git.distorted.org.uk Git - u/mdw/putty/blob - unix/uxplink.c

   1 /*
   2  * PLink - a command-line (stdin/stdout) variant of PuTTY.
   3  */
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <errno.h>
   8 #include <assert.h>
   9 #include <stdarg.h>
  10 #include <signal.h>
  11 #include <unistd.h>
  12 #include <fcntl.h>
  13 #include <termios.h>
  14 #include <pwd.h>
  15 #include <sys/ioctl.h>
  16 #include <sys/select.h>
  17
  18 #define PUTTY_DO_GLOBALS               /* actually _define_ globals */
  19 #include "putty.h"
  20 #include "storage.h"
  21 #include "tree234.h"
  22
  23 #define MAX_STDIN_BACKLOG 4096
  24
  25 void fatalbox(char *p, ...)
  26 {
  27     va_list ap;
  28     fprintf(stderr, "FATAL ERROR: ");
  29     va_start(ap, p);
  30     vfprintf(stderr, p, ap);
  31     va_end(ap);
  32     fputc('\n', stderr);
  33     cleanup_exit(1);
  34 }
  35 void modalfatalbox(char *p, ...)
  36 {
  37     va_list ap;
  38     fprintf(stderr, "FATAL ERROR: ");
  39     va_start(ap, p);
  40     vfprintf(stderr, p, ap);
  41     va_end(ap);
  42     fputc('\n', stderr);
  43     cleanup_exit(1);
  44 }
  45 void connection_fatal(void *frontend, char *p, ...)
  46 {
  47     va_list ap;
  48     fprintf(stderr, "FATAL ERROR: ");
  49     va_start(ap, p);
  50     vfprintf(stderr, p, ap);
  51     va_end(ap);
  52     fputc('\n', stderr);
  53     cleanup_exit(1);
  54 }
  55 void cmdline_error(char *p, ...)
  56 {
  57     va_list ap;
  58     fprintf(stderr, "plink: ");
  59     va_start(ap, p);
  60     vfprintf(stderr, p, ap);
  61     va_end(ap);
  62     fputc('\n', stderr);
  63     exit(1);
  64 }
  65
  66 struct termios orig_termios;
  67
  68 static Backend *back;
  69 static void *backhandle;
  70 static Config cfg;
  71
  72 /*
  73  * Default settings that are specific to pterm.
  74  */
  75 char *platform_default_s(const char *name)
  76 {
  77     if (!strcmp(name, "TermType"))
  78         return dupstr(getenv("TERM"));
  79     if (!strcmp(name, "UserName"))
  80         return get_username();
  81     return NULL;
  82 }
  83
  84 int platform_default_i(const char *name, int def)
  85 {
  86     if (!strcmp(name, "TermWidth") ||
  87         !strcmp(name, "TermHeight")) {
  88         struct winsize size;
  89         if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
  90             return (!strcmp(name, "TermWidth") ? size.ws_col : size.ws_row);
  91     }
  92     return def;
  93 }
  94
  95 FontSpec platform_default_fontspec(const char *name)
  96 {
  97     FontSpec ret;
  98     *ret.name = '\0';
  99     return ret;
 100 }
 101
 102 Filename platform_default_filename(const char *name)
 103 {
 104     Filename ret;
 105     if (!strcmp(name, "LogFileName"))
 106         strcpy(ret.path, "putty.log");
 107     else
 108         *ret.path = '\0';
 109     return ret;
 110 }
 111
 112 char *x_get_default(const char *key)
 113 {
 114     return NULL;                       /* this is a stub */
 115 }
 116 int term_ldisc(Terminal *term, int mode)
 117 {
 118     return FALSE;
 119 }
 120 void ldisc_update(void *frontend, int echo, int edit)
 121 {
 122     /* Update stdin read mode to reflect changes in line discipline. */
 123     struct termios mode;
 124
 125     mode = orig_termios;
 126
 127     if (echo)
 128         mode.c_lflag |= ECHO;
 129     else
 130         mode.c_lflag &= ~ECHO;
 131
 132     if (edit)
 133         mode.c_lflag |= ISIG | ICANON;
 134     else
 135         mode.c_lflag &= ~(ISIG | ICANON);
 136
 137     tcsetattr(0, TCSANOW, &mode);
 138 }
 139
 140 void cleanup_termios(void)
 141 {
 142     tcsetattr(0, TCSANOW, &orig_termios);
 143 }
 144
 145 bufchain stdout_data, stderr_data;
 146
 147 void try_output(int is_stderr)
 148 {
 149     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
 150     int fd = (is_stderr ? 2 : 1);
 151     void *senddata;
 152     int sendlen, ret;
 153
 154     if (bufchain_size(chain) == 0)
