xref: /freebsd/usr.bin/tftp/main.c (revision 92570f67c7911126ce742a3dfe1b97046091ed0e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1983, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)main.c	8.1 (Berkeley) 6/6/93";
41 #endif
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 /* Many bug fixes are from Jim Guyton <guyton@rand-unix> */
48 
49 /*
50  * TFTP User Program -- Command Interface.
51  */
52 #include <sys/param.h>
53 #include <sys/file.h>
54 #include <sys/socket.h>
55 #include <sys/stat.h>
56 #include <sys/sysctl.h>
57 
58 #include <netinet/in.h>
59 #include <arpa/inet.h>
60 #include <arpa/tftp.h>
61 
62 #include <ctype.h>
63 #include <err.h>
64 #include <histedit.h>
65 #include <netdb.h>
66 #include <setjmp.h>
67 #include <signal.h>
68 #include <stdbool.h>
69 #include <stddef.h>
70 #include <stdio.h>
71 #include <stdlib.h>
72 #include <string.h>
73 #include <unistd.h>
74 
75 #include "tftp-utils.h"
76 #include "tftp-io.h"
77 #include "tftp-options.h"
78 #include "tftp.h"
79 
80 #define	MAXLINE		(2 * MAXPATHLEN)
81 #define	TIMEOUT		5		/* secs between rexmt's */
82 
83 typedef struct	sockaddr_storage peeraddr;
84 static int	connected;
85 static char	mode[32];
86 static jmp_buf	toplevel;
87 static int	txrx_error;
88 static int	peer;
89 
90 #define	MAX_MARGV	20
91 static int	margc;
92 static char	*margv[MAX_MARGV];
93 
94 int		verbose;
95 static char	*port = NULL;
96 
97 static void	get(int, char **);
98 static void	help(int, char **);
99 static void	intr(int);
100 static void	modecmd(int, char **);
101 static void	put(int, char **);
102 static void	quit(int, char **);
103 static void	setascii(int, char **);
104 static void	setbinary(int, char **);
105 static void	setpeer0(char *, const char *);
106 static void	setpeer(int, char **);
107 static void	settimeoutpacket(int, char **);
108 static void	settimeoutnetwork(int, char **);
109 static void	setdebug(int, char **);
110 static void	setverbose(int, char **);
111 static void	showstatus(int, char **);
112 static void	setblocksize(int, char **);
113 static void	setblocksize2(int, char **);
114 static void	setoptions(int, char **);
115 static void	setrollover(int, char **);
116 static void	setpacketdrop(int, char **);
117 static void	setwindowsize(int, char **);
118 
119 static void command(bool, EditLine *, History *, HistEvent *) __dead2;
120 static const char *command_prompt(void);
121 
122 static void urihandling(char *URI);
123 static void getusage(char *);
124 static void makeargv(char *line);
125 static void putusage(char *);
126 static void settftpmode(const char *);
127 
128 static char	*tail(char *);
129 static const struct cmd *getcmd(const char *);
130 
131 #define HELPINDENT (sizeof("connect"))
132 
133 struct cmd {
134 	const char	*name;
135 	void	(*handler)(int, char **);
136 	const char	*help;
137 };
138 
139 static struct cmd cmdtab[] = {
140 	{ "connect",	setpeer,	"connect to remote tftp"	},
141 	{ "mode",	modecmd,	"set file transfer mode"	},
142 	{ "put",	put,		"send file"			},
143 	{ "get",	get,		"receive file"			},
144 	{ "quit",	quit,		"exit tftp"			},
145 	{ "verbose",	setverbose,	"toggle verbose mode"		},
146 	{ "status",	showstatus,	"show current status"		},
147 	{ "binary",     setbinary,	"set mode to octet"		},
148 	{ "ascii",      setascii,	"set mode to netascii"		},
149 	{ "rexmt",	settimeoutpacket,
150 	  "set per-packet retransmission timeout[-]" },
151 	{ "timeout",	settimeoutnetwork,
152 	  "set total retransmission timeout" },
153 	{ "trace",	setdebug,	"enable 'debug packet'[-]"	},
