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 <assert.h>
   8 #include <stdarg.h>
   9 #include <unistd.h>
  10 #include <fcntl.h>
  11 #include <termios.h>
  12
  13 /* More helpful version of the FD_SET macro, to also handle maxfd. */
  14 #define FD_SET_MAX(fd, max, set) do { \
  15     FD_SET(fd, &set); \
  16     if (max < fd + 1) max = fd + 1; \
  17 } while (0)
  18
  19 #define PUTTY_DO_GLOBALS               /* actually _define_ globals */
  20 #include "putty.h"
  21 #include "storage.h"
  22 #include "tree234.h"
  23
  24 #define MAX_STDIN_BACKLOG 4096
  25
  26 void fatalbox(char *p, ...)
  27 {
  28     va_list ap;
  29     fprintf(stderr, "FATAL ERROR: ");
  30     va_start(ap, p);
  31     vfprintf(stderr, p, ap);
  32     va_end(ap);
  33     fputc('\n', stderr);
  34     cleanup_exit(1);
  35 }
  36 void modalfatalbox(char *p, ...)
  37 {
  38     va_list ap;
  39     fprintf(stderr, "FATAL ERROR: ");
  40     va_start(ap, p);
  41     vfprintf(stderr, p, ap);
  42     va_end(ap);
  43     fputc('\n', stderr);
  44     cleanup_exit(1);
  45 }
  46 void connection_fatal(void *frontend, char *p, ...)
  47 {
  48     va_list ap;
  49     fprintf(stderr, "FATAL ERROR: ");
  50     va_start(ap, p);
  51     vfprintf(stderr, p, ap);
  52     va_end(ap);
  53     fputc('\n', stderr);
  54     cleanup_exit(1);
  55 }
  56 void cmdline_error(char *p, ...)
  57 {
  58     va_list ap;
  59     fprintf(stderr, "plink: ");
  60     va_start(ap, p);
  61     vfprintf(stderr, p, ap);
  62     va_end(ap);
  63     fputc('\n', stderr);
  64     exit(1);
  65 }
  66
  67 struct termios orig_termios;
  68
  69 static Backend *back;
  70 static void *backhandle;
  71
  72 char *x_get_default(char *key)
  73 {
  74     return NULL;                       /* this is a stub */
  75 }
  76 int term_ldisc(Terminal *term, int mode)
  77 {
  78     return FALSE;
  79 }
  80 void ldisc_update(void *frontend, int echo, int edit)
  81 {
  82     /* Update stdin read mode to reflect changes in line discipline. */
  83     struct termios mode;
  84
  85     mode = orig_termios;
  86
  87     if (echo)
  88         mode.c_lflag |= ECHO;
  89     else
  90         mode.c_lflag &= ~ECHO;
  91
  92     if (edit)
  93         mode.c_lflag |= ISIG | ICANON;
  94     else
  95         mode.c_lflag &= ~(ISIG | ICANON);
  96
  97     tcsetattr(0, TCSANOW, &mode);
  98 }
  99
 100 void cleanup_termios(void)
 101 {
 102     tcsetattr(0, TCSANOW, &orig_termios);
 103 }
 104
 105 bufchain stdout_data, stderr_data;
 106
 107 void try_output(int is_stderr)
 108 {
 109     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
 110     int fd = (is_stderr ? 2 : 1);
 111     void *senddata;
 112     int sendlen, ret;
 113
 114     if (bufchain_size(chain) == 0)
 115         return;
 116
 117     bufchain_prefix(chain, &senddata, &sendlen);
 118     ret = write(fd, senddata, sendlen);
 119     if (ret > 0)
 120         bufchain_consume(chain, ret);
 121     else if (ret < 0) {
 122         perror(is_stderr ? "stderr: write" : "stdout: write");
 123         exit(1);
 124     }
 125 }
 126
 127 int from_backend(void *frontend_handle, int is_stderr, char *data, int len)
 128 {
 129     int osize, esize;
 130
 131     assert(len > 0);
 132
 133     if (is_stderr) {
 134         bufchain_add(&stderr_data, data, len);
 135         try_output(1);
 136     } else {
 137         bufchain_add(&stdout_data, data, len);
 138         try_output(0);
 139     }
 140
 141     osize = bufchain_size(&stdout_data);
 142     esize = bufchain_size(&stderr_data);
 143
 144     return osize + esize;
 145 }
 146
 147 /*
 148  * Short description of parameters.
