ssh-keyscan.c revision 124211 
1/*
2 * Copyright 1995, 1996 by David Mazieres <dm@lcs.mit.edu>.
3 *
4 * Modification and redistribution in source and binary forms is
5 * permitted provided that due credit is given to the author and the
6 * OpenBSD project by leaving this copyright notice intact.
7 */
8
9#include "includes.h"
10RCSID("$OpenBSD: ssh-keyscan.c,v 1.44 2003/06/28 16:23:06 deraadt Exp $");
11
12#include "openbsd-compat/sys-queue.h"
13
14#include <openssl/bn.h>
15
16#include <setjmp.h>
17#include "xmalloc.h"
18#include "ssh.h"
19#include "ssh1.h"
20#include "key.h"
21#include "kex.h"
22#include "compat.h"
23#include "myproposal.h"
24#include "packet.h"
25#include "dispatch.h"
26#include "buffer.h"
27#include "bufaux.h"
28#include "log.h"
29#include "atomicio.h"
30#include "misc.h"
31
32/* Flag indicating whether IPv4 or IPv6.  This can be set on the command line.
33   Default value is AF_UNSPEC means both IPv4 and IPv6. */
34int IPv4or6 = AF_UNSPEC;
35
36int ssh_port = SSH_DEFAULT_PORT;
37
38#define KT_RSA1	1
39#define KT_DSA	2
40#define KT_RSA	4
41
42int get_keytypes = KT_RSA1;	/* Get only RSA1 keys by default */
43
44#define MAXMAXFD 256
45
46/* The number of seconds after which to give up on a TCP connection */
47int timeout = 5;
48
49int maxfd;
50#define MAXCON (maxfd - 10)
51
52#ifdef HAVE___PROGNAME
53extern char *__progname;
54#else
55char *__progname;
56#endif
57fd_set *read_wait;
58size_t read_wait_size;
59int ncon;
60int nonfatal_fatal = 0;
61jmp_buf kexjmp;
62Key *kexjmp_key;
63
64/*
65 * Keep a connection structure for each file descriptor.  The state
66 * associated with file descriptor n is held in fdcon[n].
67 */
68typedef struct Connection {
69	u_char c_status;	/* State of connection on this file desc. */
70#define CS_UNUSED 0		/* File descriptor unused */
71#define CS_CON 1		/* Waiting to connect/read greeting */
72#define CS_SIZE 2		/* Waiting to read initial packet size */
73#define CS_KEYS 3		/* Waiting to read public key packet */
74	int c_fd;		/* Quick lookup: c->c_fd == c - fdcon */
75	int c_plen;		/* Packet length field for ssh packet */
76	int c_len;		/* Total bytes which must be read. */
77	int c_off;		/* Length of data read so far. */
78	int c_keytype;		/* Only one of KT_RSA1, KT_DSA, or KT_RSA */
79	char *c_namebase;	/* Address to free for c_name and c_namelist */
80	char *c_name;		/* Hostname of connection for errors */
81	char *c_namelist;	/* Pointer to other possible addresses */
82	char *c_output_name;	/* Hostname of connection for output */
83	char *c_data;		/* Data read from this fd */
84	Kex *c_kex;		/* The key-exchange struct for ssh2 */
85	struct timeval c_tv;	/* Time at which connection gets aborted */
86	TAILQ_ENTRY(Connection) c_link;	/* List of connections in timeout order. */
87} con;
88
89TAILQ_HEAD(conlist, Connection) tq;	/* Timeout Queue */
90con *fdcon;
91
92/*
93 *  This is just a wrapper around fgets() to make it usable.
94 */
95
96/* Stress-test.  Increase this later. */
97#define LINEBUF_SIZE 16
98
99typedef struct {
100	char *buf;
101	u_int size;
102	int lineno;
103	const char *filename;
104	FILE *stream;
105	void (*errfun) (const char *,...);
106} Linebuf;
107
108static Linebuf *
109Linebuf_alloc(const char *filename, void (*errfun) (const char *,...))
