xref: /freebsd/usr.bin/tftp/main.c (revision 61e21613) 
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 /* Many bug fixes are from Jim Guyton <guyton@rand-unix> */
33 
34 /*
35  * TFTP User Program -- Command Interface.
36  */
37 #include <sys/param.h>
38 #include <sys/file.h>
39 #include <sys/socket.h>
40 #include <sys/stat.h>
41 #include <sys/sysctl.h>
42 
43 #include <netinet/in.h>
44 #include <arpa/inet.h>
45 #include <arpa/tftp.h>
46 
47 #include <ctype.h>
48 #include <err.h>
49 #include <histedit.h>
50 #include <netdb.h>
51 #include <setjmp.h>
52 #include <signal.h>
53 #include <stdbool.h>
54 #include <stddef.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 #include "tftp-utils.h"
61 #include "tftp-io.h"
62 #include "tftp-options.h"
63 #include "tftp.h"
64 
65 #define	MAXLINE		(2 * MAXPATHLEN)
66 #define	TIMEOUT		5		/* secs between rexmt's */
67 
68 typedef struct	sockaddr_storage peeraddr;
69 static int	connected;
70 static char	mode[32];
71 static jmp_buf	toplevel;
72 static int	txrx_error;
73 static int	peer;
74 
75 #define	MAX_MARGV	20
76 static int	margc;
77 static char	*margv[MAX_MARGV];
78 
79 int		verbose;
80 static char	*port = NULL;
81 
82 static void	get(int, char **);
83 static void	help(int, char **);
84 static void	intr(int);
85 static void	modecmd(int, char **);
86 static void	put(int, char **);
87 static void	quit(int, char **);
88 static void	setascii(int, char **);
89 static void	setbinary(int, char **);
90 static void	setpeer0(char *, const char *);
91 static void	setpeer(int, char **);
92 static void	settimeoutpacket(int, char **);
93 static void	settimeoutnetwork(int, char **);
94 static void	setdebug(int, char **);
95 static void	setverbose(int, char **);
96 static void	showstatus(int, char **);
97 static void	setblocksize(int, char **);
98 static void	setblocksize2(int, char **);
99 static void	setoptions(int, char **);
100 static void	setrollover(int, char **);
101 static void	setpacketdrop(int, char **);
102 static void	setwindowsize(int, char **);
103 
104 static void command(bool, EditLine *, History *, HistEvent *) __dead2;
105 static const char *command_prompt(void);
106 
107 static void urihandling(char *URI);
108 static void getusage(char *);
109 static void makeargv(char *line);
110 static void putusage(char *);
111 static void settftpmode(const char *);
112 
113 static char	*tail(char *);
114 static const struct cmd *getcmd(const char *);
115 
116 #define HELPINDENT (sizeof("connect"))
117 
118 struct cmd {
119 	const char	*name;
120 	void	(*handler)(int, char **);
121 	const char	*help;
122 };
123 
124 static struct cmd cmdtab[] = {
125 	{ "connect",	setpeer,	"connect to remote tftp"	},
126 	{ "mode",	modecmd,	"set file transfer mode"	},
127 	{ "put",	put,		"send file"			},
128 	{ "get",	get,		"receive file"			},
129 	{ "quit",	quit,		"exit tftp"			},
130 	{ "verbose",	setverbose,	"toggle verbose mode"		},
131 	{ "status",	showstatus,	"show current status"		},
132 	{ "binary",     setbinary,	"set mode to octet"		},
133 	{ "ascii",      setascii,	"set mode to netascii"		},
134 	{ "rexmt",	settimeoutpacket,
135 	  "set per-packet retransmission timeout[-]" },
136 	{ "timeout",	settimeoutnetwork,
137 	  "set total retransmission timeout" },
138 	{ "trace",	setdebug,	"enable 'debug packet'[-]"	},
139 	{ "debug",	setdebug,	"enable verbose output"		},
140 	{ "blocksize",	setblocksize,	"set blocksize[*]"		},
141 	{ "blocksize2",	setblocksize2,	"set blocksize as a power of 2[**]" },
