lnet/lnet/acceptor.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, 2017, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  * Lustre is a trademark of Sun Microsystems, Inc.
  31  */
  32
  33 #define DEBUG_SUBSYSTEM S_LNET
  34
  35 #include <linux/completion.h>
  36 #include <net/sock.h>
  37 #include <lnet/lib-lnet.h>
  38
  39 static int   accept_port    = 988;
  40 static int   accept_backlog = 127;
  41 static int   accept_timeout = 5;
  42
  43 static struct {
  44         int                     pta_shutdown;
  45         struct socket           *pta_sock;
  46         struct completion       pta_signal;
  47         struct net              *pta_ns;
  48         wait_queue_head_t       pta_waitq;
  49         atomic_t                pta_ready;
  50 #ifdef HAVE_SK_DATA_READY_ONE_ARG
  51         void                    (*pta_odata)(struct sock *);
  52 #else
  53         void                    (*pta_odata)(struct sock *, int);
  54 #endif
  55 } lnet_acceptor_state = {
  56         .pta_shutdown = 1
  57 };
  58
  59 int
  60 lnet_acceptor_port(void)
  61 {
  62         return accept_port;
  63 }
  64
  65 static inline int
  66 lnet_accept_magic(__u32 magic, __u32 constant)
  67 {
  68         return (magic == constant ||
  69                 magic == __swab32(constant));
  70 }
  71
  72 EXPORT_SYMBOL(lnet_acceptor_port);
  73
  74 static char *accept_type = "secure";
  75
  76 module_param_named(accept, accept_type, charp, 0444);
  77 MODULE_PARM_DESC(accept, "Accept connections (secure|all|none)");
  78 module_param(accept_port, int, 0444);
  79 MODULE_PARM_DESC(accept_port, "Acceptor's port (same on all nodes)");
  80 module_param(accept_backlog, int, 0444);
  81 MODULE_PARM_DESC(accept_backlog, "Acceptor's listen backlog");
  82 module_param(accept_timeout, int, 0644);
  83 MODULE_PARM_DESC(accept_timeout, "Acceptor's timeout (seconds)");
  84
  85 int
  86 lnet_acceptor_timeout(void)
  87 {
  88         return accept_timeout;
  89 }
  90 EXPORT_SYMBOL(lnet_acceptor_timeout);
  91
  92 void
  93 lnet_connect_console_error (int rc, lnet_nid_t peer_nid,
  94                            __u32 peer_ip, int peer_port)
  95 {
  96         switch (rc) {
  97         /* "normal" errors */
  98         case -ECONNREFUSED:
  99                 CNETERR("Connection to %s at host %pI4h on port %d was "
 100                         "refused: check that Lustre is running on that node.\n",
 101                         libcfs_nid2str(peer_nid), &peer_ip, peer_port);
 102                 break;
 103         case -EHOSTUNREACH:
 104         case -ENETUNREACH:
 105                 CNETERR("Connection to %s at host %pI4h "
 106                         "was unreachable: the network or that node may "
 107                         "be down, or Lustre may be misconfigured.\n",
 108                         libcfs_nid2str(peer_nid), &peer_ip);
 109                 break;
 110         case -ETIMEDOUT:
 111                 CNETERR("Connection to %s at host %pI4h on "
 112                         "port %d took too long: that node may be hung "
 113                         "or experiencing high load.\n",
 114                         libcfs_nid2str(peer_nid), &peer_ip, peer_port);
 115                 break;
 116         case -ECONNRESET:
 117                 LCONSOLE_ERROR_MSG(0x11b, "Connection to %s at host %pI4h"
 118                                    " on port %d was reset: "
 119                                    "is it running a compatible version of "
 120                                    "Lustre and is %s one of its NIDs?\n",
 121                                    libcfs_nid2str(peer_nid), &peer_ip,
 122                                    peer_port, libcfs_nid2str(peer_nid));
 123                 break;
 124         case -EPROTO:
 125                 LCONSOLE_ERROR_MSG(0x11c, "Protocol error connecting to %s at "
 126                                    "host %pI4h on port %d: is it running "
 127                                    "a compatible version of Lustre?\n",
 128                                    libcfs_nid2str(peer_nid), &peer_ip,
