sbin/iscontrol/fsm.c

   1 /*-
   2  * Copyright (c) 2005-2008 Daniel Braniss <danny@cs.huji.ac.il>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  */
  27
  28 /*
  29  | $Id: fsm.c,v 2.8 2007/05/19 16:34:21 danny Exp danny $
  30  */
  31
  32 #include <sys/param.h>
  33 #include <sys/types.h>
  34 #include <sys/socket.h>
  35 #include <sys/sysctl.h>
  36
  37 #include <netinet/in.h>
  38 #include <netinet/tcp.h>
  39 #include <arpa/inet.h>
  40 #include <sys/ioctl.h>
  41 #include <netdb.h>
  42 #include <stdlib.h>
  43 #include <unistd.h>
  44 #include <stdio.h>
  45 #include <string.h>
  46 #include <errno.h>
  47 #include <fcntl.h>
  48 #include <time.h>
  49 #include <syslog.h>
  50 #include <stdarg.h>
  51 #include <camlib.h>
  52
  53 #include "iscsi.h"
  54 #include "iscontrol.h"
  55
  56 typedef enum {
  57      T1 = 1,
  58      T2, /*T3,*/ T4, T5, /*T6,*/ T7, T8, T9,
  59      T10, T11, T12, T13, T14, T15, T16, T18
  60 } trans_t;
  61
  62 /*
  63  | now supports IPV6
  64  | thanks to:
  65  |      Hajimu UMEMOTO @ Internet Mutual Aid Society Yokohama, Japan
  66  |      ume@mahoroba.org  ume@{,jp.}FreeBSD.org
  67  |      http://www.imasy.org/~ume/
  68  */
  69 static trans_t
  70 tcpConnect(isess_t *sess)
  71 {
  72      isc_opt_t *op = sess->op;
  73      int        val, sv_errno, soc;
  74      struct     addrinfo *res, *res0, hints;
  75      char       pbuf[10];
  76
  77      debug_called(3);
  78      if(sess->flags & (SESS_RECONNECT|SESS_REDIRECT)) {
  79           syslog(LOG_INFO, "%s", (sess->flags & SESS_RECONNECT)
  80                  ? "Reconnect": "Redirected");
  81
  82           debug(1, "%s", (sess->flags & SESS_RECONNECT) ? "Reconnect": "Redirected");
  83           shutdown(sess->soc, SHUT_RDWR);
  84           //close(sess->soc);
  85           sess->soc = -1;
  86
  87           sess->flags &= ~SESS_CONNECTED;
  88           if(sess->flags & SESS_REDIRECT) {
  89                sess->redirect_cnt++;
  90                sess->flags |= SESS_RECONNECT;
  91           } else
  92                sleep(2); // XXX: actually should be ?
  93 #ifdef notyet
  94           {
  95                time_t   sec;
  96           // make sure we are not in a loop
  97           // XXX: this code has to be tested
  98           sec = time(0) - sess->reconnect_time;
  99           if(sec > (5*60)) {
 100                // if we've been connected for more that 5 minutes
 101                // then just reconnect
 102                sess->reconnect_time = sec;
 103                sess->reconnect_cnt1 = 0;
 104           }
 105           else {
 106                //
 107                sess->reconnect_cnt1++;
 108                if((sec / sess->reconnect_cnt1) < 2) {
 109                     // if less that 2 seconds from the last reconnect
 110                     // we are most probably looping
 111                     syslog(LOG_CRIT, "too many reconnects %d", sess->reconnect_cnt1);
 112                     return 0;
 113                }
 114           }
 115      }
 116 #endif
 117           sess->reconnect_cnt++;
 118      }
 119
 120      snprintf(pbuf, sizeof(pbuf), "%d", op->port);
 121      memset(&hints, 0, sizeof(hints));
 122      hints.ai_family    = PF_UNSPEC;
 123      hints.ai_socktype  = SOCK_STREAM;
 124      debug(1, "targetAddress=%s port=%d", op->targetAddress, op->port);
 125      if((val = getaddrinfo(op->targetAddress, pbuf, &hints, &res0)) != 0) {
 126           fprintf(stderr, "getaddrinfo(%s): %s\n", op->targetAddress, gai_strerror(val));
 127           return 0;
 128      }
 129      sess->flags &= ~SESS_CONNECTED;
 130      sv_errno = 0;
 131      soc = -1;
 132      for(res = res0; res; res = res->ai_next) {
 133           soc = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
