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, "TermType"))
  77         return dupstr(getenv("TERM"));
  78     if (!strcmp(name, "UserName"))
  79         return get_username();
  80     return NULL;
  81 }
  82
  83 int platform_default_i(const char *name, int def)
  84 {
  85     if (!strcmp(name, "TermWidth") ||
  86         !strcmp(name, "TermHeight")) {
  87         struct winsize size;
  88         if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
  89             return (!strcmp(name, "TermWidth") ? size.ws_col : size.ws_row);
  90     }
  91     return def;
  92 }
  93
  94 FontSpec platform_default_fontspec(const char *name)
  95 {
  96     FontSpec ret;
  97     *ret.name = '\0';
  98     return ret;
  99 }
 100
 101 Filename platform_default_filename(const char *name)
 102 {
 103     Filename ret;
 104     if (!strcmp(name, "LogFileName"))
 105         strcpy(ret.path, "putty.log");
 106     else
 107         *ret.path = '\0';
 108     return ret;
 109 }
 110
 111 char *x_get_default(const char *key)
 112 {
 113     return NULL;                       /* this is a stub */
 114 }
 115 int term_ldisc(Terminal *term, int mode)
 116 {
 117     return FALSE;
 118 }
 119 void ldisc_update(void *frontend, int echo, int edit)
 120 {
 121     /* Update stdin read mode to reflect changes in line discipline. */
 122     struct termios mode;
 123
 124     mode = orig_termios;
 125
 126     if (echo)
 127         mode.c_lflag |= ECHO;
 128     else
 129         mode.c_lflag &= ~ECHO;
 130
 131     if (edit)
 132         mode.c_lflag |= ISIG | ICANON;
 133     else
 134         mode.c_lflag &= ~(ISIG | ICANON);
 135
 136     tcsetattr(0, TCSANOW, &mode);
 137 }
 138
 139 void cleanup_termios(void)
 140 {
 141     tcsetattr(0, TCSANOW, &orig_termios);
 142 }
 143
 144 bufchain stdout_data, stderr_data;
 145
 146 void try_output(int is_stderr)
 147 {
 148     bufchain *chain = (is_stderr ? &stderr_data : &stdout_data);
 149     int fd = (is_stderr ? 2 : 1);
 150     void *senddata;
 151     int sendlen, ret;
 152
 153     if (bufchain_size(chain) == 0)
 154         return;
 155
 156     bufchain_prefix(chain, &senddata, &sendlen);
 157     ret = write(fd, senddata, sendlen);
 158     if (ret > 0)
 159         bufchain_consume(chain, ret);
 160     else if (ret < 0) {
 161         perror(is_stderr ? "stderr: write" : "stdout: write");
 162         exit(1);
 163     }
 164 }
 165
 166 int from_backend(void *frontend_handle, int is_stderr,
 167                  const char *data, int len)
 168 {
 169     int osize, esize;
 170
 171     if (is_stderr) {
 172         bufchain_add(&stderr_data, data, len);
 173         try_output(1);
 174     } else {
 175         bufchain_add(&stdout_data, data, len);
 176         try_output(0);
 177     }
 178
 179     osize = bufchain_size(&stdout_data);
 180     esize = bufchain_size(&stderr_data);
 181
 182     return osize + esize;
 183 }
 184
 185 int signalpipe[2];
 186
 187 void sigwinch(int signum)
 188 {
 189     write(signalpipe[1], "x", 1);
 190 }
 191
 192 /*
 193  * In Plink our selects are synchronous, so these functions are
 194  * empty stubs.
 195  */
 196 int uxsel_input_add(int fd, int rwx) { return 0; }
 197 void uxsel_input_remove(int id) { }
 198
 199 /*
 200  * Short description of parameters.
