7901d653 |
1 | --- ../mosh/src/frontend/mosh.cc 2016-04-29 00:42:24.837700203 +1000 |
2 | +++ ./src/frontend/mosh.cc 2016-04-29 00:40:13.346294286 +1000 |
21accda0 |
3 | @@ -0,0 +1,519 @@ |
7901d653 |
4 | +// Mosh: the mobile shell |
5 | +// Copyright 2012 Keith Winstein |
6 | +// |
7 | +// This program is free software: you can redistribute it and/or modify |
8 | +// it under the terms of the GNU General Public License as published by |
9 | +// the Free Software Foundation, either version 3 of the License, or |
10 | +// (at your option) any later version. |
11 | +// |
12 | +// This program is distributed in the hope that it will be useful, |
13 | +// but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
15 | +// GNU General Public License for more details. |
16 | +// |
17 | +// You should have received a copy of the GNU General Public License |
18 | +// along with this program. If not, see <http://www.gnu.org/licenses/>. |
19 | + |
20 | +#include "config.h" |
21 | +#include <limits.h> |
22 | +#include <unistd.h> |
23 | +#include <stdlib.h> |
24 | +#include <stdarg.h> |
25 | +#include <string.h> |
26 | +#include <vector> |
27 | +#include <map> |
28 | +#include <stdio.h> |
29 | +#include <string> |
30 | +#include <sys/socket.h> |
31 | +#include <getopt.h> |
32 | +#include <arpa/inet.h> |
33 | +#include <netdb.h> |
34 | +#include <signal.h> |
35 | +#include <errno.h> |
36 | +#include <sys/ioctl.h> |
37 | +#include <sys/types.h> |
38 | +#include <sys/wait.h> |
39 | +#include <termios.h> |
40 | +#if HAVE_PTY_H |
41 | +#include <pty.h> |
42 | +#elif HAVE_UTIL_H |
43 | +#include <util.h> |
44 | +#endif |
45 | + |
46 | +#if OPENPTY_IN_LIBUTIL |
47 | +#include <libutil.h> |
48 | +#endif |
49 | + |
7901d653 |
50 | +#if !HAVE_GETLINE |
51 | +ssize_t getline( char ** restrict linep, |
52 | + size_t * restrict linecapp, |
53 | + FILE * restrict stream ) { |
54 | + size_t num_read = 0; |
55 | + if ( !linep || !linecapp ) { |
56 | + errno = EINVAL; |
57 | + return -1; |
58 | + } |
59 | + if ( !*linep ) { |
60 | + *linecapp = 0; |
61 | + } |
62 | + while ( 1 ) { |
63 | + int ch = getc( stream ); |
64 | + if ( ch == EOF ) { |
65 | + return num_read ? (ssize_t)num_read : -1; |
66 | + } |
67 | + if ( num_read + 1 >= *linecapp ) { |
68 | + char *new_line = *linep; |
69 | + size_t new_linecap = *linecapp; |
70 | + if ( *linecapp > SSIZE_MAX - 4096 ) { |
71 | + errno = EOVERFLOW; |
72 | + return -1; |
73 | + } |
74 | + new_linecap += 4096; |
75 | + new_line = (char *)realloc( new_line, new_linecap ); |
76 | + if ( !new_line ) { |
77 | + return -1; |
78 | + } |
79 | + *linecapp = new_linecap; |
80 | + *linep = new_line; |
81 | + } |
82 | + (*linep)[num_read++] = ch; |
83 | + // so that we can safely return at any time, |
84 | + (*linep)[num_read] = '\0'; |
85 | + if (ch == '\n') { |
86 | + return num_read; |
87 | + } |
88 | + } |
89 | + return -1; |
90 | +} |
91 | +#endif |
92 | + |
93 | +using namespace std; |
94 | + |
95 | +inline string shell_quote_string( const string &x ) |
96 | +{ |
97 | + string result = "'"; |
98 | + string rest = x; |
99 | + while ( rest.size() ) { |
100 | + size_t good_part = rest.find( "'" ); |
101 | + result += rest.substr( 0, good_part ); |
102 | + if ( good_part != string::npos ) { |
103 | + result += "'\\''"; |
104 | + rest = rest.substr( good_part + 1 ); |
105 | + } else { |
106 | + break; |
107 | + } |
108 | + } |
109 | + return result + "'"; |
110 | +} |
111 | + |