154 	{ "debug",	setdebug,	"enable verbose output"		},
155 	{ "blocksize",	setblocksize,	"set blocksize[*]"		},
156 	{ "blocksize2",	setblocksize2,	"set blocksize as a power of 2[**]" },
157 	{ "rollover",	setrollover,	"rollover after 64K packets[**]" },
158 	{ "options",	setoptions,
159 	  "enable or disable RFC2347 style options" },
160 	{ "help",	help,		"print help information"	},
161 	{ "packetdrop",	setpacketdrop,	"artificial packetloss feature"	},
162 	{ "windowsize",	setwindowsize,	"set windowsize[*]"		},
163 	{ "?",		help,		"print help information"	},
164 	{ NULL,		NULL,		NULL				}
165 };
166 
167 static struct	modes {
168 	const char *m_name;
169 	const char *m_mode;
170 } modes[] = {
171 	{ "ascii",	"netascii" },
172 	{ "netascii",	"netascii" },
173 	{ "binary",	"octet" },
174 	{ "image",	"octet" },
175 	{ "octet",	"octet" },
176 	{ NULL,		NULL }
177 };
178 
179 int
180 main(int argc, char *argv[])
181 {
182 	HistEvent he;
183 	static EditLine *el;
184 	static History *hist;
185 	bool interactive;
186 
187 	acting_as_client = 1;
188 	peer = -1;
189 	strcpy(mode, "octet");
190 	signal(SIGINT, intr);
191 
192 	interactive = isatty(STDIN_FILENO);
193 	if (interactive) {
194 		el = el_init("tftp", stdin, stdout, stderr);
195 		hist = history_init();
196 		history(hist, &he, H_SETSIZE, 100);
197 		el_set(el, EL_HIST, history, hist);
198 		el_set(el, EL_EDITOR, "emacs");
199 		el_set(el, EL_PROMPT, command_prompt);
200 		el_set(el, EL_SIGNAL, 1);
201 		el_source(el, NULL);
202 	}
203 
204 	if (argc > 1) {
205 		if (setjmp(toplevel) != 0)
206 			exit(txrx_error);
207 
208 		if (strncmp(argv[1], "tftp://", 7) == 0) {
209 			urihandling(argv[1]);
210 			exit(txrx_error);
211 		}
212 
213 		setpeer(argc, argv);
214 	}
215 
216 	if (setjmp(toplevel) != 0) {
217 		if (interactive)
218 			el_reset(el);
219 		(void)putchar('\n');
220 	}
221 
222 	init_options();
223 	command(interactive, el, hist, &he);
224 }
225 
226 /*
227  * RFC3617 handling of TFTP URIs:
228  *
229  *    tftpURI         = "tftp://" host "/" file [ mode ]
230  *    mode            = ";"  "mode=" ( "netascii" / "octet" )
231  *    file            = *( unreserved / escaped )
232  *    host            = <as specified by RFC 2732>
233  *    unreserved      = <as specified in RFC 2396>
234  *    escaped         = <as specified in RFC 2396>
235  *
236  * We are cheating a little bit by allowing any mode as specified in the
237  * modes table defined earlier on in this file and mapping it on the real
238  * mode.
239  */
240 static void
241 urihandling(char *URI)
242 {
243 	char	uri[ARG_MAX];
244 	char	*host = NULL;
245 	char	*path = NULL;
246 	char	*opts = NULL;
247 	const char *tmode = "octet";
248 	char	*s;
249 	char	line[MAXLINE];
250 	int	i;
251 
252 	strlcpy(uri, URI, ARG_MAX);
253 	host = uri + 7;
254 
255 	if ((s = strchr(host, '/')) == NULL) {
256 		fprintf(stderr,
257 		    "Invalid URI: Couldn't find / after hostname\n");
258 		exit(1);
259 	}
260 	*s = '\0';
261 	path = s + 1;
262 
263 	if ((s = strchr(path, ';')) != NULL) {
264 		*s = '\0';
265 		opts = s + 1;
266 
267 		if (strncmp(opts, "mode=", 5) == 0) {
268 			tmode = opts;
269 			tmode += 5;
270 
271 			for (i = 0; modes[i].m_name != NULL; i++) {
272 				if (strcmp(modes[i].m_name, tmode) == 0)
273 					break;
274 			}
275 			if (modes[i].m_name == NULL) {
276 				fprintf(stderr, "Invalid mode: '%s'\n", mode);
277 				exit(1);
278 			}
279 			settftpmode(modes[i].m_mode);
280 		}
281 	} else {
282 		settftpmode("octet");
283 	}
284 
