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_iflag |= ICRNL;
 134         mode.c_lflag |= ISIG | ICANON;
 135     } else {
 136         mode.c_iflag &= ~ICRNL;
 137         mode.c_lflag &= ~(ISIG | ICANON);
 138     }
 139
 140     tcsetattr(0, TCSANOW, &mode);
 141 }
 142
 143 void cleanup_termios(void)
 144 {
 145     tcsetattr(0, TCSANOW, &orig_termios);
 146 }
 147
 148 bufchain stdout_data, stderr_data;
 149
 150 void try_output(int is_stderr)
 151 {
 152     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
 153     int fd = (is_stderr ? 2 : 1);
 154     void *senddata;
 155     int sendlen, ret;
 156
 157     if (bufchain_size(chain) == 0)
 158         return;
 159
 160     bufchain_prefix(chain, &senddata, &sendlen);
 161     ret = write(fd, senddata, sendlen);
 162     if (ret > 0)
 163         bufchain_consume(chain, ret);
 164     else if (ret < 0) {
 165         perror(is_stderr ? "stderr: write" : "stdout: write");
 166         exit(1);
 167     }
 168 }
 169
 170 int from_backend(void *frontend_handle, int is_stderr,
 171                  const char *data, int len)
 172 {
 173     int osize, esize;
 174
 175     if (is_stderr) {
 176         bufchain_add(&stderr_data, data, len);
 177         try_output(1);
 178     } else {
 179         bufchain_add(&stdout_data, data, len);
 180         try_output(0);
 181     }
 182
 183     osize = bufchain_size(&stdout_data);
 184     esize = bufchain_size(&stderr_data);
 185
 186     return osize + esize;
 187 }
 188
 189 int signalpipe[2];
 190
 191 void sigwinch(int signum)
 192 {
 193     write(signalpipe[1], "x", 1);
 194 }
 195
 196 /*
 197  * In Plink our selects are synchronous, so these functions are
 198  * empty stubs.
 199  */
 200 int uxsel_input_add(int fd, int rwx) { return 0; }
 201 void uxsel_input_remove(int id) { }
 202
 203 /*
 204  * Short description of parameters.
 205  */
 206 static void usage(void)
 207 {
 208     printf("PuTTY Link: command-line connection utility\n");
 209     printf("%s\n", ver);
 210     printf("Usage: plink [options] [user@]host [command]\n");
 211     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 212     printf("Options:\n");
 213     printf("  -V        print version information\n");
 214     printf("  -v        show verbose messages\n");
 215     printf("  -load sessname  Load settings from saved session\n");
 216     printf("  -ssh -telnet -rlogin -raw\n");
 217     printf("            force use of a particular protocol\n");
 218     printf("  -P port   connect to specified port\n");
 219     printf("  -l user   connect with specified username\n");
 220     printf("  -batch    disable all interactive prompts\n");
 221     printf("The following options only apply to SSH connections:\n");
 222     printf("  -pw passw login with specified password\n");
 223     printf("  -D [listen-IP:]listen-port\n");
 224     printf("            Dynamic SOCKS-based port forwarding\n");
 225     printf("  -L [listen-IP:]listen-port:host:port\n");
 226     printf("            Forward local port to remote address\n");
 227     printf("  -R [listen-IP:]listen-port:host:port\n");
 228     printf("            Forward remote port to local address\n");
 229     printf("  -X -x     enable / disable X11 forwarding\n");
 230     printf("  -A -a     enable / disable agent forwarding\n");
 231     printf("  -t -T     enable / disable pty allocation\n");
 232     printf("  -1 -2     force use of particular protocol version\n");
 233     printf("  -4 -6     force use of IPv4 or IPv6\n");
 234     printf("  -C        enable compression\n");
 235     printf("  -i key    private key file for authentication\n");
 236     printf("  -m file   read remote command(s) from file\n");
 237     printf("  -s        remote command is an SSH subsystem (SSH-2 only)\n");
 238     printf("  -N        don't start a shell/command (SSH-2 only)\n");
 239     exit(1);
 240 }
 241
 242 static void version(void)
 243 {
 244     printf("plink: %s\n", ver);
 245     exit(1);
 246 }
 247
 248 int main(int argc, char **argv)
 249 {
 250     int sending;
 251     int portnumber = -1;
 252     int *fdlist;
 253     int fd;
 254     int i, fdcount, fdsize, fdstate;
 255     int connopen;
 256     int exitcode;
 257     int errors;
 258     int use_subsystem = 0;
 259     void *ldisc, *logctx;
 260     long now;
 261
 262     ssh_get_line = console_get_line;
 263
 264     fdlist = NULL;
 265     fdcount = fdsize = 0;
 266     /*
 267      * Initialise port and protocol to sensible defaults. (These
 268      * will be overridden by more or less anything.)
