contrib/bind9/bin/named/lwdclient.c

   1 /*
   2  * Copyright (C) 2004, 2005  Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (C) 2000, 2001  Internet Software Consortium.
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
  10  * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
  11  * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
  12  * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
  13  * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
  14  * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  15  * PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* $Id: lwdclient.c,v 1.17.18.2 2005/04/29 00:15:23 marka Exp $ */
  19
  20 /*! \file */
  21
  22 #include <config.h>
  23
  24 #include <isc/socket.h>
  25 #include <isc/string.h>
  26 #include <isc/task.h>
  27 #include <isc/util.h>
  28
  29 #include <dns/adb.h>
  30 #include <dns/view.h>
  31 #include <dns/log.h>
  32
  33 #include <named/types.h>
  34 #include <named/log.h>
  35 #include <named/lwresd.h>
  36 #include <named/lwdclient.h>
  37
  38 #define SHUTTINGDOWN(cm) ((cm->flags & NS_LWDCLIENTMGR_FLAGSHUTTINGDOWN) != 0)
  39
  40 static void
  41 lwdclientmgr_shutdown_callback(isc_task_t *task, isc_event_t *ev);
  42
  43 void
  44 ns_lwdclient_log(int level, const char *format, ...) {
  45         va_list args;
  46
  47         va_start(args, format);
  48         isc_log_vwrite(dns_lctx,
  49                        DNS_LOGCATEGORY_DATABASE, DNS_LOGMODULE_ADB,
  50                        ISC_LOG_DEBUG(level), format, args);
  51         va_end(args);
  52 }
  53
  54 isc_result_t
  55 ns_lwdclientmgr_create(ns_lwreslistener_t *listener, unsigned int nclients,
  56                     isc_taskmgr_t *taskmgr)
  57 {
  58         ns_lwresd_t *lwresd = listener->manager;
  59         ns_lwdclientmgr_t *cm;
  60         ns_lwdclient_t *client;
  61         unsigned int i;
  62         isc_result_t result = ISC_R_FAILURE;
  63
  64         cm = isc_mem_get(lwresd->mctx, sizeof(ns_lwdclientmgr_t));
  65         if (cm == NULL)
  66                 return (ISC_R_NOMEMORY);
  67
  68         cm->listener = NULL;
  69         ns_lwreslistener_attach(listener, &cm->listener);
  70         cm->mctx = lwresd->mctx;
  71         cm->sock = NULL;
  72         isc_socket_attach(listener->sock, &cm->sock);
  73         cm->view = lwresd->view;
  74         cm->lwctx = NULL;
  75         cm->task = NULL;
  76         cm->flags = 0;
  77         ISC_LINK_INIT(cm, link);
  78         ISC_LIST_INIT(cm->idle);
  79         ISC_LIST_INIT(cm->running);
  80
  81         if (lwres_context_create(&cm->lwctx, cm->mctx,
  82                                  ns__lwresd_memalloc, ns__lwresd_memfree,
  83                                  LWRES_CONTEXT_SERVERMODE)
  84             != ISC_R_SUCCESS)
  85                 goto errout;
  86
  87         for (i = 0; i < nclients; i++) {
  88                 client = isc_mem_get(lwresd->mctx, sizeof(ns_lwdclient_t));
  89                 if (client != NULL) {
  90                         ns_lwdclient_log(50, "created client %p, manager %p",
  91                                          client, cm);
  92                         ns_lwdclient_initialize(client, cm);
  93                 }
  94         }
  95
  96         /*
  97          * If we could create no clients, clean up and return.
  98          */
  99         if (ISC_LIST_EMPTY(cm->idle))
 100                 goto errout;
 101
 102         result = isc_task_create(taskmgr, 0, &cm->task);
 103         if (result != ISC_R_SUCCESS)
 104                 goto errout;
 105
 106         /*
 107          * This MUST be last, since there is no way to cancel an onshutdown...