285 	setpeer0(host, NULL);
286 
287 	sprintf(line, "get %s", path);
288 	makeargv(line);
289 	get(margc, margv);
290 }
291 
292 static char    hostname[MAXHOSTNAMELEN];
293 
294 static void
295 setpeer0(char *host, const char *lport)
296 {
297 	struct addrinfo hints, *res0, *res;
298 	int error;
299 	const char *cause = "unknown";
300 
301 	if (connected) {
302 		close(peer);
303 		peer = -1;
304 	}
305 	connected = 0;
306 
307 	memset(&hints, 0, sizeof(hints));
308 	hints.ai_family = PF_UNSPEC;
309 	hints.ai_socktype = SOCK_DGRAM;
310 	hints.ai_protocol = IPPROTO_UDP;
311 	hints.ai_flags = AI_CANONNAME;
312 	if (!lport)
313 		lport = "tftp";
314 	error = getaddrinfo(host, lport, &hints, &res0);
315 	if (error) {
316 		warnx("%s", gai_strerror(error));
317 		return;
318 	}
319 
320 	for (res = res0; res; res = res->ai_next) {
321 		if (res->ai_addrlen > sizeof(peeraddr))
322 			continue;
323 		peer = socket(res->ai_family, res->ai_socktype,
324 			res->ai_protocol);
325 		if (peer < 0) {
326 			cause = "socket";
327 			continue;
328 		}
329 
330 		memset(&peer_sock, 0, sizeof(peer_sock));
331 		peer_sock.ss_family = res->ai_family;
332 		peer_sock.ss_len = res->ai_addrlen;
333 		if (bind(peer, (struct sockaddr *)&peer_sock, peer_sock.ss_len) < 0) {
334 			cause = "bind";
335 			close(peer);
336 			peer = -1;
337 			continue;
338 		}
339 
340 		break;
341 	}
342 
343 	if (peer < 0)
344 		warn("%s", cause);
345 	else {
346 		/* res->ai_addr <= sizeof(peeraddr) is guaranteed */
347 		memcpy(&peer_sock, res->ai_addr, res->ai_addrlen);
348 		if (res->ai_canonname) {
349 			(void) strlcpy(hostname, res->ai_canonname,
350 				sizeof(hostname));
351 		} else
352 			(void) strlcpy(hostname, host, sizeof(hostname));
353 		connected = 1;
354 	}
355 
356 	freeaddrinfo(res0);
357 }
358 
359 static void
360 setpeer(int argc, char *argv[])
361 {
362 	char	line[MAXLINE];
363 
364 	if (argc < 2) {
365 		strcpy(line, "Connect ");
366 		printf("(to) ");
367 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
368 		makeargv(line);
369 		argc = margc;
370 		argv = margv;
371 	}
372 	if ((argc < 2) || (argc > 3)) {
373 		printf("usage: %s [host [port]]\n", argv[0]);
374 		return;
375 	}
376 	if (argc == 3) {
377 		port = argv[2];
378 		setpeer0(argv[1], argv[2]);
379 	} else
380 		setpeer0(argv[1], NULL);
381 }
382 
383 static void
384 modecmd(int argc, char *argv[])
385 {
386 	struct modes *p;
387 	const char *sep;
388 
389 	if (argc < 2) {
390 		printf("Using %s mode to transfer files.\n", mode);
391 		return;
392 	}
393 	if (argc == 2) {
394 		for (p = modes; p->m_name; p++)
395 			if (strcmp(argv[1], p->m_name) == 0)
396 				break;
397 		if (p->m_name) {
398 			settftpmode(p->m_mode);
399 			return;
400 		}
401 		printf("%s: unknown mode\n", argv[1]);
402 		/* drop through and print usage message */
403 	}
404 
405 	printf("usage: %s [", argv[0]);
406 	sep = " ";
407 	for (p = modes; p->m_name != NULL; p++) {
408 		printf("%s%s", sep, p->m_name);
409 		if (*sep == ' ')
410 			sep = " | ";
411 	}
412 	printf(" ]\n");
413 	return;
414 }
415 
416 static void
417 setbinary(int argc __unused, char *argv[] __unused)
418 {
419 
420 	settftpmode("octet");
421 }
422 
423 static void
424 setascii(int argc __unused, char *argv[] __unused)
425 {
426 
427 	settftpmode("netascii");
428 }
429 
430 static void
431 settftpmode(const char *newmode)
432 {
433 
434 	strlcpy(mode, newmode, sizeof(mode));
435 	if (verbose)
436 		printf("mode set to %s\n", mode);
437 }
438 
439 
440 /*
441  * Send file(s).
