Annotation of src/usr.bin/ssh/clientloop.c, Revision 1.119
1.1 deraadt 1: /*
1.12 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
1.33 deraadt 5: * The main loop for the interactive session (client side).
1.20 markus 6: *
1.33 deraadt 7: * As far as I am concerned, the code I have written for this software
8: * can be used freely for any purpose. Any derived versions of this
9: * software must be clearly marked as such, and if the derived work is
10: * incompatible with the protocol description in the RFC file, it must be
11: * called by a name other than "ssh" or "Secure Shell".
12: *
13: *
14: * Copyright (c) 1999 Theo de Raadt. All rights reserved.
15: *
16: * Redistribution and use in source and binary forms, with or without
17: * modification, are permitted provided that the following conditions
18: * are met:
19: * 1. Redistributions of source code must retain the above copyright
20: * notice, this list of conditions and the following disclaimer.
21: * 2. Redistributions in binary form must reproduce the above copyright
22: * notice, this list of conditions and the following disclaimer in the
23: * documentation and/or other materials provided with the distribution.
24: *
25: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.20 markus 35: *
36: *
1.33 deraadt 37: * SSH2 support added by Markus Friedl.
1.78 markus 38: * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
1.20 markus 39: *
1.33 deraadt 40: * Redistribution and use in source and binary forms, with or without
41: * modification, are permitted provided that the following conditions
42: * are met:
43: * 1. Redistributions of source code must retain the above copyright
44: * notice, this list of conditions and the following disclaimer.
45: * 2. Redistributions in binary form must reproduce the above copyright
46: * notice, this list of conditions and the following disclaimer in the
47: * documentation and/or other materials provided with the distribution.
48: *
49: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
50: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
51: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
52: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
53: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
54: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
55: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
56: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
57: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
58: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.12 deraadt 59: */
1.1 deraadt 60:
61: #include "includes.h"
1.119 ! djm 62: RCSID("$OpenBSD: clientloop.c,v 1.118 2004/05/08 00:01:37 deraadt Exp $");
1.1 deraadt 63:
1.45 markus 64: #include "ssh.h"
65: #include "ssh1.h"
66: #include "ssh2.h"
1.1 deraadt 67: #include "xmalloc.h"
68: #include "packet.h"
69: #include "buffer.h"
1.15 markus 70: #include "compat.h"
1.74 markus 71: #include "channels.h"
1.15 markus 72: #include "dispatch.h"
1.30 markus 73: #include "buffer.h"
74: #include "bufaux.h"
1.40 markus 75: #include "key.h"
1.54 markus 76: #include "kex.h"
1.45 markus 77: #include "log.h"
78: #include "readconf.h"
79: #include "clientloop.h"
1.40 markus 80: #include "authfd.h"
1.45 markus 81: #include "atomicio.h"
1.118 deraadt 82: #include "sshpty.h"
1.63 markus 83: #include "misc.h"
1.39 markus 84:
85: /* import options */
86: extern Options options;
87:
1.1 deraadt 88: /* Flag indicating that stdin should be redirected from /dev/null. */
89: extern int stdin_null_flag;
90:
1.116 dtucker 91: /* Flag indicating that no shell has been requested */
92: extern int no_shell_flag;
93:
1.13 markus 94: /*
95: * Name of the host we are connecting to. This is the name given on the
96: * command line, or the HostName specified for the user-supplied name in a
97: * configuration file.
98: */
1.1 deraadt 99: extern char *host;
100:
1.13 markus 101: /*
102: * Flag to indicate that we have received a window change signal which has
103: * not yet been processed. This will cause a message indicating the new
104: * window size to be sent to the server a little later. This is volatile
105: * because this is updated in a signal handler.
106: */
1.88 markus 107: static volatile sig_atomic_t received_window_change_signal = 0;
108: static volatile sig_atomic_t received_signal = 0;
1.1 deraadt 109:
110: /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
111: static int in_non_blocking_mode = 0;
112:
113: /* Common data for the client loop code. */
1.31 markus 114: static int quit_pending; /* Set to non-zero to quit the client loop. */
115: static int escape_char; /* Escape character. */
1.11 markus 116: static int escape_pending; /* Last character was the escape character */
117: static int last_was_cr; /* Last character was a newline. */
118: static int exit_status; /* Used to store the exit status of the command. */
119: static int stdin_eof; /* EOF has been encountered on standard error. */
120: static Buffer stdin_buffer; /* Buffer for stdin data. */
121: static Buffer stdout_buffer; /* Buffer for stdout data. */
122: static Buffer stderr_buffer; /* Buffer for stderr data. */
1.42 markus 123: static u_long stdin_bytes, stdout_bytes, stderr_bytes;
124: static u_int buffer_high;/* Soft max buffer size. */
1.11 markus 125: static int connection_in; /* Connection to server (input). */
126: static int connection_out; /* Connection to server (output). */
1.56 markus 127: static int need_rekeying; /* Set to non-zero if rekeying is requested. */
1.60 markus 128: static int session_closed = 0; /* In SSH2: login session closed. */
1.117 markus 129: static int server_alive_timeouts = 0;
1.1 deraadt 130:
1.77 itojun 131: static void client_init_dispatch(void);
1.16 markus 132: int session_ident = -1;
133:
1.54 markus 134: /*XXX*/
135: extern Kex *xxx_kex;
136:
1.1 deraadt 137: /* Restores stdin to blocking mode. */
138:
1.77 itojun 139: static void
1.49 itojun 140: leave_non_blocking(void)
1.1 deraadt 141: {
1.11 markus 142: if (in_non_blocking_mode) {
143: (void) fcntl(fileno(stdin), F_SETFL, 0);
144: in_non_blocking_mode = 0;
145: }
1.1 deraadt 146: }
147:
1.11 markus 148: /* Puts stdin terminal in non-blocking mode. */
149:
1.77 itojun 150: static void
1.49 itojun 151: enter_non_blocking(void)
1.1 deraadt 152: {
1.11 markus 153: in_non_blocking_mode = 1;
154: (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
1.1 deraadt 155: }
156:
1.13 markus 157: /*
158: * Signal handler for the window change signal (SIGWINCH). This just sets a
159: * flag indicating that the window has changed.
160: */
1.1 deraadt 161:
1.77 itojun 162: static void
1.11 markus 163: window_change_handler(int sig)
1.1 deraadt 164: {
1.11 markus 165: received_window_change_signal = 1;
166: signal(SIGWINCH, window_change_handler);
1.1 deraadt 167: }
168:
1.13 markus 169: /*
170: * Signal handler for signals that cause the program to terminate. These
171: * signals must be trapped to restore terminal modes.