112 | +template <typename SequenceT> |
113 | +inline string shell_quote( const SequenceT &sequence ) |
114 | +{ |
115 | + string result; |
116 | + for ( typename SequenceT::const_iterator i = sequence.begin(); |
117 | + i != sequence.end(); |
118 | + i++ ) { |
119 | + result += shell_quote_string( *i ) + " "; |
120 | + } |
121 | + return result.substr( 0, result.size() - 1 ); |
122 | +} |
123 | + |
124 | +void die( const char *format, ... ) { |
125 | + va_list args; |
126 | + va_start( args, format ); |
127 | + vfprintf( stderr, format, args ); |
128 | + va_end( args ); |
129 | + fprintf( stderr, "\n" ); |
130 | + exit( 255 ); |
131 | +} |
132 | + |
133 | +static const char *usage_format = |
134 | +"Usage: %s [options] [--] [user@]host [command...]\n" |
135 | +" --client=PATH mosh client on local machine\n" |
136 | +" (default: mosh-client)\n" |
137 | +" --server=PATH mosh server on remote machine\n" |
138 | +" (default: mosh-server)\n" |
139 | +"\n" |
140 | +" --predict=adaptive local echo for slower links [default]\n" |
141 | +"-a --predict=always use local echo even on fast links\n" |
142 | +"-n --predict=never never use local echo\n" |
143 | +"\n" |
144 | +"-p NUM --port=NUM server-side UDP port\n" |
145 | +"\n" |
146 | +"-P NUM --ssh-port=NUM ssh server port\n" |
147 | +" (default: let the ssh command choose)\n" |
148 | +"\n" |
149 | +" --ssh=COMMAND ssh command to run when setting up session\n" |
150 | +" (example: \"ssh -p 2222\")\n" |
151 | +" (default: \"ssh\")\n" |
152 | +"\n" |
153 | +" --help this message\n" |
154 | +" --version version and copyright information\n" |
155 | +"\n" |
156 | +"Please report bugs to mosh-devel@mit.edu.\n" |
157 | +"Mosh home page: http://mosh.mit.edu"; |
158 | + |
159 | +static const char *version_format = |
160 | +"mosh %s\n" |
161 | +"Copyright 2012 Keith Winstein <mosh-devel@mit.edu>\n" |
162 | +"License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.\n" |
163 | +"This is free software: you are free to change and redistribute it.\n" |
164 | +"There is NO WARRANTY, to the extent permitted by law."; |
165 | + |
166 | +static const char *key_valid_char_set = |
167 | +"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789/+"; |
168 | + |
169 | +static char *argv0; |
170 | + |
171 | +void predict_check( const string &predict, bool env_set ) |
172 | +{ |
173 | + if ( predict != "adaptive" && |
174 | + predict != "always" && |
175 | + predict != "never" ) { |
176 | + fprintf( stderr, "%s: Unknown mode \"%s\"%s.\n", argv0, predict.c_str(), |
177 | + env_set ? " (MOSH_PREDICTION_DISPLAY in environment)" : "" ); |
178 | + die( usage_format, argv0 ); |
179 | + } |
180 | +} |
181 | + |
182 | +void cat( int ifd, int ofd ) |
183 | +{ |
184 | + char buf[4096]; |
185 | + ssize_t n; |
186 | + while ( 1 ) { |
187 | + n = read( ifd, buf, sizeof( buf ) ); |
188 | + if ( n==-1 ) { |
189 | + if (errno == EINTR ) { |
190 | + continue; |
191 | + } |
192 | + break; |
193 | + } |
194 | + if ( n==0 ) { |
195 | + break; |
196 | + } |
197 | + n = write( ofd, buf, n ); |
198 | + if ( n==-1 ) { |
199 | + break; |
200 | + } |
201 | + } |
202 | +} |
203 | + |
204 | +bool valid_port(string port) { |
205 | + if ( port.size() ) { |
206 | + return port.find_first_not_of( "0123456789" ) == string::npos && |
207 | + atoi( port.c_str() ) > 0 && |
208 | + atoi( port.c_str() ) <= 65535; |
209 | + } |
210 | + return true; // consider no port to be the default value |