442  */
443 static void
444 put(int argc, char *argv[])
445 {
446 	int	fd;
447 	int	n;
448 	char	*cp, *targ, *path;
449 	char	line[MAXLINE];
450 	struct stat sb;
451 
452 	if (argc < 2) {
453 		strcpy(line, "send ");
454 		printf("(file) ");
455 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
456 		makeargv(line);
457 		argc = margc;
458 		argv = margv;
459 	}
460 	if (argc < 2) {
461 		putusage(argv[0]);
462 		return;
463 	}
464 	targ = argv[argc - 1];
465 	if (strrchr(argv[argc - 1], ':')) {
466 		char *lcp;
467 
468 		for (n = 1; n < argc - 1; n++)
469 			if (strchr(argv[n], ':')) {
470 				putusage(argv[0]);
471 				return;
472 			}
473 		lcp = argv[argc - 1];
474 		targ = strrchr(lcp, ':');
475 		*targ++ = 0;
476 		if (lcp[0] == '[' && lcp[strlen(lcp) - 1] == ']') {
477 			lcp[strlen(lcp) - 1] = '\0';
478 			lcp++;
479 		}
480 		setpeer0(lcp, NULL);
481 	}
482 	if (!connected) {
483 		printf("No target machine specified.\n");
484 		return;
485 	}
486 	if (argc < 4) {
487 		cp = argc == 2 ? tail(targ) : argv[1];
488 		fd = open(cp, O_RDONLY);
489 		if (fd < 0) {
490 			warn("%s", cp);
491 			return;
492 		}
493 
494 		if (fstat(fd, &sb) < 0) {
495 			warn("%s", cp);
496 			close(fd);
497 			return;
498 		}
499 		options_set_request(OPT_TSIZE, "%ju", (uintmax_t)sb.st_size);
500 
501 		if (verbose)
502 			printf("putting %s to %s:%s [%s]\n",
503 			    cp, hostname, targ, mode);
504 		if (xmitfile(peer, port, fd, targ, mode))
505 			txrx_error = 1;
506 		close(fd);
507 		return;
508 	}
509 				/* this assumes the target is a directory */
510 				/* on a remote unix system.  hmmmm.  */
511 	for (n = 1; n < argc - 1; n++) {
512 		if (asprintf(&path, "%s/%s", targ, tail(argv[n])) < 0)
513 			err(1, "malloc");
514 
515 		fd = open(argv[n], O_RDONLY);
516 		if (fd < 0) {
517 			warn("%s", argv[n]);
518 			free(path);
519 			continue;
520 		}
521 
522 		if (fstat(fd, &sb) < 0) {
523 			warn("%s", argv[n]);
524 			close(fd);
525 			free(path);
526 			continue;
527 		}
528 		options_set_request(OPT_TSIZE, "%ju", (uintmax_t)sb.st_size);
529 
530 		if (verbose)
531 			printf("putting %s to %s:%s [%s]\n",
532 			    argv[n], hostname, path, mode);
533 		if (xmitfile(peer, port, fd, path, mode) != 0)
534 			txrx_error = 1;
535 		close(fd);
536 
537 		free(path);
538 	}
539 }
540 
541 static void
542 putusage(char *s)
543 {
544 
545 	printf("usage: %s file [remotename]\n", s);
546 	printf("       %s file host:remotename\n", s);
547 	printf("       %s file1 file2 ... fileN [[host:]remote-directory]\n", s);
548 }
549 
550 /*
551  * Receive file(s).