 155         return;
 156
 157     bufchain_prefix(chain, &senddata, &sendlen);
 158     ret = write(fd, senddata, sendlen);
 159     if (ret > 0)
 160         bufchain_consume(chain, ret);
 161     else if (ret < 0) {
 162         perror(is_stderr ? "stderr: write" : "stdout: write");
 163         exit(1);
 164     }
 165 }
 166
 167 int from_backend(void *frontend_handle, int is_stderr,
 168                  const char *data, int len)
 169 {
 170     int osize, esize;
 171
 172     if (is_stderr) {
 173         bufchain_add(&stderr_data, data, len);
 174         try_output(1);
 175     } else {
 176         bufchain_add(&stdout_data, data, len);
 177         try_output(0);
 178     }
 179
 180     osize = bufchain_size(&stdout_data);
 181     esize = bufchain_size(&stderr_data);
 182
 183     return osize + esize;
 184 }
 185
 186 int signalpipe[2];
 187
 188 void sigwinch(int signum)
 189 {
 190     write(signalpipe[1], "x", 1);
 191 }
 192
 193 /*
 194  * In Plink our selects are synchronous, so these functions are
 195  * empty stubs.
 196  */
 197 int uxsel_input_add(int fd, int rwx) { return 0; }
 198 void uxsel_input_remove(int id) { }
 199
 200 /*
 201  * Short description of parameters.
 202  */
 203 static void usage(void)
 204 {
 205     printf("PuTTY Link: command-line connection utility\n");
 206     printf("%s\n", ver);
 207     printf("Usage: plink [options] [user@]host [command]\n");
 208     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 209     printf("Options:\n");
 210     printf("  -V        print version information\n");
 211     printf("  -v        show verbose messages\n");
 212     printf("  -load sessname  Load settings from saved session\n");
 213     printf("  -ssh -telnet -rlogin -raw\n");
 214     printf("            force use of a particular protocol\n");
 215     printf("  -P port   connect to specified port\n");
 216     printf("  -l user   connect with specified username\n");
 217     printf("  -m file   read remote command(s) from file\n");
 218     printf("  -batch    disable all interactive prompts\n");
 219     printf("The following options only apply to SSH connections:\n");
 220     printf("  -pw passw login with specified password\n");
 221     printf("  -D [listen-IP:]listen-port\n");
 222     printf("            Dynamic SOCKS-based port forwarding\n");
 223     printf("  -L [listen-IP:]listen-port:host:port\n");
 224     printf("            Forward local port to remote address\n");
 225     printf("  -R [listen-IP:]listen-port:host:port\n");
 226     printf("            Forward remote port to local address\n");
 227     printf("  -X -x     enable / disable X11 forwarding\n");
 228     printf("  -A -a     enable / disable agent forwarding\n");
 229     printf("  -t -T     enable / disable pty allocation\n");
 230     printf("  -1 -2     force use of particular protocol version\n");
 231     printf("  -4 -6     force use of IPv4 or IPv6\n");
 232     printf("  -C        enable compression\n");
 233     printf("  -i key    private key file for authentication\n");
 234     printf("  -s        remote command is an SSH subsystem (SSH-2 only)\n");
 235     printf("  -N        don't start a shell/command (SSH-2 only)\n");
 236     exit(1);
 237 }
 238
 239 static void version(void)
 240 {
 241     printf("plink: %s\n", ver);
 242     exit(1);
 243 }
 244
 245 int main(int argc, char **argv)
 246 {
 247     int sending;
 248     int portnumber = -1;
 249     int *fdlist;
 250     int fd;
 251     int i, fdcount, fdsize, fdstate;
 252     int connopen;
 253     int exitcode;
 254     int errors;
 255     int use_subsystem = 0;
 256     void *ldisc, *logctx;
 257     long now;
 258
 259     ssh_get_line = console_get_line;
 260
 261     fdlist = NULL;
 262     fdcount = fdsize = 0;
 263     /*
 264      * Initialise port and protocol to sensible defaults. (These
 265      * will be overridden by more or less anything.)