 149  */
 150 static void usage(void)
 151 {
 152     printf("PuTTY Link: command-line connection utility\n");
 153     printf("%s\n", ver);
 154     printf("Usage: plink [options] [user@]host [command]\n");
 155     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 156     printf("Options:\n");
 157     printf("  -v        show verbose messages\n");
 158     printf("  -load sessname  Load settings from saved session\n");
 159     printf("  -ssh -telnet -rlogin -raw\n");
 160     printf("            force use of a particular protocol (default SSH)\n");
 161     printf("  -P port   connect to specified port\n");
 162     printf("  -l user   connect with specified username\n");
 163     printf("  -m file   read remote command(s) from file\n");
 164     printf("  -batch    disable all interactive prompts\n");
 165     printf("The following options only apply to SSH connections:\n");
 166     printf("  -pw passw login with specified password\n");
 167     printf("  -L listen-port:host:port   Forward local port to "
 168            "remote address\n");
 169     printf("  -R listen-port:host:port   Forward remote port to"
 170            " local address\n");
 171     printf("  -X -x     enable / disable X11 forwarding\n");
 172     printf("  -A -a     enable / disable agent forwarding\n");
 173     printf("  -t -T     enable / disable pty allocation\n");
 174     printf("  -1 -2     force use of particular protocol version\n");
 175     printf("  -C        enable compression\n");
 176     printf("  -i key    private key file for authentication\n");
 177     exit(1);
 178 }
 179
 180 int main(int argc, char **argv)
 181 {
 182     int sending;
 183     int portnumber = -1;
 184     int *sklist;
 185     int socket;
 186     int i, skcount, sksize, socketstate;
 187     int connopen;
 188     int exitcode;
 189     int errors;
 190     void *ldisc;
 191
 192     ssh_get_line = console_get_line;
 193
 194     sklist = NULL;
 195     skcount = sksize = 0;
 196     /*
 197      * Initialise port and protocol to sensible defaults. (These
 198      * will be overridden by more or less anything.)
 199      */
 200     default_protocol = PROT_SSH;
 201     default_port = 22;
 202
 203     flags = FLAG_STDERR;
 204     /*
 205      * Process the command line.
 206      */
 207     do_defaults(NULL, &cfg);
 208     default_protocol = cfg.protocol;
 209     default_port = cfg.port;
 210     errors = 0;
 211     {
 212         /*
 213          * Override the default protocol if PLINK_PROTOCOL is set.
 214          */
 215         char *p = getenv("PLINK_PROTOCOL");
 216         int i;
 217         if (p) {
 218             for (i = 0; backends[i].backend != NULL; i++) {
 219                 if (!strcmp(backends[i].name, p)) {
 220                     default_protocol = cfg.protocol = backends[i].protocol;
 221                     default_port = cfg.port =
 222                         backends[i].backend->default_port;
 223                     break;
 224                 }
 225             }
 226         }
 227     }
 228     while (--argc) {
 229         char *p = *++argv;
 230         if (*p == '-') {
 231             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL), 1);
 232             if (ret == -2) {
 233                 fprintf(stderr,
 234                         "plink: option \"%s\" requires an argument\n", p);
 235                 errors = 1;
 236             } else if (ret == 2) {
 237                 --argc, ++argv;
 238             } else if (ret == 1) {
 239                 continue;
 240             } else if (!strcmp(p, "-batch")) {
 241                 console_batch_mode = 1;
 242             } else if (!strcmp(p, "-o")) {
 243                 if (argc <= 1) {
 244                     fprintf(stderr,
 245                             "plink: option \"-o\" requires an argument\n");
 246                     errors = 1;
 247                 } else {
 248                     --argc;
 249                     provide_xrm_string(*++argv);
 250                 }
 251             } else {
 252                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 253                 errors = 1;
 254             }
 255         } else if (*p) {
 256             if (!*cfg.host) {
 257                 char *q = p;
 258
 259                 do_defaults(NULL, &cfg);
 260
 261                 /*
 262                  * If the hostname starts with "telnet:", set the
 263                  * protocol to Telnet and process the string as a
 264                  * Telnet URL.