172: */
1.1 deraadt 173:
1.77 itojun 174: static void
1.11 markus 175: signal_handler(int sig)
1.1 deraadt 176: {
1.75 markus 177: received_signal = sig;
178: quit_pending = 1;
1.1 deraadt 179: }
180:
1.13 markus 181: /*
182: * Returns current time in seconds from Jan 1, 1970 with the maximum
183: * available resolution.
184: */
1.1 deraadt 185:
1.77 itojun 186: static double
1.49 itojun 187: get_current_time(void)
1.1 deraadt 188: {
1.11 markus 189: struct timeval tv;
190: gettimeofday(&tv, NULL);
191: return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
1.1 deraadt 192: }
193:
1.13 markus 194: /*
195: * This is called when the interactive is entered. This checks if there is
196: * an EOF coming on stdin. We must check this explicitly, as select() does
197: * not appear to wake up when redirecting from /dev/null.
198: */
1.1 deraadt 199:
1.77 itojun 200: static void
1.49 itojun 201: client_check_initial_eof_on_stdin(void)
1.1 deraadt 202: {
1.11 markus 203: int len;
204: char buf[1];
1.1 deraadt 205:
1.13 markus 206: /*
207: * If standard input is to be "redirected from /dev/null", we simply
208: * mark that we have seen an EOF and send an EOF message to the
209: * server. Otherwise, we try to read a single character; it appears
210: * that for some files, such /dev/null, select() never wakes up for
211: * read for this descriptor, which means that we never get EOF. This
212: * way we will get the EOF if stdin comes from /dev/null or similar.
213: */
1.11 markus 214: if (stdin_null_flag) {
215: /* Fake EOF on stdin. */
216: debug("Sending eof.");
217: stdin_eof = 1;
218: packet_start(SSH_CMSG_EOF);
219: packet_send();
220: } else {
221: enter_non_blocking();
222:
223: /* Check for immediate EOF on stdin. */
224: len = read(fileno(stdin), buf, 1);
225: if (len == 0) {
1.13 markus 226: /* EOF. Record that we have seen it and send EOF to server. */
1.11 markus 227: debug("Sending eof.");
228: stdin_eof = 1;
229: packet_start(SSH_CMSG_EOF);
230: packet_send();
231: } else if (len > 0) {
1.13 markus 232: /*
233: * Got data. We must store the data in the buffer,
234: * and also process it as an escape character if
235: * appropriate.
236: */
1.42 markus 237: if ((u_char) buf[0] == escape_char)
1.11 markus 238: escape_pending = 1;
1.52 markus 239: else
1.11 markus 240: buffer_append(&stdin_buffer, buf, 1);
241: }
242: leave_non_blocking();
243: }
1.1 deraadt 244: }
245:
246:
1.13 markus 247: /*
248: * Make packets from buffered stdin data, and buffer them for sending to the
249: * connection.
250: */
1.1 deraadt 251:
1.77 itojun 252: static void
1.49 itojun 253: client_make_packets_from_stdin_data(void)
1.1 deraadt 254: {
1.42 markus 255: u_int len;
1.1 deraadt 256:
1.11 markus 257: /* Send buffered stdin data to the server. */
258: while (buffer_len(&stdin_buffer) > 0 &&
1.90 deraadt 259: packet_not_very_much_data_to_write()) {
1.11 markus 260: len = buffer_len(&stdin_buffer);
261: /* Keep the packets at reasonable size. */
262: if (len > packet_get_maxsize())
263: len = packet_get_maxsize();
264: packet_start(SSH_CMSG_STDIN_DATA);
265: packet_put_string(buffer_ptr(&stdin_buffer), len);
266: packet_send();
267: buffer_consume(&stdin_buffer, len);
1.52 markus 268: stdin_bytes += len;
1.11 markus 269: /* If we have a pending EOF, send it now. */
270: if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
271: packet_start(SSH_CMSG_EOF);
272: packet_send();
273: }
1.1 deraadt 274: }
275: }
276:
1.13 markus 277: /*
278: * Checks if the client window has changed, and sends a packet about it to
279: * the server if so. The actual change is detected elsewhere (by a software
280: * interrupt on Unix); this just checks the flag and sends a message if
281: * appropriate.
282: */
1.1 deraadt 283:
1.77 itojun 284: static void
1.49 itojun 285: client_check_window_change(void)
1.1 deraadt 286: {
1.16 markus 287: struct winsize ws;
288:
289: if (! received_window_change_signal)
290: return;
291: /** XXX race */
292: received_window_change_signal = 0;
293:
294: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
295: return;
296:
1.37 markus 297: debug2("client_check_window_change: changed");
1.16 markus 298:
299: if (compat20) {
300: channel_request_start(session_ident, "window-change", 0);
301: packet_put_int(ws.ws_col);
302: packet_put_int(ws.ws_row);
303: packet_put_int(ws.ws_xpixel);
304: packet_put_int(ws.ws_ypixel);
305: packet_send();
306: } else {
307: packet_start(SSH_CMSG_WINDOW_SIZE);
308: packet_put_int(ws.ws_row);
309: packet_put_int(ws.ws_col);
310: packet_put_int(ws.ws_xpixel);
311: packet_put_int(ws.ws_ypixel);
312: packet_send();
1.1 deraadt 313: }
314: }
315:
1.117 markus 316: static void
317: client_global_request_reply(int type, u_int32_t seq, void *ctxt)
318: {
319: server_alive_timeouts = 0;
320: client_global_request_reply_fwd(type, seq, ctxt);
321: }
322:
323: static void
324: server_alive_check(void)
325: {
326: if (++server_alive_timeouts > options.server_alive_count_max)
327: packet_disconnect("Timeout, server not responding.");
328: packet_start(SSH2_MSG_GLOBAL_REQUEST);
329: packet_put_cstring("keepalive@openssh.com");
330: packet_put_char(1); /* boolean: want reply */
331: packet_send();
332: }
333:
1.13 markus 334: /*
335: * Waits until the client can do something (some data becomes available on
336: * one of the file descriptors).
337: */
1.1 deraadt 338:
1.77 itojun 339: static void
1.46 markus 340: client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
1.81 markus 341: int *maxfdp, int *nallocp, int rekeying)
1.11 markus 342: {
1.117 markus 343: struct timeval tv, *tvp;
344: int ret;
345:
1.46 markus 346: /* Add any selections by the channel mechanism. */
1.81 markus 347: channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
1.11 markus 348:
1.16 markus 349: if (!compat20) {
1.17 markus 350: /* Read from the connection, unless our buffers are full. */
1.16 markus 351: if (buffer_len(&stdout_buffer) < buffer_high &&
352: buffer_len(&stderr_buffer) < buffer_high &&
353: channel_not_very_much_buffered_data())
1.46 markus 354: FD_SET(connection_in, *readsetp);
1.17 markus 355: /*
356: * Read from stdin, unless we have seen EOF or have very much
357: * buffered data to send to the server.