 266      */
 267     default_protocol = PROT_SSH;
 268     default_port = 22;
 269
 270     flags = FLAG_STDERR;
 271     /*
 272      * Process the command line.
 273      */
 274     do_defaults(NULL, &cfg);
 275     loaded_session = FALSE;
 276     default_protocol = cfg.protocol;
 277     default_port = cfg.port;
 278     errors = 0;
 279     {
 280         /*
 281          * Override the default protocol if PLINK_PROTOCOL is set.
 282          */
 283         char *p = getenv("PLINK_PROTOCOL");
 284         int i;
 285         if (p) {
 286             for (i = 0; backends[i].backend != NULL; i++) {
 287                 if (!strcmp(backends[i].name, p)) {
 288                     default_protocol = cfg.protocol = backends[i].protocol;
 289                     default_port = cfg.port =
 290                         backends[i].backend->default_port;
 291                     break;
 292                 }
 293             }
 294         }
 295     }
 296     while (--argc) {
 297         char *p = *++argv;
 298         if (*p == '-') {
 299             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL),
 300                                             1, &cfg);
 301             if (ret == -2) {
 302                 fprintf(stderr,
 303                         "plink: option \"%s\" requires an argument\n", p);
 304                 errors = 1;
 305             } else if (ret == 2) {
 306                 --argc, ++argv;
 307             } else if (ret == 1) {
 308                 continue;
 309             } else if (!strcmp(p, "-batch")) {
 310                 console_batch_mode = 1;
 311             } else if (!strcmp(p, "-s")) {
 312                 /* Save status to write to cfg later. */
 313                 use_subsystem = 1;
 314             } else if (!strcmp(p, "-V")) {
 315                 version();
 316             } else if (!strcmp(p, "-o")) {
 317                 if (argc <= 1) {
 318                     fprintf(stderr,
 319                             "plink: option \"-o\" requires an argument\n");
 320                     errors = 1;
 321                 } else {
 322                     --argc;
 323                     provide_xrm_string(*++argv);
 324                 }
 325             } else {
 326                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 327                 errors = 1;
 328             }
 329         } else if (*p) {
 330             if (!*cfg.host) {
 331                 char *q = p;
 332
 333                 do_defaults(NULL, &cfg);
 334
 335                 /*
 336                  * If the hostname starts with "telnet:", set the
 337                  * protocol to Telnet and process the string as a
 338                  * Telnet URL.
 339                  */
 340                 if (!strncmp(q, "telnet:", 7)) {
 341                     char c;
 342
 343                     q += 7;
 344                     if (q[0] == '/' && q[1] == '/')
 345                         q += 2;
 346                     cfg.protocol = PROT_TELNET;
 347                     p = q;
 348                     while (*p && *p != ':' && *p != '/')
 349                         p++;
 350                     c = *p;
 351                     if (*p)
 352                         *p++ = '\0';
 353                     if (c == ':')
 354                         cfg.port = atoi(p);
 355                     else
 356                         cfg.port = -1;
 357                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 358                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 359                 } else {
 360                     char *r, *user, *host;
 361                     /*
 362                      * Before we process the [user@]host string, we
 363                      * first check for the presence of a protocol
 364                      * prefix (a protocol name followed by ",").