 265                  */
 266                 if (!strncmp(q, "telnet:", 7)) {
 267                     char c;
 268
 269                     q += 7;
 270                     if (q[0] == '/' && q[1] == '/')
 271                         q += 2;
 272                     cfg.protocol = PROT_TELNET;
 273                     p = q;
 274                     while (*p && *p != ':' && *p != '/')
 275                         p++;
 276                     c = *p;
 277                     if (*p)
 278                         *p++ = '\0';
 279                     if (c == ':')
 280                         cfg.port = atoi(p);
 281                     else
 282                         cfg.port = -1;
 283                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 284                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 285                 } else {
 286                     char *r;
 287                     /*
 288                      * Before we process the [user@]host string, we
 289                      * first check for the presence of a protocol
 290                      * prefix (a protocol name followed by ",").
 291                      */
 292                     r = strchr(p, ',');
 293                     if (r) {
 294                         int i, j;
 295                         for (i = 0; backends[i].backend != NULL; i++) {
 296                             j = strlen(backends[i].name);
 297                             if (j == r - p &&
 298                                 !memcmp(backends[i].name, p, j)) {
 299                                 default_protocol = cfg.protocol =
 300                                     backends[i].protocol;
 301                                 portnumber =
 302                                     backends[i].backend->default_port;
 303                                 p = r + 1;
 304                                 break;
 305                             }
 306                         }
 307                     }
 308
 309                     /*
 310                      * Three cases. Either (a) there's a nonzero
 311                      * length string followed by an @, in which
 312                      * case that's user and the remainder is host.
 313                      * Or (b) there's only one string, not counting
 314                      * a potential initial @, and it exists in the
 315                      * saved-sessions database. Or (c) only one
 316                      * string and it _doesn't_ exist in the
 317                      * database.
 318                      */
 319                     r = strrchr(p, '@');
 320                     if (r == p)
 321                         p++, r = NULL; /* discount initial @ */
 322                     if (r == NULL) {
 323                         /*
 324                          * One string.
 325                          */
 326                         Config cfg2;
 327                         do_defaults(p, &cfg2);
 328                         if (cfg2.host[0] == '\0') {
 329                             /* No settings for this host; use defaults */
 330                             strncpy(cfg.host, p, sizeof(cfg.host) - 1);
 331                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 332                             cfg.port = default_port;
 333                         } else {
 334                             cfg = cfg2;
 335                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 336                         }
 337                     } else {
 338                         *r++ = '\0';
 339                         strncpy(cfg.username, p, sizeof(cfg.username) - 1);
 340                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 341                         strncpy(cfg.host, r, sizeof(cfg.host) - 1);
 342                         cfg.host[sizeof(cfg.host) - 1] = '\0';
 343                         cfg.port = default_port;
 344                     }
 345                 }
 346             } else {
 347                 char *command;
 348                 int cmdlen, cmdsize;
 349                 cmdlen = cmdsize = 0;
 350                 command = NULL;
 351
 352                 while (argc) {
 353                     while (*p) {
 354                         if (cmdlen >= cmdsize) {
 355                             cmdsize = cmdlen + 512;
 356                             command = srealloc(command, cmdsize);
 357                         }
 358                         command[cmdlen++]=*p++;
 359                     }
 360                     if (cmdlen >= cmdsize) {
 361                         cmdsize = cmdlen + 512;
 362                         command = srealloc(command, cmdsize);
 363                     }
 364                     command[cmdlen++]=' '; /* always add trailing space */
 365                     if (--argc) p = *++argv;
 366                 }
 367                 if (cmdlen) command[--cmdlen]='\0';
 368                                        /* change trailing blank to NUL */
 369                 cfg.remote_cmd_ptr = command;
 370                 cfg.remote_cmd_ptr2 = NULL;
 371                 cfg.nopty = TRUE;      /* command => no terminal */
 372
 373                 break;                 /* done with cmdline */
 374             }
 375         }
 376     }
 377
 378     if (errors)
 379         return 1;
 380
 381     if (!*cfg.host) {
 382         usage();
 383     }
 384
 385     /*
 386      * Trim leading whitespace off the hostname if it's there.
