mdw@git.distorted.org.uk Git - sgt/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
  17 #define PUTTY_DO_GLOBALS               /* actually _define_ globals */
  18 #include "putty.h"
  19 #include "storage.h"
  20 #include "tree234.h"
  21
  22 #define MAX_STDIN_BACKLOG 4096
  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     cleanup_exit(1);
  33 }
  34 void modalfatalbox(char *p, ...)
  35 {
  36     va_list ap;
  37     fprintf(stderr, "FATAL ERROR: ");
  38     va_start(ap, p);
  39     vfprintf(stderr, p, ap);
  40     va_end(ap);
  41     fputc('\n', stderr);
  42     cleanup_exit(1);
  43 }
  44 void connection_fatal(void *frontend, char *p, ...)
  45 {
  46     va_list ap;
  47     fprintf(stderr, "FATAL ERROR: ");
  48     va_start(ap, p);
  49     vfprintf(stderr, p, ap);
  50     va_end(ap);
  51     fputc('\n', stderr);
  52     cleanup_exit(1);
  53 }
  54 void cmdline_error(char *p, ...)
  55 {
  56     va_list ap;
  57     fprintf(stderr, "plink: ");
  58     va_start(ap, p);
  59     vfprintf(stderr, p, ap);
  60     va_end(ap);
  61     fputc('\n', stderr);
  62     exit(1);
  63 }
  64
  65 struct termios orig_termios;
  66
  67 static Backend *back;
  68 static void *backhandle;
  69 static Config cfg;
  70
  71 /*
  72  * Default settings that are specific to pterm.
  73  */
  74 char *platform_default_s(const char *name)
  75 {
  76     if (!strcmp(name, "X11Display"))
  77         return dupstr(getenv("DISPLAY"));
  78     if (!strcmp(name, "TermType"))
  79         return dupstr(getenv("TERM"));
  80     if (!strcmp(name, "UserName"))
  81         return get_username();
  82     return NULL;
  83 }
  84
  85 int platform_default_i(const char *name, int def)
  86 {
  87     if (!strcmp(name, "TermWidth") ||
  88         !strcmp(name, "TermHeight")) {
  89         struct winsize size;
  90         if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
  91             return (!strcmp(name, "TermWidth") ? size.ws_col : size.ws_row);
  92     }
  93     return def;
  94 }
  95
  96 FontSpec platform_default_fontspec(const char *name)
  97 {
  98     FontSpec ret;
  99     *ret.name = '\0';
 100     return ret;
 101 }
 102
 103 Filename platform_default_filename(const char *name)
 104 {
 105     Filename ret;
 106     if (!strcmp(name, "LogFileName"))
 107         strcpy(ret.path, "putty.log");
 108     else
 109         *ret.path = '\0';
 110     return ret;
 111 }
 112
 113 char *x_get_default(const char *key)
 114 {
 115     return NULL;                       /* this is a stub */
 116 }
 117 int term_ldisc(Terminal *term, int mode)
 118 {
 119     return FALSE;
 120 }
 121 void ldisc_update(void *frontend, int echo, int edit)
 122 {
 123     /* Update stdin read mode to reflect changes in line discipline. */
 124     struct termios mode;
 125
 126     mode = orig_termios;
 127
 128     if (echo)
 129         mode.c_lflag |= ECHO;
 130     else
 131         mode.c_lflag &= ~ECHO;
 132
 133     if (edit)
 134         mode.c_lflag |= ISIG | ICANON;
 135     else
 136         mode.c_lflag &= ~(ISIG | ICANON);
 137
 138     tcsetattr(0, TCSANOW, &mode);
 139 }
 140
 141 void cleanup_termios(void)
 142 {
 143     tcsetattr(0, TCSANOW, &orig_termios);
 144 }
 145
 146 bufchain stdout_data, stderr_data;
 147
 148 void try_output(int is_stderr)
 149 {
 150     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
 151     int fd = (is_stderr ? 2 : 1);
 152     void *senddata;
 153     int sendlen, ret;
 154
 155     if (bufchain_size(chain) == 0)
 156         return;
 157
 158     bufchain_prefix(chain, &senddata, &sendlen);
 159     ret = write(fd, senddata, sendlen);
 160     if (ret > 0)
 161         bufchain_consume(chain, ret);
 162     else if (ret < 0) {
 163         perror(is_stderr ? "stderr: write" : "stdout: write");
 164         exit(1);
 165     }
 166 }
 167
 168 int from_backend(void *frontend_handle, int is_stderr,
 169                  const char *data, int len)
 170 {
 171     int osize, esize;
 172
 173     if (is_stderr) {
 174         bufchain_add(&stderr_data, data, len);
 175         try_output(1);
 176     } else {
 177         bufchain_add(&stdout_data, data, len);
 178         try_output(0);
 179     }
 180
 181     osize = bufchain_size(&stdout_data);
 182     esize = bufchain_size(&stderr_data);
 183
 184     return osize + esize;
 185 }
 186
 187 int signalpipe[2];
 188
 189 void sigwinch(int signum)
 190 {
 191     write(signalpipe[1], "x", 1);
 192 }
 193
 194 /*
 195  * In Plink our selects are synchronous, so these functions are
 196  * empty stubs.
