mdw@git.distorted.org.uk Git - sgt/putty/blob - windows/winplink.c

   1 /*
   2  * PLink - a Windows command-line (stdin/stdout) variant of PuTTY.
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <assert.h>
   8 #include <stdarg.h>
   9
  10 #define PUTTY_DO_GLOBALS               /* actually _define_ globals */
  11 #include "putty.h"
  12 #include "storage.h"
  13 #include "tree234.h"
  14
  15 #define WM_AGENT_CALLBACK (WM_APP + 4)
  16
  17 struct agent_callback {
  18     void (*callback)(void *, void *, int);
  19     void *callback_ctx;
  20     void *data;
  21     int len;
  22 };
  23
  24 void fatalbox(char *p, ...)
  25 {
  26     va_list ap;
  27     fprintf(stderr, "FATAL ERROR: ");
  28     va_start(ap, p);
  29     vfprintf(stderr, p, ap);
  30     va_end(ap);
  31     fputc('\n', stderr);
  32     if (logctx) {
  33         log_free(logctx);
  34         logctx = NULL;
  35     }
  36     cleanup_exit(1);
  37 }
  38 void modalfatalbox(char *p, ...)
  39 {
  40     va_list ap;
  41     fprintf(stderr, "FATAL ERROR: ");
  42     va_start(ap, p);
  43     vfprintf(stderr, p, ap);
  44     va_end(ap);
  45     fputc('\n', stderr);
  46     if (logctx) {
  47         log_free(logctx);
  48         logctx = NULL;
  49     }
  50     cleanup_exit(1);
  51 }
  52 void connection_fatal(void *frontend, char *p, ...)
  53 {
  54     va_list ap;
  55     fprintf(stderr, "FATAL ERROR: ");
  56     va_start(ap, p);
  57     vfprintf(stderr, p, ap);
  58     va_end(ap);
  59     fputc('\n', stderr);
  60     if (logctx) {
  61         log_free(logctx);
  62         logctx = NULL;
  63     }
  64     cleanup_exit(1);
  65 }
  66 void cmdline_error(char *p, ...)
  67 {
  68     va_list ap;
  69     fprintf(stderr, "plink: ");
  70     va_start(ap, p);
  71     vfprintf(stderr, p, ap);
  72     va_end(ap);
  73     fputc('\n', stderr);
  74     exit(1);
  75 }
  76
  77 HANDLE inhandle, outhandle, errhandle;
  78 struct handle *stdin_handle, *stdout_handle, *stderr_handle;
  79 DWORD orig_console_mode;
  80 int connopen;
  81
  82 WSAEVENT netevent;
  83
  84 static Backend *back;
  85 static void *backhandle;
  86 static Conf *conf;
  87
  88 int term_ldisc(Terminal *term, int mode)
  89 {
  90     return FALSE;
  91 }
  92 void ldisc_update(void *frontend, int echo, int edit)
  93 {
  94     /* Update stdin read mode to reflect changes in line discipline. */
  95     DWORD mode;
  96
  97     mode = ENABLE_PROCESSED_INPUT;
  98     if (echo)
  99         mode = mode | ENABLE_ECHO_INPUT;
 100     else
 101         mode = mode & ~ENABLE_ECHO_INPUT;
 102     if (edit)
 103         mode = mode | ENABLE_LINE_INPUT;
 104     else
 105         mode = mode & ~ENABLE_LINE_INPUT;
 106     SetConsoleMode(inhandle, mode);
 107 }
 108
 109 char *get_ttymode(void *frontend, const char *mode) { return NULL; }
 110
 111 int from_backend(void *frontend_handle, int is_stderr,
 112                  const char *data, int len)
 113 {
 114     if (is_stderr) {
 115         handle_write(stderr_handle, data, len);
 116     } else {
 117         handle_write(stdout_handle, data, len);
 118     }
 119
 120     return handle_backlog(stdout_handle) + handle_backlog(stderr_handle);
 121 }
 122
 123 int from_backend_untrusted(void *frontend_handle, const char *data, int len)
 124 {
 125     /*
 126      * No "untrusted" output should get here (the way the code is
 127      * currently, it's all diverted by FLAG_STDERR).