 387      */
 388     {
 389         int space = strspn(cfg.host, " \t");
 390         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 391     }
 392
 393     /* See if host is of the form user@host */
 394     if (cfg.host[0] != '\0') {
 395         char *atsign = strchr(cfg.host, '@');
 396         /* Make sure we're not overflowing the user field */
 397         if (atsign) {
 398             if (atsign - cfg.host < sizeof cfg.username) {
 399                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 400                 cfg.username[atsign - cfg.host] = '\0';
 401             }
 402             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 403         }
 404     }
 405
 406     /*
 407      * Perform command-line overrides on session configuration.
 408      */
 409     cmdline_run_saved();
 410
 411     /*
 412      * Trim a colon suffix off the hostname if it's there.
 413      */
 414     cfg.host[strcspn(cfg.host, ":")] = '\0';
 415
 416     /*
 417      * Remove any remaining whitespace from the hostname.
 418      */
 419     {
 420         int p1 = 0, p2 = 0;
 421         while (cfg.host[p2] != '\0') {
 422             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 423                 cfg.host[p1] = cfg.host[p2];
 424                 p1++;
 425             }
 426             p2++;
 427         }
 428         cfg.host[p1] = '\0';
 429     }
 430
 431     if (!*cfg.remote_cmd_ptr)
 432         flags |= FLAG_INTERACTIVE;
 433
 434     /*
 435      * Select protocol. This is farmed out into a table in a
 436      * separate file to enable an ssh-free variant.
 437      */
 438     {
 439         int i;
 440         back = NULL;
 441         for (i = 0; backends[i].backend != NULL; i++)
 442             if (backends[i].protocol == cfg.protocol) {
 443                 back = backends[i].backend;
 444                 break;
 445             }
 446         if (back == NULL) {
 447             fprintf(stderr,
 448                     "Internal fault: Unsupported protocol found\n");
 449             return 1;
 450         }
 451     }
 452
 453     /*
 454      * Select port.
 455      */
 456     if (portnumber != -1)
 457         cfg.port = portnumber;
 458
 459     sk_init();
 460
 461     /*
 462      * Start up the connection.
 463      */
 464     logctx = log_init(NULL);
 465     {
 466         char *error;
 467         char *realhost;
 468         /* nodelay is only useful if stdin is a terminal device */
 469         int nodelay = cfg.tcp_nodelay && isatty(0);
 470
 471         error = back->init(NULL, &backhandle, cfg.host, cfg.port,
 472                            &realhost, nodelay);
 473         if (error) {
 474             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 475             return 1;
 476         }
 477         back->provide_logctx(backhandle, logctx);
 478         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 479         sfree(realhost);
 480     }
 481     connopen = 1;
 482
 483     /*
 484      * Set up the initial console mode. We don't care if this call
 485      * fails, because we know we aren't necessarily running in a
 486      * console.