 108          */
 109         result = isc_task_onshutdown(cm->task, lwdclientmgr_shutdown_callback,
 110                                      cm);
 111         if (result != ISC_R_SUCCESS)
 112                 goto errout;
 113
 114         ns_lwreslistener_linkcm(listener, cm);
 115
 116         return (ISC_R_SUCCESS);
 117
 118  errout:
 119         client = ISC_LIST_HEAD(cm->idle);
 120         while (client != NULL) {
 121                 ISC_LIST_UNLINK(cm->idle, client, link);
 122                 isc_mem_put(lwresd->mctx, client, sizeof(*client));
 123                 client = ISC_LIST_HEAD(cm->idle);
 124         }
 125
 126         if (cm->task != NULL)
 127                 isc_task_detach(&cm->task);
 128
 129         if (cm->lwctx != NULL)
 130                 lwres_context_destroy(&cm->lwctx);
 131
 132         isc_mem_put(lwresd->mctx, cm, sizeof(*cm));
 133         return (result);
 134 }
 135
 136 static void
 137 lwdclientmgr_destroy(ns_lwdclientmgr_t *cm) {
 138         ns_lwdclient_t *client;
 139         ns_lwreslistener_t *listener;
 140
 141         if (!SHUTTINGDOWN(cm))
 142                 return;
 143
 144         /*
 145          * run through the idle list and free the clients there.  Idle
 146          * clients do not have a recv running nor do they have any finds
 147          * or similar running.
 148          */
 149         client = ISC_LIST_HEAD(cm->idle);
 150         while (client != NULL) {
 151                 ns_lwdclient_log(50, "destroying client %p, manager %p",
 152                                  client, cm);
 153                 ISC_LIST_UNLINK(cm->idle, client, link);
 154                 isc_mem_put(cm->mctx, client, sizeof(*client));
 155                 client = ISC_LIST_HEAD(cm->idle);
 156         }
 157
 158         if (!ISC_LIST_EMPTY(cm->running))
 159                 return;
 160
 161         lwres_context_destroy(&cm->lwctx);
 162         cm->view = NULL;
 163         isc_socket_detach(&cm->sock);
 164         isc_task_detach(&cm->task);
 165
 166         listener = cm->listener;
 167         ns_lwreslistener_unlinkcm(listener, cm);
 168         ns_lwdclient_log(50, "destroying manager %p", cm);
 169         isc_mem_put(cm->mctx, cm, sizeof(*cm));
 170         ns_lwreslistener_detach(&listener);
 171 }
 172
 173 static void
 174 process_request(ns_lwdclient_t *client) {
 175         lwres_buffer_t b;
 176         isc_result_t result;
 177
 178         lwres_buffer_init(&b, client->buffer, client->recvlength);
 179         lwres_buffer_add(&b, client->recvlength);
 180
 181         result = lwres_lwpacket_parseheader(&b, &client->pkt);
 182         if (result != ISC_R_SUCCESS) {
 183                 ns_lwdclient_log(50, "invalid packet header received");
 184                 goto restart;
 185         }
 186
 187         ns_lwdclient_log(50, "opcode %08x", client->pkt.opcode);
 188
 189         switch (client->pkt.opcode) {
 190         case LWRES_OPCODE_GETADDRSBYNAME:
 191                 ns_lwdclient_processgabn(client, &b);
 192                 return;
 193         case LWRES_OPCODE_GETNAMEBYADDR:
 194                 ns_lwdclient_processgnba(client, &b);
 195                 return;
 196         case LWRES_OPCODE_GETRDATABYNAME:
 197                 ns_lwdclient_processgrbn(client, &b);
 198                 return;
 199         case LWRES_OPCODE_NOOP:
 200                 ns_lwdclient_processnoop(client, &b);
 201                 return;
 202         default:
 203                 ns_lwdclient_log(50, "unknown opcode %08x", client->pkt.opcode);
 204                 goto restart;
 205         }
 206
 207         /*
 208          * Drop the packet.
 209          */
 210  restart:
 211         ns_lwdclient_log(50, "restarting client %p...", client);
 212         ns_lwdclient_stateidle(client);
 213 }
 214
 215 void
 216 ns_lwdclient_recv(isc_task_t *task, isc_event_t *ev) {
 217         isc_result_t result;
 218         ns_lwdclient_t *client = ev->ev_arg;
 219         ns_lwdclientmgr_t *cm = client->clientmgr;
 220         isc_socketevent_t *dev = (isc_socketevent_t *)ev;
 221
 222         INSIST(dev->region.base == client->buffer);
 223         INSIST(NS_LWDCLIENT_ISRECV(client));
 224
 225         NS_LWDCLIENT_SETRECVDONE(client);
 226
 227         INSIST((cm->flags & NS_LWDCLIENTMGR_FLAGRECVPENDING) != 0);
 228         cm->flags &= ~NS_LWDCLIENTMGR_FLAGRECVPENDING;
 229
 230         ns_lwdclient_log(50,
 231                          "event received: task %p, length %u, result %u (%s)",
 232                          task, dev->n, dev->result,
 233                          isc_result_totext(dev->result));
 234
 235         if (dev->result != ISC_R_SUCCESS) {
 236                 isc_event_free(&ev);
 237                 dev = NULL;
 238
 239                 /*
 240                  * Go idle.