 128      */
 129     assert(!"Unexpected call to from_backend_untrusted()");
 130     return 0; /* not reached */
 131 }
 132
 133 int from_backend_eof(void *frontend_handle)
 134 {
 135     handle_write_eof(stdout_handle);
 136     return FALSE;   /* do not respond to incoming EOF with outgoing */
 137 }
 138
 139 int get_userpass_input(prompts_t *p, unsigned char *in, int inlen)
 140 {
 141     int ret;
 142     ret = cmdline_get_passwd_input(p, in, inlen);
 143     if (ret == -1)
 144         ret = console_get_userpass_input(p, in, inlen);
 145     return ret;
 146 }
 147
 148 static DWORD main_thread_id;
 149
 150 void agent_schedule_callback(void (*callback)(void *, void *, int),
 151                              void *callback_ctx, void *data, int len)
 152 {
 153     struct agent_callback *c = snew(struct agent_callback);
 154     c->callback = callback;
 155     c->callback_ctx = callback_ctx;
 156     c->data = data;
 157     c->len = len;
 158     PostThreadMessage(main_thread_id, WM_AGENT_CALLBACK, 0, (LPARAM)c);
 159 }
 160
 161 /*
 162  *  Short description of parameters.
 163  */
 164 static void usage(void)
 165 {
 166     printf("PuTTY Link: command-line connection utility\n");
 167     printf("%s\n", ver);
 168     printf("Usage: plink [options] [user@]host [command]\n");
 169     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 170     printf("Options:\n");
 171     printf("  -V        print version information and exit\n");
 172     printf("  -pgpfp    print PGP key fingerprints and exit\n");
 173     printf("  -v        show verbose messages\n");
 174     printf("  -load sessname  Load settings from saved session\n");
 175     printf("  -ssh -telnet -rlogin -raw -serial\n");
 176     printf("            force use of a particular protocol\n");
 177     printf("  -P port   connect to specified port\n");
 178     printf("  -l user   connect with specified username\n");
 179     printf("  -batch    disable all interactive prompts\n");
 180     printf("The following options only apply to SSH connections:\n");
 181     printf("  -pw passw login with specified password\n");
 182     printf("  -D [listen-IP:]listen-port\n");
 183     printf("            Dynamic SOCKS-based port forwarding\n");
 184     printf("  -L [listen-IP:]listen-port:host:port\n");
 185     printf("            Forward local port to remote address\n");
 186     printf("  -R [listen-IP:]listen-port:host:port\n");
 187     printf("            Forward remote port to local address\n");
 188     printf("  -X -x     enable / disable X11 forwarding\n");
 189     printf("  -A -a     enable / disable agent forwarding\n");
 190     printf("  -t -T     enable / disable pty allocation\n");
 191     printf("  -1 -2     force use of particular protocol version\n");
 192     printf("  -4 -6     force use of IPv4 or IPv6\n");
 193     printf("  -C        enable compression\n");
 194     printf("  -i key    private key file for authentication\n");
 195     printf("  -noagent  disable use of Pageant\n");
 196     printf("  -agent    enable use of Pageant\n");
 197     printf("  -m file   read remote command(s) from file\n");
 198     printf("  -s        remote command is an SSH subsystem (SSH-2 only)\n");
 199     printf("  -N        don't start a shell/command (SSH-2 only)\n");
 200     printf("  -nc host:port\n");
 201     printf("            open tunnel in place of session (SSH-2 only)\n");
 202     printf("  -sercfg configuration-string (e.g. 19200,8,n,1,X)\n");
 203     printf("            Specify the serial configuration (serial only)\n");
 204     exit(1);
 205 }
 206
 207 static void version(void)
 208 {
 209     printf("plink: %s\n", ver);
 210     exit(1);
 211 }
 212
 213 char *do_select(SOCKET skt, int startup)
 214 {
 215     int events;
 216     if (startup) {
 217         events = (FD_CONNECT | FD_READ | FD_WRITE |
 218                   FD_OOB | FD_CLOSE | FD_ACCEPT);
 219     } else {
 220         events = 0;
 221     }
 222     if (p_WSAEventSelect(skt, netevent, events) == SOCKET_ERROR) {
 223         switch (p_WSAGetLastError()) {
 224           case WSAENETDOWN:
 225             return "Network is down";
 226           default:
 227             return "WSAEventSelect(): unknown error";
 228         }
 229     }
 230     return NULL;
 231 }
 232
 233 int stdin_gotdata(struct handle *h, void *data, int len)
 234 {
 235     if (len < 0) {
 236         /*
 237          * Special case: report read error.