 129                                    peer_port);
 130                 break;
 131         case -EADDRINUSE:
 132                 LCONSOLE_ERROR_MSG(0x11d, "No privileged ports available to "
 133                                    "connect to %s at host %pI4h on port "
 134                                    "%d\n", libcfs_nid2str(peer_nid),
 135                                    &peer_ip, peer_port);
 136                 break;
 137         default:
 138                 LCONSOLE_ERROR_MSG(0x11e, "Unexpected error %d connecting to %s"
 139                                    " at host %pI4h on port %d\n", rc,
 140                                    libcfs_nid2str(peer_nid),
 141                                    &peer_ip, peer_port);
 142                 break;
 143         }
 144 }
 145 EXPORT_SYMBOL(lnet_connect_console_error);
 146
 147 struct socket *
 148 lnet_connect(lnet_nid_t peer_nid, int interface, __u32 peer_ip,
 149              int peer_port, struct net *ns)
 150 {
 151         struct lnet_acceptor_connreq cr;
 152         struct socket           *sock;
 153         int                     rc;
 154         int                     port;
 155
 156         BUILD_BUG_ON(sizeof(cr) > 16); /* not too big to be on the stack */
 157
 158         for (port = LNET_ACCEPTOR_MAX_RESERVED_PORT;
 159              port >= LNET_ACCEPTOR_MIN_RESERVED_PORT;
 160              --port) {
 161                 /* Iterate through reserved ports. */
 162                 struct sockaddr_in paddr = {.sin_family = AF_INET};
 163
 164                 paddr.sin_addr.s_addr = htonl(peer_ip);
 165                 paddr.sin_port = htons(peer_port);
 166                 sock = lnet_sock_connect(interface, port,
 167                                          (struct sockaddr *)&paddr, ns);
 168                 if (IS_ERR(sock)) {
 169                         rc = PTR_ERR(sock);
 170                         if (rc == -EADDRINUSE || rc == -EADDRNOTAVAIL)
 171                                 continue;
 172                         goto failed;
 173                 }
 174
 175                 BUILD_BUG_ON(LNET_PROTO_ACCEPTOR_VERSION != 1);
 176
 177                 cr.acr_magic   = LNET_PROTO_ACCEPTOR_MAGIC;
 178                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 179                 cr.acr_nid     = peer_nid;
 180
 181                 if (the_lnet.ln_testprotocompat) {
 182                         /* single-shot proto check */
 183                         if (test_and_clear_bit(2, &the_lnet.ln_testprotocompat))
 184                                 cr.acr_version++;
 185                         if (test_and_clear_bit(3, &the_lnet.ln_testprotocompat))
 186                                 cr.acr_magic = LNET_PROTO_MAGIC;
 187                 }
 188
 189                 rc = lnet_sock_write(sock, &cr, sizeof(cr),
 190                                        accept_timeout);
 191                 if (rc != 0)
 192                         goto failed_sock;
 193
 194                 return sock;
 195         }
 196
 197         rc = -EADDRINUSE;
 198         goto failed;
 199
 200 failed_sock:
 201         sock_release(sock);
 202 failed:
 203         lnet_connect_console_error(rc, peer_nid, peer_ip, peer_port);
 204         return ERR_PTR(rc);
 205 }
 206 EXPORT_SYMBOL(lnet_connect);
 207
 208 static int
 209 lnet_accept(struct socket *sock, __u32 magic)
 210 {
 211         struct lnet_acceptor_connreq cr;
 212         __u32                   peer_ip;
 213         int                     peer_port;
 214         int                     rc;
 215         int                     flip;
 216         struct lnet_ni *ni;
 217         char                   *str;
 218
 219         LASSERT(sizeof(cr) <= 16);              /* not too big for the stack */
 220
 221         rc = lnet_sock_getaddr(sock, true, &peer_ip, &peer_port);
 222         LASSERT(rc == 0);                       /* we succeeded before */
 223
 224         if (!lnet_accept_magic(magic, LNET_PROTO_ACCEPTOR_MAGIC)) {
 225
 226                 if (lnet_accept_magic(magic, LNET_PROTO_MAGIC)) {
 227                         /* future version compatibility!