 134           if (soc == -1)
 135                continue;
 136
 137      // from Patrick.Guelat@imp.ch:
 138      // iscontrol can be called without waiting for the socket entry to time out
 139           val = 1;
 140           if(setsockopt(soc, SOL_SOCKET, SO_REUSEADDR, &val, (socklen_t)sizeof(val)) < 0) {
 141                   fprintf(stderr, "Cannot set socket SO_REUSEADDR %d: %s\n\n",
 142                                   errno, strerror(errno));
 143           }
 144           if(connect(soc, res->ai_addr, res->ai_addrlen) == 0)
 145              break;
 146
 147           sv_errno = errno;
 148           close(soc);
 149           soc = -1;
 150      }
 151      freeaddrinfo(res0);
 152
 153      if(soc != -1) {
 154           sess->soc = soc;
 155
 156           /* Default to TCP_NODELAY to improve transfers */
 157           if(setsockopt(sess->soc, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) < 0)
 158                   fprintf(stderr, "Cannot set socket NO delay option err=%d %s\n",
 159                                   errno, strerror(errno));
 160
 161 #if 0
 162           struct        timeval timeout;
 163
 164           val = 1;
 165           if(setsockopt(sess->soc, IPPROTO_TCP, TCP_KEEPALIVE, &val, sizeof(val)) < 0)
 166                fprintf(stderr, "Cannot set socket KEEPALIVE option err=%d %s\n",
 167                        errno, strerror(errno));
 168
 169           if(setsockopt(sess->soc, IPPROTO_TCP, TCP_NODELAY, &val, sizeof(val)) < 0)
 170                fprintf(stderr, "Cannot set socket NO delay option err=%d %s\n",
 171                        errno, strerror(errno));
 172
 173           timeout.tv_sec = 10;
 174           timeout.tv_usec = 0;
 175           if((setsockopt(sess->soc, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout)) < 0)
 176              || (setsockopt(sess->soc, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout)) < 0)) {
 177                fprintf(stderr, "Cannot set socket timeout to %ld err=%d %s\n",
 178                        timeout.tv_sec, errno, strerror(errno));
 179           }
 180 #endif
 181 #ifdef CURIOUS
 182           {
 183                int len = sizeof(val);
 184                if(getsockopt(sess->soc, SOL_SOCKET, SO_SNDBUF, &val, &len) == 0)
 185                     fprintf(stderr, "was: SO_SNDBUF=%dK\n", val/1024);
 186           }
 187 #endif
 188           if(sess->op->sockbufsize) {
 189                val = sess->op->sockbufsize * 1024;
 190                if((setsockopt(sess->soc, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)) < 0)
 191                   || (setsockopt(sess->soc, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)) < 0)) {
 192                     fprintf(stderr, "Cannot set socket sndbuf & rcvbuf to %d err=%d %s\n",
 193                             val, errno, strerror(errno));
 194                     return 0;
 195                }
 196           }
 197           sess->flags |= SESS_CONNECTED;
 198           return T1;
 199      }
 200
 201      fprintf(stderr, "errno=%d\n", sv_errno);
 202      perror("connect");
 203      switch(sv_errno) {
 204      case ECONNREFUSED:
 205      case ENETUNREACH:
 206      case ETIMEDOUT:
 207           if((sess->flags & SESS_REDIRECT) == 0) {
 208                if(strcmp(op->targetAddress, sess->target.address) != 0) {
 209                     syslog(LOG_INFO, "reconnecting to original target address");
 210                     free(op->targetAddress);
 211                     op->targetAddress           = sess->target.address;
 212                     op->port                    = sess->target.port;
 213                     op->targetPortalGroupTag    = sess->target.pgt;
 214                     return T1;
 215                }
 216           }
 217           sleep(5); // for now ...