552  */
553 static void
554 get(int argc, char *argv[])
555 {
556 	int fd;
557 	int n;
558 	char *cp;
559 	char *src;
560 	char	line[MAXLINE];
561 
562 	if (argc < 2) {
563 		strcpy(line, "get ");
564 		printf("(files) ");
565 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
566 		makeargv(line);
567 		argc = margc;
568 		argv = margv;
569 	}
570 	if (argc < 2) {
571 		getusage(argv[0]);
572 		return;
573 	}
574 	if (!connected) {
575 		for (n = 1; n < argc ; n++)
576 			if (strrchr(argv[n], ':') == 0) {
577 				printf("No remote host specified and "
578 				    "no host given for file '%s'\n", argv[n]);
579 				getusage(argv[0]);
580 				return;
581 			}
582 	}
583 	for (n = 1; n < argc ; n++) {
584 		src = strrchr(argv[n], ':');
585 		if (src == NULL)
586 			src = argv[n];
587 		else {
588 			char *lcp;
589 
590 			*src++ = 0;
591 			lcp = argv[n];
592 			if (lcp[0] == '[' && lcp[strlen(lcp) - 1] == ']') {
593 				lcp[strlen(lcp) - 1] = '\0';
594 				lcp++;
595 			}
596 			setpeer0(lcp, NULL);
597 			if (!connected)
598 				continue;
599 		}
600 		if (argc < 4) {
601 			cp = argc == 3 ? argv[2] : tail(src);
602 			fd = creat(cp, 0644);
603 			if (fd < 0) {
604 				warn("%s", cp);
605 				return;
606 			}
607 			if (verbose)
608 				printf("getting from %s:%s to %s [%s]\n",
609 				    hostname, src, cp, mode);
610 			if (recvfile(peer, port, fd, src, mode) != 0)
611 				txrx_error = 1;
612 			break;
613 		}
614 		cp = tail(src);         /* new .. jdg */
615 		fd = creat(cp, 0644);
616 		if (fd < 0) {
617 			warn("%s", cp);
618 			continue;
619 		}
620 		if (verbose)
621 			printf("getting from %s:%s to %s [%s]\n",
622 			    hostname, src, cp, mode);
623 		if (recvfile(peer, port, fd, src, mode) != 0)
624 			txrx_error = 1;
625 	}
626 }
627 
628 static void
629 getusage(char *s)
630 {
631 
632 	printf("usage: %s file [localname]\n", s);
633 	printf("       %s [host:]file [localname]\n", s);
634 	printf("       %s [host1:]file1 [host2:]file2 ... [hostN:]fileN\n", s);
635 }
636 
637 static void
638 settimeoutpacket(int argc, char *argv[])
639 {
640 	int t;
641 	char	line[MAXLINE];
642 
643 	if (argc < 2) {
644 		strcpy(line, "Packet timeout ");
645 		printf("(value) ");
646 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
647 		makeargv(line);
648 		argc = margc;
649 		argv = margv;
650 	}
651 	if (argc != 2) {
652 		printf("usage: %s value\n", argv[0]);
653 		return;
654 	}
655 	t = atoi(argv[1]);
656 	if (t < 0) {
657 		printf("%s: bad value\n", argv[1]);
658 		return;
659 	}
660 
661 	settimeouts(t, timeoutnetwork, maxtimeouts);
662 }
663 
664 static void
665 settimeoutnetwork(int argc, char *argv[])
666 {
667 	int t;
668 	char	line[MAXLINE];
669 
670 	if (argc < 2) {
671 		strcpy(line, "Network timeout ");
672 		printf("(value) ");
673 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
674 		makeargv(line);
675 		argc = margc;
676 		argv = margv;
677 	}
678 	if (argc != 2) {
679 		printf("usage: %s value\n", argv[0]);
680 		return;
681 	}
682 	t = atoi(argv[1]);
683 	if (t < 0) {
684 		printf("%s: bad value\n", argv[1]);
685 		return;
686 	}
687 
688 	settimeouts(timeoutpacket, t, maxtimeouts);
689 }
690 
691 static void
692 showstatus(int argc __unused, char *argv[] __unused)
693 {
694 
695 	printf("Remote host: %s\n",
696 	    connected ? hostname : "none specified yet");
697 	printf("RFC2347 Options support: %s\n",
698 	    options_rfc_enabled ? "enabled" : "disabled");
699 	printf("Non-RFC defined options support: %s\n",
700 	    options_extra_enabled ? "enabled" : "disabled");
701 	printf("Mode: %s\n", mode);
702 	printf("Verbose: %s\n", verbose ? "on" : "off");
703 	printf("Debug: %s\n", debug_show(debug));
704 	printf("Artificial packetloss: %d in 100 packets\n",
705 	    packetdroppercentage);
706 	printf("Segment size: %d bytes\n", segsize);
707 	printf("Network timeout: %d seconds\n", timeoutpacket);
708 	printf("Maximum network timeout: %d seconds\n", timeoutnetwork);
709 	printf("Maximum timeouts: %d \n", maxtimeouts);
710 }
711 
712 static void
713 intr(int dummy __unused)
714 {
715 
716 	signal(SIGALRM, SIG_IGN);
717 	alarm(0);
718 	longjmp(toplevel, -1);
719 }
720 
721 static char *
722 tail(char *filename)
723 {
724 	char *s;
725 
726 	while (*filename) {
727 		s = strrchr(filename, '/');
728 		if (s == NULL)
729 			break;
730 		if (s[1])
731 			return (s + 1);
732 		*s = '\0';
733 	}
734 	return (filename);
735 }
736 
737 static const char *
738 command_prompt(void)
739 {
740 
741 	return ("tftp> ");
742 }
743 
744 /*
745  * Command parser.
