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     void *ldisc;
 190
 191     ssh_get_line = console_get_line;
 192
 193     sklist = NULL;
 194     skcount = sksize = 0;
 195     /*
 196      * Initialise port and protocol to sensible defaults. (These
 197      * will be overridden by more or less anything.)
 198      */
 199     default_protocol = PROT_SSH;
 200     default_port = 22;
 201
 202     flags = FLAG_STDERR;
 203     /*
 204      * Process the command line.
 205      */
 206     do_defaults(NULL, &cfg);
 207     default_protocol = cfg.protocol;
 208     default_port = cfg.port;
 209     {
 210         /*
 211          * Override the default protocol if PLINK_PROTOCOL is set.
 212          */
 213         char *p = getenv("PLINK_PROTOCOL");
 214         int i;
 215         if (p) {
 216             for (i = 0; backends[i].backend != NULL; i++) {
 217                 if (!strcmp(backends[i].name, p)) {
 218                     default_protocol = cfg.protocol = backends[i].protocol;
 219                     default_port = cfg.port =
 220                         backends[i].backend->default_port;
 221                     break;
 222                 }
 223             }
 224         }
 225     }
 226     while (--argc) {
 227         char *p = *++argv;
 228         if (*p == '-') {
 229             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL), 1);
 230             if (ret == -2) {
 231                 fprintf(stderr,
 232                         "plink: option \"%s\" requires an argument\n", p);
 233             } else if (ret == 2) {
 234                 --argc, ++argv;
 235             } else if (ret == 1) {
 236                 continue;
 237             } else if (!strcmp(p, "-batch")) {
 238                 console_batch_mode = 1;
 239             } else if (!strcmp(p, "-o")) {
 240                 if (argc <= 1)
 241                     fprintf(stderr,
 242                             "plink: option \"-o\" requires an argument\n");
 243                 else
 244                     --argc, provide_xrm_string(*++argv);
 245             }
 246         } else if (*p) {
 247             if (!*cfg.host) {
 248                 char *q = p;
 249
 250                 do_defaults(NULL, &cfg);
 251
 252                 /*
 253                  * If the hostname starts with "telnet:", set the
 254                  * protocol to Telnet and process the string as a
 255                  * Telnet URL.
 256                  */
 257                 if (!strncmp(q, "telnet:", 7)) {
 258                     char c;
 259
 260                     q += 7;
 261                     if (q[0] == '/' && q[1] == '/')
 262                         q += 2;
 263                     cfg.protocol = PROT_TELNET;
 264                     p = q;
 265                     while (*p && *p != ':' && *p != '/')
 266                         p++;
 267                     c = *p;
 268                     if (*p)
 269                         *p++ = '\0';
 270                     if (c == ':')
 271                         cfg.port = atoi(p);
 272                     else
 273                         cfg.port = -1;
 274                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 275                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 276                 } else {
 277                     char *r;
 278                     /*
 279                      * Before we process the [user@]host string, we
 280                      * first check for the presence of a protocol
 281                      * prefix (a protocol name followed by ",").
 282                      */
 283                     r = strchr(p, ',');
 284                     if (r) {
 285                         int i, j;
 286                         for (i = 0; backends[i].backend != NULL; i++) {
 287                             j = strlen(backends[i].name);
 288                             if (j == r - p &&
 289                                 !memcmp(backends[i].name, p, j)) {
 290                                 default_protocol = cfg.protocol =
 291                                     backends[i].protocol;
 292                                 portnumber =
 293                                     backends[i].backend->default_port;
 294                                 p = r + 1;
 295                                 break;
 296                             }
 297                         }
 298                     }
 299
 300                     /*
 301                      * Three cases. Either (a) there's a nonzero
 302                      * length string followed by an @, in which
 303                      * case that's user and the remainder is host.
 304                      * Or (b) there's only one string, not counting
 305                      * a potential initial @, and it exists in the
 306                      * saved-sessions database. Or (c) only one
 307                      * string and it _doesn't_ exist in the
 308                      * database.
 309                      */
 310                     r = strrchr(p, '@');
 311                     if (r == p)
 312                         p++, r = NULL; /* discount initial @ */
 313                     if (r == NULL) {
 314                         /*
 315                          * One string.
