1 /***************************************************************************
2 * nmap_tty.cc -- Handles runtime interaction with Nmap, so you can *
3 * increase verbosity/debugging or obtain a status line upon request. *
4 * *
5 ***********************IMPORTANT NMAP LICENSE TERMS************************
6 * *
7 * The Nmap Security Scanner is (C) 1996-2020 Insecure.Com LLC ("The Nmap *
8 * Project"). Nmap is also a registered trademark of the Nmap Project. *
9 * *
10 * This program is distributed under the terms of the Nmap Public Source *
11 * License (NPSL). The exact license text applying to a particular Nmap *
12 * release or source code control revision is contained in the LICENSE *
13 * file distributed with that version of Nmap or source code control *
14 * revision. More Nmap copyright/legal information is available from *
15 * https://nmap.org/book/man-legal.html, and further information on the *
16 * NPSL license itself can be found at https://nmap.org/npsl. This header *
17 * summarizes some key points from the Nmap license, but is no substitute *
18 * for the actual license text. *
19 * *
20 * Nmap is generally free for end users to download and use themselves, *
21 * including commercial use. It is available from https://nmap.org. *
22 * *
23 * The Nmap license generally prohibits companies from using and *
24 * redistributing Nmap in commercial products, but we sell a special Nmap *
25 * OEM Edition with a more permissive license and special features for *
26 * this purpose. See https://nmap.org/oem *
27 * *
28 * If you have received a written Nmap license agreement or contract *
29 * stating terms other than these (such as an Nmap OEM license), you may *
30 * choose to use and redistribute Nmap under those terms instead. *
31 * *
32 * The official Nmap Windows builds include the Npcap software *
33 * (https://npcap.org) for packet capture and transmission. It is under *
34 * separate license terms which forbid redistribution without special *
35 * permission. So the official Nmap Windows builds may not be *
36 * redistributed without special permission (such as an Nmap OEM *
37 * license). *
38 * *
39 * Source is provided to this software because we believe users have a *
40 * right to know exactly what a program is going to do before they run it. *
41 * This also allows you to audit the software for security holes. *
42 * *
43 * Source code also allows you to port Nmap to new platforms, fix bugs, *
44 * and add new features. You are highly encouraged to submit your *
45 * changes as a Github PR or by email to the dev@nmap.org mailing list *
46 * for possible incorporation into the main distribution. Unless you *
47 * specify otherwise, it is understood that you are offering us very *
48 * broad rights to use your submissions as described in the Nmap Public *
49 * Source License Contributor Agreement. This is important because we *
50 * fund the project by selling licenses with various terms, and also *
51 * because the inability to relicense code has caused devastating *
52 * problems for other Free Software projects (such as KDE and NASM). *
53 * *
54 * The free version of Nmap is distributed in the hope that it will be *
55 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty of *
56 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Warranties, *
57 * indemnification and commercial support are all available through the *
58 * Npcap OEM program--see https://nmap.org/oem. *
59 * *
60 ***************************************************************************/
61
62 #ifndef WIN32
63 #include "nmap_config.h"
64 #endif
65
66 #include "nmap.h"
67
68 #include <sys/types.h>