746  */
747 static void
748 command(bool interactive, EditLine *el, History *hist, HistEvent *hep)
749 {
750 	const struct cmd *c;
751 	const char *bp;
752 	char *cp;
753 	int len, num;
754 	char	line[MAXLINE];
755 
756 	for (;;) {
757 		if (interactive) {
758 			if ((bp = el_gets(el, &num)) == NULL || num == 0)
759 				exit(0);
760 			len = MIN(MAXLINE, num);
761 			memcpy(line, bp, len);
762 			line[len - 1] = '\0';
763 			history(hist, hep, H_ENTER, bp);
764 		} else {
765 			line[0] = 0;
766 			if (fgets(line, sizeof line , stdin) == NULL) {
767 				if (feof(stdin)) {
768 					exit(txrx_error);
769 				} else {
770 					continue;
771 				}
772 			}
773 		}
774 		if ((cp = strchr(line, '\n')))
775 			*cp = '\0';
776 		if (line[0] == 0)
777 			continue;
778 		makeargv(line);
779 		if (margc == 0)
780 			continue;
781 		c = getcmd(margv[0]);
782 		if (c == (struct cmd *)-1) {
783 			printf("?Ambiguous command\n");
784 			continue;
785 		}
786 		if (c == NULL) {
787 			printf("?Invalid command\n");
788 			continue;
789 		}
790 		(*c->handler)(margc, margv);
791 	}
792 }
793 
794 static const struct cmd *
795 getcmd(const char *name)
796 {
797 	const char *p, *q;
798 	const struct cmd *c, *found;
799 	ptrdiff_t longest;
800 	int nmatches;
801 
802 	longest = 0;
803 	nmatches = 0;
804 	found = 0;
805 	for (c = cmdtab; (p = c->name) != NULL; c++) {
806 		for (q = name; *q == *p++; q++)
807 			if (*q == '\0')		/* exact match? */
808 				return (c);
809 		if (*q == '\0') {		/* the name was a prefix */
810 			if (q - name > longest) {
811 				longest = q - name;
812 				nmatches = 1;
813 				found = c;
814 			} else if (q - name == longest)
815 				nmatches++;
816 		}
817 	}
818 	if (nmatches > 1)
819 		return ((struct cmd *)-1);
820 	return (found);
821 }
822 
823 /*
824  * Slice a string up into argc/argv.
825  */
826 static void
827 makeargv(char *line)
828 {
829 	char *cp;
830 	char **argp = margv;
831 
832 	margc = 0;
833 	if ((cp = strchr(line, '\n')) != NULL)
834 		*cp = '\0';
835 	for (cp = line; margc < MAX_MARGV - 1 && *cp != '\0';) {
836 		while (isspace(*cp))
837 			cp++;
838 		if (*cp == '\0')
839 			break;
840 		*argp++ = cp;
841 		margc += 1;
842 		while (*cp != '\0' && !isspace(*cp))
843 			cp++;
844 		if (*cp == '\0')
845 			break;
846 		*cp++ = '\0';
847 	}
848 	*argp++ = 0;
849 }
850 
851 static void
852 quit(int argc __unused, char *argv[] __unused)
853 {
854 
855 	exit(txrx_error);
856 }
857 
858 /*
859  * Help command.
