks[bucket]);
+ *bucketp = bucket;
+ }
+
+ adbname = ISC_LIST_HEAD(adb->names[bucket]);
+ while (adbname != NULL) {
+ if (!NAME_DEAD(adbname)) {
+ if (dns_name_equal(name, &adbname->name) &&
+ GLUEHINT_OK(adbname, options) &&
+ STARTATZONE_MATCHES(adbname, options))
+ {
+ return (adbname);
+ }
+ }
+ adbname = ISC_LIST_NEXT(adbname, plink);
+ }
+
+ return (NULL);
+}
+
+/*
+ * Search for the address. NOTE: The bucket is kept locked on both
+ * success and failure, so it must always be unlocked by the caller.
+ *
+ * On the first call to this function, *bucketp must be set to
+ * DNS_ADB_INVALIDBUCKET. This will cause a lock to occur. On
+ * later calls (within the same "lock path") it can be left alone, so
+ * if this function is called multiple times locking is only done if
+ * the bucket changes.
+ */
+static dns_adbentry_t *
+find_entry_and_lock(dns_adb_t *adb, const isc_sockaddr_t *addr, int *bucketp,
+ isc_stdtime_t now) {
+ dns_adbentry_t *entry, *entry_next;
+ int bucket;
+
+ bucket = isc_sockaddr_hash(addr, true) % adb->nentries;
+
+ if (*bucketp == DNS_ADB_INVALIDBUCKET) {
+ LOCK(&adb->entrylocks[bucket]);
+ *bucketp = bucket;
+ } else if (*bucketp != bucket) {
+ UNLOCK(&adb->entrylocks[*bucketp]);
+ LOCK(&adb->entrylocks[bucket]);
+ *bucketp = bucket;
+ }
+
+ /* Search the list, while cleaning up expired entries. */
+ for (entry = ISC_LIST_HEAD(adb->entries[bucket]); entry != NULL;
+ entry = entry_next)
+ {
+ entry_next = ISC_LIST_NEXT(entry, plink);
+ (void)check_expire_entry(adb, &entry, now);
+ if (entry != NULL &&
+ (entry->expires == 0 || entry->expires > now) &&
+ isc_sockaddr_equal(addr, &entry->sockaddr))
+ {
+ ISC_LIST_UNLINK(adb->entries[bucket], entry, plink);
+ ISC_LIST_PREPEND(adb->entries[bucket], entry, plink);
+ return (entry);
+ }
+ }
+
+ return (NULL);
+}
+
+/*
+ * Entry bucket MUST be locked!
+ */
+static bool
+entry_is_lame(dns_adb_t *adb, dns_adbentry_t *entry, const dns_name_t *qname,
+ dns_rdatatype_t qtype, isc_stdtime_t now) {
+ dns_adblameinfo_t *li, *next_li;
+ bool is_bad;
+
+ is_bad = false;
+
+ li = ISC_LIST_HEAD(entry->lameinfo);
+ if (li == NULL) {
+ return (false);
+ }
+ while (li != NULL) {
+ next_li = ISC_LIST_NEXT(li, plink);
+
+ /*
+ * Has the entry expired?
+ */
+ if (li->lame_timer < now) {
+ ISC_LIST_UNLINK(entry->lameinfo, li, plink);
+ free_adblameinfo(adb, &li);
+ }
+
+ /*
+ * Order tests from least to most expensive.
+ *
+ * We do not break out of the main loop here as
+ * we use the loop for house keeping.
+ */
+ if (li != NULL && !is_bad && li->qtype == qtype &&
+ dns_name_equal(qname, &li->qname))
+ {
+ is_bad = true;
+ }
+
+ li = next_li;
+ }
+
+ return (is_bad);
+}
+
+static void
+log_quota(dns_adbentry_t *entry, const char *fmt, ...) {
+ va_list ap;
+ char msgbuf[2048];
+ char addrbuf[ISC_NETADDR_FORMATSIZE];
+ isc_netaddr_t netaddr;
+
+ va_start(ap, fmt);
+ vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap);
+ va_end(ap);
+
+ isc_netaddr_fromsockaddr(&netaddr, &entry->sockaddr);
+ isc_netaddr_format(&netaddr, addrbuf, sizeof(addrbuf));
+
+ isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB,
+ ISC_LOG_INFO,
+ "adb: quota %s (%" PRIuFAST32 "/%" PRIuFAST32 "): %s",
+ addrbuf, atomic_load_relaxed(&entry->active),
+ atomic_load_relaxed(&entry->quota), msgbuf);
+}
+
+static void
+copy_namehook_lists(dns_adb_t *adb, dns_adbfind_t *find,
+ const dns_name_t *qname, dns_rdatatype_t qtype,
+ dns_adbname_t *name, isc_stdtime_t now) {
+ dns_adbnamehook_t *namehook;
+ dns_adbaddrinfo_t *addrinfo;
+ dns_adbentry_t *entry;
+ int bucket;
+
+ bucket = DNS_ADB_INVALIDBUCKET;
+
+ if ((find->options & DNS_ADBFIND_INET) != 0) {
+ namehook = ISC_LIST_HEAD(name->v4);
+ while (namehook != NULL) {
+ entry = namehook->entry;
+ bucket = entry->lock_bucket;
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+ LOCK(&adb->entrylocks[bucket]);
+
+ if (dns_adbentry_overquota(entry)) {
+ find->options |= (DNS_ADBFIND_LAMEPRUNED |
+ DNS_ADBFIND_OVERQUOTA);
+ goto nextv4;
+ }
+
+ if (!FIND_RETURNLAME(find) &&
+ entry_is_lame(adb, entry, qname, qtype, now))
+ {
+ find->options |= DNS_ADBFIND_LAMEPRUNED;
+ goto nextv4;
+ }
+
+ addrinfo = new_adbaddrinfo(adb, entry, find->port);
+
+ /*
+ * Found a valid entry. Add it to the find's list.
+ */
+ inc_entry_refcnt(adb, entry, false);
+ ISC_LIST_APPEND(find->list, addrinfo, publink);
+ addrinfo = NULL;
+ nextv4:
+ UNLOCK(&adb->entrylocks[bucket]);
+ bucket = DNS_ADB_INVALIDBUCKET;
+ namehook = ISC_LIST_NEXT(namehook, plink);
+ }
+ }
+
+ if ((find->options & DNS_ADBFIND_INET6) != 0) {
+ namehook = ISC_LIST_HEAD(name->v6);
+ while (namehook != NULL) {
+ entry = namehook->entry;
+ bucket = entry->lock_bucket;
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+ LOCK(&adb->entrylocks[bucket]);
+
+ if (dns_adbentry_overquota(entry)) {
+ find->options |= (DNS_ADBFIND_LAMEPRUNED |
+ DNS_ADBFIND_OVERQUOTA);
+ goto nextv6;
+ }
+
+ if (!FIND_RETURNLAME(find) &&
+ entry_is_lame(adb, entry, qname, qtype, now))
+ {
+ find->options |= DNS_ADBFIND_LAMEPRUNED;
+ goto nextv6;
+ }
+ addrinfo = new_adbaddrinfo(adb, entry, find->port);
+
+ /*
+ * Found a valid entry. Add it to the find's list.
+ */
+ inc_entry_refcnt(adb, entry, false);
+ ISC_LIST_APPEND(find->list, addrinfo, publink);
+ addrinfo = NULL;
+ nextv6:
+ UNLOCK(&adb->entrylocks[bucket]);
+ bucket = DNS_ADB_INVALIDBUCKET;
+ namehook = ISC_LIST_NEXT(namehook, plink);
+ }
+ }
+
+ if (bucket != DNS_ADB_INVALIDBUCKET) {
+ UNLOCK(&adb->entrylocks[bucket]);
+ }
+}
+
+static void
+shutdown_task(isc_task_t *task, isc_event_t *ev) {
+ dns_adb_t *adb;
+
+ UNUSED(task);
+
+ adb = ev->ev_arg;
+ INSIST(DNS_ADB_VALID(adb));
+
+ isc_event_free(&ev);
+ /*
+ * Wait for lock around check_exit() call to be released.
+ */
+ LOCK(&adb->lock);
+ UNLOCK(&adb->lock);
+ destroy(adb);
+}
+
+/*
+ * Name bucket must be locked; adb may be locked; no other locks held.
+ */
+static bool
+check_expire_name(dns_adbname_t **namep, isc_stdtime_t now) {
+ dns_adbname_t *name;
+ bool result = false;
+
+ INSIST(namep != NULL && DNS_ADBNAME_VALID(*namep));
+ name = *namep;
+
+ if (NAME_HAS_V4(name) || NAME_HAS_V6(name)) {
+ return (result);
+ }
+ if (NAME_FETCH(name)) {
+ return (result);
+ }
+ if (!EXPIRE_OK(name->expire_v4, now)) {
+ return (result);
+ }
+ if (!EXPIRE_OK(name->expire_v6, now)) {
+ return (result);
+ }
+ if (!EXPIRE_OK(name->expire_target, now)) {
+ return (result);
+ }
+
+ /*
+ * The name is empty. Delete it.
+ */
+ *namep = NULL;
+ result = kill_name(&name, DNS_EVENT_ADBEXPIRED);
+
+ /*
+ * Our caller, or one of its callers, will be calling check_exit() at
+ * some point, so we don't need to do it here.
+ */
+ return (result);
+}
+
+/*%
+ * Examine the tail entry of the LRU list to see if it expires or is stale
+ * (unused for some period); if so, the name entry will be freed. If the ADB
+ * is in the overmem condition, the tail and the next to tail entries
+ * will be unconditionally removed (unless they have an outstanding fetch).
+ * We don't care about a race on 'overmem' at the risk of causing some
+ * collateral damage or a small delay in starting cleanup, so we don't bother
+ * to lock ADB (if it's not locked).
+ *
+ * Name bucket must be locked; adb may be locked; no other locks held.
+ */
+static void
+check_stale_name(dns_adb_t *adb, int bucket, isc_stdtime_t now) {
+ int victims, max_victims;
+ dns_adbname_t *victim, *next_victim;
+ bool overmem = isc_mem_isovermem(adb->mctx);
+ int scans = 0;
+
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+
+ max_victims = overmem ? 2 : 1;
+
+ /*
+ * We limit the number of scanned entries to 10 (arbitrary choice)
+ * in order to avoid examining too many entries when there are many
+ * tail entries that have fetches (this should be rare, but could
+ * happen).
+ */
+ victim = ISC_LIST_TAIL(adb->names[bucket]);
+ for (victims = 0; victim != NULL && victims < max_victims && scans < 10;
+ victim = next_victim)
+ {
+ INSIST(!NAME_DEAD(victim));
+ scans++;
+ next_victim = ISC_LIST_PREV(victim, plink);
+ (void)check_expire_name(&victim, now);
+ if (victim == NULL) {
+ victims++;
+ goto next;
+ }
+
+ /*
+ * Make sure that we are not purging ADB names that has been
+ * just created.
+ */
+ if (victim->last_used + ADB_CACHE_MINIMUM >= now) {
+ break;
+ }
+
+ if (!NAME_FETCH(victim) &&
+ (overmem || victim->last_used + ADB_STALE_MARGIN <= now))
+ {
+ RUNTIME_CHECK(
+ !kill_name(&victim, DNS_EVENT_ADBCANCELED));
+ victims++;
+ }
+
+ next:
+ if (!overmem) {
+ break;
+ }
+ }
+}
+
+/*
+ * Entry bucket must be locked; adb may be locked; no other locks held.