 365                      */
 366                     r = strchr(p, ',');
 367                     if (r) {
 368                         int i, j;
 369                         for (i = 0; backends[i].backend != NULL; i++) {
 370                             j = strlen(backends[i].name);
 371                             if (j == r - p &&
 372                                 !memcmp(backends[i].name, p, j)) {
 373                                 default_protocol = cfg.protocol =
 374                                     backends[i].protocol;
 375                                 portnumber =
 376                                     backends[i].backend->default_port;
 377                                 p = r + 1;
 378                                 break;
 379                             }
 380                         }
 381                     }
 382
 383                     /*
 384                      * A nonzero length string followed by an @ is treated
 385                      * as a username. (We discount an _initial_ @.) The
 386                      * rest of the string (or the whole string if no @)
 387                      * is treated as a session name and/or hostname.
 388                      */
 389                     r = strrchr(p, '@');
 390                     if (r == p)
 391                         p++, r = NULL; /* discount initial @ */
 392                     if (r) {
 393                         *r++ = '\0';
 394                         user = p, host = r;
 395                     } else {
 396                         user = NULL, host = p;
 397                     }
 398
 399                     /*
 400                      * Now attempt to load a saved session with the
 401                      * same name as the hostname.
 402                      */
 403                     {
 404                         Config cfg2;
 405                         do_defaults(host, &cfg2);
 406                         if (loaded_session || cfg2.host[0] == '\0') {
 407                             /* No settings for this host; use defaults */
 408                             /* (or session was already loaded with -load) */
 409                             strncpy(cfg.host, host, sizeof(cfg.host) - 1);
 410                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 411                             cfg.port = default_port;
 412                         } else {
 413                             cfg = cfg2;
 414                             /* Ick: patch up internal pointer after copy */
 415                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 416                         }
 417                     }
 418
 419                     if (user) {
 420                         /* Patch in specified username. */
 421                         strncpy(cfg.username, user,
 422                                 sizeof(cfg.username) - 1);
 423                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 424                     }
 425
 426                 }
 427             } else {
 428                 char *command;
 429                 int cmdlen, cmdsize;
 430                 cmdlen = cmdsize = 0;
 431                 command = NULL;
 432
 433                 while (argc) {
 434                     while (*p) {
 435                         if (cmdlen >= cmdsize) {
 436                             cmdsize = cmdlen + 512;
 437                             command = sresize(command, cmdsize, char);
 438                         }
 439                         command[cmdlen++]=*p++;
 440                     }
 441                     if (cmdlen >= cmdsize) {
 442                         cmdsize = cmdlen + 512;
 443                         command = sresize(command, cmdsize, char);
 444                     }
 445                     command[cmdlen++]=' '; /* always add trailing space */
 446                     if (--argc) p = *++argv;
 447                 }
 448                 if (cmdlen) command[--cmdlen]='\0';
 449                                        /* change trailing blank to NUL */
 450                 cfg.remote_cmd_ptr = command;
 451                 cfg.remote_cmd_ptr2 = NULL;
 452                 cfg.nopty = TRUE;      /* command => no terminal */
 453
 454                 break;                 /* done with cmdline */
 455             }
 456         }
 457     }
 458
 459     if (errors)
 460         return 1;
 461
 462     if (!*cfg.host) {
 463         usage();
 464     }
 465
 466     /*
 467      * Trim leading whitespace off the hostname if it's there.
 468      */
 469     {
 470         int space = strspn(cfg.host, " \t");
 471         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 472     }
 473
 474     /* See if host is of the form user@host */
 475     if (cfg.host[0] != '\0') {
 476         char *atsign = strrchr(cfg.host, '@');
 477         /* Make sure we're not overflowing the user field */
 478         if (atsign) {
 479             if (atsign - cfg.host < sizeof cfg.username) {
 480                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 481                 cfg.username[atsign - cfg.host] = '\0';
 482             }
 483             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 484         }
 485     }
 486
 487     /*
 488      * Perform command-line overrides on session configuration.
 489      */
 490     cmdline_run_saved(&cfg);
 491
 492     /*
 493      * Apply subsystem status.