69 #if HAVE_SYS_STAT_H
70 #include <sys/stat.h>
71 #endif
72 #if HAVE_FCNTL_H
73 #include <fcntl.h>
74 #endif
75 #if HAVE_TERMIOS_H
76 #include <termios.h>
77 #endif
78 #if HAVE_UNISTD_H
79 #include <unistd.h>
80 #endif
81 #include <stdlib.h>
82
83 #if TIME_WITH_SYS_TIME
84 # include <sys/time.h>
85 # include <time.h>
86 #else
87 # if HAVE_SYS_TIME_H
88 # include <sys/time.h>
89 # else
90 # include <time.h>
91 # endif
92 #endif
93
94 #include "nmap_tty.h"
95 #include "NmapOps.h"
96
97 extern NmapOps o;
98
99 #ifdef WIN32
100 #include <conio.h>
101
102 // Microsoft's runtime makes this fairly simple. :)
tty_init()103 void tty_init() { return; }
tty_getchar()104 static int tty_getchar() { return _kbhit() ? _getch() : -1; }
tty_done()105 static void tty_done() { return; }
106
tty_flush(void)107 static void tty_flush(void)
108 {
109 static HANDLE stdinput = GetStdHandle(STD_INPUT_HANDLE);
110
111 FlushConsoleInputBuffer(stdinput);
112 }
113
114 #else //!win32
115 #include <signal.h>
116 #if !defined(O_NONBLOCK) && defined(O_NDELAY)
117 #define O_NONBLOCK O_NDELAY
118 #endif
119
120 #ifdef __CYGWIN32__
121 #include <string.h>
122 #include <sys/socket.h>
123 #ifndef __CYGWIN__
124 extern int tcgetattr(int fd, struct termios *termios_p);
125 extern int tcsetattr(int fd, int actions, struct termios *termios_p);
126 #endif
127 #endif
128
129 static int tty_fd = 0;
130 static struct termios saved_ti;
131
tty_getchar()132 static int tty_getchar()
133 {
134 int c, numChars;
135 #ifdef __CYGWIN32__
136 fd_set set;
137 struct timeval tv;
138 #endif
139
140 if (tty_fd && tcgetpgrp(tty_fd) == getpgrp()) {
141
142 // This is so that when the terminal has been disconnected, it will be
143 // reconnected when possible. If it slows things down, just remove it
144 // tty_init();
145
146 #ifdef __CYGWIN32__
147 FD_ZERO(&set); FD_SET(tty_fd, &set);
148 tv.tv_sec = 0; tv.tv_usec = 0;
149 if (select(tty_fd + 1, &set, NULL, NULL, &tv) <= 0)
150 return -1;
151 #endif
152 c = 0;
153 numChars = read(tty_fd, &c, 1);
154 if (numChars > 0) return c;
155 }
156
157 return -1;
158 }
159
tty_done()160 static void tty_done()
161 {
162 if (!tty_fd) return;
163
164 tcsetattr(tty_fd, TCSANOW, &saved_ti);
165
166 close(tty_fd);
167 tty_fd = 0;
168 }
169
tty_flush(void)170 static void tty_flush(void)
171 {
172 /* we don't need to test for tty_fd==0 here because
173 * this isn't called unless we succeeded
174 */
175
176 tcflush(tty_fd, TCIFLUSH);
177 }
178
install_handler(int signo,void (* handler)(int signo))179 static void install_handler(int signo, void (*handler) (int signo))
180 {
181 struct sigaction sa;
182 sa.sa_handler = handler;
183 sigfillset(&sa.sa_mask); /* block all signals during handler execution */
184 sa.sa_flags = 0;
185 sigaction(signo, &sa, NULL);
186 }
187
shutdown_clean(int signo)188 static void shutdown_clean(int signo)
189 {
190 sigset_t set;
191
192 /* We reinstall the default handler and call tty_done */
193 install_handler(signo, SIG_DFL);
194 tty_done();
195
196 /* Unblock signo and raise it (thus allowing the default handler to occur) */
197 sigemptyset(&set);
198 sigaddset(&set, signo);
199 sigprocmask(SIG_UNBLOCK, &set, NULL);
200 raise(signo); /* This _should_ kill us */
201 _exit(EXIT_FAILURE); /* If it does not */
202 }
203
install_all_handlers()204 static void install_all_handlers() {
205 install_handler(SIGINT, shutdown_clean);
206 install_handler(SIGTERM, shutdown_clean);
207 install_handler(SIGQUIT, shutdown_clean);
208 }
209
210 /*
211 * Initializes the terminal for unbuffered non-blocking input. Also
212 * registers tty_done() via atexit(). You need to call this before
213 * you ever call keyWasPressed().