 228                          * When LNET unifies protocols over all LNDs, the first
 229                          * thing sent will be a version query.  I send back
 230                          * LNET_PROTO_ACCEPTOR_MAGIC to tell her I'm "old" */
 231
 232                         memset(&cr, 0, sizeof(cr));
 233                         cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 234                         cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 235                         rc = lnet_sock_write(sock, &cr, sizeof(cr),
 236                                                accept_timeout);
 237
 238                         if (rc != 0)
 239                                 CERROR("Error sending magic+version in response to LNET magic from %pI4h: %d\n",
 240                                        &peer_ip, rc);
 241                         return -EPROTO;
 242                 }
 243
 244                 if (lnet_accept_magic(magic, LNET_PROTO_TCP_MAGIC))
 245                         str = "'old' socknal/tcpnal";
 246                 else
 247                         str = "unrecognised";
 248
 249                 LCONSOLE_ERROR_MSG(0x11f, "Refusing connection from %pI4h"
 250                                    " magic %08x: %s acceptor protocol\n",
 251                                    &peer_ip, magic, str);
 252                 return -EPROTO;
 253         }
 254
 255         flip = (magic != LNET_PROTO_ACCEPTOR_MAGIC);
 256
 257         rc = lnet_sock_read(sock, &cr.acr_version,
 258                               sizeof(cr.acr_version),
 259                               accept_timeout);
 260         if (rc != 0) {
 261                 CERROR("Error %d reading connection request version from "
 262                        "%pI4h\n", rc, &peer_ip);
 263                 return -EIO;
 264         }
 265
 266         if (flip)
 267                 __swab32s(&cr.acr_version);
 268
 269         if (cr.acr_version != LNET_PROTO_ACCEPTOR_VERSION) {
 270                 /* future version compatibility!
 271                  * An acceptor-specific protocol rev will first send a version
 272                  * query.  I send back my current version to tell her I'm
 273                  * "old". */
 274                 int peer_version = cr.acr_version;
 275
 276                 memset(&cr, 0, sizeof(cr));
 277                 cr.acr_magic = LNET_PROTO_ACCEPTOR_MAGIC;
 278                 cr.acr_version = LNET_PROTO_ACCEPTOR_VERSION;
 279
 280                 rc = lnet_sock_write(sock, &cr, sizeof(cr),
 281                                        accept_timeout);
 282
 283                 if (rc != 0)
 284                         CERROR("Error sending magic+version in response to version %d from %pI4h: %d\n",
 285                                peer_version, &peer_ip, rc);
 286                 return -EPROTO;
 287         }
 288
 289         rc = lnet_sock_read(sock, &cr.acr_nid,
 290                               sizeof(cr) -
 291                               offsetof(struct lnet_acceptor_connreq, acr_nid),
 292                               accept_timeout);
 293         if (rc != 0) {
 294                 CERROR("Error %d reading connection request from "
 295                        "%pI4h\n", rc, &peer_ip);
 296                 return -EIO;
 297         }
 298
 299         if (flip)
 300                 __swab64s(&cr.acr_nid);
 301
 302         ni = lnet_nid2ni_addref(cr.acr_nid);
 303         if (ni == NULL ||               /* no matching net */
 304             ni->ni_nid != cr.acr_nid) { /* right NET, wrong NID! */
 305                 if (ni != NULL)
 306                         lnet_ni_decref(ni);
 307                 LCONSOLE_ERROR_MSG(0x120, "Refusing connection from %pI4h "
 308                                    "for %s: No matching NI\n",
 309                                    &peer_ip, libcfs_nid2str(cr.acr_nid));
 310                 return -EPERM;
 311         }
 312
 313         if (ni->ni_net->net_lnd->lnd_accept == NULL) {
 314                 /* This catches a request for the loopback LND */
 315                 lnet_ni_decref(ni);
 316                 LCONSOLE_ERROR_MSG(0x121, "Refusing connection from %pI4h "
 317                                   "for %s: NI doesn not accept IP connections\n",
 318                                   &peer_ip, libcfs_nid2str(cr.acr_nid));
