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-rw-r--r--lib/dns/dispatch.c190
1 files changed, 178 insertions, 12 deletions
diff --git a/lib/dns/dispatch.c b/lib/dns/dispatch.c
index 794cdb5..9b4e968 100644
--- a/lib/dns/dispatch.c
+++ b/lib/dns/dispatch.c
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2004-2008 Internet Systems Consortium, Inc. ("ISC")
+ * Copyright (C) 2004-2009 Internet Systems Consortium, Inc. ("ISC")
* Copyright (C) 1999-2003 Internet Software Consortium.
*
* Permission to use, copy, modify, and/or distribute this software for any
@@ -15,7 +15,7 @@
* PERFORMANCE OF THIS SOFTWARE.
*/
-/* $Id: dispatch.c,v 1.116.18.37 2008/09/04 00:24:41 jinmei Exp $ */
+/* $Id: dispatch.c,v 1.155.12.7 2009/04/28 21:39:45 jinmei Exp $ */
/*! \file */
@@ -32,6 +32,7 @@
#include <isc/portset.h>
#include <isc/print.h>
#include <isc/random.h>
+#include <isc/stats.h>
#include <isc/string.h>
#include <isc/task.h>
#include <isc/time.h>
@@ -43,14 +44,18 @@
#include <dns/log.h>
#include <dns/message.h>
#include <dns/portlist.h>
+#include <dns/stats.h>
#include <dns/tcpmsg.h>
#include <dns/types.h>
typedef ISC_LIST(dns_dispentry_t) dns_displist_t;
-typedef struct dispsocket dispsocket_t;
+typedef struct dispsocket dispsocket_t;
typedef ISC_LIST(dispsocket_t) dispsocketlist_t;
+typedef struct dispportentry dispportentry_t;
+typedef ISC_LIST(dispportentry_t) dispportlist_t;
+
/* ARC4 Random generator state */
typedef struct arc4ctx {
isc_uint8_t i;
@@ -76,6 +81,7 @@ struct dns_dispatchmgr {
isc_mem_t *mctx;
dns_acl_t *blackhole;
dns_portlist_t *portlist;
+ isc_stats_t *stats;
isc_entropy_t *entropy; /*%< entropy source */
/* Locked by "lock". */
@@ -170,7 +176,8 @@ struct dispsocket {
isc_socket_t *socket;
dns_dispatch_t *disp;
isc_sockaddr_t host;
- in_port_t localport;
+ in_port_t localport; /* XXX: should be removed later */
+ dispportentry_t *portentry;
dns_dispentry_t *resp;
isc_task_t *task;
ISC_LINK(dispsocket_t) link;
@@ -178,6 +185,21 @@ struct dispsocket {
ISC_LINK(dispsocket_t) blink;
};
+/*%
+ * A port table entry. We remember every port we first open in a table with a
+ * reference counter so that we can 'reuse' the same port (with different
+ * destination addresses) using the SO_REUSEADDR socket option.
+ */
+struct dispportentry {
+ in_port_t port;
+ unsigned int refs;
+ ISC_LINK(struct dispportentry) link;
+};
+
+#ifndef DNS_DISPATCH_PORTTABLESIZE
+#define DNS_DISPATCH_PORTTABLESIZE 1024
+#endif
+
#define INVALID_BUCKET (0xffffdead)
/*%
@@ -227,6 +249,8 @@ struct dns_dispatch {
dns_tcpmsg_t tcpmsg; /*%< for tcp streams */
dns_qid_t *qid;
arc4ctx_t arc4ctx; /*%< for QID/UDP port num */
+ dispportlist_t *port_table; /*%< hold ports 'owned' by us */
+ isc_mempool_t *portpool; /*%< port table entries */
};
#define QID_MAGIC ISC_MAGIC('Q', 'i', 'd', ' ')
@@ -330,6 +354,12 @@ mgr_log(dns_dispatchmgr_t *mgr, int level, const char *fmt, ...) {
level, "dispatchmgr %p: %s", mgr, msgbuf);
}
+static inline void
+inc_stats(dns_dispatchmgr_t *mgr, isc_statscounter_t counter) {
+ if (mgr->stats != NULL)
+ isc_stats_increment(mgr->stats, counter);
+}
+
static void
dispatch_log(dns_dispatch_t *disp, int level, const char *fmt, ...)