 269      */
 270     default_protocol = PROT_SSH;
 271     default_port = 22;
 272
 273     flags = FLAG_STDERR;
 274     /*
 275      * Process the command line.
 276      */
 277     do_defaults(NULL, &cfg);
 278     loaded_session = FALSE;
 279     default_protocol = cfg.protocol;
 280     default_port = cfg.port;
 281     errors = 0;
 282     {
 283         /*
 284          * Override the default protocol if PLINK_PROTOCOL is set.
 285          */
 286         char *p = getenv("PLINK_PROTOCOL");
 287         int i;
 288         if (p) {
 289             for (i = 0; backends[i].backend != NULL; i++) {
 290                 if (!strcmp(backends[i].name, p)) {
 291                     default_protocol = cfg.protocol = backends[i].protocol;
 292                     default_port = cfg.port =
 293                         backends[i].backend->default_port;
 294                     break;
 295                 }
 296             }
 297         }
 298     }
 299     while (--argc) {
 300         char *p = *++argv;
 301         if (*p == '-') {
 302             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL),
 303                                             1, &cfg);
 304             if (ret == -2) {
 305                 fprintf(stderr,
 306                         "plink: option \"%s\" requires an argument\n", p);
 307                 errors = 1;
 308             } else if (ret == 2) {
 309                 --argc, ++argv;
 310             } else if (ret == 1) {
 311                 continue;
 312             } else if (!strcmp(p, "-batch")) {
 313                 console_batch_mode = 1;
 314             } else if (!strcmp(p, "-s")) {
 315                 /* Save status to write to cfg later. */
 316                 use_subsystem = 1;
 317             } else if (!strcmp(p, "-V")) {
 318                 version();
 319             } else if (!strcmp(p, "-o")) {
 320                 if (argc <= 1) {
 321                     fprintf(stderr,
 322                             "plink: option \"-o\" requires an argument\n");
 323                     errors = 1;
 324                 } else {
 325                     --argc;
 326                     provide_xrm_string(*++argv);
 327                 }
 328             } else {
 329                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 330                 errors = 1;
 331             }
 332         } else if (*p) {
 333             if (!*cfg.host) {
 334                 char *q = p;
 335
 336                 do_defaults(NULL, &cfg);
 337
 338                 /*
 339                  * If the hostname starts with "telnet:", set the
 340                  * protocol to Telnet and process the string as a
 341                  * Telnet URL.
 342                  */
 343                 if (!strncmp(q, "telnet:", 7)) {
 344                     char c;
 345
 346                     q += 7;
 347                     if (q[0] == '/' && q[1] == '/')
 348                         q += 2;
 349                     cfg.protocol = PROT_TELNET;
 350                     p = q;
 351                     while (*p && *p != ':' && *p != '/')
 352                         p++;
 353                     c = *p;
 354                     if (*p)
 355                         *p++ = '\0';
 356                     if (c == ':')
 357                         cfg.port = atoi(p);
 358                     else
 359                         cfg.port = -1;
 360                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 361                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 362                 } else {
 363                     char *r, *user, *host;
 364                     /*
 365                      * Before we process the [user@]host string, we
 366                      * first check for the presence of a protocol
 367                      * prefix (a protocol name followed by ",").