214 */
tty_init()215 void tty_init()
216 {
217 struct termios ti;
218
219 if(o.noninteractive)
220 return;
221
222 install_all_handlers();
223
224 if (tty_fd)
225 return;
226
227 if ((tty_fd = open("/dev/tty", O_RDONLY | O_NONBLOCK)) < 0) return;
228
229 #ifndef __CYGWIN32__
230 if (tcgetpgrp(tty_fd) != getpgrp()) {
231 close(tty_fd); return;
232 }
233 #endif
234
235 tcgetattr(tty_fd, &ti);
236 saved_ti = ti;
237 ti.c_lflag &= ~(ICANON | ECHO);
238 ti.c_cc[VMIN] = 1;
239 ti.c_cc[VTIME] = 0;
240 tcsetattr(tty_fd, TCSANOW, &ti);
241
242 atexit(tty_done);
243 }
244
245 #endif //!win32
246
247 /* Catches all of the predefined
248 keypresses and interpret them, and it will also tell you if you
249 should print anything. A value of true being returned means a
250 nonstandard key has been pressed and the calling method should
251 print a status message */
keyWasPressed()252 bool keyWasPressed()
253 {
254 /* Where we keep the automatic stats printing schedule. */
255 static struct timeval stats_time = { 0 };
256 int c;
257
258 if (o.noninteractive)
259 return false;
260
261 if ((c = tty_getchar()) >= 0) {
262 tty_flush(); /* flush input queue */
263
264 // printf("You pressed key '%c'!\n", c);
265 if (c == 'v') {
266 if (o.verbose < 10) o.verbose++;
267 log_write(LOG_STDOUT, "Verbosity Increased to %d.\n", o.verbose);
268 } else if (c == 'V') {
269 if (o.verbose > 0) o.verbose--;
270 log_write(LOG_STDOUT, "Verbosity Decreased to %d.\n", o.verbose);
271 } else if (c == 'd') {
272 if (o.debugging < 10) o.debugging++;
273 log_write(LOG_STDOUT, "Debugging Increased to %d.\n", o.debugging);
274 } else if (c == 'D') {
275 if (o.debugging > 0) o.debugging--;
276 log_write(LOG_STDOUT, "Debugging Decreased to %d.\n", o.debugging);
277 } else if (c == 'p') {
278 o.setPacketTrace(true);
279 log_write(LOG_STDOUT, "Packet Tracing enabled.\n");
280 } else if (c == 'P') {
281 o.setPacketTrace(false);
282 log_write(LOG_STDOUT, "Packet Tracing disabled.\n");
283 } else if (c == '?') {
284 log_write(LOG_STDOUT,
285 "Interactive keyboard commands:\n"
286 "? Display this information\n"
287 "v/V Increase/decrease verbosity\n"
288 "d/D Increase/decrease debugging\n"
289 "p/P Enable/disable packet tracing\n"
290 "anything else Print status\n"
291 "More help: https://nmap.org/book/man-runtime-interaction.html\n");
292 } else {
293 printStatusMessage();
294 return true;
295 }
296 }
297
298 /* Check if we need to print a status update according to the --stats-every
299 option. */
300 if (o.stats_interval != 0.0) {
301 struct timeval now;
302
303 gettimeofday(&now, NULL);
304 if (stats_time.tv_sec == 0) {
305 /* Initialize the scheduled stats time. */
306 stats_time = *o.getStartTime();
307 TIMEVAL_ADD(stats_time, stats_time, (time_t) (o.stats_interval * 1000000));
308 }
309
310 if (TIMEVAL_AFTER(now, stats_time)) {
311 /* Advance to the next print time. */
312 TIMEVAL_ADD(stats_time, stats_time, (time_t) (o.stats_interval * 1000000));
313 /* If it's still in the past, catch it up to the present,
314 * plus half a second to avoid double-printing without any progress. */
315 if (TIMEVAL_AFTER(now, stats_time))
316 TIMEVAL_MSEC_ADD(stats_time, now, 500);
317 printStatusMessage();
318 /* Instruct the caller to print status too. */
319 return true;
320 }
321 }
322
323 return false;
324 }
325