 201  */
 202 static void usage(void)
 203 {
 204     printf("PuTTY Link: command-line connection utility\n");
 205     printf("%s\n", ver);
 206     printf("Usage: plink [options] [user@]host [command]\n");
 207     printf("       (\"host\" can also be a PuTTY saved session name)\n");
 208     printf("Options:\n");
 209     printf("  -V        print version information\n");
 210     printf("  -v        show verbose messages\n");
 211     printf("  -load sessname  Load settings from saved session\n");
 212     printf("  -ssh -telnet -rlogin -raw\n");
 213     printf("            force use of a particular protocol\n");
 214     printf("  -P port   connect to specified port\n");
 215     printf("  -l user   connect with specified username\n");
 216     printf("  -m file   read remote command(s) from file\n");
 217     printf("  -batch    disable all interactive prompts\n");
 218     printf("The following options only apply to SSH connections:\n");
 219     printf("  -pw passw login with specified password\n");
 220     printf("  -D [listen-IP:]listen-port\n");
 221     printf("            Dynamic SOCKS-based port forwarding\n");
 222     printf("  -L [listen-IP:]listen-port:host:port\n");
 223     printf("            Forward local port to remote address\n");
 224     printf("  -R [listen-IP:]listen-port:host:port\n");
 225     printf("            Forward remote port to 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     printf("  -N        don't start a shell/command (SSH-2 only)\n");
 234     exit(1);
 235 }
 236
 237 static void version(void)
 238 {
 239     printf("plink: %s\n", ver);
 240     exit(1);
 241 }
 242
 243 int main(int argc, char **argv)
 244 {
 245     int sending;
 246     int portnumber = -1;
 247     int *fdlist;
 248     int fd;
 249     int i, fdcount, fdsize, fdstate;
 250     int connopen;
 251     int exitcode;
 252     int errors;
 253     int use_subsystem = 0;
 254     void *ldisc, *logctx;
 255     long now;
 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, *user, *host;
 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                      * A nonzero length string followed by an @ is treated
 383                      * as a username. (We discount an _initial_ @.) The
 384                      * rest of the string (or the whole string if no @)
 385                      * is treated as a session name and/or hostname.
 386                      */
 387                     r = strrchr(p, '@');
 388                     if (r == p)
 389                         p++, r = NULL; /* discount initial @ */
 390                     if (r) {
 391                         *r++ = '\0';
 392                         user = p, host = r;
 393                     } else {
 394                         user = NULL, host = p;
 395                     }
 396
 397                     /*
 398                      * Now attempt to load a saved session with the
 399                      * same name as the hostname.
 400                      */
 401                     {
 402                         Config cfg2;
 403                         do_defaults(host, &cfg2);
 404                         if (loaded_session || cfg2.host[0] == '\0') {
 405                             /* No settings for this host; use defaults */
 406                             /* (or session was already loaded with -load) */
 407                             strncpy(cfg.host, host, sizeof(cfg.host) - 1);
 408                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 409                             cfg.port = default_port;
 410                         } else {
 411                             cfg = cfg2;
 412                             /* Ick: patch up internal pointer after copy */
 413                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 414                         }
 415                     }
 416
 417                     if (user) {
 418                         /* Patch in specified username. */
 419                         strncpy(cfg.username, user,
 420                                 sizeof(cfg.username) - 1);
 421                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 422                     }
 423
 424                 }
 425             } else {
 426                 char *command;
 427                 int cmdlen, cmdsize;
 428                 cmdlen = cmdsize = 0;
 429                 command = NULL;
 430
 431                 while (argc) {
 432                     while (*p) {
 433                         if (cmdlen >= cmdsize) {
 434                             cmdsize = cmdlen + 512;
 435                             command = sresize(command, cmdsize, char);
 436                         }
 437                         command[cmdlen++]=*p++;
 438                     }
 439                     if (cmdlen >= cmdsize) {
 440                         cmdsize = cmdlen + 512;
 441                         command = sresize(command, cmdsize, char);
 442                     }
 443                     command[cmdlen++]=' '; /* always add trailing space */
 444                     if (--argc) p = *++argv;
 445                 }
 446                 if (cmdlen) command[--cmdlen]='\0';
 447                                        /* change trailing blank to NUL */
 448                 cfg.remote_cmd_ptr = command;
 449                 cfg.remote_cmd_ptr2 = NULL;
 450                 cfg.nopty = TRUE;      /* command => no terminal */
 451
 452                 break;                 /* done with cmdline */
 453             }
 454         }
 455     }
 456
 457     if (errors)
 458         return 1;
 459
 460     if (!*cfg.host) {
 461         usage();
 462     }
 463
 464     /*
 465      * Trim leading whitespace off the hostname if it's there.