 494      */
 495     if (use_subsystem)
 496         cfg.ssh_subsys = TRUE;
 497
 498     /*
 499      * Trim a colon suffix off the hostname if it's there.
 500      */
 501     cfg.host[strcspn(cfg.host, ":")] = '\0';
 502
 503     /*
 504      * Remove any remaining whitespace from the hostname.
 505      */
 506     {
 507         int p1 = 0, p2 = 0;
 508         while (cfg.host[p2] != '\0') {
 509             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 510                 cfg.host[p1] = cfg.host[p2];
 511                 p1++;
 512             }
 513             p2++;
 514         }
 515         cfg.host[p1] = '\0';
 516     }
 517
 518     if (!*cfg.remote_cmd_ptr)
 519         flags |= FLAG_INTERACTIVE;
 520
 521     /*
 522      * Select protocol. This is farmed out into a table in a
 523      * separate file to enable an ssh-free variant.
 524      */
 525     {
 526         int i;
 527         back = NULL;
 528         for (i = 0; backends[i].backend != NULL; i++)
 529             if (backends[i].protocol == cfg.protocol) {
 530                 back = backends[i].backend;
 531                 break;
 532             }
 533         if (back == NULL) {
 534             fprintf(stderr,
 535                     "Internal fault: Unsupported protocol found\n");
 536             return 1;
 537         }
 538     }
 539
 540     /*
 541      * Select port.
 542      */
 543     if (portnumber != -1)
 544         cfg.port = portnumber;
 545
 546     /*
 547      * Set up the pipe we'll use to tell us about SIGWINCH.
 548      */
 549     if (pipe(signalpipe) < 0) {
 550         perror("pipe");
 551         exit(1);
 552     }
 553     putty_signal(SIGWINCH, sigwinch);
 554
 555     sk_init();
 556     uxsel_init();
 557
 558     /*
 559      * Start up the connection.
 560      */
 561     logctx = log_init(NULL, &cfg);
 562     console_provide_logctx(logctx);
 563     {
 564         const char *error;
 565         char *realhost;
 566         /* nodelay is only useful if stdin is a terminal device */
 567         int nodelay = cfg.tcp_nodelay && isatty(0);
 568
 569         error = back->init(NULL, &backhandle, &cfg, cfg.host, cfg.port,
 570                            &realhost, nodelay, cfg.tcp_keepalives);
 571         if (error) {
 572             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 573             return 1;
 574         }
 575         back->provide_logctx(backhandle, logctx);
 576         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 577         sfree(realhost);
 578     }
 579     connopen = 1;
 580
 581     /*
 582      * Set up the initial console mode. We don't care if this call
 583      * fails, because we know we aren't necessarily running in a
 584      * console.
 585      */
 586     tcgetattr(0, &orig_termios);
 587     atexit(cleanup_termios);
 588     ldisc_update(NULL, 1, 1);
 589     sending = FALSE;
 590     now = GETTICKCOUNT();
 591
 592     while (1) {
 593         fd_set rset, wset, xset;
 594         int maxfd;
 595         int rwx;
 596         int ret;
 597
 598         FD_ZERO(&rset);
 599         FD_ZERO(&wset);
 600         FD_ZERO(&xset);
 601         maxfd = 0;
 602
 603         FD_SET_MAX(signalpipe[0], maxfd, rset);
 604
 605         if (connopen && !sending &&
 606             back->socket(backhandle) != NULL &&
 607             back->sendok(backhandle) &&
 608             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 609             /* If we're OK to send, then try to read from stdin. */
 610             FD_SET_MAX(0, maxfd, rset);
 611         }
 612
 613         if (bufchain_size(&stdout_data) > 0) {
 614             /* If we have data for stdout, try to write to stdout. */
 615             FD_SET_MAX(1, maxfd, wset);
 616         }
 617
 618         if (bufchain_size(&stderr_data) > 0) {
 619             /* If we have data for stderr, try to write to stderr. */
 620             FD_SET_MAX(2, maxfd, wset);
 621         }
 622
 623         /* Count the currently active fds. */
 624         i = 0;
 625         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 626              fd = next_fd(&fdstate, &rwx)) i++;
 627
 628         /* Expand the fdlist buffer if necessary. */
 629         if (i > fdsize) {
 630             fdsize = i + 16;
 631             fdlist = sresize(fdlist, fdsize, int);
 632         }
 633
 634         /*
 635          * Add all currently open fds to the select sets, and store
 636          * them in fdlist as well.