 197  */
 198 int uxsel_input_add(int fd, int rwx) { return 0; }
 199 void uxsel_input_remove(int id) { }
 200
 201 /*
 202  * Short description of parameters.
 203  */
 204 static void usage(void)
 205 {
 206     printf("PuTTY Link: command-line connection utility\n");
 207     printf("%s\n", ver);
 208     printf("Usage: plink [options] [user@]host [command]\n");
 209     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 210     printf("Options:\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 (default SSH)\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-port   Dynamic SOCKS-based port forwarding\n");
 222     printf("  -L listen-port:host:port   Forward local port to "
 223            "remote address\n");
 224     printf("  -R listen-port:host:port   Forward remote port to"
 225            " local address\n");
 226     printf("  -X -x     enable / disable X11 forwarding\n");
 227     printf("  -A -a     enable / disable agent forwarding\n");
 228     printf("  -t -T     enable / disable pty allocation\n");
 229     printf("  -1 -2     force use of particular protocol version\n");
 230     printf("  -C        enable compression\n");
 231     printf("  -i key    private key file for authentication\n");
 232     printf("  -s        remote command is an SSH subsystem (SSH-2 only)\n");
 233     exit(1);
 234 }
 235
 236 int main(int argc, char **argv)
 237 {
 238     int sending;
 239     int portnumber = -1;
 240     int *fdlist;
 241     int fd;
 242     int i, fdcount, fdsize, fdstate;
 243     int connopen;
 244     int exitcode;
 245     int errors;
 246     int use_subsystem = 0;
 247     void *ldisc, *logctx;
 248
 249     ssh_get_line = console_get_line;
 250
 251     fdlist = NULL;
 252     fdcount = fdsize = 0;
 253     /*
 254      * Initialise port and protocol to sensible defaults. (These
 255      * will be overridden by more or less anything.)
 256      */
 257     default_protocol = PROT_SSH;
 258     default_port = 22;
 259
 260     flags = FLAG_STDERR;
 261     /*
 262      * Process the command line.
 263      */
 264     do_defaults(NULL, &cfg);
 265     default_protocol = cfg.protocol;
 266     default_port = cfg.port;
 267     errors = 0;
 268     {
 269         /*
 270          * Override the default protocol if PLINK_PROTOCOL is set.
 271          */
 272         char *p = getenv("PLINK_PROTOCOL");
 273         int i;
 274         if (p) {
 275             for (i = 0; backends[i].backend != NULL; i++) {
 276                 if (!strcmp(backends[i].name, p)) {
 277                     default_protocol = cfg.protocol = backends[i].protocol;
 278                     default_port = cfg.port =
 279                         backends[i].backend->default_port;
 280                     break;
 281                 }
 282             }
 283         }
 284     }
 285     while (--argc) {
 286         char *p = *++argv;
 287         if (*p == '-') {
 288             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL),
 289                                             1, &cfg);
 290             if (ret == -2) {
 291                 fprintf(stderr,
 292                         "plink: option \"%s\" requires an argument\n", p);
 293                 errors = 1;
 294             } else if (ret == 2) {
 295                 --argc, ++argv;
 296             } else if (ret == 1) {
 297                 continue;
 298             } else if (!strcmp(p, "-batch")) {
 299                 console_batch_mode = 1;
 300             } else if (!strcmp(p, "-s")) {
 301                 /* Save status to write to cfg later. */
 302                 use_subsystem = 1;
 303             } else if (!strcmp(p, "-o")) {
 304                 if (argc <= 1) {
 305                     fprintf(stderr,
 306                             "plink: option \"-o\" requires an argument\n");
 307                     errors = 1;
 308                 } else {
 309                     --argc;
 310                     provide_xrm_string(*++argv);
 311                 }
 312             } else {
 313                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 314                 errors = 1;
 315             }
 316         } else if (*p) {
 317             if (!*cfg.host) {
 318                 char *q = p;
 319
 320                 do_defaults(NULL, &cfg);
 321
 322                 /*
 323                  * If the hostname starts with "telnet:", set the
 324                  * protocol to Telnet and process the string as a
 325                  * Telnet URL.