 238          */
 239         char buf[4096];
 240         FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, -len, 0,
 241                       buf, lenof(buf), NULL);
 242         buf[lenof(buf)-1] = '\0';
 243         if (buf[strlen(buf)-1] == '\n')
 244             buf[strlen(buf)-1] = '\0';
 245         fprintf(stderr, "Unable to read from standard input: %s\n", buf);
 246         cleanup_exit(0);
 247     }
 248     noise_ultralight(len);
 249     if (connopen && back->connected(backhandle)) {
 250         if (len > 0) {
 251             return back->send(backhandle, data, len);
 252         } else {
 253             back->special(backhandle, TS_EOF);
 254             return 0;
 255         }
 256     } else
 257         return 0;
 258 }
 259
 260 void stdouterr_sent(struct handle *h, int new_backlog)
 261 {
 262     if (new_backlog < 0) {
 263         /*
 264          * Special case: report write error.
 265          */
 266         char buf[4096];
 267         FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, -new_backlog, 0,
 268                       buf, lenof(buf), NULL);
 269         buf[lenof(buf)-1] = '\0';
 270         if (buf[strlen(buf)-1] == '\n')
 271             buf[strlen(buf)-1] = '\0';
 272         fprintf(stderr, "Unable to write to standard %s: %s\n",
 273                 (h == stdout_handle ? "output" : "error"), buf);
 274         cleanup_exit(0);
 275     }
 276     if (connopen && back->connected(backhandle)) {
 277         back->unthrottle(backhandle, (handle_backlog(stdout_handle) +
 278                                       handle_backlog(stderr_handle)));
 279     }
 280 }
 281
 282 int main(int argc, char **argv)
 283 {
 284     int sending;
 285     int portnumber = -1;
 286     SOCKET *sklist;
 287     int skcount, sksize;
 288     int exitcode;
 289     int errors;
 290     int got_host = FALSE;
 291     int use_subsystem = 0;
 292     unsigned long now, next, then;
 293
 294     sklist = NULL;
 295     skcount = sksize = 0;
 296     /*
 297      * Initialise port and protocol to sensible defaults. (These
 298      * will be overridden by more or less anything.)
 299      */
 300     default_protocol = PROT_SSH;
 301     default_port = 22;
 302
 303     flags = FLAG_STDERR;
 304     /*
 305      * Process the command line.
 306      */
 307     conf = conf_new();
 308     do_defaults(NULL, conf);
 309     loaded_session = FALSE;
 310     default_protocol = conf_get_int(conf, CONF_protocol);
 311     default_port = conf_get_int(conf, CONF_port);
 312     errors = 0;
 313     {
 314         /*
 315          * Override the default protocol if PLINK_PROTOCOL is set.