110{
111	Linebuf *lb;
112
113	if (!(lb = malloc(sizeof(*lb)))) {
114		if (errfun)
115			(*errfun) ("linebuf (%s): malloc failed\n",
116			    filename ? filename : "(stdin)");
117		return (NULL);
118	}
119	if (filename) {
120		lb->filename = filename;
121		if (!(lb->stream = fopen(filename, "r"))) {
122			xfree(lb);
123			if (errfun)
124				(*errfun) ("%s: %s\n", filename, strerror(errno));
125			return (NULL);
126		}
127	} else {
128		lb->filename = "(stdin)";
129		lb->stream = stdin;
130	}
131
132	if (!(lb->buf = malloc(lb->size = LINEBUF_SIZE))) {
133		if (errfun)
134			(*errfun) ("linebuf (%s): malloc failed\n", lb->filename);
135		xfree(lb);
136		return (NULL);
137	}
138	lb->errfun = errfun;
139	lb->lineno = 0;
140	return (lb);
141}
142
143static void
144Linebuf_free(Linebuf * lb)
145{
146	fclose(lb->stream);
147	xfree(lb->buf);
148	xfree(lb);
149}
150
151#if 0
152static void
153Linebuf_restart(Linebuf * lb)
154{
155	clearerr(lb->stream);
156	rewind(lb->stream);
157	lb->lineno = 0;
158}
159
160static int
161Linebuf_lineno(Linebuf * lb)
162{
163	return (lb->lineno);
164}
165#endif
166
167static char *
168Linebuf_getline(Linebuf * lb)
169{
170	int n = 0;
171	void *p;
172
173	lb->lineno++;
174	for (;;) {
175		/* Read a line */
176		if (!fgets(&lb->buf[n], lb->size - n, lb->stream)) {
177			if (ferror(lb->stream) && lb->errfun)
178				(*lb->errfun)("%s: %s\n", lb->filename,
179				    strerror(errno));
180			return (NULL);
181		}
182		n = strlen(lb->buf);
183
184		/* Return it or an error if it fits */
185		if (n > 0 && lb->buf[n - 1] == '\n') {
186			lb->buf[n - 1] = '\0';
187			return (lb->buf);
188		}
189		if (n != lb->size - 1) {
190			if (lb->errfun)
191				(*lb->errfun)("%s: skipping incomplete last line\n",
192				    lb->filename);
193			return (NULL);
194		}
195		/* Double the buffer if we need more space */
196		lb->size *= 2;
197		if ((p = realloc(lb->buf, lb->size)) == NULL) {
198			lb->size /= 2;
199			if (lb->errfun)
200				(*lb->errfun)("linebuf (%s): realloc failed\n",
201				    lb->filename);
202			return (NULL);
203		}
204		lb->buf = p;
205	}
206}
207
208static int
209fdlim_get(int hard)
210{
211#if defined(HAVE_GETRLIMIT) && defined(RLIMIT_NOFILE)
212	struct rlimit rlfd;
213
214	if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
215		return (-1);
216	if ((hard ? rlfd.rlim_max : rlfd.rlim_cur) == RLIM_INFINITY)
217		return 10000;
218	else
219		return hard ? rlfd.rlim_max : rlfd.rlim_cur;
220#elif defined (HAVE_SYSCONF)
221	return sysconf (_SC_OPEN_MAX);
222#else
223	return 10000;
224#endif
225}
226
227static int
228fdlim_set(int lim)
229{
230#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE)
231	struct rlimit rlfd;
232#endif
233
234	if (lim <= 0)
235		return (-1);
236#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_NOFILE)
237	if (getrlimit(RLIMIT_NOFILE, &rlfd) < 0)
238		return (-1);
239	rlfd.rlim_cur = lim;
240	if (setrlimit(RLIMIT_NOFILE, &rlfd) < 0)
241		return (-1);
242#elif defined (HAVE_SETDTABLESIZE)
243	setdtablesize(lim);
244#endif
245	return (0);
246}
247
248/*
249 * This is an strsep function that returns a null field for adjacent
250 * separators.  This is the same as the 4.4BSD strsep, but different from the
251 * one in the GNU libc.
252 */
253static char *
254xstrsep(char **str, const char *delim)
255{
256	char *s, *e;
257
258	if (!**str)
259		return (NULL);
260
261	s = *str;
262	e = s + strcspn(s, delim);
263
264	if (*e != '\0')
265		*e++ = '\0';
266	*str = e;
267
268	return (s);
269}
270
271/*
272 * Get the next non-null token (like GNU strsep).  Strsep() will return a
273 * null token for two adjacent separators, so we may have to loop.