 326                  */
 327                 if (!strncmp(q, "telnet:", 7)) {
 328                     char c;
 329
 330                     q += 7;
 331                     if (q[0] == '/' && q[1] == '/')
 332                         q += 2;
 333                     cfg.protocol = PROT_TELNET;
 334                     p = q;
 335                     while (*p && *p != ':' && *p != '/')
 336                         p++;
 337                     c = *p;
 338                     if (*p)
 339                         *p++ = '\0';
 340                     if (c == ':')
 341                         cfg.port = atoi(p);
 342                     else
 343                         cfg.port = -1;
 344                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 345                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 346                 } else {
 347                     char *r;
 348                     /*
 349                      * Before we process the [user@]host string, we
 350                      * first check for the presence of a protocol
 351                      * prefix (a protocol name followed by ",").
 352                      */
 353                     r = strchr(p, ',');
 354                     if (r) {
 355                         int i, j;
 356                         for (i = 0; backends[i].backend != NULL; i++) {
 357                             j = strlen(backends[i].name);
 358                             if (j == r - p &&
 359                                 !memcmp(backends[i].name, p, j)) {
 360                                 default_protocol = cfg.protocol =
 361                                     backends[i].protocol;
 362                                 portnumber =
 363                                     backends[i].backend->default_port;
 364                                 p = r + 1;
 365                                 break;
 366                             }
 367                         }
 368                     }
 369
 370                     /*
 371                      * Three cases. Either (a) there's a nonzero
 372                      * length string followed by an @, in which
 373                      * case that's user and the remainder is host.
 374                      * Or (b) there's only one string, not counting
 375                      * a potential initial @, and it exists in the
 376                      * saved-sessions database. Or (c) only one
 377                      * string and it _doesn't_ exist in the
 378                      * database.
 379                      */
 380                     r = strrchr(p, '@');
 381                     if (r == p)
 382                         p++, r = NULL; /* discount initial @ */
 383                     if (r == NULL) {
 384                         /*
 385                          * One string.
 386                          */
 387                         Config cfg2;
 388                         do_defaults(p, &cfg2);
 389                         if (cfg2.host[0] == '\0') {
 390                             /* No settings for this host; use defaults */
 391                             strncpy(cfg.host, p, sizeof(cfg.host) - 1);
 392                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 393                             cfg.port = default_port;
 394                         } else {
 395                             cfg = cfg2;
 396                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 397                         }
 398                     } else {
 399                         *r++ = '\0';
 400                         strncpy(cfg.username, p, sizeof(cfg.username) - 1);
 401                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 402                         strncpy(cfg.host, r, sizeof(cfg.host) - 1);
 403                         cfg.host[sizeof(cfg.host) - 1] = '\0';
 404                         cfg.port = default_port;
 405                     }
 406                 }
 407             } else {
 408                 char *command;
 409                 int cmdlen, cmdsize;
 410                 cmdlen = cmdsize = 0;
 411                 command = NULL;
 412
 413                 while (argc) {
 414                     while (*p) {
 415                         if (cmdlen >= cmdsize) {
 416                             cmdsize = cmdlen + 512;
 417                             command = sresize(command, cmdsize, char);
 418                         }
 419                         command[cmdlen++]=*p++;
 420                     }
 421                     if (cmdlen >= cmdsize) {
 422                         cmdsize = cmdlen + 512;
 423                         command = sresize(command, cmdsize, char);
 424                     }
 425                     command[cmdlen++]=' '; /* always add trailing space */
 426                     if (--argc) p = *++argv;
 427                 }
 428                 if (cmdlen) command[--cmdlen]='\0';
 429                                        /* change trailing blank to NUL */
 430                 cfg.remote_cmd_ptr = command;
 431                 cfg.remote_cmd_ptr2 = NULL;
 432                 cfg.nopty = TRUE;      /* command => no terminal */
 433
 434                 break;                 /* done with cmdline */
 435             }
 436         }
 437     }
 438
 439     if (errors)
 440         return 1;
 441
 442     if (!*cfg.host) {
 443         usage();
 444     }
 445
 446     /*
 447      * Trim leading whitespace off the hostname if it's there.