 316          */
 317         char *p = getenv("PLINK_PROTOCOL");
 318         if (p) {
 319             const Backend *b = backend_from_name(p);
 320             if (b) {
 321                 default_protocol = b->protocol;
 322                 default_port = b->default_port;
 323                 conf_set_int(conf, CONF_protocol, default_protocol);
 324                 conf_set_int(conf, CONF_port, default_port);
 325             }
 326         }
 327     }
 328     while (--argc) {
 329         char *p = *++argv;
 330         if (*p == '-') {
 331             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL),
 332                                             1, conf);
 333             if (ret == -2) {
 334                 fprintf(stderr,
 335                         "plink: option \"%s\" requires an argument\n", p);
 336                 errors = 1;
 337             } else if (ret == 2) {
 338                 --argc, ++argv;
 339             } else if (ret == 1) {
 340                 continue;
 341             } else if (!strcmp(p, "-batch")) {
 342                 console_batch_mode = 1;
 343             } else if (!strcmp(p, "-s")) {
 344                 /* Save status to write to conf later. */
 345                 use_subsystem = 1;
 346             } else if (!strcmp(p, "-V")) {
 347                 version();
 348             } else if (!strcmp(p, "-pgpfp")) {
 349                 pgp_fingerprints();
 350                 exit(1);
 351             } else {
 352                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 353                 errors = 1;
 354             }
 355         } else if (*p) {
 356             if (!conf_launchable(conf) || !(got_host || loaded_session)) {
 357                 char *q = p;
 358                 /*
 359                  * If the hostname starts with "telnet:", set the
 360                  * protocol to Telnet and process the string as a
 361                  * Telnet URL.
 362                  */
 363                 if (!strncmp(q, "telnet:", 7)) {
 364                     char c;
 365
 366                     q += 7;
 367                     if (q[0] == '/' && q[1] == '/')
 368                         q += 2;
 369                     conf_set_int(conf, CONF_protocol, PROT_TELNET);
 370                     p = q;
 371                     while (*p && *p != ':' && *p != '/')
 372                         p++;
 373                     c = *p;
 374                     if (*p)
 375                         *p++ = '\0';
 376                     if (c == ':')
 377                         conf_set_int(conf, CONF_port, atoi(p));
 378                     else
 379                         conf_set_int(conf, CONF_port, -1);
 380                     conf_set_str(conf, CONF_host, q);
 381                     got_host = TRUE;
 382                 } else {
 383                     char *r, *user, *host;
 384                     /*
 385                      * Before we process the [user@]host string, we
 386                      * first check for the presence of a protocol
 387                      * prefix (a protocol name followed by ",").
 388                      */
 389                     r = strchr(p, ',');
 390                     if (r) {
 391                         const Backend *b;
 392                         *r = '\0';
 393                         b = backend_from_name(p);
 394                         if (b) {
 395                             default_protocol = b->protocol;
 396                             conf_set_int(conf, CONF_protocol,
 397                                          default_protocol);
 398                             portnumber = b->default_port;
 399                         }
 400                         p = r + 1;
 401                     }
 402
 403                     /*
 404                      * A nonzero length string followed by an @ is treated
 405                      * as a username. (We discount an _initial_ @.) The
 406                      * rest of the string (or the whole string if no @)
 407                      * is treated as a session name and/or hostname.
 408                      */
 409                     r = strrchr(p, '@');
 410                     if (r == p)
 411                         p++, r = NULL; /* discount initial @ */
 412                     if (r) {
 413                         *r++ = '\0';
 414                         user = p, host = r;
 415                     } else {
 416                         user = NULL, host = p;
 417                     }
 418
 419                     /*
 420                      * Now attempt to load a saved session with the
 421                      * same name as the hostname.