142 	{ "rollover",	setrollover,	"rollover after 64K packets[**]" },
143 	{ "options",	setoptions,
144 	  "enable or disable RFC2347 style options" },
145 	{ "help",	help,		"print help information"	},
146 	{ "packetdrop",	setpacketdrop,	"artificial packetloss feature"	},
147 	{ "windowsize",	setwindowsize,	"set windowsize[*]"		},
148 	{ "?",		help,		"print help information"	},
149 	{ NULL,		NULL,		NULL				}
150 };
151 
152 static struct	modes {
153 	const char *m_name;
154 	const char *m_mode;
155 } modes[] = {
156 	{ "ascii",	"netascii" },
157 	{ "netascii",	"netascii" },
158 	{ "binary",	"octet" },
159 	{ "image",	"octet" },
160 	{ "octet",	"octet" },
161 	{ NULL,		NULL }
162 };
163 
164 int
165 main(int argc, char *argv[])
166 {
167 	HistEvent he;
168 	static EditLine *el;
169 	static History *hist;
170 	bool interactive;
171 
172 	acting_as_client = 1;
173 	peer = -1;
174 	strcpy(mode, "octet");
175 	signal(SIGINT, intr);
176 
177 	interactive = isatty(STDIN_FILENO);
178 	if (interactive) {
179 		el = el_init("tftp", stdin, stdout, stderr);
180 		hist = history_init();
181 		history(hist, &he, H_SETSIZE, 100);
182 		el_set(el, EL_HIST, history, hist);
183 		el_set(el, EL_EDITOR, "emacs");
184 		el_set(el, EL_PROMPT, command_prompt);
185 		el_set(el, EL_SIGNAL, 1);
186 		el_source(el, NULL);
187 	}
188 
189 	if (argc > 1) {
190 		if (setjmp(toplevel) != 0)
191 			exit(txrx_error);
192 
193 		if (strncmp(argv[1], "tftp://", 7) == 0) {
194 			urihandling(argv[1]);
195 			exit(txrx_error);
196 		}
197 
198 		setpeer(argc, argv);
199 	}
200 
201 	if (setjmp(toplevel) != 0) {
202 		if (interactive)
203 			el_reset(el);
204 		(void)putchar('\n');
205 	}
206 
207 	init_options();
208 	command(interactive, el, hist, &he);
209 }
210 
211 /*
212  * RFC3617 handling of TFTP URIs:
213  *
214  *    tftpURI         = "tftp://" host "/" file [ mode ]
215  *    mode            = ";"  "mode=" ( "netascii" / "octet" )
216  *    file            = *( unreserved / escaped )
217  *    host            = <as specified by RFC 2732>
218  *    unreserved      = <as specified in RFC 2396>
219  *    escaped         = <as specified in RFC 2396>
220  *
221  * We are cheating a little bit by allowing any mode as specified in the
222  * modes table defined earlier on in this file and mapping it on the real
223  * mode.
224  */
225 static void
226 urihandling(char *URI)
227 {
228 	char	uri[ARG_MAX];
229 	char	*host = NULL;
230 	char	*path = NULL;
231 	char	*opts = NULL;
232 	const char *tmode = "octet";
233 	char	*s;
234 	char	line[MAXLINE];
235 	int	i;
236 
237 	strlcpy(uri, URI, ARG_MAX);
238 	host = uri + 7;
239 
240 	if ((s = strchr(host, '/')) == NULL) {
241 		fprintf(stderr,
242 		    "Invalid URI: Couldn't find / after hostname\n");
243 		exit(1);
244 	}
245 	*s = '\0';
246 	path = s + 1;
247 
248 	if ((s = strchr(path, ';')) != NULL) {
249 		*s = '\0';
250 		opts = s + 1;
251 
252 		if (strncmp(opts, "mode=", 5) == 0) {
253 			tmode = opts;
254 			tmode += 5;
255 
256 			for (i = 0; modes[i].m_name != NULL; i++) {
257 				if (strcmp(modes[i].m_name, tmode) == 0)
258 					break;
259 			}
260 			if (modes[i].m_name == NULL) {
261 				fprintf(stderr, "Invalid mode: '%s'\n", mode);
262 				exit(1);
263 			}
264 			settftpmode(modes[i].m_mode);
265 		}
266 	} else {
267 		settftpmode("octet");
268 	}
269 
270 	setpeer0(host, NULL);
271 
272 	sprintf(line, "get %s", path);
273 	makeargv(line);