 448      */
 449     {
 450         int space = strspn(cfg.host, " \t");
 451         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 452     }
 453
 454     /* See if host is of the form user@host */
 455     if (cfg.host[0] != '\0') {
 456         char *atsign = strchr(cfg.host, '@');
 457         /* Make sure we're not overflowing the user field */
 458         if (atsign) {
 459             if (atsign - cfg.host < sizeof cfg.username) {
 460                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 461                 cfg.username[atsign - cfg.host] = '\0';
 462             }
 463             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 464         }
 465     }
 466
 467     /*
 468      * Perform command-line overrides on session configuration.
 469      */
 470     cmdline_run_saved(&cfg);
 471
 472     /*
 473      * Apply subsystem status.
 474      */
 475     if (use_subsystem)
 476         cfg.ssh_subsys = TRUE;
 477
 478     /*
 479      * Trim a colon suffix off the hostname if it's there.
 480      */
 481     cfg.host[strcspn(cfg.host, ":")] = '\0';
 482
 483     /*
 484      * Remove any remaining whitespace from the hostname.
 485      */
 486     {
 487         int p1 = 0, p2 = 0;
 488         while (cfg.host[p2] != '\0') {
 489             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 490                 cfg.host[p1] = cfg.host[p2];
 491                 p1++;
 492             }
 493             p2++;
 494         }
 495         cfg.host[p1] = '\0';
 496     }
 497
 498     if (!*cfg.remote_cmd_ptr)
 499         flags |= FLAG_INTERACTIVE;
 500
 501     /*
 502      * Select protocol. This is farmed out into a table in a
 503      * separate file to enable an ssh-free variant.
 504      */
 505     {
 506         int i;
 507         back = NULL;
 508         for (i = 0; backends[i].backend != NULL; i++)
 509             if (backends[i].protocol == cfg.protocol) {
 510                 back = backends[i].backend;
 511                 break;
 512             }
 513         if (back == NULL) {
 514             fprintf(stderr,
 515                     "Internal fault: Unsupported protocol found\n");
 516             return 1;
 517         }
 518     }
 519
 520     /*
 521      * Select port.
 522      */
 523     if (portnumber != -1)
 524         cfg.port = portnumber;
 525
 526     /*
 527      * Set up the pipe we'll use to tell us about SIGWINCH.
 528      */
 529     if (pipe(signalpipe) < 0) {
 530         perror("pipe");
 531         exit(1);
 532     }
 533     putty_signal(SIGWINCH, sigwinch);
 534
 535     sk_init();
 536     uxsel_init();
 537
 538     /*
 539      * Start up the connection.
 540      */
 541     logctx = log_init(NULL, &cfg);
 542     console_provide_logctx(logctx);
 543     {
 544         const char *error;
 545         char *realhost;
 546         /* nodelay is only useful if stdin is a terminal device */
 547         int nodelay = cfg.tcp_nodelay && isatty(0);
 548
 549         error = back->init(NULL, &backhandle, &cfg, cfg.host, cfg.port,
 550                            &realhost, nodelay);
 551         if (error) {
 552             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 553             return 1;
 554         }
 555         back->provide_logctx(backhandle, logctx);
 556         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 557         sfree(realhost);
 558     }
 559     connopen = 1;
 560
 561     /*
 562      * Set up the initial console mode. We don't care if this call
 563      * fails, because we know we aren't necessarily running in a
 564      * console.