 422                      */
 423                     {
 424                         Conf *conf2 = conf_new();
 425                         do_defaults(host, conf2);
 426                         if (loaded_session || !conf_launchable(conf2)) {
 427                             /* No settings for this host; use defaults */
 428                             /* (or session was already loaded with -load) */
 429                             conf_set_str(conf, CONF_host, host);
 430                             conf_set_int(conf, CONF_port, default_port);
 431                             got_host = TRUE;
 432                         } else {
 433                             conf_copy_into(conf, conf2);
 434                             loaded_session = TRUE;
 435                         }
 436                         conf_free(conf2);
 437                     }
 438
 439                     if (user) {
 440                         /* Patch in specified username. */
 441                         conf_set_str(conf, CONF_username, user);
 442                     }
 443
 444                 }
 445             } else {
 446                 char *command;
 447                 int cmdlen, cmdsize;
 448                 cmdlen = cmdsize = 0;
 449                 command = NULL;
 450
 451                 while (argc) {
 452                     while (*p) {
 453                         if (cmdlen >= cmdsize) {
 454                             cmdsize = cmdlen + 512;
 455                             command = sresize(command, cmdsize, char);
 456                         }
 457                         command[cmdlen++]=*p++;
 458                     }
 459                     if (cmdlen >= cmdsize) {
 460                         cmdsize = cmdlen + 512;
 461                         command = sresize(command, cmdsize, char);
 462                     }
 463                     command[cmdlen++]=' '; /* always add trailing space */
 464                     if (--argc) p = *++argv;
 465                 }
 466                 if (cmdlen) command[--cmdlen]='\0';
 467                                        /* change trailing blank to NUL */
 468                 conf_set_str(conf, CONF_remote_cmd, command);
 469                 conf_set_str(conf, CONF_remote_cmd2, "");
 470                 conf_set_int(conf, CONF_nopty, TRUE);  /* command => no tty */
 471
 472                 break;                 /* done with cmdline */
 473             }
 474         }
 475     }
 476
 477     if (errors)
 478         return 1;
 479
 480     if (!conf_launchable(conf) || !(got_host || loaded_session)) {
 481         usage();
 482     }
 483
 484     /*
 485      * Muck about with the hostname in various ways.
 486      */
 487     {
 488         char *hostbuf = dupstr(conf_get_str(conf, CONF_host));
 489         char *host = hostbuf;
 490         char *p, *q;
 491
 492         /*
 493          * Trim leading whitespace.
 494          */
 495         host += strspn(host, " \t");
 496
 497         /*
 498          * See if host is of the form user@host, and separate out
 499          * the username if so.
 500          */
 501         if (host[0] != '\0') {
 502             char *atsign = strrchr(host, '@');
 503             if (atsign) {
 504                 *atsign = '\0';
 505                 conf_set_str(conf, CONF_username, host);
 506                 host = atsign + 1;
 507             }
 508         }
 509
 510         /*
 511          * Trim off a colon suffix if it's there.
 512          */
 513         host[strcspn(host, ":")] = '\0';
 514
 515         /*
 516          * Remove any remaining whitespace.
 517          */
 518         p = hostbuf;
 519         q = host;
 520         while (*q) {
 521             if (*q != ' ' && *q != '\t')
 522                 *p++ = *q;
 523             q++;
 524         }
 525         *p = '\0';
 526
 527         conf_set_str(conf, CONF_host, hostbuf);
 528         sfree(hostbuf);
 529     }
 530
 531     /*
 532      * Perform command-line overrides on session configuration.
 533      */
 534     cmdline_run_saved(conf);
 535
 536     /*
 537      * Apply subsystem status.
 538      */
 539     if (use_subsystem)
 540         conf_set_int(conf, CONF_ssh_subsys, TRUE);
 541
 542     if (!*conf_get_str(conf, CONF_remote_cmd) &&
 543         !*conf_get_str(conf, CONF_remote_cmd2) &&
 544         !*conf_get_str(conf, CONF_ssh_nc_host))
 545         flags |= FLAG_INTERACTIVE;
 546
 547     /*
 548      * Select protocol. This is farmed out into a table in a
 549      * separate file to enable an ssh-free variant.