 316                          */
 317                         Config cfg2;
 318                         do_defaults(p, &cfg2);
 319                         if (cfg2.host[0] == '\0') {
 320                             /* No settings for this host; use defaults */
 321                             strncpy(cfg.host, p, sizeof(cfg.host) - 1);
 322                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 323                             cfg.port = default_port;
 324                         } else {
 325                             cfg = cfg2;
 326                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 327                         }
 328                     } else {
 329                         *r++ = '\0';
 330                         strncpy(cfg.username, p, sizeof(cfg.username) - 1);
 331                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 332                         strncpy(cfg.host, r, sizeof(cfg.host) - 1);
 333                         cfg.host[sizeof(cfg.host) - 1] = '\0';
 334                         cfg.port = default_port;
 335                     }
 336                 }
 337             } else {
 338                 char *command;
 339                 int cmdlen, cmdsize;
 340                 cmdlen = cmdsize = 0;
 341                 command = NULL;
 342
 343                 while (argc) {
 344                     while (*p) {
 345                         if (cmdlen >= cmdsize) {
 346                             cmdsize = cmdlen + 512;
 347                             command = srealloc(command, cmdsize);
 348                         }
 349                         command[cmdlen++]=*p++;
 350                     }
 351                     if (cmdlen >= cmdsize) {
 352                         cmdsize = cmdlen + 512;
 353                         command = srealloc(command, cmdsize);
 354                     }
 355                     command[cmdlen++]=' '; /* always add trailing space */
 356                     if (--argc) p = *++argv;
 357                 }
 358                 if (cmdlen) command[--cmdlen]='\0';
 359                                        /* change trailing blank to NUL */
 360                 cfg.remote_cmd_ptr = command;
 361                 cfg.remote_cmd_ptr2 = NULL;
 362                 cfg.nopty = TRUE;      /* command => no terminal */
 363
 364                 break;                 /* done with cmdline */
 365             }
 366         }
 367     }
 368
 369     if (!*cfg.host) {
 370         usage();
 371     }
 372
 373     /*
 374      * Trim leading whitespace off the hostname if it's there.
 375      */
 376     {
 377         int space = strspn(cfg.host, " \t");
 378         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 379     }
 380
 381     /* See if host is of the form user@host */
 382     if (cfg.host[0] != '\0') {
 383         char *atsign = strchr(cfg.host, '@');
 384         /* Make sure we're not overflowing the user field */
 385         if (atsign) {
 386             if (atsign - cfg.host < sizeof cfg.username) {
 387                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 388                 cfg.username[atsign - cfg.host] = '\0';
 389             }
 390             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 391         }
 392     }
 393
 394     /*
 395      * Perform command-line overrides on session configuration.
 396      */
 397     cmdline_run_saved();
 398
 399     /*
 400      * Trim a colon suffix off the hostname if it's there.
 401      */
 402     cfg.host[strcspn(cfg.host, ":")] = '\0';
 403
 404     /*
 405      * Remove any remaining whitespace from the hostname.
 406      */
 407     {
 408         int p1 = 0, p2 = 0;
 409         while (cfg.host[p2] != '\0') {
 410             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 411                 cfg.host[p1] = cfg.host[p2];
 412                 p1++;
 413             }
 414             p2++;
 415         }
 416         cfg.host[p1] = '\0';
 417     }
 418
 419     if (!*cfg.remote_cmd_ptr)
 420         flags |= FLAG_INTERACTIVE;
 421
 422     /*
 423      * Select protocol. This is farmed out into a table in a
 424      * separate file to enable an ssh-free variant.
 425      */
 426     {
 427         int i;
 428         back = NULL;
 429         for (i = 0; backends[i].backend != NULL; i++)
 430             if (backends[i].protocol == cfg.protocol) {
 431                 back = backends[i].backend;
 432                 break;
 433             }
 434         if (back == NULL) {
 435             fprintf(stderr,
 436                     "Internal fault: Unsupported protocol found\n");
 437             return 1;
 438         }
 439     }
 440
 441     /*
 442      * Select port.
 443      */
 444     if (portnumber != -1)
 445         cfg.port = portnumber;
 446
 447     sk_init();
 448
 449     /*
 450      * Start up the connection.
 451      */
 452     logctx = log_init(NULL);
 453     {
 454         char *error;
 455         char *realhost;
 456         /* nodelay is only useful if stdin is a terminal device */
 457         int nodelay = cfg.tcp_nodelay && isatty(0);
 458
 459         error = back->init(NULL, &backhandle, cfg.host, cfg.port,
 460                            &realhost, nodelay);
 461         if (error) {
 462             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 463             return 1;
 464         }
 465         back->provide_logctx(backhandle, logctx);
 466         ldisc = ldisc_create(NULL, back, backhandle, NULL);
 467         sfree(realhost);
 468     }
 469     connopen = 1;
 470
 471     /*
 472      * Set up the initial console mode. We don't care if this call
 473      * fails, because we know we aren't necessarily running in a
 474      * console.