 241                  */
 242                 ns_lwdclient_stateidle(client);
 243
 244                 return;
 245         }
 246
 247         client->recvlength = dev->n;
 248         client->address = dev->address;
 249         if ((dev->attributes & ISC_SOCKEVENTATTR_PKTINFO) != 0) {
 250                 client->pktinfo = dev->pktinfo;
 251                 client->pktinfo_valid = ISC_TRUE;
 252         } else
 253                 client->pktinfo_valid = ISC_FALSE;
 254         isc_event_free(&ev);
 255         dev = NULL;
 256
 257         result = ns_lwdclient_startrecv(cm);
 258         if (result != ISC_R_SUCCESS)
 259                 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
 260                               NS_LOGMODULE_LWRESD, ISC_LOG_ERROR,
 261                               "could not start lwres "
 262                               "client handler: %s",
 263                               isc_result_totext(result));
 264
 265         process_request(client);
 266 }
 267
 268 /*
 269  * This function will start a new recv() on a socket for this client manager.
 270  */
 271 isc_result_t
 272 ns_lwdclient_startrecv(ns_lwdclientmgr_t *cm) {
 273         ns_lwdclient_t *client;
 274         isc_result_t result;
 275         isc_region_t r;
 276
 277         if (SHUTTINGDOWN(cm)) {
 278                 lwdclientmgr_destroy(cm);
 279                 return (ISC_R_SUCCESS);
 280         }
 281
 282         /*
 283          * If a recv is already running, don't bother.
 284          */
 285         if ((cm->flags & NS_LWDCLIENTMGR_FLAGRECVPENDING) != 0)
 286                 return (ISC_R_SUCCESS);
 287
 288         /*
 289          * If we have no idle slots, just return success.
 290          */
 291         client = ISC_LIST_HEAD(cm->idle);
 292         if (client == NULL)
 293                 return (ISC_R_SUCCESS);
 294         INSIST(NS_LWDCLIENT_ISIDLE(client));
 295
 296         /*
 297          * Issue the recv.  If it fails, return that it did.
 298          */
 299         r.base = client->buffer;
 300         r.length = LWRES_RECVLENGTH;
 301         result = isc_socket_recv(cm->sock, &r, 0, cm->task, ns_lwdclient_recv,
 302                                  client);
 303         if (result != ISC_R_SUCCESS)
 304                 return (result);
 305
 306         /*
 307          * Set the flag to say we've issued a recv() call.
 308          */
 309         cm->flags |= NS_LWDCLIENTMGR_FLAGRECVPENDING;
 310
 311         /*
 312          * Remove the client from the idle list, and put it on the running
 313          * list.
 314          */
 315         NS_LWDCLIENT_SETRECV(client);
 316         ISC_LIST_UNLINK(cm->idle, client, link);
 317         ISC_LIST_APPEND(cm->running, client, link);
 318
 319         return (ISC_R_SUCCESS);
 320 }
 321
 322 static void
 323 lwdclientmgr_shutdown_callback(isc_task_t *task, isc_event_t *ev) {
 324         ns_lwdclientmgr_t *cm = ev->ev_arg;
 325         ns_lwdclient_t *client;
 326
 327         REQUIRE(!SHUTTINGDOWN(cm));
 328
 329         ns_lwdclient_log(50, "got shutdown event, task %p, lwdclientmgr %p",
 330                          task, cm);
 331
 332         /*
 333          * run through the idle list and free the clients there.  Idle
 334          * clients do not have a recv running nor do they have any finds
 335          * or similar running.
 336          */
 337         client = ISC_LIST_HEAD(cm->idle);
 338         while (client != NULL) {
 339                 ns_lwdclient_log(50, "destroying client %p, manager %p",
 340                                  client, cm);
 341                 ISC_LIST_UNLINK(cm->idle, client, link);
 342                 isc_mem_put(cm->mctx, client, sizeof(*client));
 343                 client = ISC_LIST_HEAD(cm->idle);
 344         }
 345
 346         /*
 347          * Cancel any pending I/O.
 348          */
 349         isc_socket_cancel(cm->sock, task, ISC_SOCKCANCEL_ALL);
 350
 351         /*
 352          * Run through the running client list and kill off any finds
 353          * in progress.
