diff options
Diffstat (limited to 'contrib/bind9/lib/dns/dispatch.c')
| -rw-r--r-- | contrib/bind9/lib/dns/dispatch.c | 2674 |
1 files changed, 0 insertions, 2674 deletions
diff --git a/contrib/bind9/lib/dns/dispatch.c b/contrib/bind9/lib/dns/dispatch.c deleted file mode 100644 index f3ef091..0000000 --- a/contrib/bind9/lib/dns/dispatch.c +++ /dev/null @@ -1,2674 +0,0 @@ -/* - * Copyright (C) 2004-2007 Internet Systems Consortium, Inc. ("ISC") - * Copyright (C) 1999-2003 Internet Software Consortium. - * - * Permission to use, copy, modify, and/or distribute this software for any - * purpose with or without fee is hereby granted, provided that the above - * copyright notice and this permission notice appear in all copies. - * - * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH - * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY - * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, - * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM - * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE - * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR - * PERFORMANCE OF THIS SOFTWARE. - */ - -/* $Id: dispatch.c,v 1.116.18.19 2007/08/28 07:20:04 tbox Exp $ */ - -/*! \file */ - -#include <config.h> - -#include <stdlib.h> -#include <sys/types.h> -#include <unistd.h> - -#include <isc/entropy.h> -#include <isc/mem.h> -#include <isc/mutex.h> -#include <isc/print.h> -#include <isc/string.h> -#include <isc/task.h> -#include <isc/time.h> -#include <isc/util.h> - -#include <dns/acl.h> -#include <dns/dispatch.h> -#include <dns/events.h> -#include <dns/log.h> -#include <dns/message.h> -#include <dns/portlist.h> -#include <dns/tcpmsg.h> -#include <dns/types.h> - -typedef ISC_LIST(dns_dispentry_t) dns_displist_t; - -typedef struct dns_nsid { - isc_uint16_t nsid_state; - isc_uint16_t *nsid_vtable; - isc_uint16_t *nsid_pool; - isc_uint16_t nsid_a1, nsid_a2, nsid_a3; - isc_uint16_t nsid_c1, nsid_c2, nsid_c3; - isc_uint16_t nsid_state2; - isc_boolean_t nsid_usepool; -} dns_nsid_t; - -typedef struct dns_qid { - unsigned int magic; - unsigned int qid_nbuckets; /*%< hash table size */ - unsigned int qid_increment; /*%< id increment on collision */ - isc_mutex_t lock; - dns_nsid_t nsid; - dns_displist_t *qid_table; /*%< the table itself */ -} dns_qid_t; - -struct dns_dispatchmgr { - /* Unlocked. */ - unsigned int magic; - isc_mem_t *mctx; - dns_acl_t *blackhole; - dns_portlist_t *portlist; - - /* Locked by "lock". */ - isc_mutex_t lock; - unsigned int state; - ISC_LIST(dns_dispatch_t) list; - - /* locked by buffer lock */ - dns_qid_t *qid; - isc_mutex_t buffer_lock; - unsigned int buffers; /*%< allocated buffers */ - unsigned int buffersize; /*%< size of each buffer */ - unsigned int maxbuffers; /*%< max buffers */ - - /* Locked internally. */ - isc_mutex_t pool_lock; - isc_mempool_t *epool; /*%< memory pool for events */ - isc_mempool_t *rpool; /*%< memory pool for replies */ - isc_mempool_t *dpool; /*%< dispatch allocations */ - isc_mempool_t *bpool; /*%< memory pool for buffers */ - - isc_entropy_t *entropy; /*%< entropy source */ -}; - -#define MGR_SHUTTINGDOWN 0x00000001U -#define MGR_IS_SHUTTINGDOWN(l) (((l)->state & MGR_SHUTTINGDOWN) != 0) - -#define IS_PRIVATE(d) (((d)->attributes & DNS_DISPATCHATTR_PRIVATE) != 0) - -struct dns_dispentry { - unsigned int magic; - dns_dispatch_t *disp; - dns_messageid_t id; - unsigned int bucket; - isc_sockaddr_t host; - isc_task_t *task; - isc_taskaction_t action; - void *arg; - isc_boolean_t item_out; - ISC_LIST(dns_dispatchevent_t) items; - ISC_LINK(dns_dispentry_t) link; -}; - -#define INVALID_BUCKET (0xffffdead) - -struct dns_dispatch { - /* Unlocked. */ - unsigned int magic; /*%< magic */ - dns_dispatchmgr_t *mgr; /*%< dispatch manager */ - isc_task_t *task; /*%< internal task */ - isc_socket_t *socket; /*%< isc socket attached to */ - isc_sockaddr_t local; /*%< local address */ - unsigned int maxrequests; /*%< max requests */ - isc_event_t *ctlevent; - - /*% Locked by mgr->lock. */ - ISC_LINK(dns_dispatch_t) link; - - /* Locked by "lock". */ - isc_mutex_t lock; /*%< locks all below */ - isc_sockettype_t socktype; - unsigned int attributes; - unsigned int refcount; /*%< number of users */ - dns_dispatchevent_t *failsafe_ev; /*%< failsafe cancel event */ - unsigned int shutting_down : 1, - shutdown_out : 1, - connected : 1, - tcpmsg_valid : 1, - recv_pending : 1; /*%< is a recv() pending? */ - isc_result_t shutdown_why; - unsigned int requests; /*%< how many requests we have */ - unsigned int tcpbuffers; /*%< allocated buffers */ - dns_tcpmsg_t tcpmsg; /*%< for tcp streams */ - dns_qid_t *qid; -}; - -#define QID_MAGIC ISC_MAGIC('Q', 'i', 'd', ' ') -#define VALID_QID(e) ISC_MAGIC_VALID((e), QID_MAGIC) - -#define RESPONSE_MAGIC ISC_MAGIC('D', 'r', 's', 'p') -#define VALID_RESPONSE(e) ISC_MAGIC_VALID((e), RESPONSE_MAGIC) - -#define DISPATCH_MAGIC ISC_MAGIC('D', 'i', 's', 'p') -#define VALID_DISPATCH(e) ISC_MAGIC_VALID((e), DISPATCH_MAGIC) - -#define DNS_DISPATCHMGR_MAGIC ISC_MAGIC('D', 'M', 'g', 'r') -#define VALID_DISPATCHMGR(e) ISC_MAGIC_VALID((e), DNS_DISPATCHMGR_MAGIC) - -#define DNS_QID(disp) ((disp)->socktype == isc_sockettype_tcp) ? \ - (disp)->qid : (disp)->mgr->qid -/* - * Statics. - */ -static dns_dispentry_t *bucket_search(dns_qid_t *, isc_sockaddr_t *, - dns_messageid_t, unsigned int); -static isc_boolean_t destroy_disp_ok(dns_dispatch_t *); -static void destroy_disp(isc_task_t *task, isc_event_t *event); -static void udp_recv(isc_task_t *, isc_event_t *); -static void tcp_recv(isc_task_t *, isc_event_t *); -static void startrecv(dns_dispatch_t *); -static dns_messageid_t dns_randomid(dns_nsid_t *); -static isc_uint32_t dns_hash(dns_qid_t *, isc_sockaddr_t *, dns_messageid_t); -static void free_buffer(dns_dispatch_t *disp, void *buf, unsigned int len); -static void *allocate_udp_buffer(dns_dispatch_t *disp); -static inline void free_event(dns_dispatch_t *disp, dns_dispatchevent_t *ev); -static inline dns_dispatchevent_t *allocate_event(dns_dispatch_t *disp); -static void do_cancel(dns_dispatch_t *disp); -static dns_dispentry_t *linear_first(dns_qid_t *disp); -static dns_dispentry_t *linear_next(dns_qid_t *disp, - dns_dispentry_t *resp); -static void dispatch_free(dns_dispatch_t **dispp); -static isc_result_t dispatch_createudp(dns_dispatchmgr_t *mgr, - isc_socketmgr_t *sockmgr, - isc_taskmgr_t *taskmgr, - isc_sockaddr_t *localaddr, - unsigned int maxrequests, - unsigned int attributes, - dns_dispatch_t **dispp); -static isc_boolean_t destroy_mgr_ok(dns_dispatchmgr_t *mgr); -static void destroy_mgr(dns_dispatchmgr_t **mgrp); -static isc_result_t qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets, - unsigned int increment, isc_boolean_t usepool, - dns_qid_t **qidp); -static void qid_destroy(isc_mem_t *mctx, dns_qid_t **qidp); -static isc_uint16_t nsid_next(dns_nsid_t *nsid); -static isc_result_t nsid_init(isc_mem_t *mctx, dns_nsid_t *nsid, isc_boolean_t usepool); -static void nsid_destroy(isc_mem_t *mctx, dns_nsid_t *nsid); - -#define LVL(x) ISC_LOG_DEBUG(x) - -static void -mgr_log(dns_dispatchmgr_t *mgr, int level, const char *fmt, ...) - ISC_FORMAT_PRINTF(3, 4); - -static void -mgr_log(dns_dispatchmgr_t *mgr, int level, const char *fmt, ...) { - char msgbuf[2048]; - va_list ap; - - if (! isc_log_wouldlog(dns_lctx, level)) - return; - - va_start(ap, fmt); - vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); - va_end(ap); - - isc_log_write(dns_lctx, - DNS_LOGCATEGORY_DISPATCH, DNS_LOGMODULE_DISPATCH, - level, "dispatchmgr %p: %s", mgr, msgbuf); -} - -static void -dispatch_log(dns_dispatch_t *disp, int level, const char *fmt, ...) - ISC_FORMAT_PRINTF(3, 4); - -static void -dispatch_log(dns_dispatch_t *disp, int level, const char *fmt, ...) { - char msgbuf[2048]; - va_list ap; - - if (! isc_log_wouldlog(dns_lctx, level)) - return; - - va_start(ap, fmt); - vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); - va_end(ap); - - isc_log_write(dns_lctx, - DNS_LOGCATEGORY_DISPATCH, DNS_LOGMODULE_DISPATCH, - level, "dispatch %p: %s", disp, msgbuf); -} - -static void -request_log(dns_dispatch_t *disp, dns_dispentry_t *resp, - int level, const char *fmt, ...) - ISC_FORMAT_PRINTF(4, 5); - -static void -request_log(dns_dispatch_t *disp, dns_dispentry_t *resp, - int level, const char *fmt, ...) -{ - char msgbuf[2048]; - char peerbuf[256]; - va_list ap; - - if (! isc_log_wouldlog(dns_lctx, level)) - return; - - va_start(ap, fmt); - vsnprintf(msgbuf, sizeof(msgbuf), fmt, ap); - va_end(ap); - - if (VALID_RESPONSE(resp)) { - isc_sockaddr_format(&resp->host, peerbuf, sizeof(peerbuf)); - isc_log_write(dns_lctx, DNS_LOGCATEGORY_DISPATCH, - DNS_LOGMODULE_DISPATCH, level, - "dispatch %p response %p %s: %s", disp, resp, - peerbuf, msgbuf); - } else { - isc_log_write(dns_lctx, DNS_LOGCATEGORY_DISPATCH, - DNS_LOGMODULE_DISPATCH, level, - "dispatch %p req/resp %p: %s", disp, resp, - msgbuf); - } -} - -/* - * Return an unpredictable message ID. - */ -static dns_messageid_t -dns_randomid(dns_nsid_t *nsid) { - isc_uint32_t id; - - id = nsid_next(nsid); - - return ((dns_messageid_t)id); -} - -/* - * Return