ISC_FORMAT_PRINTF(3, 4);
@@ -677,6 +707,64 @@ destroy_disp(isc_task_t *task, isc_event_t *event) {
}
/*%
+ * Manipulate port table per dispatch: find an entry for a given port number,
+ * create a new entry, and decrement a given entry with possible clean-up.
+ */
+static dispportentry_t *
+port_search(dns_dispatch_t *disp, in_port_t port) {
+ dispportentry_t *portentry;
+
+ REQUIRE(disp->port_table != NULL);
+
+ portentry = ISC_LIST_HEAD(disp->port_table[port %
+ DNS_DISPATCH_PORTTABLESIZE]);
+ while (portentry != NULL) {
+ if (portentry->port == port)
+ return (portentry);
+ portentry = ISC_LIST_NEXT(portentry, link);
+ }
+
+ return (NULL);
+}
+
+static dispportentry_t *
+new_portentry(dns_dispatch_t *disp, in_port_t port) {
+ dispportentry_t *portentry;
+
+ REQUIRE(disp->port_table != NULL);
+
+ portentry = isc_mempool_get(disp->portpool);
+ if (portentry == NULL)
+ return (portentry);
+
+ portentry->port = port;
+ portentry->refs = 0;
+ ISC_LINK_INIT(portentry, link);
+ ISC_LIST_APPEND(disp->port_table[port % DNS_DISPATCH_PORTTABLESIZE],
+ portentry, link);
+
+ return (portentry);
+}
+
+static void
+deref_portentry(dns_dispatch_t *disp, dispportentry_t **portentryp) {
+ dispportentry_t *portentry = *portentryp;
+
+ REQUIRE(disp->port_table != NULL);
+ REQUIRE(portentry != NULL && portentry->refs > 0);
+
+ portentry->refs--;
+ if (portentry->refs == 0) {
+ ISC_LIST_UNLINK(disp->port_table[portentry->port %
+ DNS_DISPATCH_PORTTABLESIZE],
+ portentry, link);
+ isc_mempool_put(disp->portpool, portentry);
+ }
+
+ *portentryp = NULL;
+}
+
+/*%
* Find a dispsocket for socket address 'dest', and port number 'port'.
* Return NULL if no such entry exists.
*/
@@ -692,7 +780,7 @@ socket_search(dns_qid_t *qid, isc_sockaddr_t *dest, in_port_t port,
while (dispsock != NULL) {
if (isc_sockaddr_equal(dest, &dispsock->host) &&
- dispsock->localport == port)
+ dispsock->portentry->port == port)
return (dispsock);
dispsock = ISC_LIST_NEXT(dispsock, blink);
}
@@ -720,6 +808,8 @@ get_dispsocket(dns_dispatch_t *disp, isc_sockaddr_t *dest,
dispsocket_t *dispsock;
unsigned int nports;
in_port_t *ports;
+ unsigned int bindoptions;
+ dispportentry_t *portentry = NULL;
if (isc_sockaddr_pf(&disp->local) == AF_INET) {
nports = disp->mgr->nv4ports;
@@ -745,6 +835,7 @@ get_dispsocket(dns_dispatch_t *disp, isc_sockaddr_t *dest,
dispsock->socket = NULL;
dispsock->disp = disp;
dispsock->resp = NULL;
+ dispsock->portentry = NULL;
isc_random_get(&r);
dispsock->task = NULL;
isc_task_attach(disp->task[r % disp->ntasks], &dispsock->task);
@@ -767,16 +858,29 @@ get_dispsocket(dns_dispatch_t *disp, isc_sockaddr_t *dest,
bucket = dns_hash(qid, dest, 0, port);
if (socket_search(qid, dest, port, bucket) != NULL)
continue;
-
- result = open_socket(sockmgr, &localaddr, 0, &sock);
- if (result == ISC_R_SUCCESS || result != ISC_R_ADDRINUSE)
+ bindoptions = 0;
+ portentry = port_search(disp, port);
+ if (portentry != NULL)
+ bindoptions |= ISC_SOCKET_REUSEADDRESS;
+ result = open_socket(sockmgr, &localaddr, bindoptions, &sock);
+ if (result == ISC_R_SUCCESS) {
+ if (portentry == NULL) {
+ portentry = new_portentry(disp, port);
+ if (portentry == NULL) {
+ result = ISC_R_NOMEMORY;
+ break;
+ }
+ }