+ */
+static bool
+check_expire_entry(dns_adb_t *adb, dns_adbentry_t **entryp, isc_stdtime_t now) {
+ dns_adbentry_t *entry;
+ bool result = false;
+
+ INSIST(entryp != NULL && DNS_ADBENTRY_VALID(*entryp));
+ entry = *entryp;
+
+ if (entry->refcnt != 0) {
+ return (result);
+ }
+
+ if (entry->expires == 0 || entry->expires > now) {
+ return (result);
+ }
+
+ /*
+ * The entry is not in use. Delete it.
+ */
+ *entryp = NULL;
+ DP(DEF_LEVEL, "killing entry %p", entry);
+ INSIST(ISC_LINK_LINKED(entry, plink));
+ result = unlink_entry(adb, entry);
+ free_adbentry(adb, &entry);
+ if (result) {
+ dec_adb_irefcnt(adb);
+ }
+ return (result);
+}
+
+/*
+ * ADB must be locked, and no other locks held.
+ */
+static bool
+cleanup_names(dns_adb_t *adb, int bucket, isc_stdtime_t now) {
+ dns_adbname_t *name;
+ dns_adbname_t *next_name;
+ bool result = false;
+
+ DP(CLEAN_LEVEL, "cleaning name bucket %d", bucket);
+
+ LOCK(&adb->namelocks[bucket]);
+ if (adb->name_sd[bucket]) {
+ UNLOCK(&adb->namelocks[bucket]);
+ return (result);
+ }
+
+ name = ISC_LIST_HEAD(adb->names[bucket]);
+ while (name != NULL) {
+ next_name = ISC_LIST_NEXT(name, plink);
+ INSIST(!result);
+ result = check_expire_namehooks(name, now);
+ if (!result) {
+ result = check_expire_name(&name, now);
+ }
+ name = next_name;
+ }
+ UNLOCK(&adb->namelocks[bucket]);
+ return (result);
+}
+
+/*
+ * ADB must be locked, and no other locks held.
+ */
+static bool
+cleanup_entries(dns_adb_t *adb, int bucket, isc_stdtime_t now) {
+ dns_adbentry_t *entry, *next_entry;
+ bool result = false;
+
+ DP(CLEAN_LEVEL, "cleaning entry bucket %d", bucket);
+
+ LOCK(&adb->entrylocks[bucket]);
+ entry = ISC_LIST_HEAD(adb->entries[bucket]);
+ while (entry != NULL) {
+ next_entry = ISC_LIST_NEXT(entry, plink);
+ INSIST(!result);
+ result = check_expire_entry(adb, &entry, now);
+ entry = next_entry;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+ return (result);
+}
+
+static void
+destroy(dns_adb_t *adb) {
+ adb->magic = 0;
+
+ isc_task_detach(&adb->task);
+ if (adb->excl != NULL) {
+ isc_task_detach(&adb->excl);
+ }
+
+ isc_mutexblock_destroy(adb->entrylocks, adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entries,
+ sizeof(*adb->entries) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->deadentries,
+ sizeof(*adb->deadentries) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entrylocks,
+ sizeof(*adb->entrylocks) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entry_sd,
+ sizeof(*adb->entry_sd) * adb->nentries);
+ isc_mem_put(adb->hmctx, adb->entry_refcnt,
+ sizeof(*adb->entry_refcnt) * adb->nentries);
+
+ isc_mutexblock_destroy(adb->namelocks, adb->nnames);
+ isc_mem_put(adb->hmctx, adb->names, sizeof(*adb->names) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->deadnames,
+ sizeof(*adb->deadnames) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->namelocks,
+ sizeof(*adb->namelocks) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->name_sd,
+ sizeof(*adb->name_sd) * adb->nnames);
+ isc_mem_put(adb->hmctx, adb->name_refcnt,
+ sizeof(*adb->name_refcnt) * adb->nnames);
+
+ isc_mem_destroy(&adb->hmctx);
+
+ isc_mutex_destroy(&adb->reflock);
+ isc_mutex_destroy(&adb->lock);
+ isc_mutex_destroy(&adb->overmemlock);
+ isc_mutex_destroy(&adb->entriescntlock);
+ isc_mutex_destroy(&adb->namescntlock);
+
+ isc_mem_putanddetach(&adb->mctx, adb, sizeof(dns_adb_t));
+}
+
+/*
+ * Public functions.
+ */
+
+isc_result_t
+dns_adb_create(isc_mem_t *mem, dns_view_t *view, isc_timermgr_t *timermgr,
+ isc_taskmgr_t *taskmgr, dns_adb_t **newadb) {
+ dns_adb_t *adb;
+ isc_result_t result;
+ unsigned int i;
+
+ REQUIRE(mem != NULL);
+ REQUIRE(view != NULL);
+ REQUIRE(timermgr != NULL); /* this is actually unused */
+ REQUIRE(taskmgr != NULL);
+ REQUIRE(newadb != NULL && *newadb == NULL);
+
+ UNUSED(timermgr);
+
+ adb = isc_mem_get(mem, sizeof(dns_adb_t));
+
+ /*
+ * Initialize things here that cannot fail, and especially things
+ * that must be NULL for the error return to work properly.
+ */
+ adb->magic = 0;
+ adb->erefcnt = 1;
+ adb->irefcnt = 0;
+ adb->task = NULL;
+ adb->excl = NULL;
+ adb->mctx = NULL;
+ adb->hmctx = NULL;
+ adb->view = view;
+ adb->taskmgr = taskmgr;
+ adb->next_cleanbucket = 0;
+ ISC_EVENT_INIT(&adb->cevent, sizeof(adb->cevent), 0, NULL, 0, NULL,
+ NULL, NULL, NULL, NULL);
+ adb->cevent_out = false;
+ atomic_init(&adb->shutting_down, false);
+ ISC_LIST_INIT(adb->whenshutdown);
+
+ adb->nentries = nbuckets[0];
+ adb->entriescnt = 0;
+ adb->entries = NULL;
+ adb->deadentries = NULL;
+ adb->entry_sd = NULL;
+ adb->entry_refcnt = NULL;
+ adb->entrylocks = NULL;
+ ISC_EVENT_INIT(&adb->growentries, sizeof(adb->growentries), 0, NULL,
+ DNS_EVENT_ADBGROWENTRIES, grow_entries, adb, adb, NULL,
+ NULL);
+ adb->growentries_sent = false;
+
+ adb->quota = 0;
+ adb->atr_freq = 0;
+ adb->atr_low = 0.0;
+ adb->atr_high = 0.0;
+ adb->atr_discount = 0.0;
+
+ adb->nnames = nbuckets[0];
+ adb->namescnt = 0;
+ adb->names = NULL;
+ adb->deadnames = NULL;
+ adb->name_sd = NULL;
+ adb->name_refcnt = NULL;
+ adb->namelocks = NULL;
+ ISC_EVENT_INIT(&adb->grownames, sizeof(adb->grownames), 0, NULL,
+ DNS_EVENT_ADBGROWNAMES, grow_names, adb, adb, NULL,
+ NULL);
+ adb->grownames_sent = false;
+
+ result = isc_taskmgr_excltask(adb->taskmgr, &adb->excl);
+ if (result != ISC_R_SUCCESS) {
+ DP(DEF_LEVEL,
+ "adb: task-exclusive mode unavailable, "
+ "initializing table sizes to %u\n",
+ nbuckets[11]);
+ adb->nentries = nbuckets[11];
+ adb->nnames = nbuckets[11];
+ }
+
+ isc_mem_attach(mem, &adb->mctx);
+
+ isc_mutex_init(&adb->lock);
+ isc_mutex_init(&adb->reflock);
+ isc_mutex_init(&adb->overmemlock);
+ isc_mutex_init(&adb->entriescntlock);
+ isc_mutex_init(&adb->namescntlock);
+
+ isc_mem_create(&adb->hmctx);
+ isc_mem_setname(adb->hmctx, "ADB_hashmaps");
+
+#define ALLOCENTRY(adb, el) \
+ do { \
+ (adb)->el = isc_mem_get((adb)->hmctx, \
+ sizeof(*(adb)->el) * (adb)->nentries); \
+ } while (0)
+ ALLOCENTRY(adb, entries);
+ ALLOCENTRY(adb, deadentries);
+ ALLOCENTRY(adb, entrylocks);
+ ALLOCENTRY(adb, entry_sd);
+ ALLOCENTRY(adb, entry_refcnt);
+#undef ALLOCENTRY
+
+#define ALLOCNAME(adb, el) \
+ do { \
+ (adb)->el = isc_mem_get((adb)->hmctx, \
+ sizeof(*(adb)->el) * (adb)->nnames); \
+ } while (0)
+ ALLOCNAME(adb, names);
+ ALLOCNAME(adb, deadnames);
+ ALLOCNAME(adb, namelocks);
+ ALLOCNAME(adb, name_sd);
+ ALLOCNAME(adb, name_refcnt);
+#undef ALLOCNAME
+
+ /*
+ * Initialize the bucket locks for names and elements.
+ * May as well initialize the list heads, too.
+ */
+ isc_mutexblock_init(adb->namelocks, adb->nnames);
+
+ for (i = 0; i < adb->nnames; i++) {
+ ISC_LIST_INIT(adb->names[i]);
+ ISC_LIST_INIT(adb->deadnames[i]);
+ adb->name_sd[i] = false;
+ adb->name_refcnt[i] = 0;
+ adb->irefcnt++;
+ }
+ for (i = 0; i < adb->nentries; i++) {
+ ISC_LIST_INIT(adb->entries[i]);
+ ISC_LIST_INIT(adb->deadentries[i]);
+ adb->entry_sd[i] = false;
+ adb->entry_refcnt[i] = 0;
+ adb->irefcnt++;
+ }
+ isc_mutexblock_init(adb->entrylocks, adb->nentries);
+
+ isc_refcount_init(&adb->ahrefcnt, 0);
+ isc_refcount_init(&adb->nhrefcnt, 0);
+
+ /*
+ * Allocate an internal task.
+ */
+ result = isc_task_create(adb->taskmgr, 0, &adb->task);
+ if (result != ISC_R_SUCCESS) {
+ goto fail2;
+ }
+
+ isc_task_setname(adb->task, "ADB", adb);
+
+ result = isc_stats_create(adb->mctx, &view->adbstats, dns_adbstats_max);
+ if (result != ISC_R_SUCCESS) {
+ goto fail2;
+ }
+
+ set_adbstat(adb, adb->nentries, dns_adbstats_nentries);
+ set_adbstat(adb, adb->nnames, dns_adbstats_nnames);
+
+ /*
+ * Normal return.