 466      */
 467     {
 468         int space = strspn(cfg.host, " \t");
 469         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 470     }
 471
 472     /* See if host is of the form user@host */
 473     if (cfg.host[0] != '\0') {
 474         char *atsign = strrchr(cfg.host, '@');
 475         /* Make sure we're not overflowing the user field */
 476         if (atsign) {
 477             if (atsign - cfg.host < sizeof cfg.username) {
 478                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 479                 cfg.username[atsign - cfg.host] = '\0';
 480             }
 481             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 482         }
 483     }
 484
 485     /*
 486      * Perform command-line overrides on session configuration.
 487      */
 488     cmdline_run_saved(&cfg);
 489
 490     /*
 491      * Apply subsystem status.
 492      */
 493     if (use_subsystem)
 494         cfg.ssh_subsys = TRUE;
 495
 496     /*
 497      * Trim a colon suffix off the hostname if it's there.
 498      */
 499     cfg.host[strcspn(cfg.host, ":")] = '\0';
 500
 501     /*
 502      * Remove any remaining whitespace from the hostname.
 503      */
 504     {
 505         int p1 = 0, p2 = 0;
 506         while (cfg.host[p2] != '\0') {
 507             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 508                 cfg.host[p1] = cfg.host[p2];
 509                 p1++;
 510             }
 511             p2++;
 512         }
 513         cfg.host[p1] = '\0';
 514     }
 515
 516     if (!*cfg.remote_cmd_ptr)
 517         flags |= FLAG_INTERACTIVE;
 518
 519     /*
 520      * Select protocol. This is farmed out into a table in a
 521      * separate file to enable an ssh-free variant.
 522      */
 523     {
 524         int i;
 525         back = NULL;
 526         for (i = 0; backends[i].backend != NULL; i++)
 527             if (backends[i].protocol == cfg.protocol) {
 528                 back = backends[i].backend;
 529                 break;
 530             }
 531         if (back == NULL) {
 532             fprintf(stderr,
 533                     "Internal fault: Unsupported protocol found\n");
 534             return 1;
 535         }
 536     }
 537
 538     /*
 539      * Select port.
 540      */
 541     if (portnumber != -1)
 542         cfg.port = portnumber;
 543
 544     /*
 545      * Set up the pipe we'll use to tell us about SIGWINCH.
 546      */
 547     if (pipe(signalpipe) < 0) {
 548         perror("pipe");
 549         exit(1);
 550     }
 551     putty_signal(SIGWINCH, sigwinch);
 552
 553     sk_init();
 554     uxsel_init();
 555
 556     /*
 557      * Start up the connection.
 558      */
 559     logctx = log_init(NULL, &cfg);
 560     console_provide_logctx(logctx);
 561     {
 562         const char *error;
 563         char *realhost;
 564         /* nodelay is only useful if stdin is a terminal device */
 565         int nodelay = cfg.tcp_nodelay && isatty(0);
 566
 567         error = back->init(NULL, &backhandle, &cfg, cfg.host, cfg.port,
 568                            &realhost, nodelay, cfg.tcp_keepalives);
 569         if (error) {
 570             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 571             return 1;
 572         }
 573         back->provide_logctx(backhandle, logctx);
 574         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 575         sfree(realhost);
 576     }
 577     connopen = 1;
 578
 579     /*
 580      * Set up the initial console mode. We don't care if this call
 581      * fails, because we know we aren't necessarily running in a
 582      * console.
 583      */
 584     tcgetattr(0, &orig_termios);
 585     atexit(cleanup_termios);
 586     ldisc_update(NULL, 1, 1);
 587     sending = FALSE;
 588     now = GETTICKCOUNT();
 589
 590     while (1) {
 591         fd_set rset, wset, xset;
 592         int maxfd;
 593         int rwx;
 594         int ret;
 595
 596         FD_ZERO(&rset);
 597         FD_ZERO(&wset);
 598         FD_ZERO(&xset);
 599         maxfd = 0;
 600
 601         FD_SET_MAX(signalpipe[0], maxfd, rset);
 602
 603         if (connopen && !sending &&
 604             back->socket(backhandle) != NULL &&
 605             back->sendok(backhandle) &&
 606             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 607             /* If we're OK to send, then try to read from stdin. */
 608             FD_SET_MAX(0, maxfd, rset);
 609         }
 610
 611         if (bufchain_size(&stdout_data) > 0) {
 612             /* If we have data for stdout, try to write to stdout. */
 613             FD_SET_MAX(1, maxfd, wset);
 614         }
 615
 616         if (bufchain_size(&stderr_data) > 0) {
 617             /* If we have data for stderr, try to write to stderr. */
 618             FD_SET_MAX(2, maxfd, wset);
 619         }
 620
 621         /* Count the currently active fds. */
 622         i = 0;
 623         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 624              fd = next_fd(&fdstate, &rwx)) i++;
 625
 626         /* Expand the fdlist buffer if necessary. */
 627         if (i > fdsize) {
 628             fdsize = i + 16;
 629             fdlist = sresize(fdlist, fdsize, int);
 630         }
 631
 632         /*
 633          * Add all currently open fds to the select sets, and store
 634          * them in fdlist as well.
