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