 319                 return -EPERM;
 320         }
 321
 322         CDEBUG(D_NET, "Accept %s from %pI4h\n",
 323                libcfs_nid2str(cr.acr_nid), &peer_ip);
 324
 325         rc = ni->ni_net->net_lnd->lnd_accept(ni, sock);
 326
 327         lnet_ni_decref(ni);
 328         return rc;
 329 }
 330
 331 #ifdef HAVE_SK_DATA_READY_ONE_ARG
 332 static void lnet_acceptor_ready(struct sock *sk)
 333 #else
 334 static void lnet_acceptor_ready(struct sock *sk, int len)
 335 #endif
 336 {
 337         /* Ensure pta_odata has actually been set before calling it */
 338         rmb();
 339 #ifdef HAVE_SK_DATA_READY_ONE_ARG
 340         lnet_acceptor_state.pta_odata(sk);
 341 #else
 342         lnet_acceptor_state.pta_odata(sk, 0);
 343 #endif
 344
 345         atomic_set(&lnet_acceptor_state.pta_ready, 1);
 346         wake_up(&lnet_acceptor_state.pta_waitq);
 347 }
 348
 349 static int
 350 lnet_acceptor(void *arg)
 351 {
 352         struct socket  *newsock;
 353         int            rc;
 354         __u32          magic;
 355         __u32          peer_ip;
 356         int            peer_port;
 357         int            secure = (int)((uintptr_t)arg);
 358
 359         LASSERT(lnet_acceptor_state.pta_sock == NULL);
 360
 361         lnet_acceptor_state.pta_sock =
 362                 lnet_sock_listen(accept_port, accept_backlog,
 363                                  lnet_acceptor_state.pta_ns);
 364         if (IS_ERR(lnet_acceptor_state.pta_sock)) {
 365                 rc = PTR_ERR(lnet_acceptor_state.pta_sock);
 366                 if (rc == -EADDRINUSE)
 367                         LCONSOLE_ERROR_MSG(0x122, "Can't start acceptor on port"
 368                                            " %d: port already in use\n",
 369                                            accept_port);
 370                 else
 371                         LCONSOLE_ERROR_MSG(0x123, "Can't start acceptor on port "
 372                                            "%d: unexpected error %d\n",
 373                                            accept_port, rc);
 374
 375                 lnet_acceptor_state.pta_sock = NULL;
 376         } else {
 377                 rc = 0;
 378                 LCONSOLE(0, "Accept %s, port %d\n", accept_type, accept_port);
 379                 init_waitqueue_head(&lnet_acceptor_state.pta_waitq);
 380                 lnet_acceptor_state.pta_odata =
 381                         lnet_acceptor_state.pta_sock->sk->sk_data_ready;
 382                 /* ensure pta_odata gets set before there is any chance of
 383                  * lnet_accept_ready() trying to read it.
 384                  */
 385                 wmb();
 386                 lnet_acceptor_state.pta_sock->sk->sk_data_ready =
 387                         lnet_acceptor_ready;
 388                 atomic_set(&lnet_acceptor_state.pta_ready, 1);
 389         }
 390
 391         /* set init status and unblock parent */
 392         lnet_acceptor_state.pta_shutdown = rc;
 393         complete(&lnet_acceptor_state.pta_signal);
 394
 395         if (rc != 0)
 396                 return rc;
 397
 398         while (!lnet_acceptor_state.pta_shutdown) {
 399
 400                 wait_event_idle(lnet_acceptor_state.pta_waitq,
 401                                 lnet_acceptor_state.pta_shutdown ||
 402                                 atomic_read(&lnet_acceptor_state.pta_ready));
 403                 if (!atomic_read(&lnet_acceptor_state.pta_ready))
 404                         continue;
 405                 atomic_set(&lnet_acceptor_state.pta_ready, 0);
 406                 rc = kernel_accept(lnet_acceptor_state.pta_sock, &newsock,
 407                                    SOCK_NONBLOCK);
 408                 if (rc != 0) {
 409                         if (rc != -EAGAIN) {
 410                                 CWARN("Accept error %d: pausing...\n", rc);
 411                                 schedule_timeout_uninterruptible(
 412                                         cfs_time_seconds(1));
 413                         }
 414                         continue;
 415                 }
 416
 417                 /* make sure we call lnet_sock_accept() again, until it fails */
 418                 atomic_set(&lnet_acceptor_state.pta_ready, 1);
 419
 420                 rc = lnet_sock_getaddr(newsock, true, &peer_ip, &peer_port);