+ */
+ adb->magic = DNS_ADB_MAGIC;
+ *newadb = adb;
+ return (ISC_R_SUCCESS);
+
+fail2:
+ if (adb->task != NULL) {
+ isc_task_detach(&adb->task);
+ }
+
+ /* clean up entrylocks */
+ isc_mutexblock_destroy(adb->entrylocks, adb->nentries);
+ isc_mutexblock_destroy(adb->namelocks, adb->nnames);
+
+ if (adb->entries != NULL) {
+ isc_mem_put(adb->hmctx, adb->entries,
+ sizeof(*adb->entries) * adb->nentries);
+ }
+ if (adb->deadentries != NULL) {
+ isc_mem_put(adb->hmctx, adb->deadentries,
+ sizeof(*adb->deadentries) * adb->nentries);
+ }
+ if (adb->entrylocks != NULL) {
+ isc_mem_put(adb->hmctx, adb->entrylocks,
+ sizeof(*adb->entrylocks) * adb->nentries);
+ }
+ if (adb->entry_sd != NULL) {
+ isc_mem_put(adb->hmctx, adb->entry_sd,
+ sizeof(*adb->entry_sd) * adb->nentries);
+ }
+ if (adb->entry_refcnt != NULL) {
+ isc_mem_put(adb->hmctx, adb->entry_refcnt,
+ sizeof(*adb->entry_refcnt) * adb->nentries);
+ }
+ if (adb->names != NULL) {
+ isc_mem_put(adb->hmctx, adb->names,
+ sizeof(*adb->names) * adb->nnames);
+ }
+ if (adb->deadnames != NULL) {
+ isc_mem_put(adb->hmctx, adb->deadnames,
+ sizeof(*adb->deadnames) * adb->nnames);
+ }
+ if (adb->namelocks != NULL) {
+ isc_mem_put(adb->hmctx, adb->namelocks,
+ sizeof(*adb->namelocks) * adb->nnames);
+ }
+ if (adb->name_sd != NULL) {
+ isc_mem_put(adb->hmctx, adb->name_sd,
+ sizeof(*adb->name_sd) * adb->nnames);
+ }
+ if (adb->name_refcnt != NULL) {
+ isc_mem_put(adb->hmctx, adb->name_refcnt,
+ sizeof(*adb->name_refcnt) * adb->nnames);
+ }
+
+ isc_mem_destroy(&adb->hmctx);
+
+ isc_mutex_destroy(&adb->namescntlock);
+ isc_mutex_destroy(&adb->entriescntlock);
+ isc_mutex_destroy(&adb->overmemlock);
+ isc_mutex_destroy(&adb->reflock);
+ isc_mutex_destroy(&adb->lock);
+ if (adb->excl != NULL) {
+ isc_task_detach(&adb->excl);
+ }
+ isc_mem_putanddetach(&adb->mctx, adb, sizeof(dns_adb_t));
+
+ return (result);
+}
+
+void
+dns_adb_attach(dns_adb_t *adb, dns_adb_t **adbx) {
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(adbx != NULL && *adbx == NULL);
+
+ inc_adb_erefcnt(adb);
+ *adbx = adb;
+}
+
+void
+dns_adb_detach(dns_adb_t **adbx) {
+ dns_adb_t *adb;
+ bool need_exit_check;
+
+ REQUIRE(adbx != NULL && DNS_ADB_VALID(*adbx));
+
+ adb = *adbx;
+ *adbx = NULL;
+
+ LOCK(&adb->reflock);
+ INSIST(adb->erefcnt > 0);
+ adb->erefcnt--;
+ need_exit_check = (adb->erefcnt == 0 && adb->irefcnt == 0);
+ UNLOCK(&adb->reflock);
+
+ if (need_exit_check) {
+ LOCK(&adb->lock);
+ INSIST(atomic_load(&adb->shutting_down));
+ check_exit(adb);
+ UNLOCK(&adb->lock);
+ }
+}
+
+void
+dns_adb_whenshutdown(dns_adb_t *adb, isc_task_t *task, isc_event_t **eventp) {
+ isc_task_t *tclone;
+ isc_event_t *event;
+ bool zeroirefcnt;
+
+ /*
+ * Send '*eventp' to 'task' when 'adb' has shutdown.
+ */
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(eventp != NULL);
+
+ event = *eventp;
+ *eventp = NULL;
+
+ LOCK(&adb->lock);
+ LOCK(&adb->reflock);
+
+ zeroirefcnt = (adb->irefcnt == 0);
+
+ if (atomic_load(&adb->shutting_down) && zeroirefcnt &&
+ isc_refcount_current(&adb->ahrefcnt) == 0)
+ {
+ /*
+ * We're already shutdown. Send the event.
+ */
+ event->ev_sender = adb;
+ isc_task_send(task, &event);
+ } else {
+ tclone = NULL;
+ isc_task_attach(task, &tclone);
+ event->ev_sender = tclone;
+ ISC_LIST_APPEND(adb->whenshutdown, event, ev_link);
+ }
+
+ UNLOCK(&adb->reflock);
+ UNLOCK(&adb->lock);
+}
+
+static void
+shutdown_stage2(isc_task_t *task, isc_event_t *event) {
+ dns_adb_t *adb;
+
+ UNUSED(task);
+
+ adb = event->ev_arg;
+ INSIST(DNS_ADB_VALID(adb));
+
+ LOCK(&adb->lock);
+ INSIST(atomic_load(&adb->shutting_down));
+ adb->cevent_out = false;
+ (void)shutdown_names(adb);
+ (void)shutdown_entries(adb);
+ if (dec_adb_irefcnt(adb)) {
+ check_exit(adb);
+ }
+ UNLOCK(&adb->lock);
+}
+
+void
+dns_adb_shutdown(dns_adb_t *adb) {
+ isc_event_t *event;
+
+ /*
+ * Shutdown 'adb'.
+ */
+
+ LOCK(&adb->lock);
+
+ if (atomic_compare_exchange_strong(&adb->shutting_down,
+ &(bool){ false }, true))
+ {
+ isc_mem_clearwater(adb->mctx);
+ /*
+ * Isolate shutdown_names and shutdown_entries calls.
+ */
+ inc_adb_irefcnt(adb);
+ ISC_EVENT_INIT(&adb->cevent, sizeof(adb->cevent), 0, NULL,
+ DNS_EVENT_ADBCONTROL, shutdown_stage2, adb, adb,
+ NULL, NULL);
+ adb->cevent_out = true;
+ event = &adb->cevent;
+ isc_task_send(adb->task, &event);
+ }
+
+ UNLOCK(&adb->lock);
+}
+
+isc_result_t
+dns_adb_createfind(dns_adb_t *adb, isc_task_t *task, isc_taskaction_t action,
+ void *arg, const dns_name_t *name, const dns_name_t *qname,
+ dns_rdatatype_t qtype, unsigned int options,
+ isc_stdtime_t now, dns_name_t *target, in_port_t port,
+ unsigned int depth, isc_counter_t *qc,
+ dns_adbfind_t **findp) {
+ dns_adbfind_t *find = NULL;
+ dns_adbname_t *adbname = NULL;
+ int bucket;
+ bool want_event = true;
+ bool start_at_zone = false;
+ bool alias = false;
+ bool have_address = false;
+ isc_result_t result;
+ unsigned int wanted_addresses = (options & DNS_ADBFIND_ADDRESSMASK);
+ unsigned int wanted_fetches = 0;
+ unsigned int query_pending = 0;
+ char namebuf[DNS_NAME_FORMATSIZE];
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ if (task != NULL) {
+ REQUIRE(action != NULL);
+ }
+ REQUIRE(name != NULL);
+ REQUIRE(qname != NULL);
+ REQUIRE(findp != NULL && *findp == NULL);
+ REQUIRE(target == NULL || dns_name_hasbuffer(target));
+
+ REQUIRE((options & DNS_ADBFIND_ADDRESSMASK) != 0);
+
+ result = ISC_R_UNEXPECTED;
+ POST(result);
+
+ if (atomic_load(&adb->shutting_down)) {
+ DP(DEF_LEVEL, "dns_adb_createfind: returning "
+ "ISC_R_SHUTTINGDOWN");
+
+ return (ISC_R_SHUTTINGDOWN);
+ }
+
+ if (now == 0) {
+ isc_stdtime_get(&now);
+ }
+
+ /*
+ * XXXMLG Move this comment somewhere else!
+ *
+ * Look up the name in our internal database.
+ *
+ * Possibilities: Note that these are not always exclusive.
+ *
+ * No name found. In this case, allocate a new name header and
+ * an initial namehook or two.
+ *
+ * Name found, valid addresses present. Allocate one addrinfo
+ * structure for each found and append it to the linked list
+ * of addresses for this header.
+ *
+ * Name found, queries pending. In this case, if a task was
+ * passed in, allocate a job id, attach it to the name's job
+ * list and remember to tell the caller that there will be
+ * more info coming later.
+ */
+
+ find = new_adbfind(adb);
+
+ find->port = port;
+
+ /*
+ * Remember what types of addresses we are interested in.
+ */
+ find->options = options;
+ find->flags |= wanted_addresses;
+ if (FIND_WANTEVENT(find)) {
+ REQUIRE(task != NULL);
+ }
+
+ if (isc_log_wouldlog(dns_lctx, DEF_LEVEL)) {
+ dns_name_format(name, namebuf, sizeof(namebuf));
+ } else {
+ namebuf[0] = 0;
+ }
+
+ /*
+ * Try to see if we know anything about this name at all.
+ */
+ bucket = DNS_ADB_INVALIDBUCKET;
+ adbname = find_name_and_lock(adb, name, find->options, &bucket);
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+ if (adb->name_sd[bucket]) {
+ DP(DEF_LEVEL, "dns_adb_createfind: returning "
+ "ISC_R_SHUTTINGDOWN");
+ RUNTIME_CHECK(!free_adbfind(adb, &find));
+ result = ISC_R_SHUTTINGDOWN;
+ goto out;
+ }
+
+ /*
+ * Nothing found. Allocate a new adbname structure for this name.
+ */
+ if (adbname == NULL) {
+ /*
+ * See if there is any stale name at the end of list, and purge
+ * it if so.
+ */
+ check_stale_name(adb, bucket, now);
+
+ adbname = new_adbname(adb, name);
+ link_name(adb, bucket, adbname);
+ if (FIND_HINTOK(find)) {
+ adbname->flags |= DNS_ADBFIND_HINTOK;
+ }
+ if (FIND_GLUEOK(find)) {
+ adbname->flags |= DNS_ADBFIND_GLUEOK;
+ }
+ if (FIND_STARTATZONE(find)) {
+ adbname->flags |= DNS_ADBFIND_STARTATZONE;
+ }
+ } else {
+ /* Move this name forward in the LRU list */
+ ISC_LIST_UNLINK(adb->names[bucket], adbname, plink);
+ ISC_LIST_PREPEND(adb->names[bucket], adbname, plink);
+ }
+ adbname->last_used = now;
+
+ /*
+ * Expire old entries, etc.
+ */
+ RUNTIME_CHECK(!check_expire_namehooks(adbname, now));
+
+ /*
+ * Do we know that the name is an alias?
+ */
+ if (!EXPIRE_OK(adbname->expire_target, now)) {
+ /*
+ * Yes, it is.
+ */
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: name %s (%p) is an alias (cached)",
+ namebuf, adbname);
+ alias = true;
+ goto post_copy;
+ }
+
+ /*
+ * Try to populate the name from the database and/or
+ * start fetches. First try looking for an A record
+ * in the database.
+ */
+ if (!NAME_HAS_V4(adbname) && EXPIRE_OK(adbname->expire_v4, now) &&
+ WANT_INET(wanted_addresses))
+ {
+ result = dbfind_name(adbname, now, dns_rdatatype_a);
+ if (result == ISC_R_SUCCESS) {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: found A for name %s (%p) in db",
+ namebuf, adbname);
+ goto v6;
+ }
+
+ /*
+ * Did we get a CNAME or DNAME?
+ */
+ if (result == DNS_R_ALIAS) {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: name %s (%p) is an alias",
+ namebuf, adbname);
+ alias = true;
+ goto post_copy;
+ }
+
+ /*
+ * If the name doesn't exist at all, don't bother with
+ * v6 queries; they won't work.