274 */
275static char *
276strnnsep(char **stringp, char *delim)
277{
278	char *tok;
279
280	do {
281		tok = xstrsep(stringp, delim);
282	} while (tok && *tok == '\0');
283	return (tok);
284}
285
286static Key *
287keygrab_ssh1(con *c)
288{
289	static Key *rsa;
290	static Buffer msg;
291
292	if (rsa == NULL) {
293		buffer_init(&msg);
294		rsa = key_new(KEY_RSA1);
295	}
296	buffer_append(&msg, c->c_data, c->c_plen);
297	buffer_consume(&msg, 8 - (c->c_plen & 7));	/* padding */
298	if (buffer_get_char(&msg) != (int) SSH_SMSG_PUBLIC_KEY) {
299		error("%s: invalid packet type", c->c_name);
300		buffer_clear(&msg);
301		return NULL;
302	}
303	buffer_consume(&msg, 8);		/* cookie */
304
305	/* server key */
306	(void) buffer_get_int(&msg);
307	buffer_get_bignum(&msg, rsa->rsa->e);
308	buffer_get_bignum(&msg, rsa->rsa->n);
309
310	/* host key */
311	(void) buffer_get_int(&msg);
312	buffer_get_bignum(&msg, rsa->rsa->e);
313	buffer_get_bignum(&msg, rsa->rsa->n);
314
315	buffer_clear(&msg);
316
317	return (rsa);
318}
319
320static int
321hostjump(Key *hostkey)
322{
323	kexjmp_key = hostkey;
324	longjmp(kexjmp, 1);
325}
326
327static int
328ssh2_capable(int remote_major, int remote_minor)
329{
330	switch (remote_major) {
331	case 1:
332		if (remote_minor == 99)
333			return 1;
334		break;
335	case 2:
336		return 1;
337	default:
338		break;
339	}
340	return 0;
341}
342
343static Key *
344keygrab_ssh2(con *c)
345{
346	int j;
347
348	packet_set_connection(c->c_fd, c->c_fd);
349	enable_compat20();
350	myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = c->c_keytype == KT_DSA?
351	    "ssh-dss": "ssh-rsa";
352	c->c_kex = kex_setup(myproposal);
353	c->c_kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
354	c->c_kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
355	c->c_kex->verify_host_key = hostjump;
356
357	if (!(j = setjmp(kexjmp))) {
358		nonfatal_fatal = 1;
359		dispatch_run(DISPATCH_BLOCK, &c->c_kex->done, c->c_kex);
360		fprintf(stderr, "Impossible! dispatch_run() returned!\n");
361		exit(1);
362	}
363	nonfatal_fatal = 0;
364	xfree(c->c_kex);
365	c->c_kex = NULL;
366	packet_close();
367
368	return j < 0? NULL : kexjmp_key;
369}
370
371static void
372keyprint(con *c, Key *key)
373{
374	if (!key)
375		return;
376
377	fprintf(stdout, "%s ", c->c_output_name ? c->c_output_name : c->c_name);
378	key_write(key, stdout);
379	fputs("\n", stdout);
380}
381
382static int
383tcpconnect(char *host)
384{
385	struct addrinfo hints, *ai, *aitop;
386	char strport[NI_MAXSERV];
387	int gaierr, s = -1;
388
389	snprintf(strport, sizeof strport, "%d", ssh_port);
390	memset(&hints, 0, sizeof(hints));
391	hints.ai_family = IPv4or6;
392	hints.ai_socktype = SOCK_STREAM;
393	if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
394		fatal("getaddrinfo %s: %s", host, gai_strerror(gaierr));
395	for (ai = aitop; ai; ai = ai->ai_next) {
396		s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
397		if (s < 0) {
398			error("socket: %s", strerror(errno));
399			continue;
400		}
401		if (fcntl(s, F_SETFL, O_NONBLOCK) < 0)
402			fatal("F_SETFL: %s", strerror(errno));
403		if (connect(s, ai->ai_addr, ai->ai_addrlen) < 0 &&