211 | +} |
212 | + |
213 | +int main( int argc, char *argv[] ) |
214 | +{ |
215 | + argv0 = argv[0]; |
216 | + string client = "mosh-client"; |
217 | + string server = "mosh-server"; |
218 | + string ssh = "ssh"; |
219 | + string predict, port_request, ssh_port; |
220 | + int help=0, version=0, fake_proxy=0; |
221 | + |
222 | + static struct option long_options[] = |
223 | + { |
224 | + { "client", required_argument, 0, 'c' }, |
225 | + { "server", required_argument, 0, 's' }, |
226 | + { "predict", required_argument, 0, 'r' }, |
227 | + { "port", required_argument, 0, 'p' }, |
228 | + { "ssh-port", required_argument, 0, 'P' }, |
229 | + { "ssh", required_argument, 0, 'S' }, |
230 | + { "help", no_argument, &help, 1 }, |
231 | + { "version", no_argument, &version, 1 }, |
232 | + { "fake-proxy!", no_argument, &fake_proxy, 1 }, |
233 | + { 0, 0, 0, 0 } |
234 | + }; |
235 | + while ( 1 ) { |
236 | + int option_index = 0; |
237 | + int c = getopt_long( argc, argv, "anp:P:", |
238 | + long_options, &option_index ); |
239 | + if ( c == -1 ) { |
240 | + break; |
241 | + } |
242 | + |
243 | + switch ( c ) { |
244 | + case 0: |
245 | + // flag has been set |
246 | + break; |
247 | + case 'c': |
248 | + client = optarg; |
249 | + break; |
250 | + case 's': |
251 | + server = optarg; |
252 | + break; |
253 | + case 'r': |
254 | + predict = optarg; |
255 | + break; |
256 | + case 'p': |
257 | + port_request = optarg; |
258 | + break; |
259 | + case 'P': |
260 | + ssh_port = optarg; |
261 | + break; |
262 | + case 'S': |
263 | + ssh = optarg; |
264 | + break; |
265 | + case 'a': |
266 | + predict = "always"; |
267 | + break; |
268 | + case 'n': |
269 | + predict = "never"; |
270 | + break; |
271 | + default: |
272 | + die( usage_format, argv[0] ); |
273 | + } |
274 | + } |
275 | + |
276 | + if ( help ) { |
277 | + die( usage_format, argv[0] ); |
278 | + } |
279 | + if ( version ) { |
280 | + die( version_format, PACKAGE_VERSION ); |
281 | + } |
282 | + |
283 | + if ( predict.size() ) { |
284 | + predict_check( predict, 0 ); |
285 | + } else if ( getenv( "MOSH_PREDICTION_DELAY" ) ) { |
286 | + predict = getenv( "MOSH_PREDICTION_DELAY" ); |
287 | + predict_check( predict, 1 ); |
288 | + } else { |
289 | + predict = "adaptive"; |
290 | + predict_check( predict, 0 ); |
291 | + } |
292 | + |
293 | + if(!valid_port(port_request)) { |
294 | + die( "%s: Server-side port (%s) must be within valid range [0..65535].", |
295 | + argv[0], |
296 | + port_request.c_str() ); |
297 | + } |
298 | + |
299 | + if(!valid_port(ssh_port)) { |
300 | + die( "%s: SSH port (%s) must be within valid range [0..65535].", |
301 | + argv[0], |
302 | + ssh_port.c_str() ); |
303 | + } |
304 | + |
305 | + unsetenv( "MOSH_PREDICTION_DISPLAY" ); |
306 | + |
307 | + if ( fake_proxy ) { |
308 | + string host = argv[optind++]; |
309 | + string port = argv[optind++]; |
310 | + |
311 | + int sockfd = -1; |
312 | + struct addrinfo hints, *servinfo, *p; |
313 | + int rv; |
314 | + |
315 | + memset( &hints, 0, sizeof( hints ) ); |
316 | + hints.ai_socktype = SOCK_STREAM; |
317 | + |
318 | + if ( ( rv = getaddrinfo( host.c_str(), |
319 | + port.c_str(), |
320 | + &hints, |
321 | + &servinfo ) ) != 0 ) { |
322 | + die( "%s: Could not resolve hostname %s: getaddrinfo: %s", |
323 | + argv[0], |
324 | + host.c_str(), |
325 | + gai_strerror( rv ) ); |
326 | + } |
327 | + |
328 | + int try_family = AF_INET; |
