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("  -4 -6     force use of IPv4 or IPv6\n");
 231     printf("  -C        enable compression\n");
 232     printf("  -i key    private key file for authentication\n");
 233     printf("  -s        remote command is an SSH subsystem (SSH-2 only)\n");
 234     printf("  -N        don't start a shell/command (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     long now;
 257
 258     ssh_get_line = console_get_line;
 259
 260     fdlist = NULL;
 261     fdcount = fdsize = 0;
 262     /*
 263      * Initialise port and protocol to sensible defaults. (These
 264      * will be overridden by more or less anything.)
 265      */
 266     default_protocol = PROT_SSH;
 267     default_port = 22;
 268
 269     flags = FLAG_STDERR;
 270     /*
 271      * Process the command line.
 272      */
 273     do_defaults(NULL, &cfg);
 274     loaded_session = FALSE;
 275     default_protocol = cfg.protocol;
 276     default_port = cfg.port;
 277     errors = 0;
 278     {
 279         /*
 280          * Override the default protocol if PLINK_PROTOCOL is set.
 281          */
 282         char *p = getenv("PLINK_PROTOCOL");
 283         int i;
 284         if (p) {
 285             for (i = 0; backends[i].backend != NULL; i++) {
 286                 if (!strcmp(backends[i].name, p)) {
 287                     default_protocol = cfg.protocol = backends[i].protocol;
 288                     default_port = cfg.port =
 289                         backends[i].backend->default_port;
 290                     break;
 291                 }
 292             }
 293         }
 294     }
 295     while (--argc) {
 296         char *p = *++argv;
 297         if (*p == '-') {
 298             int ret = cmdline_process_param(p, (argc > 1 ? argv[1] : NULL),
 299                                             1, &cfg);
 300             if (ret == -2) {
 301                 fprintf(stderr,
 302                         "plink: option \"%s\" requires an argument\n", p);
 303                 errors = 1;
 304             } else if (ret == 2) {
 305                 --argc, ++argv;
 306             } else if (ret == 1) {
 307                 continue;
 308             } else if (!strcmp(p, "-batch")) {
 309                 console_batch_mode = 1;
 310             } else if (!strcmp(p, "-s")) {
 311                 /* Save status to write to cfg later. */
 312                 use_subsystem = 1;
 313             } else if (!strcmp(p, "-V")) {
 314                 version();
 315             } else if (!strcmp(p, "-o")) {
 316                 if (argc <= 1) {
 317                     fprintf(stderr,
 318                             "plink: option \"-o\" requires an argument\n");
 319                     errors = 1;
 320                 } else {
 321                     --argc;
 322                     provide_xrm_string(*++argv);
 323                 }
 324             } else {
 325                 fprintf(stderr, "plink: unknown option \"%s\"\n", p);
 326                 errors = 1;
 327             }
 328         } else if (*p) {
 329             if (!*cfg.host) {
 330                 char *q = p;
 331
 332                 do_defaults(NULL, &cfg);
 333
 334                 /*
 335                  * If the hostname starts with "telnet:", set the
 336                  * protocol to Telnet and process the string as a
 337                  * Telnet URL.
 338                  */
 339                 if (!strncmp(q, "telnet:", 7)) {
 340                     char c;
 341
 342                     q += 7;
 343                     if (q[0] == '/' && q[1] == '/')
 344                         q += 2;
 345                     cfg.protocol = PROT_TELNET;
 346                     p = q;
 347                     while (*p && *p != ':' && *p != '/')
 348                         p++;
 349                     c = *p;
 350                     if (*p)
 351                         *p++ = '\0';
 352                     if (c == ':')
 353                         cfg.port = atoi(p);
 354                     else
 355                         cfg.port = -1;
 356                     strncpy(cfg.host, q, sizeof(cfg.host) - 1);
 357                     cfg.host[sizeof(cfg.host) - 1] = '\0';
 358                 } else {
 359                     char *r, *user, *host;
 360                     /*
 361                      * Before we process the [user@]host string, we
 362                      * first check for the presence of a protocol
 363                      * prefix (a protocol name followed by ",").