 368                      */
 369                     r = strchr(p, ',');
 370                     if (r) {
 371                         int i, j;
 372                         for (i = 0; backends[i].backend != NULL; i++) {
 373                             j = strlen(backends[i].name);
 374                             if (j == r - p &&
 375                                 !memcmp(backends[i].name, p, j)) {
 376                                 default_protocol = cfg.protocol =
 377                                     backends[i].protocol;
 378                                 portnumber =
 379                                     backends[i].backend->default_port;
 380                                 p = r + 1;
 381                                 break;
 382                             }
 383                         }
 384                     }
 385
 386                     /*
 387                      * A nonzero length string followed by an @ is treated
 388                      * as a username. (We discount an _initial_ @.) The
 389                      * rest of the string (or the whole string if no @)
 390                      * is treated as a session name and/or hostname.
 391                      */
 392                     r = strrchr(p, '@');
 393                     if (r == p)
 394                         p++, r = NULL; /* discount initial @ */
 395                     if (r) {
 396                         *r++ = '\0';
 397                         user = p, host = r;
 398                     } else {
 399                         user = NULL, host = p;
 400                     }
 401
 402                     /*
 403                      * Now attempt to load a saved session with the
 404                      * same name as the hostname.
 405                      */
 406                     {
 407                         Config cfg2;
 408                         do_defaults(host, &cfg2);
 409                         if (loaded_session || cfg2.host[0] == '\0') {
 410                             /* No settings for this host; use defaults */
 411                             /* (or session was already loaded with -load) */
 412                             strncpy(cfg.host, host, sizeof(cfg.host) - 1);
 413                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 414                             cfg.port = default_port;
 415                         } else {
 416                             cfg = cfg2;
 417                         }
 418                     }
 419
 420                     if (user) {
 421                         /* Patch in specified username. */
 422                         strncpy(cfg.username, user,
 423                                 sizeof(cfg.username) - 1);
 424                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 425                     }
 426
 427                 }
 428             } else {
 429                 char *command;
 430                 int cmdlen, cmdsize;
 431                 cmdlen = cmdsize = 0;
 432                 command = NULL;
 433
 434                 while (argc) {
 435                     while (*p) {
 436                         if (cmdlen >= cmdsize) {
 437                             cmdsize = cmdlen + 512;
 438                             command = sresize(command, cmdsize, char);
 439                         }
 440                         command[cmdlen++]=*p++;
 441                     }
 442                     if (cmdlen >= cmdsize) {
 443                         cmdsize = cmdlen + 512;
 444                         command = sresize(command, cmdsize, char);
 445                     }
 446                     command[cmdlen++]=' '; /* always add trailing space */
 447                     if (--argc) p = *++argv;
 448                 }
 449                 if (cmdlen) command[--cmdlen]='\0';
 450                                        /* change trailing blank to NUL */
 451                 cfg.remote_cmd_ptr = command;
 452                 cfg.remote_cmd_ptr2 = NULL;
 453                 cfg.nopty = TRUE;      /* command => no terminal */
 454
 455                 break;                 /* done with cmdline */
 456             }
 457         }
 458     }
 459
 460     if (errors)
 461         return 1;
 462
 463     if (!*cfg.host) {
 464         usage();
 465     }
 466
 467     /*
 468      * Trim leading whitespace off the hostname if it's there.
 469      */
 470     {
 471         int space = strspn(cfg.host, " \t");
 472         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 473     }
 474
 475     /* See if host is of the form user@host */
 476     if (cfg.host[0] != '\0') {
 477         char *atsign = strrchr(cfg.host, '@');
 478         /* Make sure we're not overflowing the user field */
 479         if (atsign) {
 480             if (atsign - cfg.host < sizeof cfg.username) {
 481                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 482                 cfg.username[atsign - cfg.host] = '\0';
 483             }
 484             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 485         }
 486     }
 487
 488     /*
 489      * Perform command-line overrides on session configuration.
 490      */
 491     cmdline_run_saved(&cfg);
 492
 493     /*
 494      * Apply subsystem status.