274 	get(margc, margv);
275 }
276 
277 static char    hostname[MAXHOSTNAMELEN];
278 
279 static void
280 setpeer0(char *host, const char *lport)
281 {
282 	struct addrinfo hints, *res0, *res;
283 	int error;
284 	const char *cause = "unknown";
285 
286 	if (connected) {
287 		close(peer);
288 		peer = -1;
289 	}
290 	connected = 0;
291 
292 	memset(&hints, 0, sizeof(hints));
293 	hints.ai_family = PF_UNSPEC;
294 	hints.ai_socktype = SOCK_DGRAM;
295 	hints.ai_protocol = IPPROTO_UDP;
296 	hints.ai_flags = AI_CANONNAME;
297 	if (!lport)
298 		lport = "tftp";
299 	error = getaddrinfo(host, lport, &hints, &res0);
300 	if (error) {
301 		warnx("%s", gai_strerror(error));
302 		return;
303 	}
304 
305 	for (res = res0; res; res = res->ai_next) {
306 		if (res->ai_addrlen > sizeof(peeraddr))
307 			continue;
308 		peer = socket(res->ai_family, res->ai_socktype,
309 			res->ai_protocol);
310 		if (peer < 0) {
311 			cause = "socket";
312 			continue;
313 		}
314 
315 		memset(&peer_sock, 0, sizeof(peer_sock));
316 		peer_sock.ss_family = res->ai_family;
317 		peer_sock.ss_len = res->ai_addrlen;
318 		if (bind(peer, (struct sockaddr *)&peer_sock, peer_sock.ss_len) < 0) {
319 			cause = "bind";
320 			close(peer);
321 			peer = -1;
322 			continue;
323 		}
324 
325 		break;
326 	}
327 
328 	if (peer < 0)
329 		warn("%s", cause);
330 	else {
331 		/* res->ai_addr <= sizeof(peeraddr) is guaranteed */
332 		memcpy(&peer_sock, res->ai_addr, res->ai_addrlen);
333 		if (res->ai_canonname) {
334 			(void) strlcpy(hostname, res->ai_canonname,
335 				sizeof(hostname));
336 		} else
337 			(void) strlcpy(hostname, host, sizeof(hostname));
338 		connected = 1;
339 	}
340 
341 	freeaddrinfo(res0);
342 }
343 
344 static void
345 setpeer(int argc, char *argv[])
346 {
347 	char	line[MAXLINE];
348 
349 	if (argc < 2) {
350 		strcpy(line, "Connect ");
351 		printf("(to) ");
352 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
353 		makeargv(line);
354 		argc = margc;
355 		argv = margv;
356 	}
357 	if ((argc < 2) || (argc > 3)) {
358 		printf("usage: %s [host [port]]\n", argv[0]);
359 		return;
360 	}
361 	if (argc == 3) {
362 		port = argv[2];
363 		setpeer0(argv[1], argv[2]);
364 	} else
365 		setpeer0(argv[1], NULL);
366 }
367 
368 static void
369 modecmd(int argc, char *argv[])
370 {
371 	struct modes *p;
372 	const char *sep;
373 
374 	if (argc < 2) {
375 		printf("Using %s mode to transfer files.\n", mode);
376 		return;
377 	}
378 	if (argc == 2) {
379 		for (p = modes; p->m_name; p++)
380 			if (strcmp(argv[1], p->m_name) == 0)
381 				break;
382 		if (p->m_name) {
383 			settftpmode(p->m_mode);
384 			return;
385 		}
386 		printf("%s: unknown mode\n", argv[1]);
387 		/* drop through and print usage message */
388 	}
389 
390 	printf("usage: %s [", argv[0]);
391 	sep = " ";
392 	for (p = modes; p->m_name != NULL; p++) {
393 		printf("%s%s", sep, p->m_name);
394 		if (*sep == ' ')
395 			sep = " | ";
396 	}
397 	printf(" ]\n");
398 	return;
399 }
400 
401 static void
402 setbinary(int argc __unused, char *argv[] __unused)
403 {
404 
405 	settftpmode("octet");
406 }
407 
408 static void
409 setascii(int argc __unused, char *argv[] __unused)
410 {
411 
412 	settftpmode("netascii");
413 }
414 
415 static void
416 settftpmode(const char *newmode)
417 {
418 
419 	strlcpy(mode, newmode, sizeof(mode));
420 	if (verbose)
421 		printf("mode set to %s\n", mode);
422 }
423 
424 
425 /*
426  * Send file(s).