 550      */
 551     back = backend_from_proto(conf_get_int(conf, CONF_protocol));
 552     if (back == NULL) {
 553         fprintf(stderr,
 554                 "Internal fault: Unsupported protocol found\n");
 555         return 1;
 556     }
 557
 558     /*
 559      * Select port.
 560      */
 561     if (portnumber != -1)
 562         conf_set_int(conf, CONF_port, portnumber);
 563
 564     sk_init();
 565     if (p_WSAEventSelect == NULL) {
 566         fprintf(stderr, "Plink requires WinSock 2\n");
 567         return 1;
 568     }
 569
 570     logctx = log_init(NULL, conf);
 571     console_provide_logctx(logctx);
 572
 573     /*
 574      * Start up the connection.
 575      */
 576     netevent = CreateEvent(NULL, FALSE, FALSE, NULL);
 577     {
 578         const char *error;
 579         char *realhost;
 580         /* nodelay is only useful if stdin is a character device (console) */
 581         int nodelay = conf_get_int(conf, CONF_tcp_nodelay) &&
 582             (GetFileType(GetStdHandle(STD_INPUT_HANDLE)) == FILE_TYPE_CHAR);
 583
 584         error = back->init(NULL, &backhandle, conf,
 585                            conf_get_str(conf, CONF_host),
 586                            conf_get_int(conf, CONF_port),
 587                            &realhost, nodelay,
 588                            conf_get_int(conf, CONF_tcp_keepalives));
 589         if (error) {
 590             fprintf(stderr, "Unable to open connection:\n%s", error);
 591             return 1;
 592         }
 593         back->provide_logctx(backhandle, logctx);
 594         sfree(realhost);
 595     }
 596     connopen = 1;
 597
 598     inhandle = GetStdHandle(STD_INPUT_HANDLE);
 599     outhandle = GetStdHandle(STD_OUTPUT_HANDLE);
 600     errhandle = GetStdHandle(STD_ERROR_HANDLE);
 601
 602     /*
 603      * Turn off ECHO and LINE input modes. We don't care if this
 604      * call fails, because we know we aren't necessarily running in
 605      * a console.
 606      */
 607     GetConsoleMode(inhandle, &orig_console_mode);
 608     SetConsoleMode(inhandle, ENABLE_PROCESSED_INPUT);
 609
 610     /*
 611      * Pass the output handles to the handle-handling subsystem.
 612      * (The input one we leave until we're through the
 613      * authentication process.)
 614      */
 615     stdout_handle = handle_output_new(outhandle, stdouterr_sent, NULL, 0);
 616     stderr_handle = handle_output_new(errhandle, stdouterr_sent, NULL, 0);
 617
 618     main_thread_id = GetCurrentThreadId();
 619
 620     sending = FALSE;
 621
 622     now = GETTICKCOUNT();
 623
 624     while (1) {
 625         int nhandles;
 626         HANDLE *handles;
 627         int n;
 628         DWORD ticks;
 629
 630         if (!sending && back->sendok(backhandle)) {
 631             stdin_handle = handle_input_new(inhandle, stdin_gotdata, NULL,
 632                                             0);
 633             sending = TRUE;
 634         }
 635
 636         if (run_timers(now, &next)) {
 637         then = now;
 638         now = GETTICKCOUNT();
 639         if (now - then > next - then)
 640             ticks = 0;
 641         else
 642             ticks = next - now;
 643         } else {
 644             ticks = INFINITE;
 645         }
 646
 647         handles = handle_get_events(&nhandles);
 648         handles = sresize(handles, nhandles+1, HANDLE);
 649         handles[nhandles] = netevent;
 650         n = MsgWaitForMultipleObjects(nhandles+1, handles, FALSE, ticks,
 651                                       QS_POSTMESSAGE);
 652         if ((unsigned)(n - WAIT_OBJECT_0) < (unsigned)nhandles) {
 653             handle_got_event(handles[n - WAIT_OBJECT_0]);
 654         } else if (n == WAIT_OBJECT_0 + nhandles) {
 655             WSANETWORKEVENTS things;
 656             SOCKET socket;
 657             extern SOCKET first_socket(int *), next_socket(int *);
 658             extern int select_result(WPARAM, LPARAM);
 659             int i, socketstate;
 660
 661             /*
 662              * We must not call select_result() for any socket
 663              * until we have finished enumerating within the tree.