 218           return T1;
 219      default:
 220           return 0; // terminal error
 221      }
 222 }
 223
 224 int
 225 setOptions(isess_t *sess, int flag)
 226 {
 227      isc_opt_t  oop;
 228      char       *sep;
 229
 230      debug_called(3);
 231
 232      bzero(&oop, sizeof(isc_opt_t));
 233
 234      if((flag & SESS_FULLFEATURE) == 0) {
 235           oop.initiatorName     = sess->op->initiatorName;
 236           oop.targetAddress     = sess->op->targetAddress;
 237           if(sess->op->targetName != 0)
 238                oop.targetName = sess->op->targetName;
 239
 240           oop.maxRecvDataSegmentLength = sess->op->maxRecvDataSegmentLength;
 241           oop.maxXmitDataSegmentLength = sess->op->maxXmitDataSegmentLength; // XXX:
 242           oop.maxBurstLength = sess->op->maxBurstLength;
 243           oop.maxluns = sess->op->maxluns;
 244      }
 245      else {
 246           /*
 247            | turn on digestion only after login
 248            */
 249           if(sess->op->headerDigest != NULL) {
 250                sep = strchr(sess->op->headerDigest, ',');
 251                if(sep == NULL)
 252                     oop.headerDigest = sess->op->headerDigest;
 253                debug(1, "oop.headerDigest=%s", oop.headerDigest);
 254           }
 255           if(sess->op->dataDigest != NULL) {
 256                sep = strchr(sess->op->dataDigest, ',');
 257                if(sep == NULL)
 258                     oop.dataDigest = sess->op->dataDigest;
 259                debug(1, "oop.dataDigest=%s", oop.dataDigest);
 260           }
 261      }
 262
 263      if(ioctl(sess->fd, ISCSISETOPT, &oop)) {
 264           perror("ISCSISETOPT");
 265           return -1;
 266      }
 267      return 0;
 268 }
 269
 270 static trans_t
 271 startSession(isess_t *sess)
 272 {
 273
 274      int        n, fd, nfd;
 275      char       *dev;
 276
 277      debug_called(3);
 278
 279      if((sess->flags & SESS_CONNECTED) == 0) {
 280           return T2;
 281      }
 282      if(sess->fd == -1) {
 283           fd = open(iscsidev, O_RDWR);
 284           if(fd < 0) {
 285                perror(iscsidev);
 286                return 0;
 287           }
 288           {
 289                // XXX: this has to go
 290                size_t   n;
 291                n = sizeof(sess->isid);
 292                if(sysctlbyname("net.iscsi.isid", (void *)sess->isid, (size_t *)&n, 0, 0) != 0)
 293                     perror("sysctlbyname");
 294           }
 295           if(ioctl(fd, ISCSISETSES, &n)) {
 296                perror("ISCSISETSES");
 297                return 0;
 298           }
 299           sleep(1);     /* XXX temporary */
 300           asprintf(&dev, "%s%d", iscsidev, n);
 301           nfd = open(dev, O_RDWR);
 302           if(nfd < 0) {
 303                perror(dev);
 304                free(dev);
 305                return 0;
 306           }
 307           free(dev);
 308           close(fd);
 309           sess->fd = nfd;
 310
 311           if(setOptions(sess, 0) != 0)
 312                return -1;
 313      }
 314
 315      if(ioctl(sess->fd, ISCSISETSOC, &sess->soc)) {
 316           perror("ISCSISETSOC");
 317           return 0;
 318      }
 319
 320      return T4;
 321 }
 322
 323 isess_t *currsess;
 324
 325 static void
 326 trap(int sig)
 327 {
 328      syslog(LOG_NOTICE, "trapped signal %d", sig);
 329      fprintf(stderr, "trapped signal %d\n", sig);
 330
 331      switch(sig) {
 332      case SIGHUP:
 333           currsess->flags |= SESS_DISCONNECT;
 334           break;
 335
 336      case SIGUSR1:
 337           currsess->flags |= SESS_RECONNECT;
 338           break;
 339
 340      case SIGINT:
 341      case SIGTERM:
 342      default:
 343           return; // ignore
 344      }
 345 }
 346
 347 static void
 348 doCAM(isess_t *sess)
 349 {
 350      char       pathstr[1024];
 351      union ccb  *ccb;
 352      int        i;
 353
 354      if(ioctl(sess->fd, ISCSIGETCAM, &sess->cam) != 0) {
 355           syslog(LOG_WARNING, "ISCSIGETCAM failed: %d", errno);
 356           return;
 357      }
 358      debug(2, "nluns=%d", sess->cam.target_nluns);
 359      /*
 360       | for now will do this for each lun ...