329 | + // loop through all the results and connect to the first we can |
330 | + for ( p = servinfo; p != NULL || try_family == AF_INET; p = p->ai_next ) { |
331 | + if(p == NULL && try_family == AF_INET) { // start over and try AF_INET6 |
332 | + p = servinfo; |
333 | + try_family = AF_INET6; |
334 | + } |
335 | + if(p == NULL) { |
336 | + break; // servinfo == NULL |
337 | + } |
338 | + |
339 | + if(p->ai_family != try_family) { |
340 | + continue; |
341 | + } |
342 | + |
343 | + if ( ( sockfd = socket( p->ai_family, SOCK_STREAM, IPPROTO_TCP ) ) == -1 ) { |
344 | + continue; |
345 | + } |
346 | + |
347 | + if ( connect( sockfd, p->ai_addr, p->ai_addrlen ) == -1 ) { |
348 | + close( sockfd ); |
349 | + continue; |
350 | + } |
351 | + |
352 | + char host[NI_MAXHOST], service[NI_MAXSERV]; |
353 | + if ( getnameinfo( p->ai_addr, p->ai_addrlen, |
354 | + host, NI_MAXHOST, |
355 | + service, NI_MAXSERV, |
356 | + NI_NUMERICSERV | NI_NUMERICHOST ) == -1 ) { |
357 | + die( "Couldn't get host name info" ); |
358 | + } |
359 | + |
360 | + fprintf( stderr, "MOSH IP %s\n", host ); |
361 | + break; // if we get here, we must have connected successfully |
362 | + } |
363 | + |
364 | + if ( p == NULL ) { |
365 | + // looped off the end of the list with no connection |
366 | + die( "%s: failed to connect to host %s port %s", |
367 | + argv[0], host.c_str(), port.c_str() ); |
368 | + } |
369 | + |
370 | + freeaddrinfo( servinfo ); // all done with this structure |
371 | + |
372 | + int pid = fork(); |
373 | + if ( pid == -1 ) { |
374 | + die( "%s: fork: %d", argv[0], errno ); |
375 | + } |
376 | + if ( pid == 0 ) { |
377 | + cat( sockfd, 1 ); |
378 | + shutdown( sockfd, 0 ); |
379 | + exit( 0 ); |
380 | + } |
381 | + signal( SIGHUP, SIG_IGN ); |
382 | + cat( 0, sockfd ); |
383 | + shutdown( sockfd, 1 ); |
384 | + waitpid( pid, NULL, 0 ); |
385 | + exit( 0 ); |
386 | + } |
387 | + |
388 | + if ( argc - optind < 1 ) { |
389 | + die( usage_format, argv[0] ); |
390 | + } |
391 | + |
392 | + string userhost = argv[optind++]; |
393 | + char **command = &argv[optind]; |
394 | + int commands = argc - optind; |
395 | + |
396 | + string color_invocation = client + " -c"; |
397 | + FILE *color_file = popen( color_invocation.c_str(), "r" ); |
398 | + if ( !color_file ) { |
399 | + die( "%s: popen: %d", argv[0], errno ); |
400 | + } |
401 | + char *buf = NULL; |
402 | + size_t buf_sz = 0; |
403 | + ssize_t n; |
404 | + if ( ( n = getline( &buf, &buf_sz, color_file ) ) < 0 ) { |
405 | + die( "%s: Can't count colors: %d", argv[0], errno ); |
406 | + } |
407 | + string colors = string( buf, n ); |
408 | + pclose( color_file ); |
409 | + |
410 | + if ( !colors.size() || |
411 | + colors.find_first_not_of( "0123456789" ) != string::npos || |
412 | + atoi( colors.c_str() ) < 0 ) { |
413 | + colors = "0"; |
414 | + } |
415 | + |
416 | + int pty, pty_slave; |
417 | + struct winsize ws; |
418 | + if ( ioctl( 0, TIOCGWINSZ, &ws ) == -1 ) { |
419 | + die( "%s: ioctl: %d", argv[0], errno ); |
420 | + } |
421 | + |
422 | + if ( openpty( &pty, &pty_slave, NULL, NULL, &ws ) == -1 ) { |
423 | + die( "%s: openpty: %d", argv[0], errno ); |
424 | + } |
425 | + |
426 | + int pid = fork(); |
427 | + if ( pid == -1 ) { |
428 | + die( "%s: fork: %d", argv[0], errno ); |
429 | + } |
430 | + if ( pid == 0 ) { |
431 | + close( pty ); |
432 | + if ( -1 == dup2( pty_slave, 1 ) || |
433 | + -1 == dup2( pty_slave, 2 ) ) { |
434 | + die( "%s: dup2: %d", argv[0], errno ); |