427  */
428 static void
429 put(int argc, char *argv[])
430 {
431 	int	fd;
432 	int	n;
433 	char	*cp, *targ, *path;
434 	char	line[MAXLINE];
435 	struct stat sb;
436 
437 	if (argc < 2) {
438 		strcpy(line, "send ");
439 		printf("(file) ");
440 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
441 		makeargv(line);
442 		argc = margc;
443 		argv = margv;
444 	}
445 	if (argc < 2) {
446 		putusage(argv[0]);
447 		return;
448 	}
449 	targ = argv[argc - 1];
450 	if (strrchr(argv[argc - 1], ':')) {
451 		char *lcp;
452 
453 		for (n = 1; n < argc - 1; n++)
454 			if (strchr(argv[n], ':')) {
455 				putusage(argv[0]);
456 				return;
457 			}
458 		lcp = argv[argc - 1];
459 		targ = strrchr(lcp, ':');
460 		*targ++ = 0;
461 		if (lcp[0] == '[' && lcp[strlen(lcp) - 1] == ']') {
462 			lcp[strlen(lcp) - 1] = '\0';
463 			lcp++;
464 		}
465 		setpeer0(lcp, NULL);
466 	}
467 	if (!connected) {
468 		printf("No target machine specified.\n");
469 		return;
470 	}
471 	if (argc < 4) {
472 		cp = argc == 2 ? tail(targ) : argv[1];
473 		fd = open(cp, O_RDONLY);
474 		if (fd < 0) {
475 			warn("%s", cp);
476 			return;
477 		}
478 
479 		if (fstat(fd, &sb) < 0) {
480 			warn("%s", cp);
481 			close(fd);
482 			return;
483 		}
484 		options_set_request(OPT_TSIZE, "%ju", (uintmax_t)sb.st_size);
485 
486 		if (verbose)
487 			printf("putting %s to %s:%s [%s]\n",
488 			    cp, hostname, targ, mode);
489 		if (xmitfile(peer, port, fd, targ, mode))
490 			txrx_error = 1;
491 		close(fd);
492 		return;
493 	}
494 				/* this assumes the target is a directory */
495 				/* on a remote unix system.  hmmmm.  */
496 	for (n = 1; n < argc - 1; n++) {
497 		if (asprintf(&path, "%s/%s", targ, tail(argv[n])) < 0)
498 			err(1, "malloc");
499 
500 		fd = open(argv[n], O_RDONLY);
501 		if (fd < 0) {
502 			warn("%s", argv[n]);
503 			free(path);
504 			continue;
505 		}
506 
507 		if (fstat(fd, &sb) < 0) {
508 			warn("%s", argv[n]);
509 			close(fd);
510 			free(path);
511 			continue;
512 		}
513 		options_set_request(OPT_TSIZE, "%ju", (uintmax_t)sb.st_size);
514 
515 		if (verbose)
516 			printf("putting %s to %s:%s [%s]\n",
517 			    argv[n], hostname, path, mode);
518 		if (xmitfile(peer, port, fd, path, mode) != 0)
519 			txrx_error = 1;
520 		close(fd);
521 
522 		free(path);
523 	}
524 }
525 
526 static void
527 putusage(char *s)
528 {
529 
530 	printf("usage: %s file [remotename]\n", s);
531 	printf("       %s file host:remotename\n", s);
532 	printf("       %s file1 file2 ... fileN [[host:]remote-directory]\n", s);
533 }
534 
535 /*
536  * Receive file(s).