404		    errno != EINPROGRESS)
405			error("connect (`%s'): %s", host, strerror(errno));
406		else
407			break;
408		close(s);
409		s = -1;
410	}
411	freeaddrinfo(aitop);
412	return s;
413}
414
415static int
416conalloc(char *iname, char *oname, int keytype)
417{
418	char *namebase, *name, *namelist;
419	int s;
420
421	namebase = namelist = xstrdup(iname);
422
423	do {
424		name = xstrsep(&namelist, ",");
425		if (!name) {
426			xfree(namebase);
427			return (-1);
428		}
429	} while ((s = tcpconnect(name)) < 0);
430
431	if (s >= maxfd)
432		fatal("conalloc: fdno %d too high", s);
433	if (fdcon[s].c_status)
434		fatal("conalloc: attempt to reuse fdno %d", s);
435
436	fdcon[s].c_fd = s;
437	fdcon[s].c_status = CS_CON;
438	fdcon[s].c_namebase = namebase;
439	fdcon[s].c_name = name;
440	fdcon[s].c_namelist = namelist;
441	fdcon[s].c_output_name = xstrdup(oname);
442	fdcon[s].c_data = (char *) &fdcon[s].c_plen;
443	fdcon[s].c_len = 4;
444	fdcon[s].c_off = 0;
445	fdcon[s].c_keytype = keytype;
446	gettimeofday(&fdcon[s].c_tv, NULL);
447	fdcon[s].c_tv.tv_sec += timeout;
448	TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
449	FD_SET(s, read_wait);
450	ncon++;
451	return (s);
452}
453
454static void
455confree(int s)
456{
457	if (s >= maxfd || fdcon[s].c_status == CS_UNUSED)
458		fatal("confree: attempt to free bad fdno %d", s);
459	close(s);
460	xfree(fdcon[s].c_namebase);
461	xfree(fdcon[s].c_output_name);
462	if (fdcon[s].c_status == CS_KEYS)
463		xfree(fdcon[s].c_data);
464	fdcon[s].c_status = CS_UNUSED;
465	fdcon[s].c_keytype = 0;
466	TAILQ_REMOVE(&tq, &fdcon[s], c_link);
467	FD_CLR(s, read_wait);
468	ncon--;
469}
470
471static void
472contouch(int s)
473{
474	TAILQ_REMOVE(&tq, &fdcon[s], c_link);
475	gettimeofday(&fdcon[s].c_tv, NULL);
476	fdcon[s].c_tv.tv_sec += timeout;
477	TAILQ_INSERT_TAIL(&tq, &fdcon[s], c_link);
478}
479
480static int
481conrecycle(int s)
482{
483	con *c = &fdcon[s];
484	int ret;
485
486	ret = conalloc(c->c_namelist, c->c_output_name, c->c_keytype);
487	confree(s);
488	return (ret);
489}
490
491static void
492congreet(int s)
493{
494	int remote_major, remote_minor, n = 0;
495	char buf[256], *cp;
496	char remote_version[sizeof buf];
497	size_t bufsiz;
498	con *c = &fdcon[s];
499
500	bufsiz = sizeof(buf);
501	cp = buf;
502	while (bufsiz-- && (n = read(s, cp, 1)) == 1 && *cp != '\n') {
503		if (*cp == '\r')
504			*cp = '\n';
505		cp++;
506	}
507	if (n < 0) {
508		if (errno != ECONNREFUSED)
509			error("read (%s): %s", c->c_name, strerror(errno));
510		conrecycle(s);
511		return;
512	}
513	if (n == 0) {
514		error("%s: Connection closed by remote host", c->c_name);
515		conrecycle(s);
516		return;
517	}
518	if (*cp != '\n' && *cp != '\r') {
519		error("%s: bad greeting", c->c_name);
520		confree(s);
521		return;
522	}
523	*cp = '\0';
524	if (sscanf(buf, "SSH-%d.%d-%[^\n]\n",
525	    &remote_major, &remote_minor, remote_version) == 3)
526		compat_datafellows(remote_version);
527	else
528		datafellows = 0;
529	if (c->c_keytype != KT_RSA1) {
530		if (!ssh2_capable(remote_major, remote_minor)) {
531			debug("%s doesn't support ssh2", c->c_name);
532			confree(s);
533			return;