435 | + } |
436 | + close( pty_slave ); |
437 | + |
438 | + vector<string> server_args; |
439 | + server_args.push_back( "new" ); |
440 | + server_args.push_back( "-s" ); |
441 | + server_args.push_back( "-c" ); |
442 | + server_args.push_back( colors ); |
443 | + if ( port_request.size() ) { |
444 | + server_args.push_back( "-p" ); |
445 | + server_args.push_back( port_request ); |
446 | + } |
447 | + if ( commands ) { |
448 | + server_args.insert( server_args.end(), command, command + commands ); |
449 | + } |
450 | + string quoted_self = shell_quote_string( string( argv[0] ) ); |
451 | + string quoted_server_args = shell_quote( server_args ); |
452 | + fflush( stdout ); |
453 | + |
454 | + string proxy_arg = "ProxyCommand=" + quoted_self + " --fake-proxy -- %h %p"; |
455 | + string ssh_remote_command = server + " " + quoted_server_args; |
456 | + |
457 | + vector<string> ssh_args; |
458 | + ssh_args.push_back( "-S" ); |
459 | + ssh_args.push_back( "none" ); |
460 | + ssh_args.push_back( "-o" ); |
461 | + ssh_args.push_back( proxy_arg ); |
462 | + ssh_args.push_back( "-t" ); |
463 | + ssh_args.push_back( userhost ); |
464 | + if ( ssh_port.size() ) { |
465 | + ssh_args.push_back( "-p" ); |
466 | + ssh_args.push_back( ssh_port ); |
467 | + } |
468 | + ssh_args.push_back( "--" ); |
469 | + ssh_args.push_back( ssh_remote_command ); |
470 | + |
471 | + string ssh_exec_string = ssh + " " + shell_quote( ssh_args ); |
472 | + |
473 | + int ret = execlp( "sh", "sh", "-c", ssh_exec_string.c_str(), (char *)NULL ); |
474 | + if ( ret == -1 ) { |
475 | + die( "Cannot exec ssh: %d", errno ); |
476 | + } |
477 | + } |
478 | + |
479 | + close( pty_slave ); |
480 | + string ip, port, key; |
481 | + |
482 | + FILE *pty_file = fdopen( pty, "r" ); |
483 | + string line; |
484 | + while ( ( n = getline( &buf, &buf_sz, pty_file ) ) >= 0 ) { |
485 | + line = string( buf, n ); |
486 | + line = line.erase( line.find_last_not_of( "\n" ) ); |
487 | + if ( line.compare( 0, 8, "MOSH IP " ) == 0 ) { |
488 | + size_t ip_end = line.find_last_not_of( " \t\n\r" ); |
489 | + if ( ip_end != string::npos && ip_end >= 8 ) { |
490 | + ip = line.substr( 8, ip_end + 1 - 8 ); |
491 | + } |
492 | + } else if ( line.compare( 0, 13, "MOSH CONNECT " ) == 0 ) { |
493 | + size_t port_end = line.find_first_not_of( "0123456789", 13 ); |
494 | + if ( port_end != string::npos && port_end >= 13 ) { |
495 | + port = line.substr( 13, port_end - 13 ); |
496 | + } |
497 | + string rest = line.substr( port_end + 1 ); |
498 | + size_t key_end = rest.find_last_not_of( " \t\n\r" ); |
499 | + size_t key_valid_end = rest.find_last_of( key_valid_char_set ); |
500 | + if ( key_valid_end == key_end && key_end + 1 == 22 ) { |
501 | + key = rest.substr( 0, key_end + 1 ); |
502 | + } |
503 | + break; |
504 | + } else { |
505 | + printf( "%s\n", line.c_str() ); |
506 | + } |
507 | + } |
508 | + waitpid( pid, NULL, 0 ); |
509 | + |
510 | + if ( !ip.size() ) { |
511 | + die( "%s: Did not find remote IP address (is SSH ProxyCommand disabled?).", |
512 | + argv[0] ); |
513 | + } |
514 | + |
515 | + if ( !key.size() || !port.size() ) { |
516 | + die( "%s: Did not find mosh server startup message.", argv[0] ); |
517 | + } |
518 | + |
519 | + setenv( "MOSH_KEY", key.c_str(), 1 ); |
520 | + setenv( "MOSH_PREDICTION_DISPLAY", predict.c_str(), 1 ); |
521 | + execlp( client.c_str(), client.c_str(), ip.c_str(), port.c_str(), (char *)NULL ); |
522 | +} |