+ *
+ * If the name does exist but we didn't get our data, go
+ * ahead and try AAAA.
+ *
+ * If the result is neither of these, try a fetch for A.
+ */
+ if (NXDOMAIN_RESULT(result)) {
+ goto fetch;
+ } else if (NXRRSET_RESULT(result)) {
+ goto v6;
+ }
+
+ if (!NAME_FETCH_A(adbname)) {
+ wanted_fetches |= DNS_ADBFIND_INET;
+ }
+ }
+
+v6:
+ if (!NAME_HAS_V6(adbname) && EXPIRE_OK(adbname->expire_v6, now) &&
+ WANT_INET6(wanted_addresses))
+ {
+ result = dbfind_name(adbname, now, dns_rdatatype_aaaa);
+ if (result == ISC_R_SUCCESS) {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: found AAAA for name %s (%p)",
+ namebuf, adbname);
+ goto fetch;
+ }
+
+ /*
+ * Did we get a CNAME or DNAME?
+ */
+ if (result == DNS_R_ALIAS) {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: name %s (%p) is an alias",
+ namebuf, adbname);
+ alias = true;
+ goto post_copy;
+ }
+
+ /*
+ * Listen to negative cache hints, and don't start
+ * another query.
+ */
+ if (NCACHE_RESULT(result) || AUTH_NX(result)) {
+ goto fetch;
+ }
+
+ if (!NAME_FETCH_AAAA(adbname)) {
+ wanted_fetches |= DNS_ADBFIND_INET6;
+ }
+ }
+
+fetch:
+ if ((WANT_INET(wanted_addresses) && NAME_HAS_V4(adbname)) ||
+ (WANT_INET6(wanted_addresses) && NAME_HAS_V6(adbname)))
+ {
+ have_address = true;
+ } else {
+ have_address = false;
+ }
+ if (wanted_fetches != 0 && !(FIND_AVOIDFETCHES(find) && have_address) &&
+ !FIND_NOFETCH(find))
+ {
+ /*
+ * We're missing at least one address family. Either the
+ * caller hasn't instructed us to avoid fetches, or we don't
+ * know anything about any of the address families that would
+ * be acceptable so we have to launch fetches.
+ */
+
+ if (FIND_STARTATZONE(find)) {
+ start_at_zone = true;
+ }
+
+ /*
+ * Start V4.
+ */
+ if (WANT_INET(wanted_fetches) &&
+ fetch_name(adbname, start_at_zone, depth, qc,
+ dns_rdatatype_a) == ISC_R_SUCCESS)
+ {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: "
+ "started A fetch for name %s (%p)",
+ namebuf, adbname);
+ }
+
+ /*
+ * Start V6.
+ */
+ if (WANT_INET6(wanted_fetches) &&
+ fetch_name(adbname, start_at_zone, depth, qc,
+ dns_rdatatype_aaaa) == ISC_R_SUCCESS)
+ {
+ DP(DEF_LEVEL,
+ "dns_adb_createfind: "
+ "started AAAA fetch for name %s (%p)",
+ namebuf, adbname);
+ }
+ }
+
+ /*
+ * Run through the name and copy out the bits we are
+ * interested in.
+ */
+ copy_namehook_lists(adb, find, qname, qtype, adbname, now);
+
+post_copy:
+ if (NAME_FETCH_A(adbname)) {
+ query_pending |= DNS_ADBFIND_INET;
+ }
+ if (NAME_FETCH_AAAA(adbname)) {
+ query_pending |= DNS_ADBFIND_INET6;
+ }
+
+ /*
+ * Attach to the name's query list if there are queries
+ * already running, and we have been asked to.
+ */
+ if (!FIND_WANTEVENT(find)) {
+ want_event = false;
+ }
+ if (FIND_WANTEMPTYEVENT(find) && FIND_HAS_ADDRS(find)) {
+ want_event = false;
+ }
+ if ((wanted_addresses & query_pending) == 0) {
+ want_event = false;
+ }
+ if (alias) {
+ want_event = false;
+ }
+ if (want_event) {
+ bool empty;
+ find->adbname = adbname;
+ find->name_bucket = bucket;
+ empty = ISC_LIST_EMPTY(adbname->finds);
+ ISC_LIST_APPEND(adbname->finds, find, plink);
+ find->query_pending = (query_pending & wanted_addresses);
+ find->flags &= ~DNS_ADBFIND_ADDRESSMASK;
+ find->flags |= (find->query_pending & DNS_ADBFIND_ADDRESSMASK);
+ DP(DEF_LEVEL, "createfind: attaching find %p to adbname %p %d",
+ find, adbname, empty);
+ } else {
+ /*
+ * Remove the flag so the caller knows there will never
+ * be an event, and set internal flags to fake that
+ * the event was sent and freed, so dns_adb_destroyfind() will
+ * do the right thing.
+ */
+ find->query_pending = (query_pending & wanted_addresses);
+ find->options &= ~DNS_ADBFIND_WANTEVENT;
+ find->flags |= (FIND_EVENT_SENT | FIND_EVENT_FREED);
+ find->flags &= ~DNS_ADBFIND_ADDRESSMASK;
+ }
+
+ find->partial_result |= (adbname->partial_result & wanted_addresses);
+ if (alias) {
+ if (target != NULL) {
+ dns_name_copy(&adbname->target, target);
+ }
+ result = DNS_R_ALIAS;
+ } else {
+ result = ISC_R_SUCCESS;
+ }
+
+ /*
+ * Copy out error flags from the name structure into the find.
+ */
+ find->result_v4 = find_err_map[adbname->fetch_err];
+ find->result_v6 = find_err_map[adbname->fetch6_err];
+
+out:
+ if (find != NULL) {
+ if (want_event) {
+ isc_task_t *taskp = NULL;
+
+ INSIST((find->flags & DNS_ADBFIND_ADDRESSMASK) != 0);
+ isc_task_attach(task, &taskp);
+ find->event.ev_sender = taskp;
+ find->event.ev_action = action;
+ find->event.ev_arg = arg;
+ }
+
+ *findp = find;
+ }
+
+ UNLOCK(&adb->namelocks[bucket]);
+ return (result);
+}
+
+void
+dns_adb_destroyfind(dns_adbfind_t **findp) {
+ dns_adbfind_t *find;
+ dns_adbentry_t *entry;
+ dns_adbaddrinfo_t *ai;
+ int bucket;
+ dns_adb_t *adb;
+ bool overmem;
+ isc_stdtime_t now;
+
+ REQUIRE(findp != NULL && DNS_ADBFIND_VALID(*findp));
+ find = *findp;
+ *findp = NULL;
+
+ LOCK(&find->lock);
+
+ DP(DEF_LEVEL, "dns_adb_destroyfind on find %p", find);
+
+ adb = find->adb;
+ REQUIRE(DNS_ADB_VALID(adb));
+
+ REQUIRE(FIND_EVENTFREED(find));
+
+ bucket = find->name_bucket;
+ INSIST(bucket == DNS_ADB_INVALIDBUCKET);
+
+ UNLOCK(&find->lock);
+
+ /*
+ * The find doesn't exist on any list, and nothing is locked.
+ * Return the find to the memory pool, and decrement the adb's
+ * reference count.
+ */
+ isc_stdtime_get(&now);
+ overmem = isc_mem_isovermem(adb->mctx);
+ ai = ISC_LIST_HEAD(find->list);
+ while (ai != NULL) {
+ ISC_LIST_UNLINK(find->list, ai, publink);
+ entry = ai->entry;
+ ai->entry = NULL;
+ INSIST(DNS_ADBENTRY_VALID(entry));
+ RUNTIME_CHECK(
+ !dec_entry_refcnt(adb, overmem, entry, true, now));
+ free_adbaddrinfo(adb, &ai);
+ ai = ISC_LIST_HEAD(find->list);
+ }
+
+ /*
+ * WARNING: The find is freed with the adb locked. This is done
+ * to avoid a race condition where we free the find, some other
+ * thread tests to see if it should be destroyed, detects it should
+ * be, destroys it, and then we try to lock it for our check, but the
+ * lock is destroyed.
+ */
+ LOCK(&adb->lock);
+ if (free_adbfind(adb, &find)) {
+ check_exit(adb);
+ }
+ UNLOCK(&adb->lock);
+}
+
+void
+dns_adb_cancelfind(dns_adbfind_t *find) {
+ isc_event_t *ev;
+ isc_task_t *task;
+ dns_adb_t *adb;
+ int bucket;
+ int unlock_bucket;
+
+ LOCK(&find->lock);
+
+ DP(DEF_LEVEL, "dns_adb_cancelfind on find %p", find);
+
+ adb = find->adb;
+ REQUIRE(DNS_ADB_VALID(adb));
+
+ REQUIRE(!FIND_EVENTFREED(find));
+ REQUIRE(FIND_WANTEVENT(find));
+
+ bucket = find->name_bucket;
+ if (bucket == DNS_ADB_INVALIDBUCKET) {
+ goto cleanup;
+ }
+
+ /*
+ * We need to get the adbname's lock to unlink the find.
+ */
+ unlock_bucket = bucket;
+ violate_locking_hierarchy(&find->lock, &adb->namelocks[unlock_bucket]);
+ bucket = find->name_bucket;
+ if (bucket != DNS_ADB_INVALIDBUCKET) {
+ ISC_LIST_UNLINK(find->adbname->finds, find, plink);
+ find->adbname = NULL;
+ find->name_bucket = DNS_ADB_INVALIDBUCKET;
+ }
+ UNLOCK(&adb->namelocks[unlock_bucket]);
+ bucket = DNS_ADB_INVALIDBUCKET;
+ POST(bucket);
+
+cleanup:
+
+ if (!FIND_EVENTSENT(find)) {
+ ev = &find->event;
+ task = ev->ev_sender;
+ ev->ev_sender = find;
+ ev->ev_type = DNS_EVENT_ADBCANCELED;
+ ev->ev_destroy = event_free;
+ ev->ev_destroy_arg = find;
+ find->result_v4 = ISC_R_CANCELED;
+ find->result_v6 = ISC_R_CANCELED;
+
+ DP(DEF_LEVEL, "sending event %p to task %p for find %p", ev,
+ task, find);
+
+ isc_task_sendanddetach(&task, (isc_event_t **)&ev);
+ }
+
+ UNLOCK(&find->lock);
+}
+
+void
+dns_adb_dump(dns_adb_t *adb, FILE *f) {
+ unsigned int i;
+ isc_stdtime_t now;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(f != NULL);
+
+ /*
+ * Lock the adb itself, lock all the name buckets, then lock all
+ * the entry buckets. This should put the adb into a state where
+ * nothing can change, so we can iterate through everything and
+ * print at our leisure.