a hash of the destination and message id. - */ -static isc_uint32_t -dns_hash(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id) { - unsigned int ret; - - ret = isc_sockaddr_hash(dest, ISC_TRUE); - ret ^= id; - ret %= qid->qid_nbuckets; - - INSIST(ret < qid->qid_nbuckets); - - return (ret); -} - -/* - * Find the first entry in 'qid'. Returns NULL if there are no entries. - */ -static dns_dispentry_t * -linear_first(dns_qid_t *qid) { - dns_dispentry_t *ret; - unsigned int bucket; - - bucket = 0; - - while (bucket < qid->qid_nbuckets) { - ret = ISC_LIST_HEAD(qid->qid_table[bucket]); - if (ret != NULL) - return (ret); - bucket++; - } - - return (NULL); -} - -/* - * Find the next entry after 'resp' in 'qid'. Return NULL if there are - * no more entries. - */ -static dns_dispentry_t * -linear_next(dns_qid_t *qid, dns_dispentry_t *resp) { - dns_dispentry_t *ret; - unsigned int bucket; - - ret = ISC_LIST_NEXT(resp, link); - if (ret != NULL) - return (ret); - - bucket = resp->bucket; - bucket++; - while (bucket < qid->qid_nbuckets) { - ret = ISC_LIST_HEAD(qid->qid_table[bucket]); - if (ret != NULL) - return (ret); - bucket++; - } - - return (NULL); -} - -/* - * The dispatch must be locked. - */ -static isc_boolean_t -destroy_disp_ok(dns_dispatch_t *disp) -{ - if (disp->refcount != 0) - return (ISC_FALSE); - - if (disp->recv_pending != 0) - return (ISC_FALSE); - - if (disp->shutting_down == 0) - return (ISC_FALSE); - - return (ISC_TRUE); -} - - -/* - * Called when refcount reaches 0 (and safe to destroy). - * - * The dispatcher must not be locked. - * The manager must be locked. - */ -static void -destroy_disp(isc_task_t *task, isc_event_t *event) { - dns_dispatch_t *disp; - dns_dispatchmgr_t *mgr; - isc_boolean_t killmgr; - - INSIST(event->ev_type == DNS_EVENT_DISPATCHCONTROL); - - UNUSED(task); - - disp = event->ev_arg; - mgr = disp->mgr; - - LOCK(&mgr->lock); - ISC_LIST_UNLINK(mgr->list, disp, link); - - dispatch_log(disp, LVL(90), - "shutting down; detaching from sock %p, task %p", - disp->socket, disp->task); - - isc_socket_detach(&disp->socket); - isc_task_detach(&disp->task); - isc_event_free(&event); - - dispatch_free(&disp); - - killmgr = destroy_mgr_ok(mgr); - UNLOCK(&mgr->lock); - if (killmgr) - destroy_mgr(&mgr); -} - - -/* - * Find an entry for query ID 'id' and socket address 'dest' in 'qid'. - * Return NULL if no such entry exists. - */ -static dns_dispentry_t * -bucket_search(dns_qid_t *qid, isc_sockaddr_t *dest, dns_messageid_t id, - unsigned int bucket) -{ - dns_dispentry_t *res; - - REQUIRE(bucket < qid->qid_nbuckets); - - res = ISC_LIST_HEAD(qid->qid_table[bucket]); - - while (res != NULL) { - if ((res->id == id) && isc_sockaddr_equal(dest, &res->host)) - return (res); - res = ISC_LIST_NEXT(res, link); - } - - return (NULL); -} - -static void -free_buffer(dns_dispatch_t *disp, void *buf, unsigned int len) { - INSIST(buf != NULL && len != 0); - - - switch (disp->socktype) { - case isc_sockettype_tcp: - INSIST(disp->tcpbuffers > 0); - disp->tcpbuffers--; - isc_mem_put(disp->mgr->mctx, buf, len); - break; - case isc_sockettype_udp: - LOCK(&disp->mgr->buffer_lock); - INSIST(disp->mgr->buffers > 0); - INSIST(len == disp->mgr->buffersize); - disp->mgr->buffers--; - isc_mempool_put(disp->mgr->bpool, buf); - UNLOCK(&disp->mgr->buffer_lock); - break; - default: - INSIST(0); - break; - } -} - -static void * -allocate_udp_buffer(dns_dispatch_t *disp) { - void *temp; - - LOCK(&disp->mgr->buffer_lock); - temp = isc_mempool_get(disp->mgr->bpool); - - if (temp != NULL) - disp->mgr->buffers++; - UNLOCK(&disp->mgr->buffer_lock); - - return (temp); -} - -static inline void -free_event(dns_dispatch_t *disp, dns_dispatchevent_t *ev) { - if (disp->failsafe_ev == ev) { - INSIST(disp->shutdown_out == 1); - disp->shutdown_out = 0; - - return; - } - - isc_mempool_put(disp->mgr->epool, ev); -} - -static inline dns_dispatchevent_t * -allocate_event(dns_dispatch_t *disp) { - dns_dispatchevent_t *ev; - - ev = isc_mempool_get(disp->mgr->epool); - if (ev == NULL) - return (NULL); - ISC_EVENT_INIT(ev, sizeof(*ev), 0, NULL, 0, - NULL, NULL, NULL, NULL, NULL); - - return (ev); -} - -/* - * General flow: - * - * If I/O result == CANCELED or error, free the buffer. - * - * If query, free the buffer, restart. - * - * If response: - * Allocate event, fill in details. - * If cannot allocate, free buffer, restart. - * find target. If not found, free buffer, restart. - * if event queue is not empty, queue. else, send. - * restart. - */ -static void -udp_recv(isc_task_t *task, isc_event_t *ev_in) { - isc_socketevent_t *ev = (isc_socketevent_t *)ev_in; - dns_dispatch_t *disp = ev_in->ev_arg; - dns_messageid_t id; - isc_result_t dres; - isc_buffer_t source; - unsigned int flags; - dns_dispentry_t *resp; - dns_dispatchevent_t *rev; - unsigned int bucket; - isc_boolean_t killit; - isc_boolean_t queue_response; - dns_dispatchmgr_t *mgr; - dns_qid_t *qid; - isc_netaddr_t netaddr; - int match; - - UNUSED(task); - - LOCK(&disp->lock); - - mgr = disp->mgr; - qid = mgr->qid; - - dispatch_log(disp, LVL(90), - "got packet: requests %d, buffers %d, recvs %d", - disp->requests, disp->mgr->buffers, disp->recv_pending); - - if (ev->ev_type == ISC_SOCKEVENT_RECVDONE) { - /* - * Unless the receive event was imported from a listening - * interface, in which case the event type is - * DNS_EVENT_IMPORTRECVDONE, receive operation must be pending. - */ - INSIST(disp->recv_pending != 0); - disp->recv_pending = 0; - } - - if (disp->shutting_down) { - /* - * This dispatcher is shutting down. - */ - free_buffer(disp, ev->region.base, ev->region.length); - - isc_event_free(&ev_in); - ev = NULL; - - killit = destroy_disp_ok(disp); - UNLOCK(&disp->lock); - if (killit) - isc_task_send(disp->task, &disp->ctlevent); - - return; - } - - if (ev->result != ISC_R_SUCCESS) { - free_buffer(disp, ev->region.base, ev->region.length); - - if (ev->result != ISC_R_CANCELED) - dispatch_log(disp, ISC_LOG_ERROR, - "odd socket result in udp_recv(): %s", - isc_result_totext(ev->result)); - - UNLOCK(&disp->lock); - isc_event_free(&ev_in); - return; - } - - /* - * If this is from a blackholed address, drop it. - */ - isc_netaddr_fromsockaddr(&netaddr, &ev->address); - if (disp->mgr->blackhole != NULL && - dns_acl_match(&netaddr, NULL, disp->mgr->blackhole, - NULL, &match, NULL) == ISC_R_SUCCESS && - match > 0) - { - if (isc_log_wouldlog(dns_lctx, LVL(10))) { - char netaddrstr[ISC_NETADDR_FORMATSIZE]; - isc_netaddr_format(&netaddr, netaddrstr, - sizeof(netaddrstr)); - dispatch_log(disp, LVL(10), - "blackholed packet from %s", - netaddrstr); - } - free_buffer(disp, ev->region.base, ev->region.length); - goto restart; - } - - /* - * Peek into the buffer to see what we can see. - */ - isc_buffer_init(&source, ev->region.base, ev->region.length); - isc_buffer_add(&source, ev->n); - dres = dns_message_peekheader(&source, &id, &flags); - if (dres != ISC_R_SUCCESS) { - free_buffer(disp, ev->region.base, ev->region.length); - dispatch_log(disp, LVL(10), "got garbage packet"); - goto restart; - } - - dispatch_log(disp, LVL(92), - "got valid DNS message header, /QR %c, id %u", - ((flags & DNS_MESSAGEFLAG_QR) ? '1' : '0'), id); - - /* - * Look at flags. If query, drop it. If response, - * look to see where it goes. - */ - queue_response = ISC_FALSE; - if ((flags & DNS_MESSAGEFLAG_QR) == 0) { - /* query */ - free_buffer(disp, ev->region.base, ev->region.length); - goto restart; - } - - dns_dispatch_hash(&ev->timestamp, sizeof(&ev->timestamp)); - dns_dispatch_hash(ev->region.base, ev->region.length); - - /* response */ - bucket = dns_hash(qid, &ev->address, id); - LOCK(&qid->lock); - resp = bucket_search(qid, &ev->address, id, bucket); - dispatch_log(disp, LVL(90), - "search for response in bucket %d: %s", - bucket, (resp == NULL ? "not found" : "found")); - - if (resp == NULL) { - free_buffer(disp, ev->region.base, ev->region.length); - goto unlock; - } - - /* - * Now that we have the original dispatch the query was sent - * from check that the address and port the response was - * sent to make sense. - */ - if (disp != resp->disp) { - isc_sockaddr_t a1; - isc_sockaddr_t a2; - - /* - * Check that the socket types and ports match. - */ - if (disp->socktype != resp->disp->socktype || - isc_sockaddr_getport(&disp->local) != - isc_sockaddr_getport(&resp->disp->local)) { - free_buffer(disp, ev->region.base, ev->region.length); - goto unlock; - } - - /* - * If both dispatches are bound to an address then fail as - * the addresses can't be equal (enforced by the IP stack). - * - * Note under Linux a packet can be sent out via IPv4 socket - * and the response be received via a IPv6 socket. - * - * Requests sent out via IPv6 should always come back in - * via IPv6. - */ - if (isc_sockaddr_pf(&resp->disp->local) == PF_INET6 && - isc_sockaddr_pf(&disp->local) != PF_INET6) { - free_buffer(disp, ev->region.base, ev->region.length); - goto unlock; - } - isc_sockaddr_anyofpf(&a1, isc_sockaddr_pf(&resp->disp->local)); - isc_sockaddr_anyofpf(&a2, isc_sockaddr_pf(&disp->local)); - if (!isc_sockaddr_eqaddr(&a1, &resp->disp->local) && - !isc_sockaddr_eqaddr(&a2, &disp->local)) { - free_buffer(disp, ev->region.base, ev->region.length); - goto unlock; - } - } - - queue_response = resp->item_out; - rev = allocate_event(resp->disp); - if (rev == NULL) { - free_buffer(disp, ev->region.base, ev->region.length); - goto unlock; - } - - /* - * At this point, rev contains the event we want to fill in, and - * resp contains the information on the place to send it to. - * Send the event off. - */ - isc_buffer_init(&rev->buffer, ev->region.base, ev->region.length); - isc_buffer_add(&rev->buffer, ev->n); - rev->result = ISC_R_SUCCESS; - rev->id = id; - rev->addr = ev->address; - rev->pktinfo = ev->pktinfo; - rev->attributes = ev->attributes; - if (queue_response) { - ISC_LIST_APPEND(resp->items, rev, ev_link); - } else { - ISC_EVENT_INIT(rev, sizeof(*rev), 0, NULL, - DNS_EVENT_DISPATCH, - resp->action, resp->arg, resp, NULL, NULL); - request_log(disp, resp, LVL(90), - "[a] Sent event %p buffer %p len %d to task %p", - rev, rev->buffer.base, rev->buffer.length, - resp->task); - resp->item_out = ISC_TRUE; - isc_task_send(resp->task, ISC_EVENT_PTR(&rev)); - } - unlock: - UNLOCK(&qid->lock); - - /* - * Restart recv() to get the next packet. - */ - restart: - startrecv(disp); - - UNLOCK(&disp->lock); - - isc_event_free(&ev_in); -} - -/* - * General flow: - * - * If I/O result == CANCELED, EOF, or error, notify everyone as the - * various queues drain. - * - * If query, restart. - * - * If response: - * Allocate event, fill in details. - * If cannot allocate, restart. - * find target. If not found, restart. - * if event queue is not empty, queue. else, send. - * restart. - */ -static void -tcp_recv(isc_task_t *task, isc_event_t *ev_in) { - dns_dispatch_t *disp = ev_in->ev_arg; - dns_tcpmsg_t *tcpmsg = &disp->tcpmsg; - dns_messageid_t id; - isc_result_t dres; - unsigned int flags; - dns_dispentry_t *resp; - dns_dispatchevent_t *rev; - unsigned int bucket; - isc_boolean_t killit; - isc_boolean_t queue_response; - dns_qid_t *qid; - int level; - char buf[ISC_SOCKADDR_FORMATSIZE]; - - UNUSED(task); - - REQUIRE(VALID_DISPATCH(disp)); - - qid = disp->qid; - - dispatch_log(disp, LVL(90), - "got TCP packet: requests %d, buffers %d, recvs %d", - disp->requests, disp->tcpbuffers, disp->recv_pending); - - LOCK(&disp->lock); - - INSIST(disp->recv_pending != 0); - disp->recv_pending = 0; - - if (disp->refcount == 0) { - /* - * This dispatcher is shutting down. Force cancelation. - */ - tcpmsg->result = ISC_R_CANCELED; - } - - if (tcpmsg->result != ISC_R_SUCCESS) { - switch (tcpmsg->result) { - case ISC_R_CANCELED: - break; - - case ISC_R_EOF: - dispatch_log(disp, LVL(90), "shutting down on EOF"); - do_cancel(disp); - break; - - case ISC_R_CONNECTIONRESET: - level = ISC_LOG_INFO; - goto logit; - - default: - level = ISC_LOG_ERROR; - logit: - isc_sockaddr_format(&tcpmsg->address, buf, sizeof(buf)); - dispatch_log(disp, level, "shutting down due to TCP " - "receive error: %s: %s", buf, - isc_result_totext(tcpmsg->result)); - do_cancel(disp); - break; - } - - /* - * The event is statically allocated in the tcpmsg - * structure, and destroy_disp() frees the tcpmsg, so we must - * free the event *before* calling destroy_disp(). - */ - isc_event_free(&ev_in); - - disp->shutting_down = 1; - disp->shutdown_why = tcpmsg->result; - - /* - * If the recv() was canceled pass the word on. - */ - killit = destroy_disp_ok(disp); - UNLOCK(&disp->lock); - if (killit) - isc_task_send(disp->task, &disp->ctlevent); - return; - } - - dispatch_log(disp, LVL(90), "result %d, length == %d, addr = %p", - tcpmsg->result, - tcpmsg->buffer.length, tcpmsg->buffer.base); - - /* - * Peek into the buffer to see what we can see. - */ - dres = dns_message_peekheader(&tcpmsg->buffer, &id, &flags); - if (dres != ISC_R_SUCCESS) { - dispatch_log(disp, LVL(10), "got garbage packet"); - goto restart; - } - - dispatch_log(disp, LVL(92), - "got valid DNS message header, /QR %c, id %u", - ((flags & DNS_MESSAGEFLAG_QR) ? '1' : '0'), id); - - /* - * Allocate an event to send to the query or response client, and - * allocate a new buffer for our use. - */ - - /* - * Look at flags. If query, drop it. If response, - * look to see where it goes. - */ - queue_response = ISC_FALSE; - if ((flags & DNS_MESSAGEFLAG_QR) == 0) { - /* - * Query. - */ - goto restart; - } - - dns_dispatch_hash(tcpmsg->buffer.base, tcpmsg->buffer.length); - - /* - * Response. - */ - bucket = dns_hash(qid, &tcpmsg->address, id); - LOCK(&qid->lock); - resp = bucket_search(qid, &tcpmsg->address, id, bucket); - dispatch_log(disp, LVL(90), - "search for response in bucket %d: %s", - bucket, (resp == NULL ? "not found" : "found")); - - if (resp == NULL) - goto unlock; - queue_response = resp->item_out; - rev = allocate_event(disp); - if (rev == NULL) - goto unlock; - - /* - * At this point, rev contains the event we want to fill in, and - * resp contains the information on the place to send it to. - * Send the event off. - */ - dns_tcpmsg_keepbuffer(tcpmsg, &rev->buffer); - disp->tcpbuffers++; - rev->result = ISC_R_SUCCESS; - rev->id = id; - rev->addr = tcpmsg->address; - if (queue_response) { - ISC_LIST_APPEND(resp->items, rev, ev_link); - } else { - ISC_EVENT_INIT(rev, sizeof(*rev), 0, NULL, DNS_EVENT_DISPATCH, - resp->action, resp->arg, resp, NULL, NULL); - request_log(disp, resp, LVL(90), - "[b] Sent event %p buffer %p len %d to task %p", - rev, rev->buffer.base, rev->buffer.length, - resp->task); - resp->item_out = ISC_TRUE; - isc_task_send(resp->task, ISC_EVENT_PTR(&rev)); - } - unlock: - UNLOCK(&qid->lock); - - /* - * Restart recv() to get the next packet. - */ - restart: - startrecv(disp); - - UNLOCK(&disp->lock); - - isc_event_free(&ev_in); -} - -/* - * disp must be locked. - */ -static void -startrecv(dns_dispatch_t *disp) { - isc_result_t res; - isc_region_t region; - - if (disp->shutting_down == 1) - return; - - if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) - return; - - if (disp->recv_pending != 0) - return; - - if (disp->mgr->buffers >= disp->mgr->maxbuffers) - return; - - switch (disp->socktype) { - /* - * UDP reads are always maximal. - */ - case isc_sockettype_udp: - region.length = disp->mgr->buffersize; - region.base = allocate_udp_buffer(disp); - if (region.base == NULL) - return; - res = isc_socket_recv(disp->socket, ®ion, 1, - disp->task, udp_recv, disp); - if (res != ISC_R_SUCCESS) { - free_buffer(disp, region.base, region.length); - disp->shutdown_why = res; - disp->shutting_down = 1; - do_cancel(disp); - return; - } - INSIST(disp->recv_pending == 0); - disp->recv_pending = 1; - break; - - case isc_sockettype_tcp: - res = dns_tcpmsg_readmessage(&disp->tcpmsg, disp->task, - tcp_recv, disp); - if (res != ISC_R_SUCCESS) { - disp->shutdown_why = res; - disp->shutting_down = 1; - do_cancel(disp); - return; - } - INSIST(disp->recv_pending == 0); - disp->recv_pending = 1; - break; - default: - INSIST(0); - break; - } -} - -/* - * Mgr must be locked when calling this function. - */ -static isc_boolean_t -destroy_mgr_ok(dns_dispatchmgr_t *mgr) { - mgr_log(mgr, LVL(90), - "destroy_mgr_ok: shuttingdown=%d, listnonempty=%d, " - "epool=%d, rpool=%d, dpool=%d", - MGR_IS_SHUTTINGDOWN(mgr), !ISC_LIST_EMPTY(mgr->list), - isc_mempool_getallocated(mgr->epool), - isc_mempool_getallocated(mgr->rpool), - isc_mempool_getallocated(mgr->dpool)); - if (!MGR_IS_SHUTTINGDOWN(mgr)) - return (ISC_FALSE); - if (!ISC_LIST_EMPTY(mgr->list)) - return (ISC_FALSE); - if (isc_mempool_getallocated(mgr->epool) != 0) - return (ISC_FALSE); - if (isc_mempool_getallocated(mgr->rpool) != 0) - return (ISC_FALSE); - if (isc_mempool_getallocated(mgr->dpool) != 0) - return (ISC_FALSE); - - return (ISC_TRUE); -} - -/* - * Mgr must be unlocked when calling this function. - */ -static void -destroy_mgr(dns_dispatchmgr_t **mgrp) { - isc_mem_t *mctx; - dns_dispatchmgr_t *mgr; - - mgr = *mgrp; - *mgrp = NULL; - - mctx = mgr->mctx; - - mgr->magic = 0; - mgr->mctx = NULL; - DESTROYLOCK(&mgr->lock); - mgr->state = 0; - - isc_mempool_destroy(&mgr->epool); - isc_mempool_destroy(&mgr->rpool); - isc_mempool_destroy(&mgr->dpool); - isc_mempool_destroy(&mgr->bpool); - - DESTROYLOCK(&mgr->pool_lock); - - if (mgr->entropy != NULL) - isc_entropy_detach(&mgr->entropy); - if (mgr->qid != NULL) - qid_destroy(mctx, &mgr->qid); - - DESTROYLOCK(&mgr->buffer_lock); - - if (mgr->blackhole != NULL) - dns_acl_detach(&mgr->blackhole); - - if (mgr->portlist != NULL) - dns_portlist_detach(&mgr->portlist); - - isc_mem_put(mctx, mgr, sizeof(dns_dispatchmgr_t)); - isc_mem_detach(&mctx); -} - -static isc_result_t -create_socket(isc_socketmgr_t *mgr, isc_sockaddr_t *local, - isc_socket_t **sockp) -{ - isc_socket_t *sock; - isc_result_t result; - - sock = NULL; - result = isc_socket_create(mgr, isc_sockaddr_pf(local), - isc_sockettype_udp, &sock); - if (result != ISC_R_SUCCESS) - return (result); - -#ifndef ISC_ALLOW_MAPPED - isc_socket_ipv6only(sock, ISC_TRUE); -#endif - result = isc_socket_bind(sock, local); - if (result != ISC_R_SUCCESS) { - isc_socket_detach(&sock); - return (result); - } - - *sockp = sock; - return (ISC_R_SUCCESS); -} - -/* - * Publics. - */ - -isc_result_t -dns_dispatchmgr_create(isc_mem_t *mctx, isc_entropy_t *entropy, - dns_dispatchmgr_t **mgrp) -{ - dns_dispatchmgr_t *mgr; - isc_result_t result; - - REQUIRE(mctx != NULL); - REQUIRE(mgrp != NULL && *mgrp == NULL); - - mgr = isc_mem_get(mctx, sizeof(dns_dispatchmgr_t)); - if (mgr == NULL) - return (ISC_R_NOMEMORY); - - mgr->mctx = NULL; - isc_mem_attach(mctx, &mgr->mctx); - - mgr->blackhole = NULL; - mgr->portlist = NULL; - - result = isc_mutex_init(&mgr->lock); - if (result != ISC_R_SUCCESS) - goto deallocate; - - result = isc_mutex_init(&mgr->buffer_lock); - if (result != ISC_R_SUCCESS) - goto kill_lock; - - result = isc_mutex_init(&mgr->pool_lock); - if (result != ISC_R_SUCCESS) - goto kill_buffer_lock; - - mgr->epool = NULL; - if (isc_mempool_create(mgr->mctx, sizeof(dns_dispatchevent_t), - &mgr->epool) != ISC_R_SUCCESS) { - result = ISC_R_NOMEMORY; - goto kill_pool_lock; - } - - mgr->rpool = NULL; - if (isc_mempool_create(mgr->mctx, sizeof(dns_dispentry_t), - &mgr->rpool) != ISC_R_SUCCESS) { - result = ISC_R_NOMEMORY; - goto kill_epool; - } - - mgr->dpool = NULL; - if (isc_mempool_create(mgr->mctx, sizeof(dns_dispatch_t), - &mgr->dpool) != ISC_R_SUCCESS) { - result = ISC_R_NOMEMORY; - goto kill_rpool; - } - - isc_mempool_setname(mgr->epool, "dispmgr_epool"); - isc_mempool_setfreemax(mgr->epool, 1024); - isc_mempool_associatelock(mgr->epool, &mgr->pool_lock); - - isc_mempool_setname(mgr->rpool, "dispmgr_rpool"); - isc_mempool_setfreemax(mgr->rpool, 1024); - isc_mempool_associatelock(mgr->rpool, &mgr->pool_lock); - - isc_mempool_setname(mgr->dpool, "dispmgr_dpool"); - isc_mempool_setfreemax(mgr->dpool, 1024); - isc_mempool_associatelock(mgr->dpool, &mgr->pool_lock); - - mgr->buffers = 0; - mgr->buffersize = 0; - mgr->maxbuffers = 0; - mgr->bpool = NULL; - mgr->entropy = NULL; - mgr->qid = NULL; - mgr->state = 0; - ISC_LIST_INIT(mgr->list); - mgr->magic = DNS_DISPATCHMGR_MAGIC; - - if (entropy != NULL) - isc_entropy_attach(entropy, &mgr->entropy); - - *mgrp = mgr; - return (ISC_R_SUCCESS); - - kill_rpool: - isc_mempool_destroy(&mgr->rpool); - kill_epool: - isc_mempool_destroy(&mgr->epool); - kill_pool_lock: - DESTROYLOCK(&mgr->pool_lock); - kill_buffer_lock: - DESTROYLOCK(&mgr->buffer_lock); - kill_lock: - DESTROYLOCK(&mgr->lock); - deallocate: - isc_mem_put(mctx, mgr, sizeof(dns_dispatchmgr_t)); - isc_mem_detach(&mctx); - - return (result); -} - -void -dns_dispatchmgr_setblackhole(dns_dispatchmgr_t *mgr, dns_acl_t *blackhole) { - REQUIRE(VALID_DISPATCHMGR(mgr)); - if (mgr->blackhole != NULL) - dns_acl_detach(&mgr->blackhole); - dns_acl_attach(blackhole, &mgr->blackhole); -} - -dns_acl_t * -dns_dispatchmgr_getblackhole(dns_dispatchmgr_t *mgr) { - REQUIRE(VALID_DISPATCHMGR(mgr)); - return (mgr->blackhole); -} - -void -dns_dispatchmgr_setblackportlist(dns_dispatchmgr_t *mgr, - dns_portlist_t *portlist) -{ - REQUIRE(VALID_DISPATCHMGR(mgr)); - if (mgr->portlist != NULL) - dns_portlist_detach(&mgr->portlist); - if (portlist != NULL) - dns_portlist_attach(portlist, &mgr->portlist); -} - -dns_portlist_t * -dns_dispatchmgr_getblackportlist(dns_dispatchmgr_t *mgr) { - REQUIRE(VALID_DISPATCHMGR(mgr)); - return (mgr->portlist); -} - -static isc_result_t -dns_dispatchmgr_setudp(dns_dispatchmgr_t *mgr, - unsigned int buffersize, unsigned int maxbuffers, - unsigned int buckets, unsigned int increment) -{ - isc_result_t result; - - REQUIRE(VALID_DISPATCHMGR(mgr)); - REQUIRE(buffersize >= 512 && buffersize < (64 * 1024)); - REQUIRE(maxbuffers > 0); - REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ - REQUIRE(increment > buckets); - - /* - * Keep some number of items around. This should be a config - * option. For now, keep 8, but later keep at least two even - * if the caller wants less. This allows us to ensure certain - * things, like an event can be "freed" and the next allocation - * will always succeed. - * - * Note that if limits are placed on anything here, we use one - * event internally, so the actual limit should be "wanted + 1." - * - * XXXMLG - */ - - if (maxbuffers < 8) - maxbuffers = 8; - - LOCK(&mgr->buffer_lock); - if (mgr->bpool != NULL) { - isc_mempool_setmaxalloc(mgr->bpool, maxbuffers); - mgr->maxbuffers = maxbuffers; - UNLOCK(&mgr->buffer_lock); - return (ISC_R_SUCCESS); - } - - if (isc_mempool_create(mgr->mctx, buffersize, - &mgr->bpool) != ISC_R_SUCCESS) { - UNLOCK(&mgr->buffer_lock); - return (ISC_R_NOMEMORY); - } - - isc_mempool_setname(mgr->bpool, "dispmgr_bpool"); - isc_mempool_setmaxalloc(mgr->bpool, maxbuffers); - isc_mempool_associatelock(mgr->bpool, &mgr->pool_lock); - - result = qid_allocate(mgr, buckets, increment, ISC_TRUE, &mgr->qid); - if (result != ISC_R_SUCCESS) - goto cleanup; - - mgr->buffersize = buffersize; - mgr->maxbuffers = maxbuffers; - UNLOCK(&mgr->buffer_lock); - return (ISC_R_SUCCESS); - - cleanup: - isc_mempool_destroy(&mgr->bpool); - UNLOCK(&mgr->buffer_lock); - return (ISC_R_NOMEMORY); -} - -void -dns_dispatchmgr_destroy(dns_dispatchmgr_t **mgrp) { - dns_dispatchmgr_t *mgr; - isc_boolean_t killit; - - REQUIRE(mgrp != NULL); - REQUIRE(VALID_DISPATCHMGR(*mgrp)); - - mgr = *mgrp; - *mgrp = NULL; - - LOCK(&mgr->lock); - mgr->state |= MGR_SHUTTINGDOWN; - - killit = destroy_mgr_ok(mgr); - UNLOCK(&mgr->lock); - - mgr_log(mgr, LVL(90), "destroy: killit=%d", killit); - - if (killit) - destroy_mgr(&mgr); -} - -static isc_boolean_t -blacklisted(dns_dispatchmgr_t *mgr, isc_socket_t *sock) { - isc_sockaddr_t sockaddr; - isc_result_t result; - - if (mgr->portlist == NULL) - return (ISC_FALSE); - - result = isc_socket_getsockname(sock, &sockaddr); - if (result != ISC_R_SUCCESS) - return (ISC_FALSE); - - if (mgr->portlist != NULL && - dns_portlist_match(mgr->portlist, isc_sockaddr_pf(&sockaddr), - isc_sockaddr_getport(&sockaddr))) - return (ISC_TRUE); - return (ISC_FALSE); -} - -#define ATTRMATCH(_a1, _a2, _mask) (((_a1) & (_mask)) == ((_a2) & (_mask))) - -static isc_boolean_t -local_addr_match(dns_dispatch_t *disp, isc_sockaddr_t *addr) { - isc_sockaddr_t sockaddr; - isc_result_t result; - - if (addr == NULL) - return (ISC_TRUE); - - /* - * Don't match wildcard ports against newly blacklisted ports. - */ - if (disp->mgr->portlist != NULL && - isc_sockaddr_getport(addr) == 0 && - isc_sockaddr_getport(&disp->local) == 0 && - blacklisted(disp->mgr, disp->socket)) - return (ISC_FALSE); - - /* - * Check if we match the binding <address,port>. - * Wildcard ports match/fail here. - */ - if (isc_sockaddr_equal(&disp->local, addr)) - return (ISC_TRUE); - if (isc_sockaddr_getport(addr) == 0) - return (ISC_FALSE); - - /* - * Check if we match a bound wildcard port <address,port>. - */ - if (!isc_sockaddr_eqaddr(&disp->local, addr)) - return (ISC_FALSE); - result = isc_socket_getsockname(disp->socket, &sockaddr); - if (result != ISC_R_SUCCESS) - return (ISC_FALSE); - - return (isc_sockaddr_equal(&sockaddr, addr)); -} - -/* - * Requires mgr be locked. - * - * No dispatcher can be locked by this thread when calling this function. - * - * - * NOTE: - * If a matching dispatcher is found, it is locked after this function - * returns, and must be unlocked by the caller. - */ -static isc_result_t -dispatch_find(dns_dispatchmgr_t *mgr, isc_sockaddr_t *local, - unsigned int attributes, unsigned int mask, - dns_dispatch_t **dispp) -{ - dns_dispatch_t *disp; - isc_result_t result; - - /* - * Make certain that we will not match a private dispatch. - */ - attributes &= ~DNS_DISPATCHATTR_PRIVATE; - mask |= DNS_DISPATCHATTR_PRIVATE; - - disp = ISC_LIST_HEAD(mgr->list); - while (disp != NULL) { - LOCK(&disp->lock); - if ((disp->shutting_down == 0) - && ATTRMATCH(disp->attributes, attributes, mask) - && local_addr_match(disp, local)) - break; - UNLOCK(&disp->lock); - disp = ISC_LIST_NEXT(disp, link); - } - - if (disp == NULL) { - result = ISC_R_NOTFOUND; - goto out; - } - - *dispp = disp; - result = ISC_R_SUCCESS; - out: - - return (result); -} - -static isc_result_t -qid_allocate(dns_dispatchmgr_t *mgr, unsigned int buckets, - unsigned int increment, isc_boolean_t usepool, dns_qid_t **qidp) -{ - dns_qid_t *qid; - unsigned int i; - isc_result_t result; - - REQUIRE(VALID_DISPATCHMGR(mgr)); - REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ - REQUIRE(increment > buckets); - REQUIRE(qidp != NULL && *qidp == NULL); - - qid = isc_mem_get(mgr->mctx, sizeof(*qid)); - if (qid == NULL) - return (ISC_R_NOMEMORY); - - qid->qid_table = isc_mem_get(mgr->mctx, - buckets * sizeof(dns_displist_t)); - if (qid->qid_table == NULL) { - isc_mem_put(mgr->mctx, qid, sizeof(*qid)); - return (ISC_R_NOMEMORY); - } - - result = nsid_init(mgr->mctx, &qid->nsid, usepool); - if (result != ISC_R_SUCCESS) { - isc_mem_put(mgr->mctx, qid->qid_table, - buckets * sizeof(dns_displist_t)); - isc_mem_put(mgr->mctx, qid, sizeof(*qid)); - return (ISC_R_NOMEMORY); - } - - result = isc_mutex_init(&qid->lock); - if (result != ISC_R_SUCCESS) { - nsid_destroy(mgr->mctx, &qid->nsid); - isc_mem_put(mgr->mctx, qid->qid_table, - buckets * sizeof(dns_displist_t)); - isc_mem_put(mgr->mctx, qid, sizeof(*qid)); - return (result); - } - - for (i = 0; i < buckets; i++) - ISC_LIST_INIT(qid->qid_table[i]); - - qid->qid_nbuckets = buckets; - qid->qid_increment = increment; - qid->magic = QID_MAGIC; - *qidp = qid; - return (ISC_R_SUCCESS); -} - -static void -qid_destroy(isc_mem_t *mctx, dns_qid_t **qidp) { - dns_qid_t *qid; - - REQUIRE(qidp != NULL); - qid = *qidp; - - REQUIRE(VALID_QID(qid)); - - *qidp = NULL; - qid->magic = 0; - nsid_destroy(mctx, &qid->nsid); - isc_mem_put(mctx, qid->qid_table, - qid->qid_nbuckets * sizeof(dns_displist_t)); - DESTROYLOCK(&qid->lock); - isc_mem_put(mctx, qid, sizeof(*qid)); -} - -/* - * Allocate and set important limits. - */ -static isc_result_t -dispatch_allocate(dns_dispatchmgr_t *mgr, unsigned int maxrequests, - dns_dispatch_t **dispp) -{ - dns_dispatch_t *disp; - isc_result_t result; - - REQUIRE(VALID_DISPATCHMGR(mgr)); - REQUIRE(dispp != NULL && *dispp == NULL); - - /* - * Set up the dispatcher, mostly. Don't bother setting some of - * the options that are controlled by tcp vs. udp, etc. - */ - - disp = isc_mempool_get(mgr->dpool); - if (disp == NULL) - return (ISC_R_NOMEMORY); - - disp->magic = 0; - disp->mgr = mgr; - disp->maxrequests = maxrequests; - disp->attributes = 0; - ISC_LINK_INIT(disp, link); - disp->refcount = 1; - disp->recv_pending = 0; - memset(&disp->local, 0, sizeof(disp->local)); - disp->shutting_down = 0; - disp->shutdown_out = 0; - disp->connected = 0; - disp->tcpmsg_valid = 0; - disp->shutdown_why = ISC_R_UNEXPECTED; - disp->requests = 0; - disp->tcpbuffers = 0; - disp->qid = NULL; - - result = isc_mutex_init(&disp->lock); - if (result != ISC_R_SUCCESS) - goto deallocate; - - disp->failsafe_ev = allocate_event(disp); - if (disp->failsafe_ev == NULL) { - result = ISC_R_NOMEMORY; - goto kill_lock; - } - - disp->magic = DISPATCH_MAGIC; - - *dispp = disp; - return (ISC_R_SUCCESS); - - /* - * error returns - */ - kill_lock: - DESTROYLOCK(&disp->lock); - deallocate: - isc_mempool_put(mgr->dpool, disp); - - return (result); -} - - -/* - * MUST be unlocked, and not used by anthing. - */ -static void -dispatch_free(dns_dispatch_t **dispp) -{ - dns_dispatch_t *disp; - dns_dispatchmgr_t *mgr; - - REQUIRE(VALID_DISPATCH(*dispp)); - disp = *dispp; - *dispp = NULL; - - mgr = disp->mgr; - REQUIRE(VALID_DISPATCHMGR(mgr)); - - if (disp->tcpmsg_valid) { - dns_tcpmsg_invalidate(&disp->tcpmsg); - disp->tcpmsg_valid = 0; - } - - INSIST(disp->tcpbuffers == 0); - INSIST(disp->requests == 0); - INSIST(disp->recv_pending == 0); - - isc_mempool_put(mgr->epool, disp->failsafe_ev); - disp->failsafe_ev = NULL; - - if (disp->qid != NULL) - qid_destroy(mgr->mctx, &disp->qid); - disp->mgr = NULL; - DESTROYLOCK(&disp->lock); - disp->magic = 0; - isc_mempool_put(mgr->dpool, disp); -} - -isc_result_t -dns_dispatch_createtcp(dns_dispatchmgr_t *mgr, isc_socket_t *sock, - isc_taskmgr_t *taskmgr, unsigned int buffersize, - unsigned int maxbuffers, unsigned int maxrequests, - unsigned int buckets, unsigned int increment, - unsigned int attributes, dns_dispatch_t **dispp) -{ - isc_result_t result; - dns_dispatch_t *disp; - - UNUSED(maxbuffers); - UNUSED(buffersize); - - REQUIRE(VALID_DISPATCHMGR(mgr)); - REQUIRE(isc_socket_gettype(sock) == isc_sockettype_tcp); - REQUIRE((attributes & DNS_DISPATCHATTR_TCP) != 0); - REQUIRE((attributes & DNS_DISPATCHATTR_UDP) == 0); - - attributes |= DNS_DISPATCHATTR_PRIVATE; /* XXXMLG */ - - LOCK(&mgr->lock); - - /* - * dispatch_allocate() checks mgr for us. - * qid_allocate() checks buckets and increment for us. - */ - disp = NULL; - result = dispatch_allocate(mgr, maxrequests, &disp); - if (result != ISC_R_SUCCESS) { - UNLOCK(&mgr->lock); - return (result); - } - - result = qid_allocate(mgr, buckets, increment, ISC_FALSE, &disp->qid); - if (result != ISC_R_SUCCESS) - goto deallocate_dispatch; - - disp->socktype = isc_sockettype_tcp; - disp->socket = NULL; - isc_socket_attach(sock, &disp->socket); - - disp->task = NULL; - result = isc_task_create(taskmgr, 0, &disp->task); - if (result != ISC_R_SUCCESS) - goto kill_socket; - - disp->ctlevent = isc_event_allocate(mgr->mctx, disp, - DNS_EVENT_DISPATCHCONTROL, - destroy_disp, disp, - sizeof(isc_event_t)); - if (disp->ctlevent == NULL) { - result = ISC_R_NOMEMORY; - goto kill_task; - } - - isc_task_setname(disp->task, "tcpdispatch", disp); - - dns_tcpmsg_init(mgr->mctx, disp->socket, &disp->tcpmsg); - disp->tcpmsg_valid = 1; - - disp->attributes = attributes; - - /* - * Append it to the dispatcher list. - */ - ISC_LIST_APPEND(mgr->list, disp, link); - UNLOCK(&mgr->lock); - - mgr_log(mgr, LVL(90), "created TCP dispatcher %p", disp); - dispatch_log(disp, LVL(90), "created task %p", disp->task); - - *dispp = disp; - - return (ISC_R_SUCCESS); - - /* - * Error returns. - */ - kill_task: - isc_task_detach(&disp->task); - kill_socket: - isc_socket_detach(&disp->socket); - deallocate_dispatch: - dispatch_free(&disp); - - UNLOCK(&mgr->lock); - - return (result); -} - -isc_result_t -dns_dispatch_getudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr, - isc_taskmgr_t *taskmgr, isc_sockaddr_t *localaddr, - unsigned int buffersize, - unsigned int maxbuffers, unsigned int maxrequests, - unsigned int buckets, unsigned int increment, - unsigned int attributes, unsigned int mask, - dns_dispatch_t **dispp) -{ - isc_result_t result; - dns_dispatch_t *disp; - - REQUIRE(VALID_DISPATCHMGR(mgr)); - REQUIRE(sockmgr != NULL); - REQUIRE(localaddr != NULL); - REQUIRE(taskmgr != NULL); - REQUIRE(buffersize >= 512 && buffersize < (64 * 1024)); - REQUIRE(maxbuffers > 0); - REQUIRE(buckets < 2097169); /* next prime > 65536 * 32 */ - REQUIRE(increment > buckets); - REQUIRE(dispp != NULL && *dispp == NULL); - REQUIRE((attributes & DNS_DISPATCHATTR_TCP) == 0); - - result = dns_dispatchmgr_setudp(mgr, buffersize, maxbuffers, - buckets, increment); - if (result != ISC_R_SUCCESS) - return (result); - - LOCK(&mgr->lock); - - /* - * First, see if we have a dispatcher that matches. - */ - disp = NULL; - result = dispatch_find(mgr, localaddr, attributes, mask, &disp); - if (result == ISC_R_SUCCESS) { - disp->refcount++; - - if (disp->maxrequests < maxrequests) - disp->maxrequests = maxrequests; - - if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) == 0 && - (attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) - { - disp->attributes |= DNS_DISPATCHATTR_NOLISTEN; - if (disp->recv_pending != 0) - isc_socket_cancel(disp->socket, disp->task, - ISC_SOCKCANCEL_RECV); - } - - UNLOCK(&disp->lock); - UNLOCK(&mgr->lock); - - *dispp = disp; - - return (ISC_R_SUCCESS); - } - - /* - * Nope, create one. - */ - result = dispatch_createudp(mgr, sockmgr, taskmgr, localaddr, - maxrequests, attributes, &disp); - if (result != ISC_R_SUCCESS) { - UNLOCK(&mgr->lock); - return (result); - } - - UNLOCK(&mgr->lock); - *dispp = disp; - return (ISC_R_SUCCESS); -} - -/* - * mgr should be locked. - */ - -#ifndef DNS_DISPATCH_HELD -#define DNS_DISPATCH_HELD 20U -#endif - -static isc_result_t -dispatch_createudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr, - isc_taskmgr_t *taskmgr, - isc_sockaddr_t *localaddr, - unsigned int maxrequests, - unsigned int attributes, - dns_dispatch_t **dispp) -{ - isc_result_t result; - dns_dispatch_t *disp; - isc_socket_t *sock = NULL; - isc_socket_t *held[DNS_DISPATCH_HELD]; - unsigned int i = 0, j = 0; - - /* - * dispatch_allocate() checks mgr for us. - */ - disp = NULL; - result = dispatch_allocate(mgr, maxrequests, &disp); - if (result != ISC_R_SUCCESS) - return (result); - - /* - * Try to allocate a socket that is not on the blacklist. - * Hold up to DNS_DISPATCH_HELD sockets to prevent the OS - * from returning the same port to us too quickly. - */ - memset(held, 0, sizeof(held)); - getsocket: - result = create_socket(sockmgr, localaddr, &sock); - if (result != ISC_R_SUCCESS) - goto deallocate_dispatch; - if (isc_sockaddr_getport(localaddr) == 0 && blacklisted(mgr, sock)) { - if (held[i] != NULL) - isc_socket_detach(&held[i]); - held[i++] = sock; - sock = NULL; - if (i == DNS_DISPATCH_HELD) - i = 0; - if (j++ == 0xffffU) { - mgr_log(mgr, ISC_LOG_ERROR, "avoid-v%s-udp-ports: " - "unable to allocate a non-blacklisted port", - isc_sockaddr_pf(localaddr) == AF_INET ? - "4" : "6"); - result = ISC_R_FAILURE; - goto deallocate_dispatch; - } - goto getsocket; - } - - disp->socktype = isc_sockettype_udp; - disp->socket = sock; - disp->local = *localaddr; - - disp->task = NULL; - result = isc_task_create(taskmgr, 0, &disp->task); - if (result != ISC_R_SUCCESS) - goto kill_socket; - - disp->ctlevent = isc_event_allocate(mgr->mctx, disp, - DNS_EVENT_DISPATCHCONTROL, - destroy_disp, disp, - sizeof(isc_event_t)); - if (disp->ctlevent == NULL) { - result = ISC_R_NOMEMORY; - goto kill_task; - } - - isc_task_setname(disp->task, "udpdispatch", disp); - - attributes &= ~DNS_DISPATCHATTR_TCP; - attributes |= DNS_DISPATCHATTR_UDP; - disp->attributes = attributes; - - /* - * Append it to the dispatcher list. - */ - ISC_LIST_APPEND(mgr->list, disp, link); - - mgr_log(mgr, LVL(90), "created UDP dispatcher %p", disp); - dispatch_log(disp, LVL(90), "created task %p", disp->task); - dispatch_log(disp, LVL(90), "created