537  */
538 static void
539 get(int argc, char *argv[])
540 {
541 	int fd;
542 	int n;
543 	char *cp;
544 	char *src;
545 	char	line[MAXLINE];
546 
547 	if (argc < 2) {
548 		strcpy(line, "get ");
549 		printf("(files) ");
550 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
551 		makeargv(line);
552 		argc = margc;
553 		argv = margv;
554 	}
555 	if (argc < 2) {
556 		getusage(argv[0]);
557 		return;
558 	}
559 	if (!connected) {
560 		for (n = 1; n < argc ; n++)
561 			if (strrchr(argv[n], ':') == 0) {
562 				printf("No remote host specified and "
563 				    "no host given for file '%s'\n", argv[n]);
564 				getusage(argv[0]);
565 				return;
566 			}
567 	}
568 	for (n = 1; n < argc ; n++) {
569 		src = strrchr(argv[n], ':');
570 		if (src == NULL)
571 			src = argv[n];
572 		else {
573 			char *lcp;
574 
575 			*src++ = 0;
576 			lcp = argv[n];
577 			if (lcp[0] == '[' && lcp[strlen(lcp) - 1] == ']') {
578 				lcp[strlen(lcp) - 1] = '\0';
579 				lcp++;
580 			}
581 			setpeer0(lcp, NULL);
582 			if (!connected)
583 				continue;
584 		}
585 		if (argc < 4) {
586 			cp = argc == 3 ? argv[2] : tail(src);
587 			fd = creat(cp, 0644);
588 			if (fd < 0) {
589 				warn("%s", cp);
590 				return;
591 			}
592 			if (verbose)
593 				printf("getting from %s:%s to %s [%s]\n",
594 				    hostname, src, cp, mode);
595 			if (recvfile(peer, port, fd, src, mode) != 0)
596 				txrx_error = 1;
597 			break;
598 		}
599 		cp = tail(src);         /* new .. jdg */
600 		fd = creat(cp, 0644);
601 		if (fd < 0) {
602 			warn("%s", cp);
603 			continue;
604 		}
605 		if (verbose)
606 			printf("getting from %s:%s to %s [%s]\n",
607 			    hostname, src, cp, mode);
608 		if (recvfile(peer, port, fd, src, mode) != 0)
609 			txrx_error = 1;
610 	}
611 }
612 
613 static void
614 getusage(char *s)
615 {
616 
617 	printf("usage: %s file [localname]\n", s);
618 	printf("       %s [host:]file [localname]\n", s);
619 	printf("       %s [host1:]file1 [host2:]file2 ... [hostN:]fileN\n", s);
620 }
621 
622 static void
623 settimeoutpacket(int argc, char *argv[])
624 {
625 	int t;
626 	char	line[MAXLINE];
627 
628 	if (argc < 2) {
629 		strcpy(line, "Packet timeout ");
630 		printf("(value) ");
631 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
632 		makeargv(line);
633 		argc = margc;
634 		argv = margv;
635 	}
636 	if (argc != 2) {
637 		printf("usage: %s value\n", argv[0]);
638 		return;
639 	}
640 	t = atoi(argv[1]);
641 	if (t < 0) {
642 		printf("%s: bad value\n", argv[1]);
643 		return;
644 	}
645 
646 	settimeouts(t, timeoutnetwork, maxtimeouts);
647 }
648 
649 static void
650 settimeoutnetwork(int argc, char *argv[])
651 {
652 	int t;
653 	char	line[MAXLINE];
654 
655 	if (argc < 2) {
656 		strcpy(line, "Network timeout ");
657 		printf("(value) ");
658 		fgets(&line[strlen(line)], sizeof line - strlen(line), stdin);
659 		makeargv(line);
660 		argc = margc;
661 		argv = margv;
662 	}
663 	if (argc != 2) {
664 		printf("usage: %s value\n", argv[0]);
665 		return;
666 	}
667 	t = atoi(argv[1]);
668 	if (t < 0) {
669 		printf("%s: bad value\n", argv[1]);
670 		return;
671 	}
672 
673 	settimeouts(timeoutpacket, t, maxtimeouts);
674 }
675 
676 static void
677 showstatus(int argc __unused, char *argv[] __unused)
678 {
679 
680 	printf("Remote host: %s\n",
681 	    connected ? hostname : "none specified yet");
682 	printf("RFC2347 Options support: %s\n",
683 	    options_rfc_enabled ? "enabled" : "disabled");
684 	printf("Non-RFC defined options support: %s\n",
685 	    options_extra_enabled ? "enabled" : "disabled");
686 	printf("Mode: %s\n", mode);
687 	printf("Verbose: %s\n", verbose ? "on" : "off");
688 	printf("Debug: %s\n", debug_show(debug));
689 	printf("Artificial packetloss: %d in 100 packets\n",
690 	    packetdroppercentage);
691 	printf("Segment size: %d bytes\n", segsize);
692 	printf("Network timeout: %d seconds\n", timeoutpacket);
693 	printf("Maximum network timeout: %d seconds\n", timeoutnetwork);
694 	printf("Maximum timeouts: %d \n", maxtimeouts);
695 }
696 
697 static void
698 intr(int dummy __unused)
699 {
700 
701 	signal(SIGALRM, SIG_IGN);
702 	alarm(0);
703 	longjmp(toplevel, -1);
704 }
705 
706 static char *
707 tail(char *filename)
708 {
709 	char *s;
710 
711 	while (*filename) {
712 		s = strrchr(filename, '/');
713 		if (s == NULL)
714 			break;
715 		if (s[1])
716 			return (s + 1);
717 		*s = '\0';
718 	}
719 	return (filename);
720 }
721 
722 static const char *
723 command_prompt(void)
724 {
725 
726 	return ("tftp> ");
727 }
728 
729 /*
730  * Command parser.