 637          */
 638         fdcount = 0;
 639         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 640              fd = next_fd(&fdstate, &rwx)) {
 641             fdlist[fdcount++] = fd;
 642             if (rwx & 1)
 643                 FD_SET_MAX(fd, maxfd, rset);
 644             if (rwx & 2)
 645                 FD_SET_MAX(fd, maxfd, wset);
 646             if (rwx & 4)
 647                 FD_SET_MAX(fd, maxfd, xset);
 648         }
 649
 650         do {
 651             long next, ticks;
 652             struct timeval tv, *ptv;
 653
 654             if (run_timers(now, &next)) {
 655                 ticks = next - GETTICKCOUNT();
 656                 if (ticks < 0) ticks = 0;   /* just in case */
 657                 tv.tv_sec = ticks / 1000;
 658                 tv.tv_usec = ticks % 1000 * 1000;
 659                 ptv = &tv;
 660             } else {
 661                 ptv = NULL;
 662             }
 663             ret = select(maxfd, &rset, &wset, &xset, ptv);
 664             if (ret == 0)
 665                 now = next;
 666             else
 667                 now = GETTICKCOUNT();
 668         } while (ret < 0 && errno == EINTR);
 669
 670         if (ret < 0) {
 671             perror("select");
 672             exit(1);
 673         }
 674
 675         for (i = 0; i < fdcount; i++) {
 676             fd = fdlist[i];
 677             /*
 678              * We must process exceptional notifications before
 679              * ordinary readability ones, or we may go straight
 680              * past the urgent marker.
 681              */
 682             if (FD_ISSET(fd, &xset))
 683                 select_result(fd, 4);
 684             if (FD_ISSET(fd, &rset))
 685                 select_result(fd, 1);
 686             if (FD_ISSET(fd, &wset))
 687                 select_result(fd, 2);
 688         }
 689
 690         if (FD_ISSET(signalpipe[0], &rset)) {
 691             char c[1];
 692             struct winsize size;
 693             read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
 694             if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
 695                 back->size(backhandle, size.ws_col, size.ws_row);
 696         }
 697
 698         if (FD_ISSET(0, &rset)) {
 699             char buf[4096];
 700             int ret;
 701
 702             if (connopen && back->socket(backhandle) != NULL) {
 703                 ret = read(0, buf, sizeof(buf));
 704                 if (ret < 0) {
 705                     perror("stdin: read");
 706                     exit(1);
 707                 } else if (ret == 0) {
 708                     back->special(backhandle, TS_EOF);
 709                     sending = FALSE;   /* send nothing further after this */
 710                 } else {
 711                     back->send(backhandle, buf, ret);
 712                 }
 713             }
 714         }
 715
 716         if (FD_ISSET(1, &wset)) {
 717             try_output(0);
 718         }
 719
 720         if (FD_ISSET(2, &wset)) {
 721             try_output(1);
 722         }
 723
 724         if ((!connopen || back->socket(backhandle) == NULL) &&
 725             bufchain_size(&stdout_data) == 0 &&
 726             bufchain_size(&stderr_data) == 0)
 727             break;                     /* we closed the connection */
 728     }
 729     exitcode = back->exitcode(backhandle);
 730     if (exitcode < 0) {
 731         fprintf(stderr, "Remote process exit code unavailable\n");
 732         exitcode = 1;                  /* this is an error condition */
 733     }
 734     cleanup_exit(exitcode);
 735     return exitcode;                   /* shouldn't happen, but placates gcc */
 736 }