358: */
359: if (!stdin_eof && packet_not_very_much_data_to_write())
1.46 markus 360: FD_SET(fileno(stdin), *readsetp);
1.17 markus 361:
362: /* Select stdout/stderr if have data in buffer. */
363: if (buffer_len(&stdout_buffer) > 0)
1.46 markus 364: FD_SET(fileno(stdout), *writesetp);
1.17 markus 365: if (buffer_len(&stderr_buffer) > 0)
1.46 markus 366: FD_SET(fileno(stderr), *writesetp);
1.16 markus 367: } else {
1.71 markus 368: /* channel_prepare_select could have closed the last channel */
1.84 markus 369: if (session_closed && !channel_still_open() &&
370: !packet_have_data_to_write()) {
371: /* clear mask since we did not call select() */
1.87 markus 372: memset(*readsetp, 0, *nallocp);
373: memset(*writesetp, 0, *nallocp);
1.84 markus 374: return;
1.71 markus 375: } else {
376: FD_SET(connection_in, *readsetp);
377: }
1.16 markus 378: }
1.11 markus 379:
380: /* Select server connection if have data to write to the server. */
381: if (packet_have_data_to_write())
1.46 markus 382: FD_SET(connection_out, *writesetp);
1.11 markus 383:
1.13 markus 384: /*
385: * Wait for something to happen. This will suspend the process until
386: * some selected descriptor can be read, written, or has some other
1.117 markus 387: * event pending.
1.13 markus 388: */
1.11 markus 389:
1.117 markus 390: if (options.server_alive_interval == 0 || !compat20)
391: tvp = NULL;
392: else {
393: tv.tv_sec = options.server_alive_interval;
394: tv.tv_usec = 0;
395: tvp = &tv;
396: }
397: ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
398: if (ret < 0) {
1.11 markus 399: char buf[100];
1.51 markus 400:
401: /*
402: * We have to clear the select masks, because we return.
403: * We have to return, because the mainloop checks for the flags
404: * set by the signal handlers.
405: */
1.87 markus 406: memset(*readsetp, 0, *nallocp);
407: memset(*writesetp, 0, *nallocp);
1.50 deraadt 408:
1.11 markus 409: if (errno == EINTR)
410: return;
411: /* Note: we might still have data in the buffers. */
412: snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
413: buffer_append(&stderr_buffer, buf, strlen(buf));
414: quit_pending = 1;
1.117 markus 415: } else if (ret == 0)
416: server_alive_check();
1.11 markus 417: }
418:
1.77 itojun 419: static void
1.31 markus 420: client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
1.1 deraadt 421: {
1.11 markus 422: struct winsize oldws, newws;
423:
424: /* Flush stdout and stderr buffers. */
1.31 markus 425: if (buffer_len(bout) > 0)
1.112 deraadt 426: atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
1.31 markus 427: if (buffer_len(berr) > 0)
1.112 deraadt 428: atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
1.11 markus 429:
430: leave_raw_mode();
431:
1.13 markus 432: /*
433: * Free (and clear) the buffer to reduce the amount of data that gets
434: * written to swap.
435: */
1.31 markus 436: buffer_free(bin);
437: buffer_free(bout);
438: buffer_free(berr);
1.11 markus 439:
440: /* Save old window size. */
441: ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
442:
443: /* Send the suspend signal to the program itself. */
444: kill(getpid(), SIGTSTP);
445:
446: /* Check if the window size has changed. */
447: if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
448: (oldws.ws_row != newws.ws_row ||
1.90 deraadt 449: oldws.ws_col != newws.ws_col ||
450: oldws.ws_xpixel != newws.ws_xpixel ||
451: oldws.ws_ypixel != newws.ws_ypixel))
1.11 markus 452: received_window_change_signal = 1;
453:
454: /* OK, we have been continued by the user. Reinitialize buffers. */
1.31 markus 455: buffer_init(bin);
456: buffer_init(bout);
457: buffer_init(berr);
1.11 markus 458:
459: enter_raw_mode();
460: }
461:
1.77 itojun 462: static void
1.17 markus 463: client_process_net_input(fd_set * readset)
1.11 markus 464: {
1.17 markus 465: int len;
466: char buf[8192];
1.11 markus 467:
1.13 markus 468: /*
469: * Read input from the server, and add any such data to the buffer of
470: * the packet subsystem.
471: */
1.11 markus 472: if (FD_ISSET(connection_in, readset)) {
473: /* Read as much as possible. */
474: len = read(connection_in, buf, sizeof(buf));
475: if (len == 0) {
476: /* Received EOF. The remote host has closed the connection. */
477: snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
478: host);
1.1 deraadt 479: buffer_append(&stderr_buffer, buf, strlen(buf));
480: quit_pending = 1;
481: return;
1.11 markus 482: }
1.13 markus 483: /*
484: * There is a kernel bug on Solaris that causes select to
485: * sometimes wake up even though there is no data available.