 635          */
 636         fdcount = 0;
 637         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 638              fd = next_fd(&fdstate, &rwx)) {
 639             fdlist[fdcount++] = fd;
 640             if (rwx & 1)
 641                 FD_SET_MAX(fd, maxfd, rset);
 642             if (rwx & 2)
 643                 FD_SET_MAX(fd, maxfd, wset);
 644             if (rwx & 4)
 645                 FD_SET_MAX(fd, maxfd, xset);
 646         }
 647
 648         do {
 649             long next, ticks;
 650             struct timeval tv, *ptv;
 651
 652             if (run_timers(now, &next)) {
 653                 ticks = next - GETTICKCOUNT();
 654                 if (ticks < 0) ticks = 0;   /* just in case */
 655                 tv.tv_sec = ticks / 1000;
 656                 tv.tv_usec = ticks % 1000 * 1000;
 657                 ptv = &tv;
 658             } else {
 659                 ptv = NULL;
 660             }
 661             ret = select(maxfd, &rset, &wset, &xset, ptv);
 662             if (ret == 0)
 663                 now = next;
 664             else
 665                 now = GETTICKCOUNT();
 666         } while (ret < 0 && errno == EINTR);
 667
 668         if (ret < 0) {
 669             perror("select");
 670             exit(1);
 671         }
 672
 673         for (i = 0; i < fdcount; i++) {
 674             fd = fdlist[i];
 675             /*
 676              * We must process exceptional notifications before
 677              * ordinary readability ones, or we may go straight
 678              * past the urgent marker.
 679              */
 680             if (FD_ISSET(fd, &xset))
 681                 select_result(fd, 4);
 682             if (FD_ISSET(fd, &rset))
 683                 select_result(fd, 1);
 684             if (FD_ISSET(fd, &wset))
 685                 select_result(fd, 2);
 686         }
 687
 688         if (FD_ISSET(signalpipe[0], &rset)) {
 689             char c[1];
 690             struct winsize size;
 691             read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
 692             if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
 693                 back->size(backhandle, size.ws_col, size.ws_row);
 694         }
 695
 696         if (FD_ISSET(0, &rset)) {
 697             char buf[4096];
 698             int ret;
 699
 700             if (connopen && back->socket(backhandle) != NULL) {
 701                 ret = read(0, buf, sizeof(buf));
 702                 if (ret < 0) {
 703                     perror("stdin: read");
 704                     exit(1);
 705                 } else if (ret == 0) {
 706                     back->special(backhandle, TS_EOF);
 707                     sending = FALSE;   /* send nothing further after this */
 708                 } else {
 709                     back->send(backhandle, buf, ret);
 710                 }
 711             }
 712         }
 713
 714         if (FD_ISSET(1, &wset)) {
 715             try_output(0);
 716         }
 717
 718         if (FD_ISSET(2, &wset)) {
 719             try_output(1);
 720         }
 721
 722         if ((!connopen || back->socket(backhandle) == NULL) &&
 723             bufchain_size(&stdout_data) == 0 &&
 724             bufchain_size(&stderr_data) == 0)
 725             break;                     /* we closed the connection */
 726     }
 727     exitcode = back->exitcode(backhandle);
 728     if (exitcode < 0) {
 729         fprintf(stderr, "Remote process exit code unavailable\n");
 730         exitcode = 1;                  /* this is an error condition */
 731     }
 732     cleanup_exit(exitcode);
 733     return exitcode;                   /* shouldn't happen, but placates gcc */
 734 }