 364                      */
 365                     r = strchr(p, ',');
 366                     if (r) {
 367                         int i, j;
 368                         for (i = 0; backends[i].backend != NULL; i++) {
 369                             j = strlen(backends[i].name);
 370                             if (j == r - p &&
 371                                 !memcmp(backends[i].name, p, j)) {
 372                                 default_protocol = cfg.protocol =
 373                                     backends[i].protocol;
 374                                 portnumber =
 375                                     backends[i].backend->default_port;
 376                                 p = r + 1;
 377                                 break;
 378                             }
 379                         }
 380                     }
 381
 382                     /*
 383                      * A nonzero length string followed by an @ is treated
 384                      * as a username. (We discount an _initial_ @.) The
 385                      * rest of the string (or the whole string if no @)
 386                      * is treated as a session name and/or hostname.
 387                      */
 388                     r = strrchr(p, '@');
 389                     if (r == p)
 390                         p++, r = NULL; /* discount initial @ */
 391                     if (r) {
 392                         *r++ = '\0';
 393                         user = p, host = r;
 394                     } else {
 395                         user = NULL, host = p;
 396                     }
 397
 398                     /*
 399                      * Now attempt to load a saved session with the
 400                      * same name as the hostname.
 401                      */
 402                     {
 403                         Config cfg2;
 404                         do_defaults(host, &cfg2);
 405                         if (loaded_session || cfg2.host[0] == '\0') {
 406                             /* No settings for this host; use defaults */
 407                             /* (or session was already loaded with -load) */
 408                             strncpy(cfg.host, host, sizeof(cfg.host) - 1);
 409                             cfg.host[sizeof(cfg.host) - 1] = '\0';
 410                             cfg.port = default_port;
 411                         } else {
 412                             cfg = cfg2;
 413                             /* Ick: patch up internal pointer after copy */
 414                             cfg.remote_cmd_ptr = cfg.remote_cmd;
 415                         }
 416                     }
 417
 418                     if (user) {
 419                         /* Patch in specified username. */
 420                         strncpy(cfg.username, user,
 421                                 sizeof(cfg.username) - 1);
 422                         cfg.username[sizeof(cfg.username) - 1] = '\0';
 423                     }
 424
 425                 }
 426             } else {
 427                 char *command;
 428                 int cmdlen, cmdsize;
 429                 cmdlen = cmdsize = 0;
 430                 command = NULL;
 431
 432                 while (argc) {
 433                     while (*p) {
 434                         if (cmdlen >= cmdsize) {
 435                             cmdsize = cmdlen + 512;
 436                             command = sresize(command, cmdsize, char);
 437                         }
 438                         command[cmdlen++]=*p++;
 439                     }
 440                     if (cmdlen >= cmdsize) {
 441                         cmdsize = cmdlen + 512;
 442                         command = sresize(command, cmdsize, char);
 443                     }
 444                     command[cmdlen++]=' '; /* always add trailing space */
 445                     if (--argc) p = *++argv;
 446                 }
 447                 if (cmdlen) command[--cmdlen]='\0';
 448                                        /* change trailing blank to NUL */
 449                 cfg.remote_cmd_ptr = command;
 450                 cfg.remote_cmd_ptr2 = NULL;
 451                 cfg.nopty = TRUE;      /* command => no terminal */
 452
 453                 break;                 /* done with cmdline */
 454             }
 455         }
 456     }
 457
 458     if (errors)
 459         return 1;
 460
 461     if (!*cfg.host) {
 462         usage();
 463     }
 464
 465     /*
 466      * Trim leading whitespace off the hostname if it's there.
 467      */
 468     {
 469         int space = strspn(cfg.host, " \t");
 470         memmove(cfg.host, cfg.host+space, 1+strlen(cfg.host)-space);
 471     }
 472
 473     /* See if host is of the form user@host */
 474     if (cfg.host[0] != '\0') {
 475         char *atsign = strrchr(cfg.host, '@');
 476         /* Make sure we're not overflowing the user field */
 477         if (atsign) {
 478             if (atsign - cfg.host < sizeof cfg.username) {
 479                 strncpy(cfg.username, cfg.host, atsign - cfg.host);
 480                 cfg.username[atsign - cfg.host] = '\0';
 481             }
 482             memmove(cfg.host, atsign + 1, 1 + strlen(atsign + 1));
 483         }
 484     }
 485
 486     /*
 487      * Perform command-line overrides on session configuration.