486: */
1.53 millert 487: if (len < 0 && (errno == EAGAIN || errno == EINTR))
1.11 markus 488: len = 0;
489:
490: if (len < 0) {
491: /* An error has encountered. Perhaps there is a network problem. */
492: snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
493: host, strerror(errno));
494: buffer_append(&stderr_buffer, buf, strlen(buf));
495: quit_pending = 1;
496: return;
497: }
498: packet_process_incoming(buf, len);
499: }
1.17 markus 500: }
1.16 markus 501:
1.97 jakob 502: static void
1.99 markus 503: process_cmdline(void)
1.97 jakob 504: {
505: void (*handler)(int);
506: char *s, *cmd;
507: u_short fwd_port, fwd_host_port;
508: char buf[1024], sfwd_port[6], sfwd_host_port[6];
509: int local = 0;
510:
511: leave_raw_mode();
1.101 markus 512: handler = signal(SIGINT, SIG_IGN);
1.99 markus 513: cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
1.97 jakob 514: if (s == NULL)
515: goto out;
516: while (*s && isspace(*s))
517: s++;
518: if (*s == 0)
519: goto out;
520: if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
1.109 itojun 521: logit("Invalid command.");
1.97 jakob 522: goto out;
523: }
524: if (s[1] == 'L')
525: local = 1;
526: if (!local && !compat20) {
1.109 itojun 527: logit("Not supported for SSH protocol version 1.");
1.97 jakob 528: goto out;
529: }
530: s += 2;
531: while (*s && isspace(*s))
532: s++;
533:
534: if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
535: sfwd_port, buf, sfwd_host_port) != 3 &&
536: sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
537: sfwd_port, buf, sfwd_host_port) != 3) {
1.109 itojun 538: logit("Bad forwarding specification.");
1.97 jakob 539: goto out;
540: }
541: if ((fwd_port = a2port(sfwd_port)) == 0 ||
542: (fwd_host_port = a2port(sfwd_host_port)) == 0) {
1.109 itojun 543: logit("Bad forwarding port(s).");
1.97 jakob 544: goto out;
545: }
546: if (local) {
1.99 markus 547: if (channel_setup_local_fwd_listener(fwd_port, buf,
548: fwd_host_port, options.gateway_ports) < 0) {
1.109 itojun 549: logit("Port forwarding failed.");
1.97 jakob 550: goto out;
551: }
552: } else
553: channel_request_remote_forwarding(fwd_port, buf,
554: fwd_host_port);
1.109 itojun 555: logit("Forwarding port.");
1.97 jakob 556: out:
557: signal(SIGINT, handler);
558: enter_raw_mode();
559: if (cmd)
560: xfree(cmd);
561: }
562:
1.31 markus 563: /* process the characters one by one */
1.77 itojun 564: static int
1.31 markus 565: process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
566: {
1.32 markus 567: char string[1024];
1.31 markus 568: pid_t pid;
569: int bytes = 0;
1.42 markus 570: u_int i;
571: u_char ch;
1.31 markus 572: char *s;
573:
574: for (i = 0; i < len; i++) {
575: /* Get one character at a time. */
576: ch = buf[i];
577:
578: if (escape_pending) {
579: /* We have previously seen an escape character. */
580: /* Clear the flag now. */
581: escape_pending = 0;
582:
583: /* Process the escaped character. */
584: switch (ch) {
585: case '.':
586: /* Terminate the connection. */
1.32 markus 587: snprintf(string, sizeof string, "%c.\r\n", escape_char);
588: buffer_append(berr, string, strlen(string));
1.31 markus 589:
590: quit_pending = 1;
591: return -1;
592:
593: case 'Z' - 64:
594: /* Suspend the program. */
595: /* Print a message to that effect to the user. */
1.32 markus 596: snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
597: buffer_append(berr, string, strlen(string));
1.31 markus 598:
599: /* Restore terminal modes and suspend. */
600: client_suspend_self(bin, bout, berr);
601:
602: /* We have been continued. */
603: continue;
604:
1.111 markus 605: case 'B':
606: if (compat20) {
607: snprintf(string, sizeof string,
608: "%cB\r\n", escape_char);
609: buffer_append(berr, string,
610: strlen(string));
611: channel_request_start(session_ident,
612: "break", 0);
613: packet_put_int(1000);
614: packet_send();
615: }
616: continue;
617:
1.54 markus 618: case 'R':
1.59 markus 619: if (compat20) {
620: if (datafellows & SSH_BUG_NOREKEY)
1.109 itojun 621: logit("Server does not support re-keying");
1.59 markus 622: else
623: need_rekeying = 1;
624: }
1.54 markus 625: continue;
626:
1.31 markus 627: case '&':
628: /*
629: * Detach the program (continue to serve connections,
630: * but put in background and no more new connections).
631: */
632: /* Restore tty modes. */
633: leave_raw_mode();
634:
635: /* Stop listening for new connections. */
1.86 markus 636: channel_stop_listening();
1.31 markus 637:
1.86 markus 638: snprintf(string, sizeof string,
639: "%c& [backgrounded]\n", escape_char);
640: buffer_append(berr, string, strlen(string));
1.31 markus 641:
642: /* Fork into background. */
643: pid = fork();
644: if (pid < 0) {
645: error("fork: %.100s", strerror(errno));
646: continue;
647: }
648: if (pid != 0) { /* This is the parent. */
649: /* The parent just exits. */
650: exit(0);
651: }
652: /* The child continues serving connections. */
1.86 markus 653: if (compat20) {
654: buffer_append(bin, "\004", 1);
655: /* fake EOF on stdin */
656: return -1;
657: } else if (!stdin_eof) {
658: /*
659: * Sending SSH_CMSG_EOF alone does not always appear
660: * to be enough. So we try to send an EOF character
661: * first.
662: */
663: packet_start(SSH_CMSG_STDIN_DATA);
664: packet_put_string("\004", 1);
665: packet_send();
666: /* Close stdin. */
667: stdin_eof = 1;
668: if (buffer_len(bin) == 0) {
669: packet_start(SSH_CMSG_EOF);
670: packet_send();
671: }
672: }
673: continue;
1.31 markus 674:
675: case '?':
1.32 markus 676: snprintf(string, sizeof string,
1.31 markus 677: "%c?\r\n\
678: Supported escape sequences:\r\n\
1.104 stevesk 679: %c. - terminate connection\r\n\
1.111 markus 680: %cB - send a BREAK to the remote system\r\n\
1.104 stevesk 681: %cC - open a command line\r\n\
682: %cR - Request rekey (SSH protocol 2 only)\r\n\
683: %c^Z - suspend ssh\r\n\
684: %c# - list forwarded connections\r\n\
685: %c& - background ssh (when waiting for connections to terminate)\r\n\
686: %c? - this message\r\n\
687: %c%c - send the escape character by typing it twice\r\n\
1.31 markus 688: (Note that escapes are only recognized immediately after newline.)\r\n",
1.104 stevesk 689: escape_char, escape_char, escape_char, escape_char,
690: escape_char, escape_char, escape_char, escape_char,
1.111 markus 691: escape_char, escape_char, escape_char);
1.32 markus 692: buffer_append(berr, string, strlen(string));
1.31 markus 693: continue;
694:
695: case '#':
1.32 markus 696: snprintf(string, sizeof string, "%c#\r\n", escape_char);
697: buffer_append(berr, string, strlen(string));
1.31 markus 698: s = channel_open_message();
699: buffer_append(berr, s, strlen(s));
700: xfree(s);
1.97 jakob 701: continue;
702:
703: case 'C':
1.99 markus 704: process_cmdline();
1.31 markus 705: continue;
706:
707: default:
708: if (ch != escape_char) {
709: buffer_put_char(bin, escape_char);
710: bytes++;
711: }
712: /* Escaped characters fall through here */
713: break;
714: }
715: } else {
716: /*
717: * The previous character was not an escape char. Check if this
718: * is an escape.
719: */
720: if (last_was_cr && ch == escape_char) {
721: /* It is. Set the flag and continue to next character. */
722: escape_pending = 1;
723: continue;
724: }
725: }
726:
727: /*
728: * Normal character. Record whether it was a newline,
729: * and append it to the buffer.