 495      */
 496     if (use_subsystem)
 497         cfg.ssh_subsys = TRUE;
 498
 499     /*
 500      * Trim a colon suffix off the hostname if it's there.
 501      */
 502     cfg.host[strcspn(cfg.host, ":")] = '\0';
 503
 504     /*
 505      * Remove any remaining whitespace from the hostname.
 506      */
 507     {
 508         int p1 = 0, p2 = 0;
 509         while (cfg.host[p2] != '\0') {
 510             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 511                 cfg.host[p1] = cfg.host[p2];
 512                 p1++;
 513             }
 514             p2++;
 515         }
 516         cfg.host[p1] = '\0';
 517     }
 518
 519     if (!cfg.remote_cmd_ptr && !*cfg.remote_cmd)
 520         flags |= FLAG_INTERACTIVE;
 521
 522     /*
 523      * Select protocol. This is farmed out into a table in a
 524      * separate file to enable an ssh-free variant.
 525      */
 526     {
 527         int i;
 528         back = NULL;
 529         for (i = 0; backends[i].backend != NULL; i++)
 530             if (backends[i].protocol == cfg.protocol) {
 531                 back = backends[i].backend;
 532                 break;
 533             }
 534         if (back == NULL) {
 535             fprintf(stderr,
 536                     "Internal fault: Unsupported protocol found\n");
 537             return 1;
 538         }
 539     }
 540
 541     /*
 542      * Select port.
 543      */
 544     if (portnumber != -1)
 545         cfg.port = portnumber;
 546
 547     /*
 548      * Set up the pipe we'll use to tell us about SIGWINCH.
 549      */
 550     if (pipe(signalpipe) < 0) {
 551         perror("pipe");
 552         exit(1);
 553     }
 554     putty_signal(SIGWINCH, sigwinch);
 555
 556     sk_init();
 557     uxsel_init();
 558
 559     /*
 560      * Start up the connection.
 561      */
 562     logctx = log_init(NULL, &cfg);
 563     console_provide_logctx(logctx);
 564     {
 565         const char *error;
 566         char *realhost;
 567         /* nodelay is only useful if stdin is a terminal device */
 568         int nodelay = cfg.tcp_nodelay && isatty(0);
 569
 570         error = back->init(NULL, &backhandle, &cfg, cfg.host, cfg.port,
 571                            &realhost, nodelay, cfg.tcp_keepalives);
 572         if (error) {
 573             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 574             return 1;
 575         }
 576         back->provide_logctx(backhandle, logctx);
 577         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 578         sfree(realhost);
 579     }
 580     connopen = 1;
 581
 582     /*
 583      * Set up the initial console mode. We don't care if this call
 584      * fails, because we know we aren't necessarily running in a
 585      * console.
 586      */
 587     tcgetattr(0, &orig_termios);
 588     atexit(cleanup_termios);
 589     ldisc_update(NULL, 1, 1);
 590     sending = FALSE;
 591     now = GETTICKCOUNT();
 592
 593     while (1) {
 594         fd_set rset, wset, xset;
 595         int maxfd;
 596         int rwx;
 597         int ret;
 598
 599         FD_ZERO(&rset);
 600         FD_ZERO(&wset);
 601         FD_ZERO(&xset);
 602         maxfd = 0;
 603
 604         FD_SET_MAX(signalpipe[0], maxfd, rset);
 605
 606         if (connopen && !sending &&
 607             back->socket(backhandle) != NULL &&
 608             back->sendok(backhandle) &&
 609             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 610             /* If we're OK to send, then try to read from stdin. */
 611             FD_SET_MAX(0, maxfd, rset);
 612         }
 613
 614         if (bufchain_size(&stdout_data) > 0) {
 615             /* If we have data for stdout, try to write to stdout. */
 616             FD_SET_MAX(1, maxfd, wset);
 617         }
 618
 619         if (bufchain_size(&stderr_data) > 0) {
 620             /* If we have data for stderr, try to write to stderr. */
 621             FD_SET_MAX(2, maxfd, wset);
 622         }
 623
 624         /* Count the currently active fds. */
 625         i = 0;
 626         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 627              fd = next_fd(&fdstate, &rwx)) i++;
 628
 629         /* Expand the fdlist buffer if necessary. */
 630         if (i > fdsize) {
 631             fdsize = i + 16;
 632             fdlist = sresize(fdlist, fdsize, int);
 633         }
 634
 635         /*
 636          * Add all currently open fds to the select sets, and store
 637          * them in fdlist as well.