731  */
732 static void
733 command(bool interactive, EditLine *el, History *hist, HistEvent *hep)
734 {
735 	const struct cmd *c;
736 	const char *bp;
737 	char *cp;
738 	int len, num;
739 	char	line[MAXLINE];
740 
741 	for (;;) {
742 		if (interactive) {
743 			if ((bp = el_gets(el, &num)) == NULL || num == 0)
744 				exit(0);
745 			len = MIN(MAXLINE, num);
746 			memcpy(line, bp, len);
747 			line[len - 1] = '\0';
748 			history(hist, hep, H_ENTER, bp);
749 		} else {
750 			line[0] = 0;
751 			if (fgets(line, sizeof line , stdin) == NULL) {
752 				if (feof(stdin)) {
753 					exit(txrx_error);
754 				} else {
755 					continue;
756 				}
757 			}
758 		}
759 		if ((cp = strchr(line, '\n')))
760 			*cp = '\0';
761 		if (line[0] == 0)
762 			continue;
763 		makeargv(line);
764 		if (margc == 0)
765 			continue;
766 		c = getcmd(margv[0]);
767 		if (c == (struct cmd *)-1) {
768 			printf("?Ambiguous command\n");
769 			continue;
770 		}
771 		if (c == NULL) {
772 			printf("?Invalid command\n");
773 			continue;
774 		}
775 		(*c->handler)(margc, margv);
776 	}
777 }
778 
779 static const struct cmd *
780 getcmd(const char *name)
781 {
782 	const char *p, *q;
783 	const struct cmd *c, *found;
784 	ptrdiff_t longest;
785 	int nmatches;
786 
787 	longest = 0;
788 	nmatches = 0;
789 	found = 0;
790 	for (c = cmdtab; (p = c->name) != NULL; c++) {
791 		for (q = name; *q == *p++; q++)
792 			if (*q == '\0')		/* exact match? */
793 				return (c);
794 		if (*q == '\0') {		/* the name was a prefix */
795 			if (q - name > longest) {
796 				longest = q - name;
797 				nmatches = 1;
798 				found = c;
799 			} else if (q - name == longest)
800 				nmatches++;
801 		}
802 	}
803 	if (nmatches > 1)
804 		return ((struct cmd *)-1);
805 	return (found);
806 }
807 
808 /*
809  * Slice a string up into argc/argv.
810  */
811 static void
812 makeargv(char *line)
813 {
814 	char *cp;
815 	char **argp = margv;
816 
817 	margc = 0;
818 	if ((cp = strchr(line, '\n')) != NULL)
819 		*cp = '\0';
820 	for (cp = line; margc < MAX_MARGV - 1 && *cp != '\0';) {
821 		while (isspace(*cp))
822 			cp++;
823 		if (*cp == '\0')
824 			break;
825 		*argp++ = cp;
826 		margc += 1;
827 		while (*cp != '\0' && !isspace(*cp))
828 			cp++;
829 		if (*cp == '\0')
830 			break;
831 		*cp++ = '\0';
832 	}
833 	*argp++ = 0;
834 }
835 
836 static void
837 quit(int argc __unused, char *argv[] __unused)
838 {
839 
840 	exit(txrx_error);
841 }
842 
843 /*
844  * Help command.