534		}
535	} else if (remote_major != 1) {
536		debug("%s doesn't support ssh1", c->c_name);
537		confree(s);
538		return;
539	}
540	fprintf(stderr, "# %s %s\n", c->c_name, chop(buf));
541	n = snprintf(buf, sizeof buf, "SSH-%d.%d-OpenSSH-keyscan\r\n",
542	    c->c_keytype == KT_RSA1? PROTOCOL_MAJOR_1 : PROTOCOL_MAJOR_2,
543	    c->c_keytype == KT_RSA1? PROTOCOL_MINOR_1 : PROTOCOL_MINOR_2);
544	if (atomicio(vwrite, s, buf, n) != n) {
545		error("write (%s): %s", c->c_name, strerror(errno));
546		confree(s);
547		return;
548	}
549	if (c->c_keytype != KT_RSA1) {
550		keyprint(c, keygrab_ssh2(c));
551		confree(s);
552		return;
553	}
554	c->c_status = CS_SIZE;
555	contouch(s);
556}
557
558static void
559conread(int s)
560{
561	con *c = &fdcon[s];
562	int n;
563
564	if (c->c_status == CS_CON) {
565		congreet(s);
566		return;
567	}
568	n = read(s, c->c_data + c->c_off, c->c_len - c->c_off);
569	if (n < 0) {
570		error("read (%s): %s", c->c_name, strerror(errno));
571		confree(s);
572		return;
573	}
574	c->c_off += n;
575
576	if (c->c_off == c->c_len)
577		switch (c->c_status) {
578		case CS_SIZE:
579			c->c_plen = htonl(c->c_plen);
580			c->c_len = c->c_plen + 8 - (c->c_plen & 7);
581			c->c_off = 0;
582			c->c_data = xmalloc(c->c_len);
583			c->c_status = CS_KEYS;
584			break;
585		case CS_KEYS:
586			keyprint(c, keygrab_ssh1(c));
587			confree(s);
588			return;
589			break;
590		default:
591			fatal("conread: invalid status %d", c->c_status);
592			break;
593		}
594
595	contouch(s);
596}
597
598static void
599conloop(void)
600{
601	struct timeval seltime, now;
602	fd_set *r, *e;
603	con *c;
604	int i;
605
606	gettimeofday(&now, NULL);
607	c = TAILQ_FIRST(&tq);
608
609	if (c && (c->c_tv.tv_sec > now.tv_sec ||
610	    (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec > now.tv_usec))) {
611		seltime = c->c_tv;
612		seltime.tv_sec -= now.tv_sec;
613		seltime.tv_usec -= now.tv_usec;
614		if (seltime.tv_usec < 0) {
615			seltime.tv_usec += 1000000;
616			seltime.tv_sec--;
617		}
618	} else
619		seltime.tv_sec = seltime.tv_usec = 0;
620
621	r = xmalloc(read_wait_size);
622	memcpy(r, read_wait, read_wait_size);
623	e = xmalloc(read_wait_size);
624	memcpy(e, read_wait, read_wait_size);
625
626	while (select(maxfd, r, NULL, e, &seltime) == -1 &&
627	    (errno == EAGAIN || errno == EINTR))
628		;
629
630	for (i = 0; i < maxfd; i++) {
631		if (FD_ISSET(i, e)) {
632			error("%s: exception!", fdcon[i].c_name);
633			confree(i);
634		} else if (FD_ISSET(i, r))
635			conread(i);
636	}
637	xfree(r);
638	xfree(e);
639
640	c = TAILQ_FIRST(&tq);
641	while (c && (c->c_tv.tv_sec < now.tv_sec ||
642	    (c->c_tv.tv_sec == now.tv_sec && c->c_tv.tv_usec < now.tv_usec))) {
643		int s = c->c_fd;
644
645		c = TAILQ_NEXT(c, c_link);
646		conrecycle(s);
647	}
648}
649
650static void
651do_host(char *host)
652{
653	char *name = strnnsep(&host, " \t\n");
654	int j;
655
656	if (name == NULL)
657		return;
658	for (j = KT_RSA1; j <= KT_RSA; j *= 2) {
659		if (get_keytypes & j) {
660			while (ncon >= MAXCON)
661				conloop();
662			conalloc(name, *host ? host : name, j);
663		}
664	}
665}
666
667void
668fatal(const char *fmt,...)
