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