845  */
846 static void
847 help(int argc, char *argv[])
848 {
849 	const struct cmd *c;
850 
851 	if (argc == 1) {
852 		printf("Commands may be abbreviated.  Commands are:\n\n");
853 		for (c = cmdtab; c->name; c++)
854 			printf("%-*s\t%s\n", (int)HELPINDENT, c->name, c->help);
855 
856 		printf("\n[-] : You shouldn't use these ones anymore.\n");
857 		printf("[*] : RFC2347 options support required.\n");
858 		printf("[**] : Non-standard RFC2347 option.\n");
859 		return;
860 	}
861 	while (--argc > 0) {
862 		char *arg;
863 		arg = *++argv;
864 		c = getcmd(arg);
865 		if (c == (struct cmd *)-1)
866 			printf("?Ambiguous help command: %s\n", arg);
867 		else if (c == (struct cmd *)0)
868 			printf("?Invalid help command: %s\n", arg);
869 		else
870 			printf("%s\n", c->help);
871 	}
872 }
873 
874 static void
875 setverbose(int argc __unused, char *argv[] __unused)
876 {
877 
878 	verbose = !verbose;
879 	printf("Verbose mode %s.\n", verbose ? "on" : "off");
880 }
881 
882 static void
883 setoptions(int argc, char *argv[])
884 {
885 
886 	if (argc == 2) {
887 		if (strcasecmp(argv[1], "enable") == 0 ||
888 		    strcasecmp(argv[1], "on") == 0) {
889 			options_extra_enabled = 1;
890 			options_rfc_enabled = 1;
891 		}
892 		if (strcasecmp(argv[1], "disable") == 0 ||
893 		    strcasecmp(argv[1], "off") == 0) {
894 			options_extra_enabled = 0;
895 			options_rfc_enabled = 0;
896 		}
897 		if (strcasecmp(argv[1], "extra") == 0)
898 			options_extra_enabled = !options_extra_enabled;
899 	}
900 	printf("Support for RFC2347 style options are now %s.\n",
901 	    options_rfc_enabled ? "enabled" : "disabled");
902 	printf("Support for non-RFC defined options are now %s.\n",
903 	    options_extra_enabled ? "enabled" : "disabled");
904 
905 	printf("\nThe following options are available:\n"
906 	    "\toptions on	: enable support for RFC2347 style options\n"
907 	    "\toptions off	: disable support for RFC2347 style options\n"
908 	    "\toptions extra	: toggle support for non-RFC defined options\n"
909 	);
910 }
911 
912 static void
913 setrollover(int argc, char *argv[])
914 {
915 
916 	if (argc == 2) {
917 		if (strcasecmp(argv[1], "never") == 0 ||
918 		    strcasecmp(argv[1], "none") == 0) {
919 			options_set_request(OPT_ROLLOVER, NULL);
920 		}
921 		if (strcasecmp(argv[1], "1") == 0) {
922 			options_set_request(OPT_ROLLOVER, "1");
923 		}
924 		if (strcasecmp(argv[1], "0") == 0) {
925 			options_set_request(OPT_ROLLOVER, "0");
926 		}
927 	}
928 	printf("Support for the rollover options is %s.\n",
929 	    options[OPT_ROLLOVER].o_request != NULL ? "enabled" : "disabled");
930 	if (options[OPT_ROLLOVER].o_request != NULL)
931 		printf("Block rollover will be to block %s.\n",
932 		    options[OPT_ROLLOVER].o_request);
933 
934 
935 	printf("\nThe following rollover options are available:\n"
936 	    "\trollover 0	: rollover to block zero (default)\n"
937 	    "\trollover 1	: rollover to block one\n"
938 	    "\trollover never	: do not support the rollover option\n"
939 	    "\trollover none	: do not support the rollover option\n"
940 	);
941 }
942 
943 static void
944 setdebug(int argc, char *argv[])
945 {
946 	int i;
947 
948 	if (argc != 1) {
949 		i = 1;
950 		while (i < argc)
951 			debug ^= debug_find(argv[i++]);
952 	}
953 	printf("The following debugging is enabled: %s\n", debug_show(debug));
954 
955 	printf("\nThe following debugs are available:\n");
956 	i = 0;
957 	while (debugs[i].name != NULL) {
958 		printf("\t%s\t%s\n", debugs[i].name, debugs[i].desc);
959 		i++;
960 	}
961 }
962 
963 static void
964 setblocksize(int argc, char *argv[])