+ */
+
+ LOCK(&adb->lock);
+ isc_stdtime_get(&now);
+
+ for (i = 0; i < adb->nnames; i++) {
+ RUNTIME_CHECK(!cleanup_names(adb, i, now));
+ }
+ for (i = 0; i < adb->nentries; i++) {
+ RUNTIME_CHECK(!cleanup_entries(adb, i, now));
+ }
+
+ dump_adb(adb, f, false, now);
+ UNLOCK(&adb->lock);
+}
+
+static void
+dump_ttl(FILE *f, const char *legend, isc_stdtime_t value, isc_stdtime_t now) {
+ if (value == INT_MAX) {
+ return;
+ }
+ fprintf(f, " [%s TTL %d]", legend, (int)(value - now));
+}
+
+static void
+dump_adb(dns_adb_t *adb, FILE *f, bool debug, isc_stdtime_t now) {
+ dns_adbname_t *name;
+ dns_adbentry_t *entry;
+
+ fprintf(f, ";\n; Address database dump\n;\n");
+ fprintf(f, "; [edns success/timeout]\n");
+ fprintf(f, "; [plain success/timeout]\n;\n");
+ if (debug) {
+ LOCK(&adb->reflock);
+ fprintf(f,
+ "; addr %p, erefcnt %u, irefcnt %u, finds out "
+ "%" PRIuFAST32 "\n",
+ adb, adb->erefcnt, adb->irefcnt,
+ isc_refcount_current(&adb->nhrefcnt));
+ UNLOCK(&adb->reflock);
+ }
+
+/*
+ * In TSAN mode we need to lock the locks individually, as TSAN
+ * can't handle more than 64 locks locked by one thread.
+ * In regular mode we want a consistent dump so we need to
+ * lock everything.
+ */
+#ifndef __SANITIZE_THREAD__
+ for (size_t i = 0; i < adb->nnames; i++) {
+ LOCK(&adb->namelocks[i]);
+ }
+ for (size_t i = 0; i < adb->nentries; i++) {
+ LOCK(&adb->entrylocks[i]);
+ }
+#endif /* ifndef __SANITIZE_THREAD__ */
+
+ /*
+ * Dump the names
+ */
+ for (size_t i = 0; i < adb->nnames; i++) {
+#ifdef __SANITIZE_THREAD__
+ LOCK(&adb->namelocks[i]);
+#endif /* ifdef __SANITIZE_THREAD__ */
+ name = ISC_LIST_HEAD(adb->names[i]);
+ if (name == NULL) {
+#ifdef __SANITIZE_THREAD__
+ UNLOCK(&adb->namelocks[i]);
+#endif /* ifdef __SANITIZE_THREAD__ */
+ continue;
+ }
+ if (debug) {
+ fprintf(f, "; bucket %zu\n", i);
+ }
+ for (; name != NULL; name = ISC_LIST_NEXT(name, plink)) {
+ if (debug) {
+ fprintf(f, "; name %p (flags %08x)\n", name,
+ name->flags);
+ }
+ fprintf(f, "; ");
+ print_dns_name(f, &name->name);
+ if (dns_name_countlabels(&name->target) > 0) {
+ fprintf(f, " alias ");
+ print_dns_name(f, &name->target);
+ }
+
+ dump_ttl(f, "v4", name->expire_v4, now);
+ dump_ttl(f, "v6", name->expire_v6, now);
+ dump_ttl(f, "target", name->expire_target, now);
+
+ fprintf(f, " [v4 %s] [v6 %s]",
+ errnames[name->fetch_err],
+ errnames[name->fetch6_err]);
+
+ fprintf(f, "\n");
+
+ print_namehook_list(f, "v4", adb, &name->v4, debug,
+ now);
+ print_namehook_list(f, "v6", adb, &name->v6, debug,
+ now);
+
+ if (debug) {
+ print_fetch_list(f, name);
+ print_find_list(f, name);
+ }
+ }
+#ifdef __SANITIZE_THREAD__
+ UNLOCK(&adb->namelocks[i]);
+#endif /* ifdef __SANITIZE_THREAD__ */
+ }
+
+ fprintf(f, ";\n; Unassociated entries\n;\n");
+
+ for (size_t i = 0; i < adb->nentries; i++) {
+#ifdef __SANITIZE_THREAD__
+ LOCK(&adb->entrylocks[i]);
+#endif /* ifdef __SANITIZE_THREAD__ */
+ entry = ISC_LIST_HEAD(adb->entries[i]);
+ while (entry != NULL) {
+ if (entry->nh == 0) {
+ dump_entry(f, adb, entry, debug, now);
+ }
+ entry = ISC_LIST_NEXT(entry, plink);
+ }
+#ifdef __SANITIZE_THREAD__
+ UNLOCK(&adb->entrylocks[i]);
+#endif /* ifdef __SANITIZE_THREAD__ */
+ }
+
+#ifndef __SANITIZE_THREAD__
+ /*
+ * Unlock everything
+ */
+ for (ssize_t i = adb->nentries - 1; i >= 0; i--) {
+ UNLOCK(&adb->entrylocks[i]);
+ }
+ for (ssize_t i = adb->nnames - 1; i >= 0; i--) {
+ UNLOCK(&adb->namelocks[i]);
+ }
+#endif /* ifndef __SANITIZE_THREAD__ */
+}
+
+static void
+dump_entry(FILE *f, dns_adb_t *adb, dns_adbentry_t *entry, bool debug,
+ isc_stdtime_t now) {
+ char addrbuf[ISC_NETADDR_FORMATSIZE];
+ char typebuf[DNS_RDATATYPE_FORMATSIZE];
+ isc_netaddr_t netaddr;
+ dns_adblameinfo_t *li;
+
+ isc_netaddr_fromsockaddr(&netaddr, &entry->sockaddr);
+ isc_netaddr_format(&netaddr, addrbuf, sizeof(addrbuf));
+
+ if (debug) {
+ fprintf(f, ";\t%p: refcnt %u\n", entry, entry->refcnt);
+ }
+
+ fprintf(f,
+ ";\t%s [srtt %u] [flags %08x] [edns %u/%u] "
+ "[plain %u/%u]",
+ addrbuf, entry->srtt, entry->flags, entry->edns, entry->ednsto,
+ entry->plain, entry->plainto);
+ if (entry->udpsize != 0U) {
+ fprintf(f, " [udpsize %u]", entry->udpsize);
+ }
+ if (entry->cookie != NULL) {
+ unsigned int i;
+ fprintf(f, " [cookie=");
+ for (i = 0; i < entry->cookielen; i++) {
+ fprintf(f, "%02x", entry->cookie[i]);
+ }
+ fprintf(f, "]");
+ }
+ if (entry->expires != 0) {
+ fprintf(f, " [ttl %d]", (int)(entry->expires - now));
+ }
+
+ if (adb != NULL && adb->quota != 0 && adb->atr_freq != 0) {
+ uint_fast32_t quota = atomic_load_relaxed(&entry->quota);
+ fprintf(f, " [atr %0.2f] [quota %" PRIuFAST32 "]", entry->atr,
+ quota);
+ }
+
+ fprintf(f, "\n");
+ for (li = ISC_LIST_HEAD(entry->lameinfo); li != NULL;
+ li = ISC_LIST_NEXT(li, plink))
+ {
+ fprintf(f, ";\t\t");
+ print_dns_name(f, &li->qname);
+ dns_rdatatype_format(li->qtype, typebuf, sizeof(typebuf));
+ fprintf(f, " %s [lame TTL %d]\n", typebuf,
+ (int)(li->lame_timer - now));
+ }
+}
+
+void
+dns_adb_dumpfind(dns_adbfind_t *find, FILE *f) {
+ char tmp[512];
+ const char *tmpp;
+ dns_adbaddrinfo_t *ai;
+ isc_sockaddr_t *sa;
+
+ /*
+ * Not used currently, in the API Just In Case we
+ * want to dump out the name and/or entries too.
+ */
+
+ LOCK(&find->lock);
+
+ fprintf(f, ";Find %p\n", find);
+ fprintf(f, ";\tqpending %08x partial %08x options %08x flags %08x\n",
+ find->query_pending, find->partial_result, find->options,
+ find->flags);
+ fprintf(f, ";\tname_bucket %d, name %p, event sender %p\n",
+ find->name_bucket, find->adbname, find->event.ev_sender);
+
+ ai = ISC_LIST_HEAD(find->list);
+ if (ai != NULL) {
+ fprintf(f, "\tAddresses:\n");
+ }
+ while (ai != NULL) {
+ sa = &ai->sockaddr;
+ switch (sa->type.sa.sa_family) {
+ case AF_INET:
+ tmpp = inet_ntop(AF_INET, &sa->type.sin.sin_addr, tmp,
+ sizeof(tmp));
+ break;
+ case AF_INET6:
+ tmpp = inet_ntop(AF_INET6, &sa->type.sin6.sin6_addr,
+ tmp, sizeof(tmp));
+ break;
+ default:
+ tmpp = "UnkFamily";
+ }
+
+ if (tmpp == NULL) {
+ tmpp = "BadAddress";
+ }
+
+ fprintf(f,
+ "\t\tentry %p, flags %08x"
+ " srtt %u addr %s\n",
+ ai->entry, ai->flags, ai->srtt, tmpp);
+
+ ai = ISC_LIST_NEXT(ai, publink);
+ }
+
+ UNLOCK(&find->lock);
+}
+
+static void
+print_dns_name(FILE *f, const dns_name_t *name) {
+ char buf[DNS_NAME_FORMATSIZE];
+
+ INSIST(f != NULL);
+
+ dns_name_format(name, buf, sizeof(buf));
+ fprintf(f, "%s", buf);
+}
+
+static void
+print_namehook_list(FILE *f, const char *legend, dns_adb_t *adb,
+ dns_adbnamehooklist_t *list, bool debug,
+ isc_stdtime_t now) {
+ dns_adbnamehook_t *nh;
+
+ for (nh = ISC_LIST_HEAD(*list); nh != NULL;
+ nh = ISC_LIST_NEXT(nh, plink))
+ {
+ if (debug) {
+ fprintf(f, ";\tHook(%s) %p\n", legend, nh);
+ }
+#ifdef __SANITIZE_THREAD__
+ LOCK(&adb->entrylocks[nh->entry->lock_bucket]);
+#endif
+ dump_entry(f, adb, nh->entry, debug, now);
+#ifdef __SANITIZE_THREAD__
+ UNLOCK(&adb->entrylocks[nh->entry->lock_bucket]);
+#endif
+ }
+}
+
+static void
+print_fetch(FILE *f, dns_adbfetch_t *ft, const char *type) {
+ fprintf(f, "\t\tFetch(%s): %p -> { fetch %p }\n", type, ft, ft->fetch);
+}
+
+static void
+print_fetch_list(FILE *f, dns_adbname_t *n) {
+ if (NAME_FETCH_A(n)) {
+ print_fetch(f, n->fetch_a, "A");
+ }
+ if (NAME_FETCH_AAAA(n)) {
+ print_fetch(f, n->fetch_aaaa, "AAAA");
+ }
+}
+
+static void
+print_find_list(FILE *f, dns_adbname_t *name) {
+ dns_adbfind_t *find;
+
+ find = ISC_LIST_HEAD(name->finds);
+ while (find != NULL) {
+ dns_adb_dumpfind(find, f);
+ find = ISC_LIST_NEXT(find, plink);
+ }
+}
+
+static isc_result_t
+dbfind_name(dns_adbname_t *adbname, isc_stdtime_t now, dns_rdatatype_t rdtype) {
+ isc_result_t result;
+ dns_rdataset_t rdataset;
+ dns_adb_t *adb;
+ dns_fixedname_t foundname;
+ dns_name_t *fname;
+
+ INSIST(DNS_ADBNAME_VALID(adbname));
+ adb = adbname->adb;
+ INSIST(DNS_ADB_VALID(adb));
+ INSIST(rdtype == dns_rdatatype_a || rdtype == dns_rdatatype_aaaa);
+
+ fname = dns_fixedname_initname(&foundname);
+ dns_rdataset_init(&rdataset);
+
+ if (rdtype == dns_rdatatype_a) {
+ adbname->fetch_err = FIND_ERR_UNEXPECTED;
+ } else {
+ adbname->fetch6_err = FIND_ERR_UNEXPECTED;
+ }
+
+ /*
+ * We need to specify whether to search static-stub zones (if
+ * configured) depending on whether this is a "start at zone" lookup,
+ * i.e., whether it's a "bailiwick" glue. If it's bailiwick (in which
+ * case DNS_ADBFIND_STARTATZONE is set) we need to stop the search at
+ * any matching static-stub zone without looking into the cache to honor
+ * the configuration on which server we should send queries to.