 664              * This is because select_result() may close the socket
 665              * and modify the tree.
 666              */
 667             /* Count the active sockets. */
 668             i = 0;
 669             for (socket = first_socket(&socketstate);
 670                  socket != INVALID_SOCKET;
 671                  socket = next_socket(&socketstate)) i++;
 672
 673             /* Expand the buffer if necessary. */
 674             if (i > sksize) {
 675                 sksize = i + 16;
 676                 sklist = sresize(sklist, sksize, SOCKET);
 677             }
 678
 679             /* Retrieve the sockets into sklist. */
 680             skcount = 0;
 681             for (socket = first_socket(&socketstate);
 682                  socket != INVALID_SOCKET;
 683                  socket = next_socket(&socketstate)) {
 684                 sklist[skcount++] = socket;
 685             }
 686
 687             /* Now we're done enumerating; go through the list. */
 688             for (i = 0; i < skcount; i++) {
 689                 WPARAM wp;
 690                 socket = sklist[i];
 691                 wp = (WPARAM) socket;
 692                 if (!p_WSAEnumNetworkEvents(socket, NULL, &things)) {
 693                     static const struct { int bit, mask; } eventtypes[] = {
 694                         {FD_CONNECT_BIT, FD_CONNECT},
 695                         {FD_READ_BIT, FD_READ},
 696                         {FD_CLOSE_BIT, FD_CLOSE},
 697                         {FD_OOB_BIT, FD_OOB},
 698                         {FD_WRITE_BIT, FD_WRITE},
 699                         {FD_ACCEPT_BIT, FD_ACCEPT},
 700                     };
 701                     int e;
 702
 703                     noise_ultralight(socket);
 704                     noise_ultralight(things.lNetworkEvents);
 705
 706                     for (e = 0; e < lenof(eventtypes); e++)
 707                         if (things.lNetworkEvents & eventtypes[e].mask) {
 708                             LPARAM lp;
 709                             int err = things.iErrorCode[eventtypes[e].bit];
 710                             lp = WSAMAKESELECTREPLY(eventtypes[e].mask, err);
 711                             connopen &= select_result(wp, lp);
 712                         }
 713                 }
 714             }
 715         } else if (n == WAIT_OBJECT_0 + nhandles + 1) {
 716             MSG msg;
 717             while (PeekMessage(&msg, INVALID_HANDLE_VALUE,
 718                                WM_AGENT_CALLBACK, WM_AGENT_CALLBACK,
 719                                PM_REMOVE)) {
 720                 struct agent_callback *c = (struct agent_callback *)msg.lParam;
 721                 c->callback(c->callback_ctx, c->data, c->len);
 722                 sfree(c);
 723             }
 724         }
 725
 726         if (n == WAIT_TIMEOUT) {
 727             now = next;
 728         } else {
 729             now = GETTICKCOUNT();
 730         }
 731
 732         sfree(handles);
 733
 734         if (sending)
 735             handle_unthrottle(stdin_handle, back->sendbuffer(backhandle));
 736
 737         if ((!connopen || !back->connected(backhandle)) &&
 738             handle_backlog(stdout_handle) + handle_backlog(stderr_handle) == 0)
 739             break;                     /* we closed the connection */
 740     }
 741     exitcode = back->exitcode(backhandle);
 742     if (exitcode < 0) {
 743         fprintf(stderr, "Remote process exit code unavailable\n");
 744         exitcode = 1;                  /* this is an error condition */
 745     }
 746     cleanup_exit(exitcode);
 747     return 0;                          /* placate compiler warning */
 748 }