965 {
966 
967 	if (!options_rfc_enabled)
968 		printf("RFC2347 style options are not enabled "
969 		    "(but proceeding anyway)\n");
970 
971 	if (argc != 1) {
972 		int size = atoi(argv[1]);
973 		size_t max;
974 		u_long maxdgram;
975 
976 		max = sizeof(maxdgram);
977 		if (sysctlbyname("net.inet.udp.maxdgram",
978 			&maxdgram, &max, NULL, 0) < 0) {
979 			perror("sysctl: net.inet.udp.maxdgram");
980 			return;
981 		}
982 
983 		if (size < BLKSIZE_MIN || size > BLKSIZE_MAX) {
984 			printf("Blocksize should be between %d and %d bytes.\n",
985 				BLKSIZE_MIN, BLKSIZE_MAX);
986 			return;
987 		} else if (size > (int)maxdgram - 4) {
988 			printf("Blocksize can't be bigger than %ld bytes due "
989 			    "to the net.inet.udp.maxdgram sysctl limitation.\n",
990 			    maxdgram - 4);
991 			options_set_request(OPT_BLKSIZE, "%ld", maxdgram - 4);
992 		} else {
993 			options_set_request(OPT_BLKSIZE, "%d", size);
994 		}
995 	}
996 	printf("Blocksize is now %s bytes.\n", options[OPT_BLKSIZE].o_request);
997 }
998 
999 static void
1000 setblocksize2(int argc, char *argv[])
1001 {
1002 
1003 	if (!options_rfc_enabled || !options_extra_enabled)
1004 		printf(
1005 		    "RFC2347 style or non-RFC defined options are not enabled "
1006 		    "(but proceeding anyway)\n");
1007 
1008 	if (argc != 1) {
1009 		int size = atoi(argv[1]);
1010 		int i;
1011 		size_t max;
1012 		u_long maxdgram;
1013 
1014 		int sizes[] = {
1015 			8, 16, 32, 64, 128, 256, 512, 1024,
1016 			2048, 4096, 8192, 16384, 32768, 0
1017 		};
1018 
1019 		max = sizeof(maxdgram);
1020 		if (sysctlbyname("net.inet.udp.maxdgram",
1021 			&maxdgram, &max, NULL, 0) < 0) {
1022 			perror("sysctl: net.inet.udp.maxdgram");
1023 			return;
1024 		}
1025 
1026 		for (i = 0; sizes[i] != 0; i++) {
1027 			if (sizes[i] == size) break;
1028 		}
1029 		if (sizes[i] == 0) {
1030 			printf("Blocksize2 should be a power of two between "
1031 			    "8 and 32768.\n");
1032 			return;
1033 		}
1034 
1035 		if (size < BLKSIZE_MIN || size > BLKSIZE_MAX) {
1036 			printf("Blocksize2 should be between "
1037 			    "%d and %d bytes.\n", BLKSIZE_MIN, BLKSIZE_MAX);
1038 			return;
1039 		} else if (size > (int)maxdgram - 4) {
1040 			printf("Blocksize2 can't be bigger than %ld bytes due "
1041 			    "to the net.inet.udp.maxdgram sysctl limitation.\n",
1042 			    maxdgram - 4);
1043 			for (i = 0; sizes[i+1] != 0; i++) {
1044 				if ((int)maxdgram < sizes[i+1]) break;
1045 			}
1046 			options_set_request(OPT_BLKSIZE2, "%d", sizes[i]);
1047 		} else {
1048 			options_set_request(OPT_BLKSIZE2, "%d", size);
1049 		}
1050 	}
1051 	printf("Blocksize2 is now %s bytes.\n",
1052 	    options[OPT_BLKSIZE2].o_request);
1053 }
1054 
1055 static void
1056 setpacketdrop(int argc, char *argv[])
1057 {
1058 
1059 	if (argc != 1)
1060 		packetdroppercentage = atoi(argv[1]);
1061 
1062 	printf("Randomly %d in 100 packets will be dropped\n",
1063 	    packetdroppercentage);
1064 }
1065 
1066 static void
1067 setwindowsize(int argc, char *argv[])
1068 {
1069 
1070 	if (!options_rfc_enabled)
1071 		printf("RFC2347 style options are not enabled "
1072 		    "(but proceeding anyway)\n");
1073 
1074 	if (argc != 1) {
1075 		int size = atoi(argv[1]);
1076 
1077 		if (size < WINDOWSIZE_MIN || size > WINDOWSIZE_MAX) {
1078 			printf("Windowsize should be between %d and %d "
1079 			    "blocks.\n", WINDOWSIZE_MIN, WINDOWSIZE_MAX);
1080 			return;
1081 		} else {
1082 			options_set_request(OPT_WINDOWSIZE, "%d", size);
1083 		}
1084 	}
1085 	printf("Windowsize is now %s blocks.\n",
1086 	    options[OPT_WINDOWSIZE].o_request);
1087 }
1088