+ */
+ result =
+ dns_view_find(adb->view, &adbname->name, rdtype, now,
+ NAME_GLUEOK(adbname) ? DNS_DBFIND_GLUEOK : 0,
+ NAME_HINTOK(adbname),
+ ((adbname->flags & DNS_ADBFIND_STARTATZONE) != 0),
+ NULL, NULL, fname, &rdataset, NULL);
+
+ /* XXXVIX this switch statement is too sparse to gen a jump table. */
+ switch (result) {
+ case DNS_R_GLUE:
+ case DNS_R_HINT:
+ case ISC_R_SUCCESS:
+ /*
+ * Found in the database. Even if we can't copy out
+ * any information, return success, or else a fetch
+ * will be made, which will only make things worse.
+ */
+ if (rdtype == dns_rdatatype_a) {
+ adbname->fetch_err = FIND_ERR_SUCCESS;
+ } else {
+ adbname->fetch6_err = FIND_ERR_SUCCESS;
+ }
+ result = import_rdataset(adbname, &rdataset, now);
+ break;
+ case DNS_R_NXDOMAIN:
+ case DNS_R_NXRRSET:
+ /*
+ * We're authoritative and the data doesn't exist.
+ * Make up a negative cache entry so we don't ask again
+ * for a while.
+ *
+ * XXXRTH What time should we use? I'm putting in 30 seconds
+ * for now.
+ */
+ if (rdtype == dns_rdatatype_a) {
+ adbname->expire_v4 = now + 30;
+ DP(NCACHE_LEVEL,
+ "adb name %p: Caching auth negative entry for A",
+ adbname);
+ if (result == DNS_R_NXDOMAIN) {
+ adbname->fetch_err = FIND_ERR_NXDOMAIN;
+ } else {
+ adbname->fetch_err = FIND_ERR_NXRRSET;
+ }
+ } else {
+ DP(NCACHE_LEVEL,
+ "adb name %p: Caching auth negative entry for AAAA",
+ adbname);
+ adbname->expire_v6 = now + 30;
+ if (result == DNS_R_NXDOMAIN) {
+ adbname->fetch6_err = FIND_ERR_NXDOMAIN;
+ } else {
+ adbname->fetch6_err = FIND_ERR_NXRRSET;
+ }
+ }
+ break;
+ case DNS_R_NCACHENXDOMAIN:
+ case DNS_R_NCACHENXRRSET:
+ /*
+ * We found a negative cache entry. Pull the TTL from it
+ * so we won't ask again for a while.
+ */
+ rdataset.ttl = ttlclamp(rdataset.ttl);
+ if (rdtype == dns_rdatatype_a) {
+ adbname->expire_v4 = rdataset.ttl + now;
+ if (result == DNS_R_NCACHENXDOMAIN) {
+ adbname->fetch_err = FIND_ERR_NXDOMAIN;
+ } else {
+ adbname->fetch_err = FIND_ERR_NXRRSET;
+ }
+ DP(NCACHE_LEVEL,
+ "adb name %p: Caching negative entry for A (ttl %u)",
+ adbname, rdataset.ttl);
+ } else {
+ DP(NCACHE_LEVEL,
+ "adb name %p: Caching negative entry for AAAA (ttl "
+ "%u)",
+ adbname, rdataset.ttl);
+ adbname->expire_v6 = rdataset.ttl + now;
+ if (result == DNS_R_NCACHENXDOMAIN) {
+ adbname->fetch6_err = FIND_ERR_NXDOMAIN;
+ } else {
+ adbname->fetch6_err = FIND_ERR_NXRRSET;
+ }
+ }
+ break;
+ case DNS_R_CNAME:
+ case DNS_R_DNAME:
+ /*
+ * Clear the hint and glue flags, so this will match
+ * more often.
+ */
+ adbname->flags &= ~(DNS_ADBFIND_GLUEOK | DNS_ADBFIND_HINTOK);
+
+ rdataset.ttl = ttlclamp(rdataset.ttl);
+ clean_target(adb, &adbname->target);
+ adbname->expire_target = INT_MAX;
+ result = set_target(adb, &adbname->name, fname, &rdataset,
+ &adbname->target);
+ if (result == ISC_R_SUCCESS) {
+ result = DNS_R_ALIAS;
+ DP(NCACHE_LEVEL, "adb name %p: caching alias target",
+ adbname);
+ adbname->expire_target = rdataset.ttl + now;
+ }
+ if (rdtype == dns_rdatatype_a) {
+ adbname->fetch_err = FIND_ERR_SUCCESS;
+ } else {
+ adbname->fetch6_err = FIND_ERR_SUCCESS;
+ }
+ break;
+ default:
+ break;
+ }
+
+ if (dns_rdataset_isassociated(&rdataset)) {
+ dns_rdataset_disassociate(&rdataset);
+ }
+
+ return (result);
+}
+
+static void
+fetch_callback(isc_task_t *task, isc_event_t *ev) {
+ dns_fetchevent_t *dev;
+ dns_adbname_t *name;
+ dns_adb_t *adb;
+ dns_adbfetch_t *fetch;
+ int bucket;
+ isc_eventtype_t ev_status;
+ isc_stdtime_t now;
+ isc_result_t result;
+ unsigned int address_type;
+ bool want_check_exit = false;
+
+ UNUSED(task);
+
+ INSIST(ev->ev_type == DNS_EVENT_FETCHDONE);
+ dev = (dns_fetchevent_t *)ev;
+ name = ev->ev_arg;
+ INSIST(DNS_ADBNAME_VALID(name));
+ adb = name->adb;
+ INSIST(DNS_ADB_VALID(adb));
+
+ bucket = name->lock_bucket;
+ LOCK(&adb->namelocks[bucket]);
+
+ INSIST(NAME_FETCH_A(name) || NAME_FETCH_AAAA(name));
+ address_type = 0;
+ if (NAME_FETCH_A(name) && (name->fetch_a->fetch == dev->fetch)) {
+ address_type = DNS_ADBFIND_INET;
+ fetch = name->fetch_a;
+ name->fetch_a = NULL;
+ } else if (NAME_FETCH_AAAA(name) &&
+ (name->fetch_aaaa->fetch == dev->fetch))
+ {
+ address_type = DNS_ADBFIND_INET6;
+ fetch = name->fetch_aaaa;
+ name->fetch_aaaa = NULL;
+ } else {
+ fetch = NULL;
+ }
+
+ INSIST(address_type != 0 && fetch != NULL);
+
+ dns_resolver_destroyfetch(&fetch->fetch);
+ dev->fetch = NULL;
+
+ ev_status = DNS_EVENT_ADBNOMOREADDRESSES;
+
+ /*
+ * Cleanup things we don't care about.
+ */
+ if (dev->node != NULL) {
+ dns_db_detachnode(dev->db, &dev->node);
+ }
+ if (dev->db != NULL) {
+ dns_db_detach(&dev->db);
+ }
+
+ /*
+ * If this name is marked as dead, clean up, throwing away
+ * potentially good data.
+ */
+ if (NAME_DEAD(name)) {
+ free_adbfetch(adb, &fetch);
+ isc_event_free(&ev);
+
+ want_check_exit = kill_name(&name, DNS_EVENT_ADBCANCELED);
+
+ UNLOCK(&adb->namelocks[bucket]);
+
+ if (want_check_exit) {
+ LOCK(&adb->lock);
+ check_exit(adb);
+ UNLOCK(&adb->lock);
+ }
+
+ return;
+ }
+
+ isc_stdtime_get(&now);
+
+ /*
+ * If we got a negative cache response, remember it.
+ */
+ if (NCACHE_RESULT(dev->result)) {
+ dev->rdataset->ttl = ttlclamp(dev->rdataset->ttl);
+ if (address_type == DNS_ADBFIND_INET) {
+ DP(NCACHE_LEVEL,
+ "adb fetch name %p: "
+ "caching negative entry for A (ttl %u)",
+ name, dev->rdataset->ttl);
+ name->expire_v4 = ISC_MIN(name->expire_v4,
+ dev->rdataset->ttl + now);
+ if (dev->result == DNS_R_NCACHENXDOMAIN) {
+ name->fetch_err = FIND_ERR_NXDOMAIN;
+ } else {
+ name->fetch_err = FIND_ERR_NXRRSET;
+ }
+ inc_stats(adb, dns_resstatscounter_gluefetchv4fail);
+ } else {
+ DP(NCACHE_LEVEL,
+ "adb fetch name %p: "
+ "caching negative entry for AAAA (ttl %u)",
+ name, dev->rdataset->ttl);
+ name->expire_v6 = ISC_MIN(name->expire_v6,
+ dev->rdataset->ttl + now);
+ if (dev->result == DNS_R_NCACHENXDOMAIN) {
+ name->fetch6_err = FIND_ERR_NXDOMAIN;
+ } else {
+ name->fetch6_err = FIND_ERR_NXRRSET;
+ }
+ inc_stats(adb, dns_resstatscounter_gluefetchv6fail);
+ }
+ goto out;
+ }
+
+ /*
+ * Handle CNAME/DNAME.
+ */
+ if (dev->result == DNS_R_CNAME || dev->result == DNS_R_DNAME) {
+ dev->rdataset->ttl = ttlclamp(dev->rdataset->ttl);
+ clean_target(adb, &name->target);
+ name->expire_target = INT_MAX;
+ result = set_target(adb, &name->name, dev->foundname,
+ dev->rdataset, &name->target);
+ if (result == ISC_R_SUCCESS) {
+ DP(NCACHE_LEVEL,
+ "adb fetch name %p: caching alias target", name);
+ name->expire_target = dev->rdataset->ttl + now;
+ }
+ goto check_result;
+ }
+
+ /*
+ * Did we get back junk? If so, and there are no more fetches
+ * sitting out there, tell all the finds about it.
+ */
+ if (dev->result != ISC_R_SUCCESS) {
+ char buf[DNS_NAME_FORMATSIZE];
+
+ dns_name_format(&name->name, buf, sizeof(buf));
+ DP(DEF_LEVEL, "adb: fetch of '%s' %s failed: %s", buf,
+ address_type == DNS_ADBFIND_INET ? "A" : "AAAA",
+ isc_result_totext(dev->result));
+ /*
+ * Don't record a failure unless this is the initial
+ * fetch of a chain.
+ */
+ if (fetch->depth > 1) {
+ goto out;
+ }
+ /* XXXMLG Don't pound on bad servers. */
+ if (address_type == DNS_ADBFIND_INET) {
+ name->expire_v4 = ISC_MIN(name->expire_v4, now + 10);
+ name->fetch_err = FIND_ERR_FAILURE;
+ inc_stats(adb, dns_resstatscounter_gluefetchv4fail);
+ } else {
+ name->expire_v6 = ISC_MIN(name->expire_v6, now + 10);
+ name->fetch6_err = FIND_ERR_FAILURE;
+ inc_stats(adb, dns_resstatscounter_gluefetchv6fail);
+ }
+ goto out;
+ }
+
+ /*
+ * We got something potentially useful.