860  */
861 static void
862 help(int argc, char *argv[])
863 {
864 	const struct cmd *c;
865 
866 	if (argc == 1) {
867 		printf("Commands may be abbreviated.  Commands are:\n\n");
868 		for (c = cmdtab; c->name; c++)
869 			printf("%-*s\t%s\n", (int)HELPINDENT, c->name, c->help);
870 
871 		printf("\n[-] : You shouldn't use these ones anymore.\n");
872 		printf("[*] : RFC2347 options support required.\n");
873 		printf("[**] : Non-standard RFC2347 option.\n");
874 		return;
875 	}
876 	while (--argc > 0) {
877 		char *arg;
878 		arg = *++argv;
879 		c = getcmd(arg);
880 		if (c == (struct cmd *)-1)
881 			printf("?Ambiguous help command: %s\n", arg);
882 		else if (c == (struct cmd *)0)
883 			printf("?Invalid help command: %s\n", arg);
884 		else
885 			printf("%s\n", c->help);
886 	}
887 }
888 
889 static void
890 setverbose(int argc __unused, char *argv[] __unused)
891 {
892 
893 	verbose = !verbose;
894 	printf("Verbose mode %s.\n", verbose ? "on" : "off");
895 }
896 
897 static void
898 setoptions(int argc, char *argv[])
899 {
900 
901 	if (argc == 2) {
902 		if (strcasecmp(argv[1], "enable") == 0 ||
903 		    strcasecmp(argv[1], "on") == 0) {
904 			options_extra_enabled = 1;
905 			options_rfc_enabled = 1;
906 		}
907 		if (strcasecmp(argv[1], "disable") == 0 ||
908 		    strcasecmp(argv[1], "off") == 0) {
909 			options_extra_enabled = 0;
910 			options_rfc_enabled = 0;
911 		}
912 		if (strcasecmp(argv[1], "extra") == 0)
913 			options_extra_enabled = !options_extra_enabled;
914 	}
915 	printf("Support for RFC2347 style options are now %s.\n",
916 	    options_rfc_enabled ? "enabled" : "disabled");
917 	printf("Support for non-RFC defined options are now %s.\n",
918 	    options_extra_enabled ? "enabled" : "disabled");
919 
920 	printf("\nThe following options are available:\n"
921 	    "\toptions on	: enable support for RFC2347 style options\n"
922 	    "\toptions off	: disable support for RFC2347 style options\n"
923 	    "\toptions extra	: toggle support for non-RFC defined options\n"
924 	);
925 }
926 
927 static void
928 setrollover(int argc, char *argv[])
929 {
930 
931 	if (argc == 2) {
932 		if (strcasecmp(argv[1], "never") == 0 ||
933 		    strcasecmp(argv[1], "none") == 0) {
934 			options_set_request(OPT_ROLLOVER, NULL);
935 		}
936 		if (strcasecmp(argv[1], "1") == 0) {
937 			options_set_request(OPT_ROLLOVER, "1");
938 		}
939 		if (strcasecmp(argv[1], "0") == 0) {
940 			options_set_request(OPT_ROLLOVER, "0");
941 		}
942 	}
943 	printf("Support for the rollover options is %s.\n",
944 	    options[OPT_ROLLOVER].o_request != NULL ? "enabled" : "disabled");
945 	if (options[OPT_ROLLOVER].o_request != NULL)
946 		printf("Block rollover will be to block %s.\n",
947 		    options[OPT_ROLLOVER].o_request);
948 
949 
950 	printf("\nThe following rollover options are available:\n"
951 	    "\trollover 0	: rollover to block zero (default)\n"
952 	    "\trollover 1	: rollover to block one\n"
953 	    "\trollover never	: do not support the rollover option\n"
954 	    "\trollover none	: do not support the rollover option\n"
955 	);
956 }
957 
958 static void
959 setdebug(int argc, char *argv[])
960 {
961 	int i;
962 
963 	if (argc != 1) {
964 		i = 1;
965 		while (i < argc)
966 			debug ^= debug_find(argv[i++]);
967 	}
968 	printf("The following debugging is enabled: %s\n", debug_show(debug));
969 
970 	printf("\nThe following debugs are available:\n");
971 	i = 0;
972 	while (debugs[i].name != NULL) {
973 		printf("\t%s\t%s\n", debugs[i].name, debugs[i].desc);
974 		i++;
975 	}
976 }
977 
978 static void
979 setblocksize(int argc, char *argv[])
980 {