 638          */
 639         fdcount = 0;
 640         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 641              fd = next_fd(&fdstate, &rwx)) {
 642             fdlist[fdcount++] = fd;
 643             if (rwx & 1)
 644                 FD_SET_MAX(fd, maxfd, rset);
 645             if (rwx & 2)
 646                 FD_SET_MAX(fd, maxfd, wset);
 647             if (rwx & 4)
 648                 FD_SET_MAX(fd, maxfd, xset);
 649         }
 650
 651         do {
 652             long next, ticks;
 653             struct timeval tv, *ptv;
 654
 655             if (run_timers(now, &next)) {
 656                 ticks = next - GETTICKCOUNT();
 657                 if (ticks < 0) ticks = 0;   /* just in case */
 658                 tv.tv_sec = ticks / 1000;
 659                 tv.tv_usec = ticks % 1000 * 1000;
 660                 ptv = &tv;
 661             } else {
 662                 ptv = NULL;
 663             }
 664             ret = select(maxfd, &rset, &wset, &xset, ptv);
 665             if (ret == 0)
 666                 now = next;
 667             else
 668                 now = GETTICKCOUNT();
 669         } while (ret < 0 && errno == EINTR);
 670
 671         if (ret < 0) {
 672             perror("select");
 673             exit(1);
 674         }
 675
 676         for (i = 0; i < fdcount; i++) {
 677             fd = fdlist[i];
 678             /*
 679              * We must process exceptional notifications before
 680              * ordinary readability ones, or we may go straight
 681              * past the urgent marker.
 682              */
 683             if (FD_ISSET(fd, &xset))
 684                 select_result(fd, 4);
 685             if (FD_ISSET(fd, &rset))
 686                 select_result(fd, 1);
 687             if (FD_ISSET(fd, &wset))
 688                 select_result(fd, 2);
 689         }
 690
 691         if (FD_ISSET(signalpipe[0], &rset)) {
 692             char c[1];
 693             struct winsize size;
 694             read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
 695             if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
 696                 back->size(backhandle, size.ws_col, size.ws_row);
 697         }
 698
 699         if (FD_ISSET(0, &rset)) {
 700             char buf[4096];
 701             int ret;
 702
 703             if (connopen && back->socket(backhandle) != NULL) {
 704                 ret = read(0, buf, sizeof(buf));
 705                 if (ret < 0) {
 706                     perror("stdin: read");
 707                     exit(1);
 708                 } else if (ret == 0) {
 709                     back->special(backhandle, TS_EOF);
 710                     sending = FALSE;   /* send nothing further after this */
 711                 } else {
 712                     back->send(backhandle, buf, ret);
 713                 }
 714             }
 715         }
 716
 717         if (FD_ISSET(1, &wset)) {
 718             try_output(0);
 719         }
 720
 721         if (FD_ISSET(2, &wset)) {
 722             try_output(1);
 723         }
 724
 725         if ((!connopen || back->socket(backhandle) == NULL) &&
 726             bufchain_size(&stdout_data) == 0 &&
 727             bufchain_size(&stderr_data) == 0)
 728             break;                     /* we closed the connection */
 729     }
 730     exitcode = back->exitcode(backhandle);
 731     if (exitcode < 0) {
 732         fprintf(stderr, "Remote process exit code unavailable\n");
 733         exitcode = 1;                  /* this is an error condition */
 734     }
 735     cleanup_exit(exitcode);
 736     return exitcode;                   /* shouldn't happen, but placates gcc */
 737 }