669{
670	va_list args;
671
672	va_start(args, fmt);
673	do_log(SYSLOG_LEVEL_FATAL, fmt, args);
674	va_end(args);
675	if (nonfatal_fatal)
676		longjmp(kexjmp, -1);
677	else
678		fatal_cleanup();
679}
680
681static void
682usage(void)
683{
684	fprintf(stderr, "usage: %s [-v46] [-p port] [-T timeout] [-t type] [-f file]\n"
685	    "\t\t   [host | addrlist namelist] [...]\n",
686	    __progname);
687	exit(1);
688}
689
690int
691main(int argc, char **argv)
692{
693	int debug_flag = 0, log_level = SYSLOG_LEVEL_INFO;
694	int opt, fopt_count = 0;
695	char *tname;
696
697	extern int optind;
698	extern char *optarg;
699
700	__progname = ssh_get_progname(argv[0]);
701	init_rng();
702	seed_rng();
703	TAILQ_INIT(&tq);
704
705	if (argc <= 1)
706		usage();
707
708	while ((opt = getopt(argc, argv, "v46p:T:t:f:")) != -1) {
709		switch (opt) {
710		case 'p':
711			ssh_port = a2port(optarg);
712			if (ssh_port == 0) {
713				fprintf(stderr, "Bad port '%s'\n", optarg);
714				exit(1);
715			}
716			break;
717		case 'T':
718			timeout = convtime(optarg);
719			if (timeout == -1 || timeout == 0) {
720				fprintf(stderr, "Bad timeout '%s'\n", optarg);
721				usage();
722			}
723			break;
724		case 'v':
725			if (!debug_flag) {
726				debug_flag = 1;
727				log_level = SYSLOG_LEVEL_DEBUG1;
728			}
729			else if (log_level < SYSLOG_LEVEL_DEBUG3)
730				log_level++;
731			else
732				fatal("Too high debugging level.");
733			break;
734		case 'f':
735			if (strcmp(optarg, "-") == 0)
736				optarg = NULL;
737			argv[fopt_count++] = optarg;
738			break;
739		case 't':
740			get_keytypes = 0;
741			tname = strtok(optarg, ",");
742			while (tname) {
743				int type = key_type_from_name(tname);
744				switch (type) {
745				case KEY_RSA1:
746					get_keytypes |= KT_RSA1;
747					break;
748				case KEY_DSA:
749					get_keytypes |= KT_DSA;
750					break;
751				case KEY_RSA:
752					get_keytypes |= KT_RSA;
753					break;
754				case KEY_UNSPEC:
755					fatal("unknown key type %s", tname);
756				}
757				tname = strtok(NULL, ",");
758			}
759			break;
760		case '4':
761			IPv4or6 = AF_INET;
762			break;
763		case '6':
764			IPv4or6 = AF_INET6;
765			break;
766		case '?':
767		default:
768			usage();
769		}
770	}
771	if (optind == argc && !fopt_count)
772		usage();
773
774	log_init("ssh-keyscan", log_level, SYSLOG_FACILITY_USER, 1);
775
776	maxfd = fdlim_get(1);
777	if (maxfd < 0)
778		fatal("%s: fdlim_get: bad value", __progname);
779	if (maxfd > MAXMAXFD)
780		maxfd = MAXMAXFD;
781	if (MAXCON <= 0)
782		fatal("%s: not enough file descriptors", __progname);
783	if (maxfd > fdlim_get(0))
784		fdlim_set(maxfd);
785	fdcon = xmalloc(maxfd * sizeof(con));
786	memset(fdcon, 0, maxfd * sizeof(con));
787
788	read_wait_size = howmany(maxfd, NFDBITS) * sizeof(fd_mask);
789	read_wait = xmalloc(read_wait_size);
790	memset(read_wait, 0, read_wait_size);
791
792	if (fopt_count) {
793		Linebuf *lb;
794		char *line;
795		int j;
796
797		for (j = 0; j < fopt_count; j++) {
798			lb = Linebuf_alloc(argv[j], error);
799			if (!lb)
800				continue;
801			while ((line = Linebuf_getline(lb)) != NULL)
802				do_host(line);
803			Linebuf_free(lb);
804		}
805	}
806
807	while (optind < argc)
808		do_host(argv[optind++]);
809
810	while (ncon > 0)
811		conloop();
812
813	return (0);
814}
815