socket %p", disp->socket); - - *dispp = disp; - - goto cleanheld; - - /* - * Error returns. - */ - kill_task: - isc_task_detach(&disp->task); - kill_socket: - isc_socket_detach(&disp->socket); - deallocate_dispatch: - dispatch_free(&disp); - cleanheld: - for (i = 0; i < DNS_DISPATCH_HELD; i++) - if (held[i] != NULL) - isc_socket_detach(&held[i]); - return (result); -} - -void -dns_dispatch_attach(dns_dispatch_t *disp, dns_dispatch_t **dispp) { - REQUIRE(VALID_DISPATCH(disp)); - REQUIRE(dispp != NULL && *dispp == NULL); - - LOCK(&disp->lock); - disp->refcount++; - UNLOCK(&disp->lock); - - *dispp = disp; -} - -/* - * It is important to lock the manager while we are deleting the dispatch, - * since dns_dispatch_getudp will call dispatch_find, which returns to - * the caller a dispatch but does not attach to it until later. _getudp - * locks the manager, however, so locking it here will keep us from attaching - * to a dispatcher that is in the process of going away. - */ -void -dns_dispatch_detach(dns_dispatch_t **dispp) { - dns_dispatch_t *disp; - isc_boolean_t killit; - - REQUIRE(dispp != NULL && VALID_DISPATCH(*dispp)); - - disp = *dispp; - *dispp = NULL; - - LOCK(&disp->lock); - - INSIST(disp->refcount > 0); - disp->refcount--; - killit = ISC_FALSE; - if (disp->refcount == 0) { - if (disp->recv_pending > 0) - isc_socket_cancel(disp->socket, disp->task, - ISC_SOCKCANCEL_RECV); - disp->shutting_down = 1; - } - - dispatch_log(disp, LVL(90), "detach: refcount %d", disp->refcount); - - killit = destroy_disp_ok(disp); - UNLOCK(&disp->lock); - if (killit) - isc_task_send(disp->task, &disp->ctlevent); -} - -isc_result_t -dns_dispatch_addresponse(dns_dispatch_t *disp, isc_sockaddr_t *dest, - isc_task_t *task, isc_taskaction_t action, void *arg, - dns_messageid_t *idp, dns_dispentry_t **resp) -{ - dns_dispentry_t *res; - unsigned int bucket; - dns_messageid_t id; - int i; - isc_boolean_t ok; - dns_qid_t *qid; - - REQUIRE(VALID_DISPATCH(disp)); - REQUIRE(task != NULL); - REQUIRE(dest != NULL); - REQUIRE(resp != NULL && *resp == NULL); - REQUIRE(idp != NULL); - - LOCK(&disp->lock); - - if (disp->shutting_down == 1) { - UNLOCK(&disp->lock); - return (ISC_R_SHUTTINGDOWN); - } - - if (disp->requests >= disp->maxrequests) { - UNLOCK(&disp->lock); - return (ISC_R_QUOTA); - } - - /* - * Try somewhat hard to find an unique ID. - */ - qid = DNS_QID(disp); - LOCK(&qid->lock); - id = dns_randomid(&qid->nsid); - bucket = dns_hash(qid, dest, id); - ok = ISC_FALSE; - for (i = 0; i < 64; i++) { - if (bucket_search(qid, dest, id, bucket) == NULL) { - ok = ISC_TRUE; - break; - } - id += qid->qid_increment; - id &= 0x0000ffff; - bucket = dns_hash(qid, dest, id); - } - - if (!ok) { - UNLOCK(&qid->lock); - UNLOCK(&disp->lock); - return (ISC_R_NOMORE); - } - - res = isc_mempool_get(disp->mgr->rpool); - if (res == NULL) { - UNLOCK(&qid->lock); - UNLOCK(&disp->lock); - return (ISC_R_NOMEMORY); - } - - disp->refcount++; - disp->requests++; - res->task = NULL; - isc_task_attach(task, &res->task); - res->disp = disp; - res->id = id; - res->bucket = bucket; - res->host = *dest; - res->action = action; - res->arg = arg; - res->item_out = ISC_FALSE; - ISC_LIST_INIT(res->items); - ISC_LINK_INIT(res, link); - res->magic = RESPONSE_MAGIC; - ISC_LIST_APPEND(qid->qid_table[bucket], res, link); - UNLOCK(&qid->lock); - - request_log(disp, res, LVL(90), - "attached to task %p", res->task); - - if (((disp->attributes & DNS_DISPATCHATTR_UDP) != 0) || - ((disp->attributes & DNS_DISPATCHATTR_CONNECTED) != 0)) - startrecv(disp); - - UNLOCK(&disp->lock); - - *idp = id; - *resp = res; - - return (ISC_R_SUCCESS); -} - -void -dns_dispatch_starttcp(dns_dispatch_t *disp) { - - REQUIRE(VALID_DISPATCH(disp)); - - dispatch_log(disp, LVL(90), "starttcp %p", disp->task); - - LOCK(&disp->lock); - disp->attributes |= DNS_DISPATCHATTR_CONNECTED; - startrecv(disp); - UNLOCK(&disp->lock); -} - -void -dns_dispatch_removeresponse(dns_dispentry_t **resp, - dns_dispatchevent_t **sockevent) -{ - dns_dispatchmgr_t *mgr; - dns_dispatch_t *disp; - dns_dispentry_t *res; - dns_dispatchevent_t *ev; - unsigned int bucket; - isc_boolean_t killit; - unsigned int n; - isc_eventlist_t events; - dns_qid_t *qid; - - REQUIRE(resp != NULL); - REQUIRE(VALID_RESPONSE(*resp)); - - res = *resp; - *resp = NULL; - - disp = res->disp; - REQUIRE(VALID_DISPATCH(disp)); - mgr = disp->mgr; - REQUIRE(VALID_DISPATCHMGR(mgr)); - - qid = DNS_QID(disp); - - if (sockevent != NULL) { - REQUIRE(*sockevent != NULL); - ev = *sockevent; - *sockevent = NULL; - } else { - ev = NULL; - } - - LOCK(&disp->lock); - - INSIST(disp->requests > 0); - disp->requests--; - INSIST(disp->refcount > 0); - disp->refcount--; - killit = ISC_FALSE; - if (disp->refcount == 0) { - if (disp->recv_pending > 0) - isc_socket_cancel(disp->socket, disp->task, - ISC_SOCKCANCEL_RECV); - disp->shutting_down = 1; - } - - bucket = res->bucket; - - LOCK(&qid->lock); - ISC_LIST_UNLINK(qid->qid_table[bucket], res, link); - UNLOCK(&qid->lock); - - if (ev == NULL && res->item_out) { - /* - * We've posted our event, but the caller hasn't gotten it - * yet. Take it back. - */ - ISC_LIST_INIT(events); - n = isc_task_unsend(res->task, res, DNS_EVENT_DISPATCH, - NULL, &events); - /* - * We had better have gotten it back. - */ - INSIST(n == 1); - ev = (dns_dispatchevent_t *)ISC_LIST_HEAD(events); - } - - if (ev != NULL) { - REQUIRE(res->item_out == ISC_TRUE); - res->item_out = ISC_FALSE; - if (ev->buffer.base != NULL) - free_buffer(disp, ev->buffer.base, ev->buffer.length); - free_event(disp, ev); - } - - request_log(disp, res, LVL(90), "detaching from task %p", res->task); - isc_task_detach(&res->task); - - /* - * Free any buffered requests as well - */ - ev = ISC_LIST_HEAD(res->items); - while (ev != NULL) { - ISC_LIST_UNLINK(res->items, ev, ev_link); - if (ev->buffer.base != NULL) - free_buffer(disp, ev->buffer.base, ev->buffer.length); - free_event(disp, ev); - ev = ISC_LIST_HEAD(res->items); - } - res->magic = 0; - isc_mempool_put(disp->mgr->rpool, res); - if (disp->shutting_down == 1) - do_cancel(disp); - else - startrecv(disp); - - killit = destroy_disp_ok(disp); - UNLOCK(&disp->lock); - if (killit) - isc_task_send(disp->task, &disp->ctlevent); -} - -static void -do_cancel(dns_dispatch_t *disp) { - dns_dispatchevent_t *ev; - dns_dispentry_t *resp; - dns_qid_t *qid; - - if (disp->shutdown_out == 1) - return; - - qid = DNS_QID(disp); - - /* - * Search for the first response handler without packets outstanding. - */ - LOCK(&qid->lock); - for (resp = linear_first(qid); - resp != NULL && resp->item_out != ISC_FALSE; - /* Empty. */) - resp = linear_next(qid, resp); - /* - * No one to send the cancel event to, so nothing to do. - */ - if (resp == NULL) - goto unlock; - - /* - * Send the shutdown failsafe event to this resp. - */ - ev = disp->failsafe_ev; - ISC_EVENT_INIT(ev, sizeof(*ev), 0, NULL, DNS_EVENT_DISPATCH, - resp->action, resp->arg, resp, NULL, NULL); - ev->result = disp->shutdown_why; - ev->buffer.base = NULL; - ev->buffer.length = 0; - disp->shutdown_out = 1; - request_log(disp, resp, LVL(10), - "cancel: failsafe event %p -> task %p", - ev, resp->task); - resp->item_out = ISC_TRUE; - isc_task_send(resp->task, ISC_EVENT_PTR(&ev)); - unlock: - UNLOCK(&qid->lock); -} - -isc_socket_t * -dns_dispatch_getsocket(dns_dispatch_t *disp) { - REQUIRE(VALID_DISPATCH(disp)); - - return (disp->socket); -} - -isc_result_t -dns_dispatch_getlocaladdress(dns_dispatch_t *disp, isc_sockaddr_t *addrp) { - - REQUIRE(VALID_DISPATCH(disp)); - REQUIRE(addrp != NULL); - - if (disp->socktype == isc_sockettype_udp) { - *addrp = disp->local; - return (ISC_R_SUCCESS); - } - return (ISC_R_NOTIMPLEMENTED); -} - -void -dns_dispatch_cancel(dns_dispatch_t *disp) { - REQUIRE(VALID_DISPATCH(disp)); - - LOCK(&disp->lock); - - if (disp->shutting_down == 1) { - UNLOCK(&disp->lock); - return; - } - - disp->shutdown_why = ISC_R_CANCELED; - disp->shutting_down = 1; - do_cancel(disp); - - UNLOCK(&disp->lock); - - return; -} - -void -dns_dispatch_changeattributes(dns_dispatch_t *disp, - unsigned int attributes, unsigned int mask) -{ - REQUIRE(VALID_DISPATCH(disp)); - - /* XXXMLG - * Should check for valid attributes here! - */ - - LOCK(&disp->lock); - - if ((mask & DNS_DISPATCHATTR_NOLISTEN) != 0) { - if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0 && - (attributes & DNS_DISPATCHATTR_NOLISTEN) == 0) { - disp->attributes &= ~DNS_DISPATCHATTR_NOLISTEN; - startrecv(disp); - } else if ((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) - == 0 && - (attributes & DNS_DISPATCHATTR_NOLISTEN) != 0) { - disp->attributes |= DNS_DISPATCHATTR_NOLISTEN; - if (disp->recv_pending != 0) - isc_socket_cancel(disp->socket, disp->task, - ISC_SOCKCANCEL_RECV); - } - } - - disp->attributes &= ~mask; - disp->attributes |= (attributes & mask); - UNLOCK(&disp->lock); -} - -void -dns_dispatch_importrecv(dns_dispatch_t *disp, isc_event_t *event) { - void *buf; - isc_socketevent_t *sevent, *newsevent; - - REQUIRE(VALID_DISPATCH(disp)); - REQUIRE((disp->attributes & DNS_DISPATCHATTR_NOLISTEN) != 0); - REQUIRE(event != NULL); - - sevent = (isc_socketevent_t *)event; - - INSIST(sevent->n <= disp->mgr->buffersize); - newsevent = (isc_socketevent_t *) - isc_event_allocate(disp->mgr->mctx, NULL, - DNS_EVENT_IMPORTRECVDONE, udp_recv, - disp, sizeof(isc_socketevent_t)); - if (newsevent == NULL) - return; - - buf = allocate_udp_buffer(disp); - if (buf == NULL) { - isc_event_free(ISC_EVENT_PTR(&newsevent)); - return; - } - memcpy(buf, sevent->region.base, sevent->n); - newsevent->region.base = buf; - newsevent->region.length = disp->mgr->buffersize; - newsevent->n = sevent->n; - newsevent->result = sevent->result; - newsevent->address = sevent->address; - newsevent->timestamp = sevent->timestamp; - newsevent->pktinfo = sevent->pktinfo; - newsevent->attributes = sevent->attributes; - - isc_task_send(disp->task, ISC_EVENT_PTR(&newsevent)); -} - -#if 0 -void -dns_dispatchmgr_dump(dns_dispatchmgr_t *mgr) { - dns_dispatch_t *disp; - char foo[1024]; - - disp = ISC_LIST_HEAD(mgr->list); - while (disp != NULL) { - isc_sockaddr_format(&disp->local, foo, sizeof(foo)); - printf("\tdispatch %p, addr %s\n", disp, foo); - disp = ISC_LIST_NEXT(disp, link); - } -} -#endif - -/* - * Allow the user to pick one of two ID randomization algorithms. - * - * The first algorithm is an adaptation of the sequence shuffling - * algorithm discovered by Carter Bays and S. D. Durham [ACM Trans. Math. - * Software 2 (1976), 59-64], as documented as Algorithm B in Chapter - * 3.2.2 in Volume 2 of Knuth's "The Art of Computer Programming". We use - * a randomly selected linear congruential random number generator with a - * modulus of 2^16, whose increment is a randomly picked odd number, and - * whose multiplier is picked from a set which meets the following - * criteria: - * Is of the form 8*n+5, which ensures "high potency" according to - * principle iii in the summary chapter 3.6. This form also has a - * gcd(a-1,m) of 4 which is good according to principle iv. - * - * Is between 0.01 and 0.99 times the modulus as specified by - * principle iv. - * - * Passes the spectral test "with flying colors" (ut >= 1) in - * dimensions 2 through 6 as calculated by Algorithm S in Chapter - * 3.3.4 and the ratings calculated by formula 35 in section E. - * - * Of the multipliers that pass this test, pick the set that is - * best according to the theoretical bounds of the serial - * correlation test. This was calculated using a simplified - * version of Knuth's Theorem K in Chapter 3.3.3. - * - * These criteria may not be important for this use, but we might as well - * pick from the best generators since there are so many possible ones and - * we don't have that many random bits to do the picking. - * - * We use a modulus of 2^16 instead of something bigger so that we will - * tend to cycle through all the possible IDs before repeating any, - * however the shuffling will perturb this somewhat. Theoretically there - * is no minimimum interval between two uses of the same ID, but in - * practice it seems to be >64000. - * - * Our adaptatation of Algorithm B mixes the hash state which has - * captured various random events into the shuffler to perturb the - * sequence. - * - * One disadvantage of this algorithm is that if the generator parameters - * were to be guessed, it would be possible to mount a limited brute force - * attack on the ID space since the IDs are only shuffled within a limited - * range. - * - * The second algorithm uses the same random number generator to populate - * a pool of 65536 IDs. The hash state is used to pick an ID from a window - * of 4096 IDs in this pool, then the chosen ID is swapped with the ID - * at the beginning of the window and the window position is advanced. - * This means that the interval between uses of the ID will be no less - * than 65536-4096. The ID sequence in the pool will become more random - * over time. - * - * For both algorithms, two more linear congruential random number generators - * are selected. The ID from the first part of algorithm is used to seed - * the first of these generators, and its output is used to seed the second. - * The strategy is use these generators as 1 to 1 hashes to obfuscate the - * properties of the generator used in the first part of either algorithm. - * - * The first algorithm may be suitable for use in a client resolver since - * its memory requirements are fairly low and it's pretty random out of - * the box. It is somewhat succeptible to a limited brute force attack, - * so the second algorithm is probably preferable for a longer running - * program that issues a large number of queries and has time to randomize - * the pool. - */ - -#define NSID_SHUFFLE_TABLE_SIZE 100 /* Suggested by Knuth */ -/* - * Pick one of the next 4096 IDs in the pool. - * There is a tradeoff here between randomness and how often and ID is reused. - */ -#define NSID_LOOKAHEAD 4096 /* Must be a power of 2 */ -#define NSID_SHUFFLE_ONLY 1 /* algorithm 1 */ -#define NSID_USE_POOL 2 /* algorithm 2 */ -#define NSID_HASHSHIFT 3 -#define NSID_HASHROTATE(v) \ - (((v) << NSID_HASHSHIFT) | ((v) >> ((sizeof(v) * 8) - NSID_HASHSHIFT))) - -static isc_uint32_t nsid_hash_state; - -/* - * Keep a running hash of various bits of data that we'll use to - * stir the ID pool or perturb the ID generator - */ -static void -nsid_hash(void *data, size_t len) { - unsigned char *p = data; - /* - * Hash function similar to the one we use for hashing names. - * We don't fold case or toss the upper bit here, though. - * This hash doesn't do much interesting when fed binary zeros, - * so there may be a better hash function. - * This function doesn't need to be very strong since we're - * only using it to stir the pool, but it should be reasonably - * fast. - */ - /* - * We don't care about locking access to nsid_hash_state. - * In fact races make the result even more non deteministic. - */ - while (len-- > 0U) { - nsid_hash_state = NSID_HASHROTATE(nsid_hash_state); - nsid_hash_state += *p++; - } -} - -/* - * Table of good linear congruential multipliers for modulus 2^16 - * in order of increasing serial correlation bounds (so trim from - * the end). - */ -static const isc_uint16_t nsid_multiplier_table[] = { - 17565, 25013, 11733, 19877, 23989, 23997, 24997, 25421, - 26781, 27413, 35901, 35917, 35973, 36229, 38317, 38437, - 39941, 40493, 41853, 46317, 50581, 51429, 53453, 53805, - 11317, 11789, 12045, 12413, 14277, 14821, 14917, 18989, - 19821, 23005, 23533, 23573, 23693, 27549, 27709, 28461, - 29365, 35605, 37693, 37757, 38309, 41285, 45261, 47061, - 47269, 48133, 48597, 50277, 50717, 50757, 50805, 51341, - 51413, 51581, 51597, 53445, 11493, 14229, 20365, 20653, - 23485, 25541, 27429, 29421, 30173, 35445, 35653, 36789, - 36797, 37109, 37157, 37669, 38661, 39773, 40397, 41837, - 41877, 45293, 47277, 47845, 49853, 51085, 51349, 54085, - 56933, 8877, 8973, 9885, 11365, 11813, 13581, 13589, - 13613, 14109, 14317, 15765, 15789, 16925, 17069, 17205, - 17621, 17941, 19077, 19381, 20245, 22845, 23733, 24869, - 25453, 27213, 28381, 28965, 29245, 29997, 30733, 30901, - 34877, 35485, 35613, 36133, 36661, 36917, 38597, 40285, - 40693, 41413, 41541, 41637, 42053, 42349, 45245, 45469, - 46493, 48205, 48613, 50861, 51861, 52877, 53933, 54397, - 55669, 56453, 56965, 58021, 7757, 7781, 8333, 9661, - 12229, 14373, 14453, 17549, 18141, 19085, 20773, 23701, - 24205, 24333, 25261, 25317, 27181, 30117, 30477, 34757, - 34885, 35565, 35885, 36541, 37957, 39733, 39813, 41157, - 41893, 42317, 46621, 48117, 48181, 49525, 55261, 55389, - 56845, 7045, 7749, 7965, 8469, 9133, 9549, 9789, - 10173, 11181, 11285, 12253, 13453, 13533, 13757, 14477, - 15053, 16901, 17213, 17269, 17525, 17629, 18605, 19013, - 19829, 19933, 20069, 20093, 23261, 23333, 24949, 25309, - 27613, 28453, 28709, 29301, 29541, 34165, 34413, 37301, - 37773, 38045, 38405, 41077, 41781, 41925, 42717, 44437, - 44525, 44613, 45933, 45941, 47077, 50077, 50893, 52117, - 5293, 55069, 55989, 58125, 59205, 6869, 14685, 15453, - 16821, 17045, 17613, 18437, 21029, 22773, 22909, 25445, - 25757, 26541, 30709, 30909, 31093, 31149, 37069, 37725, - 37925, 38949, 39637, 39701, 40765, 40861, 42965, 44813, - 45077, 45733, 47045, 50093, 52861, 52957, 54181, 56325, - 56365, 56381, 56877, 57013, 5741, 58101, 58669, 8613, - 10045, 10261, 10653, 10733, 11461, 12261, 14069, 15877, - 17757, 21165, 23885, 24701, 26429, 26645, 27925, 28765, - 29197, 30189, 31293, 39781, 39909, 40365, 41229, 41453, - 41653, 42165, 42365, 47421, 48029, 48085, 52773, 5573, - 57037, 57637, 58341, 58357, 58901, 6357, 7789, 9093, - 10125, 10709, 10765, 11957, 12469, 13437, 13509, 14773, - 15437, 15773, 17813, 18829, 19565, 20237, 23461, 23685, - 23725, 23941, 24877, 25461, 26405, 29509, 30285, 35181, - 37229, 37893, 38565, 40293, 44189, 44581, 45701, 47381, - 47589, 48557, 4941, 51069, 5165, 52797, 53149, 5341, - 56301, 56765, 58581, 59493, 59677, 6085, 6349, 8293, - 8501, 8517, 11597, 11709, 12589, 12693, 13517, 14909, - 17397, 18085, 21101, 21269, 22717, 25237, 25661, 29189, - 30101, 31397, 33933, 34213, 34661, 35533, 36493, 37309, - 40037, 4189, 42909, 44309, 44357, 44389, 