 361       */
 362      for(i = 0; i < sess->cam.target_nluns; i++) {
 363           debug(2, "CAM path_id=%d target_id=%d target_lun=%d",
 364                 sess->cam.path_id, sess->cam.target_id, sess->cam.target_lun[i]);
 365
 366           sess->camdev = cam_open_btl(sess->cam.path_id, sess->cam.target_id,
 367                                       sess->cam.target_lun[i], O_RDWR, NULL);
 368           if(sess->camdev == NULL) {
 369                syslog(LOG_WARNING, "%s", cam_errbuf);
 370                debug(3, "%s", cam_errbuf);
 371                continue;
 372           }
 373
 374           cam_path_string(sess->camdev, pathstr, sizeof(pathstr));
 375           debug(2, "pathstr=%s", pathstr);
 376
 377           ccb = cam_getccb(sess->camdev);
 378           bzero(&(&ccb->ccb_h)[1], sizeof(struct ccb_relsim) - sizeof(struct ccb_hdr));
 379           ccb->ccb_h.func_code = XPT_REL_SIMQ;
 380           ccb->crs.release_flags = RELSIM_ADJUST_OPENINGS;
 381           ccb->crs.openings = sess->op->tags;
 382
 383           if(cam_send_ccb(sess->camdev, ccb) < 0)
 384                syslog(LOG_WARNING, "%s", cam_errbuf);
 385           else
 386           if((ccb->ccb_h.status & CAM_STATUS_MASK) != CAM_REQ_CMP) {
 387                syslog(LOG_WARNING, "XPT_REL_SIMQ CCB failed");
 388                // cam_error_print(sess->camdev, ccb, CAM_ESF_ALL, CAM_EPF_ALL, stderr);
 389           }
 390           else
 391                syslog(LOG_INFO, "%s tagged openings now %d\n", pathstr, ccb->crs.openings);
 392
 393           cam_freeccb(ccb);
 394           cam_close_device(sess->camdev);
 395      }
 396 }
 397
 398 static trans_t
 399 supervise(isess_t *sess)
 400 {
 401      int        sig, val;
 402
 403      debug_called(3);
 404
 405      if(strcmp(sess->op->sessionType, "Discovery") == 0) {
 406           sess->flags |= SESS_DISCONNECT;
 407           return T9;
 408      }
 409
 410      if(vflag)
 411           printf("ready to go scsi\n");
 412
 413      if(setOptions(sess, SESS_FULLFEATURE) != 0)
 414           return 0; // failure
 415
 416      if((sess->flags & SESS_FULLFEATURE) == 0) {
 417           if(daemon(0, 1) != 0) {
 418                perror("daemon");
 419                exit(1);
 420           }
 421
 422           openlog("iscontrol", LOG_CONS|LOG_PERROR|LOG_PID|LOG_NDELAY, LOG_KERN);
 423           syslog(LOG_INFO, "running");
 424
 425           currsess = sess;
 426           if(ioctl(sess->fd, ISCSISTART)) {
 427                perror("ISCSISTART");
 428                return -1;
 429           }
 430           doCAM(sess);
 431
 432      }
 433      else {
 434           if(ioctl(sess->fd, ISCSIRESTART)) {
 435                perror("ISCSIRESTART");
 436                return -1;
 437           }
 438      }
 439
 440      signal(SIGINT, trap);
 441      signal(SIGHUP, trap);
 442      signal(SIGTERM, trap);
 443
 444      sig = SIGUSR1;
 445      signal(sig, trap);
 446      if(ioctl(sess->fd, ISCSISIGNAL, &sig)) {
 447           perror("ISCSISIGNAL");
 448           return -1;
 449      }
 450      sess->flags |= SESS_FULLFEATURE;
 451
 452      sess->flags &= ~(SESS_REDIRECT | SESS_RECONNECT);
 453      printf("iscontrol: supervise starting main loop\n");
 454      /*
 455       | the main loop - actually do nothing
 456       | all the work is done inside the kernel
 457       */
 458      while((sess->flags & (SESS_REDIRECT|SESS_RECONNECT|SESS_DISCONNECT)) == 0) {
 459           // do something?
 460           // like sending a nop_out?