 565      */
 566     tcgetattr(0, &orig_termios);
 567     atexit(cleanup_termios);
 568     ldisc_update(NULL, 1, 1);
 569     sending = FALSE;
 570
 571     while (1) {
 572         fd_set rset, wset, xset;
 573         int maxfd;
 574         int rwx;
 575         int ret;
 576
 577         FD_ZERO(&rset);
 578         FD_ZERO(&wset);
 579         FD_ZERO(&xset);
 580         maxfd = 0;
 581
 582         FD_SET_MAX(signalpipe[0], maxfd, rset);
 583
 584         if (connopen && !sending &&
 585             back->socket(backhandle) != NULL &&
 586             back->sendok(backhandle) &&
 587             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 588             /* If we're OK to send, then try to read from stdin. */
 589             FD_SET_MAX(0, maxfd, rset);
 590         }
 591
 592         if (bufchain_size(&stdout_data) > 0) {
 593             /* If we have data for stdout, try to write to stdout. */
 594             FD_SET_MAX(1, maxfd, wset);
 595         }
 596
 597         if (bufchain_size(&stderr_data) > 0) {
 598             /* If we have data for stderr, try to write to stderr. */
 599             FD_SET_MAX(2, maxfd, wset);
 600         }
 601
 602         /* Count the currently active fds. */
 603         i = 0;
 604         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 605              fd = next_fd(&fdstate, &rwx)) i++;
 606
 607         /* Expand the fdlist buffer if necessary. */
 608         if (i > fdsize) {
 609             fdsize = i + 16;
 610             fdlist = sresize(fdlist, fdsize, int);
 611         }
 612
 613         /*
 614          * Add all currently open fds to the select sets, and store
 615          * them in fdlist as well.
 616          */
 617         fdcount = 0;
 618         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 619              fd = next_fd(&fdstate, &rwx)) {
 620             fdlist[fdcount++] = fd;
 621             if (rwx & 1)
 622                 FD_SET_MAX(fd, maxfd, rset);
 623             if (rwx & 2)
 624                 FD_SET_MAX(fd, maxfd, wset);
 625             if (rwx & 4)
 626                 FD_SET_MAX(fd, maxfd, xset);
 627         }
 628
 629         do {
 630             ret = select(maxfd, &rset, &wset, &xset, NULL);
 631         } while (ret < 0 && errno == EINTR);
 632
 633         if (ret < 0) {
 634             perror("select");
 635             exit(1);
 636         }
 637
 638         for (i = 0; i < fdcount; i++) {
 639             fd = fdlist[i];
 640             /*
 641              * We must process exceptional notifications before
 642              * ordinary readability ones, or we may go straight
 643              * past the urgent marker.
 644              */
 645             if (FD_ISSET(fd, &xset))
 646                 select_result(fd, 4);
 647             if (FD_ISSET(fd, &rset))
 648                 select_result(fd, 1);
 649             if (FD_ISSET(fd, &wset))
 650                 select_result(fd, 2);
 651         }
 652
 653         if (FD_ISSET(signalpipe[0], &rset)) {
 654             char c[1];
 655             struct winsize size;
 656             read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
 657             if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
 658                 back->size(backhandle, size.ws_col, size.ws_row);
 659         }
 660
 661         if (FD_ISSET(0, &rset)) {
 662             char buf[4096];
 663             int ret;
 664
 665             if (connopen && back->socket(backhandle) != NULL) {
 666                 ret = read(0, buf, sizeof(buf));
 667                 if (ret < 0) {
 668                     perror("stdin: read");
 669                     exit(1);
 670                 } else if (ret == 0) {
 671                     back->special(backhandle, TS_EOF);
 672                     sending = FALSE;   /* send nothing further after this */
 673                 } else {
 674                     back->send(backhandle, buf, ret);
 675                 }
 676             }
 677         }
 678
 679         if (FD_ISSET(1, &wset)) {
 680             try_output(0);
 681         }
 682
 683         if (FD_ISSET(2, &wset)) {
 684             try_output(1);
 685         }
 686
 687         if ((!connopen || back->socket(backhandle) == NULL) &&
 688             bufchain_size(&stdout_data) == 0 &&
 689             bufchain_size(&stderr_data) == 0)
 690             break;                     /* we closed the connection */
 691     }
 692     exitcode = back->exitcode(backhandle);
 693     if (exitcode < 0) {
 694         fprintf(stderr, "Remote process exit code unavailable\n");
 695         exitcode = 1;                  /* this is an error condition */
 696     }
 697     cleanup_exit(exitcode);
 698     return exitcode;                   /* shouldn't happen, but placates gcc */
 699 }