 354          */
 355         client = ISC_LIST_HEAD(cm->running);
 356         while (client != NULL) {
 357                 if (client->find != client->v4find
 358                     && client->find != client->v6find)
 359                         dns_adb_cancelfind(client->find);
 360                 if (client->v4find != NULL)
 361                         dns_adb_cancelfind(client->v4find);
 362                 if (client->v6find != NULL)
 363                         dns_adb_cancelfind(client->v6find);
 364                 client = ISC_LIST_NEXT(client, link);
 365         }
 366
 367         cm->flags |= NS_LWDCLIENTMGR_FLAGSHUTTINGDOWN;
 368
 369         isc_event_free(&ev);
 370 }
 371
 372 /*
 373  * Do all the crap needed to move a client from the run queue to the idle
 374  * queue.
 375  */
 376 void
 377 ns_lwdclient_stateidle(ns_lwdclient_t *client) {
 378         ns_lwdclientmgr_t *cm;
 379         isc_result_t result;
 380
 381         cm = client->clientmgr;
 382
 383         INSIST(client->sendbuf == NULL);
 384         INSIST(client->sendlength == 0);
 385         INSIST(client->arg == NULL);
 386         INSIST(client->v4find == NULL);
 387         INSIST(client->v6find == NULL);
 388
 389         ISC_LIST_UNLINK(cm->running, client, link);
 390         ISC_LIST_PREPEND(cm->idle, client, link);
 391
 392         NS_LWDCLIENT_SETIDLE(client);
 393
 394         result = ns_lwdclient_startrecv(cm);
 395         if (result != ISC_R_SUCCESS)
 396                 isc_log_write(ns_g_lctx, NS_LOGCATEGORY_GENERAL,
 397                               NS_LOGMODULE_LWRESD, ISC_LOG_ERROR,
 398                               "could not start lwres "
 399                               "client handler: %s",
 400                               isc_result_totext(result));
 401 }
 402
 403 void
 404 ns_lwdclient_send(isc_task_t *task, isc_event_t *ev) {
 405         ns_lwdclient_t *client = ev->ev_arg;
 406         ns_lwdclientmgr_t *cm = client->clientmgr;
 407         isc_socketevent_t *dev = (isc_socketevent_t *)ev;
 408
 409         UNUSED(task);
 410         UNUSED(dev);
 411
 412         INSIST(NS_LWDCLIENT_ISSEND(client));
 413         INSIST(client->sendbuf == dev->region.base);
 414
 415         ns_lwdclient_log(50, "task %p for client %p got send-done event",
 416                          task, client);
 417
 418         if (client->sendbuf != client->buffer)
 419                 lwres_context_freemem(cm->lwctx, client->sendbuf,
 420                                       client->sendlength);
 421         client->sendbuf = NULL;
 422         client->sendlength = 0;
 423
 424         ns_lwdclient_stateidle(client);
 425
 426         isc_event_free(&ev);
 427 }
 428
 429 isc_result_t
 430 ns_lwdclient_sendreply(ns_lwdclient_t *client, isc_region_t *r) {
 431         struct in6_pktinfo *pktinfo;
 432         ns_lwdclientmgr_t *cm = client->clientmgr;
 433
 434         if (client->pktinfo_valid)
 435                 pktinfo = &client->pktinfo;
 436         else
 437                 pktinfo = NULL;
 438         return (isc_socket_sendto(cm->sock, r, cm->task, ns_lwdclient_send,
 439                                   client, &client->address, pktinfo));
 440 }
 441
 442 void
 443 ns_lwdclient_initialize(ns_lwdclient_t *client, ns_lwdclientmgr_t *cmgr) {
 444         client->clientmgr = cmgr;
 445         ISC_LINK_INIT(client, link);
 446         NS_LWDCLIENT_SETIDLE(client);
 447         client->arg = NULL;
 448
 449         client->recvlength = 0;
 450
 451         client->sendbuf = NULL;
 452         client->sendlength = 0;
 453
 454         client->find = NULL;
 455         client->v4find = NULL;
 456         client->v6find = NULL;
 457         client->find_wanted = 0;
 458
 459         client->options = 0;
 460         client->byaddr = NULL;
 461
 462         client->lookup = NULL;
 463
 464         client->pktinfo_valid = ISC_FALSE;
 465
 466         ISC_LIST_APPEND(cmgr->idle, client, link);
 467 }