 461           sleep(60);
 462      }
 463      printf("iscontrol: supervise going down\n");
 464      syslog(LOG_INFO, "sess flags=%x", sess->flags);
 465
 466      sig = 0;
 467      if(ioctl(sess->fd, ISCSISIGNAL, &sig)) {
 468           perror("ISCSISIGNAL");
 469      }
 470
 471      if(sess->flags & SESS_DISCONNECT) {
 472           val = 0;
 473           if(ioctl(sess->fd, ISCSISTOP, &val)) {
 474                perror("ISCSISTOP");
 475           }
 476           sess->flags &= ~SESS_FULLFEATURE;
 477           return T9;
 478      }
 479      else {
 480           sess->flags |= SESS_INITIALLOGIN1;
 481      }
 482      return T8;
 483 }
 484
 485 static int
 486 handledDiscoveryResp(isess_t *sess, pdu_t *pp)
 487 {
 488      u_char     *ptr;
 489      int        len, n;
 490
 491      debug_called(3);
 492
 493      len = pp->ds_len;
 494      ptr = pp->ds;
 495      while(len > 0) {
 496           if(*ptr != 0)
 497                printf("%s\n", ptr);
 498           n = strlen((char *)ptr) + 1;
 499           len -= n;
 500           ptr += n;
 501      }
 502      return 0;
 503 }
 504
 505 static int
 506 doDiscovery(isess_t *sess)
 507 {
 508      pdu_t      spp;
 509      text_req_t *tp = (text_req_t *)&spp.ipdu.bhs;
 510
 511      debug_called(3);
 512
 513      bzero(&spp, sizeof(pdu_t));
 514      tp->cmd = ISCSI_TEXT_CMD /*| 0x40 */; // because of a bug in openiscsi-target
 515      tp->F = 1;
 516      tp->ttt = 0xffffffff;
 517      addText(&spp, "SendTargets=All");
 518      return sendPDU(sess, &spp, handledDiscoveryResp);
 519 }
 520
 521 static trans_t
 522 doLogin(isess_t *sess)
 523 {
 524      isc_opt_t  *op = sess->op;
 525      int        status, count;
 526
 527      debug_called(3);
 528
 529      if(op->chapSecret == NULL && op->tgtChapSecret == NULL)
 530           /*
 531            | don't need any security negotiation
 532            | or in other words: we don't have any secrets to exchange
 533            */
 534           sess->csg = LON_PHASE;
 535      else
 536           sess->csg = SN_PHASE;
 537
 538      if(sess->tsih) {
 539           sess->tsih = 0;       // XXX: no 'reconnect' yet
 540           sess->flags &= ~SESS_NEGODONE; // XXX: KLUDGE
 541      }
 542      count = 10; // should be more than enough
 543      do {
 544           debug(3, "count=%d csg=%d", count, sess->csg);
 545           status = loginPhase(sess);
 546           if(count-- == 0)
 547                // just in case we get into a loop
 548                status = -1;
 549      } while(status == 0 && (sess->csg != FF_PHASE));
 550
 551      sess->flags &= ~SESS_INITIALLOGIN;
 552      debug(3, "status=%d", status);
 553
 554      switch(status) {
 555      case 0: // all is ok ...
 556           sess->flags |= SESS_LOGGEDIN;
 557           if(strcmp(sess->op->sessionType, "Discovery") == 0)
 558                doDiscovery(sess);
 559           return T5;
 560
 561      case 1:    // redirect - temporary/permanent
 562           /*
 563            | start from scratch?
 564            */
 565           sess->flags &= ~SESS_NEGODONE;
 566           sess->flags |= (SESS_REDIRECT | SESS_INITIALLOGIN1);
 567           syslog(LOG_DEBUG, "target sent REDIRECT");
 568           return T7;
 569
 570      case 2: // initiator terminal error
 571           return 0;
 572      case 3: // target terminal error -- could retry ...