730: */
731: last_was_cr = (ch == '\r' || ch == '\n');
732: buffer_put_char(bin, ch);
733: bytes++;
734: }
735: return bytes;
736: }
737:
1.77 itojun 738: static void
1.17 markus 739: client_process_input(fd_set * readset)
740: {
1.21 deraadt 741: int len;
1.31 markus 742: char buf[8192];
1.16 markus 743:
1.11 markus 744: /* Read input from stdin. */
745: if (FD_ISSET(fileno(stdin), readset)) {
746: /* Read as much as possible. */
747: len = read(fileno(stdin), buf, sizeof(buf));
1.64 markus 748: if (len < 0 && (errno == EAGAIN || errno == EINTR))
749: return; /* we'll try again later */
1.11 markus 750: if (len <= 0) {
1.13 markus 751: /*
752: * Received EOF or error. They are treated
753: * similarly, except that an error message is printed
754: * if it was an error condition.
755: */
1.11 markus 756: if (len < 0) {
757: snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
758: buffer_append(&stderr_buffer, buf, strlen(buf));
759: }
760: /* Mark that we have seen EOF. */
761: stdin_eof = 1;
1.13 markus 762: /*
763: * Send an EOF message to the server unless there is
764: * data in the buffer. If there is data in the
765: * buffer, no message will be sent now. Code
766: * elsewhere will send the EOF when the buffer
767: * becomes empty if stdin_eof is set.
768: */
1.11 markus 769: if (buffer_len(&stdin_buffer) == 0) {
1.1 deraadt 770: packet_start(SSH_CMSG_EOF);
771: packet_send();
1.11 markus 772: }
1.72 stevesk 773: } else if (escape_char == SSH_ESCAPECHAR_NONE) {
1.13 markus 774: /*
775: * Normal successful read, and no escape character.
776: * Just append the data to buffer.
777: */
1.11 markus 778: buffer_append(&stdin_buffer, buf, len);
779: } else {
1.13 markus 780: /*
781: * Normal, successful read. But we have an escape character
782: * and have to process the characters one by one.
783: */
1.52 markus 784: if (process_escapes(&stdin_buffer, &stdout_buffer,
785: &stderr_buffer, buf, len) == -1)
1.31 markus 786: return;
1.11 markus 787: }
788: }
789: }
790:
1.77 itojun 791: static void
1.11 markus 792: client_process_output(fd_set * writeset)
793: {
794: int len;
795: char buf[100];
1.1 deraadt 796:
1.11 markus 797: /* Write buffered output to stdout. */
798: if (FD_ISSET(fileno(stdout), writeset)) {
799: /* Write as much data as possible. */
800: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 801: buffer_len(&stdout_buffer));
1.11 markus 802: if (len <= 0) {
1.64 markus 803: if (errno == EINTR || errno == EAGAIN)
1.11 markus 804: len = 0;
805: else {
1.13 markus 806: /*
807: * An error or EOF was encountered. Put an
808: * error message to stderr buffer.
809: */
1.11 markus 810: snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
811: buffer_append(&stderr_buffer, buf, strlen(buf));
812: quit_pending = 1;
813: return;
814: }
815: }
816: /* Consume printed data from the buffer. */
817: buffer_consume(&stdout_buffer, len);
1.57 markus 818: stdout_bytes += len;
1.11 markus 819: }
820: /* Write buffered output to stderr. */
821: if (FD_ISSET(fileno(stderr), writeset)) {
822: /* Write as much data as possible. */
823: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 824: buffer_len(&stderr_buffer));
1.11 markus 825: if (len <= 0) {
1.64 markus 826: if (errno == EINTR || errno == EAGAIN)
1.11 markus 827: len = 0;
828: else {
1.13 markus 829: /* EOF or error, but can't even print error message. */
1.11 markus 830: quit_pending = 1;
831: return;
832: }
833: }
834: /* Consume printed characters from the buffer. */
835: buffer_consume(&stderr_buffer, len);
1.57 markus 836: stderr_bytes += len;
1.11 markus 837: }
1.1 deraadt 838: }
839:
1.13 markus 840: /*
1.15 markus 841: * Get packets from the connection input buffer, and process them as long as
842: * there are packets available.
843: *
844: * Any unknown packets received during the actual
845: * session cause the session to terminate. This is
846: * intended to make debugging easier since no
847: * confirmations are sent. Any compatible protocol
848: * extensions must be negotiated during the
849: * preparatory phase.
850: */
851:
1.77 itojun 852: static void
1.49 itojun 853: client_process_buffered_input_packets(void)
1.15 markus 854: {
1.54 markus 855: dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
1.15 markus 856: }
857:
1.31 markus 858: /* scan buf[] for '~' before sending data to the peer */
1.30 markus 859:
1.77 itojun 860: static int
1.31 markus 861: simple_escape_filter(Channel *c, char *buf, int len)
1.30 markus 862: {
1.31 markus 863: /* XXX we assume c->extended is writeable */
864: return process_escapes(&c->input, &c->output, &c->extended, buf, len);
1.30 markus 865: }
866:
1.77 itojun 867: static void
1.60 markus 868: client_channel_closed(int id, void *arg)
869: {
870: if (id != session_ident)
871: error("client_channel_closed: id %d != session_ident %d",
872: id, session_ident);
1.83 markus 873: channel_cancel_cleanup(id);
1.60 markus 874: session_closed = 1;
1.113 markus 875: leave_raw_mode();
1.60 markus 876: }
877:
1.15 markus 878: /*
1.13 markus 879: * Implements the interactive session with the server. This is called after
880: * the user has been authenticated, and a command has been started on the
1.72 stevesk 881: * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
882: * used as an escape character for terminating or suspending the session.