 488      */
 489     cmdline_run_saved(&cfg);
 490
 491     /*
 492      * Apply subsystem status.
 493      */
 494     if (use_subsystem)
 495         cfg.ssh_subsys = TRUE;
 496
 497     /*
 498      * Trim a colon suffix off the hostname if it's there.
 499      */
 500     cfg.host[strcspn(cfg.host, ":")] = '\0';
 501
 502     /*
 503      * Remove any remaining whitespace from the hostname.
 504      */
 505     {
 506         int p1 = 0, p2 = 0;
 507         while (cfg.host[p2] != '\0') {
 508             if (cfg.host[p2] != ' ' && cfg.host[p2] != '\t') {
 509                 cfg.host[p1] = cfg.host[p2];
 510                 p1++;
 511             }
 512             p2++;
 513         }
 514         cfg.host[p1] = '\0';
 515     }
 516
 517     if (!*cfg.remote_cmd_ptr)
 518         flags |= FLAG_INTERACTIVE;
 519
 520     /*
 521      * Select protocol. This is farmed out into a table in a
 522      * separate file to enable an ssh-free variant.
 523      */
 524     {
 525         int i;
 526         back = NULL;
 527         for (i = 0; backends[i].backend != NULL; i++)
 528             if (backends[i].protocol == cfg.protocol) {
 529                 back = backends[i].backend;
 530                 break;
 531             }
 532         if (back == NULL) {
 533             fprintf(stderr,
 534                     "Internal fault: Unsupported protocol found\n");
 535             return 1;
 536         }
 537     }
 538
 539     /*
 540      * Select port.
 541      */
 542     if (portnumber != -1)
 543         cfg.port = portnumber;
 544
 545     /*
 546      * Set up the pipe we'll use to tell us about SIGWINCH.
 547      */
 548     if (pipe(signalpipe) < 0) {
 549         perror("pipe");
 550         exit(1);
 551     }
 552     putty_signal(SIGWINCH, sigwinch);
 553
 554     sk_init();
 555     uxsel_init();
 556
 557     /*
 558      * Start up the connection.
 559      */
 560     logctx = log_init(NULL, &cfg);
 561     console_provide_logctx(logctx);
 562     {
 563         const char *error;
 564         char *realhost;
 565         /* nodelay is only useful if stdin is a terminal device */
 566         int nodelay = cfg.tcp_nodelay && isatty(0);
 567
 568         error = back->init(NULL, &backhandle, &cfg, cfg.host, cfg.port,
 569                            &realhost, nodelay, cfg.tcp_keepalives);
 570         if (error) {
 571             fprintf(stderr, "Unable to open connection:\n%s\n", error);
 572             return 1;
 573         }
 574         back->provide_logctx(backhandle, logctx);
 575         ldisc = ldisc_create(&cfg, NULL, back, backhandle, NULL);
 576         sfree(realhost);
 577     }
 578     connopen = 1;
 579
 580     /*
 581      * Set up the initial console mode. We don't care if this call
 582      * fails, because we know we aren't necessarily running in a
 583      * console.
 584      */
 585     tcgetattr(0, &orig_termios);
 586     atexit(cleanup_termios);
 587     ldisc_update(NULL, 1, 1);
 588     sending = FALSE;
 589     now = GETTICKCOUNT();
 590
 591     while (1) {
 592         fd_set rset, wset, xset;
 593         int maxfd;
 594         int rwx;
 595         int ret;
 596
 597         FD_ZERO(&rset);
 598         FD_ZERO(&wset);
 599         FD_ZERO(&xset);
 600         maxfd = 0;
 601
 602         FD_SET_MAX(signalpipe[0], maxfd, rset);
 603
 604         if (connopen && !sending &&
 605             back->socket(backhandle) != NULL &&
 606             back->sendok(backhandle) &&
 607             back->sendbuffer(backhandle) < MAX_STDIN_BACKLOG) {
 608             /* If we're OK to send, then try to read from stdin. */
 609             FD_SET_MAX(0, maxfd, rset);
 610         }
 611
 612         if (bufchain_size(&stdout_data) > 0) {
 613             /* If we have data for stdout, try to write to stdout. */
 614             FD_SET_MAX(1, maxfd, wset);
 615         }
 616
 617         if (bufchain_size(&stderr_data) > 0) {
 618             /* If we have data for stderr, try to write to stderr. */
 619             FD_SET_MAX(2, maxfd, wset);
 620         }
 621
 622         /* Count the currently active fds. */
 623         i = 0;
 624         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 625              fd = next_fd(&fdstate, &rwx)) i++;
 626
 627         /* Expand the fdlist buffer if necessary. */
 628         if (i > fdsize) {
 629             fdsize = i + 16;
 630             fdlist = sresize(fdlist, fdsize, int);
 631         }
 632
 633         /*
 634          * Add all currently open fds to the select sets, and store
 635          * them in fdlist as well.