 573           sleep(5);
 574           return T7; // lets try
 575      default:
 576           return 0;
 577      }
 578 }
 579
 580 static int
 581 handleLogoutResp(isess_t *sess, pdu_t *pp)
 582 {
 583      if(sess->flags & SESS_DISCONNECT)
 584           return 0;
 585      return T13;
 586 }
 587
 588 static trans_t
 589 startLogout(isess_t *sess)
 590 {
 591      pdu_t      spp;
 592      logout_req_t *p = (logout_req_t *)&spp.ipdu.bhs;
 593
 594      bzero(&spp, sizeof(pdu_t));
 595      p->cmd = ISCSI_LOGOUT_CMD| 0x40;
 596      p->reason = BIT(7) | 0;
 597      p->CID = htons(1);
 598
 599      return sendPDU(sess, &spp, handleLogoutResp);
 600 }
 601
 602 static trans_t
 603 inLogout(isess_t *sess)
 604 {
 605      if(sess->flags & SESS_RECONNECT)
 606           return T18;
 607      return 0;
 608 }
 609
 610 typedef enum {
 611      S1=1, S2, S3, S4, S5, S6, S7, S8
 612 } state_t;
 613 \f
 614 #if 0
 615       S1: FREE
 616       S2: XPT_WAIT
 617       S4: IN_LOGIN
 618       S5: LOGGED_IN
 619       S6: IN_LOGOUT
 620       S7: LOGOUT_REQUESTED
 621       S8: CLEANUP_WAIT
 622
 623                      -------<-------------+
 624          +--------->/ S1    \<----+       |
 625       T13|       +->\       /<-+   \      |
 626          |      /    ---+---    \   \     |
 627          |     /        |     T2 \   |    |
 628          |  T8 |        |T1       |  |    |
 629          |     |        |        /   |T7  |
 630          |     |        |       /    |    |
 631          |     |        |      /     |    |
 632          |     |        V     /     /     |
 633          |     |     ------- /     /      |
 634          |     |    / S2    \     /       |
 635          |     |    \       /    /        |
 636          |     |     ---+---    /         |
 637          |     |        |T4    /          |
 638          |     |        V     /           | T18
 639          |     |     ------- /            |
 640          |     |    / S4    \             |
 641          |     |    \       /             |
 642          |     |     ---+---              |         T15
 643          |     |        |T5      +--------+---------+
 644          |     |        |       /T16+-----+------+  |
 645          |     |        |      /   -+-----+--+   |  |
 646          |     |        |     /   /  S7   \  |T12|  |
 647          |     |        |    / +->\       /<-+   V  V
 648          |     |        |   / /    -+-----       -------
 649          |     |        |  / /T11   |T10        /  S8   \
 650          |     |        V / /       V  +----+   \       /
 651          |     |      ---+-+-      ----+--  |    -------
 652          |     |     / S5    \T9  / S6    \<+    ^
 653          |     +-----\       /--->\       / T14  |
 654          |            -------      --+----+------+T17
 655          +---------------------------+
 656 #endif
 657
 658 int
 659 fsm(isc_opt_t *op)
 660 {
 661      state_t    state;
 662      isess_t    *sess;
 663
 664      if((sess = calloc(1, sizeof(isess_t))) == NULL) {
 665           // boy, is this a bad start ...
 666           fprintf(stderr, "no memory!\n");
 667           return -1;
 668      }
 669
 670      state = S1;
 671      sess->op = op;
 672      sess->fd = -1;
 673      sess->soc = -1;
 674      sess->target.address = strdup(op->targetAddress);
 675      sess->target.port = op->port;
 676      sess->target.pgt = op->targetPortalGroupTag;
 677
 678      sess->flags = SESS_INITIALLOGIN | SESS_INITIALLOGIN1;
 679
 680      do {
 681           switch(state) {
 682           case S1:
 683                switch(tcpConnect(sess)) {
 684                case T1: state = S2; break;
 685                default: state = S8; break;
 686                }
 687                break;
 688
 689           case S2:
 690                switch(startSession(sess)) {
 691                case T2: state = S1; break;
 692                case T4: state = S4; break;
 693                default: state = S8; break;
 694                }
 695                break;
 696
 697           case S4:
 698                switch(doLogin(sess)) {
 699                case T7:  state = S1; break;
 700                case T5:  state = S5; break;
 701                default: state = S8; break;
 702                }
 703                break;
 704
 705           case S5:
 706                switch(supervise(sess)) {
 707                case T8:  state = S1; break;
 708                case T9:  state = S6; break;
 709                case T11: state = S7; break;
 710                case T15: state = S8; break;
 711                default: state = S8; break;
 712                }
 713                break;
 714
 715           case S6:
 716                switch(startLogout(sess)) {
 717                case T13: state = S1; break;
 718                case T14: state = S6; break;
 719                case T16: state = S8; break;
 720                default: state = S8; break;
 721                }
 722                break;
 723
 724           case S7:
 725                switch(inLogout(sess)) {
 726                case T18: state = S1; break;
 727                case T10: state = S6; break;
 728                case T12: state = S7; break;
 729                case T16: state = S8; break;
 730                default: state = S8; break;
 731                }
 732                break;
 733
 734           case S8:
 735                // maybe do some clean up?
 736                syslog(LOG_INFO, "terminated");
 737                return 0;
 738           default:
 739                syslog(LOG_INFO, "unknown state %d", state);
 740                return 0;
 741           }
 742      } while(1);
 743 }