+ */
+ result = import_rdataset(name, &fetch->rdataset, now);
+
+check_result:
+ if (result == ISC_R_SUCCESS) {
+ ev_status = DNS_EVENT_ADBMOREADDRESSES;
+ if (address_type == DNS_ADBFIND_INET) {
+ name->fetch_err = FIND_ERR_SUCCESS;
+ } else {
+ name->fetch6_err = FIND_ERR_SUCCESS;
+ }
+ }
+
+out:
+ free_adbfetch(adb, &fetch);
+ isc_event_free(&ev);
+
+ clean_finds_at_name(name, ev_status, address_type);
+
+ UNLOCK(&adb->namelocks[bucket]);
+}
+
+static isc_result_t
+fetch_name(dns_adbname_t *adbname, bool start_at_zone, unsigned int depth,
+ isc_counter_t *qc, dns_rdatatype_t type) {
+ isc_result_t result;
+ dns_adbfetch_t *fetch = NULL;
+ dns_adb_t *adb;
+ dns_fixedname_t fixed;
+ dns_name_t *name;
+ dns_rdataset_t rdataset;
+ dns_rdataset_t *nameservers;
+ unsigned int options;
+
+ INSIST(DNS_ADBNAME_VALID(adbname));
+ adb = adbname->adb;
+ INSIST(DNS_ADB_VALID(adb));
+
+ INSIST((type == dns_rdatatype_a && !NAME_FETCH_A(adbname)) ||
+ (type == dns_rdatatype_aaaa && !NAME_FETCH_AAAA(adbname)));
+
+ adbname->fetch_err = FIND_ERR_NOTFOUND;
+
+ name = NULL;
+ nameservers = NULL;
+ dns_rdataset_init(&rdataset);
+
+ options = DNS_FETCHOPT_NOVALIDATE;
+ if (start_at_zone) {
+ DP(ENTER_LEVEL, "fetch_name: starting at zone for name %p",
+ adbname);
+ name = dns_fixedname_initname(&fixed);
+ result = dns_view_findzonecut(adb->view, &adbname->name, name,
+ NULL, 0, 0, true, false,
+ &rdataset, NULL);
+ if (result != ISC_R_SUCCESS && result != DNS_R_HINT) {
+ goto cleanup;
+ }
+ nameservers = &rdataset;
+ options |= DNS_FETCHOPT_UNSHARED;
+ }
+
+ fetch = new_adbfetch(adb);
+ fetch->depth = depth;
+
+ /*
+ * We're not minimizing this query, as nothing user-related should
+ * be leaked here.
+ * However, if we'd ever want to change it we'd have to modify
+ * createfetch to find deepest cached name when we're providing
+ * domain and nameservers.
+ */
+ result = dns_resolver_createfetch(
+ adb->view->resolver, &adbname->name, type, name, nameservers,
+ NULL, NULL, 0, options, depth, qc, adb->task, fetch_callback,
+ adbname, &fetch->rdataset, NULL, &fetch->fetch);
+ if (result != ISC_R_SUCCESS) {
+ DP(ENTER_LEVEL, "fetch_name: createfetch failed with %s",
+ isc_result_totext(result));
+ goto cleanup;
+ }
+
+ if (type == dns_rdatatype_a) {
+ adbname->fetch_a = fetch;
+ inc_stats(adb, dns_resstatscounter_gluefetchv4);
+ } else {
+ adbname->fetch_aaaa = fetch;
+ inc_stats(adb, dns_resstatscounter_gluefetchv6);
+ }
+ fetch = NULL; /* Keep us from cleaning this up below. */
+
+cleanup:
+ if (fetch != NULL) {
+ free_adbfetch(adb, &fetch);
+ }
+ if (dns_rdataset_isassociated(&rdataset)) {
+ dns_rdataset_disassociate(&rdataset);
+ }
+
+ return (result);
+}
+
+/*
+ * XXXMLG Needs to take a find argument and an address info, no zone or adb,
+ * since these can be extracted from the find itself.
+ */
+isc_result_t
+dns_adb_marklame(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
+ const dns_name_t *qname, dns_rdatatype_t qtype,
+ isc_stdtime_t expire_time) {
+ dns_adblameinfo_t *li;
+ int bucket;
+ isc_result_t result = ISC_R_SUCCESS;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+ REQUIRE(qname != NULL);
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+ li = ISC_LIST_HEAD(addr->entry->lameinfo);
+ while (li != NULL &&
+ (li->qtype != qtype || !dns_name_equal(qname, &li->qname)))
+ {
+ li = ISC_LIST_NEXT(li, plink);
+ }
+ if (li != NULL) {
+ if (expire_time > li->lame_timer) {
+ li->lame_timer = expire_time;
+ }
+ goto unlock;
+ }
+ li = new_adblameinfo(adb, qname, qtype);
+ li->lame_timer = expire_time;
+
+ ISC_LIST_PREPEND(addr->entry->lameinfo, li, plink);
+unlock:
+ UNLOCK(&adb->entrylocks[bucket]);
+
+ return (result);
+}
+
+void
+dns_adb_adjustsrtt(dns_adb_t *adb, dns_adbaddrinfo_t *addr, unsigned int rtt,
+ unsigned int factor) {
+ int bucket;
+ isc_stdtime_t now = 0;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+ REQUIRE(factor <= 10);
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ if (addr->entry->expires == 0 || factor == DNS_ADB_RTTADJAGE) {
+ isc_stdtime_get(&now);
+ }
+ adjustsrtt(addr, rtt, factor, now);
+
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+void
+dns_adb_agesrtt(dns_adb_t *adb, dns_adbaddrinfo_t *addr, isc_stdtime_t now) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ adjustsrtt(addr, 0, DNS_ADB_RTTADJAGE, now);
+
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+static void
+adjustsrtt(dns_adbaddrinfo_t *addr, unsigned int rtt, unsigned int factor,
+ isc_stdtime_t now) {
+ uint64_t new_srtt;
+
+ if (factor == DNS_ADB_RTTADJAGE) {
+ if (addr->entry->lastage != now) {
+ new_srtt = addr->entry->srtt;
+ new_srtt <<= 9;
+ new_srtt -= addr->entry->srtt;
+ new_srtt >>= 9;
+ addr->entry->lastage = now;
+ } else {
+ new_srtt = addr->entry->srtt;
+ }
+ } else {
+ new_srtt = ((uint64_t)addr->entry->srtt / 10 * factor) +
+ ((uint64_t)rtt / 10 * (10 - factor));
+ }
+
+ addr->entry->srtt = (unsigned int)new_srtt;
+ addr->srtt = (unsigned int)new_srtt;
+
+ if (addr->entry->expires == 0) {
+ addr->entry->expires = now + ADB_ENTRY_WINDOW;
+ }
+}
+
+void
+dns_adb_changeflags(dns_adb_t *adb, dns_adbaddrinfo_t *addr, unsigned int bits,
+ unsigned int mask) {
+ int bucket;
+ isc_stdtime_t now;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ REQUIRE((bits & ENTRY_IS_DEAD) == 0);
+ REQUIRE((mask & ENTRY_IS_DEAD) == 0);
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ addr->entry->flags = (addr->entry->flags & ~mask) | (bits & mask);
+ if (addr->entry->expires == 0) {
+ isc_stdtime_get(&now);
+ addr->entry->expires = now + ADB_ENTRY_WINDOW;
+ }
+
+ /*
+ * Note that we do not update the other bits in addr->flags with
+ * the most recent values from addr->entry->flags.
+ */
+ addr->flags = (addr->flags & ~mask) | (bits & mask);
+
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+/*
+ * The polynomial backoff curve (10000 / ((10 + n) / 10)^(3/2)) <0..99> drops
+ * fairly aggressively at first, then slows down and tails off at around 2-3%.
+ *
+ * These will be used to make quota adjustments.