+ portentry->refs++;
+ break;
+ } else if (result != ISC_R_ADDRINUSE)
break;
}
if (result == ISC_R_SUCCESS) {
dispsock->socket = sock;
dispsock->host = *dest;
- dispsock->localport = port;
+ dispsock->portentry = portentry;
dispsock->bucket = bucket;
ISC_LIST_APPEND(qid->sock_table[bucket], dispsock, blink);
*dispsockp = dispsock;
@@ -813,6 +917,8 @@ destroy_dispsocket(dns_dispatch_t *disp, dispsocket_t **dispsockp) {
disp->nsockets--;
dispsock->magic = 0;
+ if (dispsock->portentry != NULL)
+ deref_portentry(disp, &dispsock->portentry);
if (dispsock->socket != NULL)
isc_socket_detach(&dispsock->socket);
if (ISC_LINK_LINKED(dispsock, blink)) {
@@ -847,6 +953,9 @@ deactivate_dispsocket(dns_dispatch_t *disp, dispsocket_t *dispsock) {
dispsock->resp->dispsocket = NULL;
}
+ INSIST(dispsock->portentry != NULL);
+ deref_portentry(disp, &dispsock->portentry);
+
if (disp->nsockets > DNS_DISPATCH_POOLSOCKS)
destroy_dispsocket(disp, &dispsock);
else {
@@ -1161,6 +1270,7 @@ udp_recv(isc_event_t *ev_in, dns_dispatch_t *disp, dispsocket_t *dispsock) {
bucket, (resp == NULL ? "not found" : "found"));
if (resp == NULL) {
+ inc_stats(mgr, dns_resstatscounter_mismatch);
free_buffer(disp, ev->region.base, ev->region.length);
goto unlock;
}
@@ -1168,6 +1278,7 @@ udp_recv(isc_event_t *ev_in, dns_dispatch_t *disp, dispsocket_t *dispsock) {
&resp->host)) {
dispatch_log(disp, LVL(90),
"response to an exclusive socket doesn't match");
+ inc_stats(mgr, dns_resstatscounter_mismatch);
free_buffer(disp, ev->region.base, ev->region.length);
goto unlock;
}
@@ -1603,6 +1714,9 @@ destroy_mgr(dns_dispatchmgr_t **mgrp) {
if (mgr->blackhole != NULL)
dns_acl_detach(&mgr->blackhole);
+ if (mgr->stats != NULL)
+ isc_stats_detach(&mgr->stats);
+
if (mgr->v4ports != NULL) {
isc_mem_put(mctx, mgr->v4ports,
mgr->nv4ports * sizeof(in_port_t));
@@ -1628,6 +1742,7 @@ open_socket(isc_socketmgr_t *mgr, isc_sockaddr_t *local,
isc_sockettype_udp, &sock);
if (result != ISC_R_SUCCESS)
return (result);
+ isc_socket_setname(sock, "dispatcher", NULL);
} else {
result = isc_socket_open(sock);
if (result != ISC_R_SUCCESS)
@@ -1692,6 +1807,7 @@ dns_dispatchmgr_create(isc_mem_t *mctx, isc_entropy_t *entropy,
isc_mem_attach(mctx, &mgr->mctx);
mgr->blackhole = NULL;
+ mgr->stats = NULL;
result = isc_mutex_init(&mgr->lock);
if (result != ISC_R_SUCCESS)
@@ -2001,6 +2117,15 @@ dns_dispatchmgr_destroy(dns_dispatchmgr_t **mgrp) {
destroy_mgr(&mgr);
}
+void
+dns_dispatchmgr_setstats(dns_dispatchmgr_t *mgr, isc_stats_t *stats) {
+ REQUIRE(VALID_DISPATCHMGR(mgr));
+ REQUIRE(ISC_LIST_EMPTY(mgr->list));
+ REQUIRE(mgr->stats == NULL);
+
+ isc_stats_attach(stats, &mgr->stats);
+}
+
static int
port_cmp(const void *key, const void *ent) {
in_port_t p1 = *(const in_port_t *)key;
@@ -2269,6 +2394,8 @@ dispatch_allocate(dns_dispatchmgr_t *mgr, unsigned int maxrequests,
ISC_LIST_INIT(disp->inactivesockets);
disp->nsockets = 0;
dispatch_arc4init(&disp->arc4ctx, mgr->entropy, NULL);
+ disp->port_table = NULL;
+ disp->portpool = NULL;
result = isc_mutex_init(&disp->lock);
if (result != ISC_R_SUCCESS)
@@ -2298,13 +2425,14 @@ dispatch_allocate(dns_dispatchmgr_t *mgr, unsigned int maxrequests,
/*
- * MUST be unlocked, and not used by anthing.