981 
982 	if (!options_rfc_enabled)
983 		printf("RFC2347 style options are not enabled "
984 		    "(but proceeding anyway)\n");
985 
986 	if (argc != 1) {
987 		int size = atoi(argv[1]);
988 		size_t max;
989 		u_long maxdgram;
990 
991 		max = sizeof(maxdgram);
992 		if (sysctlbyname("net.inet.udp.maxdgram",
993 			&maxdgram, &max, NULL, 0) < 0) {
994 			perror("sysctl: net.inet.udp.maxdgram");
995 			return;
996 		}
997 
998 		if (size < BLKSIZE_MIN || size > BLKSIZE_MAX) {
999 			printf("Blocksize should be between %d and %d bytes.\n",
1000 				BLKSIZE_MIN, BLKSIZE_MAX);
1001 			return;
1002 		} else if (size > (int)maxdgram - 4) {
1003 			printf("Blocksize can't be bigger than %ld bytes due "
1004 			    "to the net.inet.udp.maxdgram sysctl limitation.\n",
1005 			    maxdgram - 4);
1006 			options_set_request(OPT_BLKSIZE, "%ld", maxdgram - 4);
1007 		} else {
1008 			options_set_request(OPT_BLKSIZE, "%d", size);
1009 		}
1010 	}
1011 	printf("Blocksize is now %s bytes.\n", options[OPT_BLKSIZE].o_request);
1012 }
1013 
1014 static void
1015 setblocksize2(int argc, char *argv[])
1016 {
1017 
1018 	if (!options_rfc_enabled || !options_extra_enabled)
1019 		printf(
1020 		    "RFC2347 style or non-RFC defined options are not enabled "
1021 		    "(but proceeding anyway)\n");
1022 
1023 	if (argc != 1) {
1024 		int size = atoi(argv[1]);
1025 		int i;
1026 		size_t max;
1027 		u_long maxdgram;
1028 
1029 		int sizes[] = {
1030 			8, 16, 32, 64, 128, 256, 512, 1024,
1031 			2048, 4096, 8192, 16384, 32768, 0
1032 		};
1033 
1034 		max = sizeof(maxdgram);
1035 		if (sysctlbyname("net.inet.udp.maxdgram",
1036 			&maxdgram, &max, NULL, 0) < 0) {
1037 			perror("sysctl: net.inet.udp.maxdgram");
1038 			return;
1039 		}
1040 
1041 		for (i = 0; sizes[i] != 0; i++) {
1042 			if (sizes[i] == size) break;
1043 		}
1044 		if (sizes[i] == 0) {
1045 			printf("Blocksize2 should be a power of two between "
1046 			    "8 and 32768.\n");
1047 			return;
1048 		}
1049 
1050 		if (size < BLKSIZE_MIN || size > BLKSIZE_MAX) {
1051 			printf("Blocksize2 should be between "
1052 			    "%d and %d bytes.\n", BLKSIZE_MIN, BLKSIZE_MAX);
1053 			return;
1054 		} else if (size > (int)maxdgram - 4) {
1055 			printf("Blocksize2 can't be bigger than %ld bytes due "
1056 			    "to the net.inet.udp.maxdgram sysctl limitation.\n",
1057 			    maxdgram - 4);
1058 			for (i = 0; sizes[i+1] != 0; i++) {
1059 				if ((int)maxdgram < sizes[i+1]) break;
1060 			}
1061 			options_set_request(OPT_BLKSIZE2, "%d", sizes[i]);
1062 		} else {
1063 			options_set_request(OPT_BLKSIZE2, "%d", size);
1064 		}
1065 	}
1066 	printf("Blocksize2 is now %s bytes.\n",
1067 	    options[OPT_BLKSIZE2].o_request);
1068 }
1069 
1070 static void
1071 setpacketdrop(int argc, char *argv[])
1072 {
1073 
1074 	if (argc != 1)
1075 		packetdroppercentage = atoi(argv[1]);
1076 
1077 	printf("Randomly %d in 100 packets will be dropped\n",
1078 	    packetdroppercentage);
1079 }
1080 
1081 static void
1082 setwindowsize(int argc, char *argv[])
1083 {
1084 
1085 	if (!options_rfc_enabled)
1086 		printf("RFC2347 style options are not enabled "
1087 		    "(but proceeding anyway)\n");
1088 
1089 	if (argc != 1) {
1090 		int size = atoi(argv[1]);
1091 
1092 		if (size < WINDOWSIZE_MIN || size > WINDOWSIZE_MAX) {
1093 			printf("Windowsize should be between %d and %d "
1094 			    "blocks.\n", WINDOWSIZE_MIN, WINDOWSIZE_MAX);
1095 			return;
1096 		} else {
1097 			options_set_request(OPT_WINDOWSIZE, "%d", size);
1098 		}
1099 	}
1100 	printf("Windowsize is now %s blocks.\n",
1101 	    options[OPT_WINDOWSIZE].o_request);
1102 }
1103