+ */
+static int quota_adj[] = {
+ 10000, 8668, 7607, 6747, 6037, 5443, 4941, 4512, 4141, 3818, 3536,
+ 3286, 3065, 2867, 2690, 2530, 2385, 2254, 2134, 2025, 1925, 1832,
+ 1747, 1668, 1595, 1527, 1464, 1405, 1350, 1298, 1250, 1205, 1162,
+ 1121, 1083, 1048, 1014, 981, 922, 894, 868, 843, 820, 797,
+ 775, 755, 735, 716, 698, 680, 664, 648, 632, 618, 603,
+ 590, 577, 564, 552, 540, 529, 518, 507, 497, 487, 477,
+ 468, 459, 450, 442, 434, 426, 418, 411, 404, 397, 390,
+ 383, 377, 370, 364, 358, 353, 347, 342, 336, 331, 326,
+ 321, 316, 312, 307, 303, 298, 294, 290, 286, 282, 278
+};
+
+#define QUOTA_ADJ_SIZE (sizeof(quota_adj) / sizeof(quota_adj[0]))
+
+/*
+ * Caller must hold adbentry lock
+ */
+static void
+maybe_adjust_quota(dns_adb_t *adb, dns_adbaddrinfo_t *addr, bool timeout) {
+ double tr;
+
+ UNUSED(adb);
+
+ if (adb->quota == 0 || adb->atr_freq == 0) {
+ return;
+ }
+
+ if (timeout) {
+ addr->entry->timeouts++;
+ }
+
+ if (addr->entry->completed++ <= adb->atr_freq) {
+ return;
+ }
+
+ /*
+ * Calculate an exponential rolling average of the timeout ratio
+ *
+ * XXX: Integer arithmetic might be better than floating point
+ */
+ tr = (double)addr->entry->timeouts / addr->entry->completed;
+ addr->entry->timeouts = addr->entry->completed = 0;
+ INSIST(addr->entry->atr >= 0.0);
+ INSIST(addr->entry->atr <= 1.0);
+ INSIST(adb->atr_discount >= 0.0);
+ INSIST(adb->atr_discount <= 1.0);
+ addr->entry->atr *= 1.0 - adb->atr_discount;
+ addr->entry->atr += tr * adb->atr_discount;
+ addr->entry->atr = ISC_CLAMP(addr->entry->atr, 0.0, 1.0);
+
+ if (addr->entry->atr < adb->atr_low && addr->entry->mode > 0) {
+ uint_fast32_t new_quota =
+ adb->quota * quota_adj[--addr->entry->mode] / 10000;
+ atomic_store_release(&addr->entry->quota,
+ ISC_MAX(1, new_quota));
+ log_quota(addr->entry,
+ "atr %0.2f, quota increased to %" PRIuFAST32,
+ addr->entry->atr, new_quota);
+ } else if (addr->entry->atr > adb->atr_high &&
+ addr->entry->mode < (QUOTA_ADJ_SIZE - 1))
+ {
+ uint_fast32_t new_quota =
+ adb->quota * quota_adj[++addr->entry->mode] / 10000;
+ atomic_store_release(&addr->entry->quota,
+ ISC_MAX(1, new_quota));
+ log_quota(addr->entry,
+ "atr %0.2f, quota decreased to %" PRIuFAST32,
+ addr->entry->atr, new_quota);
+ }
+}
+
+#define EDNSTOS 3U
+
+void
+dns_adb_plainresponse(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ maybe_adjust_quota(adb, addr, false);
+
+ addr->entry->plain++;
+ if (addr->entry->plain == 0xff) {
+ addr->entry->edns >>= 1;
+ addr->entry->ednsto >>= 1;
+ addr->entry->plain >>= 1;
+ addr->entry->plainto >>= 1;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+void
+dns_adb_timeout(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ maybe_adjust_quota(adb, addr, true);
+
+ addr->entry->plainto++;
+ if (addr->entry->plainto == 0xff) {
+ addr->entry->edns >>= 1;
+ addr->entry->ednsto >>= 1;
+ addr->entry->plain >>= 1;
+ addr->entry->plainto >>= 1;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+void
+dns_adb_ednsto(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ maybe_adjust_quota(adb, addr, true);
+
+ addr->entry->ednsto++;
+ if (addr->entry->ednsto == 0xff) {
+ addr->entry->edns >>= 1;
+ addr->entry->ednsto >>= 1;
+ addr->entry->plain >>= 1;
+ addr->entry->plainto >>= 1;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+void
+dns_adb_setudpsize(dns_adb_t *adb, dns_adbaddrinfo_t *addr, unsigned int size) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+ if (size < 512U) {
+ size = 512U;
+ }
+ if (size > addr->entry->udpsize) {
+ addr->entry->udpsize = size;
+ }
+
+ maybe_adjust_quota(adb, addr, false);
+
+ addr->entry->edns++;
+ if (addr->entry->edns == 0xff) {
+ addr->entry->edns >>= 1;
+ addr->entry->ednsto >>= 1;
+ addr->entry->plain >>= 1;
+ addr->entry->plainto >>= 1;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+unsigned int
+dns_adb_getudpsize(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ int bucket;
+ unsigned int size;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+ size = addr->entry->udpsize;
+ UNLOCK(&adb->entrylocks[bucket]);
+
+ return (size);
+}
+
+void
+dns_adb_setcookie(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
+ const unsigned char *cookie, size_t len) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ if (addr->entry->cookie != NULL &&
+ (cookie == NULL || len != addr->entry->cookielen))
+ {
+ isc_mem_put(adb->mctx, addr->entry->cookie,
+ addr->entry->cookielen);
+ addr->entry->cookie = NULL;
+ addr->entry->cookielen = 0;
+ }
+
+ if (addr->entry->cookie == NULL && cookie != NULL && len != 0U) {
+ addr->entry->cookie = isc_mem_get(adb->mctx, len);
+ addr->entry->cookielen = (uint16_t)len;
+ }
+
+ if (addr->entry->cookie != NULL) {
+ memmove(addr->entry->cookie, cookie, len);
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+}
+
+size_t
+dns_adb_getcookie(dns_adb_t *adb, dns_adbaddrinfo_t *addr,
+ unsigned char *cookie, size_t len) {
+ int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+ if (cookie != NULL && addr->entry->cookie != NULL &&
+ len >= addr->entry->cookielen)
+ {
+ memmove(cookie, addr->entry->cookie, addr->entry->cookielen);
+ len = addr->entry->cookielen;
+ } else {
+ len = 0;
+ }
+ UNLOCK(&adb->entrylocks[bucket]);
+
+ return (len);
+}
+
+isc_result_t
+dns_adb_findaddrinfo(dns_adb_t *adb, const isc_sockaddr_t *sa,
+ dns_adbaddrinfo_t **addrp, isc_stdtime_t now) {
+ int bucket;
+ dns_adbentry_t *entry;
+ dns_adbaddrinfo_t *addr;
+ isc_result_t result;
+ in_port_t port;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(addrp != NULL && *addrp == NULL);
+
+ UNUSED(now);
+
+ result = ISC_R_SUCCESS;
+ bucket = DNS_ADB_INVALIDBUCKET;
+ entry = find_entry_and_lock(adb, sa, &bucket, now);
+ INSIST(bucket != DNS_ADB_INVALIDBUCKET);
+ if (adb->entry_sd[bucket]) {
+ result = ISC_R_SHUTTINGDOWN;
+ goto unlock;
+ }
+ if (entry == NULL) {
+ /*
+ * We don't know anything about this address.
+ */
+ entry = new_adbentry(adb);
+ entry->sockaddr = *sa;
+ link_entry(adb, bucket, entry);
+ DP(ENTER_LEVEL, "findaddrinfo: new entry %p", entry);
+ } else {
+ DP(ENTER_LEVEL, "findaddrinfo: found entry %p", entry);
+ }
+
+ port = isc_sockaddr_getport(sa);
+ addr = new_adbaddrinfo(adb, entry, port);
+ inc_entry_refcnt(adb, entry, false);
+ *addrp = addr;
+
+unlock:
+ UNLOCK(&adb->entrylocks[bucket]);
+
+ return (result);
+}
+
+void
+dns_adb_freeaddrinfo(dns_adb_t *adb, dns_adbaddrinfo_t **addrp) {
+ dns_adbaddrinfo_t *addr;
+ dns_adbentry_t *entry;
+ int bucket;
+ isc_stdtime_t now;
+ bool want_check_exit = false;
+ bool overmem;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(addrp != NULL);
+ addr = *addrp;
+ *addrp = NULL;
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+ entry = addr->entry;
+ REQUIRE(DNS_ADBENTRY_VALID(entry));
+
+ overmem = isc_mem_isovermem(adb->mctx);
+
+ bucket = addr->entry->lock_bucket;
+ LOCK(&adb->entrylocks[bucket]);
+
+ isc_stdtime_get(&now);
+ if (entry->expires == 0) {
+ entry->expires = now + ADB_ENTRY_WINDOW;
+ }
+
+ want_check_exit = dec_entry_refcnt(adb, overmem, entry, false, now);
+
+ UNLOCK(&adb->entrylocks[bucket]);
+
+ addr->entry = NULL;
+ free_adbaddrinfo(adb, &addr);
+
+ if (want_check_exit) {
+ LOCK(&adb->lock);
+ check_exit(adb);
+ UNLOCK(&adb->lock);
+ }
+}
+
+void
+dns_adb_flush(dns_adb_t *adb) {
+ unsigned int i;
+
+ INSIST(DNS_ADB_VALID(adb));
+
+ LOCK(&adb->lock);
+
+ /*
+ * Call our cleanup routines.
+ */
+ for (i = 0; i < adb->nnames; i++) {
+ RUNTIME_CHECK(!cleanup_names(adb, i, INT_MAX));
+ }
+ for (i = 0; i < adb->nentries; i++) {
+ RUNTIME_CHECK(!cleanup_entries(adb, i, INT_MAX));
+ }
+
+#ifdef DUMP_ADB_AFTER_CLEANING
+ dump_adb(adb, stdout, true, INT_MAX);
+#endif /* ifdef DUMP_ADB_AFTER_CLEANING */
+
+ UNLOCK(&adb->lock);
+}
+
+void
+dns_adb_flushname(dns_adb_t *adb, const dns_name_t *name) {
+ dns_adbname_t *adbname;
+ dns_adbname_t *nextname;
+ unsigned int bucket;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(name != NULL);
+
+ LOCK(&adb->lock);
+ bucket = dns_name_hash(name, false) % adb->nnames;
+ LOCK(&adb->namelocks[bucket]);
+ adbname = ISC_LIST_HEAD(adb->names[bucket]);
+ while (adbname != NULL) {
+ nextname = ISC_LIST_NEXT(adbname, plink);
+ if (!NAME_DEAD(adbname) && dns_name_equal(name, &adbname->name))
+ {
+ RUNTIME_CHECK(
+ !kill_name(&adbname, DNS_EVENT_ADBCANCELED));
+ }
+ adbname = nextname;
+ }
+ UNLOCK(&adb->namelocks[bucket]);
+ UNLOCK(&adb->lock);
+}
+
+void
+dns_adb_flushnames(dns_adb_t *adb, const dns_name_t *name) {
+ dns_adbname_t *adbname, *nextname;
+ unsigned int i;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(name != NULL);
+
+ LOCK(&adb->lock);
+ for (i = 0; i < adb->nnames; i++) {
+ LOCK(&adb->namelocks[i]);
+ adbname = ISC_LIST_HEAD(adb->names[i]);
+ while (adbname != NULL) {
+ bool ret;
+ nextname = ISC_LIST_NEXT(adbname, plink);
+ if (!NAME_DEAD(adbname) &&
+ dns_name_issubdomain(&adbname->name, name))
+ {
+ ret = kill_name(&adbname,
+ DNS_EVENT_ADBCANCELED);
+ RUNTIME_CHECK(!ret);
+ }
+ adbname = nextname;
+ }
+ UNLOCK(&adb->namelocks[i]);
+ }
+ UNLOCK(&adb->lock);
+}
+
+static void
+water(void *arg, int mark) {
+ /*
+ * We're going to change the way to handle overmem condition: use
+ * isc_mem_isovermem() instead of storing the state via this callback,
+ * since the latter way tends to cause race conditions.
+ * To minimize the change, and in case we re-enable the callback
+ * approach, however, keep this function at the moment.
+ */
+
+ dns_adb_t *adb = arg;
+ bool overmem = (mark == ISC_MEM_HIWATER);
+
+ REQUIRE(DNS_ADB_VALID(adb));
+
+ DP(ISC_LOG_DEBUG(1), "adb reached %s water mark",
+ overmem ? "high" : "low");
+}
+
+void
+dns_adb_setadbsize(dns_adb_t *adb, size_t size) {
+ size_t hiwater, lowater;
+
+ INSIST(DNS_ADB_VALID(adb));
+
+ if (size != 0U && size < DNS_ADB_MINADBSIZE) {
+ size = DNS_ADB_MINADBSIZE;
+ }
+
+ hiwater = size - (size >> 3); /* Approximately 7/8ths. */
+ lowater = size - (size >> 2); /* Approximately 3/4ths. */
+
+ if (size == 0U || hiwater == 0U || lowater == 0U) {
+ isc_mem_clearwater(adb->mctx);
+ } else {
+ isc_mem_setwater(adb->mctx, water, adb, hiwater, lowater);
+ }
+}
+
+void
+dns_adb_setquota(dns_adb_t *adb, uint32_t quota, uint32_t freq, double low,
+ double high, double discount) {
+ REQUIRE(DNS_ADB_VALID(adb));
+
+ adb->quota = quota;
+ adb->atr_freq = freq;
+ adb->atr_low = low;
+ adb->atr_high = high;
+ adb->atr_discount = discount;
+}
+
+bool
+dns_adbentry_overquota(dns_adbentry_t *entry) {
+ REQUIRE(DNS_ADBENTRY_VALID(entry));
+
+ uint_fast32_t quota = atomic_load_relaxed(&entry->quota);
+ uint_fast32_t active = atomic_load_acquire(&entry->active);
+
+ return (quota != 0 && active >= quota);
+}
+
+void
+dns_adb_beginudpfetch(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ uint_fast32_t active;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ active = atomic_fetch_add_relaxed(&addr->entry->active, 1);
+ INSIST(active != UINT32_MAX);
+}
+
+void
+dns_adb_endudpfetch(dns_adb_t *adb, dns_adbaddrinfo_t *addr) {
+ uint_fast32_t active;
+
+ REQUIRE(DNS_ADB_VALID(adb));
+ REQUIRE(DNS_ADBADDRINFO_VALID(addr));
+
+ active = atomic_fetch_sub_release(&addr->entry->active, 1);
+ INSIST(active != 0);
+}