 487      */
 488     tcgetattr(0, &orig_termios);
 489     atexit(cleanup_termios);
 490     ldisc_update(NULL, 1, 1);
 491     sending = FALSE;
 492
 493     while (1) {
 494         fd_set rset, wset, xset;
 495         int maxfd;
 496         int rwx;
 497         int ret;
 498
 499         FD_ZERO(&rset);
 500         FD_ZERO(&wset);
 501         FD_ZERO(&xset);
 502         maxfd = 0;
 503
 504         if (connopen && !sending &&
 505             back->socket(backhandle) != NULL &&
 506             back->sendok(backhandle) &&
 507             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 508             /* If we're OK to send, then try to read from stdin. */
 509             FD_SET_MAX(0, maxfd, rset);
 510         }
 511
 512         if (bufchain_size(&stdout_data) > 0) {
 513             /* If we have data for stdout, try to write to stdout. */
 514             FD_SET_MAX(1, maxfd, wset);
 515         }
 516
 517         if (bufchain_size(&stderr_data) > 0) {
 518             /* If we have data for stderr, try to write to stderr. */
 519             FD_SET_MAX(2, maxfd, wset);
 520         }
 521
 522         /* Count the currently active sockets. */
 523         i = 0;
 524         for (socket = first_socket(&socketstate, &rwx); socket >= 0;
 525              socket = next_socket(&socketstate, &rwx)) i++;
 526
 527         /* Expand the sklist buffer if necessary. */
 528         if (i > sksize) {
 529             sksize = i + 16;
 530             sklist = srealloc(sklist, sksize * sizeof(*sklist));
 531         }
 532
 533         /*
 534          * Add all currently open sockets to the select sets, and
 535          * store them in sklist as well.
 536          */
 537         skcount = 0;
 538         for (socket = first_socket(&socketstate, &rwx); socket >= 0;
 539              socket = next_socket(&socketstate, &rwx)) {
 540             sklist[skcount++] = socket;
 541             if (rwx & 1)
 542                 FD_SET_MAX(socket, maxfd, rset);
 543             if (rwx & 2)
 544                 FD_SET_MAX(socket, maxfd, wset);
 545             if (rwx & 4)
 546                 FD_SET_MAX(socket, maxfd, xset);
 547         }
 548
 549         ret = select(maxfd, &rset, &wset, &xset, NULL);
 550
 551         if (ret < 0) {
 552             perror("select");
 553             exit(1);
 554         }
 555
 556         for (i = 0; i < skcount; i++) {
 557             socket = sklist[i];
 558             /*
 559              * We must process exceptional notifications before
 560              * ordinary readability ones, or we may go straight
 561              * past the urgent marker.
 562              */
 563             if (FD_ISSET(socket, &xset))
 564                 select_result(socket, 4);
 565             if (FD_ISSET(socket, &rset))
 566                 select_result(socket, 1);
 567             if (FD_ISSET(socket, &wset))
 568                 select_result(socket, 2);
 569         }
 570
 571         if (FD_ISSET(0, &rset)) {
 572             char buf[4096];
 573             int ret;
 574
 575             if (connopen && back->socket(backhandle) != NULL) {
 576                 ret = read(0, buf, sizeof(buf));
 577                 if (ret < 0) {
 578                     perror("stdin: read");
 579                     exit(1);
 580                 } else if (ret == 0) {
 581                     back->special(backhandle, TS_EOF);
 582                     sending = FALSE;   /* send nothing further after this */
 583                 } else {
 584                     back->send(backhandle, buf, ret);
 585                 }
 586             }
 587         }
 588
 589         if (FD_ISSET(1, &wset)) {
 590             try_output(0);
 591         }
 592
 593         if (FD_ISSET(2, &wset)) {
 594             try_output(1);
 595         }
 596
 597         if ((!connopen || back->socket(backhandle) == NULL) &&
 598             bufchain_size(&stdout_data) == 0 &&
 599             bufchain_size(&stderr_data) == 0)
 600             break;                     /* we closed the connection */
 601     }
 602     exitcode = back->exitcode(backhandle);
 603     if (exitcode < 0) {
 604         fprintf(stderr, "Remote process exit code unavailable\n");
 605         exitcode = 1;                  /* this is an error condition */
 606     }
 607     cleanup_exit(exitcode);
 608     return exitcode;                   /* shouldn't happen, but placates gcc */
 609 }