1.13 markus 883: */
1.1 deraadt 884:
1.20 markus 885: int
1.30 markus 886: client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1.1 deraadt 887: {
1.46 markus 888: fd_set *readset = NULL, *writeset = NULL;
1.11 markus 889: double start_time, total_time;
1.81 markus 890: int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
1.11 markus 891: char buf[100];
892:
893: debug("Entering interactive session.");
894:
895: start_time = get_current_time();
896:
897: /* Initialize variables. */
898: escape_pending = 0;
899: last_was_cr = 1;
900: exit_status = -1;
901: stdin_eof = 0;
902: buffer_high = 64 * 1024;
903: connection_in = packet_get_connection_in();
904: connection_out = packet_get_connection_out();
1.46 markus 905: max_fd = MAX(connection_in, connection_out);
906:
907: if (!compat20) {
1.63 markus 908: /* enable nonblocking unless tty */
909: if (!isatty(fileno(stdin)))
910: set_nonblock(fileno(stdin));
911: if (!isatty(fileno(stdout)))
912: set_nonblock(fileno(stdout));
913: if (!isatty(fileno(stderr)))
914: set_nonblock(fileno(stderr));
1.46 markus 915: max_fd = MAX(max_fd, fileno(stdin));
916: max_fd = MAX(max_fd, fileno(stdout));
917: max_fd = MAX(max_fd, fileno(stderr));
918: }
1.11 markus 919: stdin_bytes = 0;
920: stdout_bytes = 0;
921: stderr_bytes = 0;
922: quit_pending = 0;
923: escape_char = escape_char_arg;
924:
925: /* Initialize buffers. */
926: buffer_init(&stdin_buffer);
927: buffer_init(&stdout_buffer);
928: buffer_init(&stderr_buffer);
929:
1.15 markus 930: client_init_dispatch();
931:
1.105 markus 932: /*
933: * Set signal handlers, (e.g. to restore non-blocking mode)
934: * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
935: */
936: if (signal(SIGINT, SIG_IGN) != SIG_IGN)
937: signal(SIGINT, signal_handler);
938: if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
939: signal(SIGQUIT, signal_handler);
940: if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
941: signal(SIGTERM, signal_handler);
1.11 markus 942: if (have_pty)
943: signal(SIGWINCH, window_change_handler);
944:
945: if (have_pty)
946: enter_raw_mode();
947:
1.48 markus 948: if (compat20) {
949: session_ident = ssh2_chan_id;
1.72 stevesk 950: if (escape_char != SSH_ESCAPECHAR_NONE)
1.48 markus 951: channel_register_filter(session_ident,
952: simple_escape_filter);
1.60 markus 953: if (session_ident != -1)
954: channel_register_cleanup(session_ident,
955: client_channel_closed);
1.48 markus 956: } else {
957: /* Check if we should immediately send eof on stdin. */
1.16 markus 958: client_check_initial_eof_on_stdin();
1.48 markus 959: }
1.30 markus 960:
1.11 markus 961: /* Main loop of the client for the interactive session mode. */
962: while (!quit_pending) {
963:
1.13 markus 964: /* Process buffered packets sent by the server. */
1.11 markus 965: client_process_buffered_input_packets();
966:
1.60 markus 967: if (compat20 && session_closed && !channel_still_open())
968: break;
969:
1.56 markus 970: rekeying = (xxx_kex != NULL && !xxx_kex->done);
1.16 markus 971:
1.56 markus 972: if (rekeying) {
973: debug("rekeying in progress");
974: } else {
975: /*
976: * Make packets of buffered stdin data, and buffer
977: * them for sending to the server.
978: */
979: if (!compat20)
980: client_make_packets_from_stdin_data();
1.11 markus 981:
1.56 markus 982: /*
983: * Make packets from buffered channel data, and
984: * enqueue them for sending to the server.
985: */
986: if (packet_not_very_much_data_to_write())
987: channel_output_poll();
1.11 markus 988:
1.56 markus 989: /*
990: * Check if the window size has changed, and buffer a
991: * message about it to the server if so.
992: */
993: client_check_window_change();
1.11 markus 994:
1.56 markus 995: if (quit_pending)
996: break;
997: }
1.13 markus 998: /*
999: * Wait until we have something to do (something becomes
1000: * available on one of the descriptors).
1001: */
1.81 markus 1002: max_fd2 = max_fd;
1.56 markus 1003: client_wait_until_can_do_something(&readset, &writeset,
1.81 markus 1004: &max_fd2, &nalloc, rekeying);
1.11 markus 1005:
1006: if (quit_pending)
1007: break;
1008:
1.56 markus 1009: /* Do channel operations unless rekeying in progress. */
1010: if (!rekeying) {
1011: channel_after_select(readset, writeset);
1.108 markus 1012: if (need_rekeying || packet_need_rekeying()) {
1013: debug("need rekeying");
1.56 markus 1014: xxx_kex->done = 0;
1015: kex_send_kexinit(xxx_kex);
1016: need_rekeying = 0;
1017: }
1018: }
1.11 markus 1019:
1.17 markus 1020: /* Buffer input from the connection. */
1.46 markus 1021: client_process_net_input(readset);
1.17 markus 1022:
1023: if (quit_pending)
1024: break;
1.11 markus 1025:
1.17 markus 1026: if (!compat20) {
1027: /* Buffer data from stdin */
1.46 markus 1028: client_process_input(readset);
1.17 markus 1029: /*
1030: * Process output to stdout and stderr. Output to
1031: * the connection is processed elsewhere (above).
1032: */
1.46 markus 1033: client_process_output(writeset);
1.17 markus 1034: }
1.11 markus 1035:
1.13 markus 1036: /* Send as much buffered packet data as possible to the sender. */
1.46 markus 1037: if (FD_ISSET(connection_out, writeset))
1.11 markus 1038: packet_write_poll();
1039: }
1.46 markus 1040: if (readset)
1041: xfree(readset);
1042: if (writeset)
1043: xfree(writeset);
1.11 markus 1044:
1045: /* Terminate the session. */
1046:
1047: /* Stop watching for window change. */
1048: if (have_pty)
1049: signal(SIGWINCH, SIG_DFL);
1050:
1.76 markus 1051: channel_free_all();
1.11 markus 1052:
1.75 markus 1053: if (have_pty)
1054: leave_raw_mode();
1055:
1056: /* restore blocking io */
1057: if (!isatty(fileno(stdin)))
1058: unset_nonblock(fileno(stdin));
1059: if (!isatty(fileno(stdout)))
1060: unset_nonblock(fileno(stdout));
1061: if (!isatty(fileno(stderr)))
1062: unset_nonblock(fileno(stderr));
1.116 dtucker 1063:
1064: /*
1065: * If there was no shell or command requested, there will be no remote
1066: * exit status to be returned. In that case, clear error code if the
1067: * connection was deliberately terminated at this end.
1068: */
1069: if (no_shell_flag && received_signal == SIGTERM) {
1070: received_signal = 0;
1071: exit_status = 0;
1072: }
1.75 markus 1073:
1.113 markus 1074: if (received_signal)
1.89 itojun 1075: fatal("Killed by signal %d.", (int) received_signal);
1.75 markus 1076:
1.13 markus 1077: /*
1078: * In interactive mode (with pseudo tty) display a message indicating
1079: * that the connection has been closed.