 421                 if (rc != 0) {
 422                         CERROR("Can't determine new connection's address\n");
 423                         goto failed;
 424                 }
 425
 426                 if (secure && peer_port > LNET_ACCEPTOR_MAX_RESERVED_PORT) {
 427                         CERROR("Refusing connection from %pI4h: "
 428                                "insecure port %d\n", &peer_ip, peer_port);
 429                         goto failed;
 430                 }
 431
 432                 rc = lnet_sock_read(newsock, &magic, sizeof(magic),
 433                                       accept_timeout);
 434                 if (rc != 0) {
 435                         CERROR("Error %d reading connection request from "
 436                                "%pI4h\n", rc, &peer_ip);
 437                         goto failed;
 438                 }
 439
 440                 rc = lnet_accept(newsock, magic);
 441                 if (rc != 0)
 442                         goto failed;
 443
 444                 continue;
 445
 446 failed:
 447                 sock_release(newsock);
 448         }
 449
 450         lnet_acceptor_state.pta_sock->sk->sk_data_ready =
 451                 lnet_acceptor_state.pta_odata;
 452         sock_release(lnet_acceptor_state.pta_sock);
 453         lnet_acceptor_state.pta_sock = NULL;
 454
 455         CDEBUG(D_NET, "Acceptor stopping\n");
 456
 457         /* unblock lnet_acceptor_stop() */
 458         complete(&lnet_acceptor_state.pta_signal);
 459         return 0;
 460 }
 461
 462 static inline int
 463 accept2secure(const char *acc, long *sec)
 464 {
 465         if (!strcmp(acc, "secure")) {
 466                 *sec = 1;
 467                 return 1;
 468         } else if (!strcmp(acc, "all")) {
 469                 *sec = 0;
 470                 return 1;
 471         } else if (!strcmp(acc, "none")) {
 472                 return 0;
 473         } else {
 474                 LCONSOLE_ERROR_MSG(0x124, "Can't parse 'accept=\"%s\"'\n",
 475                                    acc);
 476                 return -EINVAL;
 477         }
 478 }
 479
 480 int
 481 lnet_acceptor_start(void)
 482 {
 483         struct task_struct *task;
 484         int  rc;
 485         long rc2;
 486         long secure;
 487
 488         /* if acceptor is already running return immediately */
 489         if (!lnet_acceptor_state.pta_shutdown)
 490                 return 0;
 491
 492         LASSERT(lnet_acceptor_state.pta_sock == NULL);
 493
 494         init_completion(&lnet_acceptor_state.pta_signal);
 495         rc = accept2secure(accept_type, &secure);
 496         if (rc <= 0)
 497                 return rc;
 498
 499         if (lnet_count_acceptor_nets() == 0)  /* not required */
 500                 return 0;
 501         if (current->nsproxy && current->nsproxy->net_ns)
 502                 lnet_acceptor_state.pta_ns = current->nsproxy->net_ns;
 503         else
 504                 lnet_acceptor_state.pta_ns = &init_net;
 505         task = kthread_run(lnet_acceptor, (void *)(uintptr_t)secure,
 506                            "acceptor_%03ld", secure);
 507         if (IS_ERR(task)) {
 508                 rc2 = PTR_ERR(task);
 509                 CERROR("Can't start acceptor thread: %ld\n", rc2);
 510                 return -ESRCH;
 511         }
 512
 513         /* wait for acceptor to startup */
 514         wait_for_completion(&lnet_acceptor_state.pta_signal);
 515
 516         if (!lnet_acceptor_state.pta_shutdown) {
 517                 /* started OK */
 518                 LASSERT(lnet_acceptor_state.pta_sock != NULL);
 519                 return 0;
 520         }
 521
 522         LASSERT(lnet_acceptor_state.pta_sock == NULL);
 523
 524         return -ENETDOWN;
 525 }
 526
 527 void
 528 lnet_acceptor_stop(void)
 529 {
 530         if (lnet_acceptor_state.pta_shutdown) /* not running */
 531                 return;
 532
 533         /* If still required, return immediately */
 534         if (the_lnet.ln_refcount && lnet_count_acceptor_nets() > 0)
 535                 return;
 536
 537         lnet_acceptor_state.pta_shutdown = 1;
 538         wake_up(&lnet_acceptor_state.pta_waitq);
 539
 540         /* block until acceptor signals exit */
 541         wait_for_completion(&lnet_acceptor_state.pta_signal);
 542 }