 475      */
 476     tcgetattr(0, &orig_termios);
 477     atexit(cleanup_termios);
 478     ldisc_update(NULL, 1, 1);
 479     sending = FALSE;
 480
 481     while (1) {
 482         fd_set rset, wset, xset;
 483         int maxfd;
 484         int rwx;
 485         int ret;
 486
 487         FD_ZERO(&rset);
 488         FD_ZERO(&wset);
 489         FD_ZERO(&xset);
 490         maxfd = 0;
 491
 492         if (connopen && !sending &&
 493             back->socket(backhandle) != NULL &&
 494             back->sendok(backhandle) &&
 495             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 496             /* If we're OK to send, then try to read from stdin. */
 497             FD_SET_MAX(0, maxfd, rset);
 498         }
 499
 500         if (bufchain_size(&stdout_data) > 0) {
 501             /* If we have data for stdout, try to write to stdout. */
 502             FD_SET_MAX(1, maxfd, wset);
 503         }
 504
 505         if (bufchain_size(&stderr_data) > 0) {
 506             /* If we have data for stderr, try to write to stderr. */
 507             FD_SET_MAX(2, maxfd, wset);
 508         }
 509
 510         /* Count the currently active sockets. */
 511         i = 0;
 512         for (socket = first_socket(&socketstate, &rwx); socket >= 0;
 513              socket = next_socket(&socketstate, &rwx)) i++;
 514
 515         /* Expand the sklist buffer if necessary. */
 516         if (i > sksize) {
 517             sksize = i + 16;
 518             sklist = srealloc(sklist, sksize * sizeof(*sklist));
 519         }
 520
 521         /*
 522          * Add all currently open sockets to the select sets, and
 523          * store them in sklist as well.
 524          */
 525         skcount = 0;
 526         for (socket = first_socket(&socketstate, &rwx); socket >= 0;
 527              socket = next_socket(&socketstate, &rwx)) {
 528             sklist[skcount++] = socket;
 529             if (rwx & 1)
 530                 FD_SET_MAX(socket, maxfd, rset);
 531             if (rwx & 2)
 532                 FD_SET_MAX(socket, maxfd, wset);
 533             if (rwx & 4)
 534                 FD_SET_MAX(socket, maxfd, xset);
 535         }
 536
 537         ret = select(maxfd, &rset, &wset, &xset, NULL);
 538
 539         if (ret < 0) {
 540             perror("select");
 541             exit(1);
 542         }
 543
 544         for (i = 0; i < skcount; i++) {
 545             socket = sklist[i];
 546             /*
 547              * We must process exceptional notifications before
 548              * ordinary readability ones, or we may go straight
 549              * past the urgent marker.
 550              */
 551             if (FD_ISSET(socket, &xset))
 552                 select_result(socket, 4);
 553             if (FD_ISSET(socket, &rset))
 554                 select_result(socket, 1);
 555             if (FD_ISSET(socket, &wset))
 556                 select_result(socket, 2);
 557         }
 558
 559         if (FD_ISSET(0, &rset)) {
 560             char buf[4096];
 561             int ret;
 562
 563             if (connopen && back->socket(backhandle) != NULL) {
 564                 ret = read(0, buf, sizeof(buf));
 565                 if (ret < 0) {
 566                     perror("stdin: read");
 567                     exit(1);
 568                 } else if (ret == 0) {
 569                     back->special(backhandle, TS_EOF);
 570                     sending = FALSE;   /* send nothing further after this */
 571                 } else {
 572                     back->send(backhandle, buf, ret);
 573                 }
 574             }
 575         }
 576
 577         if (FD_ISSET(1, &wset)) {
 578             try_output(0);
 579         }
 580
 581         if (FD_ISSET(2, &wset)) {
 582             try_output(1);
 583         }
 584
 585         if ((!connopen || back->socket(backhandle) == NULL) &&
 586             bufchain_size(&stdout_data) == 0 &&
 587             bufchain_size(&stderr_data) == 0)
 588             break;                     /* we closed the connection */
 589     }
 590     exitcode = back->exitcode(backhandle);
 591     if (exitcode < 0) {
 592         fprintf(stderr, "Remote process exit code unavailable\n");
 593         exitcode = 1;                  /* this is an error condition */
 594     }
 595     cleanup_exit(exitcode);
 596     return exitcode;                   /* shouldn't happen, but placates gcc */
 597 }