 636          */
 637         fdcount = 0;
 638         for (fd = first_fd(&fdstate, &rwx); fd >= 0;
 639              fd = next_fd(&fdstate, &rwx)) {
 640             fdlist[fdcount++] = fd;
 641             if (rwx & 1)
 642                 FD_SET_MAX(fd, maxfd, rset);
 643             if (rwx & 2)
 644                 FD_SET_MAX(fd, maxfd, wset);
 645             if (rwx & 4)
 646                 FD_SET_MAX(fd, maxfd, xset);
 647         }
 648
 649         do {
 650             long next, ticks;
 651             struct timeval tv, *ptv;
 652
 653             if (run_timers(now, &next)) {
 654                 ticks = next - GETTICKCOUNT();
 655                 if (ticks < 0) ticks = 0;   /* just in case */
 656                 tv.tv_sec = ticks / 1000;
 657                 tv.tv_usec = ticks % 1000 * 1000;
 658                 ptv = &tv;
 659             } else {
 660                 ptv = NULL;
 661             }
 662             ret = select(maxfd, &rset, &wset, &xset, ptv);
 663             if (ret == 0)
 664                 now = next;
 665             else
 666                 now = GETTICKCOUNT();
 667         } while (ret < 0 && errno == EINTR);
 668
 669         if (ret < 0) {
 670             perror("select");
 671             exit(1);
 672         }
 673
 674         for (i = 0; i < fdcount; i++) {
 675             fd = fdlist[i];
 676             /*
 677              * We must process exceptional notifications before
 678              * ordinary readability ones, or we may go straight
 679              * past the urgent marker.
 680              */
 681             if (FD_ISSET(fd, &xset))
 682                 select_result(fd, 4);
 683             if (FD_ISSET(fd, &rset))
 684                 select_result(fd, 1);
 685             if (FD_ISSET(fd, &wset))
 686                 select_result(fd, 2);
 687         }
 688
 689         if (FD_ISSET(signalpipe[0], &rset)) {
 690             char c[1];
 691             struct winsize size;
 692             read(signalpipe[0], c, 1); /* ignore its value; it'll be `x' */
 693             if (ioctl(0, TIOCGWINSZ, (void *)&size) >= 0)
 694                 back->size(backhandle, size.ws_col, size.ws_row);
 695         }
 696
 697         if (FD_ISSET(0, &rset)) {
 698             char buf[4096];
 699             int ret;
 700
 701             if (connopen && back->socket(backhandle) != NULL) {
 702                 ret = read(0, buf, sizeof(buf));
 703                 if (ret < 0) {
 704                     perror("stdin: read");
 705                     exit(1);
 706                 } else if (ret == 0) {
 707                     back->special(backhandle, TS_EOF);
 708                     sending = FALSE;   /* send nothing further after this */
 709                 } else {
 710                     back->send(backhandle, buf, ret);
 711                 }
 712             }
 713         }
 714
 715         if (FD_ISSET(1, &wset)) {
 716             try_output(0);
 717         }
 718
 719         if (FD_ISSET(2, &wset)) {
 720             try_output(1);
 721         }
 722
 723         if ((!connopen || back->socket(backhandle) == NULL) &&
 724             bufchain_size(&stdout_data) == 0 &&
 725             bufchain_size(&stderr_data) == 0)
 726             break;                     /* we closed the connection */
 727     }
 728     exitcode = back->exitcode(backhandle);
 729     if (exitcode < 0) {
 730         fprintf(stderr, "Remote process exit code unavailable\n");
 731         exitcode = 1;                  /* this is an error condition */
 732     }
 733     cleanup_exit(exitcode);
 734     return exitcode;                   /* shouldn't happen, but placates gcc */
 735 }