1080: */
1.11 markus 1081: if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1082: snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1083: buffer_append(&stderr_buffer, buf, strlen(buf));
1084: }
1.70 markus 1085:
1.11 markus 1086: /* Output any buffered data for stdout. */
1.70 markus 1087: while (buffer_len(&stdout_buffer) > 0) {
1088: len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1.14 deraadt 1089: buffer_len(&stdout_buffer));
1.70 markus 1090: if (len <= 0) {
1.11 markus 1091: error("Write failed flushing stdout buffer.");
1.70 markus 1092: break;
1093: }
1.11 markus 1094: buffer_consume(&stdout_buffer, len);
1.57 markus 1095: stdout_bytes += len;
1.11 markus 1096: }
1097:
1098: /* Output any buffered data for stderr. */
1.70 markus 1099: while (buffer_len(&stderr_buffer) > 0) {
1100: len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1.14 deraadt 1101: buffer_len(&stderr_buffer));
1.70 markus 1102: if (len <= 0) {
1.11 markus 1103: error("Write failed flushing stderr buffer.");
1.70 markus 1104: break;
1105: }
1.11 markus 1106: buffer_consume(&stderr_buffer, len);
1.57 markus 1107: stderr_bytes += len;
1.11 markus 1108: }
1109:
1110: /* Clear and free any buffers. */
1111: memset(buf, 0, sizeof(buf));
1112: buffer_free(&stdin_buffer);
1113: buffer_free(&stdout_buffer);
1114: buffer_free(&stderr_buffer);
1115:
1116: /* Report bytes transferred, and transfer rates. */
1117: total_time = get_current_time() - start_time;
1118: debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1.90 deraadt 1119: stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1.11 markus 1120: if (total_time > 0)
1121: debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1.90 deraadt 1122: stdin_bytes / total_time, stdout_bytes / total_time,
1123: stderr_bytes / total_time);
1.11 markus 1124:
1125: /* Return the exit status of the program. */
1126: debug("Exit status %d", exit_status);
1127: return exit_status;
1.15 markus 1128: }
1129:
1130: /*********/
1131:
1.77 itojun 1132: static void
1.94 markus 1133: client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1134: {
1.42 markus 1135: u_int data_len;
1.15 markus 1136: char *data = packet_get_string(&data_len);
1.93 markus 1137: packet_check_eom();
1.15 markus 1138: buffer_append(&stdout_buffer, data, data_len);
1139: memset(data, 0, data_len);
1140: xfree(data);
1141: }
1.77 itojun 1142: static void
1.94 markus 1143: client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1.15 markus 1144: {
1.42 markus 1145: u_int data_len;
1.15 markus 1146: char *data = packet_get_string(&data_len);
1.93 markus 1147: packet_check_eom();
1.15 markus 1148: buffer_append(&stderr_buffer, data, data_len);
1149: memset(data, 0, data_len);
1150: xfree(data);
1151: }
1.77 itojun 1152: static void
1.94 markus 1153: client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1.15 markus 1154: {
1155: exit_status = packet_get_int();
1.93 markus 1156: packet_check_eom();
1.15 markus 1157: /* Acknowledge the exit. */
1158: packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1159: packet_send();
1160: /*
1161: * Must wait for packet to be sent since we are
1162: * exiting the loop.
1163: */
1164: packet_write_wait();
1165: /* Flag that we want to exit. */
1166: quit_pending = 1;
1167: }
1.115 markus 1168: static void
1169: client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1170: {
1171: Channel *c = NULL;
1172: int remote_id, sock;
1173:
1174: /* Read the remote channel number from the message. */
1175: remote_id = packet_get_int();
1176: packet_check_eom();
1177:
1178: /*
1179: * Get a connection to the local authentication agent (this may again
1180: * get forwarded).
1181: */
1182: sock = ssh_get_authentication_socket();
1183:
1184: /*
1185: * If we could not connect the agent, send an error message back to
1186: * the server. This should never happen unless the agent dies,
1187: * because authentication forwarding is only enabled if we have an
1188: * agent.
1189: */
1190: if (sock >= 0) {
1191: c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1192: -1, 0, 0, 0, "authentication agent connection", 1);
1193: c->remote_id = remote_id;
1194: c->force_drain = 1;
1195: }
1196: if (c == NULL) {
1197: packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1198: packet_put_int(remote_id);
1199: } else {
1200: /* Send a confirmation to the remote host. */
1201: debug("Forwarding authentication connection.");
1202: packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1203: packet_put_int(remote_id);
1204: packet_put_int(c->self);
1205: }
1206: packet_send();
1207: }
1.15 markus 1208:
1.77 itojun 1209: static Channel *
1.40 markus 1210: client_request_forwarded_tcpip(const char *request_type, int rchan)
1211: {
1.103 deraadt 1212: Channel *c = NULL;
1.40 markus 1213: char *listen_address, *originator_address;
1214: int listen_port, originator_port;
1.67 markus 1215: int sock;
1.40 markus 1216:
1217: /* Get rest of the packet */
1218: listen_address = packet_get_string(NULL);
1219: listen_port = packet_get_int();
1220: originator_address = packet_get_string(NULL);
1221: originator_port = packet_get_int();
1.93 markus 1222: packet_check_eom();
1.40 markus 1223:
1224: debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1225: listen_address, listen_port, originator_address, originator_port);
1226:
1.80 stevesk 1227: sock = channel_connect_by_listen_address(listen_port);
1.67 markus 1228: if (sock < 0) {
1229: xfree(originator_address);
1230: xfree(listen_address);
1231: return NULL;
1232: }
1233: c = channel_new("forwarded-tcpip",
1234: SSH_CHANNEL_CONNECTING, sock, sock, -1,
1235: CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1236: originator_address, 1);
1.40 markus 1237: xfree(originator_address);
1238: xfree(listen_address);
1239: return c;
1240: }
1241:
1.103 deraadt 1242: static Channel *
1.40 markus 1243: client_request_x11(const char *request_type, int rchan)
1244: {
1245: Channel *c = NULL;
1246: char *originator;
1247: int originator_port;
1.67 markus 1248: int sock;
1.40 markus 1249:
1250: if (!options.forward_x11) {
1251: error("Warning: ssh server tried X11 forwarding.");
1252: error("Warning: this is probably a break in attempt by a malicious server.");
1253: return NULL;
1254: }
1255: originator = packet_get_string(NULL);
1256: if (datafellows & SSH_BUG_X11FWD) {
1257: debug2("buggy server: x11 request w/o originator_port");
1258: originator_port = 0;
1259: } else {
1260: originator_port = packet_get_int();
1261: }
1.93 markus 1262: packet_check_eom();
1.40 markus 1263: /* XXX check permission */
1.47 markus 1264: debug("client_request_x11: request from %s %d", originator,
1265: originator_port);
1.67 markus 1266: xfree(originator);
1.40 markus 1267: sock = x11_connect_display();
1.67 markus 1268: if (sock < 0)
1269: return NULL;
1270: c = channel_new("x11",
1271: SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1.110 markus 1272: CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1.82 markus 1273: c->force_drain = 1;
1.40 markus 1274: return c;
1275: }
1276:
1.103 deraadt 1277: static Channel *
1.40 markus 1278: client_request_agent(const char *request_type, int rchan)
1279: {