4541, 45461, - 46445, 48237, 54149, 55301, 55853, 56621, 56717, 56901, - 5813, 58437, 12493, 15365, 15989, 17829, 18229, 19341, - 21013, 21357, 22925, 24885, 26053, 27581, 28221, 28485, - 30605, 30613, 30789, 35437, 36285, 37189, 3941, 41797, - 4269, 42901, 43293, 44645, 45221, 46893, 4893, 50301, - 50325, 5189, 52109, 53517, 54053, 54485, 5525, 55949, - 56973, 59069, 59421, 60733, 61253, 6421, 6701, 6709, - 7101, 8669, 15797, 19221, 19837, 20133, 20957, 21293, - 21461, 22461, 29085, 29861, 30869, 34973, 36469, 37565, - 38125, 38829, 39469, 40061, 40117, 44093, 47429, 48341, - 50597, 51757, 5541, 57629, 58405, 59621, 59693, 59701, - 61837, 7061, 10421, 11949, 15405, 20861, 25397, 25509, - 25893, 26037, 28629, 28869, 29605, 30213, 34205, 35637, - 36365, 37285, 3773, 39117, 4021, 41061, 42653, 44509, - 4461, 44829, 4725, 5125, 52269, 56469, 59085, 5917, - 60973, 8349, 17725, 18637, 19773, 20293, 21453, 22533, - 24285, 26333, 26997, 31501, 34541, 34805, 37509, 38477, - 41333, 44125, 46285, 46997, 47637, 48173, 4925, 50253, - 50381, 50917, 51205, 51325, 52165, 52229, 5253, 5269, - 53509, 56253, 56341, 5821, 58373, 60301, 61653, 61973, - 62373, 8397, 11981, 14341, 14509, 15077, 22261, 22429, - 24261, 28165, 28685, 30661, 34021, 34445, 39149, 3917, - 43013, 43317, 44053, 44101, 4533, 49541, 49981, 5277, - 54477, 56357, 57261, 57765, 58573, 59061, 60197, 61197, - 62189, 7725, 8477, 9565, 10229, 11437, 14613, 14709, - 16813, 20029, 20677, 31445, 3165, 31957, 3229, 33541, - 36645, 3805, 38973, 3965, 4029, 44293, 44557, 46245, - 48917, 4909, 51749, 53709, 55733, 56445, 5925, 6093, - 61053, 62637, 8661, 9109, 10821, 11389, 13813, 14325, - 15501, 16149, 18845, 22669, 26437, 29869, 31837, 33709, - 33973, 34173, 3677, 3877, 3981, 39885, 42117, 4421, - 44221, 44245, 44693, 46157, 47309, 5005, 51461, 52037, - 55333, 55693, 56277, 58949, 6205, 62141, 62469, 6293, - 10101, 12509, 14029, 17997, 20469, 21149, 25221, 27109, - 2773, 2877, 29405, 31493, 31645, 4077, 42005, 42077, - 42469, 42501, 44013, 48653, 49349, 4997, 50101, 55405, - 56957, 58037, 59429, 60749, 61797, 62381, 62837, 6605, - 10541, 23981, 24533, 2701, 27333, 27341, 31197, 33805, - 3621, 37381, 3749, 3829, 38533, 42613, 44381, 45901, - 48517, 51269, 57725, 59461, 60045, 62029, 13805, 14013, - 15461, 16069, 16157, 18573, 2309, 23501, 28645, 3077, - 31541, 36357, 36877, 3789, 39429, 39805, 47685, 47949, - 49413, 5485, 56757, 57549, 57805, 58317, 59549, 62213, - 62613, 62853, 62933, 8909, 12941, 16677, 20333, 21541, - 24429, 26077, 26421, 2885, 31269, 33381, 3661, 40925, - 42925, 45173, 4525, 4709, 53133, 55941, 57413, 57797, - 62125, 62237, 62733, 6773, 12317, 13197, 16533, 16933, - 18245, 2213, 2477, 29757, 33293, 35517, 40133, 40749, - 4661, 49941, 62757, 7853, 8149, 8573, 11029, 13421, - 21549, 22709, 22725, 24629, 2469, 26125, 2669, 34253, - 36709, 41013, 45597, 46637, 52285, 52333, 54685, 59013, - 60997, 61189, 61981, 62605, 62821, 7077, 7525, 8781, - 10861, 15277, 2205, 22077, 28517, 28949, 32109, 33493, - 4661, 49941, 62757, 7853, 8149, 8573, 11029, 13421, - 21549, 22709, 22725, 24629, 2469, 26125, 2669, 34253, - 36709, 41013, 45597, 46637, 52285, 52333, 54685, 59013, - 60997, 61189, 61981, 62605, 62821, 7077, 7525, 8781, - 10861, 15277, 2205, 22077, 28517, 28949, 32109, 33493, - 3685, 39197, 39869, 42621, 44997, 48565, 5221, 57381, - 61749, 62317, 63245, 63381, 23149, 2549, 28661, 31653, - 33885, 36341, 37053, 39517, 42805, 45853, 48997, 59349, - 60053, 62509, 63069, 6525, 1893, 20181, 2365, 24893, - 27397, 31357, 32277, 33357, 34437, 36677, 37661, 43469, - 43917, 50997, 53869, 5653, 13221, 16741, 17893, 2157, - 28653, 31789, 35301, 35821, 61613, 62245, 12405, 14517, - 17453, 18421, 3149, 3205, 40341, 4109, 43941, 46869, - 48837, 50621, 57405, 60509, 62877, 8157, 12933, 12957, - 16501, 19533, 3461, 36829, 52357, 58189, 58293, 63053, - 17109, 1933, 32157, 37701, 59005, 61621, 13029, 15085, - 16493, 32317, 35093, 5061, 51557, 62221, 20765, 24613, - 2629, 30861, 33197, 33749, 35365, 37933, 40317, 48045, - 56229, 61157, 63797, 7917, 17965, 1917, 1973, 20301, - 2253, 33157, 58629, 59861, 61085, 63909, 8141, 9221, - 14757, 1581, 21637, 26557, 33869, 34285, 35733, 40933, - 42517, 43501, 53653, 61885, 63805, 7141, 21653, 54973, - 31189, 60061, 60341, 63357, 16045, 2053, 26069, 33997, - 43901, 54565, 63837, 8949, 17909, 18693, 32349, 33125, - 37293, 48821, 49053, 51309, 64037, 7117, 1445, 20405, - 23085, 26269, 26293, 27349, 32381, 33141, 34525, 36461, - 37581, 43525, 4357, 43877, 5069, 55197, 63965, 9845, - 12093, 2197, 2229, 32165, 33469, 40981, 42397, 8749, - 10853, 1453, 18069, 21693, 30573, 36261, 37421, 42533 -}; - -#define NSID_MULT_TABLE_SIZE \ - ((sizeof nsid_multiplier_table)/(sizeof nsid_multiplier_table[0])) -#define NSID_RANGE_MASK (NSID_LOOKAHEAD - 1) -#define NSID_POOL_MASK 0xFFFF /* used to wrap the pool index */ -#define NSID_SHUFFLE_ONLY 1 -#define NSID_USE_POOL 2 - -static isc_uint16_t -nsid_next(dns_nsid_t *nsid) { - isc_uint16_t id, compressed_hash; - isc_uint16_t j; - - compressed_hash = ((nsid_hash_state >> 16) ^ - (nsid_hash_state)) & 0xFFFF; - - if (nsid->nsid_usepool) { - isc_uint16_t pick; - - pick = compressed_hash & NSID_RANGE_MASK; - pick = (nsid->nsid_state + pick) & NSID_POOL_MASK; - id = nsid->nsid_pool[pick]; - if (pick != 0) { - /* Swap two IDs to stir the pool */ - nsid->nsid_pool[pick] = - nsid->nsid_pool[nsid->nsid_state]; - nsid->nsid_pool[nsid->nsid_state] = id; - } - - /* increment the base pointer into the pool */ - if (nsid->nsid_state == 65535) - nsid->nsid_state = 0; - else - nsid->nsid_state++; - } else { - /* - * This is the original Algorithm B - * j = ((u_long) NSID_SHUFFLE_TABLE_SIZE * nsid_state2) >> 16; - * - * We'll perturb it with some random stuff ... - */ - j = ((isc_uint32_t) NSID_SHUFFLE_TABLE_SIZE * - (nsid->nsid_state2 ^ compressed_hash)) >> 16; - nsid->nsid_state2 = id = nsid->nsid_vtable[j]; - nsid->nsid_state = (((isc_uint32_t) nsid->nsid_a1 * nsid->nsid_state) + - nsid->nsid_c1) & 0xFFFF; - nsid->nsid_vtable[j] = nsid->nsid_state; - } - - /* Now lets obfuscate ... */ - id = (((isc_uint32_t) nsid->nsid_a2 * id) + nsid->nsid_c2) & 0xFFFF; - id = (((isc_uint32_t) nsid->nsid_a3 * id) + nsid->nsid_c3) & 0xFFFF; - - return (id); -} - -static isc_result_t -nsid_init(isc_mem_t *mctx, dns_nsid_t *nsid, isc_boolean_t usepool) { - isc_time_t now; - pid_t mypid; - isc_uint16_t a1ndx, a2ndx, a3ndx, c1ndx, c2ndx, c3ndx; - int i; - - isc_time_now(&now); - mypid = getpid(); - - /* Initialize the state */ - memset(nsid, 0, sizeof(*nsid)); - nsid_hash(&now, sizeof now); - nsid_hash(&mypid, sizeof mypid); - - /* - * Select our random number generators and initial seed. - * We could really use more random bits at this point, - * but we'll try to make a silk purse out of a sows ear ... - */ - /* generator 1 */ - a1ndx = ((isc_uint32_t) NSID_MULT_TABLE_SIZE * - (nsid_hash_state & 0xFFFF)) >> 16; - nsid->nsid_a1 = nsid_multiplier_table[a1ndx]; - c1ndx = (nsid_hash_state >> 9) & 0x7FFF; - nsid->nsid_c1 = 2 * c1ndx + 1; - - /* generator 2, distinct from 1 */ - a2ndx = ((isc_uint32_t) (NSID_MULT_TABLE_SIZE - 1) * - ((nsid_hash_state >> 10) & 0xFFFF)) >> 16; - if (a2ndx >= a1ndx) - a2ndx++; - nsid->nsid_a2 = nsid_multiplier_table[a2ndx]; - c2ndx = nsid_hash_state % 32767; - if (c2ndx >= c1ndx) - c2ndx++; - nsid->nsid_c2 = 2*c2ndx + 1; - - /* generator 3, distinct from 1 and 2 */ - a3ndx = ((isc_uint32_t) (NSID_MULT_TABLE_SIZE - 2) * - ((nsid_hash_state >> 20) & 0xFFFF)) >> 16; - if (a3ndx >= a1ndx || a3ndx >= a2ndx) - a3ndx++; - if (a3ndx >= a1ndx && a3ndx >= a2ndx) - a3ndx++; - nsid->nsid_a3 = nsid_multiplier_table[a3ndx]; - c3ndx = nsid_hash_state % 32766; - if (c3ndx >= c1ndx || c3ndx >= c2ndx) - c3ndx++; - if (c3ndx >= c1ndx && c3ndx >= c2ndx) - c3ndx++; - nsid->nsid_c3 = 2*c3ndx + 1; - - nsid->nsid_state = - ((nsid_hash_state >> 16) ^ (nsid_hash_state)) & 0xFFFF; - - nsid->nsid_usepool = usepool; - if (nsid->nsid_usepool) { - nsid->nsid_pool = isc_mem_get(mctx, 0x10000 * sizeof(isc_uint16_t)); - if (nsid->nsid_pool == NULL) - return (ISC_R_NOMEMORY); - for (i = 0; ; i++) { - nsid->nsid_pool[i] = nsid->nsid_state; - nsid->nsid_state = - (((u_long) nsid->nsid_a1 * nsid->nsid_state) + - nsid->nsid_c1) & 0xFFFF; - if (i == 0xFFFF) - break; - } - } else { - nsid->nsid_vtable = isc_mem_get(mctx, NSID_SHUFFLE_TABLE_SIZE * - (sizeof(isc_uint16_t)) ); - if (nsid->nsid_vtable == NULL) - return (ISC_R_NOMEMORY); - - for (i = 0; i < NSID_SHUFFLE_TABLE_SIZE; i++) { - nsid->nsid_vtable[i] = nsid->nsid_state; - nsid->nsid_state = - (((isc_uint32_t) nsid->nsid_a1 * nsid->nsid_state) + - nsid->nsid_c1) & 0xFFFF; - } - nsid->nsid_state2 = nsid->nsid_state; - } - return (ISC_R_SUCCESS); -} - -static void -nsid_destroy(isc_mem_t *mctx, dns_nsid_t *nsid) { - if (nsid->nsid_usepool) - isc_mem_put(mctx, nsid->nsid_pool, - 0x10000 * sizeof(isc_uint16_t)); - else - isc_mem_put(mctx, nsid->nsid_vtable, - NSID_SHUFFLE_TABLE_SIZE * (sizeof(isc_uint16_t)) ); - memset(nsid, 0, sizeof(*nsid)); -} - -void -dns_dispatch_hash(void *data, size_t len) { - nsid_hash(data, len); -} |