+ * MUST be unlocked, and not used by anything.
*/
static void
dispatch_free(dns_dispatch_t **dispp)
{
dns_dispatch_t *disp;
dns_dispatchmgr_t *mgr;
+ int i;
REQUIRE(VALID_DISPATCH(*dispp));
disp = *dispp;
@@ -2329,6 +2457,18 @@ dispatch_free(dns_dispatch_t **dispp)
if (disp->qid != NULL)
qid_destroy(mgr->mctx, &disp->qid);
+
+ if (disp->port_table != NULL) {
+ for (i = 0; i < DNS_DISPATCH_PORTTABLESIZE; i++)
+ INSIST(ISC_LIST_EMPTY(disp->port_table[i]));
+ isc_mem_put(mgr->mctx, disp->port_table,
+ sizeof(disp->port_table[0]) *
+ DNS_DISPATCH_PORTTABLESIZE);
+ }
+
+ if (disp->portpool != NULL)
+ isc_mempool_destroy(&disp->portpool);
+
disp->mgr = NULL;
DESTROYLOCK(&disp->lock);
disp->magic = 0;
@@ -2462,9 +2602,8 @@ dns_dispatch_getudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr,
}
/*
- * First, see if we have a dispatcher that matches.
+ * 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++;
@@ -2569,6 +2708,15 @@ get_udpsocket(dns_dispatchmgr_t *mgr, dns_dispatch_t *disp,
* If this fails 1024 times, we then ask the kernel for
* choosing one.
*/
+ } else {
+ /* Allow to reuse address for non-random ports. */
+ result = open_socket(sockmgr, localaddr,
+ ISC_SOCKET_REUSEADDRESS, &sock);
+
+ if (result == ISC_R_SUCCESS)
+ *sockp = sock;
+
+ return (result);
}
memset(held, 0, sizeof(held));
@@ -2650,6 +2798,21 @@ dispatch_createudp(dns_dispatchmgr_t *mgr, isc_socketmgr_t *sockmgr,
if (result != ISC_R_SUCCESS)
goto deallocate_dispatch;
}
+
+ disp->port_table = isc_mem_get(mgr->mctx,
+ sizeof(disp->port_table[0]) *
+ DNS_DISPATCH_PORTTABLESIZE);
+ if (disp->port_table == NULL)
+ goto deallocate_dispatch;
+ for (i = 0; i < DNS_DISPATCH_PORTTABLESIZE; i++)
+ ISC_LIST_INIT(disp->port_table[i]);
+
+ result = isc_mempool_create(mgr->mctx, sizeof(dispportentry_t),
+ &disp->portpool);
+ if (result != ISC_R_SUCCESS)
+ goto deallocate_dispatch;
+ isc_mempool_setname(disp->portpool, "disp_portpool");
+ isc_mempool_setfreemax(disp->portpool, 128);
}
disp->socktype = isc_sockettype_udp;
disp->socket = sock;
@@ -2829,6 +2992,8 @@ dns_dispatch_addresponse2(dns_dispatch_t *disp, isc_sockaddr_t *dest,
oldestresp->item_out = ISC_TRUE;
isc_task_send(oldestresp->task,
ISC_EVENT_PTR(&rev));
+ inc_stats(disp->mgr,
+ dns_resstatscounter_dispabort);
}
}
@@ -2852,6 +3017,7 @@ dns_dispatch_addresponse2(dns_dispatch_t *disp, isc_sockaddr_t *dest,
if (result != ISC_R_SUCCESS) {
UNLOCK(&qid->lock);
UNLOCK(&disp->lock);
+ inc_stats(disp->mgr, dns_resstatscounter_dispsockfail);
return (result);
}
} else {
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