1280: Channel *c = NULL;
1.67 markus 1281: int sock;
1.40 markus 1282:
1283: if (!options.forward_agent) {
1284: error("Warning: ssh server tried agent forwarding.");
1285: error("Warning: this is probably a break in attempt by a malicious server.");
1286: return NULL;
1287: }
1288: sock = ssh_get_authentication_socket();
1.67 markus 1289: if (sock < 0)
1290: return NULL;
1291: c = channel_new("authentication agent connection",
1292: SSH_CHANNEL_OPEN, sock, sock, -1,
1293: CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1.110 markus 1294: "authentication agent connection", 1);
1.82 markus 1295: c->force_drain = 1;
1.40 markus 1296: return c;
1297: }
1298:
1.22 markus 1299: /* XXXX move to generic input handler */
1.77 itojun 1300: static void
1.94 markus 1301: client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1.22 markus 1302: {
1303: Channel *c = NULL;
1304: char *ctype;
1305: int rchan;
1.102 markus 1306: u_int rmaxpack, rwindow, len;
1.22 markus 1307:
1308: ctype = packet_get_string(&len);
1309: rchan = packet_get_int();
1310: rwindow = packet_get_int();
1311: rmaxpack = packet_get_int();
1312:
1.24 markus 1313: debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1.22 markus 1314: ctype, rchan, rwindow, rmaxpack);
1315:
1.40 markus 1316: if (strcmp(ctype, "forwarded-tcpip") == 0) {
1317: c = client_request_forwarded_tcpip(ctype, rchan);
1318: } else if (strcmp(ctype, "x11") == 0) {
1319: c = client_request_x11(ctype, rchan);
1320: } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1321: c = client_request_agent(ctype, rchan);
1.22 markus 1322: }
1323: /* XXX duplicate : */
1324: if (c != NULL) {
1325: debug("confirm %s", ctype);
1326: c->remote_id = rchan;
1327: c->remote_window = rwindow;
1328: c->remote_maxpacket = rmaxpack;
1.69 markus 1329: if (c->type != SSH_CHANNEL_CONNECTING) {
1330: packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1331: packet_put_int(c->remote_id);
1332: packet_put_int(c->self);
1333: packet_put_int(c->local_window);
1334: packet_put_int(c->local_maxpacket);
1335: packet_send();
1336: }
1.22 markus 1337: } else {
1338: debug("failure %s", ctype);
1339: packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1340: packet_put_int(rchan);
1341: packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1.66 markus 1342: if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1.69 markus 1343: packet_put_cstring("open failed");
1.66 markus 1344: packet_put_cstring("");
1345: }
1.22 markus 1346: packet_send();
1347: }
1348: xfree(ctype);
1349: }
1.77 itojun 1350: static void
1.94 markus 1351: client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1.48 markus 1352: {
1353: Channel *c = NULL;
1354: int id, reply, success = 0;
1355: char *rtype;
1356:
1357: id = packet_get_int();
1358: rtype = packet_get_string(NULL);
1359: reply = packet_get_char();
1360:
1361: debug("client_input_channel_req: channel %d rtype %s reply %d",
1362: id, rtype, reply);
1363:
1364: if (session_ident == -1) {
1365: error("client_input_channel_req: no channel %d", session_ident);
1366: } else if (id != session_ident) {
1367: error("client_input_channel_req: channel %d: wrong channel: %d",
1368: session_ident, id);
1369: }
1370: c = channel_lookup(id);
1371: if (c == NULL) {
1372: error("client_input_channel_req: channel %d: unknown channel", id);
1373: } else if (strcmp(rtype, "exit-status") == 0) {
1374: success = 1;
1375: exit_status = packet_get_int();
1.93 markus 1376: packet_check_eom();
1.48 markus 1377: }
1378: if (reply) {
1379: packet_start(success ?
1380: SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1381: packet_put_int(c->remote_id);
1382: packet_send();
1383: }
1384: xfree(rtype);
1385: }
1.95 markus 1386: static void
1387: client_input_global_request(int type, u_int32_t seq, void *ctxt)
1388: {
1389: char *rtype;
1390: int want_reply;
1391: int success = 0;
1392:
1393: rtype = packet_get_string(NULL);
1394: want_reply = packet_get_char();
1.117 markus 1395: debug("client_input_global_request: rtype %s want_reply %d",
1396: rtype, want_reply);
1.95 markus 1397: if (want_reply) {
1398: packet_start(success ?
1399: SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1400: packet_send();
1401: packet_write_wait();
1402: }
1403: xfree(rtype);
1404: }
1.22 markus 1405:
1.77 itojun 1406: static void
1.49 itojun 1407: client_init_dispatch_20(void)
1.16 markus 1408: {
1.55 markus 1409: dispatch_init(&dispatch_protocol_error);
1.100 markus 1410:
1.16 markus 1411: dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1412: dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1413: dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1414: dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1.22 markus 1415: dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1.16 markus 1416: dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1417: dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1.48 markus 1418: dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1.16 markus 1419: dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1.95 markus 1420: dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1.55 markus 1421:
1422: /* rekeying */
1423: dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1.100 markus 1424:
1425: /* global request reply messages */
1426: dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1427: dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1.16 markus 1428: }
1.77 itojun 1429: static void
1.49 itojun 1430: client_init_dispatch_13(void)
1.15 markus 1431: {
1432: dispatch_init(NULL);
1433: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1434: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1435: dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1436: dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1437: dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1438: dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1439: dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1440: dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1441: dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1.39 markus 1442:
1443: dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1.115 markus 1444: &client_input_agent_open : &deny_input_open);
1.39 markus 1445: dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1446: &x11_input_open : &deny_input_open);
1.15 markus 1447: }
1.77 itojun 1448: static void
1.49 itojun 1449: client_init_dispatch_15(void)
1.15 markus 1450: {
1451: client_init_dispatch_13();
1452: dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1453: dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1454: }
1.79 stevesk 1455: static void
1.49 itojun 1456: client_init_dispatch(void)
1.15 markus 1457: {
1.16 markus 1458: if (compat20)
1459: client_init_dispatch_20();
1460: else if (compat13)
1.15 markus 1461: client_init_dispatch_13();
1462: else
1463: client_init_dispatch_15();
1.113 markus 1464: }
1465:
1466: /* client specific fatal cleanup */
1467: void
1.114 markus 1468: cleanup_exit(int i)
1.113 markus 1469: {
1470: leave_raw_mode();
1471: leave_non_blocking();
1.114 markus 1472: _exit(i);
1.1 deraadt 1473: }
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